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He X, Zhang H, Nose T, Katase T, Tadano T, Ide K, Ueda S, Hiramatsu H, Hosono H, Kamiya T. Degenerated Hole Doping and Ultra-Low Lattice Thermal Conductivity in Polycrystalline SnSe by Nonequilibrium Isovalent Te Substitution. Adv Sci (Weinh) 2022; 9:e2105958. [PMID: 35257520 PMCID: PMC9069380 DOI: 10.1002/advs.202105958] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/22/2021] [Revised: 02/16/2022] [Indexed: 06/14/2023]
Abstract
Tin mono-selenide (SnSe) exhibits the world record of thermoelectric conversion efficiency ZT in the single crystal form, but the performance of polycrystalline SnSe is restricted by low electronic conductivity (σ) and high thermal conductivity (κ), compared to those of the single crystal. Here an effective strategy to achieve high σ and low κ simultaneously is reported on p-type polycrystalline SnSe with isovalent Te ion substitution. The nonequilibrium Sn(Se1- x Tex ) solid solution bulks with x up to 0.4 are synthesized by the two-step process composed of high-temperature solid-state reaction and rapid thermal quenching. The Te ion substitution in SnSe realizes high σ due to the 103 -times increase in hole carrier concentration and effectively reduced lattice κ less than one-third at room temperature. The large-size Te ion in Sn(Se1- x Tex ) forms weak SnTe bonds, leading to the high-density formation of hole-donating Sn vacancies and the reduced phonon frequency and enhanced phonon scattering. This result-doping of large-size ions beyond the equilibrium limit-proposes a new idea for carrier doping and controlling thermal properties to enhance the ZT of polycrystalline SnSe.
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Affiliation(s)
- Xinyi He
- Laboratory for Materials and Structures, Institute of Innovative ResearchTokyo Institute of Technology4259 Nagatsuta, MidoriYokohama226‐8503Japan
| | - Haoyun Zhang
- Laboratory for Materials and Structures, Institute of Innovative ResearchTokyo Institute of Technology4259 Nagatsuta, MidoriYokohama226‐8503Japan
| | - Takumi Nose
- Laboratory for Materials and Structures, Institute of Innovative ResearchTokyo Institute of Technology4259 Nagatsuta, MidoriYokohama226‐8503Japan
| | - Takayoshi Katase
- Laboratory for Materials and Structures, Institute of Innovative ResearchTokyo Institute of Technology4259 Nagatsuta, MidoriYokohama226‐8503Japan
| | - Terumasa Tadano
- Research Center for Magnetic and Spintronic MaterialsNational Institute for Materials Science1‐2‐1 SengenTsukubaIbaraki305‐0047Japan
| | - Keisuke Ide
- Laboratory for Materials and Structures, Institute of Innovative ResearchTokyo Institute of Technology4259 Nagatsuta, MidoriYokohama226‐8503Japan
| | - Shigenori Ueda
- Research Center for Functional MaterialsNational Institute for Materials ScienceNamikiTsukuba305‐0044Japan
- Research Center for Advanced Measurement and CharacterizationNational Institute for Materials ScienceTsukuba305‐0047Japan
- Synchrotron X‐ray Station at SPring‐8National Institute for Materials Science1‐1‐1 SayoHyogo679‐5148Japan
| | - Hidenori Hiramatsu
- Laboratory for Materials and Structures, Institute of Innovative ResearchTokyo Institute of Technology4259 Nagatsuta, MidoriYokohama226‐8503Japan
- Materials Research Center for Element StrategyTokyo Institute of Technology4259 Nagatsuta, MidoriYokohama226‐8503Japan
| | - Hideo Hosono
- Materials Research Center for Element StrategyTokyo Institute of Technology4259 Nagatsuta, MidoriYokohama226‐8503Japan
| | - Toshio Kamiya
- Laboratory for Materials and Structures, Institute of Innovative ResearchTokyo Institute of Technology4259 Nagatsuta, MidoriYokohama226‐8503Japan
- Materials Research Center for Element StrategyTokyo Institute of Technology4259 Nagatsuta, MidoriYokohama226‐8503Japan
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He X, Chen J, Katase T, Minohara M, Ide K, Hiramatsu H, Kumigashira H, Hosono H, Kamiya T. High-Mobility Metastable Rock-Salt Type (Sn,Ca)Se Thin Film Stabilized by Direct Epitaxial Growth on a YSZ (111) Single-Crystal Substrate. ACS Appl Mater Interfaces 2022; 14:18682-18689. [PMID: 35420024 DOI: 10.1021/acsami.2c01464] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Metastable cubic (Sn1-xPbx)Se with x ≥ 0.5 is expected to be a high mobility semiconductor due to its Dirac-like electronic state, but it has an excessively high carrier concentration of ∼1019 cm-3 and is not suitable for semiconductor device applications such as thin film transistors and solar cells. Further, thin films of (Sn1-xPbx)Se require a complicated synthesis process because of the high vapor pressure of Pb. We herein report the direct growth of metastable cubic (Sn1-xCax)Se films alloyed with CaSe, which has a wider bandgap and lower vapor pressure than PbSe. The cubic (Sn1-xCax)Se epitaxial films with x = 0.4-0.8 are stabilized on YSZ (111) single crystalline substrates by pulsed laser deposition. (Sn1-xCax)Se has a direct-transition-type bandgap, and the bandgap energy can be varied from 1.4 eV (x = 0.4) to 2.0 eV (x = 0.8) by changing x. These films with x = 0.4-0.6 show p-type conduction with low hole carrier concentrations of ∼1017 cm-3. Hall mobility analysis suggests that the hole transport would be dominated by 180° rotational domain structures, which is specific to (111) oriented epitaxial films. However, it, in turn, clarifies that the in-grain carrier mobility in the (Sn0.6Ca0.4)Se film is as high as 322 cm2/(Vs), which is much higher than those in thermodynamically stable layered SnSe and other Sn-based layered semiconductor films at room temperature. Therefore, the present results prove the potential of high mobility (Sn1-xCax)Se films for semiconductor device applications via a simple thin-film deposition process.
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Affiliation(s)
- Xinyi He
- Laboratory for Materials and Structures, Institute of Innovative Research, Tokyo Institute of Technology, 4259 Nagatsuta-cho, Midori-ku, Yokohama, 226-8503, Japan
| | - Jinshuai Chen
- Laboratory for Materials and Structures, Institute of Innovative Research, Tokyo Institute of Technology, 4259 Nagatsuta-cho, Midori-ku, Yokohama, 226-8503, Japan
| | - Takayoshi Katase
- Laboratory for Materials and Structures, Institute of Innovative Research, Tokyo Institute of Technology, 4259 Nagatsuta-cho, Midori-ku, Yokohama, 226-8503, Japan
| | - Makoto Minohara
- Research Institute for Advanced Electronics and Photonics, National Institute of Advanced Industrial Science and Technology, Tsukuba, Ibaraki 305-8568, Japan
| | - Keisuke Ide
- Laboratory for Materials and Structures, Institute of Innovative Research, Tokyo Institute of Technology, 4259 Nagatsuta-cho, Midori-ku, Yokohama, 226-8503, Japan
| | - Hidenori Hiramatsu
- Laboratory for Materials and Structures, Institute of Innovative Research, Tokyo Institute of Technology, 4259 Nagatsuta-cho, Midori-ku, Yokohama, 226-8503, Japan
- Materials Research Center for Element Strategy, Tokyo Institute of Technology, 4259 Nagatsuta-cho, Midori-ku, Yokohama, 226-8503, Japan
| | - Hiroshi Kumigashira
- Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, Sendai 980-8577, Japan
| | - Hideo Hosono
- Materials Research Center for Element Strategy, Tokyo Institute of Technology, 4259 Nagatsuta-cho, Midori-ku, Yokohama, 226-8503, Japan
| | - Toshio Kamiya
- Laboratory for Materials and Structures, Institute of Innovative Research, Tokyo Institute of Technology, 4259 Nagatsuta-cho, Midori-ku, Yokohama, 226-8503, Japan
- Materials Research Center for Element Strategy, Tokyo Institute of Technology, 4259 Nagatsuta-cho, Midori-ku, Yokohama, 226-8503, Japan
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53
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Garfinkel DA, Tang N, Pakeltis G, Emery R, Ivanov IN, Gilbert DA, Rack PD. Magnetic and Optical Properties of Au-Co Solid Solution and Phase-Separated Thin Films and Nanoparticles. ACS Appl Mater Interfaces 2022; 14:15047-15058. [PMID: 35333040 DOI: 10.1021/acsami.2c02028] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
The chemical composition and morphology of AuxCo1-x thin films and nanoparticles are controlled via a combination of cosputtering, pulsed laser-induced dewetting (PLiD), and annealing, leading to tunable magnetic and optical properties. Regardless of chemical composition, the as-deposited thin films and as-PLiD nanoparticles are found to possess a face-centered cubic (FCC) AuxCo1-x solid-solution crystal structure. Annealing results in large phase-separated grains of Au and Co in both the thin films and nanostructures for all chemical compositions. The magnetic and optical properties are characterized via vibrating sample magnetometry (VSM), ellipsometry, optical transmission spectroscopy, and electron energy loss spectroscopy (EELS). Despite the exceptionally high magnetic anisotropy inherent to Co, the presence of sufficient Au (72 atom %) in the AuxCo1-x solid solution results in superparamagnetic thin films. Among the as-PLiD nanoparticle samples, an increased Co composition leads to a departure from traditional ferromagnetism in favor of wasp-waisted hysteresis caused by magnetic vortices. Phase separation resulting from annealing leads to ferromagnetism for all compositions in both the thin films and nanoparticles. The optical properties of AuxCo1-x nanostructures are also largely influenced by the chemical morphology, where the AuxCo1-x intermixed solid solution has significantly damped plasmonic performance relative to pure Au and comparable to pure Co. Phase separation greatly enhances the quality factor, optical absorption, and electron energy loss spectroscopy (EELS) signatures. The enhancement of the localized surface plasmon resonances (LSPRs) scales with the reduction in Co composition, despite EELS evidence that excitation of the Co portions of a nanoparticle can provide a similar, and in some instances enhanced, LSPR resonance compared to Au. This behavior, however, is seemingly limited to the LSPR dipole mode, while higher-order modes are greatly damped by a Co aloof position. This observed magneto-plasmonic functionality and tunability could be applicable in biomedicine, namely, cancer therapeutics.
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Affiliation(s)
- David A Garfinkel
- Department of Materials Science and Engineering, University of Tennessee, Knoxville, Tennessee 37996, United States
| | - Nan Tang
- Department of Materials Science and Engineering, University of Tennessee, Knoxville, Tennessee 37996, United States
| | - Grace Pakeltis
- Department of Materials Science and Engineering, University of Tennessee, Knoxville, Tennessee 37996, United States
| | - Reece Emery
- Department of Materials Science and Engineering, University of Tennessee, Knoxville, Tennessee 37996, United States
| | - Ilia N Ivanov
- Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
| | - Dustin A Gilbert
- Department of Materials Science and Engineering, University of Tennessee, Knoxville, Tennessee 37996, United States
| | - Philip D Rack
- Department of Materials Science and Engineering, University of Tennessee, Knoxville, Tennessee 37996, United States
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He Z, Rong T, Li Y, Ma J, Li Q, Wu F, Wang Y, Wang F. Two-Dimensional TiVC Solid-Solution MXene as Surface-Enhanced Raman Scattering Substrate. ACS Nano 2022; 16:4072-4083. [PMID: 35179019 DOI: 10.1021/acsnano.1c09736] [Citation(s) in RCA: 29] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Two-dimensional (2D) MXenes are attractive candidates as surface-enhanced Raman scattering (SERS) substrates because of their metallic conductivity and abundant surface terminations. Herein, we report the facile synthesis of bimetallic solid-solution TiVC (MXene) and its application in SERS. The few-layered MXene nanosheets with high crystallinity were successfully prepared using a one-step chemical etching method without ultrasonic and organic solvent intercalation steps. SERS activity of the as-prepared MXene was investigated by fabricating free-standing TiVC film as the substrate. A SERS enhancement factor of 1012 and femtomolar-level detection limit were confirmed using rhodamine 6G as a model dye with 532 nm excitation. The fluorescent signal of the rhodamine 6G dye was effectively quenched, making the SERS spectrum clearly distinguishable. Furthermore, we demonstrate that the TiVC-analyte system with ultrahigh sensitivity is dominated by the chemical mechanism (CM) based on the experimental and simulation results. The abundant density of states near the Fermi level of the TiVC and the strong interaction between the TiVC and analyte promote the intermolecular charge transfer resonance in the TiVC-analyte complex, resulting in significant Raman enhancement. Additionally, several other probe molecules were used for SERS detection to further verify CM-based selectivity enhancement on the TiVC substrates. This work provides guidance for the facile synthesis of 2D MXene and its application in ultrasensitive SERS detection.
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Affiliation(s)
- Zhiquan He
- Beijing Key Laboratory for Magneto-Photoelectrical Composite and Interface Science, School of Mathematics and Physics, University of Science and Technology Beijing, Beijing 100083, China
| | - Tengda Rong
- Beijing Key Laboratory for Magneto-Photoelectrical Composite and Interface Science, School of Mathematics and Physics, University of Science and Technology Beijing, Beijing 100083, China
| | - Yan Li
- Beijing Key Laboratory for Magneto-Photoelectrical Composite and Interface Science, School of Mathematics and Physics, University of Science and Technology Beijing, Beijing 100083, China
| | - Junjie Ma
- Beijing Key Laboratory for Magneto-Photoelectrical Composite and Interface Science, School of Mathematics and Physics, University of Science and Technology Beijing, Beijing 100083, China
| | - Quanshui Li
- Beijing Key Laboratory for Magneto-Photoelectrical Composite and Interface Science, School of Mathematics and Physics, University of Science and Technology Beijing, Beijing 100083, China
| | - Furong Wu
- Beijing Key Laboratory for Magneto-Photoelectrical Composite and Interface Science, School of Mathematics and Physics, University of Science and Technology Beijing, Beijing 100083, China
| | - Yuhang Wang
- Beijing Key Laboratory for Magneto-Photoelectrical Composite and Interface Science, School of Mathematics and Physics, University of Science and Technology Beijing, Beijing 100083, China
| | - Fengping Wang
- Beijing Key Laboratory for Magneto-Photoelectrical Composite and Interface Science, School of Mathematics and Physics, University of Science and Technology Beijing, Beijing 100083, China
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Li X, Shi H, Gu Y, Cheng Q, Wang Y. Cobalt Element Effect of Ternary Mesoporous Cerium Lanthanum Solid Solution for the Catalytic Conversion of Methanol and CO 2 into Dimethyl Carbonate. Molecules 2022; 27:molecules27010270. [PMID: 35011502 PMCID: PMC8746974 DOI: 10.3390/molecules27010270] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/08/2021] [Revised: 12/24/2021] [Accepted: 12/28/2021] [Indexed: 11/16/2022]
Abstract
A citric acid ligand assisted self-assembly method is used for the synthesis of ternary mesoporous cerium lanthanum solid solution doped with metal elements (Co, Zr, Mg). Their textural property was characterized by X-ray diffraction, transmission electron microscopy, N2 adsorption-desorption, X-ray photoelectron spectroscopy and TPD techniques, and so on. The results of catalytic testing for synthesis of dimethyl carbonate (DMC) from CH3OH and CO2 indicated that the DMC yield reached 316 mmol/g on Ce-La-Co solid solution when the reaction temperature was 413 K and the reaction pressure was 8.0 MPa. It was found that Co had synergistic effect with La and Ce, doping of Co on the mesoporous Ce-La solid solution was helpful to increase the surface area of the catalyst, promote CO2 adsorption and activation, and improve the redox performance of solid solution catalyst. The conversion of Co2+ to Co3+ resulted in the continuous redox cycle between Ce4+ and Ce3+, and the oxygen vacancy content of the catalyst was increased. Studies have shown that the catalytic performance of Ce-La-Co solid solution is positively correlated with oxygen vacancy content. On this basis, the reaction mechanism of DMC synthesis from CO2 and CH3OH on the catalyst was speculated.
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Affiliation(s)
- Xu Li
- Key Laboratory of Green Chemical Technology and High Efficient Energy Saving of Hebei Province, Tianjin Key Laboratory of Chemical Process Safety, School of Chemical Engineering, Hebei University of Technology, Tianjin 300401, China; (X.L.); (Y.G.); (Y.W.)
| | - Hua Shi
- China Tianchen Engineering Corporation, Tianjin 300499, China
- Correspondence: (H.S.); (Q.C.)
| | - Yunhan Gu
- Key Laboratory of Green Chemical Technology and High Efficient Energy Saving of Hebei Province, Tianjin Key Laboratory of Chemical Process Safety, School of Chemical Engineering, Hebei University of Technology, Tianjin 300401, China; (X.L.); (Y.G.); (Y.W.)
| | - Qingyan Cheng
- Key Laboratory of Green Chemical Technology and High Efficient Energy Saving of Hebei Province, Tianjin Key Laboratory of Chemical Process Safety, School of Chemical Engineering, Hebei University of Technology, Tianjin 300401, China; (X.L.); (Y.G.); (Y.W.)
- Correspondence: (H.S.); (Q.C.)
| | - Yanji Wang
- Key Laboratory of Green Chemical Technology and High Efficient Energy Saving of Hebei Province, Tianjin Key Laboratory of Chemical Process Safety, School of Chemical Engineering, Hebei University of Technology, Tianjin 300401, China; (X.L.); (Y.G.); (Y.W.)
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Boytsova OV, Drozhzhin OA, Petukhov DI, Chumakova AV, Sobol AG, Beltyukov AN, Eliseev AA, Bosak AB. One-step synthesis of vanadium-doped anatase mesocrystals for Li-ion battery anodes. Nanotechnology 2021; 33:055603. [PMID: 34670202 DOI: 10.1088/1361-6528/ac317a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/31/2021] [Accepted: 10/20/2021] [Indexed: 06/13/2023]
Abstract
Here we report a successful one-step synthesis of vanadium-doped anatase mesocrystals by reactive annealing of NH4TiOF3/PEG2000 mesocrystal precursors with NH4VO3. The formation solid solution Ti1-xVxO2with vanadium content up tox = 25 at% inheriting the structure of mesocrystals is observed for the first time. The doping mechanism via vapor phase transport of vanadium is proposed. The Ti1-xVxO2mesocrystals exhibit improved specific capacity of 175 mAh g-1(compared to 150 mAh g-1for pure anatase phase) and decreased potential gap between charge and discharge processes.
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Affiliation(s)
- O V Boytsova
- Department of Materials Science, Lomonosov Moscow State University, 1-73 Leninskie Gory, Moscow, 119991, Russia
- Kurnakov Institute of General and Inorganic Chemistry RAS, Leninskii Prosp. 31, Moscow, 119071, Russia
| | - O A Drozhzhin
- Department of Chemistry, Lomonosov Moscow State University, 1-3 Leninskie Gory, Moscow, 119991, Russia
| | - D I Petukhov
- Department of Chemistry, Lomonosov Moscow State University, 1-3 Leninskie Gory, Moscow, 119991, Russia
| | - A V Chumakova
- European Synchrotron Radiation Facility, 78 Avenue des Martyrs, 38000 Grenoble, France
| | - A G Sobol
- Department of Materials Science, Lomonosov Moscow State University, 1-73 Leninskie Gory, Moscow, 119991, Russia
| | - A N Beltyukov
- Udmurt Federal Research Center of the Ural Brunch of Russian Academy of Sciences (UdmFRCof UB RAS), Izhevsk, st.them. Tatiana Baramzina 34, 426067, Russia
| | - A A Eliseev
- Department of Materials Science, Lomonosov Moscow State University, 1-73 Leninskie Gory, Moscow, 119991, Russia
| | - A B Bosak
- European Synchrotron Radiation Facility, 78 Avenue des Martyrs, 38000 Grenoble, France
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Zhang B, Fu S, Wang D, Jiao S, Zeng Z, Zhang X, Xu Z, Liu Y, Zhao C, Pan J, Liu D, Wang J. Synthesis and Enhanced Light Photocatalytic Activity of Modulating Band BiOBr XI 1-X Nanosheets. Nanomaterials (Basel) 2021; 11:2940. [PMID: 34835703 DOI: 10.3390/nano11112940] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/27/2021] [Revised: 10/26/2021] [Accepted: 10/28/2021] [Indexed: 11/17/2022]
Abstract
The photocatalysis technique has been proven to be a promising method to solve environmental pollution in situations of energy shortage, and has been intensively investigated in the field of pollutant degradation. In this work, a band structure-controlled solid solution of BiOBrXI1−X (x = 0.00, 0.05, 0.10, 0.15, 0.20, 1.00) with highly efficient light-driven photocatalytic activities was successfully synthesized via simple solvothermal methods. The phase composition, crystal structure, morphology, internal molecular vibration, optical properties, and energy band structure were characterized and analyzed by XRD, SEM, HRTEM, XPS, Raman, and UV Vis DRS. To evaluate the photocatalytic activity of BiOBrXI1−X, rhodamine B was selected as an organic pollutant. In particular, BiOBr0.15I0.85 displayed significantly enhanced photocatalytic activity by virtue of modulating the energy band position, optimizing redox potentials, and accelerating carrier separation. Moreover, the enhancement mechanism was elucidated on the basis of band structure engineering, which provides ideas for the design of highly active photocatalysts for practical application in the fields of environmental issues and energy conservation.
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Thandorn T, Tsakiropoulos P. The Effect of Boron on the Microstructure and Properties of Refractory Metal Intermetallic Composites (RM(Nb)ICs) Based on Nb-24Ti-xSi (x = 16, 17 or 18 at.%) with Additions of Al, Cr or Mo. Materials (Basel) 2021; 14:6101. [PMID: 34683690 PMCID: PMC8537113 DOI: 10.3390/ma14206101] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/21/2021] [Revised: 09/27/2021] [Accepted: 10/04/2021] [Indexed: 11/24/2022]
Abstract
This paper is about metallic ultra-high temperature materials, in particular, refractory metal intermetallic composites based on Nb, i.e., RM(Nb)ICs, with the addition of boron, which are compared with refractory metal high entropy alloys (RHEAs) or refractory metal complex concentrated alloys (RCCAs). We studied the effect of B addition on the density, macrosegregation, microstructure, hardness and oxidation of four RM(Nb)IC alloys, namely the alloys TT2, TT3, TT4 and TT8 with nominal compositions (at.%) Nb-24Ti-16Si-5Cr-7B, Nb-24Ti-16Si-5Al-7B, Nb-24Ti-18Si-5Al-5Cr-8B and Nb-24Ti-17Si-3.5Al-5Cr-6B-2Mo, respectively. The alloys made it possible to compare the effect of B addition on density, hardness or oxidation with that of Ge or Sn addition. The alloys were made using arc melting and their microstructures were characterised in the as cast and heat-treated conditions. The B macrosegregation was highest in TT8. The macrosegregation of Si or Ti increased with the addition of B and was lowest in TT8. The alloy TT8 had the lowest density of 6.41 g/cm3 and the highest specific strength at room temperature, which was also higher than that of RCCAs and RHEAs. The Nbss and T2 silicide were stable in the alloys TT2 and TT3, whereas in TT4 and TT8 the stable phases were the Nbss and the T2 and D88 silicides. Compared with the Ge or Sn addition in the same reference alloy, the B and Ge addition was the least and most effective at 800 °C (i.e., in the pest regime), when no other RM was present in the alloy. Like Ge or Sn, the B addition in TT2, TT3 and TT4 did not suppress scale spallation at 1200 °C. Only the alloy TT8 did not pest and its scales did not spall off at 800 and 1200 °C. The macrosegregation of Si and Ti, the chemical composition of Nbss and T2, the microhardness of Nbss and the hardness of alloys, and the oxidation of the alloys at 800 and 1200 °C were also viewed from the perspective of the alloy design methodology NICE and relationships with the alloy or phase parameters VEC, δ and Δχ. The trends of these parameters and the location of alloys and phases in parameter maps were found to be in agreement with NICE.
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Affiliation(s)
- Tophan Thandorn
- Department of Materials Science and Engineering, School of Science, Mae Fah Luang University, Chiang Rai 57100, Thailand;
- Department of Materials Science and Engineering, Sir Robert Hadfield Building, The University of Sheffield, Sheffield S1 3JD, UK
| | - Panos Tsakiropoulos
- Department of Materials Science and Engineering, Sir Robert Hadfield Building, The University of Sheffield, Sheffield S1 3JD, UK
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Joele M, Matizamhuka WR. A Review on the High Temperature Strengthening Mechanisms of High Entropy Superalloys (HESA). Materials (Basel) 2021; 14:5835. [PMID: 34640232 PMCID: PMC8510092 DOI: 10.3390/ma14195835] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/02/2021] [Revised: 09/08/2021] [Accepted: 09/13/2021] [Indexed: 11/16/2022]
Abstract
The studies following HEA inceptions were apparently motivated to search for single-phase solid solution over intermetallic phases, accordingly made possible by the concept of high configurational entropy. However, it was realised that the formation of intermetallic phases in HEAs is prevalent due to other criterions that determine stable phases. Nonetheless, recent efforts have been directed towards attributes of microstructural combinations. In this viewpoint, the techniques used to predict microstructural features and methods of microstructural characterisation are elucidated in HESA fields. The study further analyses shortcomings regarding the design approaches of HESAs. A brief history is given into how HESAs were developed since their birth, to emphasize the evaluation techniques used to elucidate high temperature properties of HESAs, and the incentive thereof that enabled further pursuit of HESAs in the direction of optimal microstructure and composition. The theoretical models of strengthening mechanisms in HEAs are explained. The impact of processing route on the HESAs performance is analysed from previous studies. Thereafter, the future of HESAs in the market is conveyed from scientific opinion. Previous designs of HEAs/HESAs were more based on evaluation experiments, which lead to an extended period of research and considerable use of resources; currently, more effort is directed towards computational and theoretical methods to accelerate the exploration of huge HEA composition space.
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Affiliation(s)
- Malefane Joele
- Department of Chemical and Metallurgical Engineering, Vaal University of Technology, Vanderbijlpark 1911, South Africa;
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Gorniewicz D, Przygucki H, Kopec M, Karczewski K, Jóźwiak S. TiCoCrFeMn (BCC + C14) High-Entropy Alloy Multiphase Structure Analysis Based on the Theory of Molecular Orbitals. Materials (Basel) 2021; 14:5285. [PMID: 34576509 DOI: 10.3390/ma14185285] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/12/2021] [Revised: 09/09/2021] [Accepted: 09/11/2021] [Indexed: 11/17/2022]
Abstract
High-entropy alloys (HEA) are a group of modern, perspective materials that have been intensively developed in recent years due to their superior properties and potential applications in many fields. The complexity of their chemical composition and the further interactions of main elements significantly inhibit the prediction of phases that may form during material processing. Thus, at the design stage of HEA fabrication, the molecular orbitals theory was proposed. In this method, the connection of the average strength of covalent bonding between the alloying elements (Bo parameter) and the average energy level of the d-orbital (parameter Md) enables for a preliminary assessment of the phase structure and the type of lattice for individual components in the formed alloy. The designed TiCoCrFeMn alloy was produced by the powder metallurgy method, preceded by mechanical alloying of the initial elementary powders and at the temperature of 1050 °C for 60 s. An ultra-fine-grained structured alloy was homogenized at 1000 °C for 1000 h. The X-ray diffraction and scanning electron microscopy analysis confirmed the correctness of the methodology proposed as the assumed phase structure consisted of the body-centered cubic (BCC) solid solution and the C14 Laves phase was obtained.
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Tubtimsri S, Weerapol Y. Improvement in Solubility and Absorption of Nifedipine Using Solid Solution: Correlations between Surface Free Energy and Drug Dissolution. Polymers (Basel) 2021; 13:polym13172963. [PMID: 34503003 PMCID: PMC8434079 DOI: 10.3390/polym13172963] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2021] [Revised: 08/29/2021] [Accepted: 08/30/2021] [Indexed: 11/16/2022] Open
Abstract
Ternary solid solutions composed of nifedipine (NDP), amino methacrylate copolymer (AMCP), and polysorbate (PS) 20, 60, or 65 were prepared using a solvent evaporation method. The dissolution profiles of NDP were used to study the effect of the addition of polysorbate based on hydrophilic properties. A solid solution of NDP and AMCP was recently developed; however, the dissolution of NDP was <70%. In the present study, polysorbate was added to improve the dissolution of the drug by altering its hydrophilicity. The suitable formulation contained NDP and AMCP at a ratio of 1:4 and polysorbate at a concentration of 0.1%, 0.3%, or 0.6%. Differential scanning calorimetry and powder X-ray diffraction were used to examine the solid solutions. No peak representing crystalline NDP was observed in any solid solution samples, suggesting that the drug was molecularly dispersed in AMCP. The NDP dissolution from NDP powder and solid solution without PS were 16.82% and 58.19%, respectively. The highest dissolution of NDP of approximately 95.25% was noted at 120 min for the formulation containing 0.6% PS20. Linear correlations were observed between the surface free energy and percentages of dissolved NDP (R2 = 0.7115–0.9315). Cellular uptake across Caco-2 was selected to determine the drug permeability. The percentages of cellular uptake from the NDP powder, solid solution without and with PS20 were 0.25%, 3.60%, and 7.27%, respectively.
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Karoblis D, Diliautas R, Mazeika K, Baltrunas D, Niaura G, Talaikis M, Beganskiene A, Zarkov A, Kareiva A. Lanthanum and Manganese Co-Doping Effects on Structural, Morphological, and Magnetic Properties of Sol-Gel Derived BiFeO 3. Materials (Basel) 2021; 14:ma14174844. [PMID: 34500933 PMCID: PMC8432725 DOI: 10.3390/ma14174844] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/26/2021] [Revised: 08/19/2021] [Accepted: 08/23/2021] [Indexed: 11/16/2022]
Abstract
In this work, lanthanum and manganese co-substitution effects on different properties of bismuth ferrite solid solutions Bi1-xLaxFe0.85Mn0.15O3 (x from 0 to 1) prepared by a sol-gel synthetic approach have been investigated. It was observed that the structural, morphological, and magnetic properties of obtained specimens are influenced by the amount of introduced La3+ ions. Surprisingly, only the compound with a composition of BiFe0.85Mn0.15O3 was not monophasic, and the presence of neighboring phases was determined from X-ray diffraction analysis and Mössbauer measurements. Structural transitions from orthorhombic to cubic and back to orthorhombic were also observed depending on the La3+ amount. Antiferromagnetic behaviour was observed for all of the samples, with the highest magnetisation values for Bi0.5La0.5Fe0.85Mn0.15O3. Additionally, structural attributes and morphological features were evaluated by Raman spectroscopy and scanning electron microscopy (SEM), respectively.
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Affiliation(s)
- Dovydas Karoblis
- Institute of Chemistry, Vilnius University, Naugarduko 24, LT-03225 Vilnius, Lithuania; (D.K.); (R.D.); (A.B.); (A.Z.)
| | - Ramunas Diliautas
- Institute of Chemistry, Vilnius University, Naugarduko 24, LT-03225 Vilnius, Lithuania; (D.K.); (R.D.); (A.B.); (A.Z.)
| | - Kestutis Mazeika
- Center of Physical Sciences and Technology, LT-02300 Vilnius, Lithuania; (K.M.); (D.B.); (G.N.)
| | - Dalis Baltrunas
- Center of Physical Sciences and Technology, LT-02300 Vilnius, Lithuania; (K.M.); (D.B.); (G.N.)
| | - Gediminas Niaura
- Center of Physical Sciences and Technology, LT-02300 Vilnius, Lithuania; (K.M.); (D.B.); (G.N.)
- Institute of Chemical Physics, Faculty of Physics, Vilnius University, Sauletekio Ave. 3,LT-10257 Vilnius, Lithuania
| | - Martynas Talaikis
- Department of Bioelectrochemistry and Biospectroscopy, Institute of Biochemistry, Life Sciences Center, Vilnius University, LT-10257 Vilnius, Lithuania;
| | - Aldona Beganskiene
- Institute of Chemistry, Vilnius University, Naugarduko 24, LT-03225 Vilnius, Lithuania; (D.K.); (R.D.); (A.B.); (A.Z.)
| | - Aleksej Zarkov
- Institute of Chemistry, Vilnius University, Naugarduko 24, LT-03225 Vilnius, Lithuania; (D.K.); (R.D.); (A.B.); (A.Z.)
| | - Aivaras Kareiva
- Institute of Chemistry, Vilnius University, Naugarduko 24, LT-03225 Vilnius, Lithuania; (D.K.); (R.D.); (A.B.); (A.Z.)
- Correspondence:
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63
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Cherniushok O, Parashchuk T, Tobola J, Luu SDN, Pogodin A, Kokhan O, Studenyak I, Barchiy I, Piasecki M, Wojciechowski KT. Entropy-Induced Multivalley Band Structures Improve Thermoelectric Performance in p-Cu 7P(S xSe 1-x) 6 Argyrodites. ACS Appl Mater Interfaces 2021; 13:39606-39620. [PMID: 34387484 DOI: 10.1021/acsami.1c11193] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Searching for novel low-cost and eco-friendly materials for energy conversion is a good way to provide widespread utilization of thermoelectric technologies. Herein, we report the thermal behavior, phase equilibria data, and thermoelectric properties for the promising argyrodite-based Cu7P(SxSe1-x)6 thermoelectrics. Alloying of Cu7PSe6 with Cu7PS6 provides a continuous solid solution over the whole compositional range, as shown in the proposed phase diagram for the Cu7PS6-Cu7PSe6 system. As a member of liquid-like materials, the investigated Cu7P(SxSe1-x)6 solid solutions possess a dramatically low lattice thermal conductivity, as low as ∼0.2-0.3 W m-1 K-1, over the entire temperature range. Engineering the configurational entropy of the material by introducing more elements stabilizes the thermoelectrically beneficial high-symmetry γ-phase and promotes the multivalley electronic structure of the valence band. As a result, a remarkable improvement of the Seebeck coefficient and a reduction of electrical resistivity were observed for the investigated alloys. The combined effect of the extremely low lattice thermal conductivity and enhanced power factor leads to the significant enhancement of the thermoelectric figure of merit ZT up to ∼0.75 at 673 K for the Cu7P(SxSe1-x)6 (x = 0.5) sample with the highest configurational entropy, which is around twice higher compared with the pure selenide and almost four times higher than sulfide. This work not only demonstrates the large potential of Cu7P(SxSe1-x)6 materials for energy conversion but also promotes sulfide argyrodites as earth-abundant and environmentally friendly materials for energy conversion.
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Affiliation(s)
- Oleksandr Cherniushok
- Thermoelectric Research Laboratory, Department of Inorganic Chemistry, Faculty of Materials Science and Ceramics, AGH University of Science and Technology, 30 Mickiewicza Avenue, 30-059 Krakow, Poland
- Lukasiewicz Research Network, Krakow Institute of Technology, Zakopianska 73, 30-418 Krakow, Poland
| | - Taras Parashchuk
- Thermoelectric Research Laboratory, Department of Inorganic Chemistry, Faculty of Materials Science and Ceramics, AGH University of Science and Technology, 30 Mickiewicza Avenue, 30-059 Krakow, Poland
- Lukasiewicz Research Network, Krakow Institute of Technology, Zakopianska 73, 30-418 Krakow, Poland
| | - Janusz Tobola
- Faculty of Physics and Applied Computer Science, AGH University of Science and Technology, 30-059 Krakow, Poland
| | - Son D N Luu
- Lukasiewicz Research Network, Krakow Institute of Technology, Zakopianska 73, 30-418 Krakow, Poland
- Institute of Research and Development, Duy Tan University, Da Nang 550000, Viet Nam
| | - Artem Pogodin
- Uzhhorod National University, Pidhirna 46, 88000 Uzhhorod, Ukraine
| | - Oleksandr Kokhan
- Uzhhorod National University, Pidhirna 46, 88000 Uzhhorod, Ukraine
| | - Ihor Studenyak
- Uzhhorod National University, Pidhirna 46, 88000 Uzhhorod, Ukraine
| | - Igor Barchiy
- Uzhhorod National University, Pidhirna 46, 88000 Uzhhorod, Ukraine
| | - Michal Piasecki
- Theoretical Physics Department, Jan Długosz University, Armii Krajowej 13/15, 42200 Częstochowa, Poland
| | - Krzysztof T Wojciechowski
- Thermoelectric Research Laboratory, Department of Inorganic Chemistry, Faculty of Materials Science and Ceramics, AGH University of Science and Technology, 30 Mickiewicza Avenue, 30-059 Krakow, Poland
- Lukasiewicz Research Network, Krakow Institute of Technology, Zakopianska 73, 30-418 Krakow, Poland
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64
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Wang G, Mu X, Li J, Zhan Q, Qian Y, Mu X, Li L. Light-Induced Nonoxidative Coupling of Methane Using Stable Solid Solutions. Angew Chem Int Ed Engl 2021; 60:20760-20764. [PMID: 34292637 DOI: 10.1002/anie.202108870] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2021] [Indexed: 11/10/2022]
Abstract
Achieving efficient and direct conversion of methane under mild conditions is of great significance for innovations in the chemical industry. However, the efficiency and lifetime of most catalysts remain too far from practical requirements, since it is difficult to break the first C-H bond of methane as well as to suppress the following complete dehydrogenation (or overoxidation) and the resulting carbonaceous deposition (or CO2 ). Here, we report that wurtzite GaN:ZnO solid solutions exhibit unique and unprecedented photocatalytic performances for the nonoxidative coupling of methane at room temperature, exclusively generating ethane with nearly stoichiometric H2 . High conversion rate (>330 μmol g-1 h-1 ), long-term stability (>70 h), and superior coke-resistance were achieved. At 293 K, the methane conversion exceeds 7 %, comparable to the equilibrium conversion of thermal catalysis at 910 K. Mechanistic studies revealed that the N-ZnGa -ON units and the absence of acid sites on the surface played crucial roles in reactivity and coke resistance, respectively.
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Affiliation(s)
- Guangming Wang
- State Key Laboratory of Inorganic Synthesis and Preparative Chemistry, College of Chemistry, Jilin University, Changchun, 130012, P.R. China
| | - Xiaowei Mu
- State Key Laboratory of Inorganic Synthesis and Preparative Chemistry, College of Chemistry, Jilin University, Changchun, 130012, P.R. China.,College of Chemistry, Jilin University, Changchun, 130012, P.R. China
| | - Jiayang Li
- State Key Laboratory of Inorganic Synthesis and Preparative Chemistry, College of Chemistry, Jilin University, Changchun, 130012, P.R. China
| | - Qingyun Zhan
- State Key Laboratory of Inorganic Synthesis and Preparative Chemistry, College of Chemistry, Jilin University, Changchun, 130012, P.R. China
| | - Yumeng Qian
- State Key Laboratory of Inorganic Synthesis and Preparative Chemistry, College of Chemistry, Jilin University, Changchun, 130012, P.R. China
| | - Xiaoyue Mu
- College of Chemistry, Jilin University, Changchun, 130012, P.R. China
| | - Lu Li
- State Key Laboratory of Inorganic Synthesis and Preparative Chemistry, College of Chemistry, Jilin University, Changchun, 130012, P.R. China.,College of Chemistry, Jilin University, Changchun, 130012, P.R. China
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65
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Gulyaeva Y, Alekseeva Bykova M, Bulavchenko O, Kremneva A, Saraev A, Gerasimov E, Selishcheva S, Kaichev V, Yakovlev V. Ni-Cu High-Loaded Sol-Gel Catalysts for Dehydrogenation of Liquid Organic Hydrides: Insights into Structural Features and Relationship with Catalytic Activity. Nanomaterials (Basel) 2021; 11:2017. [PMID: 34443848 DOI: 10.3390/nano11082017] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/16/2021] [Revised: 08/04/2021] [Accepted: 08/05/2021] [Indexed: 01/24/2023]
Abstract
The heightened interest in liquid organic hydrogen carriers encourages the development of catalysts suitable for multicycle use. To ensure high catalytic activity and selectivity, the structure-reactivity relationship must be extensively investigated. In this study, high-loaded Ni-Cu catalysts were considered for the dehydrogenation of methylcyclohexane. The highest conversion of 85% and toluene selectivity of 70% were achieved at 325 °C in a fixed-bed reactor using a catalyst with a Cu/Ni atomic ratio of 0.23. To shed light on the relationship between the structural features and catalytic performance, the catalysts were thoroughly studied using a wide range of advanced physicochemical tools. The activity and selectivity of the proposed catalysts are related to the uniformity of Cu distribution and its interaction with Ni via the formation of metallic solid solutions. The method of introduction of copper in the catalyst plays a crucial role in the effectiveness of the interaction between the two metals.
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66
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Zhong J, Zhuo Y, Du F, Zhang H, Zhao W, Brgoch J. Efficient and Tunable Luminescence in Ga 2-xIn xO 3:Cr 3+ for Near-Infrared Imaging. ACS Appl Mater Interfaces 2021; 13:31835-31842. [PMID: 34185499 DOI: 10.1021/acsami.1c05949] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Broadband near-infrared (NIR) emitting materials are in great demand as next-generation smart NIR light sources. In this work, a Cr3+-substituted phosphor capable of efficiently converting visible to NIR light is developed through the solid solution, Ga2-xInxO3:Cr3+ (0 ≤ x ≤ 0.5). The compounds were prepared using high-temperature solid-state synthesis, and the crystal and electronic structure, morphology, site preference, and photoluminescence properties are studied. The photoluminescence results demonstrate a high quantum yield (88%) and impressive absorption efficiency (50%) when x = 0.4. The NIR emission is tunable across a wide range (713-820 nm) depending on the value of x. Moreover, fabricating a prototype of a phosphor-converted NIR light-emitting diode (LED) device using 450 nm LED and the [(Ga1.57Cr0.03)In0.4]O3 phosphor showed an output power that reached 40.4 mW with a photoelectric conversion efficiency of 25% driven by a current of 60 mA, while the resulting device was able to identify damaged produce that was undetectable using visible light. These results demonstrate the outstanding potential of this phosphor for NIR LED imaging applications.
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Affiliation(s)
- Jiyou Zhong
- School of Physics and Optoelectronic Engineering, Guangdong University of Technology, Guangzhou 510006, China
| | - Ya Zhuo
- Department of Chemistry, University of Houston, Houston, Texas 77204, United States
| | - Fu Du
- School of Metallurgy and Chemistry Engineering, Jiangxi University of Science and Technology, Ganzhou 341000, China
| | - Hongshi Zhang
- School of Physics and Optoelectronic Engineering, Guangdong University of Technology, Guangzhou 510006, China
| | - Weiren Zhao
- School of Physics and Optoelectronic Engineering, Guangdong University of Technology, Guangzhou 510006, China
| | - Jakoah Brgoch
- Department of Chemistry, University of Houston, Houston, Texas 77204, United States
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67
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Straus DB, Cava RJ. Generalizing the Chiral Self-Assembly of Spheres and Tetrahedra to Non-Spherical and Polydisperse Molecules in (C 70) x(C 60) 1-x(SnI 4) 2. Nano Lett 2021; 21:4753-4756. [PMID: 34014669 DOI: 10.1021/acs.nanolett.1c01181] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
We describe the spontaneous chiral self-assembly of C70 with SnI4 as well as a mixture of C60 and C70 with SnI4. Macroscopic single crystals with the formula (C70)x(C60)1-x(SnI4)2 (x = 0-1) are reported. C60, which is spherical, and C70, which is ellipsoidal, form a solid solution in these crystals, and the cubic lattice parameter of the chiral phase linearly increases as x grows from 0 to 1 in accordance with Vegard's law. Our results demonstrate that nonspherical particles and polydispersity are not an impediment to the growth of chiral crystals from high-symmetry achiral precursors, providing a route to assemble achiral particles including colloidal nanocrystals and engineered nanostructures into chiral materials without the need to use external templates or forces.
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Affiliation(s)
- Daniel B Straus
- Department of Chemistry, Princeton University, Princeton, New Jersey 08544, United States
| | - Robert J Cava
- Department of Chemistry, Princeton University, Princeton, New Jersey 08544, United States
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68
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Zhang Q, Huang R, Zhang X, Cao T, Xue Y, Li X. Deformation Mechanisms and Remarkable Strain Hardening in Single-Crystalline High-Entropy-Alloy Micropillars/Nanopillars. Nano Lett 2021; 21:3671-3679. [PMID: 33756077 DOI: 10.1021/acs.nanolett.1c00444] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
There have been very limited studies on plastic deformation mechanisms in single-crystalline high-entropy alloys (HEAs) with body-centered cubic (BCC) phases. We performed in situ uniaxial compression on single-crystalline BCC AlCrFeCoNi micropillars/nanopillars with three orientations (including [100], [110], and [111]) and diameters of 270-1583 nm, inside a scanning electron microscope. The experimental results showed the significant size effects on yield/flow stress and the remarkable strain hardening in these HEA micropillars/nanopillars. Especially, HEA micropillars/nanopillars with ⟨100⟩ orientation exhibited higher strain hardening exponents than BCC pure metals and Al0.7CrCoFeNi counterparts. A combination of transmission electron microscopy observations and large-scale atomistic simulations revealed that dislocation slip, reaction, tangling and accumulation, and solid solution effects are responsible for the observed size effects on yield/flow stress and remarkable strain hardening, but these dislocation mechanisms are dependent on nanopillar orientation. Our present study sheds light on the underlying deformation mechanisms in BCC HEA single crystals.
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Affiliation(s)
- Qian Zhang
- Center for Advanced Mechanics and Materials, Applied Mechanics Laboratory, Department of Engineering Mechanics, Tsinghua University, Beijing 100084, China
| | - Ruirui Huang
- Center for Advanced Mechanics and Materials, Applied Mechanics Laboratory, Department of Engineering Mechanics, Tsinghua University, Beijing 100084, China
| | - Xuan Zhang
- Center for Advanced Mechanics and Materials, Applied Mechanics Laboratory, Department of Engineering Mechanics, Tsinghua University, Beijing 100084, China
| | - Tangqing Cao
- School of Materials Science and Engineering, Beijing Institute of Technology, Beijing 100081, China
| | - Yunfei Xue
- School of Materials Science and Engineering, Beijing Institute of Technology, Beijing 100081, China
| | - Xiaoyan Li
- Center for Advanced Mechanics and Materials, Applied Mechanics Laboratory, Department of Engineering Mechanics, Tsinghua University, Beijing 100084, China
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69
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Bulavchenko OA, Afonasenko TN, Osipov AR, Pochtar' AA, Saraev AA, Vinokurov ZS, Gerasimov EY, Tsybulya SV. The Formation of Mn-Ce Oxide Catalysts for CO Oxidation by Oxalate Route: The Role of Manganese Content. Nanomaterials (Basel) 2021; 11:988. [PMID: 33921273 DOI: 10.3390/nano11040988] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/15/2021] [Revised: 04/02/2021] [Accepted: 04/07/2021] [Indexed: 11/17/2022]
Abstract
The Mn-Ce oxide catalysts active in the oxidation of CO were studied by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), temperature-programmed reduction (TPR), transition electron microscopy (TEM), energy dispersive X-Ray (EDX), and a differential dissolution technique. The Mn-Ce catalysts were prepared by thermal decomposition of oxalates by varying the Mn:Ce ratio. The nanocrystalline oxides with a fluorite structure and particle sizes of 4–6 nm were formed. The introduction of manganese led to a reduction of the oxide particle size, a decrease in the surface area, and the formation of a MnyCe1−yO2−δ solid solution. An increase in the manganese content resulted in the formation of manganese oxides such as Mn2O3, Mn3O4, and Mn5O8. The catalytic activity as a function of the manganese content had a volcano-like shape. The best catalytic performance was exhibited by the catalyst containing ca. 50 at.% Mn due to the high specific surface area, the formation of the solid solution, and the maximum content of the solid solution.
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70
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Serghiou G, Reichmann HJ, Odling N, Spektor K, Pakhomova A, Crichton WA, Konôpková Z. An Unexpected Cubic Symmetry in Group IV Alloys Prepared Using Pressure and Temperature. Angew Chem Int Ed Engl 2021; 60:9009-9014. [PMID: 33527580 PMCID: PMC8049010 DOI: 10.1002/anie.202016179] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2020] [Indexed: 11/28/2022]
Abstract
The cubic diamond (Fd3‾m) group IVA element Si has been the material driver of the electronics industry since its inception. We report synthesis of a new cubic (Im3‾m) group IVA material, a GeSn solid solution, upon heating Ge and Sn at pressures from 13 to 28 GPa using double‐sided diamond anvil laser‐heating and large volume press methods. Both methods were coupled with in situ angle dispersive X‐ray diffraction characterization. The new material substantially enriches the seminal group IVA alloy materials landscape by introducing an eightfold coordinated cubic symmetry, which markedly expands on the conventional tetrahedrally coordinated cubic one. This cubic solid solution is formed, despite Ge never adopting the Im3‾m symmetry, melting inhibiting subsequent Im3‾m formation and reactant Ge and Sn having unlike crystal structures and atomic radii at all these pressures. This is hence achieved without adherence to conventional formation criteria and routes to synthesis. This advance creates fertile avenues for new materials development.
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Affiliation(s)
- George Serghiou
- School of Engineering, University of Edinburgh, Kings Buildings, Robert Stevenson Road, Edinburgh, EH9 3FB, Scotland, UK
| | | | - Nicholas Odling
- School of Geosciences, University of Edinburgh, Kings Buildings, West Mains Road, Edinburgh, EH9 3JW, Scotland, UK
| | - Kristina Spektor
- The European Synchrotron, ESRF, 71 avenue des Martyrs, 38000, Grenoble, France
| | - Anna Pakhomova
- Deutsches Elektronen-Synchrotron, DESY, 22607, Hamburg, Germany
| | - Wilson A Crichton
- The European Synchrotron, ESRF, 71 avenue des Martyrs, 38000, Grenoble, France
| | - Zuzana Konôpková
- Deutsches Elektronen-Synchrotron, DESY, 22607, Hamburg, Germany.,European XFEL GmbH, Holzkoppel 4, 22869, Schenefeld, Germany
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71
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Wu Y, Su X, Yang D, Zhang Q, Tang X. Boosting Thermoelectric Properties of AgBi 3(Se yS 1-y) 5 Solid Solution via Entropy Engineering. ACS Appl Mater Interfaces 2021; 13:4185-4191. [PMID: 33433997 DOI: 10.1021/acsami.0c19387] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
AgBi3S5 is an environmentally friendly n-type thermoelectric material composed of earth-abundant and nontoxic elements. It has a complex monoclinic structure with distorted NaCl-type fragments, which provide its intrinsically low thermal conductivity. However, poor electrical properties limit its overall performance. Configurational entropy engineering is an effective method to enhance thermoelectric properties. With the increase of configurational entropy, phonon point defect scattering is amplified, yielding lower lattice thermal conductivity, while the structure symmetry can also be improved, which leads to the enhanced electrical transport property. In this study, we combine carrier modulation and entropy engineering, utilizing melting-annealing and spark plasma sintering, to synthesize a series of AgBi3(SeyS1-y)5.08 bulks. Se substitution effectively increases the configurational entropy and thus dramatically decreases the thermal conductivity. Moreover, anion deficiency modulation effectively optimizes the carrier concentration and the electrical transport properties. Due to a power factor of 2.7 μW/(cm·K2) and a low thermal conductivity of 0.45 W/(m·K) at 723 K, the AgBi3(Se0.9S0.1)5.08 sample possesses the highest ZT of 0.42 at 723 K, nearly double the value of AgBi3S5.08 or pristine AgBi3S5. Our work demonstrates that apart from carrier optimization, entropy engineering opens a new avenue for enhancing the thermoelectric properties of a given material.
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Affiliation(s)
- Yutian Wu
- State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, Wuhan University of Technology, Wuhan 430070, China
| | - Xianli Su
- State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, Wuhan University of Technology, Wuhan 430070, China
| | - Dongwang Yang
- State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, Wuhan University of Technology, Wuhan 430070, China
| | - Qingjie Zhang
- State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, Wuhan University of Technology, Wuhan 430070, China
| | - Xinfeng Tang
- State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, Wuhan University of Technology, Wuhan 430070, China
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72
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Wang Y, Kang Y, Zhu H, Liu G, Irvine JTS, Xu X. Perovskite Oxynitride Solid Solutions of LaTaON 2-CaTaO 2N with Greatly Enhanced Photogenerated Charge Separation for Solar-Driven Overall Water Splitting. Adv Sci (Weinh) 2021; 8:2003343. [PMID: 33511021 PMCID: PMC7816695 DOI: 10.1002/advs.202003343] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/01/2020] [Indexed: 06/12/2023]
Abstract
The search for solar-driven photocatalysts for overall water splitting has been actively pursued. Although metal oxynitrides with metal d0/d10-closed shell configuration are very promising candidates in terms of their visible light absorption, they usually suffer from serious photo-generated charge recombination and thus, little photoactivity. Here, by forming their solid solutions of LaTaON2 and CaTaO2N, which are traditionally considered to be inorganic yellow-red pigments but have poor photocatalytic activity, a class of promising solar-driven photocatalysts La1- x Ca x TaO1+yN2- y (0 ≤ x, y ≤ 1) are explored. In particular, the optimal photocatalyst with x = 0.9 has the ability of realizing overall water splitting with stoichiometric H2/O2 ratio under the illumination of both AM1.5 simulated solar light and visible light. The modulated key parameters including band structure, Ta bonding environment, defects concentration, and band edge alignments revealed in La0.1Ca0.9TaO1+ y N2- y have substantially promoted the separation of photogenerated charge carriers with sufficient energetics for water oxidation and reduction reactions. The results obtained in this study provide an important candidate for designing efficient solar-driven photocatalysts for overall water splitting.
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Affiliation(s)
- Yawei Wang
- Clinical and Central LabPutuo People's HospitalShanghai Key Lab of Chemical Assessment and SustainabilitySchool of Chemical Science and EngineeringTongji UniversityShanghaiChina
| | - Yuyang Kang
- Shenyang National Laboratory for Materials ScienceInstitute of Metal ResearchChinese Academy of Sciences72 Wenhua RoadShenyang110016China
| | - Huaze Zhu
- Shenyang National Laboratory for Materials ScienceInstitute of Metal ResearchChinese Academy of Sciences72 Wenhua RoadShenyang110016China
| | - Gang Liu
- Shenyang National Laboratory for Materials ScienceInstitute of Metal ResearchChinese Academy of Sciences72 Wenhua RoadShenyang110016China
- School of Materials Science and EngineeringUniversity of Science and Technology of China72 Wenhua RoadShenyang110016China
| | | | - Xiaoxiang Xu
- Clinical and Central LabPutuo People's HospitalShanghai Key Lab of Chemical Assessment and SustainabilitySchool of Chemical Science and EngineeringTongji UniversityShanghaiChina
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Wang M, Chen D, Li N, Xu Q, Li H, He J, Lu J. Nanocage-Shaped Co 3- x Zr x O 4 Solid-Solution Supports Loaded with Pt Nanoparticles as Effective Catalysts for the Enhancement of Toluene Oxidation. Small 2020; 16:e2005715. [PMID: 33241643 DOI: 10.1002/smll.202005715] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/14/2020] [Indexed: 06/11/2023]
Abstract
Nanocage-shaped Co3- x Zrx O4 solid-solution supports and the corresponding platinum loaded nanocomposites, yPt/Co3- x Zrx O4 (x =0.27, 0.50, 0.69; y = 0.5, 1.0, 2.0 wt.%), are successfully fabricated via a Cu2 O nanocube hard template method and a glycol reduction method, respectively. The hollow nanocage structures obviously improve surface areas; moreover, the Zr doping forms the Co3- x Zrx O4 solid-solution supports, and the corresponding yPt/Co3- x Zrx O4 catalysts promote the enhancement of catalytic performance. Catalytic activity toward toluene combustion is enhanced for the 2.0 wt% Pt/Co2.73 Zr0.27 O4 catalyst. The catalysts are characterized using multiple techniques. Pt nanoparticles are uniformly dispersed across the Co2.73 Zr0.27 O4 nanocage surface. The 2.0 wt% Pt/Co2.73 Zr0.27 O4 catalyst exhibits the highest catalytic activity among all the samples and demonstrates good stability, with 90% toluene conversion obtained at a temperature of 165 °C. The same catalyst accomplishes full toluene oxidation at 180 °C, at a weight hourly space velocity of 36 000 mL h-1 g-1 . The apparent activation energy (Ea ) over the yPt/Co2.73 Zr0.27 O4 samples are significantly lower than those over the Co3- x Zrx O4 supports, with the 2.0 wt% Pt/Co2.73 Zr0.27 O4 catalyst exhibiting the lowest Ea value. These findings demonstrate the potential of the 2.0 wt% Pt/Co2.73 Zr0.27 O4 catalyst as a promising catalyst toward atmospheric toluene removal.
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Affiliation(s)
- Mengmeng Wang
- College of Chemistry, Chemical Engineering and Materials Science, Collaborative Innovation Center of Suzhou Nano Science and Technology, Soochow University, Suzhou, 215123, P. R. China
| | - Dongyun Chen
- College of Chemistry, Chemical Engineering and Materials Science, Collaborative Innovation Center of Suzhou Nano Science and Technology, Soochow University, Suzhou, 215123, P. R. China
| | - Najun Li
- College of Chemistry, Chemical Engineering and Materials Science, Collaborative Innovation Center of Suzhou Nano Science and Technology, Soochow University, Suzhou, 215123, P. R. China
| | - Qingfeng Xu
- College of Chemistry, Chemical Engineering and Materials Science, Collaborative Innovation Center of Suzhou Nano Science and Technology, Soochow University, Suzhou, 215123, P. R. China
| | - Hua Li
- College of Chemistry, Chemical Engineering and Materials Science, Collaborative Innovation Center of Suzhou Nano Science and Technology, Soochow University, Suzhou, 215123, P. R. China
| | - Jinghui He
- College of Chemistry, Chemical Engineering and Materials Science, Collaborative Innovation Center of Suzhou Nano Science and Technology, Soochow University, Suzhou, 215123, P. R. China
| | - Jianmei Lu
- College of Chemistry, Chemical Engineering and Materials Science, Collaborative Innovation Center of Suzhou Nano Science and Technology, Soochow University, Suzhou, 215123, P. R. China
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Yoshikawa S, Watanabe S, Yamamoto Y, Kaneko F. Binary Phase Behavior of 1,3-Distearoyl-2-oleoyl- sn-glycerol (SOS) and Trilaurin (LLL). Molecules 2020; 25:E5313. [PMID: 33202625 DOI: 10.3390/molecules25225313] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2020] [Revised: 11/11/2020] [Accepted: 11/12/2020] [Indexed: 11/16/2022] Open
Abstract
This paper reports the precise analysis of the eutectic mixing behavior of 1,3-distearoyl-2-oleoyl-sn-glycerol (SOS) and trilaurin (LLL), as a typical model case of the mixture of cocoa butter (CB) and cocoa butter substitute (CBS). SOS was mixed with LLL at several mass fractions of LLL (wLLL); the mixtures obtained were analyzed for polymorphic phase behavior using differential scanning calorimetry (DSC) and synchrotron radiation X-ray diffractometry (SR-XRD). In melt crystallization with constant-rate cooling, SOS and LLL formed eutectics in their metastable polymorphs, allowing the occurrence of a compatible solid solution at wLLL ≥ 0.925. With subsequent heating, the resultant crystals transformed toward more stable polymorphs, then melted in a eutectic manner. For mixtures aged at 25 °C after melt crystallization, eutectics were found in the extended wLLL region, even at wLLL = 0.975. These results indicate that phase separation between SOS and LLL progressed in their solid solution under stabilization. The crystal growth of the separated SOS fraction may cause fat-bloom formation in compound chocolate containing CB and CBS. To solve this problem, the development of retardation techniques against phase separation is expected.
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75
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Singh K, Vaidyanathan S. Novel narrow band red emitters based on mixed metal oxides and their application in hybrid white light-emitting diodes. LUMINESCENCE 2020; 36:576-587. [PMID: 33140533 DOI: 10.1002/bio.3975] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2020] [Revised: 07/18/2020] [Accepted: 10/19/2020] [Indexed: 11/07/2022]
Abstract
A series of high-efficiency narrow band red-emitting La2 M2 O9 :Eu3+ (M = Mo/W) phosphors for white LEDs was synthesized using a conventional solid-state reaction method. All the compositions show absorption in the near ultraviolet (UV) light region due to charge transfer from O to M (M = W and Mo). In order to investigate the luminescence quenching effect, the Eu3+ concentration was varied in the La2 M2 O9 lattice. The tungstate analogue had a quantum yield of 46.5%, whereas the molybdate equivalent had a comparatively subordinate value (15.4%). The phosphor could be competently excited by ~395 or 465 nm photons (could be integrated well with a near-UV or blue LED chip) and showed dominant red emission electric-dipole transition (5 D0 →7 F2 ) with sharp spectral lines due to 4f-4f electronic transition of the Eu3+ ion and potential red-emitting colour converters for white LEDs. The red LED was fabricated by integrating the best phosphor composition with a near-UV LED and a white hybrid LED was fabricated by conjugating with a yellow organic dye and a red phosphor with near-UV LEDs. The white hybrid LED showed an excellent colour rendering index (83%), with CIE colour coordinates (0.313, 0.365) and CCT (6280 K).
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Affiliation(s)
- Kasturi Singh
- Department of Chemistry, National Institute of Technology, Rourkela, India
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76
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Yuan R, Xue D, Xue D, Li J, Ding X, Sun J, Lookman T. Knowledge-Based Descriptor for the Compositional Dependence of the Phase Transition in BaTiO 3-Based Ferroelectrics. ACS Appl Mater Interfaces 2020; 12:44970-44980. [PMID: 32924419 DOI: 10.1021/acsami.0c12763] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Descriptors play a central role in constructing composition-structure-property relationships to guide materials design. We propose a material descriptor, δτ, for the composition dependence of the Curie temperature (Tc) on single doping elements in BaTiO3 ferroelectrics, which is then generalized to a linear combination of multiple dopants in the solid solutions. The descriptor δτ depends linearly on the Curie temperature and also serves to separate the ferroelectric phase from the relaxor phase. We compare δτ to other commonly used descriptors such as the tolerance factor, electronegativity, and ionic displacement. By using regression analysis on our assembled experimental data, we show how it outperforms other descriptors. We use the trained machine-learned models to predict compositions in our search space with the largest ferroelectric, dielectric, and piezoelectric properties, namely, d33, electrostrain, and recoverable energy storage density. We experimentally verify our predictions for Tc and classification into ferroelectrics and relaxors by synthesizing and characterizing six solid solutions in BaTiO3 ferroelectrics. Our definition of δτ can shed light on the design of knowledge-based descriptors in other systems such as Pb-based and Bi-based solid solutions.
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Affiliation(s)
- Ruihao Yuan
- State Key Laboratory of Solidification Processing, Northwestern Polytechnical University, Xi'an 710072, China
- State Key Laboratory for Mechanical Behavior of Materials, Xi'an Jiaotong University, Xi'an 710049, China
- Theoretical Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, United States
| | - Deqing Xue
- School of Materials Science and Engineering, Xi'an University of Technology, Xi'an 710048, China
| | - Dezhen Xue
- State Key Laboratory for Mechanical Behavior of Materials, Xi'an Jiaotong University, Xi'an 710049, China
| | - Jinshan Li
- State Key Laboratory of Solidification Processing, Northwestern Polytechnical University, Xi'an 710072, China
| | - Xiangdong Ding
- State Key Laboratory for Mechanical Behavior of Materials, Xi'an Jiaotong University, Xi'an 710049, China
| | - Jun Sun
- State Key Laboratory for Mechanical Behavior of Materials, Xi'an Jiaotong University, Xi'an 710049, China
| | - Turab Lookman
- Theoretical Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, United States
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77
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Samolová E, Fábry J. Crystal structures of catena-poly[[μ-aqua-di-aqua(μ 3-2-methyl-propano-ato-κ 4 O: O, O': O')calcium] 2-methyl-propano-ate dihydrate], catena-poly[[μ-aqua-di-aqua-(μ 3-2-methyl-propano-ato-κ 4 O: O, O': O')strontium] 2-methyl-propano-ate dihydrate] and catena-poly[[μ-aqua-di-aqua-(μ 3-2-methyl-propano-ato-κ 4 O: O, O': O')(calcium/strontium)] 2-methyl-propano-ate dihydrate]. Acta Crystallogr E Crystallogr Commun 2020; 76:1684-1688. [PMID: 33117590 PMCID: PMC7534227 DOI: 10.1107/s2056989020012888] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/28/2020] [Accepted: 09/21/2020] [Indexed: 11/10/2022]
Abstract
The crystal structures of catena-poly[[μ-aqua-di-aqua-(μ3-2-methyl-propano-ato-κ4 O:O,O':O')calcium] 2-methyl-propano-ate dihydrate], {[Ca(C4H7O2)(H2O)3](C4H7O2)·2H2O} n , (I), catena-poly[[μ-aqua-di-aqua-(μ3-2-methyl-propano-ato-κ4 O:O,O':O')strontium] 2-methyl-propano-ate dihydrate], {[Sr(C4H7O2)(H2O)3](C4H7O2)·2H2O} n , (II), and catena-poly[[μ-aqua-di-aqua-(μ3-2-methyl-propano-ato-κ4 O:O,O':O')(calcium/strontium)] 2-methyl-propano-ate dihydrate], {[(Ca,Sr)(C4H7O2)(H2O)3](C4H7O2)·2H2O} n , (III), are related. (III) can be considered as an Sr-containing solid solution of (I), with Ca2+ and Sr2+ occupationally disordered in the ratio 0.7936 (16):0.2064 (16). (I)/(III) and (II) are homeotypic with different space groups of Pbca and Cmce, respectively. All the title crystal structures are composed of hydro-philic sheets containing the cations, carboxyl-ate groups as well as water mol-ecules. The hydro-phobic layers, which consist of 2-methyl-propano-ate chains, surround the hydro-philic sheets from both sides, thus forming a sandwich-like structure extending parallel to (001). The cohesion forces within these sheets are the cation-oxygen bonds and O-H⋯O hydrogen bonds of moderate strength. Stacking of these sandwiches along [001] is consolidated by van der Waals forces. The structures contain columns defined by the cation-oxygen inter-actions in which just one symmetry-independent 2-methyl-propano-ate anion is included, together with three water mol-ecules. These mol-ecules participate in an irregular coordination polyhedron composed of eight O atoms around the cation. Additional water mol-ecules as well as the second 2-methyl-propano-ate anion are not part of the coordination sphere. These mol-ecules are connected to the above-mentioned columns by O-H⋯O hydrogen bonds of moderate strength. In (II), the Sr2+ cation, two of the coordinating water mol-ecules and both anions are situated on a mirror plane with a concomitant positional disorder of the 2-methyl-propyl groups; the non-coordinating water mol-ecule also shows positional disorder of its hydrogen atom.
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Affiliation(s)
- Erika Samolová
- Inst. of Physics of the Czech Academy of Sciences, Na Slovance 2, 182 21 Praha 8, Czech Republic
| | - Jan Fábry
- Inst. of Physics of the Czech Academy of Sciences, Na Slovance 2, 182 21 Praha 8, Czech Republic
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78
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Umedov ST, Grigorieva AV, Lepnev LS, Knotko AV, Nakabayashi K, Ohkoshi SI, Shevelkov AV. Indium Doping of Lead-Free Perovskite Cs 2SnI 6. Front Chem 2020; 8:564. [PMID: 32850618 PMCID: PMC7417766 DOI: 10.3389/fchem.2020.00564] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2020] [Accepted: 06/02/2020] [Indexed: 12/02/2022] Open
Abstract
Structure and properties of an inorganic perovskite Cs2SnI6 demonstrated its potential as a light-harvester or electron-hole transport material; however, its optoelectronic properties are poorer than those of lead-based perovskites. Here, we report the way of light tuning of absorption and transport properties of cesium iodostannate(IV) Cs2SnI6 via partial heterovalent substitution of tin for indium. Light absorption and optical bandgaps of materials have been investigated by UV-vis absorption and photoluminescent spectroscopies. Low-temperature electron paramagnetic resonance spectroscopy was used to study the kind of paramagnetic centers in materials.
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Affiliation(s)
- Shodruz T Umedov
- Department of Materials Science, Lomonosov Moscow State University, Moscow, Russia
| | - Anastasia V Grigorieva
- Department of Materials Science, Lomonosov Moscow State University, Moscow, Russia.,Department of Chemistry, Lomonosov Moscow State University, Moscow, Russia
| | - Leonid S Lepnev
- Lebedev Physical Institute of the Russian Academy of Sciences, Moscow, Russia
| | - Alexander V Knotko
- Department of Materials Science, Lomonosov Moscow State University, Moscow, Russia.,Department of Chemistry, Lomonosov Moscow State University, Moscow, Russia
| | - Koji Nakabayashi
- Department of Chemistry, School of Sciences, University of Tokyo, Tokyo, Japan
| | - Shin-Ichi Ohkoshi
- Department of Chemistry, School of Sciences, University of Tokyo, Tokyo, Japan
| | - Andrei V Shevelkov
- Department of Chemistry, Lomonosov Moscow State University, Moscow, Russia
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79
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Beuchel A, Goddard R, Imming P, Seidel RW. A solid solution of ethyl and d 3-methyl 2-[(4-meth-yl-pyridin-2-yl)amino]-4-(pyridin-2-yl)thia-zole-5-carboxyl-ate. Acta Crystallogr E Crystallogr Commun 2020; 76:1255-1259. [PMID: 32844009 PMCID: PMC7405567 DOI: 10.1107/s2056989020008956] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2020] [Accepted: 07/01/2020] [Indexed: 11/11/2022]
Abstract
The synthesis of ethyl 2-[(4-methyl-pyridin-2-yl)amino)-4-(pyridin-2-yl)thia-zole- 5-carboxyl-ate via the Hantzsch reaction and partial in situ transesterification during recrystallization from methanol-d 4 to the d 3-methyl ester, resulting in the title solid solution, ethyl 2-[(4-methyl-pyridin-2-yl)amino)-4-(pyridin-2-yl)thia-zole-5-carboxyl-ate-d 3-methyl 2-[(4-methyl-pyridin-2-yl)amino)-4-(pyridin-2-yl)thia-zole-5-carboxyl-ate (0.88/0.12), 0.88C17H16N4O2S·0.12C16D3H11N4O2S, is reported. The refined ratio of ethyl to d 3-methyl ester in the crystal is 0.880 (6):0.120 (6). The pyridine ring is significantly twisted out of the plane of the approximately planar picoline thia-zole ester moiety. N-H⋯N hydrogen bonds between the secondary amino group and the pyridine nitro-gen atom of an adjacent symmetry-related mol-ecule link the mol-ecules into polymeric hydrogen-bonded zigzag tapes extending by glide symmetry in the [001] direction. There is structural evidence for intra-molecular N⋯S chalcogen bonding and inter-molecular weak C-H⋯O hydrogen bonds between adjacent zigzag tapes.
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Affiliation(s)
- Andreas Beuchel
- Institut für Pharmazie, Wolfgang-Langenbeck-Str. 4, 06120 Halle (Saale), Germany
| | - Richard Goddard
- Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm-Platz 1, 45470 Mülheim an der Ruhr, Germany
| | - Peter Imming
- Institut für Pharmazie, Wolfgang-Langenbeck-Str. 4, 06120 Halle (Saale), Germany
| | - Rüdiger W Seidel
- Institut für Pharmazie, Wolfgang-Langenbeck-Str. 4, 06120 Halle (Saale), Germany
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80
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Liang X, Shi L, Cao R, Wan G, Yan W, Chen H, Liu Y, Zou X. Perovskite-Type Solid Solution Nano-Electrocatalysts Enable Simultaneously Enhanced Activity and Stability for Oxygen Evolution. Adv Mater 2020; 32:e2001430. [PMID: 32686216 DOI: 10.1002/adma.202001430] [Citation(s) in RCA: 50] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/28/2020] [Revised: 06/27/2020] [Indexed: 06/11/2023]
Abstract
A trade-off between catalytic activity and structural stability generally exists in oxygen evolution electrocatalysis, especially in acidic environment. This dilemma limits the development of higher-performance electrocatalysts that are required by next-generation electrochemical technologies. Here it is demonstrated that the inverse catalytic activity-structural stability relation can be broken by alloying catalytically inert strontium zirconate with the other catalytically active perovskite, strontium iridate. This strategy results in an alloyed perovskite electrocatalyst with simultaneously improved iridium mass activity and structural stability, by about five times, for the oxygen evolution reaction under acidic conditions. The experimental and theoretical results suggest that the alloying strategy generates multiple positive effects, mainly including the reduction of catalyst size, the decrease of catalyst covalency, and the weakening of surface oxygen-binding ability. The synergistic optimization of bulk and surface properties, as a result, enhances the intrinsic activity and availability of surface iridium sites, whilst significantly inhibiting the surface cation corrosion during electrocatalysis.
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Affiliation(s)
- Xiao Liang
- State Key Laboratory of Inorganic Synthesis and Preparative Chemistry, College of Chemistry, Jilin University, Changchun, 130012, P. R. China
| | - Lei Shi
- State Key Laboratory of Inorganic Synthesis and Preparative Chemistry, College of Chemistry, Jilin University, Changchun, 130012, P. R. China
| | - Rui Cao
- Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, Stanford University, Menlo Park, CA, 94025, USA
| | - Gang Wan
- Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, Stanford University, Menlo Park, CA, 94025, USA
| | - Wensheng Yan
- National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei, Anhui, 230029, P. R. China
| | - Hui Chen
- State Key Laboratory of Inorganic Synthesis and Preparative Chemistry, College of Chemistry, Jilin University, Changchun, 130012, P. R. China
| | - Yipu Liu
- State Key Laboratory of Inorganic Synthesis and Preparative Chemistry, College of Chemistry, Jilin University, Changchun, 130012, P. R. China
- School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore, 637371, Singapore
| | - Xiaoxin Zou
- State Key Laboratory of Inorganic Synthesis and Preparative Chemistry, College of Chemistry, Jilin University, Changchun, 130012, P. R. China
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81
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Tan Z, Chu Y, Chen J, Li J, Ji G, Niu G, Gao L, Xiao Z, Tang J. Lead-Free Perovskite Variant Solid Solutions Cs 2 Sn 1- x Te x Cl 6 : Bright Luminescence and High Anti-Water Stability. Adv Mater 2020; 32:e2002443. [PMID: 32596962 DOI: 10.1002/adma.202002443] [Citation(s) in RCA: 57] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/09/2020] [Revised: 05/14/2020] [Indexed: 06/11/2023]
Abstract
Underwater lighting is important for the exploration of the underwater world in different areas. It is of great significance for developing underwater emitters with high penetrability, high luminous efficiency, good anti-water stability, and environmental friendliness. Stable lead-free perovskite luminescent materials, represented by vacancy-ordered double perovskites, are worthy of research because they can almost meet the above requirements. Here, lead-free perovskite variant solid solutions with the formula of Cs2 Sn1- x Tex Cl6 are reported. Upon the exchange of Sn/Te ions, strong Jahn-Teller distortion of octahedra occurs in the lattice structure. The combination of Te luminescent center and Jahn-Teller-like self-trapped excitons gives this material yellow-green luminescence with a wavelength of 580 nm and a high photoluminescence quantum yield of 95.4%. Moreover, these solid solutions can withstand the extreme conditions of immersion in water probably due to the formation of amorphous alteration phase. Such good anti-water stability is also supported by the molecule dynamics simulation result that no reaction occurs on the water/Cs2 SnCl6 interface. The high luminous, suitable wavelength, and good anti-water stability enable the solid solutions suitable for the application for underwater lighting.
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Affiliation(s)
- Zhifang Tan
- Wuhan National Laboratory for Optoelectronics, Huazhong University of Science and Technology, Wuhan, 430074, China
- School of Optical and Electronic Information, Huazhong University of Science and Technology, Wuhan, 430074, China
| | - Yanmeng Chu
- Wuhan National Laboratory for Optoelectronics, Huazhong University of Science and Technology, Wuhan, 430074, China
| | - Jinxi Chen
- Wuhan National Laboratory for Optoelectronics, Huazhong University of Science and Technology, Wuhan, 430074, China
- School of Optical and Electronic Information, Huazhong University of Science and Technology, Wuhan, 430074, China
| | - Jinghui Li
- Wuhan National Laboratory for Optoelectronics, Huazhong University of Science and Technology, Wuhan, 430074, China
| | - Guoqi Ji
- Wuhan National Laboratory for Optoelectronics, Huazhong University of Science and Technology, Wuhan, 430074, China
| | - Guangda Niu
- Wuhan National Laboratory for Optoelectronics, Huazhong University of Science and Technology, Wuhan, 430074, China
| | - Liang Gao
- Wuhan National Laboratory for Optoelectronics, Huazhong University of Science and Technology, Wuhan, 430074, China
| | - Zewen Xiao
- Wuhan National Laboratory for Optoelectronics, Huazhong University of Science and Technology, Wuhan, 430074, China
| | - Jiang Tang
- Wuhan National Laboratory for Optoelectronics, Huazhong University of Science and Technology, Wuhan, 430074, China
- School of Optical and Electronic Information, Huazhong University of Science and Technology, Wuhan, 430074, China
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82
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Luo C, Yang T, Huang Q, Liu X, Ling H, Zhu Y, Xia G, Zou W, Wang H. CuMo xW (1-x)O 4 Solid Solution Display Visible Light Photoreduction of CO 2 to CH 3OH Coupling with Oxidation of Amine to Imine. Nanomaterials (Basel) 2020; 10:E1303. [PMID: 32635203 DOI: 10.3390/nano10071303] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/16/2020] [Revised: 06/24/2020] [Accepted: 06/28/2020] [Indexed: 11/17/2022]
Abstract
The photoreduction of carbon dioxide (CO2) to valuable fuels is a promising strategy for the prevention of rising atmospheric levels of CO2 and the depletion of fossil fuel reserves. However, most reported photocatalysts are only active in the ultraviolet region, which necessitates co-catalysts and sacrificial agents in the reaction systems, leading to an unsatisfied economy of the process in energy and atoms. In this research, a CuMoxW(1-x)O4 solid solution was synthesized, characterized, and tested for the photocatalytic reduction of CO2 in the presence of amines. The results revealed that the yield of CH3OH from CO2 was 1017.7 μmol/g under 24 h visible light irradiation using CuW0.7Mo0.3O4 (x = 0.7) as the catalyst. This was associated with the maximum conversion (82.1%) of benzylamine to N-benzylidene benzylamine with high selectivity (>99%). These results give new insight into the photocatalytic reduction of CO2 for valuable chemical products in an economic way.
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83
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Kuz’micheva G, Kaurova I. Peculiar Structural Effects in Pure and Doped Functional Single Crystals of Complex Compositions. Molecules 2020; 25:molecules25102451. [PMID: 32466174 PMCID: PMC7287726 DOI: 10.3390/molecules25102451] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2020] [Revised: 05/18/2020] [Accepted: 05/19/2020] [Indexed: 11/16/2022] Open
Abstract
Results of a detailed structural characterization of nominally pure and doped single crystals of scheelite, eulytin, and perovskite families obtained by melt methods were considered and analyzed. The influence of growth and post-growth annealing conditions on actual compositions of crystals is shown. The reasons for the coloration of the crystals are explained. A change in crystal symmetry due to crystal–chemical and growth reasons is considered. The use of structural analysis and X-ray absorption spectroscopy is substantiated to reveal the role of activator ions in the formation of statistical and local structures, respectively. A relationship between the distribution of activator ions over crystallographic sites and photoluminescent parameters of materials is established, which allows selecting optimal systems for the application. The combined results of studying single-crystal compounds of other classes (huntite, sillenite, whitlockite, garnet, tetragonal bronzes) allow formulating and summarizing structural effects that appeared in the systems and caused by various factors and, in many cases, due to the local environment of cations. A principal difference in the structural behavior of solid solutions and doped compounds is shown. The methodology developed for single-crystal samples of complex compositions can be recommended for the systematic structural studies of functional materials of different compositions.
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Du H, An H, Zhang J, Ding Y, Lian C, Bai H. A Novel Optimization Model and Application of Optimal Formula Design for Cu xCo 1-xFe 2O 4 Spinel-Based Coating Slurry in Relation to Near and Middle Infrared Radiation Strengthening. Materials (Basel) 2020; 13:ma13102332. [PMID: 32438669 PMCID: PMC7287822 DOI: 10.3390/ma13102332] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/06/2020] [Revised: 05/14/2020] [Accepted: 05/18/2020] [Indexed: 06/11/2023]
Abstract
Coating slurry, in which the infrared radiation material is the main content, is applied in industrial furnaces to improve heat transfer and raise efficiency of furnaces. In this study, a CuxCo1-xFe2O4 series material with a spinel structure was prepared, and the emissivity of different formulas in two wavebands (3-5 μm and 8-14 μm) was measured. To ensure that the material delivered high emissivity, optimization models were proposed using Matlab software, and proportions of CuO, Co2O3 and Fe2O3 were found to be 16.98%, 16.73% and 66.29%, respectively, in the optimal formula. Thus, using the CuxCo1-xFe2O4 series material and additives, according to mixture regression method, fifteen formulas of coating slurry were designed, prepared and the emissivities were measured. With the Matlab software optimization model, the content of coating slurry was optimized and the corresponding emissivities were measured to be 0.931 and 0.905 in two wavebands, which is in agreement with the optimized calculation.
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Affiliation(s)
- Haiqing Du
- Department of Mechanical Engineering, Zhejiang Industry Polytechnic College, Shaoxing 312000, China
| | - Haifei An
- State Key Laboratory of Advanced Metallurgy, University of Science and Technology Beijing, Beijing 100083, China; (H.A.); (J.Z.); (Y.D.); (C.L.); (H.B.)
- School of Metallurgical and Ecological Engineering, University of Science and Technology Beijing, Beijing 100083, China
| | - Jian Zhang
- State Key Laboratory of Advanced Metallurgy, University of Science and Technology Beijing, Beijing 100083, China; (H.A.); (J.Z.); (Y.D.); (C.L.); (H.B.)
- School of Metallurgical and Ecological Engineering, University of Science and Technology Beijing, Beijing 100083, China
| | - Yuhao Ding
- State Key Laboratory of Advanced Metallurgy, University of Science and Technology Beijing, Beijing 100083, China; (H.A.); (J.Z.); (Y.D.); (C.L.); (H.B.)
- School of Metallurgical and Ecological Engineering, University of Science and Technology Beijing, Beijing 100083, China
| | - Chao Lian
- State Key Laboratory of Advanced Metallurgy, University of Science and Technology Beijing, Beijing 100083, China; (H.A.); (J.Z.); (Y.D.); (C.L.); (H.B.)
- School of Metallurgical and Ecological Engineering, University of Science and Technology Beijing, Beijing 100083, China
| | - Hao Bai
- State Key Laboratory of Advanced Metallurgy, University of Science and Technology Beijing, Beijing 100083, China; (H.A.); (J.Z.); (Y.D.); (C.L.); (H.B.)
- School of Metallurgical and Ecological Engineering, University of Science and Technology Beijing, Beijing 100083, China
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85
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Wei Z, Wang C, Zhang J, Yang J, Li Z, Zhang Q, Luo P, Zhang W, Liu E, Luo J. Precise Regulation of Carrier Concentration in Thermoelectric BiSbTe Alloys via Magnetic Doping. ACS Appl Mater Interfaces 2020; 12:20653-20663. [PMID: 32286043 DOI: 10.1021/acsami.0c02408] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
The Bi2Te3-based alloy is the best commercial thermoelectric material around room temperature, although it is extremely difficult to further improve its thermoelectric performance. In this work, we demonstrate that magnetic doping is an effective strategy to regulate the thermoelectric performance of p-type Bi0.5Sb1.5Te3. According to our experiments, it is much more difficult for ferromagnetic Fe/Co to enter the Bi0.5Sb1.5Te3 lattice in comparison with diamagnetic Pb, which can be understood by the "like dissolves like" rule. At the same doping content, Fe and Co provide much lower hole carriers than Pb due to their larger carrier thermal activation energies, indicating that Fe and Co as dopants are very applicable for the fine regulation of the carrier concentration. The Fe/Co-doped samples have higher Seebeck coefficients but less carrier mobilities than the Pb-doped sample since the doped magnetic atoms induce additional carrier scattering. Beyond the solid solubility limit, excess Fe/Co represents as the impurity, which can maintain a high carrier concentration due to the metal-semiconductor contact. Finally, the zT values of ∼1.05 and 1.15 near room temperature have been achieved for the samples with 1.71 at. % Co and 1.80 at. % Fe, respectively.
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Affiliation(s)
- Zichen Wei
- School of Materials Science and Engineering, Shanghai University, 99 Shangda Road, Shanghai 200444, China
| | - Chenyang Wang
- School of Materials Science and Engineering, Shanghai University, 99 Shangda Road, Shanghai 200444, China
| | - Jiye Zhang
- School of Materials Science and Engineering, Shanghai University, 99 Shangda Road, Shanghai 200444, China
| | - Jiong Yang
- Materials Genome Institute, Shanghai University, 99 Shangda Road, Shanghai 200444, China
| | - Zhili Li
- School of Materials Science and Engineering, Shanghai University, 99 Shangda Road, Shanghai 200444, China
| | - Qidong Zhang
- School of Materials Science and Engineering, Shanghai University, 99 Shangda Road, Shanghai 200444, China
| | - Pengfei Luo
- School of Materials Science and Engineering, Shanghai University, 99 Shangda Road, Shanghai 200444, China
| | - Wenqing Zhang
- State Key Laboratory for Magnetism, Institute of Physics Chinese Academy of Sciences, P. O. Box 603, Beijing 100190, China
| | - Enke Liu
- Institute for Quantum Science and Engineering, Department of Physics, Southern University of Science and Technology, 1088 Xueyuan Avenue, Shenzhen 518055, China
| | - Jun Luo
- School of Materials Science and Engineering, Shanghai University, 99 Shangda Road, Shanghai 200444, China
- Materials Genome Institute, Shanghai University, 99 Shangda Road, Shanghai 200444, China
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86
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Xu J, Jiang S, Du Y. Unravelling the Mystery of Solid Solutions: A Case Study of 89 Y Solid-State NMR Spectroscopy. Chemphyschem 2020; 21:825-836. [PMID: 32100919 DOI: 10.1002/cphc.202000148] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2020] [Revised: 02/25/2020] [Indexed: 11/10/2022]
Abstract
Incorporating heteroatoms in functional materials is an invaluable approach to modulate their properties, assuming a solid solution is formed. However, thorough understanding of key structural information on the resulting solid solution, such as the local environment of cations and vacancies, remains a challenge. Solid-state NMR (SSNMR) spectroscopy is a powerful structural characterization tool, very sensitive to the local environment. Due to the difficulty in signal acquisition and spectral interpretation, SSNMR spectroscopy is relatively less known to chemists and materials scientists. Herein, we present an introductory review to demonstrate how to use 89 Y SS NMR spectroscopy to unravel the mystery of solid solutions. In general, 89 Y chemical shift varies with different cation/vacancy arrangements in Y coordination spheres, providing ultrafine structural information in the atomic scale. As a case study and an extreme condition, the approach demonstrated in this review can be extended to other systems.
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Affiliation(s)
- Jun Xu
- Center for Rare Earth and Inorganic Functional Materials, Tianjin Key Lab for Rare Earth Materials and Applications, School of Materials Science and Engineering & National Institute for Advanced Materials, Nankai University, Tianjin, 300350, P.R. China
| | - Shijia Jiang
- Center for Rare Earth and Inorganic Functional Materials, Tianjin Key Lab for Rare Earth Materials and Applications, School of Materials Science and Engineering & National Institute for Advanced Materials, Nankai University, Tianjin, 300350, P.R. China
| | - Yaping Du
- Center for Rare Earth and Inorganic Functional Materials, Tianjin Key Lab for Rare Earth Materials and Applications, School of Materials Science and Engineering & National Institute for Advanced Materials, Nankai University, Tianjin, 300350, P.R. China
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87
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Gstir T, Kahlenberg V, Krüger H, Penner S. Synthesis and crystal structure of ABW-type SrFe 1.40V 0.60O 4. Acta Crystallogr E Crystallogr Commun 2020; 76:664-667. [PMID: 32431929 PMCID: PMC7199274 DOI: 10.1107/s205698902000496x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2020] [Accepted: 04/08/2020] [Indexed: 11/14/2023]
Abstract
Single crystals of SrFe1.40V0.60O4, strontium tetra-oxidodi[ferrate(III)/vanad-ate(III)], have been obtained as a side product in the course of sinter experiments aimed at the synthesis of double perovskites in the system SrO-Fe2O3-V2O5. The crystal structure can be characterized by layers of six-membered rings of TO4-tetra-hedra (T: FeIII, VIII) perpendicular to [100]. Stacking of the layers along [100] results in a three-dimensional framework enclosing tunnel-like cavities in which SrII cations are incorporated for charge compensation. The sequence of directedness of up (U) and down (D) pointing vertices of neighboring tetra-hedra in a single six-membered ring is UUUDDD. The topology of the tetra-hedral framework belongs to the zeolite-type ABW.
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Affiliation(s)
- Thomas Gstir
- University of Innsbruck, Institute of Mineralogy & Petrography, Innrain 52, A-6020 Innsbruck, Austria
| | - Volker Kahlenberg
- University of Innsbruck, Institute of Mineralogy & Petrography, Innrain 52, A-6020 Innsbruck, Austria
| | - Hannes Krüger
- University of Innsbruck, Institute of Mineralogy & Petrography, Innrain 52, A-6020 Innsbruck, Austria
| | - Simon Penner
- University of Innsbruck, Department of Physical Chemistry, Innrain 52c, A-6020 Innsbruck, Austria
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88
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Hunter HA, Ling FT, Peters CA. Metals Coprecipitation with Barite: Nano-XRF Observation of Enhanced Strontium Incorporation. Environ Eng Sci 2020; 37:235-245. [PMID: 32322155 PMCID: PMC7175618 DOI: 10.1089/ees.2019.0447] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/11/2019] [Accepted: 01/03/2020] [Indexed: 05/23/2023]
Abstract
Coprecipitation can be an effective treatment method for the removal of environmentally relevant metals from industrial wastewaters such as produced waters from the oil and gas industry. The precipitation of barite, BaSO4, through the addition of sulfate removes barium while coprecipitating strontium and other alkaline earth metals even when these are present at concentrations below their solubility limit. Among other analytical methods, X-ray fluorescence (XRF) nanospectroscopy at the Hard X-ray Nanoprobe (HXN) beamline at the National Synchrotron Light Source II (NSLS-II) was used to quantify Sr incorporation into barite. Thermodynamic modeling of (Ba,Sr)SO4 solid solutions was done using solid solution-aqueous solution (SS-AS) theory. The quantitative, high-resolution nano-XRF data show clearly that the Sr content in (Ba,Sr)SO4 solid solutions varies widely among particles and even within a single particle. We observed substantial Sr incorporation that is far larger than thermodynamic models predict, likely indicating the formation of metastable solid solutions. We also observed that increasing barite supersaturation of the aqueous phase led to increased Sr incorporation, as predicted by available kinetic models. These results suggest that coprecipitation offers significant potential for designing treatment systems for aqueous metals' removal in desired metastable compositions. Solution conditions may be optimized to enhance the incorporation of Sr by increasing sulfate addition such that the barite saturation index remains above ∼3 or by increasing the aqueous Sr to Ba ratio.
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Affiliation(s)
- Heather A. Hunter
- Department of Civil & Environmental Engineering, Princeton University, Princeton, New Jersey
| | - Florence T. Ling
- Department of Civil & Environmental Engineering, Princeton University, Princeton, New Jersey
| | - Catherine A. Peters
- Department of Civil & Environmental Engineering, Princeton University, Princeton, New Jersey
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89
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Liu J, Feng J, Lu L, Wu B, Ren P, Shi W, Cheng P. A Metal-Organic-Framework-Derived (Zn 0.95Cu 0.05) 0.6Cd 0.4S Solid Solution as Efficient Photocatalyst for Hydrogen Evolution Reaction. ACS Appl Mater Interfaces 2020; 12:10261-10267. [PMID: 32023414 DOI: 10.1021/acsami.9b19257] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Photocatalytic water splitting taking the advantage of using solar energy directly is one of the most effective strategies for hydrogen evolution. The development of facile methods for synthesizing highly efficient and stable photocatalysts for hydrogen production still remains a great challenge. Herein, a metal-organic framework (MOF)-templated strategy was designed for the synthesis of solid solutions of (Zn0.95Cu0.05)1-xCdxS that exhibit outstanding photocatalytic hydrogen production reaction activity. More importantly, efficient light capturing ability and photogenerated charges separation were accomplished via fine-tuning the composition of the photocatalysts by adjusting the concentrations of doping metals in the template MOFs. Under visible light (λ > 420 nm), an optimized nanocatalyst, (Zn0.95Cu0.05)0.6Cd0.4S, exhibited a higher durability and satisfied photocatalytic hydrogen evolution rate of 4150.1 μmol g-1 h-1 of water splitting.
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Affiliation(s)
- Jing Liu
- Key Laboratory of Advanced Energy Materials Chemistry (MOE), College of Chemistry, Nankai University, Tianjin 300071, China
| | - Jianrui Feng
- Key Laboratory of Advanced Energy Materials Chemistry (MOE), College of Chemistry, Nankai University, Tianjin 300071, China
| | - Lele Lu
- Key Laboratory of Advanced Energy Materials Chemistry (MOE), College of Chemistry, Nankai University, Tianjin 300071, China
| | - Boyuan Wu
- Key Laboratory of Advanced Energy Materials Chemistry (MOE), College of Chemistry, Nankai University, Tianjin 300071, China
| | - Peng Ren
- School of Science, Harbin Institute of Technology (Shenzhen), Shenzhen 518055, China
| | - Wei Shi
- Key Laboratory of Advanced Energy Materials Chemistry (MOE), College of Chemistry, Nankai University, Tianjin 300071, China
| | - Peng Cheng
- Key Laboratory of Advanced Energy Materials Chemistry (MOE), College of Chemistry, Nankai University, Tianjin 300071, China
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90
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Lou Z, Wang Y, Yang Y, Wang Y, Qin C, Liang R, Chen X, Ye Z, Zhu L. Carbon Sphere Template Derived Hollow Nanostructure for Photocatalysis and Gas Sensing. Nanomaterials (Basel) 2020; 10:nano10020378. [PMID: 32098174 PMCID: PMC7075306 DOI: 10.3390/nano10020378] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/12/2020] [Revised: 02/17/2020] [Accepted: 02/17/2020] [Indexed: 12/11/2022]
Abstract
As a green and preferred technology for energy crisis and environmental issues, continuous research on photocatalysis and gas sensing has come forth at an explosive rate. Thus far, promising synthetic methods have enabled various designs and preparations of semiconductor-based nanostructure which have shown superior activity. This review summarized various synthetic routines toward carbon sphere template derived hollow nanostructures and their successful attempts in synthesize doping, solid solution, heterostructure, and surface modified nanostructures for heterogeneous photocatalysis and gas sensing. Moreover, the challenges and future prospects are briefly discussed. It is eagerly anticipated that this review may broaden the view and in-depth understanding of carbon sphere template derived hollow nanostructures while expected to have further progresses in heterogeneous photocatalysis, gas sensing and other related fields which will make great contributions to their application.
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91
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Li J, Yang W, Wu A, Zhang X, Xu T, Liu B. Band-Gap Tunable 2D Hexagonal (GaN) 1-x(ZnO) x Solid-Solution Nanosheets for Photocatalytic Water Splitting. ACS Appl Mater Interfaces 2020; 12:8583-8591. [PMID: 31945289 DOI: 10.1021/acsami.9b21793] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
A (GaN)1-x(ZnO)x solid solution as a promising visible-light-driven photocatalyst for overall water splitting has attracted extensive attention. In this work, we proposed a template reactive strategy toward the synthesis of band-gap tunable 2D (GaN)1-x(ZnO)x nanosheets as thin as 14 nm to reduce the carrier transportation path and thus efficiently decrease the recombination of electrons and holes. It is demonstrated that the template strategy enables an ideal morphology and structure transformation from hexagonal 2D ZnGa2O4 nanosheets to 2D (GaN)1-x(ZnO)x nanosheets in the nitridation process. After the modification of 1 wt % of Rh cocatalyst, the flowerlike (GaN)0.89(ZnO)0.11 nanosheets show an enhanced hydrogen evolution in pure water (pH 4.5).
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Affiliation(s)
- Jing Li
- Shenyang National Laboratory for Materials Science (SYNL) , Institute of Metal Research (IMR), Chinese Academy of Sciences (CAS) , No. 72 Wenhua Road , Shenyang 110016 , China
| | - Wenjin Yang
- Shenyang National Laboratory for Materials Science (SYNL) , Institute of Metal Research (IMR), Chinese Academy of Sciences (CAS) , No. 72 Wenhua Road , Shenyang 110016 , China
| | - Aimin Wu
- Key Laboratory of Materials Modification by Laser, Ion, and Electron Beams (Ministry of Education) , Dalian University of Technology , Dalian 116024 , China
| | - Xinglai Zhang
- Shenyang National Laboratory for Materials Science (SYNL) , Institute of Metal Research (IMR), Chinese Academy of Sciences (CAS) , No. 72 Wenhua Road , Shenyang 110016 , China
| | - Tingting Xu
- Shenyang National Laboratory for Materials Science (SYNL) , Institute of Metal Research (IMR), Chinese Academy of Sciences (CAS) , No. 72 Wenhua Road , Shenyang 110016 , China
| | - Baodan Liu
- Shenyang National Laboratory for Materials Science (SYNL) , Institute of Metal Research (IMR), Chinese Academy of Sciences (CAS) , No. 72 Wenhua Road , Shenyang 110016 , China
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92
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Abstract
Group 2, 3, and 13 element-doped zirconium oxide catalysts M-ZrO2 (M = Mg, Sr, Y, La, Ce, Sm, Er, Yb, B, Al, Ga, In, and Tl; 5 mol%) were prepared by impregnation of each metal salt aqueous solution on amorphous zirconium hydroxide, followed by calcination at 773 K. The M-ZrO2 samples were characterized by the catalytic performance of 2-butanol decomposition at 573 K, XRD, XANES and EXAFS spectroscopic techniques. Detailed analyses were performed herein for a series of Ga-ZrO2 with various doping amounts in the range of 1 - 60 mol%. The addition of Group 2 and 3 elements little influenced the catalytic performance of ZrO2 itself to promote dehydration to produce 1-butene with 90% selectivity. Ga-ZrO2 and In-ZrO2 gave methyl ethyl ketone as the main product via dehydrogenation. The doped Ga ion mainly existed inside the bulk of zirconia by forming the GaxZr1-xO2 solid solution up to 5 mol%. Highly doped species more than 10 mol% aggregated to form ε-Ga2O3. Each fraction forming the solid solution and Ga2O3-like species was evaluated by XANES analysis.
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Affiliation(s)
- Takashi Yamamoto
- Department of Natural Science, Faculty of Science and Technology, Tokushima University.,Department of Mathematical and Material Sciences, Faculty of Integrated Arts and Sciences, Tokushima University
| | - Akihito Kurimoto
- Department of Mathematical and Material Sciences, Faculty of Integrated Arts and Sciences, Tokushima University
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93
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Xu Z, Utton C, Tsakiropoulos P. A Study of the Effect of 5 at.% Sn on the Micro-Structure and Isothermal Oxidation at 800 and 1200 °C of Nb-24Ti-18Si Based Alloys with Al and/or Cr Additions. Materials (Basel) 2020; 13:E245. [PMID: 31935906 PMCID: PMC6981790 DOI: 10.3390/ma13010245] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/21/2019] [Revised: 12/19/2019] [Accepted: 12/24/2019] [Indexed: 11/16/2022]
Abstract
This paper presents the results of a systematic study of Nb-24Ti-18Si based alloys with 5 at.% Sn addition. Three alloys of nominal compositions (at.%), namely Nb-24Ti-18Si-5Cr-5Sn (ZX4), Nb-24Ti-18Si-5Al-5Sn (ZX6), and Nb-24Ti-18Si-5Al-5Cr-5Sn (ZX8), were studied to understand how the increased Sn concentration improved oxidation resistance. In all three alloys there was macrosegregation, which was most severe in ZX8 and the primary βNb5Si3 transformed completely to αNb5Si3 after heat treatment. The Nbss was not stable in ZX6, the Nb3Sn was stable in all three alloys, and the Nbss and C14-NbCr2 Laves phase were stable in ZX4 and ZX8. The 5 at.% Sn addition suppressed pest oxidation at 800 °C but not scale spallation at 1200 °C. At both temperatures, a Sn-rich area with Nb3Sn, Nb5Sn2Si, and NbSn2 compounds developed below the scale. This area was thicker and continuous after oxidation at 1200 °C and was contaminated by oxygen at both temperatures. The contamination of the Nbss by oxygen was most severe in the bulk of all three alloys. Nb-rich, Ti-rich and Nb and Si-rich oxides formed in the scales. The adhesion of the latter on ZX6 at 1200 °C was better, compared with the alloys ZX4 and ZX8. At both temperatures, the improved oxidation was accompanied by a decrease and increase respectively of the alloy parameters VEC (Valence Electron Concentration) and δ, in agreement with the alloy design methodology NICE (Niobium Intermetallic Composite Elaboration). Comparison with similar alloys with 2 at.% Sn addition showed (a) that a higher Sn concentration is essential for the suppression of pest oxidation of Nb-24Ti-18Si based alloys with Cr and no Al additions, but not for alloys where Al and Cr are in synergy with Sn, (b) that the stability of Nb3Sn in the alloy is "assured" with 5 at.% Sn addition, which improves oxidation with/out the presence of the Laves phase and (c) that the synergy of Sn with Al presents the "best" oxidation behaviour with improved scale adhesion at high temperature.
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Affiliation(s)
| | | | - Panos Tsakiropoulos
- Department of Materials Science and Engineering, Sir Robert Hadfield Building, The University of Sheffield, Mappin Street, Sheffield S1 3JD, UK; (Z.X.); (C.U.)
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94
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Heo TW, Wood BC. On Thermodynamic and Kinetic Mechanisms for Stabilizing Surface Solid Solutions. ACS Appl Mater Interfaces 2019; 11:48487-48496. [PMID: 31766847 DOI: 10.1021/acsami.9b14104] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Many processes for energy storage rely on transformations between phases with strong separation tendencies. In these systems, performance limitations can arise from undesirable chemical and mechanical factors associated with the phase separation behavior. Solid solutions represent a desirable alternative, provided the conditions for their formation are known. Here, we invoke linear stability theory and diffuse-interface mesoscopic simulations to demonstrate that solid solutions can be stabilized near surface layers of phase-separating systems. Two factors are found to drive surface solid-solution formation: surface relaxation of solution self-strain energy and anisotropy of diffusion mobility. Using a strongly phase-separating LiXFePO4 particle as a model system, we show that the relaxation of the solution self-strain energy competes against the relaxation of the coherency strain energy to stabilize surface solid solutions. Our theoretical understanding also suggests that highly anisotropic diffusion mobility can provide an alternative kinetic route to achieve the same aim, with stabilizing behavior strongly dependent on the specific alignment of the surface orientation. Our findings provide fundamental guidance for manipulating solid-solution behavior in nanoscale structures, in which surface effects become especially significant. Beyond energy storage materials, our findings have important implications for understanding solid-solution formation in other phase-separating systems from metal alloys to ceramics.
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Affiliation(s)
- Tae Wook Heo
- Materials Science Division , Lawrence Livermore National Laboratory , Livermore , California 94550 , United States
| | - Brandon C Wood
- Materials Science Division , Lawrence Livermore National Laboratory , Livermore , California 94550 , United States
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95
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Wang Q, Chen H, Wang F. Effect of Trace Zn Addition on Interfacial Evolution in Sn-10Bi/Cu Solder Joints during Aging Condition. Materials (Basel) 2019; 12:E4240. [PMID: 31861193 DOI: 10.3390/ma12244240] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/21/2019] [Revised: 11/26/2019] [Accepted: 12/16/2019] [Indexed: 11/27/2022]
Abstract
Excessive growth of intermetallic compounds (IMCs) during service affects the reliability of solder joints, so how to suppress the growth of IMC thickness at the interface in solder joints becomes a widespread concern. In this work, the interfacial reaction between Sn-10Bi solder and Cu substrate after thermal aging was investigated. Moreover, to depress the IMC growth at the interface, trace amounts of Zn was added into the Sn-10Bi solder, and the interfacial reactions of Sn-10Bi-xZn solders (x = 0.2, 0.5) and Cu substrate after thermal aging were studied in this paper. Compounds such as Cu6(Sn, Zn)5 and Cu5Zn8 were formed at the interface after adding trace amounts of Zn. The addition of 0.2 and 0.5 wt% Zn significantly inhibited the thickness growth of IMCs and the formation of Cu3Sn IMC at the interface of Sn-10Bi-0.2Zn/Cu and Sn-10Bi-0.5Zn/Cu during thermal aging. Therefore, the addition of trace Zn had an obvious effect on the interfacial reaction of Sn-10Bi/Cu solder joint. Interestingly, the evolution of IMC thickness in Sn-10Bi-0.5Zn/Cu solder joints was completely different from that in Sn-10Bi or Sn-10Bi-0.2Zn solder joints, in which the spalling of IMCs occurred. In order to explore the mechanisms on the depressing effect from the addition of trace Zn, the activation energy Q in solder joints during aging was calculated.
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96
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Zhao L, Kang Q, Guan X, Martyniuk CJ. Hydrotalcite-based CeNiAl mixed oxides for SO 2 adsorption and oxidation. Environ Technol 2019; 40:3678-3688. [PMID: 29869948 DOI: 10.1080/09593330.2018.1485749] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/27/2017] [Accepted: 06/04/2018] [Indexed: 06/08/2023]
Abstract
The impact of Ce on SO2 adsoption and oxidation was studied over a series of flower-like hydrotalcite-based CeNiAl mixed oxides. Combined with XRD, BET, pyridine chemisorption, CO2-TPD, XPS and H2-TPR results, it revealed that introduction of Ce into NiAlO generates new centres for oxygen storage and release, promotes the enhancement of Lewis acid strength, increases weakly and strongly alkaline sites, and increases ability for SO2 adsorption and oxidation. Furthermore, in situ Fourier transform infrared spectroscopy revealed that adsorbed SO2 molecules formed surface bidentate binuclear sulfate. Taken together, we propose that the addition of Ce4+ to NiAlO acts to improve this compound as major adsorbent for SO2.
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Affiliation(s)
- Ling Zhao
- School of Ecology and Environment, Inner Mongolia University, Hohhot, People's Republic of China
- Center for Environmental and Human Toxicology, Department of Physiological Sciences, College of Veterinary Medicine, University of Florida, Gainesville, FL, USA
| | - Qi Kang
- School of Ecology and Environment, Inner Mongolia University, Hohhot, People's Republic of China
| | - Xiongfei Guan
- School of Ecology and Environment, Inner Mongolia University, Hohhot, People's Republic of China
| | - Christopher J Martyniuk
- Center for Environmental and Human Toxicology, Department of Physiological Sciences, College of Veterinary Medicine, University of Florida, Gainesville, FL, USA
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Cho JY, Siyar M, Jin WC, Hwang E, Bae SH, Hong SH, Kim M, Park C. Electrical Transport and Thermoelectric Properties of SnSe-SnTe Solid Solution. Materials (Basel) 2019; 12:ma12233854. [PMID: 31766632 PMCID: PMC6926679 DOI: 10.3390/ma12233854] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/28/2019] [Revised: 11/14/2019] [Accepted: 11/19/2019] [Indexed: 12/22/2022]
Abstract
SnSe is considered as a promising thermoelectric (TE) material since the discovery of the record figure of merit (ZT) of 2.6 at 926 K in single crystal SnSe. It is, however, difficult to use single crystal SnSe for practical applications due to the poor mechanical properties and the difficulty and cost of fabricating a single crystal. It is highly desirable to improve the properties of polycrystalline SnSe whose TE properties are still not near to that of single crystal SnSe. In this study, in order to control the TE properties of polycrystalline SnSe, polycrystalline SnSe–SnTe solid solutions were fabricated, and the effect of the solid solution on the electrical transport and TE properties was investigated. The SnSe1−xTex samples were fabricated using mechanical alloying and spark plasma sintering. X-ray diffraction (XRD) analyses revealed that the solubility limit of Te in SnSe1−xTex is somewhere between x = 0.3 and 0.5. With increasing Te content, the electrical conductivity was increased due to the increase of carrier concentration, while the lattice thermal conductivity was suppressed by the increased amount of phonon scattering. The change of carrier concentration and electrical conductivity is explained using the measured band gap energy and the calculated band structure. The change of thermal conductivity is explained using the change of lattice thermal conductivity from the increased amount of phonon scattering at the point defect sites. A ZT of ~0.78 was obtained at 823 K from SnSe0.7Te0.3, which is an ~11% improvement compared to that of SnSe.
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Affiliation(s)
- Jun-Young Cho
- Department of Materials Science and Engineering, Seoul National University, Seoul 08826, Korea; (J.-Y.C.); (W.C.J.); (S.-H.H.); (M.K.)
| | - Muhammad Siyar
- School of Chemical & Materials Engineering, National University of Sciences and Technology, Islamabad H–12, Pakistan;
| | - Woo Chan Jin
- Department of Materials Science and Engineering, Seoul National University, Seoul 08826, Korea; (J.-Y.C.); (W.C.J.); (S.-H.H.); (M.K.)
| | - Euyheon Hwang
- SKKU Advanced Institute of Nanotechnology (SAINT), Sungkyunkwan University, Suwon 16419, Korea;
| | - Seung-Hwan Bae
- Department of Nano Science and Engineering, Kyungnam University, Changwon 51767, Korea;
| | - Seong-Hyeon Hong
- Department of Materials Science and Engineering, Seoul National University, Seoul 08826, Korea; (J.-Y.C.); (W.C.J.); (S.-H.H.); (M.K.)
| | - Miyoung Kim
- Department of Materials Science and Engineering, Seoul National University, Seoul 08826, Korea; (J.-Y.C.); (W.C.J.); (S.-H.H.); (M.K.)
| | - Chan Park
- Department of Materials Science and Engineering, Seoul National University, Seoul 08826, Korea; (J.-Y.C.); (W.C.J.); (S.-H.H.); (M.K.)
- Research Institute of Advanced Materials, Seoul National University, Seoul 08826, Korea
- Correspondence:
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98
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Zhu G, O'Nolan D, Lively RP. Molecularly Mixed Composite Membranes: Challenges and Opportunities. Chemistry 2019; 26:3464-3473. [PMID: 31549449 DOI: 10.1002/chem.201903519] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2019] [Revised: 09/16/2019] [Indexed: 12/22/2022]
Abstract
The fabrication of porous molecules, such as metal-organic polyhedra (MOPs), porous organic cages (POCs) and others, has given rise to the potential for creating "solid solutions" of molecular fillers and polymers. Such solid solutions circumvent longstanding interface issues associated with mixed matrix membranes (MMMs), and are referred to as molecularly mixed composite membranes (MMCMs) to distinguish them from traditional two-phase MMMs. Early investigations of MMCMs highlight the advantages of solid solutions over MMMs, including dispersion of the filler, anti-plasticization of the polymer network, and removal of deleterious interfacial issues. However, the exact microscopic structure as well as the transport modality in this new class of membrane are not well understood. Moreover, there are clear engineering challenges that need to be addressed for MMCMs to transition into the field. In this Minireview, the authors outline several scientific and technological challenges associated with the aforementioned questions and their suggestions to tackle them.
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Affiliation(s)
- Guanghui Zhu
- School of Chemical & Biomolecular Engineering, Georgia Institute of Technology, 311 Ferst Drive NW, Atlanta, GA, 30332, USA
| | - Daniel O'Nolan
- School of Chemical & Biomolecular Engineering, Georgia Institute of Technology, 311 Ferst Drive NW, Atlanta, GA, 30332, USA
| | - Ryan P Lively
- School of Chemical & Biomolecular Engineering, Georgia Institute of Technology, 311 Ferst Drive NW, Atlanta, GA, 30332, USA
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Lanfant B, Bär F, Mohanta A, Leparoux M. Fabrication of Metal Matrix Composite by Laser Metal Deposition-A New Process Approach by Direct Dry Injection of Nanopowders. Materials (Basel) 2019; 12:E3584. [PMID: 31683592 DOI: 10.3390/ma12213584] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/30/2019] [Revised: 10/23/2019] [Accepted: 10/28/2019] [Indexed: 11/21/2022]
Abstract
Laser Metal Deposition (LMD) offers new perspectives for the fabrication of metal matrix nanocomposites (MMnCs). Current methods to produce MMnCs by LMD systematically involve the premixing of the nanopowders and the micropowders or require in-situ strategies, thereby restricting the possibilities to adjust the nature, content and location of the nano-reinforcement during printing. The objective of this study is to overcome such restrictions and propose a new process approach by direct injection of nanoparticles into a metallic matrix. Alumina (n-Al2O3) nanoparticles were introduced into a titanium matrix by using two different direct dry injection modes in order to locally increase the hardness. Energy dispersive X-ray spectroscopy (EDS) analyses validate the successful incorporation of the n-Al2O3 at chosen locations. Optical and high resolution transmission electron microscopic (HR-TEM) observations as well as X-ray diffraction (XRD) analyses indicate that n-Al2O3 powders are partly or totally dissolved into the Ti melted pool leading to the in-situ formation of a composite consisting of fine α2 lamellar microstructure within a Ti matrix and a solid solution with oxygen. Mechanical tests show a significant increase in hardness with the increase of injected n-Al2O3 amount. A maximum of 620 HV was measured that is almost 4 times higher than the pure LMD-printed Ti structure.
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100
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Czapik A, Jelecki M, Kwit M. Chiral Cocrystal Solid Solutions, Molecular Complexes, and Salts of N-Triphenylacetyl-l-Tyrosine and Diamines. Int J Mol Sci 2019; 20:E5004. [PMID: 31658607 DOI: 10.3390/ijms20205004] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2019] [Revised: 10/06/2019] [Accepted: 10/08/2019] [Indexed: 12/27/2022] Open
Abstract
The molecular recognition process and the ability to form multicomponent supramolecular systems have been investigated for the amide of triphenylacetic acid and l-tyrosine (N-triphenylacetyl-l-tyrosine, TrCOTyr). The presence of several supramolecular synthons within the same amide molecule allows the formation of various multicomponent crystals, where TrCOTyr serves as a chiral host. Isostructural crystals of solvates with methanol and ethanol and a series of binary crystalline molecular complexes with selected organic diamines (1,5-naphthyridine, quinoxaline, 4,4′-bipyridyl, and DABCO) were obtained. The structures of the crystals were planned based on non-covalent interactions (O–H···N or N–H+···O− hydrogen bonds) present in a basic structural motif, which is a heterotrimeric building block consisting of two molecules of the host and one molecule of the guest. The complex of TrCOTyr with DABCO is an exception. The anionic dimers built off the TrCOTyr molecules form a supramolecular gutter, with trityl groups located on the edge and filled by DABCO cationic dimers. Whereas most of the racemic mixtures crystallize as racemic crystals or as conglomerates, the additional tests carried out for racemic N-triphenylacetyl-tyrosine (rac-TrCOTyr) showed that the compound crystallizes as a solid solution of enantiomers.
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