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Nandi SK, Nath SK, Das SK, Murdoch BJ, Ratcliff T, McCulloch DG, Elliman RG. Effect of Interdiffusion and Crystallization on Threshold Switching Characteristics of Nb/Nb 2O 5/Pt Memristors. ACS Appl Mater Interfaces 2023; 15:58613-58622. [PMID: 38051757 DOI: 10.1021/acsami.3c14431] [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: 12/07/2023]
Abstract
The resistive switching response of two terminal metal/oxide/metal devices depends on the stoichiometry of the oxide film, and this is commonly controlled by using a reactive metal electrode to reduce the oxide layer. Here, we investigate compositional and structural changes induced in Nb/Nb2O5 bilayers by thermal annealing at temperatures in the range of 573-973 K and its effect on the volatile threshold switching characteristics of Nb/Nb2O5/Pt devices. Changes in the stoichiometry of the Nb and Nb2O5 films are determined by Rutherford backscattering spectrometry and energy-dispersive X-ray (EDX) mapping of sample cross sections, while the structure of the films is determined by X-ray diffraction, Raman spectroscopy, and transmission electron microscopy (TEM). Such analysis shows that the composition of the Nb and Nb2O5 layers is homogenized by interdiffusion at temperatures less than the crystallization temperature (i.e., >773 K) but that this effectively ceases once the films crystallize. This is explained by comparison with the predictions of a simple diffusion model which shows that the compositional changes are dominated by oxygen diffusion in the amorphous oxide, which is much faster than that in the crystalline phases. We further show that these compositional and structural changes have a significant effect on the electroforming and threshold switching characteristics of the devices, the most significant being a marked increase in their reliability and endurance after crystallization of the oxide films. Finally, we examine the effect of annealing on the quasistatic negative differential resistance characteristics and oscillator dynamics of devices and use a lumped element model to show that this is dominated by changes in the device capacitance resulting from interdiffusion.
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Affiliation(s)
- Sanjoy Kumar Nandi
- Research School of Physics, Australian National University, Canberra, Australian Capital Territory 2601, Australia
| | - Shimul Kanti Nath
- Research School of Physics, Australian National University, Canberra, Australian Capital Territory 2601, Australia
- School of Photovoltaic and Renewable Energy Engineering, University of New South Wales (UNSW Sydney), Kensington, New South Wales 2052, Australia
| | - Sujan Kumar Das
- Research School of Physics, Australian National University, Canberra, Australian Capital Territory 2601, Australia
| | - Billy J Murdoch
- School of Science, RMIT University, Melbourne, Victoria 3001, Australia
| | - Thomas Ratcliff
- Research School of Physics, Australian National University, Canberra, Australian Capital Territory 2601, Australia
| | | | - Robert G Elliman
- Research School of Physics, Australian National University, Canberra, Australian Capital Territory 2601, Australia
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2
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Liu L, Li S, Pan D, Hui D, Zhang X, Li B, Liang T, Shi P, Bahador A, Umeda J, Kondoh K, Li S, Gao L, Wang Z, Li G, Zhang S, Wang R, Chen W. Loss-free tensile ductility of dual-structure titanium composites via an interdiffusion and self-organization strategy. Proc Natl Acad Sci U S A 2023; 120:e2302234120. [PMID: 37399391 PMCID: PMC10334790 DOI: 10.1073/pnas.2302234120] [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] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2023] [Accepted: 05/15/2023] [Indexed: 07/05/2023] Open
Abstract
The deformation-coordination ability between ductile metal and brittle dispersive ceramic particles is poor, which means that an improvement in strength will inevitably sacrifice ductility in dispersion-strengthened metallic materials. Here, we present an inspired strategy for developing dual-structure-based titanium matrix composites (TMCs) that achieve 12.0% elongation comparable to the matrix Ti6Al4V alloys and enhanced strength compared to homostructure composites. The proposed dual-structure comprises a primary structure, namely, a TiB whisker-rich region engendered fine grain Ti6Al4V matrix with a three-dimensional micropellet architecture (3D-MPA), and an overall structure consisting of evenly distributed 3D-MPA "reinforcements" and a TiBw-lean titanium matrix. The dual structure presents a spatially heterogeneous grain distribution with 5.8 μm fine grains and 42.3 μm coarse grains, which exhibits excellent hetero-deformation-induced (HDI) hardening and achieves a 5.8% ductility. Interestingly, the 3D-MPA "reinforcements" show 11.1% isotropic deformability and 66% dislocation storage, which endows the TMCs with good strength and loss-free ductility. Our enlightening method uses an interdiffusion and self-organization strategy based on powder metallurgy to enable metal matrix composites with the heterostructure of the matrix and the configuration of reinforcement to address the strength-ductility trade-off dilemma.
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Affiliation(s)
- Lei Liu
- School of Materials Science and Engineering, Xi’an University of Technology, Xi’an, Shaanxi710048, China
| | - Shufeng Li
- School of Materials Science and Engineering, Xi’an University of Technology, Xi’an, Shaanxi710048, China
- Xi’an Key Laboratory of Advanced Powder Metallurgy Materials and New Technology, Xi’an, Shaanxi710048, China
| | - Deng Pan
- School of Materials Science and Engineering, Xi’an University of Technology, Xi’an, Shaanxi710048, China
- Xi’an Sailong Additive Technology Co., Ltd., Xi’an710018, China
| | - Dongxu Hui
- School of Materials Science and Engineering, Xi’an University of Technology, Xi’an, Shaanxi710048, China
| | - Xin Zhang
- School of Materials Science and Engineering, Xi’an University of Technology, Xi’an, Shaanxi710048, China
- Xi’an Key Laboratory of Advanced Powder Metallurgy Materials and New Technology, Xi’an, Shaanxi710048, China
| | - Bo Li
- School of Materials Science and Engineering, Xi’an University of Technology, Xi’an, Shaanxi710048, China
- Xi’an Key Laboratory of Advanced Powder Metallurgy Materials and New Technology, Xi’an, Shaanxi710048, China
| | - Tianshou Liang
- School of Civil Engineering, Xi’an University of Architecture and Technology, Xi’an, Shaanxi710055, China
| | - Pengpeng Shi
- School of Civil Engineering, Xi’an University of Architecture and Technology, Xi’an, Shaanxi710055, China
- School of Mathematics and Statistics, Ningxia University, Yinchuan, Ningxia750021, China
| | - Abdollah Bahador
- Joining and Welding Research Institute, Osaka University, Ibaraki, Osaka567-0047, Japan
- Razak Faculty of Technology and Informatics, Universiti Teknologi Malaysia, Jalan Sultan Yahya Petra, Kuala Lumpur54100, Malaysia
| | - Junko Umeda
- Joining and Welding Research Institute, Osaka University, Ibaraki, Osaka567-0047, Japan
| | - Katsuyoshi Kondoh
- Joining and Welding Research Institute, Osaka University, Ibaraki, Osaka567-0047, Japan
| | - Shaolong Li
- School of Materials Science and Engineering, Xi’an University of Technology, Xi’an, Shaanxi710048, China
| | - Lina Gao
- School of Materials Science and Engineering, Xi’an University of Technology, Xi’an, Shaanxi710048, China
| | - Zhimao Wang
- Institute of High Energy Physics, Chinese Academy of Sciences, Beijing100049, China
| | - Gang Li
- Institute of High Energy Physics, Chinese Academy of Sciences, Beijing100049, China
| | - Shuyan Zhang
- Centre of Excellence for Advanced Materials, Guangdong, Dongguan523808, China
| | - Ruihong Wang
- School of Materials Science and Engineering, Xi’an University of Technology, Xi’an, Shaanxi710048, China
- Xi’an Key Laboratory of Advanced Powder Metallurgy Materials and New Technology, Xi’an, Shaanxi710048, China
| | - Wenge Chen
- School of Materials Science and Engineering, Xi’an University of Technology, Xi’an, Shaanxi710048, China
- Xi’an Key Laboratory of Advanced Powder Metallurgy Materials and New Technology, Xi’an, Shaanxi710048, China
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3
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Tahani M, Postek E, Sadowski T. Diffusion and Interdiffusion Study at Al- and O-Terminated Al 2O 3/AlSi12 Interface Using Molecular Dynamics Simulations. Materials (Basel) 2023; 16:4324. [PMID: 37374508 DOI: 10.3390/ma16124324] [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] [Subscribe] [Scholar Register] [Received: 04/28/2023] [Revised: 06/02/2023] [Accepted: 06/07/2023] [Indexed: 06/29/2023]
Abstract
The equivalent characteristics of the materials' interfaces are known to impact the overall mechanical properties of ceramic-metal composites significantly. One technological method that has been suggested is raising the temperature of the liquid metal to improve the weak wettability of ceramic particles with liquid metals. Therefore, as the first step, it is necessary to produce the diffusion zone at the interface by heating the system and maintaining it at a preset temperature to develop the cohesive zone model of the interface using mode I and mode II fracture tests. This study uses the molecular dynamics method to study the interdiffusion at the interface of α-Al2O3/AlSi12. The hexagonal crystal structure of aluminum oxide with the Al- and O-terminated interfaces with AlSi12 are considered. A single diffusion couple is used for each system to determine the average main and cross ternary interdiffusion coefficients. In addition, the effect of temperature and the termination type on the interdiffusion coefficients is examined. The results demonstrate that the thickness of the interdiffusion zone is proportional to the annealing temperature and time, and Al- and O-terminated interfaces exhibit similar interdiffusion properties.
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Affiliation(s)
- Masoud Tahani
- Department of Mechanical Engineering, Ferdowsi University of Mashhad, Mashhad 91779-48978, Iran
- Department of Information and Computational Science, Institute of Fundamental Technological Research, Polish Academy of Sciences, Pawińskiego 5B, 02-106 Warsaw, Poland
| | - Eligiusz Postek
- Department of Information and Computational Science, Institute of Fundamental Technological Research, Polish Academy of Sciences, Pawińskiego 5B, 02-106 Warsaw, Poland
| | - Tomasz Sadowski
- Department of Solid Mechanics, Lublin University of Technology, 20-618 Lublin, Poland
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Carvalho PC, Miranda IP, Brandão J, Bergman A, Cezar JC, Klautau AB, Petrilli HM. Correlation of Interface Interdiffusion and Skyrmionic Phases. Nano Lett 2023. [PMID: 37235539 DOI: 10.1021/acs.nanolett.3c00428] [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: 05/28/2023]
Abstract
Magnetic skyrmions are prime candidates for the next generation of spintronic devices. Skyrmions and other topological magnetic structures are known to be stabilized by the Dzyaloshinskii-Moriya interaction (DMI) that occurs when the inversion symmetry is broken in thin films. Here, we show by first-principles calculations and atomistic spin dynamics simulations that metastable skyrmionic states can also be found in nominally symmetric multilayered systems. We demonstrate that this is correlated with the large enhancement of the DMI strength due to the presence of local defects. In particular, we find that metastable skyrmions can occur in Pd/Co/Pd multilayers without external magnetic fields and can be stable even near room temperature conditions. Our theoretical findings corroborate with magnetic force microscopy images and X-ray magnetic circular dichroism measurements and highlight the possibility of tuning the intensity of DMI by using interdiffusion at thin film interfaces.
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Affiliation(s)
- Pamela C Carvalho
- Universidade de São Paulo, Instituto de Física, Rua do Matão, 1371, São Paulo 05508-090, São Paulo, Brazil
| | - Ivan P Miranda
- Department of Physics and Astronomy, Uppsala University, Box 516, Uppsala 75120, Sweden
| | - Jeovani Brandão
- Laboratório Nacional de Luz Síncrotron, Centro Nacional de Pesquisa em Energia e Materiais, Campinas 13083-970, São Paulo, Brazil
| | - Anders Bergman
- Department of Physics and Astronomy, Uppsala University, Box 516, Uppsala 75120, Sweden
| | - Júlio C Cezar
- Laboratório Nacional de Luz Síncrotron, Centro Nacional de Pesquisa em Energia e Materiais, Campinas 13083-970, São Paulo, Brazil
| | - Angela B Klautau
- Faculdade de Física, Universidade Federal do Pará, Belém 66075-110 , Pará, Brazil
- Departamento de Física da Universidade de Aveiro, Aveiro 3810-183, Portugal
| | - Helena M Petrilli
- Universidade de São Paulo, Instituto de Física, Rua do Matão, 1371, São Paulo 05508-090, São Paulo, Brazil
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Li T, Xiong Q, Hu C, Wang C, Zhang N, Lien SY, Gao P. Improving Crystallization and Stability of Perovskite Solar Cells Using a Low-Temperature Treated A-Site Cation Solution in the Sequential Deposition. Molecules 2023; 28:molecules28104103. [PMID: 37241843 DOI: 10.3390/molecules28104103] [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] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2023] [Revised: 05/10/2023] [Accepted: 05/12/2023] [Indexed: 05/28/2023] Open
Abstract
The two-step sequential deposition is a commonly used method by researchers for fabricating perovskite solar cells (PSCs) due to its reproducibility and tolerant preparation conditions. However, the less-than-favorable diffusive processes in the preparation process often result in subpar crystalline quality in the perovskite films. In this study, we employed a simple strategy to regulate the crystallization process by lowering the temperature of the organic-cation precursor solutions. By doing so, we minimized interdiffusion processes between the organic cations and pre-deposited lead iodide (PbI2) film under poor crystallization conditions. This allowed for a homogenous perovskite film with improved crystalline orientation when transferred to appropriate environmental conditions for annealing. As a result, a boosted power conversion efficiency (PCE) was achieved in PSCs tested for 0.1 cm2 and 1 cm2, with the former exhibiting a PCE of 24.10% and the latter of 21.56%, compared to control PSCs, which showed a PCE of 22.65% and 20.69%, respectively. Additionally, the strategy increased device stability, with the cells holding 95.8% and 89.4% of the initial efficiency even after 7000 h of aging under nitrogen or 20-30% relative humidity and 25 °C. This study highlights a promising low-temperature-treated (LT-treated) strategy compatible with other PSCs fabrication techniques, adding a new possibility for temperature regulation during crystallization.
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Affiliation(s)
- Tinghao Li
- CAS Key Laboratory of Design and Assembly of Functional Nanostructures, and Fujian Provincial Key Laboratory of Nanomaterials Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou 350002, China
- College of Chemistry and Materials Science, Fujian Normal University, Fuzhou 350007, China
- Laboratory for Advanced Functional Materials, Xiamen Institute of Rare Earth Materials, Haixi Institute, Chinese Academy of Sciences, Xiamen 361021, China
| | - Qiu Xiong
- CAS Key Laboratory of Design and Assembly of Functional Nanostructures, and Fujian Provincial Key Laboratory of Nanomaterials Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou 350002, China
- Laboratory for Advanced Functional Materials, Xiamen Institute of Rare Earth Materials, Haixi Institute, Chinese Academy of Sciences, Xiamen 361021, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Chongzhu Hu
- CAS Key Laboratory of Design and Assembly of Functional Nanostructures, and Fujian Provincial Key Laboratory of Nanomaterials Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou 350002, China
- Laboratory for Advanced Functional Materials, Xiamen Institute of Rare Earth Materials, Haixi Institute, Chinese Academy of Sciences, Xiamen 361021, China
| | - Can Wang
- CAS Key Laboratory of Design and Assembly of Functional Nanostructures, and Fujian Provincial Key Laboratory of Nanomaterials Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou 350002, China
- Laboratory for Advanced Functional Materials, Xiamen Institute of Rare Earth Materials, Haixi Institute, Chinese Academy of Sciences, Xiamen 361021, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Ni Zhang
- CAS Key Laboratory of Design and Assembly of Functional Nanostructures, and Fujian Provincial Key Laboratory of Nanomaterials Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou 350002, China
- Laboratory for Advanced Functional Materials, Xiamen Institute of Rare Earth Materials, Haixi Institute, Chinese Academy of Sciences, Xiamen 361021, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Shui-Yang Lien
- School of Opto-Electronic and Communication Engineering, Xiamen University of Technology, Xiamen 361024, China
| | - Peng Gao
- CAS Key Laboratory of Design and Assembly of Functional Nanostructures, and Fujian Provincial Key Laboratory of Nanomaterials Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou 350002, China
- Laboratory for Advanced Functional Materials, Xiamen Institute of Rare Earth Materials, Haixi Institute, Chinese Academy of Sciences, Xiamen 361021, China
- University of Chinese Academy of Sciences, Beijing 100049, China
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Razumovsky MI, Bokstein BS, Rodin AO, Khvan AV. Interdiffusion in Refractory Metal System with a BCC Lattice: Ti/TiZrHfNbTaMo. Entropy (Basel) 2023; 25:490. [PMID: 36981378 PMCID: PMC10048413 DOI: 10.3390/e25030490] [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] [Figures] [Subscribe] [Scholar Register] [Received: 01/20/2023] [Revised: 03/10/2023] [Accepted: 03/10/2023] [Indexed: 06/18/2023]
Abstract
Interdiffusion of the elements in a diffusion pair consisting of Ti and an equiatomic high-entropy alloy (HEA) TiZrHfNbTaMo in the temperature range of 1473-1673 K has been studied. A calculated results phase diagram of the alloy by Thermo-Calc 2021-B software as used to determine the temperature stability range of the β-phase in the alloy. Ti-HEA diffusion pairs were obtained by low = temperature welding and then diffusion annealing was carried out at temperatures of 1473, 1573, and 1673 K during 12, 9, and 6 h, respectively. The interdiffusion zone was profiled using electron probe microanalysis (EPMA). The diffusion parameters of the HEA's elements were obtained using Hall's method. An experimental results discussion is given.
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Affiliation(s)
- Mikhail I. Razumovsky
- Department of Physical Chemistry, National University of Science and Technology (NUST) MISIS, 119049 Moscow, Russia
| | - Boris S. Bokstein
- Department of Physical Chemistry, National University of Science and Technology (NUST) MISIS, 119049 Moscow, Russia
| | - Alexey O. Rodin
- Department of Physical Chemistry, National University of Science and Technology (NUST) MISIS, 119049 Moscow, Russia
| | - Alexandra V. Khvan
- Thermochemistry of Materials SRC, National University of Science and Technology (NUST) MISIS, 119049 Moscow, Russia
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Tahani M, Postek E, Motevalizadeh L, Sadowski T. Effect of Vacancy Defect Content on the Interdiffusion of Cubic and Hexagonal SiC/Al Interfaces: A Molecular Dynamics Study. Molecules 2023; 28. [PMID: 36677802 DOI: 10.3390/molecules28020744] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/17/2022] [Revised: 12/27/2022] [Accepted: 01/08/2023] [Indexed: 01/15/2023]
Abstract
The mechanical properties of ceramic-metal nanocomposites are greatly affected by the equivalent properties of the interface of materials. In this study, the effect of vacancy in SiC on the interdiffusion of SiC/Al interfaces is investigated using the molecular dynamics method. The SiC reinforcements exist in the whisker and particulate forms. To this end, cubic and hexagonal SiC lattice polytypes with the Si- and C-terminated interfaces with Al are considered as two samples of metal matrix nanocomposites. The average main and cross-interdiffusion coefficients are determined using a single diffusion couple for each system. The interdiffusion coefficients of the defective SiC/Al are compared with the defect-free SiC/Al system. The effects of temperature, annealing time, and vacancy on the self- and interdiffusion coefficients are investigated. It is found that the interdiffusion of Al in SiC increases with the increase in temperature, annealing time, and vacancy.
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Plyusnina IO, Budylin NY, Shapagin AV. Phase Equilibria, Diffusion and Structure in the Epoxypolycaprolactone System. Polymers (Basel) 2022; 15. [PMID: 36616467 DOI: 10.3390/polym15010117] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2022] [Revised: 12/17/2022] [Accepted: 12/23/2022] [Indexed: 12/29/2022] Open
Abstract
Currently, there is no quantitative approach for the phase structure of cured thermoplastic systems modified with thermoplastic predicting. To solve this problem, we carried out the first stage of the study on a model polycaprolactone-epoxy oligomer (PCL-DGEBA) system. Using differential scanning calorimetry (DSC), refractometry and optical interferometry, a phase diagram for PCL-DGEBA mixtures was constructed, and the Flory-Huggins interaction parameters of PCL-DGEBA mixtures were calculated. The structure of PCL-DGEBA mixtures with different PCL content was analyzed by optical microscopy. The change in the structure formation mechanism with increasing PCL concentration was shown. The diffusion coefficients are calculated by the Motano-Boltzmann method. The values of the apparent activation energy of the viscous flow PCL and of self-diffusion of DGEBA are determined. The obtained data will be used for the in situ curing kinetics and phase equilibria in the diffusion zone investigations in order to develop a quantitative method for predicting the phase structure of cured systems.
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Wang X, Chu M, Wang M, Zhong Q, Chen J, Wang Z, Cao M, Yang H, Cheng T, Chen J, Sham TK, Zhang Q. Unveiling the Local Structure and Electronic Properties of PdBi Surface Alloy for Selective Hydrogenation of Propyne. ACS Nano 2022; 16:16869-16879. [PMID: 36250595 DOI: 10.1021/acsnano.2c06834] [Citation(s) in RCA: 1] [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] [Indexed: 06/16/2023]
Abstract
Building a reliable relationship between the electronic structure of alloyed metallic catalysts and catalytic performance is important but remains challenging due to the interference from many entangled factors. Herein, a PdBi surface alloy structural model, by tuning the deposition rate of Bi atoms relative to the atomic interdiffusion rate at the interface, realizes a continuous modulation of the electronic structure of Pd. Using advanced X-ray characterization techniques, we provide a precise depiction of the electronic structure of the PdBi surface alloy. As a result, the PdBi catalysts show enhanced propene selectivity compared with the pure Pd catalyst in the selective hydrogenation of propyne. The prevented formation of saturated β-hydrides in the subsurface layers and weakened propene adsorption on the surface contribute to the high selectivity. Our work provides in-depth understanding of the electronic properties of surface alloy structure and underlies the study of the electronic structure-performance relationship in bimetallic catalysts.
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Affiliation(s)
- Xuchun Wang
- Institute of Functional Nano & Soft Materials (FUNSOM), Jiangsu Key Laboratory for Carbon-Based Functional Materials and Devices, Soochow University, 199 Ren'Ai Road, Suzhou215123, China
- Department of Chemistry, University of Western Ontario, 1151 Richmond Street, London, OntarioN6A5B7, Canada
| | - Mingyu Chu
- Institute of Functional Nano & Soft Materials (FUNSOM), Jiangsu Key Laboratory for Carbon-Based Functional Materials and Devices, Soochow University, 199 Ren'Ai Road, Suzhou215123, China
| | - Mengwen Wang
- Institute of Functional Nano & Soft Materials (FUNSOM), Jiangsu Key Laboratory for Carbon-Based Functional Materials and Devices, Soochow University, 199 Ren'Ai Road, Suzhou215123, China
| | - Qixuan Zhong
- Institute of Functional Nano & Soft Materials (FUNSOM), Jiangsu Key Laboratory for Carbon-Based Functional Materials and Devices, Soochow University, 199 Ren'Ai Road, Suzhou215123, China
| | - Jiatang Chen
- Department of Chemistry, University of Western Ontario, 1151 Richmond Street, London, OntarioN6A5B7, Canada
| | - Zhiqiang Wang
- Department of Chemistry, University of Western Ontario, 1151 Richmond Street, London, OntarioN6A5B7, Canada
| | - Muhan Cao
- Institute of Functional Nano & Soft Materials (FUNSOM), Jiangsu Key Laboratory for Carbon-Based Functional Materials and Devices, Soochow University, 199 Ren'Ai Road, Suzhou215123, China
| | - Hao Yang
- Institute of Functional Nano & Soft Materials (FUNSOM), Jiangsu Key Laboratory for Carbon-Based Functional Materials and Devices, Soochow University, 199 Ren'Ai Road, Suzhou215123, China
| | - Tao Cheng
- Institute of Functional Nano & Soft Materials (FUNSOM), Jiangsu Key Laboratory for Carbon-Based Functional Materials and Devices, Soochow University, 199 Ren'Ai Road, Suzhou215123, China
| | - Jinxing Chen
- Institute of Functional Nano & Soft Materials (FUNSOM), Jiangsu Key Laboratory for Carbon-Based Functional Materials and Devices, Soochow University, 199 Ren'Ai Road, Suzhou215123, China
| | - Tsun-Kong Sham
- Department of Chemistry, University of Western Ontario, 1151 Richmond Street, London, OntarioN6A5B7, Canada
| | - Qiao Zhang
- Institute of Functional Nano & Soft Materials (FUNSOM), Jiangsu Key Laboratory for Carbon-Based Functional Materials and Devices, Soochow University, 199 Ren'Ai Road, Suzhou215123, China
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Li AB, Miroshnik L, Rummel BD, Balakrishnan G, Han SM, Sinno T. A unified theory of free energy functionals and applications to diffusion. Proc Natl Acad Sci U S A 2022; 119:e2203399119. [PMID: 35648830 DOI: 10.1073/pnas.2203399119] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
SignificanceThe free energy functional is a central component of continuum dynamical models used to describe phase transitions, microstructural evolution, and pattern formation. However, despite the success of these models in many areas of physics, chemistry, and biology, the standard free energy frameworks are frequently characterized by physically opaque parameters and incorporate assumptions that are difficult to assess. Here, we introduce a mathematical formalism that provides a unifying umbrella for constructing free energy functionals. We show that Ginzburg-Landau framework is a special case of this umbrella and derive a generalization of the widely employed Cahn-Hilliard equation. More broadly, we expect the framework will also be useful for generalizing higher-order theories, establishing formal connections to microscopic physics, and coarse graining.
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11
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Howard JD, Evmenenko G, Kim JJ, Warburton RE, Patel S, Fister TT, Buchholz DB, Greeley J, Curtiss LA, Fenter P. Understanding the Solid-State Electrode-Electrolyte Interface of a Model System Using First-Principles Statistical Mechanics and Thin-Film X-ray Characterization. ACS Appl Mater Interfaces 2022; 14:7428-7439. [PMID: 35089684 DOI: 10.1021/acsami.1c20988] [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
Intermixing of atomic species at the electrode-electrolyte boundaries can impact the properties of the interfaces in solid-state batteries. Herein, this work uses first-principles statistical mechanics along with experimental characterization to understand intermixing at the electrode-electrolyte interface. For the model presented in this work, lithium manganese oxide (LiMn2O4, LMO) and lithium lanthanum titanate (Li3xLa2/3-xTiO3, LLTO) are employed as the cathode and electrolyte, respectively. The results of the computational work show that Ti-Mn intermixing at the interface is significant at synthesis temperatures. The experimental results in this work find that, at some critical temperatures between 600 and 700 °C for material preparation, the interface of LLTO-LMO becomes blurred. Calculations predict that the interface is unstable with regard to Ti-Mn intermixing starting at 0 K, suggesting that the critical temperature found in the experiment is related to kinetics. The work overall suggests that, in designing a solid-state battery, the fundamental reactions such as intermixing need to be considered.
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Affiliation(s)
- Jason D Howard
- Materials Science Division, Argonne National Laboratory, Lemont, Illinois 60439, United States
| | - Guennadi Evmenenko
- Department of Materials Science and Engineering, Northwestern University, Evanston, Illinois 60208, United States
| | - Jae Jin Kim
- Chemical Sciences and Engineering Division, Argonne National Laboratory, Lemont, Illinois 60439, United States
| | - Robert E Warburton
- Davidson School of Chemical Engineering, Purdue University, West Lafayette, Indiana 47907, United States
| | - Shane Patel
- Department of Materials Science and Engineering, Northwestern University, Evanston, Illinois 60208, United States
| | - Timothy T Fister
- Chemical Sciences and Engineering Division, Argonne National Laboratory, Lemont, Illinois 60439, United States
| | - D Bruce Buchholz
- Materials Research Science and Engineering Center (MRSEC), Northwestern University, 633 Clark Street, Evanston, Illinois 60208, United States
| | - Jeffrey Greeley
- Davidson School of Chemical Engineering, Purdue University, West Lafayette, Indiana 47907, United States
| | - Larry A Curtiss
- Materials Science Division, Argonne National Laboratory, Lemont, Illinois 60439, United States
| | - Paul Fenter
- Chemical Sciences and Engineering Division, Argonne National Laboratory, Lemont, Illinois 60439, United States
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12
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Chen Z, Zhong J, Yang S, Li S, Liu J, Yu M. The Interdiffusion Behavior of NiCoCrAlYHf Coating Deposited by Arc Ion Plating on Carburized Ni-Based Single Crystal Superalloy. Materials (Basel) 2021; 14:7401. [PMID: 34885557 DOI: 10.3390/ma14237401] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/30/2021] [Revised: 10/29/2021] [Accepted: 11/02/2021] [Indexed: 12/05/2022]
Abstract
In the present study, arc ion plating (AIP) was used to prepare a NiCoCrAlYHf coating (HY5 coating) on a carburized third-generation single-crystal superalloy DD10. The interdiffusion behavior of the carburized superalloy with an HY5 coating was investigated for a 1000 h oxidation time at 1100 °C. Carburization enhanced the interfacial bonding force and improved the microstructure of the NiCoCrAlYHf coating. An interdiffusion zone (IDZ) formed after a 300 h oxidation time, and the formation of a carburized layer effectively suppressed an inward diffusion of cobalt, aluminium, and chromium to the DD10 superalloy as well as an outward diffusion of nickel and refractory elements for instance rhenium and tungsten to the HY5 coating that occurred in static air at 1100 °C. The roles of the carburized layer in affecting thermal cyclic oxidation and element interdiffusion were studied. Subsequently, a modified form of the Boltzmann–Matano analysis was used to present the interdiffusion coefficients of aluminium.
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13
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Duran R, Stender P, Eich SM, Schmitz G. Atom Probe Study of the Miscibility Gap in CuNi Thin Films and Microstructure Development. Microsc Microanal 2021; 28:1-11. [PMID: 34743781 DOI: 10.1017/s1431927621012988] [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: 06/13/2023]
Abstract
The unclear miscibility of CuNi alloys was investigated with atom probe tomography (APT). Multilayered thin film samples were prepared by ion beam sputtering (IBS) and focused ion beam (FIB) shaping. Long-term isothermal annealing treatments in a UHV furnace were conducted at temperatures of 573, 623, and 673 K to investigate the mixing process. The effective interdiffusion coefficient of the nanocrystalline microstructure (including defect diffusion) was determined to be Deff = 1.86 × 10−10 m2/s × exp(−164 kJ/mol/RT) by fitting periodic composition profiles through a Fourier series. In nonequilibrium states, microstructural defects like grain boundaries and precipitates were observed. While at the two higher temperatures total mixing is observed, a clear experimental evidence is found for a miscibility gap at 573 K with the boundary concentrations of 26 and 66 at%. These two compositions are used in a subregular solution model to reconstruct the phase miscibility gap. So, the critical temperature TC of the miscibility gap is found to be 608 K at a concentration of 45 at% Ni.
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Affiliation(s)
- Rüya Duran
- Institute for Materials Science, Chair of Materials Physics, University of Stuttgart, Heisenbergstr. 3, 70569Stuttgart, Germany
| | - Patrick Stender
- Institute for Materials Science, Chair of Materials Physics, University of Stuttgart, Heisenbergstr. 3, 70569Stuttgart, Germany
| | - Sebastian Manuel Eich
- Institute for Materials Science, Chair of Materials Physics, University of Stuttgart, Heisenbergstr. 3, 70569Stuttgart, Germany
| | - Guido Schmitz
- Institute for Materials Science, Chair of Materials Physics, University of Stuttgart, Heisenbergstr. 3, 70569Stuttgart, Germany
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14
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Kim D, Kim K, Kwon H. Interdiffusion and Intermetallic Compounds at Al/Cu Interfaces in Al-50vol.%Cu Composite Prepared by Solid-State Sintering. Materials (Basel) 2021; 14:4307. [PMID: 34361501 DOI: 10.3390/ma14154307] [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: 06/12/2021] [Revised: 07/28/2021] [Accepted: 07/28/2021] [Indexed: 12/02/2022]
Abstract
Al–Cu composites have attracted significant interest recently owing to their lightweight nature and remarkable thermal properties. Understanding the interdiffusion mechanism at the numerous Al/Cu interfaces is crucial to obtain Al–Cu composites with high thermal conductivities. The present study systematically investigates the interdiffusion mechanism at Al/Cu interfaces in relation to the process temperature. Al-50vol.%Cu composite powder, where Cu particles were encapsulated in a matrix of irregular Al particles, was prepared and then sintered at various temperatures from 340 to 500 °C. Intermetallic compounds (ICs) such as CuAl2 and Cu9Al4 were formed at the Al/Cu interfaces during sintering. Microstructural analysis showed that the thickness of the interdiffusion layer, which comprised the CuAl2 and Cu9Al4 ICs, drastically increased above 400 °C. The Vickers hardness of the Al-50vol.%Cu composite sintered at 380 °C was 79 HV, which was 1.5 times that of the value estimated by the rule of mixtures. A high thermal conductivity of 150 W∙m−1∙K−1 was simultaneously obtained. This result suggests that the Al-50vol.%Cu composite material with large number of Al/Cu interfaces, as well as good mechanical strength and heat conductance, can be prepared by solid-state sintering at a low temperature.
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15
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Chandrasekaran A, van de Kruijs RW, Sturm JM, Bijkerk F. Nb Texture Evolution and Interdiffusion in Nb/Si-Layered Systems. ACS Appl Mater Interfaces 2021; 13:31260-31270. [PMID: 34165281 PMCID: PMC8289241 DOI: 10.1021/acsami.1c06210] [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: 04/04/2021] [Accepted: 06/10/2021] [Indexed: 06/13/2023]
Abstract
In this paper, we present a detailed study on the microstructure evolution and interdiffusion in Nb/Si-layered systems. Interlayer formation during the early stages of growth in sputter-deposited Nb-on-Si and Si-on-Nb bilayer systems is studied in vacuo using a high-sensitivity low-energy ion-scattering technique. An asymmetric intermixing behavior is observed, where the Si-on-Nb interface is ∼2× thinner than the Nb-on-Si interface, and it is explained by the surface-energy difference between Nb and Si. During Nb-on-Si growth, the crystallization of the Nb layer occurs around 2.1 nm as-deposited Nb thickness with a strong Nb(110)-preferred orientation, which is maintained up to 3.3 nm as-deposited Nb thickness. A further increase in the Nb layer thickness above 3.3 nm results in a polycrystalline microstructure with a reduced degree of texture. High-resolution cross-sectional transmission electron microscopy imaging is performed on Nb/Si multilayers to study the effect of the Nb layer texture on interdiffusion during low-temperature annealing. Nb/Si multilayers with amorphous 2 nm Nb layers and strongly textured 3 nm thick Nb layers, with limited grain-boundary pathways for diffusion, show no observable interdiffusion during annealing at 200 °C for 8 h, whereas in a Nb/Si multilayer with polycrystalline 4 nm thick Nb layers, a ∼1 nm amorphous Nb/Si interlayer is formed at the Si-on-Nb interface during annealing.
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16
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Xu Z, Yuan K, Zheng Z, Peng H, Liu J. Diffusion Modelling on the Microstructure Evolution in MCrAlY-Superalloy System. J Therm Spray Technol 2021; 30:108-118. [PMID: 38624695 PMCID: PMC7816750 DOI: 10.1007/s11666-020-01151-1] [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] [Figures] [Subscribe] [Scholar Register] [Received: 08/28/2020] [Revised: 12/18/2020] [Accepted: 12/19/2020] [Indexed: 04/17/2024]
Abstract
Elemental diffusion drives the microstructure development in the MCrAlY-superalloy systems at high temperature. In this paper, two diffusion models were built to simulate the diffusion behavior of elements in the coating or in the coating-substrate system. Firstly, a core-shell model was set up to investigate the thermodynamic and kinetic behavior of the localized microstructure. The results of the simulation successfully explained the mechanism of the formation of α(core)-γ'(shell) structure at lower temperature (750 °C) and γ(core)-β(shell) structure at higher temperature (1100 °C). Secondly, a coating-substrate planner model was used to simulate the interdiffusion of elements between the MCrAlY coating and the superalloy substrate. The simulation results in the Ni22Cr10AlY-superalloy system semiquantitatively agreed with the experimental observation. Furthermore, by applying the planner diffusion model, the effect of the MCrAlY coatings on the formation of TCP phases in the substrate was studied, and a GOODMAN map for designing TCP-limited MCrAlY coatings can be provided.
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Affiliation(s)
- Zhenyuan Xu
- BGRIMM Technology Group, Beijing, 100160 China
- BGRIMM Advanced Materials Science & Technology Co., Ltd, Beijing, 102206 China
- Beijing Engineering Technology Research Center of Surface Strengthening and Repairing of Industry Parts, Beijing, 102206 China
| | - Kang Yuan
- BGRIMM Technology Group, Beijing, 100160 China
- BGRIMM Advanced Materials Science & Technology Co., Ltd, Beijing, 102206 China
- Beijing Engineering Technology Research Center of Surface Strengthening and Repairing of Industry Parts, Beijing, 102206 China
| | - Zhaoran Zheng
- BGRIMM Technology Group, Beijing, 100160 China
- BGRIMM Advanced Materials Science & Technology Co., Ltd, Beijing, 102206 China
- Beijing Engineering Technology Research Center of Surface Strengthening and Repairing of Industry Parts, Beijing, 102206 China
| | - Haoran Peng
- BGRIMM Technology Group, Beijing, 100160 China
- BGRIMM Advanced Materials Science & Technology Co., Ltd, Beijing, 102206 China
- Beijing Engineering Technology Research Center of Surface Strengthening and Repairing of Industry Parts, Beijing, 102206 China
| | - Jianming Liu
- BGRIMM Technology Group, Beijing, 100160 China
- BGRIMM Advanced Materials Science & Technology Co., Ltd, Beijing, 102206 China
- Beijing Engineering Technology Research Center of Surface Strengthening and Repairing of Industry Parts, Beijing, 102206 China
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17
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Abstract
Relative role of enthalpy and entropy in the stabilization of senary FCC Al-Co-Cr-Fe-Ni-Mn high entropy alloys was investigated via a high throughput combinatorial solid-to-solid diffusion couple approach. Many off-equiatomic compositions of FCC AlpCoqCrrFesNitMnu were generated by the diffusing Al and Ni in equiatomic Co20Cr20Fe20Ni20Mn20 alloy, i.e., the Al48Ni52 vs Co20Cr20Fe20Ni20Mn20 diffusion couple, annealed at 900°, 1000°, 1100°, and 1200 °C. Above 1000 °C, the solubility limit of Al in off-equiatomic AlpCoqCrrFesNitMnu alloy was determined to be higher than the solubility limit of Al in equiatomic AlxCoCrFeNiMn alloy. Compositions corresponding to the highest solubility limit of Al in off-equiatomic AlpCoqCrrFesNitMnu alloy exhibited a lower free energy of mixing, i.e., higher thermodynamic stability, than equiatomic AlxCoCrFeNiMn compositions, at 1100 °C and above. Therefore, the role of enthalpy was estimated to be significant in achieving higher thermodynamic stability in off-equiatomic alloys, since they always have lower entropy of mixing than their equiatomic counterparts. The magnitude of interdiffusion coefficients of individual elements in Al-Co-Cr-Fe-Ni-Mn alloys were compared to the interdiffusion coefficients in relevant quinary, quaternary, and ternary solvent-based alloys. Interdiffusion coefficients were not necessarily lower in FCC Al-Co-Cr-Fe-Ni-Mn alloys; therefore no sluggish diffusion was observed in FCC HEA, but diffusion of individual elements in BCC Al-Co-Cr-Fe-Ni-Mn alloy followed the sluggish diffusion hypothesis except for Ni. All compositions in the FCC Al-Co-Cr-Fe-Ni-Mn alloy were observed to comply with existing empirical single phase formation rules in high entropy alloys.
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Affiliation(s)
- Abhishek Mehta
- Advanced Materials Processing and Analysis Center Department of Materials Science and Engineering, University of Central Florida, Orlando, Florida 32816, United States
| | - Yongho Sohn
- Advanced Materials Processing and Analysis Center Department of Materials Science and Engineering, University of Central Florida, Orlando, Florida 32816, United States
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18
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Nikulova UV, Chalykh AE. Phase Equilibrium and Interdiffusion in Poly(Vinyl Methyl Ether)-Water System. Polymers (Basel) 2020; 12:E2445. [PMID: 33105811 PMCID: PMC7690603 DOI: 10.3390/polym12112445] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2020] [Revised: 10/19/2020] [Accepted: 10/19/2020] [Indexed: 11/16/2022] Open
Abstract
The phase state diagram of the poly(vinyl methyl ether)-water system in a wide concentration range was obtained by the optical interferometry method. It was shown that this system was characterized by a complicated phase equilibrium with two lower critical solution temperatures, one of which was located in the concentrated region at 21 °C, and the other one in the region of a dilute solution at 31 °C. In the framework of the Flory-Huggins theory, pair interaction parameters were calculated for different parts of the binodal curves, and an attempt was made to reverse simulate the diagram in different conditions. It was suggested that the unusual character of the diagram was associated with the formation of a complicated complex between PVME and water in the middle region of the compositions. Concentration profiles for different temperatures were constructed. For the first time for this system, the numerical values of the diffusion coefficients of poly(vinyl methyl ether) (PVME) into water and water in PVME were obtained. Concentration and temperature dependences of diffusion coefficients were constructed and analyzed. The kinetics of water sorption in PVME was plotted, the clustering integral was calculated, and the approximate number of molecules in a water cluster was estimated. It was shown that in the dilute solution region upon passing through the binodal curve, the interphase disappeared immediately, and the remaining fluctuation of the concentration decreased in size with time. The kinetics of this process was estimated from the change in the size of such a particle.
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Affiliation(s)
- Uliana V. Nikulova
- Frumkin Institute of Physical Chemistry and Electrochemistry Russian Academy of Sciences (IPCE RAS), 119071 Moscow, Russia;
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19
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Qi Y, Richter G, Suadiye E, Kalina M, Rabkin E. Plastic Forming of Metals at the Nanoscale: Interdiffusion-Induced Bending of Bimetallic Nanowhiskers. ACS Nano 2020; 14:11691-11699. [PMID: 32790344 PMCID: PMC7586402 DOI: 10.1021/acsnano.0c04327] [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] [Figures] [Subscribe] [Scholar Register] [Received: 05/24/2020] [Accepted: 08/10/2020] [Indexed: 06/11/2023]
Abstract
Controlled plastic forming of nanoscale metallic objects by applying mechanical load is a challenge, since defect-free nanocrystals usually yield at near theoretical shear strength, followed by stochastic dislocation avalanches that lead to catastrophic failure or irregular, uncontrolled shapes. Herein, instead of mechanical load, we utilize chemical stress from imbalanced interdiffusion to manipulate the shape of nanowhiskers. Bimetallic Au-Fe nanowhiskers with an ultrahigh bending strength were synthesized employing the molecular beam epitaxy technique. The one-sided Fe coating on the defect-free, single-crystalline Au nanowhisker exhibited both single- and polycrystalline regions. Annealing the bimetallic nanowhiskers at elevated temperatures led to gradual change of curvature and irreversible bending. At low homological temperatures at which grain boundary diffusion is a dominant mode of mass transport this irreversible bending was attributed to the grain boundary Kirkendall effect during the diffusion of Au along the grain boundaries in the Fe layer. At higher temperatures and longer annealing times, the bending was dominated by intensive bulk diffusion of Fe into the Au nanowhisker, accompanied by a significant migration of the Au-Fe interphase boundary toward the Fe layers. The irreversible bending was caused by the concentration dependence of the lattice parameter of the Au(Fe) alloy and by the volume effect associated with the interphase boundary migration. The results of this study demonstrate a high potential of chemical interdiffusion in the controlled plastic forming of ultrastrong metal nanostructures. By design of the thickness, microstructure, and composition of the coating as well as the parameters of heat treatment, bimetallic nanowhiskers can be bent in a controlled manner.
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Affiliation(s)
- Yuanshen Qi
- Department
of Materials Science and Engineering, Technion−Israel
Institute of Technology, 3200003 Haifa, Israel
| | - Gunther Richter
- Max
Planck Institute for Intelligent Systems, Heisenbergstrasse 3, 70569 Stuttgart, Germany
| | - Eylül Suadiye
- Max
Planck Institute for Intelligent Systems, Heisenbergstrasse 3, 70569 Stuttgart, Germany
| | - Michael Kalina
- Department
of Materials Science and Engineering, Technion−Israel
Institute of Technology, 3200003 Haifa, Israel
| | - Eugen Rabkin
- Department
of Materials Science and Engineering, Technion−Israel
Institute of Technology, 3200003 Haifa, Israel
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20
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Ma Y, Cullen DA, Goodwill JM, Xu Q, More KL, Skowronski M. Exchange of Ions across the TiN/TaO x Interface during Electroformation of TaO x-Based Resistive Switching Devices. ACS Appl Mater Interfaces 2020; 12:27378-27385. [PMID: 32441092 DOI: 10.1021/acsami.0c06960] [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
The valence change model describes the resistive switching in metal oxide-based devices as due to electroreduction of the oxide and subsequent electromigration of oxygen vacancies. Here, we present cross-sectional X-ray energy-dispersive spectroscopy elemental maps of Ta, O, N, and Ti in electroformed TiN/TaO2.0/TiN structures. O, N, and Ti were exchanged between the anode and the functional oxide in devices formed at high power (∼1 mW), but the exchange was below the detection limit at low power (<0.5 mW). All structures exhibit a similar Ta-enriched and O-depleted filament formed by the elemental segregation in the functional oxide by the temperature gradient. The elemental interchange is interpreted as due to Fick's diffusion caused by high temperatures in the gap of the filament and is not an essential part of electroformation.
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Affiliation(s)
- Yuanzhi Ma
- Department of Materials Science and Engineering, Carnegie Mellon University, 5000 Forbes Avenue, Pittsburgh, Pennsylvania 15213, United States
| | - David A Cullen
- Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
| | - Jonathan M Goodwill
- Department of Materials Science and Engineering, Carnegie Mellon University, 5000 Forbes Avenue, Pittsburgh, Pennsylvania 15213, United States
| | - Qiyun Xu
- Department of Materials Science and Engineering, Carnegie Mellon University, 5000 Forbes Avenue, Pittsburgh, Pennsylvania 15213, United States
| | - Karren L More
- Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
| | - Marek Skowronski
- Department of Materials Science and Engineering, Carnegie Mellon University, 5000 Forbes Avenue, Pittsburgh, Pennsylvania 15213, United States
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21
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Zhan T, Oda K, Ma S, Tomita M, Jin Z, Takezawa H, Mesaki K, Wu YJ, Xu Y, Matsukawa T, Matsuki T, Watanabe T. Effect of Thermal Boundary Resistance between the Interconnect Metal and Dielectric Interlayer on Temperature Increase of Interconnects in Deeply Scaled VLSI. ACS Appl Mater Interfaces 2020; 12:22347-22356. [PMID: 32315529 DOI: 10.1021/acsami.0c03010] [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
Temperature increase in the continuously narrowing interconnects accelerates the performance and reliability degradation of very large scale integration (VLSI). Thermal boundary resistance (TBR) between an interconnect metal and dielectric interlayer has been neglected or treated approximately in conventional thermal analyses, resulting in significant uncertainties in performance and reliability. In this study, we investigated the effects of TBR between an interconnect metal and dielectric interlayer on temperature increase of Cu, Co, and Ru interconnects in deeply scaled VLSI. Results indicate that the measured TBR is significantly higher than the values predicted by the diffuse mismatch model and varies widely from 1 × 10-8 to 1 × 10-7 m2 K W-1 depending on the liner/barrier layer used. Finite element method simulations show that such a high TBR can cause a temperature increase of hundreds of degrees in the future VLSI interconnect. Characterization of interface properties shows the significant importance of interdiffusion and adhesion in TBR. For future advanced interconnects, Ru is better than Co for heat dissipation in terms of TBR. This study provides a guideline for the thermal management in deeply scaled VLSI.
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Affiliation(s)
- Tianzhuo Zhan
- Waseda University, 3-4-1 O̅okubo, Shinjuku-ku, Tokyo 169-8555, Japan
| | - Kaito Oda
- Waseda University, 3-4-1 O̅okubo, Shinjuku-ku, Tokyo 169-8555, Japan
| | - Shuaizhe Ma
- Waseda University, 3-4-1 O̅okubo, Shinjuku-ku, Tokyo 169-8555, Japan
| | - Motohiro Tomita
- Waseda University, 3-4-1 O̅okubo, Shinjuku-ku, Tokyo 169-8555, Japan
| | - Zhicheng Jin
- Waseda University, 3-4-1 O̅okubo, Shinjuku-ku, Tokyo 169-8555, Japan
| | - Hiroki Takezawa
- Waseda University, 3-4-1 O̅okubo, Shinjuku-ku, Tokyo 169-8555, Japan
| | - Kohei Mesaki
- Waseda University, 3-4-1 O̅okubo, Shinjuku-ku, Tokyo 169-8555, Japan
| | - Yen-Ju Wu
- National Institute for Materials Science, 1-2-1 Sengen, Tsukuba 305-0047, Japan
| | - Yibin Xu
- National Institute for Materials Science, 1-2-1 Sengen, Tsukuba 305-0047, Japan
| | - Takashi Matsukawa
- National Institute of Advanced Industrial Science and Technology, 1-1-1 Umezono, Tsukuba, Ibaraki 305-8560, Japan
| | - Takeo Matsuki
- Waseda University, 3-4-1 O̅okubo, Shinjuku-ku, Tokyo 169-8555, Japan
- National Institute of Advanced Industrial Science and Technology, 1-1-1 Umezono, Tsukuba, Ibaraki 305-8560, Japan
| | - Takanobu Watanabe
- Waseda University, 3-4-1 O̅okubo, Shinjuku-ku, Tokyo 169-8555, Japan
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22
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Sousanis A, Poelman D, Smet PF. SmS/EuS/SmS Tri-Layer Thin Films: The Role of Diffusion in the Pressure Triggered Semiconductor-Metal Transition. Nanomaterials (Basel) 2019; 9:E1513. [PMID: 31652914 DOI: 10.3390/nano9111513] [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: 09/16/2019] [Revised: 10/14/2019] [Accepted: 10/20/2019] [Indexed: 11/16/2022]
Abstract
While SmS thin films show an irreversible semiconductor-metal transition upon application of pressure, the switching characteristics can be modified by alloying with other elements, such as europium. This manuscript reports on the resistance response of tri-layer SmS/EuS/SmS thin films upon applying pressure and on the correlation between the resistance response and the interdiffusion between the layers. SmS thin films were deposited by e-beam sublimation of Sm in an H2S atmosphere, while EuS was directly sublimated by e-beam from EuS. Structural properties of the separate thin films were first studied before the deposition of the final nanocomposite tri-layer system. Piezoresistance measurements demonstrated two sharp resistance drops. The first drop, at lower pressure, corresponds to the switching characteristic of SmS. The second drop, at higher pressure, is attributed to EuS, partially mixed with SmS. This behavior provides either a well-defined three or two states system, depending on the degree of mixing. Depth profiling using x-ray photoelectron spectroscopy (XPS) revealed partial diffusion between the compounds upon deposition at a substrate temperature of 400 °C. Thinner tri-layer systems were also deposited to provide more interdiffusion. A higher EuS concentration led to a continuous transition as a function of pressure. This study shows that EuS-modified SmS thin films are possible systems for piezo-electronic devices, such as memory devices, RF (radio frequency) switches and piezoresistive sensors.
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23
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Walther T. Measurement of Diffusion and Segregation in Semiconductor Quantum Dots and Quantum Wells by Transmission Electron Microscopy: A Guide. Nanomaterials (Basel) 2019; 9:E872. [PMID: 31181748 DOI: 10.3390/nano9060872] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/22/2019] [Revised: 06/03/2019] [Accepted: 06/04/2019] [Indexed: 11/16/2022]
Abstract
Strategies are discussed to distinguish interdiffusion and segregation and to measure key parameters such as diffusivities and segregation lengths in semiconductor quantum dots and quantum wells by electron microscopy methods. Spectroscopic methods are usually necessary when the materials systems are complex while imaging methods may suffice for binary or simple ternary compounds where atomic intermixing is restricted to one type of sub-lattice. The emphasis on methodology should assist microscopists in evaluating and quantifying signals from electron micrographs and related spectroscopic data. Examples presented include CdS/ZnS core/shell particles and SiGe, InGaAs and InGaN quantum wells.
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24
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Gobaut B, Orgiani P, Sambri A, di Gennaro E, Aruta C, Borgatti F, Lollobrigida V, Céolin D, Rueff JP, Ciancio R, Bigi C, Das PK, Fujii J, Krizmancic D, Torelli P, Vobornik I, Rossi G, Miletto Granozio F, Scotti di Uccio U, Panaccione G. Role of Oxygen Deposition Pressure in the Formation of Ti Defect States in TiO 2(001) Anatase Thin Films. ACS Appl Mater Interfaces 2017; 9:23099-23106. [PMID: 28613812 DOI: 10.1021/acsami.7b03181] [Citation(s) in RCA: 7] [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: 05/27/2023]
Abstract
We report the study of anatase TiO2(001)-oriented thin films grown by pulsed laser deposition on LaAlO3(001). A combination of in situ and ex situ methods has been used to address both the origin of the Ti3+-localized states and their relationship with the structural and electronic properties on the surface and the subsurface. Localized in-gap states are analyzed using resonant X-ray photoelectron spectroscopy and are related to the Ti3+ electronic configuration, homogeneously distributed over the entire film thickness. We find that an increase in the oxygen pressure corresponds to an increase in Ti3+ only in a well-defined range of deposition pressure; outside this range, Ti3+ and the strength of the in-gap states are reduced.
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Affiliation(s)
- Benoit Gobaut
- Elettra Sincrotrone Trieste S.c.p.A. , Basovizza, I-34012 Trieste, Italy
| | | | - Alessia Sambri
- CNR-SPIN, UOS Napoli , I-80126 Napoli, Italy
- Department of Physics, University of Napoli Federico II , I-80126 Napoli, Italy
| | - Emiliano di Gennaro
- CNR-SPIN, UOS Napoli , I-80126 Napoli, Italy
- Department of Physics, University of Napoli Federico II , I-80126 Napoli, Italy
| | - Carmela Aruta
- CNR-SPIN, UOS Napoli , I-80126 Napoli, Italy
- Department of Physics, University of Napoli Federico II , I-80126 Napoli, Italy
| | | | | | - Denis Céolin
- Synchrotron SOLEIL , L'Orme des Merisiers, BP 48, Saint Aubin, 91192 Gif sur Yvette, France
| | - Jean-Pascal Rueff
- Synchrotron SOLEIL , L'Orme des Merisiers, BP 48, Saint Aubin, 91192 Gif sur Yvette, France
- Laboratoire de Chimie Physique-Matière et Rayonnement, UPMC Université; Paris 06, CNRS, UMR 7614 , F-75005 Paris, France
| | | | - Chiara Bigi
- CNR-IOM, Laboratorio TASC , I-34149 Trieste, Italy
- Department of Physics, University of Milano , I-20133 Milano, Italy
| | - Pranab Kumar Das
- CNR-IOM, Laboratorio TASC , I-34149 Trieste, Italy
- International Centre for Theoretical Physics (ICTP) , I-34100 Trieste, Italy
| | - Jun Fujii
- CNR-IOM, Laboratorio TASC , I-34149 Trieste, Italy
| | | | | | | | - Giorgio Rossi
- CNR-IOM, Laboratorio TASC , I-34149 Trieste, Italy
- Department of Physics, University of Milano , I-20133 Milano, Italy
| | - Fabio Miletto Granozio
- CNR-SPIN, UOS Napoli , I-80126 Napoli, Italy
- Department of Physics, University of Napoli Federico II , I-80126 Napoli, Italy
| | - Umberto Scotti di Uccio
- CNR-SPIN, UOS Napoli , I-80126 Napoli, Italy
- Department of Physics, University of Napoli Federico II , I-80126 Napoli, Italy
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25
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Liu JP, Kirchhoff J, Zhou L, Zhao M, Grapes MD, Dale DS, Tate MD, Philipp HT, Gruner SM, Weihs TP, Hufnagel TC. X-ray reflectivity measurement of interdiffusion in metallic multilayers during rapid heating. J Synchrotron Radiat 2017; 24:796-801. [PMID: 28664887 PMCID: PMC5493026 DOI: 10.1107/s1600577517008013] [Citation(s) in RCA: 2] [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: 12/16/2016] [Accepted: 05/30/2017] [Indexed: 06/07/2023]
Abstract
A technique for measuring interdiffusion in multilayer materials during rapid heating using X-ray reflectivity is described. In this technique the sample is bent to achieve a range of incident angles simultaneously, and the scattered intensity is recorded on a fast high-dynamic-range mixed-mode pixel array detector. Heating of the multilayer is achieved by electrical resistive heating of the silicon substrate, monitored by an infrared pyrometer. As an example, reflectivity data from Al/Ni heated at rates up to 200 K s-1 are presented. At short times the interdiffusion coefficient can be determined from the rate of decay of the reflectivity peaks, and it is shown that the activation energy for interdiffusion is consistent with a grain boundary diffusion mechanism. At longer times the simple analysis no longer applies because the evolution of the reflectivity pattern is complicated by other processes, such as nucleation and growth of intermetallic phases.
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Affiliation(s)
- J. P. Liu
- Department of Materials Science and Engineering, Johns Hopkins University, Baltimore, MD 21218, USA
- School of Materials Science and Engineering, Beijing Institute of Technology, Beijing 100081, People’s Republic of China
| | - J. Kirchhoff
- Department of Materials Science and Engineering, Johns Hopkins University, Baltimore, MD 21218, USA
| | - L. Zhou
- Department of Materials Science and Engineering, Johns Hopkins University, Baltimore, MD 21218, USA
| | - M. Zhao
- Department of Materials Science and Engineering, Johns Hopkins University, Baltimore, MD 21218, USA
| | - M. D. Grapes
- Department of Materials Science and Engineering, Johns Hopkins University, Baltimore, MD 21218, USA
| | - D. S. Dale
- Cornell High Energy Synchrotron Source (CHESS), Cornell University, Ithaca, NY 14853, USA
| | - M. D. Tate
- Department of Physics, Cornell University, Ithaca, NY 14853, USA
| | - H. T. Philipp
- Department of Physics, Cornell University, Ithaca, NY 14853, USA
| | - S. M. Gruner
- Cornell High Energy Synchrotron Source (CHESS), Cornell University, Ithaca, NY 14853, USA
- Department of Physics, Cornell University, Ithaca, NY 14853, USA
- Kavli Institute at Cornell for Nanoscale Science, Cornell University, Ithaca, NY 14853, USA
| | - T. P. Weihs
- Department of Materials Science and Engineering, Johns Hopkins University, Baltimore, MD 21218, USA
| | - T. C. Hufnagel
- Department of Materials Science and Engineering, Johns Hopkins University, Baltimore, MD 21218, USA
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26
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Zhang B, Peng K, Sha X, Li A, Zhou X, Chen Y, Deng Q, Yang D, Ma E, Han X. A Second Amorphous Layer Underneath Surface Oxide. Microsc Microanal 2017; 23:173-178. [PMID: 28228170 DOI: 10.1017/s143192761700006x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Formation of a nanometer-scale oxide surface layer is common when a material is exposed to oxygen-containing environment. Employing aberration-corrected analytical transmission electron microscopy and using single crystal SnSe as an example, we show that for an alloy, a second thin amorphous layer can appear underneath the outmost oxide layer. This inner amorphous layer is not oxide based, but instead originates from solid-state amorphization of the base alloy when its free energy rises to above that of the metastable amorphous state; which is a result of the composition shift due to the preferential depletion of the oxidizing species, in our case, the outgoing Sn reacting with the oxygen atmosphere.
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Affiliation(s)
- Bin Zhang
- 1Beijing Key Laboratory of Microstructure and Property of Advanced Materials,Beijing University of Technology,Beijing 100024,China
| | - Kunlin Peng
- 2College of Physics,Chongqing University,Chongqing 401331,China
| | - Xuechao Sha
- 1Beijing Key Laboratory of Microstructure and Property of Advanced Materials,Beijing University of Technology,Beijing 100024,China
| | - Ang Li
- 1Beijing Key Laboratory of Microstructure and Property of Advanced Materials,Beijing University of Technology,Beijing 100024,China
| | - Xiaoyuan Zhou
- 2College of Physics,Chongqing University,Chongqing 401331,China
| | - Yanhui Chen
- 1Beijing Key Laboratory of Microstructure and Property of Advanced Materials,Beijing University of Technology,Beijing 100024,China
| | - QingSong Deng
- 1Beijing Key Laboratory of Microstructure and Property of Advanced Materials,Beijing University of Technology,Beijing 100024,China
| | - Dingfeng Yang
- 1Beijing Key Laboratory of Microstructure and Property of Advanced Materials,Beijing University of Technology,Beijing 100024,China
| | - Evan Ma
- 3Department of Materials Science and Engineering,Johns Hopkins University,Baltimore,MD 21218,USA
| | - Xiaodong Han
- 1Beijing Key Laboratory of Microstructure and Property of Advanced Materials,Beijing University of Technology,Beijing 100024,China
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27
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Susa A, Bose RK, Grande AM, van der Zwaag S, Garcia SJ. Effect of the Dianhydride/Branched Diamine Ratio on the Architecture and Room Temperature Healing Behavior of Polyetherimides. ACS Appl Mater Interfaces 2016; 8:34068-34079. [PMID: 27960394 DOI: 10.1021/acsami.6b10433] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/19/2023]
Abstract
Traditional polyetherimides (PEIs) are commonly synthesized from an aromatic diamine and an aromatic dianhydride (e.g., 3,4'-oxidianiline (ODA) and 4,4'-oxidiphtalic anhydride (ODPA)) leading to the imide linkage and outstanding chemical, thermal and mechanical properties yet lacking any self-healing functionality. In this work, we have replaced the traditional aromatic diamine by a branched aliphatic fatty dimer diamine (DD1). This led to a whole family of self-healing polymers not containing reversible chemical bonds, capable of healing at (near) room temperature yet maintaining very high elastomeric-like mechanical properties (up to 6 MPa stress and 570% strain at break). In this work, we present the effect of the DD1/ODPA ratio on the general performance and healing behavior of a room temperature healing polyetherimide. A dedicated analysis suggests that healing proceeds in three steps: (i) an initial adhesive step leading to the formation of a relatively weak interface; (ii) a second step at long healing times leading to the formation of an interphase with different properties than the bulk material and (iii) disappearance of the damaged zone leading to full healing. We argue that the fast interfacial adhesive step is due to van der Waals interactions of long dangling alkyl chains followed by an interphase formation due to polymer chain interdiffusion. An increase in DD1/ODPA ratio leads to an increase in the healing kinetics and displacement shift of the first healing step toward lower temperatures. An excess of DD1 leads to the cross-linking of the polymer thereby restricting the necessary mobility for the interphase formation and limiting the self-healing behavior. The results here presented offer a new route for the development of room temperature self-healing thermoplastic elastomers with improved mechanical properties using fatty dimer diamines.
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Affiliation(s)
- A Susa
- Novel Aerospace Materials group, Faculty of Aerospace Engineering, Delft University of Technology , Kluyverweg 1, 2629 HS, Delft, The Netherlands
| | - R K Bose
- Novel Aerospace Materials group, Faculty of Aerospace Engineering, Delft University of Technology , Kluyverweg 1, 2629 HS, Delft, The Netherlands
| | - A M Grande
- Novel Aerospace Materials group, Faculty of Aerospace Engineering, Delft University of Technology , Kluyverweg 1, 2629 HS, Delft, The Netherlands
| | - S van der Zwaag
- Novel Aerospace Materials group, Faculty of Aerospace Engineering, Delft University of Technology , Kluyverweg 1, 2629 HS, Delft, The Netherlands
| | - S J Garcia
- Novel Aerospace Materials group, Faculty of Aerospace Engineering, Delft University of Technology , Kluyverweg 1, 2629 HS, Delft, The Netherlands
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28
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Haase A, Bajt S, Hönicke P, Soltwisch V, Scholze F. Multiparameter characterization of subnanometre Cr/Sc multilayers based on complementary measurements. J Appl Crystallogr 2016; 49:2161-2171. [PMID: 27980515 PMCID: PMC5139997 DOI: 10.1107/s1600576716015776] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [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: 08/16/2016] [Accepted: 10/06/2016] [Indexed: 11/10/2022] Open
Abstract
Cr/Sc multilayer systems can be used as near-normal incidence mirrors for the water window spectral range. It is shown that a detailed characterization of these multilayer systems with 400 bilayers of Cr and Sc, each with individual layer thicknesses <1 nm, is attainable by the combination of several analytical techniques. EUV and X-ray reflectance measurements, resonant EUV reflectance across the Sc L edge, and X-ray standing wave fluorescence measurements were used. The parameters of the multilayer model were determined via a particle-swarm optimizer and validated using a Markov chain Monte Carlo maximum-likelihood approach. For the determination of the interface roughness, diffuse scattering measurements were conducted.
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Affiliation(s)
- Anton Haase
- Physikalisch-Technische Bundesanstalt (PTB), Abbestrasse 2-12, 10587 Berlin, Germany
| | - Saša Bajt
- Photon Science, DESY, Notkestrasse 85, 22607 Hamburg, Germany
| | - Philipp Hönicke
- Physikalisch-Technische Bundesanstalt (PTB), Abbestrasse 2-12, 10587 Berlin, Germany
| | - Victor Soltwisch
- Physikalisch-Technische Bundesanstalt (PTB), Abbestrasse 2-12, 10587 Berlin, Germany
| | - Frank Scholze
- Physikalisch-Technische Bundesanstalt (PTB), Abbestrasse 2-12, 10587 Berlin, Germany
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29
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Tong C, Yun J, Chen YJ, Ji D, Gan Q, Anderson WA. Thermally Diffused Al:ZnO Thin Films for Broadband Transparent Conductor. ACS Appl Mater Interfaces 2016; 8:3985-3991. [PMID: 26807664 DOI: 10.1021/acsami.5b11285] [Citation(s) in RCA: 2] [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: 06/05/2023]
Abstract
Here, we report an approach to realize highly transparent low resistance Al-doped ZnO (AZO) films for broadband transparent conductors. Thin Al films are deposited on ZnO surfaces, followed by thermal diffusion processes, introducing the Al doping into ZnO thin films. By utilizing the interdiffusion of Al, Zn, and O, the chemical state of Al on the surfaces can be converted to a fully oxidized state, resulting in a low sheet resistance of 6.2 Ω/sq and an excellent transparency (i.e., 96.5% at 550 nm and higher than 85% up to 2500 nm), which is superior compared with some previously reported values for indium tin oxide, solution processed AZO, and many transparent conducting materials using novel nanostructures. Such AZO films are also applied as transparent conducting layers for AZO/Si heterojunction solar cells, demonstrating their applications in optoelectronic devices.
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Affiliation(s)
- Chong Tong
- Department of Electrical Engineering, The State University of New York at Buffalo , Buffalo, New York 14260-1920, United States
| | - Juhyung Yun
- Department of Electrical Engineering, Incheon National University , Yeonsu Incheon, 406772, Korea
| | - Yen-Jen Chen
- Department of Electrical Engineering, The State University of New York at Buffalo , Buffalo, New York 14260-1920, United States
| | - Dengxin Ji
- Department of Electrical Engineering, The State University of New York at Buffalo , Buffalo, New York 14260-1920, United States
| | - Qiaoqiang Gan
- Department of Electrical Engineering, The State University of New York at Buffalo , Buffalo, New York 14260-1920, United States
| | - Wayne A Anderson
- Department of Electrical Engineering, The State University of New York at Buffalo , Buffalo, New York 14260-1920, United States
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30
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Abdellah A, Falco A, Schwarzenberger U, Scarpa G, Lugli P. Transfer Printed P3HT/PCBM Photoactive Layers: From Material Intermixing to Device Characteristics. ACS Appl Mater Interfaces 2016; 8:2644-2651. [PMID: 26754413 DOI: 10.1021/acsami.5b10539] [Citation(s) in RCA: 2] [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: 06/05/2023]
Abstract
The fabrication of organic electronic devices involving complex stacks of solution-processable functional materials has proven challenging. Significant material intermixing often occurs as a result of cross-solubility and postdeposition treatments, rendering the realization of even the simplest bilayer architectures rather cumbersome. In this study we investigate the feasibility of a dry transfer printing process for producing abrupt bilayer organic photodiodes (OPDs) and the effect of thermal annealing on the integrity of the bilayer. The process involves the transfer of readily deposited thin films of poly(3-hexylthiophene-2,5-diyl) (P3HT) and [6,6]-phenyl C61 butyric acid methyl ester (PCBM) using a polydimethylsiloxane (PDMS) stamp. Fabricated structures are characterized by means of cross-sectional scanning electron microscopy (SEM), UV/vis absorption spectroscopy, and time-of-flight secondary ion mass spectrometry (TOF-SIMS). Joint consideration of all results unveils abrupt interfaces with no thermal treatment applied and significant material intermixing for samples annealed above 100 °C. The role of the thermally assisted intermixing in determining the performance of complete devices is evaluated through the comparison of J-V characteristics and external quantum efficiencies (EQEs) of identical photodiodes subject to different annealing conditions. It is shown that the performance of such devices approaches the one of bulk heterojunction photodiodes upon thermal annealing at 140 °C for 5 min. Our results demonstrate that transfer printing is a reliable and simple process for the realization of functional multilayers, paving the way for organic electronic devices incorporating complex stacks. It further contributes to a fundamental understanding of material composition within photoactive layers by elucidating the process of thermally assisted intermixing.
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Affiliation(s)
- Alaa Abdellah
- Institute for Nanoelectronics, Technische Universität München , Arcisstrasse 21, D-80333 München, Germany
| | - Aniello Falco
- Institute for Nanoelectronics, Technische Universität München , Arcisstrasse 21, D-80333 München, Germany
| | - Ulrich Schwarzenberger
- Institute for Nanoelectronics, Technische Universität München , Arcisstrasse 21, D-80333 München, Germany
| | - Giuseppe Scarpa
- Institute for Nanoelectronics, Technische Universität München , Arcisstrasse 21, D-80333 München, Germany
| | - Paolo Lugli
- Institute for Nanoelectronics, Technische Universität München , Arcisstrasse 21, D-80333 München, Germany
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31
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Jiang H, He Y, He Y, Li A, Wang H, Zheng Y, Dong Z. Structural characterization and low-temperature properties of Ru/C multilayer monochromators with different periodic thicknesses. J Synchrotron Radiat 2015; 22:1379-1385. [PMID: 26524302 DOI: 10.1107/s1600577515017828] [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: 07/02/2015] [Accepted: 09/23/2015] [Indexed: 06/05/2023]
Abstract
Ru/C multilayer monochromators with different periodic thicknesses were investigated using X-ray grazing-incidence reflectivity, diffuse scattering, Bragg imaging, morphology testing, etc. before and after cryogenic cooling. Quantitative analyses enabled the determination of the key multilayer structural parameters for samples with different periodic thicknesses, especially the influence from the ruthenium crystallization. The results also reveal that the basic structures and reflection performance keep stable after cryogenic cooling. The low-temperature treatment smoothed the surfaces and interfaces and changed the growth characteristic to a low-frequency surface figure. This study helps with the understanding of the structure evolution of multilayer monochromators during cryogenic cooling and presents sufficient experimental proof for using cryogenically cooled multilayer monochromators in a high-thermal-load undulator beamline.
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Affiliation(s)
- Hui Jiang
- Shanghai Synchrotron Radiation Facility, Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Zhangheng Road 239, Pudong District, Shanghai 201204, People's Republic of China
| | - Yan He
- Shanghai Synchrotron Radiation Facility, Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Zhangheng Road 239, Pudong District, Shanghai 201204, People's Republic of China
| | - Yumei He
- Shanghai Synchrotron Radiation Facility, Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Zhangheng Road 239, Pudong District, Shanghai 201204, People's Republic of China
| | - Aiguo Li
- Shanghai Synchrotron Radiation Facility, Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Zhangheng Road 239, Pudong District, Shanghai 201204, People's Republic of China
| | - Hua Wang
- Shanghai Synchrotron Radiation Facility, Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Zhangheng Road 239, Pudong District, Shanghai 201204, People's Republic of China
| | - Yi Zheng
- Shanghai Synchrotron Radiation Facility, Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Zhangheng Road 239, Pudong District, Shanghai 201204, People's Republic of China
| | - Zhaohui Dong
- Shanghai Synchrotron Radiation Facility, Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Zhangheng Road 239, Pudong District, Shanghai 201204, People's Republic of China
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32
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Ito S, Tanaka S, Nishino H. Lead-Halide Perovskite Solar Cells by CH3NH3I Dripping on PbI2-CH3NH3I-DMSO Precursor Layer for Planar and Porous Structures Using CuSCN Hole-Transporting Material. J Phys Chem Lett 2015; 6:881-886. [PMID: 26262667 DOI: 10.1021/acs.jpclett.5b00122] [Citation(s) in RCA: 15] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
The sequential fabrication scheme of the CH3NH3PbI3 layer has been improved to fabricate planar-structure CH3NH3PbI3 perovskite solar cells using CuSCN hole-transporting material (HTM). In the PbI2 layer fabricated by the spin-coating method, at first, small amounts of CH3NH3I (MAI) and DMSO were incorporated as the first-drip precursor layer on a flat TiO2 layer. On the first-drip precursor layers, an MAI solution was applied by either soaking (MAI-soaking method) or dripping using successive spin coating (MAI-dripping). The morphology and crystal transformations were observed by SEM and XRD, respectively. Using the normal sequential MAI-soaking method, we were unable to fabricate planar CH3NH3PbI3 perovskite solar cells with CuSCN HTM. Using the MAI-dripping method, however, a significant photovoltaic effect has been observed to be planar <TiO2/CH3NH3PbI3 perovskite/CuSCN> solar cells.
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Affiliation(s)
- Seigo Ito
- †Department of Electric Engineering and Computer Science, School of Engineering, University of Hyogo, 2167 Shosha, Himeji, Hypogo 671-2280, Japan
| | - Soichiro Tanaka
- †Department of Electric Engineering and Computer Science, School of Engineering, University of Hyogo, 2167 Shosha, Himeji, Hypogo 671-2280, Japan
| | - Hitoshi Nishino
- ‡Energy Technology Laboratories, Osaka Gas Co., Ltd., 6-19-9 Konohana-Ku, Osaka 554-0051, Japan
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33
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Gilbert JB, Rubner MF, Cohen RE. Depth-profiling X-ray photoelectron spectroscopy (XPS) analysis of interlayer diffusion in polyelectrolyte multilayers. Proc Natl Acad Sci U S A 2013; 110:6651-6. [PMID: 23569265 PMCID: PMC3637782 DOI: 10.1073/pnas.1222325110] [Citation(s) in RCA: 133] [Impact Index Per Article: 12.1] [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] [Indexed: 01/27/2023] Open
Abstract
Functional organic thin films often demand precise control over the nanometer-level structure. Interlayer diffusion of materials may destroy this precise structure; therefore, a better understanding of when interlayer diffusion occurs and how to control it is needed. X-ray photoelectron spectroscopy paired with C60(+) cluster ion sputtering enables high-resolution analysis of the atomic composition and chemical state of organic thin films with depth. Using this technique, we explore issues common to the polyelectrolyte multilayer field, such as the competition between hydrogen bonding and electrostatic interactions in multilayers, blocking interlayer diffusion of polymers, the exchange of film components with a surrounding solution, and the extent and kinetics of interlayer diffusion. The diffusion coefficient of chitosan (M = ∼100 kDa) in swollen hydrogen-bonded poly(ethylene oxide)/poly(acrylic acid) multilayer films was examined and determined to be 1.4*10(-12) cm(2)/s. Using the high-resolution data, we show that upon chitosan diffusion into the hydrogen-bonded region, poly(ethylene oxide) is displaced from the film. Under the conditions tested, a single layer of poly(allylamine hydrochloride) completely stops chitosan diffusion. We expect our results to enhance the understanding of how to control polyelectrolyte multilayer structure, what chemical compositional changes occur with diffusion, and under what conditions polymers in the film exchange with the solution.
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Affiliation(s)
| | - Michael F. Rubner
- Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139
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34
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Lee SY, Yoon SF, Ngo ACY, Guo T. Effects of annealing on performances of 1.3-μm InAs-InGaAs-GaAs quantum dot electroabsorption modulators. Nanoscale Res Lett 2013; 8:59. [PMID: 23388169 PMCID: PMC3576240 DOI: 10.1186/1556-276x-8-59] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/11/2013] [Accepted: 01/30/2013] [Indexed: 05/29/2023]
Abstract
In this work, we investigated the effects of quantum dot (QD) annealing (as-grown, 600°C-annealed, and 750°C-annealed) on the preliminary performances of 1.3-μm InAs-InGaAs-GaAs quantum dot electroabsorption modulators (QD-EAMs). Both extinction ratio and insertion loss were found to vary inversely with the annealing temperature. Most importantly, the 3-dB response of the 750°C-annealed lumped-element QD-EAM was found to be 1.6 GHz at zero reverse bias voltage - the lowest reverse bias voltage reported. We believe that this work will be beneficial to researchers working on on-chip integration of QD-EAMs with other devices since energy consumption will be an important consideration.
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Affiliation(s)
- Shuh Ying Lee
- Division of Microelectronics, School of Electrical and Electronic Engineering, Nanyang Technological University, 50 Nanyang Avenue, S1-B2c-21, Singapore, 639798, Singapore
| | - Soon Fatt Yoon
- Division of Microelectronics, School of Electrical and Electronic Engineering, Nanyang Technological University, 50 Nanyang Avenue, S1-B2c-21, Singapore, 639798, Singapore
| | - Andrew CY Ngo
- Patterning and Fabrication Capability Group, Institute of Materials Research and Engineering, Singapore, 117602, Singapore
| | - Tina Guo
- Temasek Laboratories at NTU, Nanyang Technological University, Singapore, 639798, Singapore
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