1
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Kosov AV, Grishenkova OV, Semerikova OL, Vakarin SV, Zaikov YP. Mechanism and Kinetics of the Phase Formation and Dissolution of Na xWO 3 on a Pt Electrode in a Na 2WO 4-WO 3 Melt. MATERIALS (BASEL, SWITZERLAND) 2023; 16:7207. [PMID: 38005136 PMCID: PMC10672828 DOI: 10.3390/ma16227207] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/27/2023] [Revised: 11/11/2023] [Accepted: 11/14/2023] [Indexed: 11/26/2023]
Abstract
A comprehensive study concerning the phase formation mechanism and growth/dissolution kinetics of sodium tungsten bronze crystals during the electrolysis of a 0.8Na2WO4-0.2WO3 melt was carried out. The regularities of deposit formation on a Pt(111) working electrode were investigated experimentally using cyclic voltammetry, chronoamperometry, scanning electron microscopy, and X-ray diffraction analysis. Models have been developed to calculate the current response during the formation, growth and dissolution of a two-phase deposit consisting of NaxWO3 and metallic tungsten or two oxide tungsten bronzes with different sodium content. These models consider mass transfer to the electrode and nuclei; chemical and electrochemical reactions with the participation of polytungstate ions, Na+, Na0, and O2-; as well as the ohmic drop effect. The approach was proposed to describe the dissolution of an NaxWO3 crystal with a nonuniform sodium distribution. The fitting of cyclic voltammograms was performed using the Levenberg-Marquardt algorithm. The NaxWO3 formation/growth/dissolution mechanism was determined. Concentration profiles and diffusion coefficients of [WnO3n]-, reaction rate constants, number density of nuclei, and time dependencies of crystal size were calculated. The proposed approaches and models can be used in other systems for the cyclic voltammogram analysis and study of the mechanism and kinetics of electrode processes complicated by phase formation; parallel and sequential electrochemical and chemical reactions; as well as the formation of a deposit characterized by a nonuniform phase and/or chemical composition.
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Affiliation(s)
- Alexander V. Kosov
- Institute of High Temperature Electrochemistry, Ural Branch of the Russian Academy of Sciences, Yekaterinburg 620990, Russia; (O.L.S.); (S.V.V.); (Y.P.Z.)
| | - Olga V. Grishenkova
- Institute of High Temperature Electrochemistry, Ural Branch of the Russian Academy of Sciences, Yekaterinburg 620990, Russia; (O.L.S.); (S.V.V.); (Y.P.Z.)
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2
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Thangamuthu M, Vankayala K, Xiong L, Conroy S, Zhang X, Tang J. Tungsten Oxide-Based Z-Scheme for Visible Light-Driven Hydrogen Production from Water Splitting. ACS Catal 2023; 13:9113-9124. [PMID: 37441235 PMCID: PMC10334426 DOI: 10.1021/acscatal.3c01312] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2023] [Revised: 06/09/2023] [Indexed: 07/15/2023]
Abstract
The stoichiometric water splitting using a solar-driven Z-scheme approach is an emerging field of interest to address the increasing renewable energy demand and environmental concerns. So far, the reported Z-scheme must comprise two populations of photocatalysts. In the present work, only tungsten oxides are used to construct a robust Z-scheme system for complete visible-driven water splitting in both neutral and alkaline solutions, where sodium tungsten oxide bronze (Na0.56WO3-x) is used as a H2 evolution photocatalyst and two-dimensional (2D) tungsten trioxide (WO3) nanosheets as an O2 evolution photocatalyst. This system efficiently produces H2 (14 μmol h-1) and O2 (6.9 μmol h-1) at an ideal molar ratio of 2:1 in an aqueous solution driven by light, resulting in a remarkably high apparent quantum yield of 6.06% at 420 nm under neutral conditions. This exceptional selective H2 and O2 production is due to the preferential adsorption of iodide (I-) on Na0.56WO3-x and iodate (IO3-) on WO3, which is evidenced by both experiments and density functional theory calculation. The present liquid Z-scheme in the presence of efficient shuttle molecules promises a separated H2 and O2 evolution by applying a dual-bed particle suspension system, thus a safe photochemical process.
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Affiliation(s)
- Madasamy Thangamuthu
- Department
of Chemical Engineering, University College
London, Torrington Place, London WC1E 7JE, U.K.
| | - Kiran Vankayala
- Department
of Chemical Engineering, University College
London, Torrington Place, London WC1E 7JE, U.K.
| | - Lunqiao Xiong
- Department
of Chemical Engineering, University College
London, Torrington Place, London WC1E 7JE, U.K.
| | - Stuart Conroy
- Department
of Chemical and Process Engineering, University
of Strathclyde, Glasgow G1 1XL, U.K.
| | - Xiaolei Zhang
- Department
of Chemical and Process Engineering, University
of Strathclyde, Glasgow G1 1XL, U.K.
| | - Junwang Tang
- Department
of Chemical Engineering, University College
London, Torrington Place, London WC1E 7JE, U.K.
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3
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Chen X, van Huis MA. Formation Pathways of Lath-Shaped WO 3 Nanosheets and Elemental W Nanoparticles from Heating of WO 3 Nanocrystals Studied via In Situ TEM. MATERIALS (BASEL, SWITZERLAND) 2023; 16:1291. [PMID: 36770297 PMCID: PMC9920553 DOI: 10.3390/ma16031291] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/16/2023] [Revised: 01/28/2023] [Accepted: 01/31/2023] [Indexed: 06/18/2023]
Abstract
WO3 is a versatile material occurring in many polymorphs, and is used in nanostructured form in many applications, including photocatalysis, gas sensing, and energy storage. We investigated the thermal evolution of cubic-phase nanocrystals with a size range of 5-25 nm by means of in situ heating in the transmission electron microscope (TEM), and found distinct pathways for the formation of either 2D WO3 nanosheets or elemental W nanoparticles, depending on the initial concentration of deposited WO3 nanoparticles. These pristine particles were stable up to 600 °C, after which coalescence and fusion of the nanocrystals were observed. Typically, the nanocrystals transformed into faceted nanocrystals of elemental body-centered-cubic W after annealing to 900 °C. However, in areas where the concentration of dropcast WO3 nanoparticles was high, at a temperature of 900 °C, considerably larger lath-shaped nanosheets (extending for hundreds of nanometers in length and up to 100 nm in width) were formed that are concluded to be in monoclinic WO3 or WO2.7 phases. These lath-shaped 2D particles, which often curled up from their sides into folded 2D nanosheets, are most likely formed from the smaller nanoparticles through a solid-vapor-solid growth mechanism. The findings of the in situ experiments were confirmed by ex situ experiments performed in a high-vacuum chamber.
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Affiliation(s)
- Xiaodan Chen
- Soft Condensed Matter, Debye Institute for Nanomaterials Science, Utrecht University, Princetonplein 5, 3584 CC Utrecht, The Netherlands
- Electron Microscopy Center, Utrecht University, Universiteitsweg 99, 3584 CG Utrecht, The Netherlands
| | - Marijn A. van Huis
- Soft Condensed Matter, Debye Institute for Nanomaterials Science, Utrecht University, Princetonplein 5, 3584 CC Utrecht, The Netherlands
- Electron Microscopy Center, Utrecht University, Universiteitsweg 99, 3584 CG Utrecht, The Netherlands
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4
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Tu H, Chen D. Aerosol-assisted process to produce sodium tungsten bronze particles from aqueous solutions and effect of particle size on the NIR shielding performance. POWDER TECHNOL 2023. [DOI: 10.1016/j.powtec.2023.118217] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
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5
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Dören R, Panthöfer M, Prädel L, Tremel W, Mondeshki M. Lithium confinement and dynamics in hexagonal and monoclinic tungsten oxide nanocrystals: a 7Li solid state NMR study. NANOSCALE 2022; 14:15348-15363. [PMID: 36218075 DOI: 10.1039/d2nr02492f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
Mixed-valence tungsten bronzes AxWO3 (A = alkali metal, NH4+, etc.) are a series of compounds with adaptive structural and compositional features that make them a hot research topic in thermoelectrics, electrochromics, catalysis or energy applications in battery electrodes. The mixed hexagonal lithium ammonium bronze Lix(NH4)yWO3 is a new member of this structural family whose properties are compared to those of the pure hexagonal tungsten bronze (NH4)xWO3. Surface and structural (nanoconfined) Li+ cations were characterized by 7Li single pulse excitation and 1H-7Li cross-polarization (CP) NMR experiments. CP build-up curves and two-dimensional heteronuclear correlation solid-state NMR techniques provide information about the spatial connectivity between different proton and Li+ species. At 500 °C the bronze structurally transforms from the hexagonal to a monoclinic phase, and defects are formed that are characterized through the Li+ environment. 7Li exchange spectroscopy (EXSY) NMR experiments provide information about the chemical exchange between the lithium species. The measured 7Li T1 and T2 relaxation time constants and the T1/T2 ratio allow characterizing the local strength of Li+ binding.
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Affiliation(s)
- René Dören
- Department Chemie, Johannes Gutenberg-Universität, Duesbergweg 10-14, D-55128 Mainz, Germany.
| | - Martin Panthöfer
- Department Chemie, Johannes Gutenberg-Universität, Duesbergweg 10-14, D-55128 Mainz, Germany.
| | - Leon Prädel
- Max Planck Institute for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany
| | - Wolfgang Tremel
- Department Chemie, Johannes Gutenberg-Universität, Duesbergweg 10-14, D-55128 Mainz, Germany.
| | - Mihail Mondeshki
- Department Chemie, Johannes Gutenberg-Universität, Duesbergweg 10-14, D-55128 Mainz, Germany.
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6
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Zhang Y, Guo D, Li R. Hydrothermal synthesis of Cs0.3WO3 with uniform morphology and size via a dynamic balance of pH. Chem Phys 2022. [DOI: 10.1016/j.chemphys.2022.111710] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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7
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Jiang D, Wang X, Chen R, Sun J, Kang H, Ji D, Liu Y, Wei D. Self-Expanding Molten Salt-Driven Growth of Patterned Transition-Metal Dichalcogenide Crystals. J Am Chem Soc 2022; 144:8746-8755. [PMID: 35508181 DOI: 10.1021/jacs.2c02518] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Transition-metal dichalcogenides (TMDs) have been considered potential materials for the next generation of semiconductors. Realizing controllable growth of TMD crystals is a prerequisite for their future applications, which remains challenging. Here, we reveal a new mechanism of self-expanding molten salt-driven growth for a salt-assisted method and achieve the patterned growth of TMD single-crystal arrays with a size of hundreds of micrometers. Time-of-flight secondary ion mass spectroscopy and other spectroscopy characterizations identify the component of the molten salt solution. Microscopic characterizations reveal the existence of salt solution as an interlayer between a TMD monolayer and the silicon substrate as well as particles along the crystal edge. The edged salt solution serves as a self-expanding liquid substrate, which confines the reactive sites to the localized liquid surface, thus avoiding random nucleation. The surface reaction also assures monolayer crystal formation due to self-limiting growth. Besides, the liquid substrate affords sources and spreads itself continuously owing to the nonwetting effect on TMD crystals, thereby facilitating the continuous extension of the TMD monolayer. This work provides novel insights into the controllable synthesis of TMD monolayers and paves the way for the fabrication of TMD-based integrated functional devices.
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Affiliation(s)
- Dingding Jiang
- Laboratory of Molecular Materials and Devices, Department of Materials Science, Fudan University, Shanghai 200433, China.,State Key Laboratory of Molecular Engineering of Polymers, Department of Macromolecular Science, Fudan University, Shanghai 200433, China
| | - Xuejun Wang
- Laboratory of Molecular Materials and Devices, Department of Materials Science, Fudan University, Shanghai 200433, China.,State Key Laboratory of Molecular Engineering of Polymers, Department of Macromolecular Science, Fudan University, Shanghai 200433, China
| | - Renzhong Chen
- Laboratory of Molecular Materials and Devices, Department of Materials Science, Fudan University, Shanghai 200433, China.,State Key Laboratory of Molecular Engineering of Polymers, Department of Macromolecular Science, Fudan University, Shanghai 200433, China
| | - Jiang Sun
- Laboratory of Molecular Materials and Devices, Department of Materials Science, Fudan University, Shanghai 200433, China.,State Key Laboratory of Molecular Engineering of Polymers, Department of Macromolecular Science, Fudan University, Shanghai 200433, China
| | - Hua Kang
- Laboratory of Molecular Materials and Devices, Department of Materials Science, Fudan University, Shanghai 200433, China.,State Key Laboratory of Molecular Engineering of Polymers, Department of Macromolecular Science, Fudan University, Shanghai 200433, China
| | - Daizong Ji
- Laboratory of Molecular Materials and Devices, Department of Materials Science, Fudan University, Shanghai 200433, China.,State Key Laboratory of Molecular Engineering of Polymers, Department of Macromolecular Science, Fudan University, Shanghai 200433, China
| | - Yunqi Liu
- Laboratory of Molecular Materials and Devices, Department of Materials Science, Fudan University, Shanghai 200433, China.,Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China
| | - Dacheng Wei
- Laboratory of Molecular Materials and Devices, Department of Materials Science, Fudan University, Shanghai 200433, China.,State Key Laboratory of Molecular Engineering of Polymers, Department of Macromolecular Science, Fudan University, Shanghai 200433, China
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8
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Ko E, Jo H, Ok KM. Sr 2Nb 6O 13F 8·4H 2O and Sr 3Nb 2O 2F 12·2H 2O: A Variant of Three-Dimensional Tungsten Bronze and a Polar Molecular Oxide Fluoride. Inorg Chem 2021; 60:7914-7921. [PMID: 34009974 DOI: 10.1021/acs.inorgchem.1c00425] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Crystals of two strontium niobium oxyfluorides, Sr2Nb6O13F8·4H2O and Sr3Nb2O2F12·2H2O, have been grown in phase pure forms via hydrothermal reactions using SrCO3, Nb2O5, and an aqueous HF solution. Single-crystal X-ray diffraction suggests that Sr2Nb6O13F8·4H2O, crystallizing in the orthorhombic centrosymmetric space group, Pbam (No. 55), reveals a new variant of the three-dimensional tungsten bronze structure with three-, four-, and five-membered rings that are composed of corner-sharing NbO2(O/F)2F2, NbO4(O/F)F, NbO3(O/F)3, and SrO3F6 groups. Sr3Nb2O2F12·2H2O with the noncentrosymmetric polar space group, Cmc21 (No. 36), however, reveals a molecular structure consisting of Nb(O/F)2F5 pentagonal bipyramids and two unique Sr2+ cations interacting with F, O/F, and water molecules. Band gaps calculated by the Kubelka-Munk function based on the ultraviolet-visible diffuse-reflectance spectra of Sr2Nb6O13F8·4H2O and Sr3Nb2O2F12·2H2O are estimated to be ca. 3.22 and 4.11 eV, respectively, in which the values are related to the contents of electronegative F atoms and the Nb-O(F)-Nb bond angles influenced by structural distortion. An interesting phase transition reaction from Sr3Nb2O2F12·2H2O to thermodynamically more stable Sr2Nb6O13F8·4H2O occurs under a hydrothermal condition.
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Affiliation(s)
- Euna Ko
- Department of Chemistry, Sogang University, Seoul 04107, Republic of Korea
| | - Hongil Jo
- Department of Chemistry, Sogang University, Seoul 04107, Republic of Korea
| | - Kang Min Ok
- Department of Chemistry, Sogang University, Seoul 04107, Republic of Korea
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9
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Jin L, Zhang Q, Cava RJ. The hydrogen-containing bronzes H0.23WO3 and H0.10ReO3 synthesized via a polymer route. J SOLID STATE CHEM 2021. [DOI: 10.1016/j.jssc.2021.122059] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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10
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Chowdhury R, Tegg L, Keast VJ, Holmes NP, Cooling NA, Vaughan B, Nicolaidis NC, Belcher WJ, Dastoor PC, Zhou X. Plasmonic enhancement of aqueous processed organic photovoltaics. RSC Adv 2021; 11:19000-19011. [PMID: 35478661 PMCID: PMC9033506 DOI: 10.1039/d1ra02328d] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2021] [Accepted: 05/19/2021] [Indexed: 11/21/2022] Open
Abstract
Sodium tungsten bronze (NaxWO3) is a promising alternative plasmonic material to nanoparticulate gold due to its strong plasmonic resonances in both the visible and near-infrared (NIR) regions. Additional benefits include its simple production either as a bulk or a nanoparticle material at a relatively low cost. In this work, plasmonic NaxWO3 nanoparticles were introduced and mixed into the nanoparticulate zinc oxide electron transport layer of a water processed poly(3-hexylthiophene):phenyl-C61-butyric acid methyl ester (P3HT:PC61BM) nanoparticle (NP) based organic photovoltaic device (NP-OPV). The power conversion efficiency of NP-OPV devices with NaxWO3 NPs added was found to improve by around 35% compared to the control devices, attributed to improved light absorption, resulting in an enhanced short circuit current and fill factor. Plasmonic NaxWO3 nanoparticles were introduced to aqueous processed organic photovoltaics with 35% device enhancement.![]()
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11
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Tegg L, Haberfehlner G, Kothleitner G, Keast VJ. Chemical homogeneity and optical properties of individual sodium tungsten bronze nanocubes. Micron 2020; 139:102926. [PMID: 33075611 DOI: 10.1016/j.micron.2020.102926] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2020] [Revised: 08/13/2020] [Accepted: 08/13/2020] [Indexed: 10/23/2022]
Abstract
The sodium tungsten bronzes (NaxWO3) are sub-stoichiometric metal oxides with variable Na content described by x. Methods to determine the overall x of a sample are well-known, but variations of composition within a particle have not yet been explored. In this work, electron microscopy techniques are used to determine the crystallinity and chemical composition of individual Na0.83WO3 nanocubes. The particles are found to be single crystals, with the top and bottom faces of the nanocubes parallel to the {100} planes. Compositional homogeneity is observed within the particles other than an approximately ≈5 nm Na-depletion layer at the edge of the particle. An O-depleted layer, believed to be the result of beam damage, is observed when the beam is scanned slowly over the edge of the particle. Calculations of the plasmon responses using the boundary element method (BEM) show that this depletion layer has a minor impact on the optical properties of the large (190 nm) particle studied of this work, but is expected to have a dramatic impact for small (20 nm) particles.
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Affiliation(s)
- Levi Tegg
- School of Mathematical and Physical Sciences, University of Newcastle, Callaghan, NSW, Australia.
| | - Georg Haberfehlner
- Institute of Electron Microscopy and Nanoanalysis, Graz University of Technology, Graz, Austria
| | - Gerald Kothleitner
- Institute of Electron Microscopy and Nanoanalysis, Graz University of Technology, Graz, Austria; Graz Centre for Electron Microscopy, Graz, Austria
| | - Vicki J Keast
- School of Mathematical and Physical Sciences, University of Newcastle, Callaghan, NSW, Australia
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12
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Tegg L, Keast VJ. Na xWO 3 + TiO 2 nanocomposites as plasmonic photocatalysts for the degradation of organic dyes. NANO EXPRESS 2020. [DOI: 10.1088/2632-959x/aba131] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Abstract
The combination of plasmonic metal nanostructures with semiconductor photocatalysts can improve their photocatalytic efficiency by increasing light absorption and aiding in charge separation. Metallic Na
x
WO3 has been shown to be strongly plasmonic and offers a readily synthesized and low-cost replacement for the noble metals which are conventionally used in plasmonic photocatalysts. In this work, a range of Na
x
WO3 + TiO2 nanocomposites were fabricated. Composites containing both semiconducting (x < 0.25) and metallic (x > 0.25) Na
x
WO3 were prepared. The degradation of rhodamine 6G (R6G) under visible and near infrared (NIR) light illumination was observed only when Na
x
WO3 and TiO2 were both present in the composite. Photocatalytic activity was generally higher in metallic samples than in semiconducting ones, but the sample with the highest activity had a mixture of both. This suggests that a combination of interband transitions and plasmonics-enhanced processes can be used together to catalyse reactions.
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13
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Zimmer A, Gilliot M, Broch L, Boulanger C, Stein N, Horwat D. Morphological and chemical dynamics upon electrochemical cyclic sodiation of electrochromic tungsten oxide coatings extracted by in situ ellipsometry. APPLIED OPTICS 2020; 59:3766-3772. [PMID: 32400504 DOI: 10.1364/ao.389063] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/23/2020] [Accepted: 03/22/2020] [Indexed: 06/11/2023]
Abstract
The sodiation-desodiation process of sputtered amorphous electrochromic tungsten oxide coatings in an aqueous-based medium was simultaneously monitored over 99 cycles by cyclic voltammetry and in situ spectroscopic ellipsometry. This allowed extracting the evolution of optical and geometrical parameters upon cycling. The resulting electrochemical coloring-bleaching process was dynamically fitted in the 1.8-2.8 eV optical range with a four-phase model including a constrained spline parametrization of the dielectric function. This allows real time access to thickness, surface roughness, and dielectric function of ${{\rm Na}_x}\!{{\rm WO}_3}$NaxWO3. The temporal evolution of the latter in the fully colored state was used to highlight the porosity extent of the probed coating of opened morphology. The designed spectroelectrochemical approach was applied to map the temporal evolution of the $\rm Na$Na content (${x}$x in ${{\rm Na}_x}\!{{\rm WO}_3}$NaxWO3) during and between cycles, taking into account the intricate interplay between charge density, thickness, and electrolyte uptake.
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14
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Ikeuchi Y, Takatsu H, Tassel C, Brown CM, Murakami T, Matsumoto Y, Okamoto Y, Kageyama H. Rattling Behavior in a Simple Perovskite NaWO 3. Inorg Chem 2019; 58:6790-6795. [PMID: 31032608 PMCID: PMC7809913 DOI: 10.1021/acs.inorgchem.9b00248] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Rattling phenomena have been observed in materials characterized by a large cage structure but not in a simple ABO3-type perovskite because the size mismatch, if it exists, can be relieved by octahedral rotations. Here, we demonstrate that a stoichiometric perovskite oxide NaWO3, prepared under high pressure, exhibits anharmonic phonon modes associated with low-energy rattling vibrations, leading to suppressed thermal conductivity. The structural analysis and the comparison with the ideal perovskite KWO3 without rattling behavior reveal that the presence of two crystallographic Na1 (2 a) and Na2 (6 b) sites in NaWO3 (space group Im3̅) accompanied by three in-phase WO6 octahedral (a+a+a+) rotations generates an open space Δ ∼ 0.5 Å for the latter site, which is comparable with those of well-known cage compounds of clathrates and filled skutterudites. The observed rattling in NaWO3 is distinct from a quadruple perovskite AA'3B4O12 (A, A': transition metals) where the A (2 a) site with lower multiplicity is the rattler. The present finding offers a general guide to induce rattling of atoms in pristine ABO3 perovskites.
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Affiliation(s)
- Yuya Ikeuchi
- Graduate School of Engineering, Kyoto University, Kyoto 615-8510, Japan
| | - Hiroshi Takatsu
- Graduate School of Engineering, Kyoto University, Kyoto 615-8510, Japan
| | - Cédric Tassel
- Graduate School of Engineering, Kyoto University, Kyoto 615-8510, Japan
| | - Craig M. Brown
- Center for Neutron Research National Institute of Standards and Technology Gaithersburg, Maryland 20899, United States
| | - Taito Murakami
- Graduate School of Engineering, Kyoto University, Kyoto 615-8510, Japan
| | - Yuki Matsumoto
- Graduate School of Engineering, Kyoto University, Kyoto 615-8510, Japan
| | - Yoshihiko Okamoto
- Department of Applied Physics, Nagoya University, Nagoya 464-8603, Japan
| | - Hiroshi Kageyama
- Graduate School of Engineering, Kyoto University, Kyoto 615-8510, Japan
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15
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Yusuf S, Neal L, Bao Z, Wu Z, Li F. Effects of Sodium and Tungsten Promoters on Mg6MnO8-Based Core–Shell Redox Catalysts for Chemical Looping—Oxidative Dehydrogenation of Ethane. ACS Catal 2019. [DOI: 10.1021/acscatal.9b00164] [Citation(s) in RCA: 39] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Seif Yusuf
- Department of Chemical and Biomolecular Engineering, North Carolina State University, 911 Partners Way, Raleigh, North Carolina 27695-7905, United States
| | - Luke Neal
- Department of Chemical and Biomolecular Engineering, North Carolina State University, 911 Partners Way, Raleigh, North Carolina 27695-7905, United States
| | - Zhenghong Bao
- Center for Nanophase Materials Sciences and Chemical Science Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
| | - Zili Wu
- Center for Nanophase Materials Sciences and Chemical Science Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
| | - Fanxing Li
- Department of Chemical and Biomolecular Engineering, North Carolina State University, 911 Partners Way, Raleigh, North Carolina 27695-7905, United States
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16
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Tegg L, Cuskelly D, Keast VJ. Bulk scale fabrication of sodium tungsten bronze nanoparticles for applications in plasmonics. NANOTECHNOLOGY 2018; 29:40LT02. [PMID: 30004026 DOI: 10.1088/1361-6528/aad34b] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
In order to advance plasmon-based technologies, new materials with low damping losses and high chemical stability are needed. In this letter, we report the bulk scale fabrication of sodium tungsten bronze (Na x WO3) nanoparticles with high Na content (x ≤ 0.83) using a furnace-assisted method. Phase purity and morphology is confirmed with x-ray diffraction and scanning electron microscopy. Plasmon responses are characterized using spectrophotometry and spatially-resolved electron energy-loss spectroscopy (EELS) in a scanning transmission electron microscope. Experimental EELS maps of individual nanoparticles show the excitation of distinct plasmon resonances at visible and near-infrared (NIR) frequencies, and these observations are supported by boundary element method simulations. Na x WO3 is a promising alternative material for plasmonics due to its strong plasmon resonances when compared to Au, its simple nanofabrication, and low cost. In particular, their high NIR extinction makes these materials ideal for applications in solar control window coatings or plasmonic photocatalysis.
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Affiliation(s)
- Levi Tegg
- School of Mathematical and Physical Sciences, University of Newcastle, Callaghan, NSW 2308, Australia
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17
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Wang W, Janotti A, Van de Walle CG. Phase transformations upon doping in WO 3. J Chem Phys 2017; 146:214504. [PMID: 28595405 PMCID: PMC5656041 DOI: 10.1063/1.4984581] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2017] [Accepted: 05/11/2017] [Indexed: 12/21/2022] Open
Abstract
High levels of doping in WO3 have been experimentally observed to lead to structural transformation towards higher symmetry phases. We explore the structural phase diagram with charge doping through first-principles methods based on hybrid density functional theory, as a function of doping the room-temperature monoclinic phase transitions to the orthorhombic, tetragonal, and finally cubic phase. Based on a decomposition of energies into electronic and strain contributions, we attribute the transformation to a gain in energy resulting from a lowering of the conduction band on an absolute energy scale.
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Affiliation(s)
- Wennie Wang
- Materials Department, University of California, Santa Barbara, California 93106-5050, USA
| | - Anderson Janotti
- Materials Department, University of California, Santa Barbara, California 93106-5050, USA
| | - Chris G Van de Walle
- Materials Department, University of California, Santa Barbara, California 93106-5050, USA
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18
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Ikeuchi Y, Takatsu H, Tassel C, Goto Y, Murakami T, Kageyama H. High‐Pressure Synthesis of Fully Occupied Tetragonal and Cubic Tungsten Bronze Oxides. Angew Chem Int Ed Engl 2017; 56:5770-5773. [DOI: 10.1002/anie.201701732] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2017] [Indexed: 11/11/2022]
Affiliation(s)
- Yuya Ikeuchi
- Graduate School of Engineering Kyoto University Kyoto 615-8510 Japan
| | - Hiroshi Takatsu
- Graduate School of Engineering Kyoto University Kyoto 615-8510 Japan
| | - Cédric Tassel
- Graduate School of Engineering Kyoto University Kyoto 615-8510 Japan
| | - Yoshihiro Goto
- Graduate School of Engineering Kyoto University Kyoto 615-8510 Japan
| | - Taito Murakami
- Graduate School of Engineering Kyoto University Kyoto 615-8510 Japan
| | - Hiroshi Kageyama
- Graduate School of Engineering Kyoto University Kyoto 615-8510 Japan
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19
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Ikeuchi Y, Takatsu H, Tassel C, Goto Y, Murakami T, Kageyama H. High‐Pressure Synthesis of Fully Occupied Tetragonal and Cubic Tungsten Bronze Oxides. Angew Chem Int Ed Engl 2017. [DOI: 10.1002/ange.201701732] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Yuya Ikeuchi
- Graduate School of Engineering Kyoto University Kyoto 615-8510 Japan
| | - Hiroshi Takatsu
- Graduate School of Engineering Kyoto University Kyoto 615-8510 Japan
| | - Cédric Tassel
- Graduate School of Engineering Kyoto University Kyoto 615-8510 Japan
| | - Yoshihiro Goto
- Graduate School of Engineering Kyoto University Kyoto 615-8510 Japan
| | - Taito Murakami
- Graduate School of Engineering Kyoto University Kyoto 615-8510 Japan
| | - Hiroshi Kageyama
- Graduate School of Engineering Kyoto University Kyoto 615-8510 Japan
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20
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Wang YC, Hsu CH, Hsu YY, Chang CC, Dong C, Chan TS, Kumar K, Liu HL, Chen CL, Wu MK. Structural distortion and electronic states of Rb doped WO3 by X-ray absorption spectroscopy. RSC Adv 2016. [DOI: 10.1039/c6ra21777j] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Rubidium tungsten bronzes (RbxWO3) have recently attracted much attention due to their intriguing phenomena, such as complex structural phase transitions, strong electron–phonon coupling, and superconducting properties.
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Affiliation(s)
- Y. C. Wang
- Institute of Physics
- Academia Sinica
- Taipei
- Taiwan
- Department of Physics
| | - C. H. Hsu
- Institute of Physics
- Academia Sinica
- Taipei
- Taiwan
| | - Y. Y. Hsu
- Program for Science and Technology of Accelerator Light Source
- National Chiao Tung University
- Hsinchu
- Taiwan
- National Synchrotron Radiation Research Center
| | - C. C. Chang
- Institute of Physics
- Academia Sinica
- Taipei
- Taiwan
| | - C. L. Dong
- National Synchrotron Radiation Research Center
- Hsinchu
- Taiwan
- Department of Physics
- Tamkang University
| | - T. S. Chan
- National Synchrotron Radiation Research Center
- Hsinchu
- Taiwan
| | - Krishna Kumar
- Department of General Studies
- Physics Division
- Jubail Industrial College (JIC)
- Jubail Industrial City 31961
- Kingdom of Saudi Arabia
| | - H. L. Liu
- Department of Physics
- National Taiwan Normal University
- Taipei
- Taiwan
| | - C. L. Chen
- Institute of Physics
- Academia Sinica
- Taipei
- Taiwan
- National Synchrotron Radiation Research Center
| | - M. K. Wu
- Institute of Physics
- Academia Sinica
- Taipei
- Taiwan
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21
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Ben-Dor L, Conroy LE. Similarity Between the Tungsten Bronzes and the Dioxides of W and Mo. Isr J Chem 2013. [DOI: 10.1002/ijch.196900092] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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22
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Chen B, Laverock J, Piper LFJ, Preston ARH, Cho SW, DeMasi A, Smith KE, Scanlon DO, Watson GW, Egdell RG, Glans PA, Guo JH. The band structure of WO3 and non-rigid-band behaviour in Na0.67WO3 derived from soft x-ray spectroscopy and density functional theory. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2013; 25:165501. [PMID: 23553445 DOI: 10.1088/0953-8984/25/16/165501] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
The electronic structure of single-crystal WO3 and Na0.67WO3 (a sodium-tungsten bronze) has been measured using soft x-ray absorption and resonant soft x-ray emission oxygen K-edge spectroscopies. The spectral features show clear differences in energy and intensity between WO3 and Na0.67WO3. The x-ray emission spectrum of metallic Na0.67WO3 terminates in a distinct Fermi edge. The rigid-band model fails to explain the electronic structure of Na0.67WO3 in terms of a simple addition of electrons to the conduction band of WO3. Instead, Na bonding and Na 3s-O 2p hybridization need to be considered for the sodium-tungsten bronze, along with occupation of the bottom of the conduction band. Furthermore, the anisotropy in the band structure of monoclinic γ-WO3 revealed by the experimental spectra with orbital-resolved geometry is explained via density functional theory calculations. For γ-WO3 itself, good agreement is found between the experimental O K-edge spectra and the theoretical partial density of states of O 2p orbitals. Indirect and direct bandgaps of insulating WO3 are determined from extrapolating separations between spectral leading edges and accounting for the core-hole energy shift in the absorption process. The O 2p non-bonding states show upward band dispersion as a function of incident photon energy for both compounds, which is explained using the calculated band structure and experimental geometry.
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Affiliation(s)
- B Chen
- Department of Physics, Boston University, Boston, MA 02215, USA.
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23
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Park KS, Kim HG, Kim YH, Park CH, Kim KD. The preparation and characterization of NaWO3 particles for heat shielding by Taguchi optimization method. Chem Eng Res Des 2011. [DOI: 10.1016/j.cherd.2011.04.008] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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24
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Isakov IV, Kalyukanov AI, Volkov VL, Ozerov RP, Fykin LE. Neutron diffraction study of the atomic structure of cubic sodium-tungsten bronze (Na0.69WO3) single crystal. CRYSTALLOGR REP+ 2011. [DOI: 10.1134/s1063774511030096] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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25
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Guo C, Yin S, Yan M, Sato T. Facile synthesis of homogeneous CsxWO3 nanorods with excellent low-emissivity and NIR shielding property by a water controlled-release process. ACTA ACUST UNITED AC 2011. [DOI: 10.1039/c0jm04379f] [Citation(s) in RCA: 125] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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26
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Mamak M, Choi SY, Stadler U, Dolbec R, Boulos M, Petrov S. Thermal plasma synthesis of tungsten bronze nanoparticles for near infra-red absorption applications. ACTA ACUST UNITED AC 2010. [DOI: 10.1039/c0jm02169e] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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27
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Debnath T, Rüscher CH, Gesing TM, Koepke J, Hussain A. Solid-state synthesis in the system Na0.8NbyW1−yO3 with 0⩽y⩽0.4: A new phase, Na0.5NbO2.75, with perovskite-type structure. J SOLID STATE CHEM 2008. [DOI: 10.1016/j.jssc.2008.01.027] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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28
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Ingham B, Chong SV, Tallon JL. Layered Tungsten Oxide-Based Organic−Inorganic Hybrid Materials: An Infrared and Raman Study. J Phys Chem B 2005; 109:4936-40. [PMID: 16863150 DOI: 10.1021/jp045066l] [Citation(s) in RCA: 94] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Tungsten oxide-organic layered hybrid materials have been studied by infrared and Raman spectroscopy and demonstrate a difference in bonding nature as the length of the interlayer organic "spacer" molecule is increased. Ethylenediamine-tungsten oxide clearly displays a lack of terminal -NH3(+) ammonium groups which appear in hybrids with longer organic molecules, thus indicating that the longer chains are bound by electrostatic interactions as well as or in place of the hydrogen bonding that must be present in the shorter chain ethylenediamine hybrids. The presence of organic molecules between the tungsten oxide layers, compared with the layered tungstic acid H2WO4, shows a decrease in the apical W=O bond strength, as might be expected from the aforementioned electrostatic interaction.
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Affiliation(s)
- Bridget Ingham
- Victoria University of Wellington, P.O. Box 600, Wellington, New Zealand.
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29
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Hill MD, Egdell RG. The sodium tungsten bronzes: a study of the changes in electronic structure with composition using high-resolution electron spectroscopy. ACTA ACUST UNITED AC 2000. [DOI: 10.1088/0022-3719/16/32/013] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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30
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Tsang C, Lai SY, Manthiram A. Reduction of Aqueous Na(2)WO(4) by NaBH(4) at Ambient Temperatures To Obtain Lower Valent Tungsten Oxides. Inorg Chem 1997; 36:2206-2210. [PMID: 11669846 DOI: 10.1021/ic9610039] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A systematic investigation of the reduction of aqueous Na(2)WO(4) with aqueous NaBH(4) at ambient temperatures reveals the formation of several lower valent tungsten oxides such as the tetragonal (x < 0.38) and cubic (x > 0.43) tungsten bronzes Na(x)()WO(3) and the binary oxides WO(2) and W(24)O(68). The nature of the product formed is influenced both by the (i) reducing power of NaBH(4), which is controlled by the volume and concentration of the borohydride and the reaction pH, and (ii) the degree of condensation of the tungstate ions, which is controlled by the reaction pH. Although the reducing power of NaBH(4) increases with decreasing pH, an increasing degree of condensation of the tungstate tends to lower the degree of reduction in many instances. The as-prepared samples are amorphous as revealed by X-ray diffraction and crystallize around 450 degrees C as revealed by differential scanning calorimerty. The tungsten bronzes undergo interesting crystal-chemical changes with the temperature of heating.
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Affiliation(s)
- C. Tsang
- Center for Materials Science & Engineering, ETC 9.104, The University of Texas at Austin, Austin, Texas 78712
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31
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Hjelm A, Granqvist CG, Wills JM. Electronic structure and optical properties of WO3, LiWO3, NaWO3, and HWO3. PHYSICAL REVIEW. B, CONDENSED MATTER 1996; 54:2436-2445. [PMID: 9986090 DOI: 10.1103/physrevb.54.2436] [Citation(s) in RCA: 94] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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32
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Kielwein M, Saiki K, Roth G, Fink J, Paasch G, Egdell RG. High-energy electron-energy-loss study of sodium-tungsten bronzes. PHYSICAL REVIEW. B, CONDENSED MATTER 1995; 51:10320-10335. [PMID: 9977725 DOI: 10.1103/physrevb.51.10320] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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34
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GRANOVIST CLAESGÖRAN. Electrochromic Tungsten-Oxide–Based Thin Films: Physics, Chemistry, and Technology. ACTA ACUST UNITED AC 1993. [DOI: 10.1016/b978-0-12-533017-6.50010-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/17/2023]
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35
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Technology and Physics of Thin Film Insertion Compounds. ACTA ACUST UNITED AC 1990. [DOI: 10.1007/978-1-4899-2263-2_12] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
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36
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Dubson MA, Holcomb DF. NMR study of the metal-insulator transition in the compensated sodium-tungsten bronze, NaxTayW1-yO3. PHYSICAL REVIEW. B, CONDENSED MATTER 1986; 34:25-35. [PMID: 9939230 DOI: 10.1103/physrevb.34.25] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/11/2023]
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37
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Hollinger G, Pertosa P, Doumerc JP, Himpsel FJ, Reihl B. Metal-nonmetal transition in tungsten bronzes: A photoemission study. PHYSICAL REVIEW. B, CONDENSED MATTER 1985; 32:1987-1991. [PMID: 9937261 DOI: 10.1103/physrevb.32.1987] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/11/2023]
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38
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Wolfram T, Sutcu L. x dependence of the electronic properties of cubic NaxWO3. PHYSICAL REVIEW. B, CONDENSED MATTER 1985; 31:7680-7687. [PMID: 9935710 DOI: 10.1103/physrevb.31.7680] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/11/2023]
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39
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Egdell R, Hill M. A study of the sodium tungsten bronzes by high-resolution electron energy loss spectroscopy. Chem Phys Lett 1982. [DOI: 10.1016/0009-2614(82)83163-1] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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McColm I, Wilson S. Vegard relationships in cubic oxide bronzes with the perovskite structure. J SOLID STATE CHEM 1982. [DOI: 10.1016/0022-4596(82)90206-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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McColm I, Wilson S. The reaction of cubic sodium tungsten bronzes, NaxWO3, with metallic iron. J SOLID STATE CHEM 1980. [DOI: 10.1016/0022-4596(80)90219-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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45
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Atoji M. Domain and surface structures of sodium tungsten bronzes, NaxWo3 (0.4 < x < 1). J SOLID STATE CHEM 1980. [DOI: 10.1016/0022-4596(80)90013-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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46
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McColm I, Wilson S. Composition-dependent microhardness and its relationship to bonding in sodium tungsten bronzes. J SOLID STATE CHEM 1978. [DOI: 10.1016/0022-4596(78)90157-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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47
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Hoppmann G, Salje E. Optical and electrical properties of H+ doped WO3 single crystals. ACTA ACUST UNITED AC 1976. [DOI: 10.1002/pssa.2210370263] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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48
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Takusagawa F, Jacobson RA. Crystal structure studies of tetragonal sodium tungsten bronzes, NaxWO3. I. Na0.33WO3 and Na0.48WO3. J SOLID STATE CHEM 1976. [DOI: 10.1016/0022-4596(76)90092-x] [Citation(s) in RCA: 34] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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50
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