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Hydrogen Reduction of Tungsten Oxides Part Ⅰ:Reduction of WO_(2.90),W_(20)O_(58) and WO_3 被引量:1
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作者 Tang Xinhe Cao Rongjiang Chen Hongyu Sun Xu General Research Institute for Non-ferrous Metals,Beijing Tang Xinhe now works in Institute of Chemical Metallurgy,Academia Sinica,P.O.Box 353,Beijing,China. 《Rare Metals》 SCIE EI CAS CSCD 1989年第4期1-5,共5页
The hydrogen reduction of tungsten oxides WO_(2.90),W_(20)O_(58) and WO_3 were directly studied using high temperature X-ray diffraction analysis.The differences between tetragonal WO_(2.90) and monoclinic W_(20)O_(58... The hydrogen reduction of tungsten oxides WO_(2.90),W_(20)O_(58) and WO_3 were directly studied using high temperature X-ray diffraction analysis.The differences between tetragonal WO_(2.90) and monoclinic W_(20)O_(58) were discussed.Pure β-W was obtained from oxide WO_(2.90),while there appears small amount of WO_2 during the reduction of W_(20)O_(58) to β-W. 展开更多
关键词 HZ Reduction of WO Hydrogen Reduction of tungsten oxides Part
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Hydrogen Reduction of Tungsten Oxides Part Ⅱ:Reduction of WO_(2.72) and WO_2,Transformation of β-W 被引量:1
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作者 Tang Xinhe Cao Rongjiang Chen Hongyu Sun Xu General Research Institute for Non-ferrous Metals,Beijing 《Rare Metals》 SCIE EI CAS CSCD 1990年第1期5-9,共5页
The hydrogen reduction of tungsten oxides WO_(272)and WO_2 were studied directly using high-temperature X-ray diffraction analysis,The pure β-W was obtained from the reduction of WO_(272)The transformation of β-W to... The hydrogen reduction of tungsten oxides WO_(272)and WO_2 were studied directly using high-temperature X-ray diffraction analysis,The pure β-W was obtained from the reduction of WO_(272)The transformation of β-W to x-W was also studied in both hydrogen and nitrogen.The forming condition of β-W from WO_2 was discussed.Finally.a complete schematic diagram of reduction of tungsten oxides was given in this paper. 展开更多
关键词 and WO2 Transformation of Hydrogen Reduction of tungsten oxides Part Reduction of WO
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Towards an optical coupler using fine-wire:a study of the photovoltaic effect of a heterojunction formed in a single fine-wire of tungsten oxides
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作者 陈尚辉 陈建 +1 位作者 邓少芝 许宁生 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第3期557-562,共6页
Nanodevices using the photovoltaic effect of a single nanowire have attracted growing interest. In this paper, we consider potential applications of the photovoltaic effect to optical signal coupling and optical power... Nanodevices using the photovoltaic effect of a single nanowire have attracted growing interest. In this paper, we consider potential applications of the photovoltaic effect to optical signal coupling and optical power transmission, and report on the realization of a heterojunction formed between WO2 and WO3 in a fine-wire having a diameter on the micrometer scale. Using a laser beam of 514.5 nm as a signal source, the WO2-WO3 heterojunction yields a maximum output power of up to 37.4 pico watt per heterojunction. Fast responses (less than a second) of both photovoltaic voltage and current are also observed. In addition, we demonstrate that it is a simple and effective way to adapt a commercial Raman spectrometer for the combined functions of fabrication, material characterization and photovottaic measurement of an optical signal coupler and optical power transmitter based on a fine-wire. Our results show an attractive perspective of developing nanowire or fine-wire elements for coupling optical signals into and for powering a nanoelectronic or nano-optoelectronic integrated circuit that works under the condition of preventing it from directly electrically connecting with the optical coupler. 展开更多
关键词 optical coupler HETEROJUNCTION tungsten oxide fine-wire PHOTOVOLTAIC
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In situ sulfur-doped mesoporous tungsten oxides for gas sensing toward benzene series
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作者 Yu Deng Yan Liu +3 位作者 Yonghui Deng Jinsheng Cheng Yidong Zou Wei Luo 《Chinese Chemical Letters》 SCIE CAS CSCD 2024年第7期502-507,共6页
Benzene series as highly toxic gases have inevitably entered human life and produce great threat to human health and ecological environment,and thus it is distinctly meaningful to monitor benzene series with quickly,r... Benzene series as highly toxic gases have inevitably entered human life and produce great threat to human health and ecological environment,and thus it is distinctly meaningful to monitor benzene series with quickly,real-time and efficient technique.Herein,novel sulfur-doped mesoporous WO_(3)materials were synthesized via classical in-situ solvent evaporation induced co-assembly strategy combined with doping engineering,which possessed highly crystallized frameworks,high specific surface area(40.9–63.8 m^(2)/g)and uniform pore size(~18 nm).Benefitting from abundant oxygen vacancy and defects via S-doping,the tailored mesoporous S/m WO_(3)exhibited excellent benzene sensing performance,including high sensitivity(50 ppm vs.48),low detection limit(ca.500 ppb),outstanding selectivity and favorable stability.In addition,the reduction of band gap resulted from S-doping promotes the carrier migration in the sensing materials and the reaction at the gas–solid sensing interfaces.It provides brand-new approach to design sensitive materials with multiple reaction sites. 展开更多
关键词 Mesoporous materials Benzene series tungsten oxides Sulfur doping Gas sensor
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Quantifying structural distortion manipulation for desired perovskite phase:PartⅠ.Paradigm demonstration in tungsten oxides 被引量:1
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作者 Cheng Fang Hong Wang Siqi Shi 《Journal of Materiomics》 SCIE CSCD 2024年第2期293-303,共11页
Slight distortions can cause dramatic changes in the properties of crystalline perovskite materials and their derivatives.Due to the numerous types of distortions and unclarified distortion-structure relations,a quant... Slight distortions can cause dramatic changes in the properties of crystalline perovskite materials and their derivatives.Due to the numerous types of distortions and unclarified distortion-structure relations,a quantitative distortion manipulation for the desired crystalline phase of perovskite materials suitable for various application remains challenging.Here,by establishing parameter sets to systematically describe the types,magnitudes and positional relations involved in distortions,we are able to interpret the structural regulations and manipulation strategies in 7 reported crystal systems.Through the con-struction of distortion-phase-property functional curves,we further propose a paradigm to quantify the structural distortion manipulation for desired perovskite phases.Using the example of perovskite-like tungsten oxides,we successfully quantify their volume shrinkage and symmetry increase during lith-iation.This work verifies that the complicated research and development of perovskite materials can be simplified into a mathematical problem solving process,which will inspire researchers with different backgrounds to participate,especially mathematicians and computer scientists. 展开更多
关键词 Distortion manipulation Distortion-phase-property function Coordination polyhedron tungsten oxide PEROVSKITE
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Atomic tailoring-induced deficiency in tungsten oxides for high-performance energy-related devices
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作者 Jing-Huang Lin Yao-Tian Yan +1 位作者 Jun-Lei Qi Chen-Yang Zha 《Tungsten》 EI CSCD 2024年第2期269-277,共9页
Nowadays,tungsten oxides,as a typical transition metal oxide,are widely and intensively investigated owing to their excellent material properties and device properties.Controlling oxygen defi ciency in tungsten oxides... Nowadays,tungsten oxides,as a typical transition metal oxide,are widely and intensively investigated owing to their excellent material properties and device properties.Controlling oxygen defi ciency in tungsten oxides is typically the key to enhance their performances for a variety of critical technological applications.With a gradual increase of oxygen defi ciency,various non-stoichiometric tungsten oxides can be formed by re-adjustment of the atomic arrangement,which exhibits superior performances than their traditional stoichiometric counterparts.This review mainly focuses on the recent advances in oxygen-defi cient tungsten oxides from the point of atomic structures,including the forming mechanism of non-stoichiometric tungsten oxides and the superiority of these oxygen-defi cient tungsten oxides in energy-related devices.Finally,the challenge and perspective of oxygen-defi cient tungsten oxides are also discussed. 展开更多
关键词 Oxygen defi ciency tungsten oxide Atomic structures CATALYST Storage
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Sol-gel-based porous Ti-doped tungsten oxide films for high-performance dual-band electrochromic smart windows 被引量:1
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作者 Qiancheng Meng Sheng Cao +6 位作者 Juquan Guo Qingke Wang Ke Wang Tao Yang Ruosheng Zeng Jialong Zhao Bingsuo Zou 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第2期137-143,I0004,共8页
Dual-band electrochromic smart windows(DESWs)with independent control of the transmittance of near-infrared and visible light show great potential in the application of smart and energy-saving buildings.The current st... Dual-band electrochromic smart windows(DESWs)with independent control of the transmittance of near-infrared and visible light show great potential in the application of smart and energy-saving buildings.The current strategy for building DESWs is to screen materials for composite or prepare plasmonic nanocrystal films.These rigorous preparation processes seriously limit the further development of DESWs.Herein,we report a facile and effective sol-gel strategy using a foaming agent to achieve porous Ti-doped tungsten oxide film for the high performance of DESWs.The introduction of foaming agent polyvinylpyrrolidone during the film preparation can increase the specific surface area and free carrier concentration of the films and enhance their independent regulation ability of near-infrared electrochromism.As a result,the optimal film shows excellent dual-band electrochromic properties,including high optical modulation(84.9%at 633 nm and 90.3%at 1200 nm),high coloration efficiency(114.9 cm^(2) C^(-1) at 633 nm and 420.3 cm^(2) C^(-1) at 1200 nm),quick switching time,excellent bistability,and good cycle stability(the transmittance modulation losses at 633 and 1200 nm were 11%and 3.5%respectively after 1000 cycles).A demonstrated DESW fabricated by the sol-gel film showed effective management of heat and light of sunlight.This study represents a significant advance in the preparation of dual-band electrochromic films,which will shed new light on advancing electrochromic technology for future energy-saving smart buildings. 展开更多
关键词 ELECTROCHROMISM tungsten oxide Smart windows Sol-gel method Dual-band absorption
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Preparation of Spherical Tungsten Particles Assisted by Hydrothermal Method
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作者 GUO Jiawang WEN Xiaoqiang +2 位作者 WU Ying XU Jianbing ZHOU Jieying 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2023年第6期1457-1462,共6页
We presented a strategy to prepare spherical tungsten powder by the combination of hydrothermal method and H2reduction process.In hydrothermal process,the micelle of tetraethylammonium bromide(TEAB)act as spherical te... We presented a strategy to prepare spherical tungsten powder by the combination of hydrothermal method and H2reduction process.In hydrothermal process,the micelle of tetraethylammonium bromide(TEAB)act as spherical templates for the deposition of tungsten oxide,whereas the excessive TEAB inhibit the formation of spherical tungsten oxide due to the dense molecular layer of TEAB on the tungsten oxide particles.Citric acid(CA)can control the formation rate and structure of the tungsten oxide when its concentration is more than 0.2 mol/L,because of its ability to coordinate with tungsten atoms.The synergistic effect of TEAB and CA facilitates the formation of spherical tungsten oxide with nanorod crown.After being treated by H_(2)at 600 and 650℃,the tungsten oxide particles are reduced to tungsten particles,which maintain the spherical structure of tungsten oxide and have porous structure. 展开更多
关键词 spherical tungsten particles spherical tungsten oxide hydrothermal method citric acid tetraethylammonium bromide
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Tungsten carbide-reduced graphene oxide intercalation compound as co-catalyst for methanol oxidation 被引量:3
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作者 施梅勤 章文天 +2 位作者 李影影 褚有群 马淳安 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2016年第11期1851-1859,共9页
Highly dispersed tungsten carbide(WC) nanoparticles(NPs) sandwiched between few-layer reduced graphene oxide(RGO) have been successfully synthesized by using thiourea as an anchoring and inducing reagent.The met... Highly dispersed tungsten carbide(WC) nanoparticles(NPs) sandwiched between few-layer reduced graphene oxide(RGO) have been successfully synthesized by using thiourea as an anchoring and inducing reagent.The metatungstate ion,[H2W(12)O(40)]^6-,is assembled on thiourea-modified graphene oxide(GO) by an impregnation method.The WC NPs,with a mean diameter of 1.5 nm,are obtained through a process whereby ammonium metatungstate first turns to WS2,which then forms an intercalation compound with RGO before growing,in situ,to WC NPs.The Pt/WC-RGO electrocatalysts are fabricated by a microwave-assisted method.The intimate contacts between Pt,WC,and RGO are confirmed by X-ray diffraction,scanning electron microscope,transmission electron microscope,and Raman spectroscopy.For methanol oxidation,the Pt/WC-RGO electrocatalyst exhibited an electrochemical surface area value of 246.1 m^2/g Pt and a peak current density of1364.7 mA/mg Pt,which are,respectively,3.66 and 4.77 times greater than those of commercial Pt/C electrocatalyst(67.2 m^2/g Pt,286.0 mA/mg Pt).The excellent CO-poisoning resistance and long-term stability of the electrocatalyst are also evidenced by CO stripping,chronoamperometry,and accelerated durability testing.Because Pt/WC-RGO has higher catalytic activity compared with that of commercial Pt/C,as a result of its intercalated structure and synergistic effect,less Pt will be required for the same performance,which in turn will reduce the cost of the fuel cell.The present method is facile,efficient,and scalable for mass production of the nanomaterials. 展开更多
关键词 tungsten carbide-reduced graphene oxide Intercalation compound THIOUREA ANCHORING Methanol oxidation
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Preparation of nano-sized tungsten carbide via fluidized bed 被引量:8
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作者 Feng Pan Zhan Du +4 位作者 Shaofu Li Jun Li Meiju Zhang Maoqiao Xiang Qingshan Zhu 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2020年第3期923-932,共10页
Ultrafine or nano-sized of tungsten carbide(WC)is the key material to prepare ultrafine grained cemented carbides.In this paper,nano-sized WC powders were directly prepared by using industrial nano-needle violet tungs... Ultrafine or nano-sized of tungsten carbide(WC)is the key material to prepare ultrafine grained cemented carbides.In this paper,nano-sized WC powders were directly prepared by using industrial nano-needle violet tungsten oxide(WO2.72)as the raw material,a fluidized bed as the reactor,and CO as the carbonization gas.The relationship between particle sizes and reaction temperatures,residence times,atmospheres has been investigated systematically.In addition,the physical–chemical indexes(such as residual oxygen,total carbon and free carbon)of the products were measured.The results indicated that the particle size of WC increased with the increase of temperature from 800 to 950°C.As the residence time increased,the particle size decreased gradually,and then increased due to slight sintering.The introduction of hydrogen reduced the carbonization rate,and is not beneficial to obtaining nano-sized WC.Products that satisfy the standard were obtained when WO2.72 reacted with CO at 850°C,900°C and 950°C for 3.0 h,2.5 h and 2.0 h,respectively.The particle sizes of the three samples calculated from the specific surface area were 46.4 nm,53.2 nm and 52.1 nm,respectively. 展开更多
关键词 NANOPARTICLES Violet tungsten oxide Nano tungsten carbide FLUIDIZED-BED Reduction-carbonization Process control
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Niobium Tungsten Oxide in a Green Water‑in‑Salt Electrolyte Enables Ultra‑Stable Aqueous Lithium‑Ion Capacitors 被引量:5
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作者 Shengyang Dong Yi Wang +2 位作者 Chenglong Chen Laifa Shen Xiaogang Zhang 《Nano-Micro Letters》 SCIE EI CAS CSCD 2020年第12期106-116,共11页
Aqueous hybrid supercapacitors are attracting increasing attention due to their potential low cost,high safety and eco-friendliness.However,the narrow operating potential window of aqueous electrolyte and the lack of ... Aqueous hybrid supercapacitors are attracting increasing attention due to their potential low cost,high safety and eco-friendliness.However,the narrow operating potential window of aqueous electrolyte and the lack of suitable negative electrode materials seriously hinder its future applications.Here,we explore high concentrated lithium acetate with high ionic conductivity of 65.5 mS cm−1 as a green“water-in-salt”electrolyte,providing wide voltage window up to 2.8 V.It facilitates the reversible function of niobium tungsten oxide,Nb18W16O93,that otherwise only operations in organic electrolytes previously.The Nb18W16O93 with lithium-ion intercalation pseudocapacitive behavior exhibits excellent rate performance,high areal capacity,and ultra-long cycling stability.An aqueous lithium-ion hybrid capacitor is developed by using Nb18W16O93 as negative electrode combined with graphene as positive electrode in lithium acetate-based“water-in-salt”electrolyte,delivering a high energy density of 41.9 W kg−1,high power density of 20,000 W kg−1 and unexceptionable stability of 50,000 cycles. 展开更多
关键词 Aqueous hybrid capacitors Water-in-salt electrolyte Niobium tungsten oxide Ultra-stability High power density
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Synthesis and electrical characterization of tungsten oxide nanowires 被引量:3
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作者 黄睿 朱静 于荣 《Chinese Physics B》 SCIE EI CAS CSCD 2009年第7期3024-3030,共7页
Tungsten oxide nanowires of diameters ranging from 7 to 200 nm are prepared on a tungsten rod substrate by using the chemical vapour deposition (CVD) method with vapour-solid (VS) mechanism.Tin powders are used to... Tungsten oxide nanowires of diameters ranging from 7 to 200 nm are prepared on a tungsten rod substrate by using the chemical vapour deposition (CVD) method with vapour-solid (VS) mechanism.Tin powders are used to control oxygen concentration in the furnace,thereby assisting the growth of the tungsten oxide nanowires.The grown tungsten oxide nanowires are determined to be of crystalline W18O49. I-V curves are measured by an in situ transmission electron microscope (TEM) to investigate the electrical properties of the nanowires.All of the I-V curves observed are symmetric,which reveals that the tungsten oxide nanowires are semiconducting. Quantitative analyses of the experimental I-V curves by using a metal semiconductor-metal (MSM) model give some intrinsic parameters of the tungsten oxide nanowires,such as the carrier concentration,the carrier mobility and the conductivity. 展开更多
关键词 tungsten oxide nanowires chemical vapour deposition (CVD) electrical characterization metal semiconductor metal (MSM) structure
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Aerobic oxidative desulfurization via magnetic mesoporous silica-supported tungsten oxide catalysts 被引量:1
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作者 Wei Jiang Xiang Gao +7 位作者 Lei Dong Jin Xiao Lin-Hua Zhu Guang-Ying Chen Su-Hang Xun Chong Peng Wen-Shuai Zhu Hua-Ming Li 《Petroleum Science》 SCIE CAS CSCD 2020年第5期1422-1431,共10页
It is usually difficult to remove dibenzothiophenes from diesel fuels by oxidation with molecular oxygen as an oxidant.In the study,tungsten oxide was supported on magnetic mesoporous silica by calcination to form a m... It is usually difficult to remove dibenzothiophenes from diesel fuels by oxidation with molecular oxygen as an oxidant.In the study,tungsten oxide was supported on magnetic mesoporous silica by calcination to form a magnetically separable catalyst for oxidative desulfurization of diesel fuel.By tuning different calcining temperatures,the catalyst calcined at 500℃showed a high catalytic activity with molecular oxygen as the oxidant.Under optimal reaction conditions,the sulfur removal of DBT reached 99.9%at 120℃after 8 h.Furthermore,the removals of 4-methyldibenzothiophene and 4,6-dimethyldibenzothiophene could also get up to 98.2%and 92.3%under the same conditions.The reaction mechanism was explored by selective quenching experiments and FT-IR spectra. 展开更多
关键词 Oxidative desulfurization Molecular oxygen Magnetic separation Mesoporous structure tungsten oxide
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Fabrication of oxygen-defective tungsten oxide nanorods for deep oxidative desulfurization of fuel 被引量:1
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作者 Haibin Sun Peiwen Wu +6 位作者 Jing He Mingyang Liu Linhua Zhu Fengxia Zhu Guangying Chen Minqiang He Wenshuai Zhu 《Petroleum Science》 SCIE CAS CSCD 2018年第4期849-856,共8页
Owing to the increasingly serious environmental issues caused by the sulfur burnt in fuel, desulfurization has become an important topic. In this work, an amphiphilic oxygen-defective tungsten oxide was synthesized by... Owing to the increasingly serious environmental issues caused by the sulfur burnt in fuel, desulfurization has become an important topic. In this work, an amphiphilic oxygen-defective tungsten oxide was synthesized by a colloidal chemistry method. The amphiphilic property and oxygen defects were well characterized, and the structure of the oxygen-defective tungsten oxide catalyst was investigated. In addition, the catalyst was employed in oxidative desulfurization system of fuel,and deep desulfurization was achieved. It was found that the very high oxidative desulfurization performance of oxygendefective tungsten oxide catalyst resulted from both the amphiphilic property and oxygen defects. This work can provide a strategy for preparation of highly active metal oxide catalysts with oxygen defects in oxidative desulfurization reaction of fuel. 展开更多
关键词 tungsten oxide Oxygen vacancies Oxidative desulfurization Amphiphilic catalyst
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Structures and optical properties of tungsten oxide thin films deposited by magnetron sputtering of WO_3 bulk:Effects of annealing temperatures 被引量:1
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作者 张锋 王海千 +3 位作者 王松 汪竟阳 钟志成 金叶 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第9期509-514,共6页
Tungsten oxide thin films were deposited on glass substrates by the magnetron sputtering of WO3 bulk at room temperature. The deposited films were annealed at different temperatures in air. The structural measurements... Tungsten oxide thin films were deposited on glass substrates by the magnetron sputtering of WO3 bulk at room temperature. The deposited films were annealed at different temperatures in air. The structural measurements indicate that the films annealed below 300℃ were amorphous, while the films annealed at 400 ℃ were mixed crystalline with hexagonal and triclinic phases of WO3. It was observed that the crystallization of the annealed films becomes more and more distinct with an increase in the annealing temperature. At 400 ℃, nanorod-like structures were observed on the film surface when the annealing time was increased from 60 min to 180 min. The presence of W=O stretching, W-O-W stretching, W-O-W bending and various lattice vibration modes were observed in Raman measurements. The optical absorption behaviors of the films in the range of 450-800 nm are very different with changing annealing temperatures from the room temperature to 400 ℃. After annealing at 400 ℃, the film becomes almost transparent. Increasing annealing time at 400 ℃ can lead to a small blue shift of the optical gap of the film. 展开更多
关键词 tungsten oxide film magnetron sputtering structure optical property
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Effect of iron valence on hydrothermal preparation of pyrochlore-type tungsten oxide
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作者 Qiu-sheng ZHOU Min XIANG +4 位作者 Dong LI Xiao-bin LI Tian-gui QI Zhi-hong PENG Gui-hua LIU 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2019年第5期1099-1106,共8页
Pyrochlore-type tungsten oxide (PTO), WO3·0.5H2O, is an emerging material with very wide potential applications. The influences of iron valences and the additive amount of ferrous ion on tungsten crystallization ... Pyrochlore-type tungsten oxide (PTO), WO3·0.5H2O, is an emerging material with very wide potential applications. The influences of iron valences and the additive amount of ferrous ion on tungsten crystallization ratio and the acceleration mechanism of ferrous ion were investigated when PTO was hydrothermally prepared in aqueous ammonium tungstate solution containing ammonium carbonate. The results show that ferrous ion can remarkably accelerate tungsten crystallization while both elemental iron and ferric ion have little influence on the crystallization. Moreover, the tungsten crystallization ratio increases with increasing the amount of ferrous ions added and reaches the maximum of about 60% with ferrous ion concentration of 16 g/L. FTIR analysis of the spent solution after PTO crystallization shows that ferrous ion can accelerate the conversion of WO4 tetrahedral to WO6 octahedron. Combined with XPS and XRD analyses of the hydrothermal product, the acceleration effect of ferrous ion on tungsten crystallization could basically be attributed to the increase in the interplanar spacing of PTO lattice caused by the incorporation of ferrous ion into PTO crystal lattice. The results presented is conducive to the efficient preparation of PTO powder and cleaner tungsten metallurgy. 展开更多
关键词 pyrochlore-type tungsten oxide ammonium tungstate solution ferrous ion CRYSTALLIZATION mechanism
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Morphology-controlled preparation of tungsten oxide nanostructures for gas-sensing application
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作者 秦玉香 刘长雨 柳杨 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第2期387-393,共7页
A novel three-dimensional(3D) hierarchical structure and a roughly oriented one-dimensional(1D) nanowire of WO3 are selectively prepared on an alumina substrate by an induced hydrothermal growth method.Each hierar... A novel three-dimensional(3D) hierarchical structure and a roughly oriented one-dimensional(1D) nanowire of WO3 are selectively prepared on an alumina substrate by an induced hydrothermal growth method.Each hierarchical structure is constructed hydrothermally through bilateral inductive growth of WO3 nanowire arrays from a nanosheet preformed on the substrate.Only roughly oriented 1D WO3 nanowire can be obtained from a spherical induction layer.The analyses show that as-prepared 1D nanowire and 3D hierarchical structures exhibit monoclinic and hexagonal phases of WO3,respectively.The gas-sensing properties of the nanowires and the hierarchical structure of WO_3,which include the variations of their resistances and response times when exposed to NO2,are investigated at temperatures ranging from room temperature(20 ℃) to 250 ℃ over 0.015 ppm-5 ppm NO2.The hierarchical WO3 behaves as a p-type semiconductor at room temperature,and shows p-to-n response characteristic reversal with the increase of temperature.Meanwhile,unlike the1 D nanowire,the hierarchical WO3 exhibits an excellent response characteristic and very good reversibility and selectivity to NO2 gas at room temperature due to its unique microstructure.Especially,it is found that the hierarchical VO3-based sensor is capable of detecting NO2 at a ppb level with ultrashort response time shorter than 5 s,indicating the potential of this material in developing a highly sensitive gas sensor with a low power consumption. 展开更多
关键词 tungsten oxide gas sensor hierarchical structure hydrothermal synthesis
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Lithium-ion diffusion path of tetragonal tungsten bronze(TTB)phase Nb_(18)W_(16)O_(93)
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作者 Chao SHEN Sai-nan JIANG +2 位作者 Cui-min DING Wei-shun XUE Ke-yu XIE 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2022年第11期3679-3686,共8页
By taking tetragonal tungsten bronze(TTB)phase Nb_(18)W_(16)O_(93)as an example,an improved solid-state sintering method at lower temperature of 1000℃for 36 h was proposed via applying nanoscale raw materials.XRD,SEM... By taking tetragonal tungsten bronze(TTB)phase Nb_(18)W_(16)O_(93)as an example,an improved solid-state sintering method at lower temperature of 1000℃for 36 h was proposed via applying nanoscale raw materials.XRD,SEM and XPS confirm that the expected sample was produced.GITT results show that the lithium-ion diffusion coefficient of Nb_(18)W_(16)O_(93)(10−12 cm^(2)/s)is higher than that of the conventional titanium-based anode,ensuring a relatively superior electrochemical performance.The lithium-ion diffusion mechanism was thoroughly revealed by using density functional theory simulation.There are three diffusion paths in TTB phase,among which the interlayer diffusion with the smallest diffusion barrier(0.46 eV)has more advantages than other typical anodes(such as graphite,0.56 eV).The relatively smaller lithium-ion diffusion barrier makes TTB phase Nb_(18)W_(16)O_(93)become a potential highspecific-power anode material. 展开更多
关键词 lithium-ion battery niobium tungsten oxide tetragonal tungsten bronze(TTB)phase lithium-ion diffusion mechanism diffusion path
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Tungsten oxide-anchored Ru clusters with electron-rich and anti-corrosive microenvironments for efficient and robust seawater splitting 被引量:2
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作者 Yiming Zhang Weiqiong Zheng +7 位作者 Huijuan Wu Ran Zhu Yinghan Wang Mao Wang Tian Ma Chong Cheng Zhiyuan Zeng Shuang Li 《SusMat》 SCIE EI 2024年第1期106-115,共10页
Ruthenium(Ru)has been recognized as a prospective candidate to substitute platinum catalysts in water-splitting-based hydrogen production.However,minimizing the Ru contents,optimizing the water dissociation energy of ... Ruthenium(Ru)has been recognized as a prospective candidate to substitute platinum catalysts in water-splitting-based hydrogen production.However,minimizing the Ru contents,optimizing the water dissociation energy of Ru sites,and enhancing the long-term stability are extremely required,but still face a great challenge.Here,we report on creating tungsten oxide-anchored Ru clusters(Ru-WO_(x))with electron-rich and anti-corrosive microenvironments for efficient and robust seawater splitting.Benefiting from the abundant oxygen vacancy structure in tungsten oxide support,the Ru-WO_(x)exhibits strong Ru-O and Ru-W bonds at the interface.Our study elucidates that the strong Ru-O bonds in Ru-WO_(x)may accelerate the water dissociation kinetics,and the Ru-W bonds will lead to the strong metal-support interaction and electrons transfer fromWto Ru.The optimal Ru-WO_(x)catalysts exhibit a low overpotential of 29 and 218mVat the current density of 10 mA cm^(−2) in alkaline and seawater media,respectively.The outstanding long-term stability discloses that the Ru-WO_(x)catalysts own efficient corrosion resistance in seawater electrolysis.We believe that thiswork offers new insights into the essential roles of electron-rich and anti-corrosivemicroenvironments in Ru-based catalysts and provide a new pathway to design efficient and robust cathodes for seawater splitting. 展开更多
关键词 hydrogen production microenvironment modulation noble metal catalysts seawater splitting tungsten oxide
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New Superionic Memory Devices Can Provide Clues to the Human Memory Structure and to Consciousness
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作者 Hans Hermann Otto 《Journal of Applied Mathematics and Physics》 2023年第2期377-376,共10页
Since the work of Penrose and Hameroff the possibility is discussed that the location of human memory and consciousness could be connected with tubulin microtubules. If one would use superionic nano-materials rolled u... Since the work of Penrose and Hameroff the possibility is discussed that the location of human memory and consciousness could be connected with tubulin microtubules. If one would use superionic nano-materials rolled up to microtubules with an electrolyte inside the formed channels mediating fast ionic exchange of protons respectively lithium ions, it seems to be possible to write into such materials whole image arrays (pictures) under the action of the complex electromagnetic spectrum that composes these images. The same material and architecture may be recommended for super-computers. Especially microtubules with a protofilament number of 13 are the most important to note. We connected such microtubules before with Fibonacci nets composed of 13 sub-cells that were helically rolled up to deliver suitable channels. Our recent Fibonacci analysis of Wadsley-Roth shear phases such as niobium tungsten oxide , exhibiting channels for ultra-fast lithium-ion diffusion, suggests to use these materials, besides super-battery main application, in form of nanorods or microtubules as effectively working superionic memory devices for computers that work ultra-fast with the complex effectiveness of human brains. Finally, we pose the question, whether dark matter, ever connected with ultrafast movement of ordinary matter, may be responsible for synchronization between interactions of human brains and consciousness. 展开更多
关键词 Memory Device Niobium tungsten Oxide Crystallographic Shear Lithium Intercalation Superionicity Super Battery Fibonacci Nets Fibonacci Stoichiometry Tubulin Microtubules
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