The photochemical conversion of plastic waste into valuable resources under ambient conditions is challenging.Achieving efficient photocatalytic conversion necessitates intimate contact between the photocatalyst and p...The photochemical conversion of plastic waste into valuable resources under ambient conditions is challenging.Achieving efficient photocatalytic conversion necessitates intimate contact between the photocatalyst and plastic substrate,as water molecules are readily oxidized by photogenerated holes,potentially bypassing the plastic as the electron donor.This study demonstrated a novel strategy for depositing polystyrene(PS)waste onto a photoanode by leveraging its solubility in specific organic solvents,including acetone and chloroform,thus enhancing the interface contact.We used an anodization technique to fabricate a skeleton-like porous tungsten oxide(WO_(3))structure,which exhibited higher durability against detachment from a conductive substrate than the WO_(3) photoanode fabricated using the doctor blade method.Upon illumination,the photogenerated holes were transferred from WO_(3) to PS,promoting the oxidative degradation of plastic waste under ambient conditions.Consequently,the oxidative degradation of PS on the anode side generated carbon dioxide,while the cathodic process produced hydrogen gas through water reduction.Our findings pave the way for sunlight-driven plastic waste treatment technologies that concurrently generate valuable fuels or chemicals and offer the dual benefits of cost savings and environmental protection.展开更多
Wearable sensors are pivotal for point-of-care diagnostics,yet their application in extreme conditions is rarely conducted.In this work,we present a wearable pH sensor using tungsten oxide aerogel(TOA)as the sensing m...Wearable sensors are pivotal for point-of-care diagnostics,yet their application in extreme conditions is rarely conducted.In this work,we present a wearable pH sensor using tungsten oxide aerogel(TOA)as the sensing material.With the advantages of large specific surface area,high porosity and interconnected network structures,TOA not only provides excellent pH sensing performance but also demonstrates remarkable structural and sensing stability.The potentiometric pH sensor exhibits a high sensitivity(−63.70 mV/pH),a low detectable limit(0.05)and a superior stability(maintained over 50,000 s).Integrated with a Bluetooth module,the wearable sensor achieves non-invasive and real-time pH monitoring on the human skin with minimal deviation(1.91%)compared to the commercial pH meter.More importantly,the anti-impact behaviors of the TOA-based sensing materials and chip,along with the pH wearable sensor on a pig exhibit an outstanding shock-resistance ability,with variations no more than 7.17%under an impact of 118.38 kPa.Therefore,this study shows great promise for the aerogel-based personalized health management in the extreme environment.展开更多
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
In this work,tungsten oxide with different concentrations(0,0.4 at%,2.0 at%and 3.2 at%)was introduced to the ceria nanorods via a deposition-precipitation(DP)approach,and copper species of ca.10 at%were sequentially a...In this work,tungsten oxide with different concentrations(0,0.4 at%,2.0 at%and 3.2 at%)was introduced to the ceria nanorods via a deposition-precipitation(DP)approach,and copper species of ca.10 at%were sequentially anchored onto the modified ceria support by a similar DP route.The aim of the study was to investigate the effect of the amount of tungsten oxide(0,0.4 at%,2.0 at%,and 3.2 at%)modifier on the copper-ceria catalysts for CO oxidation reaction and shed light on the structure-activity relationship.By the aids of multiple characterization techniques including N2 adsorption,high-resolution transmission electron microscopy(HRTEM),powder X-ray diffraction(XRD),X-ray absorption fine structure(XAFS),and temperature-programmed reduction by hydrogen(H2-TPR)in combination with the catalytic performance for CO oxidation reaction,it is found that the copper-ceria samples maintain the crystal structure of the fluorite fcc CeO2 phase with the same nanorod-like morphology with the introduction of tungsten oxide,while the textural properties(the surface area,pore volume and pore size)of ceria support and copper-ceria catalysts are changed,and the oxidation states of copper and tungsten are kept the same as Cu2+and W6+before and after the reaction,but the introduction of tungsten oxide(WO3)significantly changes the metal-support interaction(transfer the CuOx clusters to Cu-[Ox]-Ce species),which delivers to impair the catalytic activity of copper-ceria catalysts for CO oxidation reaction.展开更多
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
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
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
Although converting the greenhouse gasses carbon dioxide(CO_(2))into solar fuels is regarded as a convenient means of solar energy storage,the intrinsic mechanism on how the high chemical inertness linear CO_(2)molecu...Although converting the greenhouse gasses carbon dioxide(CO_(2))into solar fuels is regarded as a convenient means of solar energy storage,the intrinsic mechanism on how the high chemical inertness linear CO_(2)molecules is activated and converted on a semiconductor oxide is still elusive.Herein,by creating the oxygen vacancies on the typical hexagonal tungsten oxide(WO3),we realize the continuous photoinduced CO_(2)reduction to selectively produce CO under light irradiation,which was verified by isotope labeling experiment.Detailed oxygen vacancies evolution investigation indicates that light irradiation can simultaneously induce the in-situ formation of oxygen vacancies on hexagonal WO3,and the oxygen vacancies promote the adsorption and activation of CO_(2)molecules,leading to the CO_(2)reduction to CO on the hexagonal WO3via an oxygen vacancies-involved process.Besides,the existence of water further promotes the formation of CO_(2)reduction intermediate,further promote the CO_(2)photoreduction.Our work provides insight on the mechanism for converting CO_(2)into CO under light irradiation.展开更多
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
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
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
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
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
Electrocatalysis plays a crucial role in the field of clean energy conversion and provides essential support for the development of eco-friendly technology. There is a pressing need for electrocatalysts in renewable e...Electrocatalysis plays a crucial role in the field of clean energy conversion and provides essential support for the development of eco-friendly technology. There is a pressing need for electrocatalysts in renewable energy systems that exhibit exceptional activity, selectivity, stability, and economic viability. The utilization of metal oxides as electrocatalysts for the process of water splitting has made substantial progress in both theoretical and practical aspects and has emerged as a widely explored field of research. Tungsten oxides(WO_(x)) have attracted much attention and are regarded as a highly promising electrocatalytic material due to their exceptional electrocatalytic activity, cost-effectiveness, and ability to withstand extreme conditions. This review introduces the fundamental mechanism of WOx-based electrocatalysts for the hydrogen evolution reaction and the oxygen evolution reaction, providing a comprehensive overview of recent research advancements in their modification. Factors contributing to the catalytic activity and stability of WOxare explored, highlighting their potential for industrial applications. The aim herein is to provide guidelines for the design and fabrication of WOx-based electrocatalysts, thereby facilitating further research on their mechanistic properties and stability improvements in water splitting.展开更多
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
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
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
As an important powder material for scandate cathode,Sc_(2) O_(3)-doped WO_(3) powder together with hollow spherical WO_(3) for comparison was prepared by spraydrying method.The reduction behavior and kinetics of pure...As an important powder material for scandate cathode,Sc_(2) O_(3)-doped WO_(3) powder together with hollow spherical WO_(3) for comparison was prepared by spraydrying method.The reduction behavior and kinetics of pure WO_(3) and Sc_(2) O_(3)-doped WO_(3) were studied by temperatureprogrammed reduction(TPR) method.It is found that scandia doping can decrease the reduction activation energy of WO_(3) and thus lower the reduction temperature and increase the reduction rate.Based on the kinetics results,the reduction techniques are presented.The obtained powder has a narrow size distribution in the range of 0.6-0.8 μm.展开更多
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
Graphene and its derivatives are the hot topics of research during this decade due to their excellent thermal conductivities,mechanical strength,current densities,electron motilities,and large surface area.This review...Graphene and its derivatives are the hot topics of research during this decade due to their excellent thermal conductivities,mechanical strength,current densities,electron motilities,and large surface area.This review article explores the outstanding applicability and features of graphene derivatives.The transition metal oxides(TMOs)have also gained considerable research attention due to their unique physicochemical properties in photocatalytic,self-cleaning,and gas sensing applications.Among TMOs,tungsten metal oxides have received a tremendous response as they are naturally abundant,low in cost,less toxic,environmental friendly,and can be manufactured using various physical and chemical methods.It exhibits a cubic perovskite-like structure based on the corner-sharing of regular octahedra with the oxygen atoms at the corner and the tungsten atoms at the centre of each octahedron.It also shows structural polymorphism and sub stoichiometric phase transitions,which attracted the attention of researchers over the past few years to explore their potential in various applications.Pairing graphene and its derivatives with tungsten oxide(WO_(3))to create heterojunction could be an auspicious tool to improve photocatalysis,energy storage,medical,electrochromism,and energy efficiency conversion.In addition,composite exhibits significantly higher efficiency than either individual material due to their well-matched band edge positions,efficient charge separation,and light-harvesting abilities.The morphology and heterojunction were found to be quite beneficial in improving the overall performance of the composite.In this review article,the noteworthy endeavors and turning points are accomplished utilizing heterojunction between WO_(3)and graphene derivatives for different applications.This review article will also provide the research gap and excite new ideas for further improvement of graphene-based tungsten oxide nanocomposites.Conclusively,the scope of future research work to design the ternary composite with high efficiency utilizing WO_(3)and graphene is also explored.展开更多
基金supported by the National Research Foundation of Korea(NRF)funded by the Ministry of Science and Information and Communication Technology(ICT)(NRF-2020M3H4A3106354)Korea Government(MSIT,RS-2023-00213022)the Korea Institution of Science and Technology(KIST)internal projects.
文摘The photochemical conversion of plastic waste into valuable resources under ambient conditions is challenging.Achieving efficient photocatalytic conversion necessitates intimate contact between the photocatalyst and plastic substrate,as water molecules are readily oxidized by photogenerated holes,potentially bypassing the plastic as the electron donor.This study demonstrated a novel strategy for depositing polystyrene(PS)waste onto a photoanode by leveraging its solubility in specific organic solvents,including acetone and chloroform,thus enhancing the interface contact.We used an anodization technique to fabricate a skeleton-like porous tungsten oxide(WO_(3))structure,which exhibited higher durability against detachment from a conductive substrate than the WO_(3) photoanode fabricated using the doctor blade method.Upon illumination,the photogenerated holes were transferred from WO_(3) to PS,promoting the oxidative degradation of plastic waste under ambient conditions.Consequently,the oxidative degradation of PS on the anode side generated carbon dioxide,while the cathodic process produced hydrogen gas through water reduction.Our findings pave the way for sunlight-driven plastic waste treatment technologies that concurrently generate valuable fuels or chemicals and offer the dual benefits of cost savings and environmental protection.
基金supported by the National Natural Science Foundation of China(Nos.22374119 and 22274127)the Research Fund of the State Key Laboratory of Solidification Processing(NPU),China(No.2021-QZ-01)+1 种基金the Key Project of Natural Science Fund of Shaanxi Province(Nos.2023-JC-ZD-06 and 2024JC-YBQN-0636)the Open Project of the State Key Laboratory of Transducer Technology(No.SKT2307).
文摘Wearable sensors are pivotal for point-of-care diagnostics,yet their application in extreme conditions is rarely conducted.In this work,we present a wearable pH sensor using tungsten oxide aerogel(TOA)as the sensing material.With the advantages of large specific surface area,high porosity and interconnected network structures,TOA not only provides excellent pH sensing performance but also demonstrates remarkable structural and sensing stability.The potentiometric pH sensor exhibits a high sensitivity(−63.70 mV/pH),a low detectable limit(0.05)and a superior stability(maintained over 50,000 s).Integrated with a Bluetooth module,the wearable sensor achieves non-invasive and real-time pH monitoring on the human skin with minimal deviation(1.91%)compared to the commercial pH meter.More importantly,the anti-impact behaviors of the TOA-based sensing materials and chip,along with the pH wearable sensor on a pig exhibit an outstanding shock-resistance ability,with variations no more than 7.17%under an impact of 118.38 kPa.Therefore,this study shows great promise for the aerogel-based personalized health management in the extreme environment.
基金supported by the National Natural Science Foundation of China(51902064)the Natural Science Foundation of Guangxi(2022GXNSFFA0350325)+2 种基金the Scientific and Technological Bases and Talents of Guangxi(Guike AD20159073)the special fund for“Guangxi Bagui Scholars”the“Guangxi HundredTalent Program”。
文摘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.
基金Project supported by National Natural Science Foundation of China(21773288,51902093)National Key Basic Research Program of China(2017YFA0403402)。
文摘In this work,tungsten oxide with different concentrations(0,0.4 at%,2.0 at%and 3.2 at%)was introduced to the ceria nanorods via a deposition-precipitation(DP)approach,and copper species of ca.10 at%were sequentially anchored onto the modified ceria support by a similar DP route.The aim of the study was to investigate the effect of the amount of tungsten oxide(0,0.4 at%,2.0 at%,and 3.2 at%)modifier on the copper-ceria catalysts for CO oxidation reaction and shed light on the structure-activity relationship.By the aids of multiple characterization techniques including N2 adsorption,high-resolution transmission electron microscopy(HRTEM),powder X-ray diffraction(XRD),X-ray absorption fine structure(XAFS),and temperature-programmed reduction by hydrogen(H2-TPR)in combination with the catalytic performance for CO oxidation reaction,it is found that the copper-ceria samples maintain the crystal structure of the fluorite fcc CeO2 phase with the same nanorod-like morphology with the introduction of tungsten oxide,while the textural properties(the surface area,pore volume and pore size)of ceria support and copper-ceria catalysts are changed,and the oxidation states of copper and tungsten are kept the same as Cu2+and W6+before and after the reaction,but the introduction of tungsten oxide(WO3)significantly changes the metal-support interaction(transfer the CuOx clusters to Cu-[Ox]-Ce species),which delivers to impair the catalytic activity of copper-ceria catalysts for CO oxidation reaction.
基金Shengyang Dong and Yi Wang contributed equally to this work.This work was supported by the National Natural Science Foundation of China(Nos.U1802256,51672128,51802154)the Key Research and Development Program in Jiangsu Province(BE2018122)+1 种基金Jiangsu Specially-Appointed Professors Program,the Fundamental Research Funds for the Central Universities(NE2016005)the Startup Foundation for Introducing Talent of NUIST(1441622001004).
文摘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.
基金Project supported by the National Natural Science Foundation of China (Grant No 50671053)
文摘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.
基金financially supported by the National Natural Science Foundation of China(Nos.21978119,21576122,and 21766007)a Project Funded by the Priority Academic Program Development of Jiangsu Higher Education Institutionsthe support of the Jiangsu Government Scholarship for oversea studies。
文摘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.
基金supported by National Natural Science Foundation of China(No.22088102)supported by National Natural Science Foundation of China(No.22090033)+1 种基金the support from Youth Innovation Promotion Association of Chinese Academy of SciencesDalian Institute of Chemical Physics,CAS。
文摘Although converting the greenhouse gasses carbon dioxide(CO_(2))into solar fuels is regarded as a convenient means of solar energy storage,the intrinsic mechanism on how the high chemical inertness linear CO_(2)molecules is activated and converted on a semiconductor oxide is still elusive.Herein,by creating the oxygen vacancies on the typical hexagonal tungsten oxide(WO3),we realize the continuous photoinduced CO_(2)reduction to selectively produce CO under light irradiation,which was verified by isotope labeling experiment.Detailed oxygen vacancies evolution investigation indicates that light irradiation can simultaneously induce the in-situ formation of oxygen vacancies on hexagonal WO3,and the oxygen vacancies promote the adsorption and activation of CO_(2)molecules,leading to the CO_(2)reduction to CO on the hexagonal WO3via an oxygen vacancies-involved process.Besides,the existence of water further promotes the formation of CO_(2)reduction intermediate,further promote the CO_(2)photoreduction.Our work provides insight on the mechanism for converting CO_(2)into CO under light irradiation.
基金financial support by Students’ Platform for innovation and entrepreneurship training of Jiangsu Province (201810299008z)the National Nature Science Foundation of China (Nos. 21576122, 21722604, 21766007)+1 种基金Key Laboratory of Tropical Medicinal Plant Chemistry of Ministry of Education, Hainan Normal University (20150376)the Natural Science Foundation of Jiangsu Provincial Department of Education (17KJA150002)
文摘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.
基金supported by the Young Scientists Fund of the National Natural Science Foundation of China(Grant Nos.11104365 and 11104366)the Hubei Key Laboratory of Low Dimensional Optoelectronic Material and Devices,China(Grant No.13XKL02002)
文摘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.
文摘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.
文摘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.
基金Project(51274243) supported by the National Natural Science Foundation of China
文摘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.
基金supported by the National Natural Science Foundation of China (grant no. 51902292)the China Postdoctoral Science Foundation (grant no. 2024M752942)the Project funding for Young Backbone Teachers in Colleges and Universities of Henan Province (2020GGJS013)。
文摘Electrocatalysis plays a crucial role in the field of clean energy conversion and provides essential support for the development of eco-friendly technology. There is a pressing need for electrocatalysts in renewable energy systems that exhibit exceptional activity, selectivity, stability, and economic viability. The utilization of metal oxides as electrocatalysts for the process of water splitting has made substantial progress in both theoretical and practical aspects and has emerged as a widely explored field of research. Tungsten oxides(WO_(x)) have attracted much attention and are regarded as a highly promising electrocatalytic material due to their exceptional electrocatalytic activity, cost-effectiveness, and ability to withstand extreme conditions. This review introduces the fundamental mechanism of WOx-based electrocatalysts for the hydrogen evolution reaction and the oxygen evolution reaction, providing a comprehensive overview of recent research advancements in their modification. Factors contributing to the catalytic activity and stability of WOxare explored, highlighting their potential for industrial applications. The aim herein is to provide guidelines for the design and fabrication of WOx-based electrocatalysts, thereby facilitating further research on their mechanistic properties and stability improvements in water splitting.
基金Project supported by the National Natural Science Foundation of China (Grant Nos. U0634002,50725206 and 50672135)the National Basic Research Program of China (Grant Nos. 2003CB314701,2007CB935501 and 2008AA03A314)the Department of Information Industry of Guangdong Province,China
文摘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.
基金supported by the National Natural Science Foundation of China(Nos.22125501,U22A20152,22105043,52225204,52173233)Key Basic Research Program of Science and Technology Commission of Shanghai Municipality(No.20JC1415300)+1 种基金the state key laboratory of Transducer Technology of China(No.SKT2207)the Fundamental Research Funds for the Central Universities(No.20720220010)。
文摘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.
基金supported by the National Natural Science Foundation of China(Grant Nos.61274074 and 61271070)the Natural Science Foundation of Tianjin,China(Grant No.11JCZDJC15300)
文摘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.
基金financially supported by the National Key Research and Development Program of China(Nos.2017YFA0701000 and 2016YFE0126900)the National Natural Science Foundation of China(Nos.51471006,51534009 and52621003)the Fundamental Research Funds for the Central Universities(Nos.ZYGX2018J024 and ZYGX2015Z010)。
文摘As an important powder material for scandate cathode,Sc_(2) O_(3)-doped WO_(3) powder together with hollow spherical WO_(3) for comparison was prepared by spraydrying method.The reduction behavior and kinetics of pure WO_(3) and Sc_(2) O_(3)-doped WO_(3) were studied by temperatureprogrammed reduction(TPR) method.It is found that scandia doping can decrease the reduction activation energy of WO_(3) and thus lower the reduction temperature and increase the reduction rate.Based on the kinetics results,the reduction techniques are presented.The obtained powder has a narrow size distribution in the range of 0.6-0.8 μm.
基金supported by the International Science & Technology Cooperation Program of China(2010DFB63680)the National Natural Science Foundation of China(21376220)Zhejiang Provincial Natural Science Foundation of China(LY16B060009,LY12B03008)~~
文摘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.
基金partially supported by The Institute of Science,Dr.Homi Bhabha State University,15,Madam Cama Road,Mumbai-400032,MH,India。
文摘Graphene and its derivatives are the hot topics of research during this decade due to their excellent thermal conductivities,mechanical strength,current densities,electron motilities,and large surface area.This review article explores the outstanding applicability and features of graphene derivatives.The transition metal oxides(TMOs)have also gained considerable research attention due to their unique physicochemical properties in photocatalytic,self-cleaning,and gas sensing applications.Among TMOs,tungsten metal oxides have received a tremendous response as they are naturally abundant,low in cost,less toxic,environmental friendly,and can be manufactured using various physical and chemical methods.It exhibits a cubic perovskite-like structure based on the corner-sharing of regular octahedra with the oxygen atoms at the corner and the tungsten atoms at the centre of each octahedron.It also shows structural polymorphism and sub stoichiometric phase transitions,which attracted the attention of researchers over the past few years to explore their potential in various applications.Pairing graphene and its derivatives with tungsten oxide(WO_(3))to create heterojunction could be an auspicious tool to improve photocatalysis,energy storage,medical,electrochromism,and energy efficiency conversion.In addition,composite exhibits significantly higher efficiency than either individual material due to their well-matched band edge positions,efficient charge separation,and light-harvesting abilities.The morphology and heterojunction were found to be quite beneficial in improving the overall performance of the composite.In this review article,the noteworthy endeavors and turning points are accomplished utilizing heterojunction between WO_(3)and graphene derivatives for different applications.This review article will also provide the research gap and excite new ideas for further improvement of graphene-based tungsten oxide nanocomposites.Conclusively,the scope of future research work to design the ternary composite with high efficiency utilizing WO_(3)and graphene is also explored.
