C_(3)N_(4),C_(3)N_(4)@Ti_(3)C_(2)and W_(18)O_(49)@C_(3)N_(4)@Ti_(3)C_(2)hollow spheres were successfully prepared by using SiO_(2)template followed by gradual deposition method.The degradation of phenol solution and p...C_(3)N_(4),C_(3)N_(4)@Ti_(3)C_(2)and W_(18)O_(49)@C_(3)N_(4)@Ti_(3)C_(2)hollow spheres were successfully prepared by using SiO_(2)template followed by gradual deposition method.The degradation of phenol solution and photolysis ability were tested to characterize its photocatalytic activity.Compared with the single-shelled C_(3)N_(4)and C_(3)N_(4)@Ti_(3)C_(2)hollow spheres,double-shelled W_(18)O_(49)@C_(3)N_(4)@Ti_(3)C_(2)hollow spheres possessed larger surface area and fast charge separation efficiency,exhibiting about 8.9 times and 4.0 times higher H_(2)evolution than those of C_(3)N_(4),C_(3)N_(4)@Ti_(3)C_(2)hollow spheres,respectively.The photocatalytic mechanism of the W_(18)O_(49)@C_(3)N_(4)@Ti_(3)C_(2)hollow spheres were carefully investigated according to the results of morphology design and photoelectric performance.A Z scheme mechanism based on the construction of heterojunctions was proposed to explain the improvement of photocatalytic performance.This new charge transfer mechanism appears to greatly inhibit the recombination of electrons/holes during the charge transfer process,while maintaining its strong hydrogen reduction ability,resulting in a higher photocatalytic performance.展开更多
The electrochemical conversion is closely correlated with the electrocatalytic activities of the electrocatalyst.Herein,the urchin-like Ni-doped W_(18)O_(49)/NF with enriched active sites was prepared by solvothermal ...The electrochemical conversion is closely correlated with the electrocatalytic activities of the electrocatalyst.Herein,the urchin-like Ni-doped W_(18)O_(49)/NF with enriched active sites was prepared by solvothermal method followed by a low-temperature pyrolysis treatment was reported.Results demonstrate that the incorporation of Ni-doping triggers the lattice distortion of W_(18)O_(49) for the increasement of oxygen defects.Further,high-valent W^(6+)are partially reduced to low-valent W^(4+),wherein the electrons originate from the oxidation process of Ni^(2+)to Ni^(3+).The Ni^(3+)ions show an enhanced orbital overlap with the OER reaction intermediates.The generated W^(4+)ions contribute to release oxygen vacancies,eventually reorganizing Ni-doped W_(18)O_(49)/NF to unique electrochemical active species with a special amorphous-crystalline interface(AM/NiWO_x/NiOOH/NF).Simultaneously,the reconstruction results in an optimized valence band and conduction band.Eventually,the resultant AM/NiWO_x/NiOOH/NF with abundant active sites and improved oxidation/reduction capability exhibits more superior catalytic performance compared with the Ni-doped W_(18)O_(49)/NF counterpart.This study gives more insights in the electrochemical evolution of the tungsten-based oxide and provides effective strategies for optimizing the catalytic activity of materials with inherent hydrogen evolution reaction limitations.展开更多
Non-noble transition metal oxides(TMOs)are promising catalysts with improved catalytic activity and stability in oxygen evolution reaction(OER).However,the structural complexity of TMO-based electrocatalysts renders t...Non-noble transition metal oxides(TMOs)are promising catalysts with improved catalytic activity and stability in oxygen evolution reaction(OER).However,the structural complexity of TMO-based electrocatalysts renders the determination of the active sites and OER mechanisms challenging.Here,we demonstrate that the OER activity of Co-doped one-dimensional W_(18)O_(49)(Co-W_(18)O_(49))is intrinsically dominated by the surface structure and electronic properties of the octahedral sites and Co-O-W bonds.Compared with RuO_(2) and W_(18)O_(49) heterogeneous electrocatalysts,Co-W_(18)O_(49) exhibits higher turnover frequency,attaining 1.97 s−1 at 500 mV overpotential.The results indicate that Co substitution contributes to the localized charge distribution of the active octahedral sites constructed by the Co-O-W bonds under OER conditions.Here,we determine the mechanism of TMOs for the OER,which may be applied to various other TMOs for OER electrocatalyst design.展开更多
W_(18)O_(49)nanowires(W_(18)O_(49)NWs)with unique one-dimension structures and excellent electron/ions transport properties have attracted increasing attention in academia and industry because of their potential appli...W_(18)O_(49)nanowires(W_(18)O_(49)NWs)with unique one-dimension structures and excellent electron/ions transport properties have attracted increasing attention in academia and industry because of their potential applications in many energy-related devices.In the past decades,many research articles related to W_(18)O_(49)have been published,but there are insufficient review articles focusing on W_(18)O_(49)NWs.In this review,we present the crystal structure of W_(18)O_(49)and briefly introduce the synthesis methods and growth mechanism of W_(18)O_(49)NWs.Moreover,their applications in energy conversion and storage devices are summarized.Finally,the current challenges and opportunities for applying W_(18)O_(49)NWs are provided.We hope this review can promote the development of W_(18)O_(49)NWs in energy conversion,storage,and other promising applications.展开更多
基金Supported by the National Natural Science Foundation of China(Nos.91963207 and 12075174)。
文摘C_(3)N_(4),C_(3)N_(4)@Ti_(3)C_(2)and W_(18)O_(49)@C_(3)N_(4)@Ti_(3)C_(2)hollow spheres were successfully prepared by using SiO_(2)template followed by gradual deposition method.The degradation of phenol solution and photolysis ability were tested to characterize its photocatalytic activity.Compared with the single-shelled C_(3)N_(4)and C_(3)N_(4)@Ti_(3)C_(2)hollow spheres,double-shelled W_(18)O_(49)@C_(3)N_(4)@Ti_(3)C_(2)hollow spheres possessed larger surface area and fast charge separation efficiency,exhibiting about 8.9 times and 4.0 times higher H_(2)evolution than those of C_(3)N_(4),C_(3)N_(4)@Ti_(3)C_(2)hollow spheres,respectively.The photocatalytic mechanism of the W_(18)O_(49)@C_(3)N_(4)@Ti_(3)C_(2)hollow spheres were carefully investigated according to the results of morphology design and photoelectric performance.A Z scheme mechanism based on the construction of heterojunctions was proposed to explain the improvement of photocatalytic performance.This new charge transfer mechanism appears to greatly inhibit the recombination of electrons/holes during the charge transfer process,while maintaining its strong hydrogen reduction ability,resulting in a higher photocatalytic performance.
基金supported by the National Natural Science Foundation of China (52073166)the China Scholarship Council (CSC) for the Research Training Program of Guojuan Hai to study at University of Wollongong(201908610223)+5 种基金the Xi’an Key Laboratory of Green Manufacture of Ceramic Materials Foundation (2019220214SYS017CG039)the Key Program for International S&T Cooperation Projects of Shaanxi Province(2020KW-038, 2020GHJD-04)the Science and Technology Program of Xi’an,China (2020KJRC0009)the Scientific Research Program Funded by Shaanxi Provincial Education Department(No. 20JY001)Science and Technology Resource Sharing Platform of Shaanxi Province (2020PT-022)Science and Technology Plan of Weiyang District,Xi’an (202009)。
文摘The electrochemical conversion is closely correlated with the electrocatalytic activities of the electrocatalyst.Herein,the urchin-like Ni-doped W_(18)O_(49)/NF with enriched active sites was prepared by solvothermal method followed by a low-temperature pyrolysis treatment was reported.Results demonstrate that the incorporation of Ni-doping triggers the lattice distortion of W_(18)O_(49) for the increasement of oxygen defects.Further,high-valent W^(6+)are partially reduced to low-valent W^(4+),wherein the electrons originate from the oxidation process of Ni^(2+)to Ni^(3+).The Ni^(3+)ions show an enhanced orbital overlap with the OER reaction intermediates.The generated W^(4+)ions contribute to release oxygen vacancies,eventually reorganizing Ni-doped W_(18)O_(49)/NF to unique electrochemical active species with a special amorphous-crystalline interface(AM/NiWO_x/NiOOH/NF).Simultaneously,the reconstruction results in an optimized valence band and conduction band.Eventually,the resultant AM/NiWO_x/NiOOH/NF with abundant active sites and improved oxidation/reduction capability exhibits more superior catalytic performance compared with the Ni-doped W_(18)O_(49)/NF counterpart.This study gives more insights in the electrochemical evolution of the tungsten-based oxide and provides effective strategies for optimizing the catalytic activity of materials with inherent hydrogen evolution reaction limitations.
基金support from the Natural Science Foundation of China as a general project(Grant Nos.21874099,22006029,22076082,and 22176140)Frontiers Science Center for New Organic Matter(Grant No.63181206)the Tianjin Commission of Science and Technology as a Key Technology Research and Develop-ment project(Grant Nos.19YFZCSF00740 and 20YFZCSN01070).
文摘Non-noble transition metal oxides(TMOs)are promising catalysts with improved catalytic activity and stability in oxygen evolution reaction(OER).However,the structural complexity of TMO-based electrocatalysts renders the determination of the active sites and OER mechanisms challenging.Here,we demonstrate that the OER activity of Co-doped one-dimensional W_(18)O_(49)(Co-W_(18)O_(49))is intrinsically dominated by the surface structure and electronic properties of the octahedral sites and Co-O-W bonds.Compared with RuO_(2) and W_(18)O_(49) heterogeneous electrocatalysts,Co-W_(18)O_(49) exhibits higher turnover frequency,attaining 1.97 s−1 at 500 mV overpotential.The results indicate that Co substitution contributes to the localized charge distribution of the active octahedral sites constructed by the Co-O-W bonds under OER conditions.Here,we determine the mechanism of TMOs for the OER,which may be applied to various other TMOs for OER electrocatalyst design.
基金Financial support from the National Natural Science Foundation(No.22075151)of Chinathe Natural Science Foundation of Jiangxi(No.20161BBE50095)the project of Jiangxi Academy of Sciences(No.2022YSBG21019 and No.2023YJC2018)is gratefully acknowledged。
文摘W_(18)O_(49)nanowires(W_(18)O_(49)NWs)with unique one-dimension structures and excellent electron/ions transport properties have attracted increasing attention in academia and industry because of their potential applications in many energy-related devices.In the past decades,many research articles related to W_(18)O_(49)have been published,but there are insufficient review articles focusing on W_(18)O_(49)NWs.In this review,we present the crystal structure of W_(18)O_(49)and briefly introduce the synthesis methods and growth mechanism of W_(18)O_(49)NWs.Moreover,their applications in energy conversion and storage devices are summarized.Finally,the current challenges and opportunities for applying W_(18)O_(49)NWs are provided.We hope this review can promote the development of W_(18)O_(49)NWs in energy conversion,storage,and other promising applications.
