Reducing the production costs of clean energy carriers such as hydrogen through scalable water electrolysis is a potential solution for advancing the hydrogen economy.Among the various material candidates,our group de...Reducing the production costs of clean energy carriers such as hydrogen through scalable water electrolysis is a potential solution for advancing the hydrogen economy.Among the various material candidates,our group demonstrated transition-metal-based materials with tunable electronic characteristics,various phases,and earth-abundance.Herein,electrochemical water oxidation using Cu_(2)Se-V_(2)O_(5) as a non-precious metallic electrocatalyst via a hydrothermal approach is reported.The water-splitting performance of all the fabricated electrocatalysts was evaluated after direct growth on a stainless-steel substrate.The electrochemically tuned Cu_(2)Se-V_(2)O_(5) catalyst exhibited a reduced overpotential of 128 mV and provided a reduced Tafel slope of 57 mV·dec^(−1) to meet the maximum current density of 250 mA·cm^(−2).The optimized strategy for interfacial coupling of the fabricated Cu_(2)Se-V_(2)O_(5) catalyst resulted in a porous structure with accessible active sites,which enabled adsorption of the intermediates and afforded an effective charge transfer rate for promoting the oxygen evolution reaction.Furthermore,the combined effect of the catalyst components provided long-term stability for over 110 h in an alkaline solution,which makes the catalyst promising for large-scale practical applications.The aforementioned advantages of the composite catalyst overcome the limitations of low conductivity,agglomeration,and poor stability of the pure catalysts(Cu2Se and V2O5).展开更多
The utilization of CO2 and solar energy have drawn much attention due to global warming and fuel crisis. Of particular interest in our research, we prepared strontium zirconate(Sr Zr O3) nanoparticles as the photocata...The utilization of CO2 and solar energy have drawn much attention due to global warming and fuel crisis. Of particular interest in our research, we prepared strontium zirconate(Sr Zr O3) nanoparticles as the photocatalyst to convert CO2 into value-added products. Sr Zr O3 nanoparticles were successfully synthesized via a sonochemical method and applied to the photoreduction of CO2. The samples were characterized by X-ray diffraction, Raman spectroscopy, scanning electron microscopy, Brunauere Emmette Teller measurement, X-ray photoelectron spectroscopy and UV-vis absorption spectroscopy. Ethanol, methane and carbon monoxide were the major products with the yield respectively as follows, 41 μmol g-1, 2.57 μmol g-1 and 1.6 μmol g-1 after 4 h of reaction. The reason for the multiple photoreduction products is briefly discussed. Our work indicates that the as-prepared Sr Zr O3 nanoparticles can be used as a promising photocatalyst in turning CO2 into value-added chemicals.展开更多
文摘Reducing the production costs of clean energy carriers such as hydrogen through scalable water electrolysis is a potential solution for advancing the hydrogen economy.Among the various material candidates,our group demonstrated transition-metal-based materials with tunable electronic characteristics,various phases,and earth-abundance.Herein,electrochemical water oxidation using Cu_(2)Se-V_(2)O_(5) as a non-precious metallic electrocatalyst via a hydrothermal approach is reported.The water-splitting performance of all the fabricated electrocatalysts was evaluated after direct growth on a stainless-steel substrate.The electrochemically tuned Cu_(2)Se-V_(2)O_(5) catalyst exhibited a reduced overpotential of 128 mV and provided a reduced Tafel slope of 57 mV·dec^(−1) to meet the maximum current density of 250 mA·cm^(−2).The optimized strategy for interfacial coupling of the fabricated Cu_(2)Se-V_(2)O_(5) catalyst resulted in a porous structure with accessible active sites,which enabled adsorption of the intermediates and afforded an effective charge transfer rate for promoting the oxygen evolution reaction.Furthermore,the combined effect of the catalyst components provided long-term stability for over 110 h in an alkaline solution,which makes the catalyst promising for large-scale practical applications.The aforementioned advantages of the composite catalyst overcome the limitations of low conductivity,agglomeration,and poor stability of the pure catalysts(Cu2Se and V2O5).
基金supported by the Ministry of Science and Technology of China (2015DFG62610)Higher Education Commission (HEC) of Pakistan for the financial support under Post-Doctoral fellowship program
文摘The utilization of CO2 and solar energy have drawn much attention due to global warming and fuel crisis. Of particular interest in our research, we prepared strontium zirconate(Sr Zr O3) nanoparticles as the photocatalyst to convert CO2 into value-added products. Sr Zr O3 nanoparticles were successfully synthesized via a sonochemical method and applied to the photoreduction of CO2. The samples were characterized by X-ray diffraction, Raman spectroscopy, scanning electron microscopy, Brunauere Emmette Teller measurement, X-ray photoelectron spectroscopy and UV-vis absorption spectroscopy. Ethanol, methane and carbon monoxide were the major products with the yield respectively as follows, 41 μmol g-1, 2.57 μmol g-1 and 1.6 μmol g-1 after 4 h of reaction. The reason for the multiple photoreduction products is briefly discussed. Our work indicates that the as-prepared Sr Zr O3 nanoparticles can be used as a promising photocatalyst in turning CO2 into value-added chemicals.