A novel 2D/2D Bi_(2)MoO_(6)/g-C_(3)N_(4) step-scheme(S-scheme)composite by loading Au as cocatalyst was successfully fabricated using a photoreduction and hydrothermal route.The obtained Bi_(2)MoO_(6)/g-C_(3)N_(4)/Au ...A novel 2D/2D Bi_(2)MoO_(6)/g-C_(3)N_(4) step-scheme(S-scheme)composite by loading Au as cocatalyst was successfully fabricated using a photoreduction and hydrothermal route.The obtained Bi_(2)MoO_(6)/g-C_(3)N_(4)/Au photocatalysts were characterized by X-ray diffraction(XRD),transmission electron microscope(TEM),X-ray photo-electron spectroscopy(XPS),UV–vis diffuse reflectance spectra(UV–vis),Fourier transform infrared spectroscopy(FTIR),photoluminescence(PL),photocurrent response(I-t),and electrochemical impedance spectroscopy(EIS).The HRTEM images revealed that an intimate interface in composites were formed.The optimum photocatalytic activity of Rhodamine B degradation over Bi_(2)MoO_(6)/g-C_(3)N_(4)/Au was about 9.7 times and 13.1 times as high as those of Bi_(2)MoO_(6) and g-C_(3)N_(4),respectively.The notably improved photocatalytic activity of Bi_(2)MoO_(6)/g-C_(3)N_(4)/Au could be mainly ascribed to the abundant active sites and the enhanced separation efficiency of photogenerated carriers in Bi_(2)MoO_(6)/g-C_(3)N_(4) S-scheme system.Notably,Au nanoparticles could act as a co-catalyst to further promote electron transfer and separation from the conduction band of g-C_(3)N_(4).Additionally,a possible step-scheme photocatalytic reaction mechanism of Rh B degradation over Bi_(2)MoO_(6)/g-C_(3)N_(4)/Au was tentatively proposed.PL and transient photocurrent analysis implied that Bi_(2)MoO_(6)/g-C_(3)N_(4)/Au photocatalysts possessed the lower recombination rate of photogenerated carriers compared with pure Bi_(2) MoO_(6) and g-C_(3)N_(4),respectively.The present work is expected to provide useful information in designing 2D/2D S-scheme heterojunction photocatalysts.展开更多
Water is considered to be an inhibitor of CO oxidation.The mechanism of retarding the reaction is thought to contribute to the practical application of CO oxidation,which is investigated by constructing the coupling o...Water is considered to be an inhibitor of CO oxidation.The mechanism of retarding the reaction is thought to contribute to the practical application of CO oxidation,which is investigated by constructing the coupling of Au nanoparticles and defective CuO to form metal-support interactions(MSI)and oxygen vacancies(OVs).The introduction of Au forms a new CO adsorption site,which successfully solves the competitive adsorption problem of CO with H2O and O_(2).Due to the coupling of MSI and OVs,the reduced ability of catalyst and the activation and migration ability of oxygen are enhanced simultaneously.Au-CuO has the ability to oxidize CO at room temperature with high stability under a humid environment.Theoretical calculation confirmed the competitive adsorption and the influence of MSI and OVs coupling on the catalyst performance.The mechanism of water resistance in CO catalytic oxidation was also explained.展开更多
基金financially supported by the Fundamental Research Funds for the Central Universities(No.JUSRP51716A)the National Natural Science Foundation of China(Nos.21203077 and 21773099)the financially support from the Qing Lan Project of Jiangsu Province。
文摘A novel 2D/2D Bi_(2)MoO_(6)/g-C_(3)N_(4) step-scheme(S-scheme)composite by loading Au as cocatalyst was successfully fabricated using a photoreduction and hydrothermal route.The obtained Bi_(2)MoO_(6)/g-C_(3)N_(4)/Au photocatalysts were characterized by X-ray diffraction(XRD),transmission electron microscope(TEM),X-ray photo-electron spectroscopy(XPS),UV–vis diffuse reflectance spectra(UV–vis),Fourier transform infrared spectroscopy(FTIR),photoluminescence(PL),photocurrent response(I-t),and electrochemical impedance spectroscopy(EIS).The HRTEM images revealed that an intimate interface in composites were formed.The optimum photocatalytic activity of Rhodamine B degradation over Bi_(2)MoO_(6)/g-C_(3)N_(4)/Au was about 9.7 times and 13.1 times as high as those of Bi_(2)MoO_(6) and g-C_(3)N_(4),respectively.The notably improved photocatalytic activity of Bi_(2)MoO_(6)/g-C_(3)N_(4)/Au could be mainly ascribed to the abundant active sites and the enhanced separation efficiency of photogenerated carriers in Bi_(2)MoO_(6)/g-C_(3)N_(4) S-scheme system.Notably,Au nanoparticles could act as a co-catalyst to further promote electron transfer and separation from the conduction band of g-C_(3)N_(4).Additionally,a possible step-scheme photocatalytic reaction mechanism of Rh B degradation over Bi_(2)MoO_(6)/g-C_(3)N_(4)/Au was tentatively proposed.PL and transient photocurrent analysis implied that Bi_(2)MoO_(6)/g-C_(3)N_(4)/Au photocatalysts possessed the lower recombination rate of photogenerated carriers compared with pure Bi_(2) MoO_(6) and g-C_(3)N_(4),respectively.The present work is expected to provide useful information in designing 2D/2D S-scheme heterojunction photocatalysts.
基金supported by the National Natural Science Foundation of China(Grant nos.51772183 and 52072230).
文摘Water is considered to be an inhibitor of CO oxidation.The mechanism of retarding the reaction is thought to contribute to the practical application of CO oxidation,which is investigated by constructing the coupling of Au nanoparticles and defective CuO to form metal-support interactions(MSI)and oxygen vacancies(OVs).The introduction of Au forms a new CO adsorption site,which successfully solves the competitive adsorption problem of CO with H2O and O_(2).Due to the coupling of MSI and OVs,the reduced ability of catalyst and the activation and migration ability of oxygen are enhanced simultaneously.Au-CuO has the ability to oxidize CO at room temperature with high stability under a humid environment.Theoretical calculation confirmed the competitive adsorption and the influence of MSI and OVs coupling on the catalyst performance.The mechanism of water resistance in CO catalytic oxidation was also explained.