A[H3AgI(H2O)PW11O39]3?‐TiO2/ITO electrode was fabricated by immobilizing a molecular polyoxometalate‐based water oxidation catalyst,[H3AgI(H2O)PW11O39]3?(AgPW11),on a TiO2electrode.The resulting electrode was charac...A[H3AgI(H2O)PW11O39]3?‐TiO2/ITO electrode was fabricated by immobilizing a molecular polyoxometalate‐based water oxidation catalyst,[H3AgI(H2O)PW11O39]3?(AgPW11),on a TiO2electrode.The resulting electrode was characterized by X‐ray powder diffraction,scanning electron microscopy,and energy dispersive X‐ray spectroscopy.Linear sweep voltammetry,chronoamperometry,and electrochemical impedance measurements were performed in aqueous Na2SO4solution(0.1molL?1).We found that a higher applied voltage led to better catalytic performance by AgPW11.The AgPW11‐TiO2/ITO electrode gave currents respectively10and2.5times as high as those of the TiO2/ITO and AgNO3‐TiO2/ITO electrodes at an applied voltage of1.5V vs Ag/AgCl.This result was attributed to the lower charge transfer resistance at the electrode‐electrolyte interface for the AgPW11‐TiO2/ITO electrode.Under illumination,the photocurrent was not obviously enhanced although the total anode current increased.The AgPW11‐TiO2/ITO electrode was relatively stable.Cyclic voltammetry of AgPW11was performed in phosphate buffer solution(0.1mol L?1).We found that oxidation of AgPW11was a quasi‐reversible process related to one‐electron and one‐proton transfer.We deduced that disproportionation of the oxidized[H2AgII(H2O)PW11O39]3?might have occurred and the resulting[H3AgIIIOPW11O39]3?oxidized water to O2.展开更多
基金supported by the National Natural Science Foundation of China (21573099, 21601077, 21573100)~~
文摘A[H3AgI(H2O)PW11O39]3?‐TiO2/ITO electrode was fabricated by immobilizing a molecular polyoxometalate‐based water oxidation catalyst,[H3AgI(H2O)PW11O39]3?(AgPW11),on a TiO2electrode.The resulting electrode was characterized by X‐ray powder diffraction,scanning electron microscopy,and energy dispersive X‐ray spectroscopy.Linear sweep voltammetry,chronoamperometry,and electrochemical impedance measurements were performed in aqueous Na2SO4solution(0.1molL?1).We found that a higher applied voltage led to better catalytic performance by AgPW11.The AgPW11‐TiO2/ITO electrode gave currents respectively10and2.5times as high as those of the TiO2/ITO and AgNO3‐TiO2/ITO electrodes at an applied voltage of1.5V vs Ag/AgCl.This result was attributed to the lower charge transfer resistance at the electrode‐electrolyte interface for the AgPW11‐TiO2/ITO electrode.Under illumination,the photocurrent was not obviously enhanced although the total anode current increased.The AgPW11‐TiO2/ITO electrode was relatively stable.Cyclic voltammetry of AgPW11was performed in phosphate buffer solution(0.1mol L?1).We found that oxidation of AgPW11was a quasi‐reversible process related to one‐electron and one‐proton transfer.We deduced that disproportionation of the oxidized[H2AgII(H2O)PW11O39]3?might have occurred and the resulting[H3AgIIIOPW11O39]3?oxidized water to O2.
