Although monoclinic WO3 is widely studied as a prototypical photoanode material for solar water splitting,limited success,hitherto,in fabricating WO3 photoanodes that simultaneously demonstrate high efficiency and rep...Although monoclinic WO3 is widely studied as a prototypical photoanode material for solar water splitting,limited success,hitherto,in fabricating WO3 photoanodes that simultaneously demonstrate high efficiency and reproducibility has been realized.The difficulty in controlling both the efficiency and reproducibility is derived from the ever-changing structures/compositions and chemical environments of the precursors,such as peroxytungstic acid and freshly prepared tungstic acid,which render the fabrication processes of the WO3 photoanodes particularly uncontrollable.Herein,a highly reproducible sol-gel process was developed to establish efficient and translucent WO3 photoanodes using a chemically stable ammonium metatungstate precursor.Under standard simulated sunlight of air mass 1.5 G,100 m W cm-2,the WO3 photoanode delivered photocurrent densities of ca.2.05 and2.25 m A cm^-2at 1.23 V versus the reversible hydrogen electrode(RHE),when tested in 1 mol L^-1H2SO4 and CH3SO3H,respectively.Hence,the WO3 photoanodes fabricated herein are one of the WO3 photoanodes with the highest performance ever reported.The reproducibility of the fabrication scheme was evaluated by testing 50 randomly selected WO3 samples in1 mol L^-1H2SO4,which yielded an average photocurrent density of 1.8 m A cm^-2at 1.23 VRHEwith a small standard deviation.Additionally,the effectiveness of the ammonium metatungstate precursor solution was maintained for at least 3weeks,when compared with the associated upper-limit values of peroxytungstic and tungstic acid-based precursors after 3 d.This study presents a key step to the future development of WO3 photoanodes for efficient solar water splitting.展开更多
基金supported by the Ministry of Education(MOE)Tier 1(M4011959 and M4011528)the National Key Research and Development Program of China(2018YFA0209303)+1 种基金the National Natural Science Foundation of China(U1663228 and 51902153)the Project Funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions。
文摘Although monoclinic WO3 is widely studied as a prototypical photoanode material for solar water splitting,limited success,hitherto,in fabricating WO3 photoanodes that simultaneously demonstrate high efficiency and reproducibility has been realized.The difficulty in controlling both the efficiency and reproducibility is derived from the ever-changing structures/compositions and chemical environments of the precursors,such as peroxytungstic acid and freshly prepared tungstic acid,which render the fabrication processes of the WO3 photoanodes particularly uncontrollable.Herein,a highly reproducible sol-gel process was developed to establish efficient and translucent WO3 photoanodes using a chemically stable ammonium metatungstate precursor.Under standard simulated sunlight of air mass 1.5 G,100 m W cm-2,the WO3 photoanode delivered photocurrent densities of ca.2.05 and2.25 m A cm^-2at 1.23 V versus the reversible hydrogen electrode(RHE),when tested in 1 mol L^-1H2SO4 and CH3SO3H,respectively.Hence,the WO3 photoanodes fabricated herein are one of the WO3 photoanodes with the highest performance ever reported.The reproducibility of the fabrication scheme was evaluated by testing 50 randomly selected WO3 samples in1 mol L^-1H2SO4,which yielded an average photocurrent density of 1.8 m A cm^-2at 1.23 VRHEwith a small standard deviation.Additionally,the effectiveness of the ammonium metatungstate precursor solution was maintained for at least 3weeks,when compared with the associated upper-limit values of peroxytungstic and tungstic acid-based precursors after 3 d.This study presents a key step to the future development of WO3 photoanodes for efficient solar water splitting.