表面Au负载对BiVO_(4)纳米多孔膜光电化学性能的影响

Effect of surface Au loading on photoelectrochemical performance of BiVO_(4) nano porous films

采用电化学沉积法在透明导电玻璃衬底上成功制备出高表面积的BiVO_(4)纳米多孔光阳极,研究了表面Au负载对其光电化学(PEC)性能的影响。利用SEM、UV-Vis、PEC性能评价及电化学阻抗谱等对其进行分析。结果表明,Au负载并未显著改变样品形貌;Au负载有助于增强材料在可见光区的吸收;Au负载有利于增强BiVO_(4)光阳极的光电流,使其1.23 V时的光电流由1.24 mA/cm^(2)增强至2.24 mA/cm^(2),提高了近1倍;材料PEC性能的增强来自于固体电极/电解液界面特性的改善。同时,通过构筑光电化学电池评价样品的实际产氢性能发现,Au负载有助于大幅提升材料的产氢性能,可由33.2μmol/(cm^(2)·h)增至59.5μmol/(cm^(2)·h)。

Nano porous BiVO_(4)photoanodes with high surface area are successfully prepared on transparent conductive glass substrates by a facile electrochemical deposition.The effect of surface Au loading on its photoelectrochemical(PEC) performance is investigated.SEM results show that Au loading has not changed the sample morphology significantly.UV-Vis results show that Au loading is conducive to the absorption in visible light region.PEC results show that Au loading is conducive to enhance the photocurrent of BiVO_(4)photoanode, which is nearly doubled from 1.24 mA·cm^(-2)to 2.24 mA·cm^(-2)at 1.23 V.The electrochemical impedance spectroscopy(EIS) reveals that the enhanced PEC performance comes from the improved interface quality of solid electrode/electrolyte.Furthermore, a PEC cell is constructed to evaluate the actual H_(2)production performance.It is found that Au loading is helpful to improve the material’s H_(2)production performance greatly from 33.2 μmol·cm^(-2)·h^(-1)to 59.5 μmol·cm^(-2)·h^(-1).