Surface modification of InVO4 nanoparticles on WO3 plate array films for improved photoelectrochemical performance

Abstract

We have successfully synthesized InVO₄ nanoparticles on the surface of WO₃ nanoplate arrays on FTO substrates using a dipping–annealing method. The InVO₄/WO₃ film has a 2 times higher photocurrent density than the pure WO₃ films and possesses a better PEC performance under visible light irradiation. The highest incident-photo-to-current-efficiency (IPCE) value of the WO₃ nanoplate arrays increases from 25.2% to 55.3% after modified by InVO₄. The InVO₄/WO₃ film had a larger optical absorption, larger carrier density, longer electron lifetime and more negative flat band potential. Besides that, the improved photoelectrochemical performance was mainly attributed to the effective separation of photogenerated electron–hole pairs at the interface. The investigation demonstrates that metal orthovanadates may be good surface modifiers to cover on WO₃ to provide promising photoelectrodes for photocatalysis.