Quantum dots and plasmonic Ag decorated WO3 nanorod photoanodes with enhanced photoelectrochemical performances

We firstly report a novel WO3/Ag/CdS NRs composite structure combining the surface plasmon resonance (SPR) function of Ag nanoparticles and CdS quantum dots (QDs) with one-dimensional (1D) WO3 nanorods (NRs) as photoanode for photoelectrochemical (PEC) water splitting. This new three components structure exhibits a remarkably high photoelectrocatalytic performance with a significant improved photocurrent density of 1.38 mA cm−2 was measured at 0.6 V vs Ag/AgCl, which about 3.54 times and 1.62 times higher than that of pristine WO3 NRs and WO3/CdS NRs. The enhanced performance of WO3/Ag/CdS NRs composite structure benefiting from the fast photogenerated charge carrier transmission in long light irradiation pathway because of 1D WO3 NRs. In addition, owing to SPR effect of Ag nanoparticles deposited on WO3 NRs and coupling with CdS QDs of appropriate energy band gap, light absorbance efficiency is enhanced and photogenerated electron-hole recombination rate is reduced. This facile composite structure presents a perspective on recent developments in modified photocatalyst for efficient photoelectrochemistry with an emphasis on water splitting.