Fabrication of WO3 photoanode decorated with Au nanoplates and its enhanced photoelectrochemical properties

In the present work, we improved the photoelectrochemical (PEC) performance of tungsten trioxide (WO3) photoanode by decorating WO3 plates with Au nanoplates. WO3 plates were fabricated on FTO-coated glass by hydrothermal treatment and Au nanoplates were incorporated by immersing the substrates in Au nanoplates solution under different periods of time. Our study revealed that compared with pristine WO3, the Au-WO3 nanocomposite performed enhanced photocurrent density under irradiation of the simulated sunlight. This improved PEC performance was benefited from the extension of light absorption resulting from the surface plasmon resonance effect of Au nanoplates at about 650 nm wavelength, and it was verified by UV–vis absorption spectra. The incident photon-to-current conversion efficiency measurements revealed improved photoactivity after decoration of WO3 with Au nanoplates. This study provided a facile method to decorate Au nanoplates on WO3 photoanodes with enhanced performance for solar energy conversion. [Display omitted] •Au-WO3 photoanodes were fabricated by simply immersing WO3 in Au nanoplates solution.•Surface plasmon resonance of Au nanoplates resulted in enhanced light absorption.•With Au nanoplates decoration, the photoactivity was improved under simulated sunlight.•The improved photoelectrochemical properties of Au-WO3 photoanodes were studied.