Synergistic enhancement of photovoltaic performance of TiO2 photoanodes by incorporation of Dawson-type polyoxometalate and gold nanoparticles

To explore the synergistic effects of polyoxometalate and noble metal nanoparticles on the photovoltaic performance of titanium dioxide (TiO2), multilayer film photoanodes consisting of TiO2 nanoparticles, gold nanoparticles (Au) and Dawson-type polyoxometalate K6P2W18O62 (abbr. as P2W18) have been prepared by the layer-by-layer self-assembly method, and poly(styrenesulfonate) (PSS) was used as a film forming auxiliary material. These film electrodes were characterized by UV-vis spectra, X-ray photoelectron spectroscopy, atomic force microscopy, and photoelectrochemical measurements. Transient photocurrent and current-voltage curve measurements demonstrate that the photocurrent response and power conversion efficiency increase in the sequence: the TiO2 film < the P2W18/TiO2 film < the TiO2/P2W18/Au film. These results provide valuable information for photovoltaic and photoelectrochemical applications.