Plasmonic Pd Nanoparticle- and Plasmonic Pd Nanorod-Decorated BiVO(4) Electrodes with Enhanced Photoelectrochemical Water Splitting Efficiency Across Visible-NIR Region

The photoelectrochemical (PEC) water splitting performance of BiVO(4) is partially hindered by insufficient photoresponse in the spectral region with energy below the band gap. Here, we demonstrate that the PEC water splitting efficiency of BiVO(4) electrodes can be effectively enhanced by decorating Pd nanoparticles (NPs) and nanorods (NRs). The results indicate that the Pd NPs and NRs with different surface plasmon resonance (SPR) features delivered an enhanced PEC water splitting performance in the visible and near-infrared (NIR) regions, respectively. Considering that there is barely no absorption overlap between Pd nanostructures and BiVO(4) and the finite-difference time domain (FDTD) simulation indicating there are substantial energetic hot electrons in the vicinity of Pd nanostructures, the enhanced PEC performance of Pd NP-decorated BiVO(4) and Pd NR-decorated BiVO(4) could both benefit from the hot electron injection mechanism instead of the plasmon resonance energy transfer process. Moreover, a combination of Pd NPs and NRs decorated on the BiVO(4) electrodes leads to a broad-band enhancement across visible-NIR region.