Influence of Bi-Cu microstructure on the photoelectrochemical performance of BiVO4 photoanode for efficient water splitting

To date, photoanodes containing bimetallic alloy nanoparticles (ANPs) are exposed good photoelectrochemical (PEC) performance for hydrogen production owing to their optoelectronic properties. In this work, low-cost, visible light active and environmental-friendly BiVO4/Bi-Cu nanocomposite photoanode is fabricated via organic decomposition and electrodeposition process. Transmission electron microscope images reveals that Bi-Cu ANPs are uniformly distributed on BiVO4 which can enhance the PEC performance. Typical results originate that BiVO4/Bi-Cu nanocomposite exhibits a high photocurrent density of 10.31 mA cm-2 at 1.23 V and solar-to-hydrogen conversion efficiency of 3.55%, which is higher than other electrodes. In addition, this composite shows excellent long-term stability over 5 h and low charge transfer resistance. These results suggest the introduction of Bi-Cu ANPs enhances the broadband light absorption of BiVO4 due to the excitation of localized surface plasmons at different wavelengths and also improves the charge transportation in the photoanode. Thus, BiVO4/Bi-Cu photoelectrode reports here is superior PEC performance for hydrogen generation providing an economical and feasible route to fabricate surface plasmon resonance (SPR)-enhanced composites as photocatalysts using earth-abundant Bi and Cu metals instead of noble-metals.