Facile and scalable fabrication of Ag-modified BiVO4 photoanodes for enhanced photoelectrochemical water splitting

Photoelectrochemical (PEC) water splitting offers a sustainable pathway for hydrogen production, however, the practical application of bismuth vanadate (BiVO 4 ) photoanodes is severely limited by inefficient charge separation and sluggish surface reaction kinetics.To address these challenges, this work aims to develop a simple, scalable, and interface-engineered strategy to enhance the PEC activity of BiVO 4 photoanodes. Herein, Ag-modified BiVO 4 photoanodes were prepared via a scalable two-step electrodeposition followed by photodeposition process, enabling controllable Ag loading and robust interfacial contact. The introduction of Ag nanoparticles not only enhances visible-light absorption through plasmonic effects, but also promotes charge separation by acting as effective electron sinks at the BiVO 4 /Ag interface. As a result, the optimized BiVO 4 /Ag-2 electrode delivers a photocurrent density of 1.24 mA·cm -2 at 1.23 V vs. RHE, which is 2.6 times higher than that of pristine BiVO 4 , along with a surface charge injection efficiency of 35.9%. Moreover, the electrode retains 80.3% of its initial photocurrent after 3 h of continuous operation without sacrificial agents, demonstrating improved operational stability. These findings highlight the synergistic effects of scalable fabrication, controlled Ag decoration, and plasmon-assisted charge transfer regulation, providing a practical and manufacturable design strategy for advancing BiVO 4 -based photoanodes toward efficient solar-driven water splitting.