Enhanced BiVO4 Photoanode Photoelectrochemical Performance via Borate Treatment and a NiFeOx Cocatalyst

To settle the slow water oxidation kinetics and charge recombination of BiVO4 photoanodes, boron-treated BiVO4 combined with a NiFeOx electrocatalyst (NiFeOx/B/BiVO4) electrode is prepared. The resultant NiFeOx/B/BiVO4 demonstrates a 5.22 mA/cm(2) current density at 1.23 V vs RHE under AM 1.5 G illumination without any sacrificial agent. Significantly, the applied bias photon-to-current efficiency of the NiFeOx/B/BiVO4 photoanode reaches 1.96% at 0.7 V vs RHE, which is much higher than that of pristine BiVO4. Such excellent performance can be attributed to the existence of self-adsorbed [B(OH)(4)](-) ligands and NiFeOx electrocatalysts, enhancing the separation of photoelectron-hole pairs. This work provides a way to construct effective photocatalysts for solar water splitting.

Automated summary

The combination of boron-treated BiVO4 with NiFeOx electrocatalyst (NiFeOx/B/BiVO4) demonstrates excellent performance as a photoanode under solar illumination, achieving high current density at lower voltages without the need for sacrificial agents. This is largely attributed to the presence of [B(OH)4](-) ligands and NiFeOx electrocatalysts, which enhance the separation efficiency of photoelectron-hole pairs. This work provides a promising approach for developing efficient photocatalysts for solar water splitting.