Fabrication of a Novel Co/CoO@Fe₂V₄O₁₃ Composite Catalyst as a Photoanode for Enhanced Photoelectrochemical Water Oxidation

Herein, the synthesis of a novel composite photocatalyst, Co/CoO@Fe₂V₄O₁₃, is reported by the deposition of CoO metal oxide nanoparticles on the surface of Fe₂V₄O₁₃ bimetallic oxide. The synthesised photocatalyst exhibited a band gap of roughly 1.8 eV, rendering it responsive to the complete visible light spectrum of the sun, thereby enabling optimal absorption of solar radiation. The Co/CoO@Fe₂V₄O₁₃ composites demonstrated an enhanced photoelectrochemical water oxidation capacity compared to pristine Fe₂V₄O₁₃ when exposed to visible light. The enhanced performance is attributed primarily to the creation of a p-n junction at the interface of Fe₂V₄O₁₃ and Co/CoO, as well as the Z-scheme charge transfer mechanism, which aids in the separation and transfer of photogenerated charge carriers. Light absorption by Co nanoparticles via plasmonic excitation and intra- and inter-band transitions in the composite structure is also likely, resulting in increased composite efficiency. Our findings indicate that Co/CoO@Fe₂V₄O₁₃ composites show promising performance for solar water splitting applications and offer new perspectives for designing effective photocatalysts.