Tunable Photocatalytic Activity of CoFe Prussian Blue Analogue Modified SrTiO₃ Core–Shell Structures for Solar-Driven Water Oxidation

Abstract

This study presents a pioneering semiconductor-catalyst core–shell architecture designed to enhance photocatalytic water oxidation activity significantly. This innovative assembly involves the in situ deposition of CoFe Prussian blue analogue (PBA) particles onto SrTiO3 (STO) and blue SrTiO3 (bSTO) nanocubes, effectively establishing a robust p–n junction, as demonstrated by Mott–Schottky analysis. Of notable significance, the STO/PB core–shell catalyst displayed remarkable photocatalytic performance, achieving an oxygen evolution rate of 129.6 μmol g–1 h–1, with stability over an extended 9-h in the presence of S2O8 2– as an electron scavenger. Thorough characterization unequivocally verified the precise alignment of the band energies within the STO/PB core–shell assembly. Our research underscores the critical role of tailored semiconductor-catalyst interfaces in advancing the realm of photocatalysis and its broader applications in renewable energy technologies.