Ternary WO3/Porous-BiVO4/FeOOH Hierarchical Architectures: Towards Highly Efficient Photoelectrochemical Performance

Developing photoanodes showing both a high solar harvesting efficiency and efficient charge separation/transfer is recognized as one of the key challenges for water splitting. In the presented work, we report a strongly coupled ternary WO3/porous-BiVO4/FeOOH hierarchical architecture as photoanode for high PEC performance,which was constructed by unique foaming-assisted electro-spraying of porous BiVO4 frameworks and photodeposition of a FeOOH layer, respectively. As a proof of concept, the as-fabricated WO3/porous-BiVO4/FeOOH photoanode yielded a photocurrent density of similar to 4.4 mA cm(-2) at 1.23 V vs. RHE, similar to 4 and 10 times higher than that of the BiVO4 and WO3 counterparts, respectively. Because of the surface passivation of FeOOH, the onset potential could be substantially reduced to similar to 200 mV in the presence of sacrificial agent under AM 1.5G (100 mW cm(-2)) simulated sunlight illumination, which was lowered by similar to 100 mV in comparison to those of BiVO4 and WO3 analogues. The mechanism for the enhanced PEC activities of ternary WO3/porous-BiVO4/FeOOH hierarchical architectures was proposed.