Multi-modal optimization of bismuth vanadate photoanodes via combinatorial alloying and hydrogen processing

Abstract

Alloying transition metals, such as Mo, into BiVO₄ has emerged as the primary mechanism for improving carrier transport in this photoanode for solar fuels production. The present work establishes the generality of improving photoelectrochemical performance through co-alloying with a transition metal electron donor and a structure-modulating rare earth. Further improvement for all such alloys is obtained by annealing the oxide materials in H₂, ultimately producing photoanodes with above 3 mA cm⁻² photocurrent density under AM 1.5G illumination, in the top tier of compact BiVO₄ films.