Bismuth Vanadate as a Platform for Accelerating Discovery and Development of Complex Transition-Metal Oxide Photoanodes

Development
of practical systems for photoelectrochemical conversion
of solar energy to chemical fuel requires light absorbers that are
efficient, durable, and scalable. Because no material currently meets
all three requirements, intensive semiconductor discovery efforts
are underway, with a major focus on complex metal oxides. Discovery
and development of next-generation light absorbers can be accelerated
by gaining mechanistic insights into the function of existing systems.
BiVO4 embodies many key characteristics of the broader
class of transition-metal oxides. Thus, it is well-suited as a platform
for elucidating the critical roles of charge localization, defects,
and chemical interactions on photoelectrochemical performance characteristics.
In this Perspective, we discuss how comprehensive characterization
of electronic structure and semiconductor properties can advance theoretical
models, approaches to addressing inefficiencies and instabilities,
and prediction of new materials. Studies of BiVO4 provide
a general framework for understanding mechanisms in emerging materials
and a foundation for discovering new ones.