High-throughput screening of piezo-photocatalytic materials for hydrogen production

Abstract: Finding cost-effective and efficient photocatalytic materials able to catalyse the water splitting reaction under visible light is one of the greatest challenges in current environmental material science. Despite that many photocatalysts are already known in the context of green hydrogen production, strategies to systematically and rationally modify their optoelectronic properties to achieve desired photocatalytic performance are yet to be established. Piezoelectric materials react to mechanical stimuli by adjusting their band gaps and band alignments, thus offering a possible route to precise photocatalyst design. However, piezo-photocatalysts are relatively scarce and have been seldom investigated to date. Here, we present a high-throughput screening of piezo-photocatalytic materials performed over $\sim 1,000$ bulk piezoelectrics that relies on a simple electrostatic model and first-principles calculations. A total of $\sim 10$ previously overlooked binary and tertiary bulk compounds are theoretically identified as highly promising piezo-photocatalysts due to their appropriate optoelectronic properties and superb band alignment tunability driven by uniaxial strain.