Highly-efficient photocatalytic hydrogen evolution enabled by piezotronic effects in SrTiO3/BaTiO3 nanofiber heterojunctions

The synergistic effect between piezoelectric and photocatalytic behaviors presents an interesting avenue to enhance the water-splitting processes for hydrogen production. Through a combination of experimental findings and theoretical calculations, we propose that the piezoelectric field inherent in these materials may decrease the bandgap of piezo-photocatalysts, while the Z-scheme heterojunction structure facilitates electron transfer. Leveraging the synergistic effects of heterojunction formation and piezoelectric assistance, we demonstrate that the incorporated piezoelectric BaTiO3 significantly enhances the hydrogen evolution rate of hybrid SrTiO3/BaTiO3 nanofibers to 1950.2 μmol·g–1·h–1. This surpasses the rates achieved by pure SrTiO3 and BaTiO3 counterparts by 2.4 and 4.1 times, respectively, and notably exceeds those of perovskite-based piezo-photocatalysts ever reported. The present work offers a valuable pathway for piezoelectric-assisted photocatalytic mechanism insight and sustainable hydrogen production, toward a remarkable advancement in pursuit of efficient and environmentally-friendly energy solutions.