Study on the charge carrier transport property generated by photo/piezo synergy field over barium strontium titanate

The combination of piezoelectric catalysis and photocatalysis has garnered significant attention in the fields of pollutant degradation and water splitting. However, the charge carrier transport property remains unclear due to the difficulty in observing nanocrystal polarization during the reaction process. This study aimed to address this issue by preparing Ba 1−x Sr x TiO 3 (BST) solid solutions using the solid-phase method and examining the effect of ion doping on piezoelectricity-photocatalytic activity. The photocatalysis and local piezoelectric catalysis coupling was evaluated through water decomposition and dye degradation. Interestingly, the introduction of local piezoelectric catalysis had the opposite effect: it reduced photocatalytic hydrogen production but increased the rate of photocatalytic RhB degradation. The possible mechanism was proposed that the different adsorption of H + and radicals on the catalysts would affect the direction of the local piezoelectric potential and then change the photo-generated carriers' transfer path.