Mechanism of interface engineering for ultrahigh piezo-photoelectric catalytic coupling effect of BaTiO3@TiO2 microflowers

Abstract

The built-in electric field of piezoelectric material is a widely considered reason for improved photocatalytic performance. In this paper, BaTiO3@TiO2 microflowers are demonstrated ultrahigh piezo-photo catalytic ability, of which the rate constant reaches 0.274 min−1 for 10 mg/L rhodamine B degradation. The degradation rate is almost 0 in dark, but reaches 0.084 min−1 under light irradiation. After deducting the difference in specific surface area, the rate constant of BaTiO3@TiO2 is 0.128 min−1 m−2, which is 10 times higher than that of pure TiO2 (0.012 min−1 m−2). These results indicate that the interface between BaTiO3 and TiO2 plays a major role to facilitate the separation of carriers, and it is also the uniqueness of this work. The mechanism of the interfacial enhanced piezo-phototronic effect is demonstrated by combining DFT modeling calculation and COMSOL simulation. This work proves that interface engineering is an effective route to enhance the performance of piezo-photoelectric catalysis.