The internal electric field within a piezoelectric material can effectively inhibit the recombination of photogenerated electron-hole pairs, thus serving as a means to enhance photocatalytic efficiency. Herein, we synthesized a Na0.5Bi4.5Ti4O15 (NBT) catalyst by the hydrothermal method and optimized its catalytic performance by simple high-voltage poling. When applying light and mechanical stirring on a 2 kV mm-1 poled NBT sample, almost 100% of Rhodamine B solution could be degraded in 120 min, and the reaction rate constant reached as high as 28.36 × 10-3 min-1, which was 4.2 times higher than that of the unpoled NBT sample. The enhanced piezo-photocatalytic activity is attributed to the poling-enhanced internal electric field, which facilitates the efficient separation and transfer of photogenerated carriers. Our work provides a new option and idea for the development of piezo-photocatalysts for environmental remediation and pollutant treatment.
Keywords: Na0.5Bi4.5Ti4O15; piezo-photocatalysis; piezoelectric effect; poling process.