Enhanced Piezo-photocatalytic Performances of AgNbO₃ Materials for Dye Decomposition Via Polarization Engineering

The limitation to enhancing photocatalytic performance in photocatalysts lies in the rapid recombination of photo-induced electrons and holes. Herein, AgNbO3 photocatalysts were synthesized by the hydrothermal method. The effects of hydrothermal temperature on the microstructure and photocatalytic/piezo-photocatalytic performances of AgNbO3 have been systematically investigated. The AgNbO3 cubes synthesized at 180 degrees C for 24 h exhibited the best photocatalytic/piezo-photocatalytic performances among all samples. The corona poling as an important method of polarization engineering is applied to promote further the separation and migration of charge carriers in AgNbO3. The polarized AgNbO3 synthesized at 170 degrees C exhibited outstanding piezo-photocatalytic performance, and a degradation rate of 95 % for RhB within 90 min and a high apparent rate constant of 0.02978 min(-1) were achieved. On the one hand, the alternating piezoelectric field caused by ultrasonic-assisted illumination destroyed the shielding effect and enhanced the separation of electron-hole pairs. On the other hand, polarization engineering induced by corona poling promoted the separation and migration of photo-induced carriers, thereby realizing more efficient utilization of these charges during the photocatalytic decomposition process. This work presents a facile way to achieve superior piezo-photocatalytic performances of AgNbO3-based photocatalyst via polarization engineering.