Ferroelectricity and Schottky Heterojunction Engineering in AgNbO3: A Simultaneous Way of Boosting Piezo-photocatalytic Activity

As an efficient and economical way of dealing with organic pollutants, piezo-photocatalysis has attracted great interest. In this work, we demonstrated that ferroelectricity and Schottky heterojunction engineering could significantly enhance the piezo-photocatalytic activity of AgNbO3. The poled 20 mol % K+ doped AgNbO3 disclosed its superior piezo-photocatalytic activity of 0.131 min-1 for 10 mg·L-1 RhB, which is 7.8 times of the pristine one under the condition of illumination only. The designed piezo-photocatalyst also exhibited good piezo-photocatalytic stability after four cycles. These merits are attributed to the built-in electric field associated with the large spontaneous polarization and low coercive field originated from the stable ferroelectric state after ferroelectricity engineering, plus with the electron trapper effect of the in situ precipitated metal Ag particles. Our work not only provides a promising piezo-photocatalyst for degrading organic contaminants but also paves a good way for developing high piezo-photocatalytic activity catalysts.