Poling‐induced Enhancement of Piezocatalytic Performance of 0.96k0.5na0.5nbo3‐0.04bi0.5na0.5zro3 Ceramic Blocks

Compared with powder particles, ceramic block piezocatalyst possesses the advantages of high cycle stability, decreasing secondary pollution, and easy recovery. Herein, with a simple strategy of the poling procedure, the piezocatalytic activity of 0.96K(0.5)Na(0.5)NbO(3)-0.04Bi(0.5)Na(0.5)ZrO(3) (abbreviated as 0.96KNN-0.04BNZ) ceramic blocks can be considerably improved. A reaction rate constant k value of 14.70x10(-3) min(-1) in the poled sample can be obtained to degrade Rhodamine B, which is 3.44 times that of the unpoled one. Meanwhile, the poled sample also has good degradation effects against methylene blue and amino black 10B. The improvement of piezocatalytic activities originates from the reduction of crystal symmetry and the enhancement of electron-hole pair separation, which accelerates the generation of charge carriers. This research displays a unique lead-free bulk piezocatalyst and a convenient method for enhancing its piezocatalytic activity.