Abstract

Piezoelectric semiconductors, such as wurtzite structure ZnO, GaN, and InN, have novel properties of coupling of piezoelectric and semiconductor. The piezoelectric field is created inside ZnO nanowires by applying strain. The photo-generated electrons and holes will be separated under the driving of piezoelectric field. The photocatalytic activity of ZnO nanowires for degrading methylene blue has been enhanced by the piezoelectric-driven separation of photo-generated carriers. Coupling the piezoelectric and photocatalytic properties of ZnO nanowires, a new fundamental mechanism for the degradation of organic dye has been demonstrated.