LAUSR

Recently, ZnO-based piezoelectric nanogenerator has become a focus of many researchers because of its application prospect in self-powered micro/nanodevices. While the low efficiency of nanogenerators confines its development by piezoelectric screening effect due to the many excess free electrons in ZnO, in this paper, we demonstrate a novel and effective method to weaken the piezoelectric screening effect and enhance the output power of two-dimensional ZnO nanodisks-based NG by spin-coating a Spiro-MeOTAD layer on the surface of ZnO to form a PN junction. An average of 300 nA piezoelectric current of ZnO/Spiro nanogenerators is detected, which is nearly 10 times higher than that of pristine ZnO nanogenerators. The working principle is also analyzed theoretically by using multiphysics COMSOL software and space charge region diagram. The results verified that the formation of ZnO/Spiro-MeOTAD PN junction can successfully suppress the piezoelectric screening effect which could be applied to the development of self-powering micro/nanoelectrical devices.