Controlled growth of ZnO nanorods on common paper substrate and their application for flexible piezoelectric nanogenerators

A simple and effective method of synthesizing nanorods (NRs) and the ability to control the size and aspect ratio of them are crucial for fabricating nanodevices. In this paper, we present a systematic study of the growth of ZnO NRs on common paper substrates using a hydrothermal approach by adjusting the growth conditions. By a slight variation of the solution concentration and the growth time, significant changes in morphology and size (aspect ratio) of the obtained ZnO NRs have been controlled. Moreover, the piezoelectric power generation from ZnO-paper nanogenerators grown with different precursor concentration and growth time are also investigated. It is found that the morphology and aspect ratio of NRs have significant influence on the piezoelectric behavior. This type of flexible piezoelectric nanogenerator will have potential applications in implantable biosensors and wearable self-powered electronic devices.