Piezoelectric Nanogenerators Based on Zinc Oxide Nanowire Arrays

TLDR

The study proposes using ZnO nanowire arrays to convert mechanical, vibrational, or hydraulic energy into electricity for powering nanodevices. Aligned ZnO nanowires are bent by a conductive AFM tip, generating strain‑induced charge separation and a Schottky barrier that rectifies the flow into electrical current. The nanogenerator converts nanoscale mechanical energy into electrical energy with an estimated efficiency of 17–30 %.

Abstract

We have converted nanoscale mechanical energy into electrical energy by means of piezoelectric zinc oxide nanowire (NW) arrays. The aligned NWs are deflected with a conductive atomic force microscope tip in contact mode. The coupling of piezoelectric and semiconducting properties in zinc oxide creates a strain field and charge separation across the NW as a result of its bending. The rectifying characteristic of the Schottky barrier formed between the metal tip and the NW leads to electrical current generation. The efficiency of the NW-based piezoelectric power generator is estimated to be 17 to 30%. This approach has the potential of converting mechanical, vibrational, and/or hydraulic energy into electricity for powering nanodevices.