Low-frequency flexible piezoelectric nanogenerators based on ZnO nanorods grown on Cu wires

A self-powering nanosystem that harvests its operating energy from the environment is an attractive proposition for sensing and personal electronics. In this paper, we present a simple, low-cost approach to convert low-frequency mechanical energy into electric power using piezoelectric ZnO nanorods grown on common Cu wires. This energy conversion device has ultrahigh flexibility and piezoelectric sensitivity and can produce an output current of about 50 nA, which can last for almost 5 seconds. Furthermore, the I–V curves of the device under different strains are also examined, and the I–V characteristic is highly sensitive to strain. This energy-harvesting technology provides a simple and cost-effective platform to capture low-frequency mechanical energy, such as body movements, for practical applications.