Nanogenerators for Energy Harvesting

Abstract

The use of electronic devices is an integral part of our everyday life and a major part of our activities with these devices is related to receiving, sending, and storing information. Some of these devices used for sensing, analysing, and transmitting signals require a very small amount of energy. An alternative source to power these devices could be through harvesting tiny mechanical motions associated with different types of motions. Nanogenerators (NG) are potential sources of energy harvesting by converting waste mechanical energies into useful electrical energy. NGs have already been commercialized in the health and automobile industry as pacemakers and tyre pressure monitoring systems, respectively. However, there is a wide scope of using them for common household and environment remediation applications, which is currently restricted due to the high cost of fabrication and low energy conversion efficiency. Vibrational energy associated with wind, flow of fluid, body movements, roads, train tracks, etc. can be converted to power devices locally and reduce the carbon footprint due to the energy produced by fossil fuels. This book chapter reviews the basic working of different nanogenerators based on piezoelectricity, triboelectricity pyroelectric, and flexoelectricity. Many non-lead-containing piezoelectric materials are promising candidates for piezoelectric nanogenerators (PENG) that can also be used for various self-powered electronic and biomedical devices. Many metal-oxides such as zinc-oxides and hafnium-oxides could be of special interest to this. Triboelectricnanogenerators (TENG) could be the most preferred device for harvesting water-wave blue-energy and integration with conventional electromagnetic-induction (generators) that can be deployed at a large-scale.