Piezoelectric Energy Harvesting for Low-Power Smart Electronics

Abstract

In recent years, significant progress regarding energy harvesting has been made, owing to the need to replace conventional energy sources with alternative, green, and sustainable ones. Among them, mechanical energy harvesting is a promising strategy with outstanding characteristics of high conversion efficiency, facile fabrication process, simple structure, flexible selection of materials, and the ability to capture energy independent of season. Nowadays, the piezoelectric mechanism has gained attention from the research community as a prominent mechanical energy harvesting method. Diverse technologies in harvesting and sensing schemes have been innovatively developed alongside explorations of novel piezoelectric materials and the establishment of theoretical foundations. This article comprehensively reviews piezoelectric energy harvesting from the research background to its significance. The operation mechanisms of a piezoelectric nanogenerator (PENG) in various modes, including the theoretical principle of piezoelectricity, are discussed. Three generations of piezoelectric material development are explained, including structural designs of PENG for specific applications. Finally, highlighted applications of PENG in diverse fields such as energy harvesting and sensing, biomedical electronics, and novel intelligent sensing technologies, have been reviewed.