Recent progress in nanocomposite-oriented triboelectric and piezoelectric energy generators: An overview

Abstract

The demand for alternative energy is increasing globally, leading to the increased importance of energy harvesting technologies. Research is being conducted on the manufacture of piezoelectric (PENG), triboelectric (TENG) and electromagnetic nanogenerators (EMG), pyroelectric nanogenerators, electrochemical cells and solar cells, which transform thermal, mechanical, magnetic, chemical and solar energy into electrical energy. Furthermore, work is being done to create advanced hybrid systems that can convert multiple forms of energy into electrical energy simultaneously and adapt to different electronic devices and work environments. It is evident that advances in technology are essential for the development of TENGs, whose performance is influenced by the properties of their constituent elements. Fifty-five percent of the published literature focuses on TENGs, with 34.5% focusing on nanocomposites, owing to their improved properties and potential use in the fabrication of TENGs. However, piezoelectric nanogenerators (PENGs) can also enable low-power electronic devices to collect energy from the motions of biological systems. They demonstrate extraordinary piezoelectric capabilities and a higher power density, conversion efficiency and durability than earlier published prototype nanogenerators. Together, the high open circuit voltage (120 V) and low short circuit current (1.95 A) of PENGs result in a high-power density (7091 Vq).