A Critical Review on Triboelectric Nanogenerators (TENGs) with Flame Retardant, Antibacterial, Self-Cleaning, or Water Repellent Properties

Triboelectric nanogenerators (TENGs) can harness ambient mechanical energy and convert it into electrical energy. They are essential in ushering in the Internet of Things by acting as power sources and sensors. When such TENGs are to be used in special environments, like in extreme heat conditions or even to scavenge water energy or are to be saved from moisture or bacterial damage, they have to be imparted with special properties to endure the same. This review summarizes the recent developments that have taken place in this area of flame retardant, antibacterial, water repellent, and self-cleaning TENGs. The possible impact of incorporation of such properties on the TENG output is explained. An attempt has been made to chart the progress in developing such functional TENGs and point out the issues yet to be addressed in this area.