Output optimization of biodegradable triboelectric nanogenerators

The emergence of nanogenerators provides a creative way of collecting tiny energy. Biodegradable triboelectric nanogenerators (BD-TENGs) have become a hot topic in the field of green energy due to their eco-friendliness, safety, and good biocompatibility. The biggest problem in the development of BD-TENGs is how to improve their relatively low output performance. Based on major factors that have a significant impact on the power generating process during friction, including the triboelectric polarity of friction layers, frictional contact areas between them, and their charge accumulation ability, various methods to improve the output performance of BD-TENGs were developed. This review summarizes the existing optimizing methods of BD-TENGs, which can be generally divided into three groups, including the alteration of friction material compositions, the change of surface microstructures, and the promotion of dielectric properties, thus aiming at providing some ideas for future research in the field of BD-TENG.