“…Following this initial discovery, both direct current [23,499,500] and alternating current [24] ZnO nanogenerators have been developed. In addition, nanogenerators based on other materials, such as GaN nanowires [501][502][503], InN nanowires [504], AlGaN nanocones [505], CdS nanowires [506], ZnO/ZnS heterojunction nanowires [507], lead zircornia titanates (PZT) nanofibers [508], nanoribbons [509][510][511][512][513], nanotubes [514], and single crystalline nanowires [515], BaTiO 3 nanowires [516], NaNbO 3 nanowires [517], and poly(vinylidene fluoride) (PVDF) nanofibers [518,519], have shown promising potential for enhancing nanogenerator performance. Consequently, a worldwide effort has been launched in this regard, forming a new research field in nanotechnology and energy science [520].…”