Recent Progress in Self-powered Graphene-Based Triboelectric Nanogenerators

Nowadays, resources of fossil fuels cause growing problems such as environmental pollution and global warming. Therefore, replacing renewable energy sources, such as thermal, nuclear, solar, and mechanical energy, has attracted worldwide attention. Piezoelectric nanogenerators, converting mechanical energy to electrical energy using the piezoelectric effect, are attractive for renewable energy. However, they have some drawbacks, such as low electrical performance, low efficiency, and limited materials to select. Since introducing triboelectric nanogenerators (TENGs) in 2012 by Wang, harvesting mechanical energy from water, wind, and human body motion using TENGs has received more interest due to their unique features, including high electrical output, low weight, and high efficiency. Besides, a wide variety of materials, including polymers, metals, and carbon materials, have been applied in TENGs to enhance their performance. Graphene is a proper selection for TENGs because of its outstanding properties, such as high specific surface area, electrical conductivity, mechanical strength, and flexibility. This paper reviews recent progress in the fabrication, performance, and application of graphene-based TENGs. Moreover, current challenges and perspectives for research work will be highlighted.