Towards optimized triboelectric nanogenerators

The rapid progression of electronic technologies is predicted to enhance the quality of life of the people around the world. A key challenge in achieving these targets is the need to develop sustainable power sources, which can support the ubiquitous and mobile operation of next generation electronic devices. Energy harvesting from ambient mechanical movements is seen as one of the main approaches in powering autonomous low power electronic systems such as wearables and IoT technology. Triboelectric nanogenerators (TENGs) have attracted significant attention in recent years as an emerging mechanical energy harvesting technology, due to numerous advantages over conventional mechanical energy harvesters. In this paper, we present a comprehensive review on the structural, material, motion and environmental parameters affecting the power output of triboelectric nanogenerators. The optimisation strategies for these energy harvesters are discussed, based on the theoretical and experimental studies in the literature. Finally, we discuss the major challenges in this research field, along with the future outlook.