Atomic Force Microscopy - A Powerful Tool for Studying Contact Electrification

Contact electrification (CE) is a very common phenomenon in the daily life and occurs in almost all contact processes of dissimilar materials, including insulators, metals, and semiconductors. However, CE has been considered a phenomenon with negative effects for a long time until Wang et al. exploited this phenomenon to invent triboelectric nanogenerators (TENG). Atomic force microscopy (AFM) has unparalleled advantages in studying some basic scientific problems of CE phenomena, especially for study of CE mechanism at the nanoscale, thus greatly promoting the development of TENGs. Here, the research work of AFM in exploring CE mechanisms, including CE between solid and solid and CE between liquid and solid is systematically introduced. And the working mechanism of metal-semiconductor DC triboelectric nanogenerators based on C-AFM studies is also introduced. In addition, the potential utility and limitations of AFM in the future development of TENG technology, and discuss the direction of its improvement is analyzed. This review summarizes the important role of AFM technology in the development of TENG-based energy and sensor technology, and it is hoped it can provide an updated overview on the understanding of the existing challenges and opportunities, which would be useful to promote the development of TENG technologies.

Automated summary

This article systematically introduces the important role of atomic force microscopy (AFM) in studying contact electrification (CE) phenomena, especially in researching the CE mechanism at the nanoscale. In addition, the working mechanism of metal-semiconductor direct current triboelectric nanogenerators based on conductive atomic force microscopy (C-AFM) studies is also introduced. The potential utility and limitations of AFM in future TENG technology development and its improvement direction are analyzed. This review provides an updated overview and understanding of the existing challenges and opportunities, and it is hoped to contribute to the advancement of TENG technologies.