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conceived the project. LZ, YH, and JZ performed molecular dynamics simulations and analyzed data. LZ and JZ wrote the paper. All authors read and approved the final manuscript.”
“Background Energy harvesting technology, capturing ambient waste energy from human movements or machinery vibrations, offers a promising solution for self-powered, wireless, and sustainable operation on various applications such as portable electronic devices, touch sensors, and implanted biosensors [1–3]. Since piezoelectric zinc oxide (ZnO) nanogenerators (NGs) were demonstrated for electric power conversion from mechanical energy in 2006 [4], they have been considered as a key technique for realizing the environment-friendly energy harvesting technology. As an external mechanical force is applied to vertically aligned ZnO nanowires or nanorods using an atomic force microscope (AFM) tip, the positive/negative potential is induced at the stretched/compressed side of ZnO, thus leading to a piezoelectric charge generation [5].