Surface Triboelectrification of MXenes with Fluorine Groups for Flexible Energy Harvesting and Sensing

Triboelectric nanogenerator (TENG) has attracted attention for flexible electronics in the past decade. MXene is gradually applied in TENGs for performance enhancement, but the surface triboelectrification mechanism still needs to be further investigated experimentally. Herein, an experimental approach of regulating MXene fluorine groups by alkalization as a contrast to validate the mechanism is proposed. The MXene film and alkalized MXene film are studied to exploit the surface state. Compared with alkalized MXene‐based TENGs, MXene‐based TENG obtains enhancement in open‐circuit voltage, short‐circuit current, and output power by 4.1 times, 4.6 times, and even 136.6 times, respectively. The excellent performance enables flexible sensing and energy harvesting. Notably, this work reveals MXene surface triboelectrification mechanism and might motivate a new approach for TENG performance enhancement.