Regulating Electrostatic Discharge via Quasi‐gate Electrode for High‐Performance Direct‐current Triboelectric Nanogenerators

ABSTRACT Direct‐current triboelectric nanogenerators (DC‐TENGs) are promising for mechanical energy harvesting but are often hindered by incomplete charge collection and parasitic discharge pathways. Herein, inspired by the operating characteristics of depletion‐mode field‐effect transistors, we propose a quasi‐gate‐electrode enhanced DC‐TENG (QGED‐TENG). The QGED‐TENG employs a back‐side quasi‐gate‐electrode (QGE) and porous polytetrafluoroethylene film to modulate electrostatic breakdown and charge leakage, thereby effectively suppressing parasitic discharge. The QGED‐TENG enables direction‐contingent enhancement and depletion modes without external bias, notably delivering a 1.41‐fold output charge increase in enhancement mode compared to the device without the QGE. Furthermore, by leveraging redistributed electric fields and parallel discharge pathways, the multi‐unit architecture achieves a linear charge increase relative to the number of units. Benefiting from the synergistic effects of electrostatic breakdown, charge leakage, and electric field redistribution within the multi‐unit configuration, an optimized rotational QGED‐TENG achieved an ultrahigh average power density of 25 W m −2 Hz −1 and an output charge density of 13.65 mC m −2 at 60 rpm, setting a new benchmark for the porous triboelectric layer of electrostatic breakdown‐based DC‐TENGs. This work provides new physical insights and a general design strategy for maximizing spatial charge utilization and enabling high output performance DC‐TENG.