Boosting performance of triboelectric nanogenerator via mechanical field-effect modulation

Triboelectric nanogenerators (TENGs) are generally regarded as being fundamentally limited by their attainable surface charge density, which constrains their power output and energy conversion efficiency. This work indicates that this constraint originates from the absence of internal field-effect regulation rather than from an intrinsic electrostatic bound. A field-effect–modulated triboelectric nanogenerator (F-TENG) is presented, in which a mechanically gated electrostatic architecture is introduced on the negative triboelectric side using a floating electrode separated by a dielectric layer. A self-consistent electrostatic model reveals that mechanical separation induces an effective gate voltage through capacitive coupling, generating an auxiliary electric field that enables edge-field-assisted electron injection beyond conventional triboelectric equilibrium. This mechanism establishes a one-to-one correspondence between the F-TENG and a metal–oxide–semiconductor field-effect transistor, yielding a complete transfer characteristic consisting of triboelectric-dominated, field-effect-enhanced, and saturation regimes. Experimentally, the F-TENG exhibits a transferred charge enhancement of ~203% and a short-circuit current enhancement of ~255% compared with conventional TENGs. Correspondingly, peak power, average power, and harvested energy are enhanced by up to 545%, 613%, and 611%, respectively, together with robust direct-current output capability and long-term operational stability. These results establish TENGs as mechanically gated electrostatic energy conversion systems and redefine the physical origin and achievable limit of triboelectric surface charge density. A mechanically gated field-effect architecture is introduced into triboelectric nanogenerators to actively regulate surface charge density. Through capacitive coupling and field-effect–assisted charge injection, the device exhibits a MOSFET-like transfer characteristic and significantly enhanced charge, power, and energy output, redefining triboelectric nanogenerators as mechanically gated electrostatic energy conversion systems. • TENGs are redefined as mechanically gated electrostatic energy converters. • A MOSFET-like transfer characteristic is established for triboelectric systems. • Field-effect modulation enables charge densities beyond conventional limits.