Ternary-Dielectric Dual-Domain Triboelectric Nanogenerator for High Charge Density and Tail-Charge Suppression

Abstract

Residual-charge accumulation and limited interfacial charge excitation have emerged as inherent bottlenecks that constrain the charge density and energy-conversion efficiency of sliding triboelectric nanogenerators (TENGs). These limitations commonly originate from binary-dielectric architectures, in which deep-level tail charges and incomplete interfacial depletion hinder charge transfer regardless of materials or structural configurations. Here, we introduce a ternary-dielectric dual-domain triboelectric architecture that overcomes this intrinsic constraint by reconfiguring the dielectric field landscape and enabling cross-domain charge management. The upper discharge domain-constructed by a PA/PTFE/PU ternary triboelectric layer with adjacent electrodes-realizes efficient interfacial charge generation and active removal of tail-inherent charges via corona-assisted regulation. Simultaneously, a lower polarization-discharge domain formed by promoting discharge electrodes harnesses space-volume-induced charge migration within the PU foam, converting previously lost inherent charges into additional effective output via dielectric-polarization discharge. By coupling these two charge domains, the system establishes a charge-generation and charge-depletion pathway that systematically reshapes the excitation–decay dynamics of triboelectric charges. The optimized device achieves a considerable charge density of 1.2 mC·m⁻², an average power density of 22.53 W·m⁻², and an energy density of 3.42 J·m⁻². This work introduces a generalizable dielectric-domain engineering strategy that addresses long-standing charge-retention and tail-charge bottlenecks in TENGs, offering a mechanistic foundation for next-generation high-efficiency triboelectric energy-conversion systems.