Achieving ultrahigh triboelectric charge density for efficient energy harvesting

TLDR

Triboelectric nanogenerators, known for their lightweight, low cost, and high efficiency at low frequencies, are promising for self‑powered sensor networks and large‑scale blue energy, but their output is limited by triboelectric charge density. The study aims to increase triboelectric charge density by coupling surface triboelectrification with hysteretic dielectric polarization of a ferroelectric material in vacuum. This is achieved by integrating surface polarization from triboelectrification with ferroelectric hysteretic dielectric polarization under a vacuum pressure of ~10⁻⁶ torr. The approach yields a charge density of 1003 µC m⁻², near the dielectric breakdown limit, and demonstrates an optimization methodology that enhances triboelectric nanogenerator performance for powering devices and harvesting blue energy.

Abstract

Abstract With its light weight, low cost and high efficiency even at low operation frequency, the triboelectric nanogenerator is considered a potential solution for self-powered sensor networks and large-scale renewable blue energy. As an energy harvester, its output power density and efficiency are dictated by the triboelectric charge density. Here we report a method for increasing the triboelectric charge density by coupling surface polarization from triboelectrification and hysteretic dielectric polarization from ferroelectric material in vacuum ( P ~ 10 −6 torr). Without the constraint of air breakdown, a triboelectric charge density of 1003 µC m −2 , which is close to the limit of dielectric breakdown, is attained. Our findings establish an optimization methodology for triboelectric nanogenerators and enable their more promising usage in applications ranging from powering electronic devices to harvesting large-scale blue energy.