The electron transfer dynamics in the contact electrification and its effects on the intensity of triboluminescence

TL;DR

This paper investigates the electron transfer mechanisms in contact electrification of insulators using triboluminescence observations and proposes a capacitor model emphasizing electron tunneling driven by contact potential difference.

Contribution

It introduces a theoretical capacitor model for insulator contact electrification, highlighting electron tunneling as the dominant charge transfer mechanism, supported by experimental triboluminescence data.

Findings

Electron tunneling is the main mechanism in insulator contact electrification.

The capacitor model accurately predicts charge transfer dynamics.

Experimental results support the model's assumptions.

Abstract

With the growing threat of energy crisis and the increasing need to power microelectronic devices, people are seeking potential alternative energies that can replace the conventional sources such as fossil fuels. Due to its simple structure, low cost, and high performance, the triboelectric nanogenerator (TENG) which is based on the contact electrification has become one of the most promising candidates. Although plays a crucial role in determining the amount of charge transfer of TENG, the fundamental mechanism that underlies the charge transfer in the contact electrification of insulator-insulator contacts has still not been completely understood. In this paper, the dynamics of charge transfer in the contact electrification is investigated by observing the triboluminescence of the sliding contacts and a theoretical model is proposed for the electrification of insulator-insulator contacts. In the present "Capacitor model", the electron tunneling is assumed to be the dominating mechanism in the electrification and the driving force for the electron transfer is the contact potential difference, and thus, the electrification is considered as a charging process of the capacitor formed by the contact surfaces. The consistency between the predictions by the present model and the experiments may confirm again that the electron transfer is the dominant process in the contact electrification of insulator-insulator contacts.