Atomistic Field Theory for contact electrification of dielectrics

TL;DR

This paper introduces an Atomistic Field Theory approach to understand contact electrification in dielectrics, focusing on surface lattice deformations and polarization fields, providing insights into triboelectric phenomena.

Contribution

It develops a novel AFT-based model to simulate surface polarization and electric fields in dielectric contact electrification, bridging a gap in theoretical understanding.

Findings

Simulation shows MgO/BaTiO3 can generate up to 10^4 V/cm^2

The model explains surface dipole formation due to lattice deformation

Results align with experimental data in literature

Abstract

The triboelectrification of conducting materials can be explained by electron transfer between different Fermi levels. However, triboelectrification in dielectrics is poorly understood. The surface dipole formations are shown to be caused by the contact-induced surface lattice deformations. An Atomistic Field Theory (AFT) based formulation is utilized to calculate the distribution of the polarization, electric and potential fields. The induced fields are considered as the driving force for charge transfer. The simulation results show that a MgO/BaTiO3 tribopair can generate up to 104 V/cm^2, which is comprable with the data in the published literature.