Chain Model of Charge Transfer and Application to Contact Electrification

Contact electrification refers to the motion of charges through friction or even the contact between two materials. Electron transfer models seem to be good candidates for understanding the charge transfer process. This topic is closely related to explanations of static electricity as well as lightning during thunderstorms, sandstorms, and volcanic plumes. A better understanding of contact electrification should help meet future population power needs. Here we work with a previously introduced quantum mechanical chain model of contact electrification and study the charge transfer on a single chain with analytical results. The model is amenable to study the charge dynamics for a chain of atoms with symmetric and asymmetric hopping. Analytic and numeric results are shown to give rise to similar dynamics in both the absence and presence of electron interactions. We extend the chain model to the case of two atoms per cell (a perfect alloy system) and further apply it to contact electrification between two materials. The effect of increasing the magnitude of the contact transfer matrix element is studied.