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Updated: Nov 4, 2025

Finite Element Modelling of a Cellular Electric Microenvironment
Published on: May 18, 2021
Dynamics of contact electrification
Mirco Kaponig1, Andre Mölleken1, Hermann Nienhaus1
1Faculty of Physics and Center for Nanointegration Duisburg-Essen CENIDE, University of Duisburg-Essen, Lotharstraße 1, 47057 Duisburg, Germany.
Abstract:
Although the electrical charging of objects brought into contact has been observed for at least 2000 years, the details of the underlying mechanism are still not yet fully understood. The present paper deals with the very basic process of contact electrification between two metals. We have developed an experimental method to follow the charge of a small sphere bouncing on a grounded planar electrode on a time scale down to 1 μs. It reveals that the sphere is discharged in the moment of contact, which lasts about 6 to 8 μs. However, at the very moment of disruption of the electrical contact, it regains charge far beyond the expectation according to the contact potential difference. The excess charge rises with increasing contact area.
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