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arXiv · 2201.04688

Band bending and ratcheting explain triboelectricity in a flexoelectric contact diode

Karl P. Olson·Christopher A. Mizzi·Laurence D. Marks
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Abstract

Triboelectricity was recognized millennia ago, but the fundamental mechanism of charge transfer is still not understood. We have recently proposed a model where flexoelectric band bending due to local asperity contacts drives triboelectric charge transfer in non-metals. While this ab-initio model is consistent with a wide range of observed phenomena, to date there have been no quantitative analyses of the proposed band bending. In this work we use a Pt$_{\mathrm{0.8}}$Ir$_{\mathrm{0.2}}$ conductive atomic force microscope probe to simultaneously deform a Nb-doped SrTiO$_{\mathrm{3}}$ sample and collect current-bias data. The current that one expects based upon an analysis including the relevant flexoelectric band-bending for a deformed semiconductor quantitively agrees with the experiments. The analysis indicates a general ratcheting mechanism for triboelectric transfer and strong experimental evidence that flexoelectric band-bending is of fundamental importance for triboelectric contacts.

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Karl P. Olson, Christopher A. Mizzi, Laurence D. Marks. 2022-01-12. Band bending and ratcheting explain triboelectricity in a flexoelectric contact diode. https://doi.org/10.1021/acs.nanolett.2c00107

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