Electrical transport in onion-like carbon - PMMA nanocomposites

Claudio Grimaldi; Egon Kecsenovity; Maryam Majidian; Vladimir L. Kuznetsov; Arnaud Magrez; László Forró

doi:10.1063/1.5085936

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arXiv · 1903.05385

Electrical transport in onion-like carbon - PMMA nanocomposites

Claudio Grimaldi·Egon Kecsenovity·Maryam Majidian·Vladimir L. Kuznetsov·Arnaud Magrez·László Forró

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Abstract

We report electrical conductivity measurements of Polymethyl-methacrylate filled by onion-like carbon particles with primary particle size of $\approx 5$ nm. We shown that the conductivity $σ$ is exceptionally high even at very low loadings, and that its low-temperature dependence follows a Coulomb gap regime at atmospheric pressure and an activated behavior at a pressure of $2$ GPa. We interpret this finding in terms of the enhancement under the applied pressure of the effective dielectric permittivity within the aggregates of onion-like carbons, which improves the screening of the Coulomb interaction and reduces the optimal hopping distance of the electrons.

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Claudio Grimaldi, Egon Kecsenovity, Maryam Majidian, Vladimir L. Kuznetsov, Arnaud Magrez, László Forró. 2019-03-13. Electrical transport in onion-like carbon - PMMA nanocomposites. https://doi.org/10.1063/1.5085936

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