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arXiv · 2401.02348

Physical origin of enhanced electrical conduction in aluminum-graphene composites

K. Nepal·C. Ugwumadu·K. N. Subedi·K. Kappagantula·D. A. Drabold
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Abstract

The electronic and transport properties of aluminum-graphene composite materials were investigated using ab initio plane wave density functional theory. The interfacial structure is reported for several configurations. In some cases, the face-centered aluminum (111) surface relaxes in a nearly ideal registry with graphene, resulting in a remarkably continuous interface structure. The Kubo-Greenwood formula and space-projected conductivity were employed to study electronic conduction in aluminum single- and double-layer graphene-aluminum composite models. The electronic density of states at the Fermi level is enhanced by the graphene for certain aluminum-graphene interfaces, thus, improving electronic conductivity. In double-layer graphene composites, conductivity varies non-monotonically with temperature, showing an increase between 300-400 K at short aluminum-graphene distances, unlike the consistent decrease in single-layer composites.

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K. Nepal, C. Ugwumadu, K. N. Subedi, K. Kappagantula, D. A. Drabold. 2024-01-04. Physical origin of enhanced electrical conduction in aluminum-graphene composites. https://doi.org/10.1063/5.0195967

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