Physical origin of enhanced electrical conduction in aluminum-graphene composites

• Published in: Applied physics letters Vol. 124; no. 9
• Main Authors: Nepal, K., Ugwumadu, C., Subedi, K. N., Kappagantula, K., Drabold, D. A.
• Format: Journal Article
• Language: English
• Published: Melville American Institute of Physics 26-02-2024; American Institute of Physics (AIP)
• Subjects: Aluminum; Composite materials; Density functional theory; Density functional theory (DFT); Electrical conduction; enhanced conductivity; Graphene; Graphical user interface; MATERIALS SCIENCE; Plane waves; Transport properties
• ISSN: 0003-6951; 1077-3118
• DOI: 10.1063/5.0195967

The electronic and transport properties of aluminum-graphene composite materials were investigated using the 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 and 400 K at short aluminum-graphene distances, unlike the consistent decrease in single-layer composites.