Tailoring nanostructured materials based on [formula omitted]-graphyne monolayers modified with Au heteroatoms for application in energy storage devices: A first principle study

Abstract

Pristine γ-graphyne (γ-GY) is a widely known two-dimensional system that has a high Li, Na, and K adsorption capacity with high energy barriers for the diffusion of such metal ions. In this work, we used dispersion-corrected density functional theory calculations to investigate the electronic effect of Au-doped γ-graphyne (GYE-Au and GY-Au) monolayers on the adsorption and diffusion of M metal-ions (M = Li, Na, and K). The nature of the electronic structure of the GYE-Au monolayers corresponds to a semi-metallic behavior. According to climbing image nudge elastic band calculations, low activation energies in the diffusion of M atoms are associated with the presence of the Au atom with respect to the γ-GY monolayer. High adsorption energy values were associated with the storage capacity of the GYE-Au monolayers. The electronic storage properties such as open circuit voltage and theoretical specific capacity were improved in the GYE-Au monolayers. This study shows that, at an atomistic level, the GYE-Au monolayers could be an excellent 2D anode material for Li, Na, and K-ion batteries.