Electrochemical Performance of Gold Monolayers for Lithium-Ion Batteries: A First Principles Study

Being motivated by recent synthesis of a monolayer of gold, named goldene, from the nano-laminated ternary ceramic phase of Ti3AuC2, we are proposing two phases of goldene viz. goldene-I and goldene-II as anode material for Lithium-Ion batteries using first principles study. This innovative goldene-I monolayer, composed of triangular motifs of gold atoms, exhibits remarkable properties owing to its unique geometric configuration and intrinsic stability. In contrast, a theoretical structure known as goldene-II, featuring a combination of triangular and hexagonal motifs, has been proposed. This structure possesses intrinsic, periodically distributed pores among Au atoms and demonstrates structural integrity and mechanical robustness, even under lithium adsorption. The electronic band spectra and projected density of states reveal the metallic nature of both phases of goldene. Electrochemical evaluations reveal that goldene-II offers favorable lithium-ion adsorption energies, efficient charge transfer, and volumetric capacities. Goldene-I achieves a volumetric capacity of 0.713 Ah/cm3, while goldene-II reaches 0.783 Ah/cm3, confirming its high suitability for lithium storage volumetric capability. Moreover, goldene-I has an ultra-low barrier height of 15 meV, which supports rapid lithium-ion transport.