A theoretical study on synergistic tuning of graphene phonons via heteroatom modifications

Abstract

This study systematically investigates the effects of nitrogen doping, gold atom cluster loading, and their synergistic influence on the phonon dispersion relations and electronic structure of graphene, based on density-functional theory calculations. Gold atom loading induces significant changes in the low-frequency phonon modes of graphene, and affects the electronic density of states near the Fermi level, indicating strong interactions between gold d-orbitals and graphene's π-orbitals. Nitrogen doping increases the complexity of the phonon spectrum by introducing high-frequency phonon modes and modifying the electronic structure. The synergistic effect of nitrogen doping and gold atom loading results in even more intricate modifications, characterized by the emergence of low-energy phonon modes, reflecting a profound impact on both the electronic and vibrational properties of graphene. Additionally, we compare the experimental electron energy loss spectrum of single Au atom loading on graphene with the simulated spectrum, revealing a good match between them. These findings provide a theoretical basis for designing graphene-based materials with tailored properties for applications in electronic devices and catalysis, suggesting that precise regulation of these properties can be achieved through controlled doping and metal atom loading.