Quenching of the Resonant States of Single Carbon Vacancies in Graphene/Pt(111)

Abstract

For more than a decade, investigations of single carbon vacancies in graphene have sought to increase the fundamental understanding of the local electronic, magnetic, and mechanical properties of such vacancies. The single C vacancy in graphene has been known to generate a resonant state through the integration of π orbitals near the missing C atom. Here, we examine single C vacancies in graphene/Pt(111) to explore the effects of graphene–substrate interactions on the local electronic properties of imperfect graphene. Our scanning tunneling microscopy, scanning tunneling spectroscopy, and related density functional theory calculations show the resulting modifications, including the complete disappearance of the resonant state attributable to strong graphene–substrate coupling near the vacancy. The different relative positions of single C vacancies corresponding to the Pt atoms lead both to varying C–Pt bonding structures and strengths and to corresponding changes in the local density of states.