Decoration of graphene nanoribbons by $5d$ transition-metal elements

TL;DR

This paper explores how decorating graphene nanoribbons with 5d transition-metal elements affects their structure, electronic, and optical properties, potentially enabling tunable nanoelectronic applications.

Contribution

It introduces the novel approach of using 5d transition-metal elements as edge passivation in graphene nanoribbons to modify their properties.

Findings

Edge decoration alters electronic band structures.

Optical transition characteristics are significantly affected.

Charge distribution is influenced by transition-metal decoration.

Abstract

Graphene is a famous truly two-dimensional (2D) material, possessing a cone-like energy structure near the Fermi level and treated as a gapless semiconductor. Its unique properties trigger researchers to find applications of it. The gapless feature shrinks the development of graphene nanoelectronics. Making one-dimensional (1D) strips of graphene nanoribbons (GNRs) could be one of the promising routes to modulating the electronic and optical properties of graphene. The electronic and optical properties of GNRs are highly sensitive to the edge and width. The tunability in electronic and optical properties further implies the possibilities of GNR application. However, the dangling bonds at ribbon edges remain an open question in GNR systems. Various passivation at the ribbon edge might change the essential physical properties. In this work, $5d$ transition-metal elements are considered as the guest atoms at the edges. The geometric structure, energy bands, density of states, charge distribution, and optical transitions are discussed.