Chemical Functionalization of Graphene Nanoribbons by Carboxyl Groups on Stone-Wales Defects

TL;DR

This study uses density functional theory to show that attaching carboxyl groups to Stone-Wales defects in graphene nanoribbons significantly alters their electronic properties, potentially enabling new sensor and nanoelectronic applications.

Contribution

It demonstrates the chemical functionalization of GNRs with COOH groups at SW defects and explores the resulting electronic property changes, including a transition from semiconducting to metallic behavior.

Findings

Electrical conductivity is enhanced by COOH adsorption.

System transitions from semiconducting to p-type metallic with more SW defects.

GNRs could be used in chemical sensors and nanoelectronics.

Abstract

Using the density functional theory, we have demonstrated the chemical functionalization of semiconducting graphene nanoribbons (GNRs) with Stone-Wales (SW) defects by carboxyl (COOH) groups. It is found that the geometrical structures and electronic properties of the GNRs changed significantly, and the electrical conductivity of the system could be considerably enhanced by mono-adsorption and double-adsorption of COOH, which sensitively depends upon the axial concentration of SW defects COOH pairs (SWDCPs). With the increase of the axial concentration of SWDCPs, the system would transform from semiconducting behavior to p-type metallic behavior. This fact makes GNRs a possible candidate for chemical sensors and nanoelectronic devices based on graphene nanoribbons.