Edge chirality determination of graphene by Raman spectroscopy

TL;DR

This study demonstrates that Raman spectroscopy can reliably identify the edge chirality of graphene, distinguishing armchair from zigzag edges by analyzing the D band intensity, which is crucial for fundamental research and applications.

Contribution

It introduces a practical Raman spectroscopy method to determine graphene edge chirality based on D band intensity differences.

Findings

D band intensity is stronger at armchair edges

Raman spectroscopy reliably distinguishes edge chirality

Method aids in crystal orientation determination

Abstract

Raman imaging on the edges of single layer micromechanical cleavage graphene (MCG) was carried out. The intensity of disorder-induced Raman feature (D band at ~1350 cm-1) was found to be correlated to the edge chirality: it is stronger at the armchair edge and weaker at the zigzag edge. This shows that Raman spectroscopy is a reliable and practical method to identify the chirality of graphene edge and to help in determination of the crystal orientation. The determination of graphene chirality is critically important for fundamental study as well as for applications.