Structural, chemical and dynamical trends in graphene grain boundaries

TL;DR

This paper investigates general trends in the structural, chemical, and dynamical properties of graphene grain boundaries using computational methods, revealing how these properties vary with lattice mismatch and supporting findings with experimental data.

Contribution

It provides a comprehensive analysis of trends in graphene grain boundaries, linking structural, chemical, and dynamical properties as functions of lattice mismatch, which was not previously systematically studied.

Findings

Energy varies with lattice mismatch.

Polygon composition correlates with boundary structure.

Chemical reactivity and vibrational properties show consistent trends.

Abstract

Grain boundaries are topological defects that often have a disordered character. Disorder implies that understanding general trends is more important than accurate investigations of individual grain boundaries. Here we present trends in the grain boundaries of graphene. We use density-functional tight-binding method to calculate trends in energy, atomic structure (polygon composition), chemical reactivity (dangling bond density), corrugation heights (inflection angles), and dynamical properties (vibrations), as a function of lattice orientation mismatch. The observed trends and their mutual interrelations are plausibly explained by structure, and supported by past experiments.