Effect of Dopants on Σ3 (111) Grain Boundary in Diamond

Abstract

In recent years, extensive research has been conducted on electronic properties of metal‐doped diamond for electrochemical applications. The co‐doped diamond has emerged as an important strategy to enhance their performance and impart novel characteristics. The present investigation employs density functional theory calculations to envisage the structural, electronic, and elastic properties of nitrogen‐ vacancy (N‐V) and silicon‐vacancy (Si‐V) defects at the Σ3 (111) grain boundary in diamond. Further, the Li and Na atoms were introduce as a dopant into these defective structures, referred as Σ3Li(N‐V), Σ3Na(N‐V), Σ3Li(Si‐V), and Σ3Na(Si‐V). The results reveal that the doped structures considered in the investigation are energetically and dynamically stable. Presence of defects (i.e., dangling bonds due to the presence of vacancies and dopants) at the Σ3 (111) grain boundary significantly alters the overall electronic property of the diamond. The adsorption energies calculated for the doped systems ranging from ‐1.2 and 8.38 eV. The Σ3Li(N‐V) shows negative adsorption energy, indicating the tendency of lithium atom to adsorb exothermic onto the grain boundary of Σ3N‐V, whereas, all other adsorptions are endothermic in nature. The choice of dopant plays a substantial role in altering properties of a diamond, while the mechanical properties of the single‐ and co‐doped Σ3 (111) diamond structures vary marginally.This article is protected by copyright. All rights reserved.