Characterization of Monovacancy Defects in Vanadium Diselenide Monolayer: A DFT Study

Abstract

Defects are an integral part of the structure of various two-dimensional materials (2D), including 2D transition-metal dichalcogenides. These defects usually govern their electronic properties. In this work, simulations based on the density functional theory are employed for a comprehensive characterization of typical point defects in the T–VSe2 and H–VSe2 monolayers. Specifically, Se and V monovacancy defects are studied. The formation of monovacancies in T–VSe2 and H–VSe2 monolayers are found to be less favorable than in other common transition-metal dichalcogenides. Meanwhile, Se and V monovacancy defects tune the electronic structure of the T–VSe2 and H–VSe2 monolayers significantly. The scanning tunneling microscopy simulated images obtained could facilitate the detection of monovacancies in T–VSe2 and H–VSe2 monolayers in experiments.

Keywords

• DFT
• electronic properties
• STM
• monovacancy
• migration barrier