Tuning the phase transition temperature, electrical and optical properties of VO 2 by oxygen nonstoichiometry: insights from first-principles calculations

The O-vacancy in bulk VO 2 gives rise to an increase in electron concentration, which induces a decrease in T c . While, O-vacancy and O-adsorption on VO 2 (R) (1 1 0) and VO 2 (M) (0 1 1) surfaces could alter the work functions and in turn regulate T c .