First-principles study on the phase transition temperature of X-doped (X = Li, Na or K) VO2
Abstract
Vanadium dioxide (VO2) is one of the most interesting thermochromic materials with a phase transition temperature of 340 K. Our first-principles calculations indicate that Li, Na or K dopants with a doping level of 1 atomic percentage could reduce the phase transition temperature of VO2 by 43 K, 49 K, 94 K, respectively. In addition, the V–V chains feature the dimerization characteristics in the Li, Na or K doped VO2(R). The calculated electronic structures and optical properties indicate that K is an appropriate doping element for VO2, since it can effectively lower the phase transition temperature as well as enhance the near-infrared absorption.