Atomic and electronic structures of thermochromic VO2 with Sb-doping

Abstract

Vanadium dioxide (VO2) is an attractive transition metal oxide owing to its intriguing metal to insulator phase transition and has great potential for applications in smart windows. In this paper, first-principles calculations were conducted and the results revealed that Sb is as an efficient dopant in improving the thermochromic properties of VO2 by lowering the phase transition temperature and enhancing the transmission of visible light, as well as increasing the near-IR absorption of VO2. These changes in the optical properties of VO2 are closely correlated with the variations in the atomic and electronic structures, where the VV chains along the [001] direction present dimerization features in VO2(R) with Sb-doping; in addition, the OV bonds appear less ionic due to the OSb ionic bonds. The calculation results are confirmed by the subsequent experiments, suggesting that our findings would be useful for further understanding the physics of atomic doping in VO2, which may provide useful guidance for the fabrication of high-quality VO2 based smart windows.