Preparation and thermochromic property of tungsten-doped vanadium dioxide particles

Tungsten (W)-doped vanadium dioxide (VO2) particles were successfully synthesized by hydrolysis of vanadyl sulfate mingled with a small amount of sodium tungstate dihydrate and subsequent calcination. XPS analyses demonstrated that the vanadium oxide was composed of stoichiometric VO2, and the doped W content in VO2 particles could be easily controlled by the concentration of W precursor. XRD patterns indicated that all the W-doped VO2 particles were monoclinic crystals, and the W dopant almost had no influence on the crystal structure of VO2 particles. DSC analyses displayed that the critical phase transition temperature of VO2 particles could be reduced to room temperature or even lower by increasing the doped W fraction. UV–vis–NIR spectra showed that the W-doped VO2 particles embedded acrylic coating had very good thermochromic performance.