Study on the Growth of Monoclinic VO₂ Phase Applicable for Thermochromic Ceramic Tile

Abstract

Vanadium dioxide (VO 2) of monoclinic phase exhibits Metal Insulator Phase Transition (MIPT) phenomenon involving a sharp change in electrical and optical properties at 68 o C. Solution-based process is applied to form uniform VO 2 coating layer on ceramic tiles. This can selectively block the near-infrared light to possibly reduce the energy loss and prevent dew condensation caused by the temperature difference. Heat treatment conditions including temperature and dwell time were examined to obtain a monoclinic VO 2 single phase. Both rutile and monoclinic VO 2 phases were observed from in the tiles post-annealed below 700 o C. Desired monoclinic VO 2 single phase was grown in the tiles heat treated at 750 o C. Nano facets of irregular size were observed in the monoclinic VO 2 phase involving the phase-transition. Grain growth of monoclinic VO 2 phase was observed as a function of dwell time at 750 o C.