VO₂-SiO₂ Nano-Hybrid Particles by Nano-Coating on Monodispersed SiO₂ Particles

Abstract

VO₂ exhibits a metal–semiconductor transition at about 341 K, and the transition is associated with abrupt changes in optical and electrical properties. Therefore, VO₂ is very promising for a thermochromic or smart window as well as a thermister. Our final goal in this study is to prepare VO₂/SiO₂ nano hybrid materials for smart window systems. V₂O₅/SiO₂ nano hybrid particles were prepared by coating a nano layer of V₂O₅ onto monodispersed SiO₂ particles using modified vanadium alkoxide, followed by the annealing at 623 K for 2hrs in air. Various sizes of monodispersed V₂O₅/SiO₂ nano hybrid particles were prepared by changing the SiO₂ particles size. As a result, V₂O₅ nano layer was efficiently coated onto the SiO₂ nano particles. Homogeneous VO₂/SiO₂ monodispersed nano hybrid particles were successfully prepared by annealing the V₂O₅/SiO₂ nano hybrid particles up to 773 K for 2hr in H₂/Ar atmosphere.