| 초록 |
Vanadium dioxide(VO2) has attracted much attention because its semiconductor-to-metal(S-M) transition temperature(Tc) is near room temperature(68℃), which makes it useful for application to optical switching devices and intelligent energy conserving windows coating. The decrease of transition temperature can be attributed to tungsten-doped vanadium dioxide and induced by W atoms that leads to the loss of V4+-V4+ pairs and destabilizes the semiconductor phase and consequently lowers the S-M transition temperature. In synthesizing of W-VO2, the reaction can be occurred unexpectedly at room temperature because VO2 have various valence numbers such as V5+, V4+, V3+ and V2+. We investigated to prepare W-VO2 particle at low reaction temperature(10℃) in order to reproductive synthesis. The transition temperatures are appeared mostly at similar temperature repeatedly. XRD patterns indicated that all W-doped VO2 particles were monoclinic crystals. DSC analyses displayed that W-doped VO2 particles had good phase transition characteristic around 40℃. For further characterization, TEM, FE-SEM and XPS analysis were done. |
