水热合成W掺杂VO_2纳米粉体的研究

Hydrothermal synthesis and characterization of W-doped VO_2 nano-particles

VO2是一种良好的热敏材料,它在68℃可以发生从低温半导体单斜晶相VO2(M)到高温金属导体相VO2(R)的可逆转变,这种相变导致VO2的电、磁和光学性质会发生突变。在水热条件下,以草酸、钨酸和V2O5为原料制备了W掺杂VO2(B)纳米粉体,经过热处理VO2(B)可以转变为具有相变特性的VO2(M),利用XRD、SEM、DSC等手段对掺杂的产物VO2(B)和VO2(M)进行了表征。结果表明利用此方法制备的VO2为均匀的纳米晶须,平均长度约4μm。DSC结果表明VO2相变温度可以被降低,当W掺杂量为2.59%时,掺杂VO2(M)相变温度可以降低到52.1℃。

Vanadium dioxide （VO2） is an ideal thermosensitive material, it has semiconductor- metal transition at 68 ℃ accompanied by a structural transformation between a low temperature monoclinic phase VO2（M） and a high-temperature tetmgonal phase VO2（R）. Its electrical, magnetic and optical properties can change greatly. In this paper, Tungsten （W）-doped VO2（M） particles were successfully synthesized by thermal calcining of VO2（B） particles which were prepared by hydrothermal reaction of oxalic acid, tungstic acid and V2O5. The products were characterized by XRD, SEM and DSC analysis. The results show that the products are monoelinic B phase VO2 nanorods and they are about 4 μm in length. DSC analyses displayed that the critical phase transition temperature of VO2（M） particles could be reduced. When 2.59 % W^6＋ was doped into VO2, the phase transition temperature was reduced to 52.1 ℃.