掺钼对二氧化钒薄膜热致变色特性的影响

通过溶胶-凝胶和真空热处理工艺在石英基底上制备出不同掺Mo量的二氧化钒薄膜。对薄膜进行了X射线衍射及热分析,并测试了其电阻及7.5~14μm波段红外热图随温度的变化,研究了Mo掺杂对二氧化钒薄膜热致变色性能的影响。结果表明,Mo进入VO2晶格,替换了部分V的位置;随着掺Mo量的不断增加,相变温度不断降低,但电阻突变量级比未掺杂时有所减小;掺Mo量(MoO3:V2O5,下同)为5%时,相变温度可降至45℃左右;红外热图分析表明,Mo掺杂VO2薄膜的7.5~14μm波段发射率可在较低温度下突变降低,薄膜在温度增加时可在较低温度水平上主动控制自身辐射强度、降低其辐射温度。

Effects of Mo Doping on Thermochromic Properties of Vanadium Dioxide Thin Films

The Mo doped VO2 thin films were prepared by inorganic sol-gel process and vaccum post-annealing treatment on the fused-quartz substrates. The films were analysed by X-ray diffraction (XRD) and differential scanning calorimetry (DSC). The resistance-temperature property and 7.5-14 μm infrared thermochromic property were tested, and the effects of Mo doping on the thermochromic properties of VO2 thin films were studied. The results show that the Mo atoms enter the crystal lattice of VO2 and substitute some V atoms, and the temperature of phase transition decreases gradually with the increase of doping concentration. But the contrast of electrical resistance decreases compared to the undoped VO2 thin film. When the Mo doping level is 5%(wt.%, MoO3:V2O5 ), the phase transition temperature is 45 ℃. The infrared thermal images show that the Mo doping VO2 thin film can control its 7.5-14 μm infrared radiation intensity actively and lower its radiation temperature at a lower temperature level when the real temperature increases.