稀土气相扩渗法制备稀土钨青铜K_xLn_yWO_3及电性能

Preparation and Conductivity of Rare Earth Tungsten Bronze K_xLn_yWO_3 by Rare Earth Gas Phase Permeation

采用稀土气相扩渗法通过固-气界面反应以Keggin结构的K6[SiCoW11O39(H2O)]·13H2O为前驱体进行稀土气相扩渗。经X射线衍射分析(XRD)、差热-热重分析(TG-DTA)、X射线光电子能谱分析(XPS)和X射线能谱(EDS)分析表明:前驱体扩渗前后XRD衍射峰明显不同,扩渗后产物已无Keggin结构的特征衍射峰,生成了新的四方结构化合物K0.57La0.0062WO3和K0.59Ce0.0014WO3。DTA-TG分析表明:在空气气氛中,K0.57La0.0062WO3于600℃开始分解。导电性测试结果表明,K0.57La0.0062WO3电导率最高为2.03S·cm-1,K0.59Ce0.0014WO3电导率最高为0.0834S·cm-1。

Rare earth tungsten bronze KxLnyWO3 is synthesized by a rare earth co-permeation method using K6SiW11Co as the precursor and characterized by XRD, XPS, TG-DTA, EDS and XRF. The results show that the K6SiW11Co structure is decomposed and the new cubic compounds of K0.57La0.0062WO3 and K0.59Ce0.0014WO3 are formed during the thermal treatment. The DTA-TG analyses indicate that the K0.57La0.0062WO3 begins to disassemble at 600 ℃. The conductivity results indicate that the K0.57La0.0062WO3 has the highest conductivity of 2.03 S·cm^-1 at 246 ℃ and the conductivity of K0.59Ce0.0014WO3 is 0.0834 S·cm^-1, almost 25 times lower than the K0.57La0.0062WO3.