The cubic sodium tungsten bronzes, Na_xWO_3(x=0.854 and 0.814)were prepared by rare earths gaseous permeation method. Structural analysis was carried out by Rietveld method from powder X-ray diffraction data. The X-ra...The cubic sodium tungsten bronzes, Na_xWO_3(x=0.854 and 0.814)were prepared by rare earths gaseous permeation method. Structural analysis was carried out by Rietveld method from powder X-ray diffraction data. The X-ray diffraction profile calculated with cubic P32 models are in good agreement with the observed X-ray diffraction patterns. There is only a little difference in W-O bond and Na-O bond between Na_(0.854)WO_3 and Na_(0.814)WO_3. Conductivity measurements indicate that Na_xWO_3 show anomalous semiconducting behavior and percolation model was used to interpret it.展开更多
文摘The cubic sodium tungsten bronzes, Na_xWO_3(x=0.854 and 0.814)were prepared by rare earths gaseous permeation method. Structural analysis was carried out by Rietveld method from powder X-ray diffraction data. The X-ray diffraction profile calculated with cubic P32 models are in good agreement with the observed X-ray diffraction patterns. There is only a little difference in W-O bond and Na-O bond between Na_(0.854)WO_3 and Na_(0.814)WO_3. Conductivity measurements indicate that Na_xWO_3 show anomalous semiconducting behavior and percolation model was used to interpret it.