Structural Characterization, Stability And Electrical Properties Of Strontium Niobate Ceramic

摘要

The double perovskite oxide Sr_2CrNbO_6 has a cubic structure according to powder X-ray diffraction. After reducing in CO, Sr_2CrNbO_6 still exhibited a cubic structure refined by Rietveld technique. The TG analysis indicated that Sr_2CrNbO_6 loses 0.127 oxygen per formula unit from 400 to 700℃ in H_2. The morphology and compositions of this ceramic did not significantly change on reduction. The conductivities in various atmospheres were varied from 0.015 to 0.039 S cm~(-1) at 800℃. The conductivity exhibits a small oxygen partial pressure dependence in oxygen partial pressure range of 1 -10~(-16) atm, and this may be interpreted to reflect slow equilibration kinetics with decreasing oxygen activity.