Sintering and Electrical Conductivity of La1-XSrXMnO3

The sinterability and electrical conductivity of La1-XSrXMnO3 were studied as a function of calcination temperature (500° to 1200°C), firing temperature (1200° to 1500°C), atmosphere (air or vacuum) Sr content (0≤X≤0.5), and cation deficiency. Both density and electrical conductivity increased with either decreasing calcination temperature or increasing firing temperature. Sintering in vacuum increased the density and decreased the electrical conductivity. The content of Sr, X, influenced these characteristics remarkably, The density decreased drastically with increasing X, giving the lowest value at X=0.4. On the other hand, the electrical conductivity increased with increasing X, giving the maximum value at X=0.15. The temperature dependence of the electrical conductivity of La0.85Sr0.15MnO3 was confirmed to be consistent with the small polaron hopping transport mechanism. The cation deficiency improved the sinterability of La1-XSrXMnO3 ceramics. These results indicated that the density and electrical conductivity of La1-XSrXMnO3 are largely influenced by the concentration of incorporated oxygen.