PREPARATION AND ELECTRICAL-PROPERTIES OF KCA2-XLAXNB3O10

Electron-doped layered perovskite KCa2-xLaxNb3O10 was prepared from KN bO3, Nb2O5, Nb, La2O3 and KCa2Nb3O10 at 1200 degrees C for 10 h under Ar. Essentially single-phase KCa2-xLaxNb3O10 with plate-like morpholog y was obtained with 0 less than or equal to x less than or equal to 0. 3, and lattice parameters increased with increasing x. All the La-dope d products showed semiconducting behaviour. Linear (log rho)-T relatio nships were clearly observed, but the resistivity behaviour deviates f rom the linear relationship at lower temperatures. A possible conducti on mechanism is discussed.