Preparation and electric properties of La-doped-(Sr,Ba)TiO3 from sol-gel process

La-doped-(SrxBa1-x)TiO3 (La-0.003(SrxBa1-x)(0.997)TiO3) powders were prepared by sol-gel process. The crystallization of La-0.003(SrxBa1-x)(0.997)TiO3 was studied by means of XRD and DTA. The results showed that the perovskite phase was formed at 600 degrees C. The lattice parameters of the samples with different composition were measured at room temperature. The lattice constant and density decreased with increasing of x value in La-0.003(SrxBa1-x)(0.997)TiO3. The La-0.003(SrxBa1-x)(0.997)TiO3 sample achieved the lowest resistivity among all samples. The Curie temperatures (Tc) of La-0.003(SrxBa1-x)(0.997)TiO3 derived from dielectric constant - temperature curves decrease with increasing of x value. Voltage-current (V-T) property of the samples sintered at 1300 degrees C was measured by using HP4140B picoameter. Samples with lowest resistivity showed very good nonlinear V-I property. La0.003(SrxBa1-x)(0.997)TiO3 may be a potential candidate as varistor materials.