Electrical Properties of Undoped and Lanthanum Doped BaTi0.6Zr0.4O3

Lanthanum doped BaTi0.6Zr0.4O3 composition x = 0.005, 0.01, 0.02, 0.05 and 0.1 in Ba1-xLaxTi0.6[1-5x/12]Zr0.4O3 were prepared by modified chemical route. (COOH)2.2H2O, Ba(NO3)2, ZrOCl2.8H2O and La2O3 are used to precipitate barium oxalate hydrate, lanthanum oxalate hydrate and zirconium oxy-hydroxide from its water solution onto the surface of suspended TiO2 particles. The lanthanum doped BaTi0.6Zr0.4O3 composition was found to be cubic by XRD analysis. A gradual shift of 2θ angles to the higher angle with increasing lanthanum percentage in the BTZ reveals the contraction of perovskite lattice. The frequency dependence of dielectric permittivity and loss tan δ of the ceramics has been investigated. It is found that dielectric permittivity (εr) decreases and loss tan δ decreases with increase in lanthanum percentage. Neither of the samples shows semiconductivity, which is believed to be because of titanium vacancy compensation.