Dielectric properties of lanthanum-doped CaCu3Ti4O12 synthesized by semi-wet route

Effect of La3+ doping at Ca2+ site in CaCu3Ti4O12 has been examined. Compositions with x = 0.10, 0.20 and 0.30 were synthesized in the system Ca(1-3x/2)LaxCu3Ti4O12 by semi-wet method. Powder X-ray diffraction confirmed the formation of monophasic compounds. The structure remains cubic similar to CaCu3Ti4O12. Lattice parameter increases slightly with increasing La3+ concentration. Microstructure has been studied using scanning electron microscopy (SEM). Average grain size is in the range 2-4 mu m for various compositions. Energy-dispersive spectrometer (EDS) studies confirm the stoichiometry of the synthesized materials. Dielectric constant, dielectric loss and conductivity of the samples decrease with increasing lanthanum concentrations. (C) 2009 Elsevier Ltd. All rights reserved.