Synthesis and electrical properties of (LiCo3/5Fe1/5Mn1/5)VO4 ceramics

(LiCo3/5Fe1/5Mn1/5)VO4 ceramic was synthesized via solution-based chemical method. X-ray diffraction analysis was carried out on the synthesized powder sample at room temperature, which confirms the orthorhombic structure with the lattice parameters of a = 10.3646 (20) angstrom, b = 3.7926 (20) angstrom, c = 9.2131 (20) angstrom. Field emission scanning electron microscopic analysis was carried out on the sintered pellet sample that indicates grains of unequal sizes (similar to 0.1 to 2 mu m) presents average grains size with polydisperse distribution on the surface of the ceramic. Complex impedance spectroscopy (CIS) technique is used for the study of electrical properties. CIS analysis identifies: (i) grain interior, grain boundary and electrode-material interface contributions to electrical response (ii) the presence of temperature dependent electrical relaxation phenomena in the ceramics. Detailed conductivity study indicates that electrical conduction in the material is a thermally activated process. The variation of A.C. conductivity with frequency at different temperatures obeys Jonscher's universal law. (C) 2009 Elsevier Masson SAS. All rights reserved.