Electrical relaxation studies of solution combustion synthesized nanocrystalline Li2NiZrO4 material

A lithium-rich Li2NiZrO4 is synthesized by solution combustion technique in phase pure nanocrystalline form for the first time. The material is crystallized in the cubic structure of space group Fin (3) over barm with lattice parameter: a = 4.2457(3) angstrom and the average crystallites size is 55 nm. Nanocrystalline nature of the sample is confirmed through transmission electron microscopy. Ac electrical properties are investigated and the activation energy for cross-over frequency is less than that of conduction as evident from Almond and West formalism. The conductivity and modulus formalisms provide nearly the same activation energies for electrical relaxation of mobile ions. The frequency dependent plots of M '' and Z '' show that the electrical relaxation is non-Debye in nature. The scaling behavior of M '' and Z '' formalisms confirmed the temperature independent nature of relaxation mechanism. (C) 2012 Elsevier B.V. All rights reserved.