Effect of strontium substitution on electrical conduction properties of Ba5DyTi3V7O30
Strontium-substituted barium vanadates, Ba 5- x Sr x DyTi 3 V 7 O 30 ( x = 0–5), were prepared by a high-temperature sold-state reaction method. The formation of the materials was checked by X-ray diffraction technique. Preliminary structural analyses of the materials exhibit the formation of new compounds in orthorhombic structure. Surface morphology of the compounds was studied by scanning electron microscopy. The effect of Sr on microstructure of the materials has resulted in a modification of the electrical properties. Study of electrical properties using impedance analysis technique exhibit (i) the presence of negative temperature coefficient of resistance behavior, (ii) presence of temperature dependent electrical relaxation phenomena, (iii) evidences of single electrical relaxation attributed to the presence of bulk contribution to the electrical properties, (iv) an enhancement in the barrier to the mobility of charge carriers on Sr-substitution. The effects of Sr in the electrical conductivity as a function of temperature at different frequency are explained in impedance spectrum analyses.