EPR AND MIXED IONIC-ELECTRONIC CONDUCTIVITY STUDIES OF PURE AND COPPER DOPED LAYERED LITHIUM SODIUM TITANATE (LiNa)Ti3O7

Abstract

Sodium (50%) mixed layered Li2Ti3O7 and its 0.01, 0.05 & 1.0 molar percentage CuO doped derivatives have been prepared through high temperature solid state reaction and characterized through X- ray diffractometer, d.c. conductivity in the temperature range 373–700K and room temperature EPR investigation. Room temperature X-ray diffratograms confirm the phase evolution. Room temperature electron paramagnetic resonance (EPR) data show that Cu2+ occupies Ti4+ lattice sites giving rise to electric dipoles which increases electric permittivity. The absorption peak in EPR spectra gets broadened due to increased exchange interaction in heavily doped derivatives. Four distinct regions have been identified in the Ln(σT) versus 1000/T plots. Various electrical conduction mechanisms have involved during the whole temperature range of study