Transport properties in non-oxide perovskite ferroelectric relaxors

Abstract

Electric transport in a Cu-doped Cd salt [(CH₂)₃(NH₃)₂Cd_{1− x} Cu _x Cl₄, x = 0.0, 0.07, 0.395 and 0.69] was investigated in the frequency range 60 Hz–100 kHz and the temperature range 290–450 K. The conductivity increases with increasing copper doping. Samples with x = 0.0 and 0.07 undergo phase transitions at 374 K and 369 K, respectively. Ferroelectric relaxor-like behaviour appears for x = 0.395 and 0.69. The conduction mechanism of the samples with x = 0.0 and 0.07 depends on the temperature region. Below the transition temperatures chlorine vacancy and proton hopping prevails, whereas above the transition temperatures mainly proton conduction dominates. Transport in the new non-oxide ferroelectric relaxors, where x = 0.395 and 0.69, can be explained by the jump relaxation model where proton and ionic hopping contribute to the conductivity throughout the whole temperature range.