Effect of Fe and Co doping on electrical and thermal properties of La0.5Ce0.5Mn1−x(Fe, Co)xO3 manganites

The effect of Fe and Co doping on structural, electrical and thermal properties of half doped La0.5Ce0.5Mn1−x(Fe, Co)xO3 is investigated. The structure of these crystallizes in to orthorhombically distorted perovskite structure. The electrical resistivity of La0.5Ce0.5MnO3 exhibits metal-semiconductor transition (TMS at ∼225 K). However, La0.5Ce0.5Mn1−xTMxO3 (TM = Fe, Co; 0.0 ≤ x ≤ 0.1) manganites show semiconducting behavior. The thermopower measurements infer hole as charge carriers and electron–magnon as well spin wave fluctuation mechanism are effective at low temperature domain and SPC model fits the observed data at high temperature. The magnetic susceptibility measurement confirms a transition from paramagnetic to ferromagnetic phase. The observed peaks in the specific heat measurements, shifts to lower temperatures and becomes progressively broader with doping of transition metals on Mn-site. The thermal conductivity is measured in the temperature range of 10–350 K with a magnitude in between 10 and 80 mW/cm K.