Thermal properties of La_0.7Ca_0.2Sr_0.1MnO₃:PdO composites

Highlights: • Thermal conductivity deceases with increase in Pd content. • Mott's polaron hopping mechanism is operative at high temperatures. • Change in entropy ΔS decreases with Pd content. - Abstract: A systematic study on the thermal conductivity, Seebeck coefficient and specific heat of La_0.7Ca_0.2Sr_0.1MnO₃:PdO composites is presented. Solid state reaction procedure was employed to synthesis the samples. It is seen from thermal conductivity (κ(T)) studies that the samples exhibit a slope change nature close to their corresponding magnetic phase transition temperature, T_C. The overall magnitude of κ is observed to decrease with increasing Pd concentration. The analysis of Seebeck coefficient data, S(T) versus temperature, T was done using Mott's polaron hopping model reveals that the electron-magnon scattering is governing the low temperature region. The temperature dependent specific heat C_P(T) is analyzed to determine the entropy change (ΔS) during the magnetic phase transition.