title: Thermoelectric properties of Ca(1-x)Gd(x)MnO(3-δ) (0.00, 0.02, and 0.05) systems.
abstract: Polycrystalline samples of Ca(1-x)Gd(x)MnO(3-δ) (x = 0.00, 0.02, and 0.05) have been studied by X-ray diffraction (XRD), electrical resistivity (ρ), thermoelectric power (S), and thermal conductivity (κ). All the samples were single phase with an orthorhombic structure. The Seebeck coefficient of all the samples was negative, indicating that the predominant carriers are electrons over the entire temperature range. The iodometric titration measurements indicate that the electrical resistivity of Ca(1-x)Gd(x)MnO(3-δ) correlated well with the average valence of Mn(v+) and oxygen deficiency. Among the doped samples, Ca₀.₉₈Gd₀.₀₂MnO(3-δ) had the highest dimensionless figure of merit 0.018 at 300 K, representing an improvement of about 125% with respect to the undoped GaMnO(3-δ) sample at the same temperature.
authors.affiliation: Department of Physics, National Changhua University of Education, Changhua 500, Taiwan.
authors.forename: Ankam
authors.initials: A
authors.lastname: Bhaskar
authors.forename: Chia-Jyi
authors.initials: CJ
authors.lastname: Liu
authors.forename: J J
authors.initials: JJ
authors.lastname: Yuan
mesh_terms: D002118:Calcium / Q000737:chemistry; D055598:Chemical Phenomena; D003460:Crystallization / Q000379:methods; D017097:Electric Impedance; D004583:Electrons; D005682:Gadolinium / Q000737:chemistry*; D008345:Manganese / Q000737:chemistry; D017895:Manganese Compounds / Q000138:chemical synthesis / Q000737:chemistry*; D010100:Oxygen / Q000737:chemistry; D013696:Temperature; D013814:Thermal Conductivity; D017186:Titrimetry / Q000379:methods; D014961:X-Ray Diffraction / Q000379:methods
chemical_list: D017895:Manganese Compounds; D008345:Manganese; D005682:Gadolinium; D010100:Oxygen; D002118:Calcium