Electrical, Thermoelectric, and Structural Properties of La(M[sub x]Fe[sub 1−x])O[sub 3] (M=Mn, Ni, Cu)

Abstract

Electrical, thermoelectric, and structural properties were studied in transition metal ion-substituted : , , and . Structural analysis showed that a continuous series of solid solutions with no intermediate phases are forming over a wide range with substitutions of Mn and Ni, whereas the maximum Cu content is 30% from this study. The Ni-substituted specimens have substantially higher conductivity than those substituted with either Mn or Cu, measured in air from . The Seebeck coefficient of and has a strong temperature dependence, indicating a thermally activated carrier formation. The activation energy for carrier formation in is greater than that in . Thermoelectric and electrical properties evidence conduction through polaron hopping in both Mn- and Cu-substituted , whereas the Ni-substituted shows metallic conductivity.