We have prepared the CuFe 1-xMn xO 2 solid solution to enhance the thermoelectric performance of CuFeO 2 by reducing its thermal conductivity κ. With increasing x above 0.4, the crystal structure changes from delafossite ( 1̄3m) to crednerite (C2/m). CuFe 0.5Mn 0.5O 2 exhibits the lowest κ value of 2.28 W/m K at the theoretical density, being about one-quarter of that of the end members, CuFeO 2 and CuMnO 2. We discuss the temperature dependence of κ in terms of a classical phonon transport model, and conclude that local structural modulation due to the mixture of undistorted FeO 6 octahedra and distorted MnO 6 octahedra in CuFe 1-xMn xO 2 leads to the significant reduction of κ.
- solid solution
- thermal conductivity
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics
- Electrical and Electronic Engineering
- Materials Chemistry