Effects of electron doping on the structure and magnetic properties in Ca2−xCexFeMoO6 double perovskites

Abstract

A sol–gel method has been used to prepare a series of polycrystalline Ca 2− x Ce x FeMoO 6 ( x = 0–0.4) double perovskites. Rietveld refinement of X-ray diffraction data indicates that although cell parameters increase slightly, the symmetry of the crystalline structure is preserved upon Ce doping. The partial substitution of Ce 3+ for Ca 2+ reduces the saturation magnetization, however it considerably enhances the Curie temperature ( T C ) from 365 K for x = 0 to 393 K for x = 0.4. Transport measurement shows that Ca 2− x Ce x FeMoO 6 exhibits metallic behavior, and the resistivity of Ca 2− x Ce x FeMoO 6 increases first, and then decreases with the increasing of x . The behavior of the increasing of T C and the decreasing of resistivity upon Ce doping was explained by the electron doping effects.