Synthesis And Characterization Of Double Perovskite Ce-k-fe-mo-o Series Compounds

In this paper, a series of double Perovskite compounds CeKFexMo2-xO6(0.9≤x≤1.2), Ce1-xGdxKFeMoO6(0.05<x<0.1) and CeK1-xNaxFeMoO6(0.5≤x≤0.6) have been made by conventional reaction processing. By means of X-ray diffraction, vibrating sample magnetometer and four probe method, the crystal structure, the magnetic and electric properties are investigated. The main results of the dissertation are as follows:The structure of the series compounds belongs to monoclinic system with space group P21/n. In CeKFexMo2-xO6 series compounds, Volume of crystal cell is larger with increasing of Fe content; Impurities are decreased with the higher sinter temperature in CeKFe1.2Mo0.8O6; In A-site varies series compounds, the cell volume is reduced with the content of Gd ion increasing and with the content of Na ion decreasing.Thermal magnetization shows that transition temperature of all samples is over 300K and that the magnetic moment decreases slowly with temperature increasing. The electrical behavior belongs to semiconductor properties. The detailing analysis of electrical transport shows that the electrical transport properties of all the samples are controlled by small polaron variable range hopping model. In CeKFexMo2-xO6 series compounds, magnetic moment increases with Fe content increasing, magnetic moment of FC mode is higher than that of ZFC mode, resistance increases with Mo content decreasing; In Ce1-xGdxKFeMoO6 compounds, magnetic moment varies little with temperature, but magnetic moment of FC mode is lower than that of ZFC mode, because that Gd-4f is anti-ferromagnetic coupling with Fe-3d; In CeK1-xNaxFeMoO6, the magnetic moment varies little and magnetic moment of FC mode is higher than that of ZFC mode.