Influence of the B-site cation nature on dielectric properties of Ca2XBiO6 (X = Dy, Fe, Al) double perovskite

For the synthesis of Ca₂XBiO₆ (X = Dy, Fe, Al) metal oxides with ordered double-perovskite structure, the sol-gel auto-combustion method has been used for the first time. The synthesis progress was followed by the Fourier transform infrared spectroscopy and the samples structure was investigated by X-ray diffraction. The samples morphology was studied by means of scanning electron microscopy. The influence of the nature of the trivalent B-site cation on the dielectric properties was evaluated by resistivity measurements in vacuum at frequencies between 10²–10⁵ Hz. The best dielectric behavior was obtained for Ca₂AlBiO₆ and Ca₂DyBiO₆, while the best semiconductor behavior was found for Ca₂FeBiO₆.