Effects of (Mg1/3Sb2/3)4+ substitution on the structure and microwave dielectric properties of Ce2Zr3(MoO4)9 ceramics

Ce-2[Zr1-x(Mg1/3Sb2/3)x](3)(MoO4)(9) (0.02 <= x <= 0.10) ceramics were prepared by the traditional solid-state method. A single phase, belonging to the space group of R (3) over barc, was detected by using X-ray diffraction at the sintering temperatures ranging from 700 to 850 degrees C. The microstructures of samples were examined by applying scanning electron microscopy (SEM). The crystal structure refinement of these samples was investigated in detail by performing the Rietveld refinement method. The intrinsic properties were calculated and explored via far-infrared reflectivity spectroscopy. The correlations between the chemical bond parameters and microwave dielectric properties were calculated and analyzed by Phillips-van Vechten-Levine (P-V-L) theory. Ce-2[Zr-0.94(Mg1/3Sb2/3)(0.06)](3)(MoO4)(9) ceramics with excellent dielectric properties were sintered at 725 degrees C for 6 h (epsilon(r) = 10.37, Qxf = 71,748 GHz, and tau(f) = -13.6 ppm/degrees C, epsilon(r) is the dielectric constant, Qxf is the quality factor, and tf is the temperature coefficient of resonant frequency).