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A series of co-doped TiO2 ceramics named (Re0.5Nb0.5)0.005Ti0.995O2 (Re = La, Nd, Sm, Gd) were prepared by a solid-state reaction method. The microstructure, dielectric properties, and impedance spectra of (Re0.5Nb0.5)0.005Ti0.995O2 ceramics were systematically investigated in detail. The co-doped TiO2 with rutile structure ceramics possessing CP and low dielectric loss (<0.05) have been gotten. Low dielectric loss is attributed to enhancing grain boundary resistance and suppressing Maxwell–Wagner polarization This work maybe give us enlightenment about how to find low dielectric loss in co-doped TiO2 CP ceramics. [ABSTRACT FROM AUTHOR]

(Pb0.87Ba0.10La0.02)(Zr0.60Sn0.40-xTix)O3(PLBZST) (x = 0–0.20) bulk ceramics were prepared by the conventional solid state method, and the dependence of phase transformation, ferroelectric properties and energy storage properties on x values has been investigated. When x = 0.12, the unit cell volume significant change indicted the phase transformation of the ceramics. As x = 0.04–0.10, the PLBZST ceramics possess anti-ferroelectric phase with high recoverable energy storage density 0.8–1.3 j/cm3and when x = 0.12–0.20, the ceramics with ferroelectric phase have lower density values about 0.2–0.3 j/cm3. The phase switching electric field, saturation polarization and test temperature have an important influence on energy storage density and efficiency. As a result, the PLBZST bulk ceramics exhibit the largest recoverable energy density of 1.3 j/cm3with efficiency of 77.4% at 20°C. [ABSTRACT FROM AUTHOR]

Li2MgTiO4ceramics were prepared with Li2CO3, TiO2and MgO by high energy ball mill method. After mixtures ball-milling 30 h and calcining at 700°C, the homogenate Li2MgTiO4powders with average particle size of 160 nm were obtained. The pure phase obtained temperature was about 300°C lower than that by a conventional solid-state reaction process. Due to Li+evaporation, the Li2MgTiO4ceramics sintered at high temperature existed with some Mg2TiO4. The Li2MgTiO4ceramics at 1250°C had an excellent microwave dielectric propertiesϵr= 12.17, Q × f = 42000 GHz and an τf= −23 ppm/°C [ABSTRACT FROM AUTHOR]

The CdWO4compound was prepared from CdO and WO3mixtures by high energy ball milling method and its microwave dielectric properties have been investigated. After milling 30 h, pure and well-crystallized CdWO4powders with an average grain size of 230 nm were obtained at 125°C. The CdWO4ceramics sintered at 950–1100°C have monoclinic structure belong to the space group P2/c(13), and when sintered at 1025°C, the ceramics exhibited good dielectric constant (ϵr) of ∼ 12.81,Q×fof ∼27000 GHz and τfof ∼−19.3 ppm/°C. [ABSTRACT FROM AUTHOR]