Papers by Keyword: Antimony Oxide

Abstract: The dielectric properties of Sb₂O₃-doped (Ba_0.732Sr_0.26Nd_0.008)TiO_3.004 ceramics fabricated by conventional solid state method were investigated. The structure was identified by X-ray diffraction method and scanning electron microscope was also employed to observe the surface morphologies. It is confirmed that Sb₂O₃-doped (Ba_0.732Sr_0.26Nd_0.008)TiO_3.004 ceramics exhibit perovskite structure and with increasing Sb₂O₃ content Ba₆Ti₁₇O₄₀ (space group C2/c (15) ) forms as a secondary phase. The experimental results reveal that the addition of Sb₂O₃ into (Ba_0.732Sr_0.26Nd_0.008)TiO_3.004 ceramics reduce the dielectric constant and Curie temperature due to the substitution for A/B-sites with Sb³⁺ ions. The standing voltage increases with increasing Sb₂O₃ content while the dielectric loss and resistivity initially decrease and then increase with the increase of Sb₂O₃ concentration. The temperature dependence of dielectric properties at different frequencies was studied as well. It indicates that the tetragonal-cubic phase transition peak is suppressed as the Sb₂O₃ content increases and the peak value reduces with the increase of frequency.

Abstract: A few antimony oxide-based nanostructures were successfully synthesized by a fast microwave irradiation method including orthorhombic Sb2O3 and Sb8O11Cl2 nanorods bundles, sheet-like orthorhombic and cubic Sb2O3 materials, pure orthorhombic Sb2O3 nanorod bundles. All these Sb-based nanostructures were characterized by XRD, SEM and TEM. It was found that precipitator agents and irradiation conditions played important roles in the formation of Sb2O3 based nanostructures. The electrochemical properties of Sb2O3 nanorod-bundles were also preliminarily investigated.

Abstract: The effects of thermal annealing on the electrical degradation of Sb2O3-Bi-Mn-Co-doped ZnO varistors were investigated. For samples with 0.04 mol% Sb2O3 or more, the nonlinearity index  of the voltage-current (V-I) characteristics after electrical degradation increased upon annealing. More-over, the value of  after electrical degradation was proportional to the full width at half maximum (FWHM) of the X-ray diffraction peak for Zn2.33Sb0.67O4-type spinel particles under various annealing conditions. The added Sb2O3 did not dissolve in the ZnO grains but became segregated at grain boundaries. Therefore, it is speculated that the increase in the FWHM of the spinel particles is due to an increase in the numbers of fine spinel particles at grain boundaries and triple points during annealing. Furthermore, it is suggested that the improvement in the electrical degradation upon annealing is due to a decrease in the mobility of oxide ions or Zn2+ ions owing to their being blocked by uniformly distributed fine spinel particles at grain boundaries.