Papers by Keyword: Bi³⁺

Abstract: Ca3(VO4)2: Eu3+, Bi3+ phosphor powders were prepared by the combustion synthesis or the solid state reaction at room temperature, respectively. The phase composition, morphology and photo-luminescence of the Ca3(VO4)2: Eu3+, Bi3+ phosphors were investigated by X-ray diffraction, scanning electron microscope, and spectrophotometry, respectively. The results show that the Ca3(VO4)2: Eu3+, Bi3+ powder prepared by the combustion synthesis is claviform, while the Ca3(VO4)2: Eu3+, Bi3+ powder directly obtained by the solid state reaction at room temperature is orbicular. The discrepancy in emission is attributed to the variation in the Eu3+ morphology of in powders.

Abstract: The effects of Bi3+ addition on the sintering performance and microstructural evolution of cordierite were analyzed in this paper. Cordierite powders were prepared by sol-gel processing. As nucleating agent, the Bi3+ additive was found to promote the phase transition from µ-cordierite to α-cordierite and decrease sintering temperatures. The effect of Bi3+ on the activation of cordierite can be attributed to the nucleation of cordierite. The doping of Bi3+ increased the expansion coefficient and dielectric constant. Too much Bi3+ will inhibit the cordierite crystallization and encourage anorthite crystallization.