论文部分内容阅读
对不同球磨时间的BaCO3,CeO2和Y2O3原料粉体进行固相反应,合成了不同粒度的BaCe0.90Y0.10O3-α粉体.将其冷压成型、高温烧结后,获得了不同致密度的BaCe0.90Y0.10O3-α样品.利用激光粒度分析、差式扫描量热-热重、X射线衍射和扫描电镜技术研究了球磨时间对粉体粒度、合成过程、晶体结构及样品微观形貌的影响.结果表明:适度延长球磨时间,原料颗粒细化,BaCe0.90Y0.10O3-α的合成温度降低,合成粉体的粒度变小、分布变窄、比表面积增大,从而提高了烧结样品的致密度.利用电化学阻抗谱技术测量了原料球磨6 h和10 h的BaCe0.90Y0.10O3-α烧结样品在空气中573~1 073 K内的阻抗谱,并计算出其电导率分别为3.25×10-3~6.98×10-2S.cm-1和5.46×10-3~7.20×10-2S.cm-1.在测试温度范围内,两种样品的电导率与温度的关系符合Arrhenius方程,电导激活能分别为0.39 eV和0.34 eV.提高烧结样品的致密度是降低电导激活能,提高导电性能的有效途径.BaCe0.90Sm0.10O3-α,BaCe0.90Y0.10O3-α和BaCe0.85Y0.15O3-α的电导激活能依次降低,符合理论预测.
BaCO3, CeO2 and Y2O3 powders with different milling time were solid-state reacted to synthesize BaCe0.90Y0.10O3-α powders with different particle sizes. After cold forming and sintering at high temperature, BaCe0 .90Y0.10O3-α samples.The effect of milling time on the particle size, synthesis process, crystal structure and microstructure of the samples was studied by laser particle size analyzer, differential scanning calorimetry-thermogravimetry, X-ray diffraction and scanning electron microscopy The results show that the synthesis temperature of BaCe0.90Y0.10O3-α decreases and the particle size of the synthesized powder decreases, the distribution becomes narrower and the specific surface area increases, thus increasing the sintering time Density.The impedance spectra of BaCe0.90Y0.10O3-α sintered samples which were ball milled for 6 h and 10 h in air at 573 ~ 1 073 K were measured by electrochemical impedance spectroscopy, and their conductivity were calculated to be 3.25 × 10-3 ~ 6.98 × 10-2S.cm-1 and 5.46 × 10-3 ~ 7.20 × 10-2S.cm-1. The relationship between the electrical conductivity and the temperature of the two samples accorded with Arrhenius equation in the range of test temperature, The conductance activation energies are 0.39 eV and 0.34 eV, respectively. Increasing the density of the sintered samples is a function of reducing the conductance And improve the conductivity of the effective way.BaCe0.90Sm0.10O3-α, BaCe0.90Y0.10O3-α and BaCe0.85Y0.15O3-α conductance activation energy in turn, in line with the theoretical prediction.