Y2O3对Na2O-BaO-CaO-B2O3-SiO2封接玻璃析晶的影响

Effect of Y2O3 on Crystallization Behavior of Na2O-BaO-CaO-B2O3-SiO2 Sealing Glass

中温固体氧化物燃料电池在新能源发展领域中占据重要的地位,而良好的封接玻璃对于其商业化发展影响显著,以Na2O-BaO-CaO-B2O3-SiO2封接玻璃为基础,结合热膨胀曲线、物相分析(XRD)、扫描电镜(SEM)等测试手段,探究Y2O3对其析晶行为的影响。结果表明,Y2O3的引入对于Na2O-BaO-CaO-B2O3-SiO2封接玻璃的热膨胀系数影响较小,均处于11.0-11.6×10^-6℃-1之间,但根据其含量的变化与温度转变点的关系,Y2O3有助于提高玻璃的稳定性;XRD的结果显示,Y2O3的引入有利于析出Ba1.55Ca0.45SiO4晶体,同时抑制Ba0.9Ca0.1SiO3晶体的生成,再结合SEM可知Y2O3的引入有利于细化晶粒,促进单一晶体的析出,且Ba1.55Ca0.45SiO4晶粒形貌呈片状生长,Ba0.9Ca0.1SiO3晶体呈柱状生长。根据Y2O3-Na2O-BaO-CaO-B2O3-SiO2封接玻璃的热稳定性及其与半电池间的断面可知,当封接玻璃中Y2O3含量为1mol%时,其与固体氧化物燃料电池间的结合性良好。

The intermediate temperature solid oxide fuel cell occupies an important position in the development of new energies,whereas the performance of the sealing glass has a significant impact on its commercialization.The effect of Y2O3 on crystallization behavior of Na2O-BaO-CaO-B2O3-SiO2 sealing glass was studied with thermal mechanical analysis,phase analysis(XRD),scanning electron microscopy(SEM)and other testing methods.It is found that the introduction of Y2O3 has only a very slight effect on thermal expansion coefficient of the Na2O-BaO-CaO-B2O3-SiO2 sealing glass,with values in the range of 11.0-11.6×10^-6℃^-1.However,according to the relationship between the content and the temperature transition point,Y2O3 has a positive effect on stability of the glass.XRD results reveal that the introduction of Y2O3 is beneficial to the crystallization of Ba1.55Ca0.45SiO4,while inhibiting the formation of Ba0.9Ca0.1SiO3.SEM results indicate that the introduction of Y2O3 is beneficial to the refinement of the crystalline grains and the precipitation of single crystals.The Ba1.55Ca0.45SiO4 grains have a sheet morphology,while the Ba0.9Ca0.1SiO3 crystals possess a columnar shape.According to the thermal stability and the cross-section between the glass and the half-cell,the optimal content of Y2O3 is 1mol%.