SOFC新型对称电极材料的制备与性能研究

发布时间：2018-06-28 03:56

本文选题：固体氧化物燃料 + 电池对称电极　；参考：《长春理工大学》2017年硕士论文

【摘要】：固体氧化物燃料电池(SOFC)作为一种新能源技术,因其具有能量转化效率高、环境友好和燃料适应性强等优点,受到了人们的极大关注。对称电极材料由于采用同一种材料作为SOFC的阴极和阳极材料,不但可以克服硫毒化和碳沉积,也可以在一定程度上减少电池的组成部件,使制备过程变得更加简单,减少了烧结程序,大大降低了电池的制作成本。本文采用溶胶—凝胶法制备了PrBaFe_2O_(5+δ)(PBFO)材料,系统地研究了其作为SOFC对称电极的可行性。研究表明,经过在空气中1100 oC的烧结10 h,可以得到单一的纯相结构;PBFO在850 oC时,空气和氢气中的电导率分别为25S/cm和3.25 S/cm;以H2为燃料,单电池在850 oC时最大输出功率密度为618 mW/cm2,CH4为燃料,单电池在900 oC时最大输出功率密度为220 mW/cm2。良好的电学性能和电化学性能,表明该PBFO有望成为一种新型的SOFC对称电极材料。为进一步提高PBFO对称电极材料在CH4燃料中的电池性能,我们采用化学浸渍的方法,分别制备了Sm0.2Ce0.8O1.9(SDC)浸渍和Co-Fe浸渍的PBFO复合材料。结果表明,SDC的引入增强了材料的离子导电性,从而造成了三相界面的增加,降低了界面电化学阻抗值,提高了电池的输出性能,其中浸渍3次的样品表现出了最佳性能,850oC时H2为燃料,电池最大输出功率为1170 mW/cm2,900 oC时CH4为燃料,电池最大输出功率为380 mW/cm2,分别比浸渍前提高了89%和73%;Co-Fe复合颗粒的引入增强了阳极部分的电子导电能力,降低了界面阻抗值,同样提高了电池的输出性能,其中浸渍4次的样品性能最佳,850 oC时H2为燃料,电池最大输出功率为1496 mW/cm2,900 oC时CH4为燃料,电池最大输出功率为379 mW/cm2,分别比浸渍前提高了142%和73%。综上所述,PBFO及浸渍后的复合材料不仅在H2中表现出了良好的性能,而且在CH4中有很好的电池输出性能,表明该材料可作为一种新型的SOFC对称电极材料使用。
[Abstract]:As a new energy technology, solid oxide fuel cell (SOFC) has attracted much attention because of its high energy conversion efficiency, environmental friendliness and fuel adaptability. Because the symmetric electrode material is used as the cathode and anode material of SOFC, it can not only overcome the sulfur poisoning and carbon deposition, but also reduce the components of the battery to a certain extent, and make the preparation process easier. The sintering process is reduced and the production cost of the battery is greatly reduced. In this paper, PrBaFe2O5 未 (PBFO) materials were prepared by sol-gel method. The feasibility of using PBFO as SOFC symmetric electrode was systematically studied. The results show that after sintering at 1100 OC in air for 10 h, the conductivity of pure phase structure can be obtained at 850oC, the conductivities in air and hydrogen are 25s / cm and 3.25s / cm, respectively, and the hydrogen is used as fuel. The maximum output power density of single cell is 618 MW / cm ~ (2) Ch _ 4 at 850 OC and 220 MW / cm ~ (2) at 900 OC. The good electrical and electrochemical properties indicate that PBFO is expected to be a new type of SOFC symmetric electrode material. In order to further improve the performance of PBFO symmetric electrode materials in CH4 fuel, Sm0.2Ce0.8O1.9 (SDC) impregnated and Co-Fe impregnated PBFO composites were prepared by chemical impregnation. The results show that the introduction of SDC enhances the ionic conductivity of the material, resulting in the increase of the three-phase interface, decreases the electrochemical impedance of the interface, and improves the output performance of the battery. The sample impregnated for 3 times showed the best performance of H _ 2 at 850oC and CH4 at 1170 MW / cm ~ 2900oC as fuel. The maximum output power of the battery is 380 MW / cm ~ 2, which increases the electronic conductivity of the anode part by 89% and 73% Co-Fe composite particles, respectively, and decreases the interface impedance value, and also improves the output performance of the battery. The sample impregnated for 4 times has the best performance of H _ 2 at 850oC, CH4 at 1496 MW / cm _ 2900oC and 379mW / cm ~ 2, which is 14.2% and 73.75% higher than that before impregnation, respectively. In conclusion, PBFO and impregnated composites not only have good properties in H2, but also have good battery output performance in CH4, which indicates that the composite can be used as a new type of SOFC symmetric electrode material.
【学位授予单位】：长春理工大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TM911.4;TB33

【参考文献】