摘要固体氧化物燃料电池（SOFC）因其高效、环保等优点作为绿色能源得到普遍 的研究。其成功应用将有效地节约能源并减少能源利用时对环境造成的污染，因 此对社会的可持续发展具有重大意义。为了实现 SOFC 的商品化，使之更多地应 用到生产生活中，如何降低 SOFC 的工作温度，开发中温（500℃-800℃）固体氧 化物燃料电池（IT-SOFC）已成为研究热点。然而由于温度降低，电极的电化学性 能也会随之降低，因而开发高催化活性的新型阴极材料成为 IT-SOFC 性能提高的 关键。68577

本论文围绕开发 IT-SOFC 阴极材料的目标，重点研究了钛矿型 LaNi0.6Fe0.4O3 作为阴极材料时的电导率、热膨胀性、电化学性能等，制备了适合 IT-SOFC 高催 化活性阴极材料。主要的研究内容如下：

(1)为了降低阴极材料 LaNi0.6Fe0.4O3 的烧结温度，文中采用甘氨酸燃烧合成法 制备了 LaNi0.6Fe0.4O3 超细粉体；进行压条研究其热膨胀性，热膨胀系数为 11～ 11.4×10-6/℃，与 SDC 的热膨胀系数相匹配。

（2）研究了利用离子浸渍法进行阴极微结构表面修饰，优化阴极微结构来提 高阴极性能。对 LaNi0.6Fe0.4O3 浸渍 SDC 纳米颗粒成功的提高了复合阴极的电化学 性能，浸渍比例为 15%时性能最优，800oC 时极化电阻仅为 0.011Ω·cm2，而未浸 渍的阴极极化电阻为 0.28Ω·cm2。浸渍最佳烧结温度为 800℃。

毕业论文关键词 固体氧化物燃料电池（SOFC）,阴极材料,LaNi0.6Fe0.4O3，，催化活性

Title Catalytic Activity Research of Anti Chromium Poisoning LaNi0.6Fe0.4O3    for SOFC Cathode

Abstract

Solid oxide fuel cell (SOFC) as green energy has been widely researched because of its high energy efficiency and clean energy conversion. Its successful application will effectively save energy and reduce energy use on the environment caused by pollution. Therefore, it has great signi- ficance for sustainable development of the society.In order to realize the commercializa tion of SOFC and apply widely to production and life, it has become a hot research topic.To reduce the working temperature of SOFC and develop medium temperature (500℃ -800℃) solid oxide fuel cell.However, the electrochemical activity of the cathode dramati- cally decreases with reducing temperature. Developing new cathode material with high catalytic activity is a key to improve the performance of IT-SOFC.

In this paper, developing novel structure, cation doping and micro- structure optimizating have acted as important parts of developing new cathodes materials, which is qualified as cathodes of IT-SOFC. The details are written as follows:

(1) LaNi0.6Fe0.4O3 power is synthesized by a GNP method. Electrical conductivity and thermal expansion are researched. The electrical con- ductivity is 580 S·cm-1 at 800℃and its thermal expansion coefficients (TEC)

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of LaNi0.6Fe0.4O3  are 11～11.4 ×10 /℃ in 25℃–800℃, exhibiting good physical compatibility with samarium doped cerium (SDC) electrolyte.(2) SDC nanoparticles modified LaNi0.6Fe0.4O3(LNF) cathode were fabricated by an infiltration technique and evaluated for intermediate- temperature solid oxide fuel cells (IT-SOFCs). The electro-catalytic property of the composite cathodes were improved by infiltration technique and the composite cathode with infiltrated ratio of 15% is demonstrated most excellent with a polarization resistance of 0.011Ω·cm2 at 800oC ,

while polarization resistance of LNF without impergiatation was 0.28 Ω·cm2 at the same temperature. And the optimum sintering temperature for impregnated film was 800℃.