摘要 人类的生存受环境污染和能源危机问题的严重威胁, 所以研发出经济环保型的新能源是人类必须要完成的使命。 固体氧化物燃料电池比较环保, 性能也优越,所以受到该领域的青睐,各个国家正在尽力开发该种电池。但是,传统的固体氧化物燃料电池的工作温度太高,所以它要求电池的材料必须要耐高温,其他配置也要高质量,这样就会升高电池的成本,所以是否能开发出中低温型固体氧化物燃料电池决定了燃料电池的发展前景。后来研究发现,固体氧化物质子导体燃料电池的活化能比较低,能源利用率也很高,所以该种电池成为了科学家们的研究方向。 经过大量研发试验发现中低温时,掺杂的铈酸钡有较高的质子电导率,所以该种质子型陶瓷燃料电池成为人们的首要选择。但是,掺杂铈酸钡的质子导体化学稳定性比较低,而且在二氧化碳,水的环境中化学性比较活跃。当前世界为了提高质子导体燃料电池的稳定性,采取了 Zr4+代替 Ce4+的方法[1]。但是该方法只能有限提高质子导体的化学稳定性,并不能在二氧化碳浓度高的环境中稳定地工作。如果掺入大量的锆来大程度地提高电池的化学稳定性,那么会引起电池材料晶体中的晶粒尺寸变小,而晶界的电阻会随之变大,这样会减小电池的离子电导率,从而使电池的烧结活性大幅下降。 根据掺杂铈酸钡固体氧化物质子导体燃料电池的缺点, 本论文试图研究出新型的阴极材料来弥补以上缺点。 第一章, 介绍了固体氧化物燃料电池的工作原理,发展状况,阴极材料,以及升级版的质子导体固体氧化物燃料电池的工作原理及阴极材料的要求。对本论文主要研究目的进行了说明。 第二章, 为了实现该论文制备出新型阴极材料的目的,进行了严密的合成,所研制的阴极材料为 BaCo0.4Fe0.4Zr0.1Y0.1O3-δ,是与 BCZY 电解质相匹配的一种新型阴极材料,锆可以提高电解质在 CO2 和 H2O 的气氛下的化学稳定性,而铁可以提高导体的电子导电率,降低热膨胀系数。通过固相反应法合成该阴极材料, 通过烧结制成陶瓷导体, 进行 XRD测试,SEM 测试,热膨胀系数测试,直流电阻测试,热差分析测试。 第三章, 通过XRD、SEM 对 BaCo0.4Fe0.4Zr0.1Y0.1O3-δ样品的结构和形貌进行了 详细的表征。由测得数据可分析出,固体反应法可以制成BaCo0.4Fe0.4Zr0.1Y0.1O3-δ钙钛矿相阴极材料。 热膨胀系数测试结果显示该阴极材料的热膨胀系数较低,由直流电阻测试结果分析可知,BaCo0.4Fe0.4Zr0.1Y0.1O3-δ阴极材料电导率较高,化学性较稳定。实验测试结果表明, BaCo0.4Fe0.4Zr0.1Y0.1O3-δ是具有潜力的一种新型阴极材料。 58977
毕业论文键词:阴极 固体氧化物燃料电池 质子导体
Abstract A serious threat to the survival of mankind by environmental pollution and energy crisis, we developed a new environmentally friendly energy economy is a human need to complete the mission. The solid oxide fuel cell more environmentally friendly performance is superior, so favored in this field, each country is trying to develop this type of battery. However, the conventional solid oxide fuel cell operating temperature is too high, it requires a battery of high-temperature materials must be other configurations also high quality, which would increase the cost of the battery, whether it can develop in low temperature the solid oxide fuel cell determines the prospects for the development of fuel cells. Later research found that proton conductor solid oxide fuel cell is relatively low activation energy, energy efficiency is also high, so this type of battery has become the research scientists. After a large number of R & D trial found that low temperature, cerium doped barium has high proton conductivity, so the protonic ceramic fuel cells become the first choice of people. However, cerium-doped barium proton conductor is relatively low chemical stability, but also in carbon dioxide, water, chemicals in the environment relatively active. The current world order to improve the stability of the proton conductor of the fuel cell, instead of taking the Zr Ce approach. However, this method only a limited increase the proton conductor chemical stability, and can not operate stably at high carbon dioxide concentrations in the environment. If the incorporation of a large amount of zirconium to a large extent improve the chemical stability of the battery, the battery can cause material crystal grain size becomes small, and the resistance of the grain boundary will become larger, it will reduce battery ion conductance rate, thereby sintering activity of the battery will be worse. According disadvantage cerium-doped barium proton conductor solid oxide fuel cell, this paper attempts to developed a new cathode material to make up for these shortcomings. BaCo0.4Fe0.4Zr0.1Y0.1O3-阴极材料的合成与电学性能:http://www.751com.cn/wuli/lunwen_64002.html