直接生物质气固体氧化物燃料电池新型钼酸盐钙钛矿阳极材料的研究

One of the significant advantage of solid oxide fuel cell (SOFC) is fuel flexibility because of high operating temperature (500-1000℃). In recent years, traditional hydrogen replacement by more and more accessible fuels is one of the main research directions of SOFC. Biogas is one of the most potential and renewable energy, which is readily available from various sources. Besides, it is demonstrated that SOFCs are highly adaptable to the characteristics of low net caloric value and frequent composition change of biogas. However, traditional Ni based anode is susceptible to degradation via carbon deposition when hydrocarbon is used as fuel. With the aim of utilization of biogas efficiently, in this study, a novel Mo-based perovskites material is developed. Titanium or Manganese is doped in B site of Sr2NiMoO6-δ, in order to increase the stability under reducing atmosphere and the resistance to carbon deposition. Moreover, the composition and microstructure of the material, high temperature transport properties of electron and ion, as well as the electrochemical process of utilization of biogas are also investigated. The cell performance is tested using biogas as fuel with different composition. This design of direct biogas SOFC anode could provide guidance of theoretical and experimental basis.

固体氧化物燃料电池（SOFC）由于在较高的操作温度（500-1000℃）下工作，所以具有燃料适用性强的显著优点。目前，SOFC的一个主要发展方向就是采用易获取的燃料替代传统的氢能。生物质气是颇具潜力的可再生能源之一。SOFC能很好地适应生物质气热值低、组成变化大的特点。但是，SOFC要采用生物质气为燃料发电，必须克服传统的SOFC镍基阳极在以碳氢化合物为燃料时出现的碳沉积问题。本项目以生物质气的高效利用为目标，探索新型钼酸盐钙钛矿型阳极，利用元素Ti或Mn对Sr2NiMoO6-δ材料的B位进行部分取代，在稳定材料结构的基础上兼顾材料高的电化学催化活性和抗积碳性能。系统地研究该类材料的晶体结构、微结构、高温离子电子输运机制、生物质气在阳极的电催化氧化反应机理，并研究生物质气的组成对电池输出性能的影响，为设计直接生物质气SOFC阳极材料提供理论和实验依据。

本项目以生物质气的高效利用为目标，探索新型双钙钛矿型PrBaMn2O6-δ材料，利用元素铁掺杂对PrBaMn2O6-δ材料的B位进行部分取代，在稳定材料结构的基础上兼顾材料高的电化学催化活性和抗积碳性能。系统地研究在掺杂不同比例时PrBaMn2-xFexO6-δ(x=0,0.5,1,1.5)材料的晶体结构、微结构、高温离子电子输运机制。结果表明铁的掺杂提高了材料的电子电导率，使得热膨胀系数稍有增加，而在空气气氛以及氢气气氛下对称电池极化电阻均有不同程度的降低。同时作为阳极和阴极材料时电池性能相比传统钙钛矿材料有明显提升。此外，测试了以氢气，甲烷和直接生物质气为燃料时阳极的电催化氧化反应活性，并研究生物质气的载气和组成对电池输出性能的影响，为设计直接生物质气SOFC阳极材料提供了理论和实验依据。