直接碳固体氧化物燃料电池高效稳定镍基阳极的精准构筑及其热质传递机理研究

Performance degradation is one of the challenging scientific problems during the development of direct carbon solid oxide fuel cell (DC-SOFC) because of the sluggish electrochemical oxidation reaction in the anode. In this project, the high-performance Ni-based anode catalysts will be developed to improve the durability. The influence rule of the surface and interface reaction in the anode, including surface composition, morphology, molecular interaction and stress conditions etc., toward the electrochemical performance of DC-SOFC will be investigated by the in situ characterization. Subsequently, the regulatory mechanism of surface and interface properties to the electrochemical reaction and dynamics process of ion transport will be clarified. Combined with the theoretical simulation, the link in catalytic activity, electrochemical activity and resistances of sulfur and carbon deposition will be established to achieve the precise construction for the high-efficiency and steady Ni-based anode of DC-SOFC. Infinite element modeling will be applied to simulate the heat-mass transfer and electric-chemical reaction to build a mathematical model for the DC-SOFC system. As a result, the mechanism of multi-dimensional heat-mass and charge transfer will be revealed, and the results will be compared with those obtained from experiments. Based on above researches, the science linkage between anode catalysts, system structure, operating parameters and electrochemical performance will be established to realize the efficient and stable operation of DC-SOFC. The proposed research will provide theoretical foundation and scientific basis for the development of low-cost, high-performance and long-life DC-SOFC.

直接碳固体氧化物燃料电池（DC-SOFC）阳极侧的电化学氧化反应涉及多组分和多电子转移，动力学路径多，导致电池性能随时间而衰减，制约了其发展。本项目拟设计合成新型镍基阳极催化剂并组装电池，原位研究阳极表界面反应过程中表面成分、形貌、分子相互作用和应力等对电池性能的影响规律，在原子-分子层面阐明表界面性质对电化学反应和离子传输动力学过程的调控机理；结合理论模拟，建立阳极催化活性、电化学活性和抗积碳/硫中毒能力的关联机制，实现DC-SOFC高效稳定镍基阳极的精准构筑；采用有限元方法，研究DC-SOFC传质、传热和电化学反应过程，建立DC-SOFC数学模型，揭示多维度传热、传质和传荷机理；调控新型镍基阳极的催化活性，建立阳极催化剂-电池结构-运行参数-电化学性能之间的科学关联，实现DC-SOFC的高效稳定运行。本项目的实施，将为发展高效长寿命DC-SOFC提供理论基础和科学依据。

针对直接碳固体氧化物燃料电池（DC-SOFC）输出性能低和运行稳定性差这一科学难题，本项目主要开展了DC-SOFC高效稳定镍基阳极的精准构筑及其热质传递机理研究。原位研究了高温下镍基阳极与甲烷的相互作用过程，结合微观形貌表征，揭示了镍基阳极积碳失效机理；设计合成了新型镍基阳极催化剂并组装成电池，深入研究了DC-SOFC阳极表界面反应过程中表面成分、形貌、分子相互作用和应力情况等对电池性能的影响规律，揭示了阳极表界面性质对电化学反应和离子传输动力学过程的调控机理，提高了DC-SOFC电化学性能、烧结性能和系统发电效率；模拟研究了DC-SOFC系统传质、传热和电化学反应过程，揭示了DC-SOFC发电过程中多维度传热、传质和传荷机理，结合实验研究结果，建立了阳极催化剂-电池结构-运行参数-电化学性能之间的科学关联，确定了最佳的电池结构和运行参数；开发了新型逆向Boudouard反应催化剂，研究了催化剂类型和担载量对电池性能和燃料利用率的影响，揭示了不同类型催化剂的催化机理；开发了一系列生物质炭燃料，系统研究了生物质炭微观结构、比表面积、石墨化程度、化学组成及分布等对DC-SOFC电化学性能的影响规律，实现了DC-SOFC的高效长寿命运行；开发了新型高催化活性的钙钛矿阳极材料，系统研究了材料化学组成和微观结构等对电池输出性能、运行稳定性和系统转换效率的影响规律。本项目的实施，为发展低成本、高性能和长寿命DC-SOFC提供了理论基础和技术支撑。