报告题目：Role of polarization in the segregation, interface and interphase activity of cathodes of solid oxide fuel cells – A case study of La_0.6Sr_0.4Co_0.2Fe_0.8O_3-d

报告人：蒋三平教授

报告时间：2018年12月14日9:30-11:30

报告地点：华工大学城校区B4-215会议室

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报告人简介：

 蒋三平教授1982年毕业于华南理工大学材料科学与工程专业，于1987年获伦敦城市大学电化学专业博士学位。1988年在英国艾塞克斯大学做博士后研究。1991年为澳大利亚英联邦科技工业研究中心高级研究员，1992年参与澳大利亚燃料电池公司的组建与开发工作。2001年为南洋理工大学机械与航空学院副教授，燃料电池研究中心副主任。2010年为澳大利亚科廷大学化学工程系终身教授，科廷大学燃料与能源技术研究院副院长。在2016年11月被科廷大学授予约翰∙科廷杰出教授和终身成就奖以奖励蒋三平教授在能源与环境研究所做出的杰出贡献。2017年5月被选为澳大利亚西澳华人科学家协会主席，2017年9月被选为中国海外交流协会第六届理事会理事。

    蒋三平教授长期从事电化学能源转换与储存技术方面的研究，特别是在燃料电池领域做了大量的原创性的研究，在世界电化学能源领域具有非常大的学术影响力，是2016年全球高校能源科学与工程学科最具影响力的高被引的学者，2018年度科睿唯安（Clarivate Analytics）跨学科领域（cross-field category）高被引科学家。已在高水平学术期刊上发表了近400篇文章，文章总被引用率18,000次，h-因子69。另有多部知名出版社(Springer-Verlag, CRC Press) 特邀专著与编写章节。蒋三平教授担任 ASME Journal of Electrochemical Energy Conversion and Storage, Journal of Electrochemistry and NPG Scientific Report杂志的编委。并在国际会议多次做邀请报告。他的主要研究方向为固体氧 化物燃料电池电极材料及机理、固体氧化物高温电解材料及机理、质子交换膜燃料电池电催化及反应机理、纳米结构电极、电极/电解质界面现象、高温聚物质子交换膜燃料电池、直接甲醇燃料电池、超极电容等。

报告摘要：

It is generally believed that polarization plays a critical role in the surface segregation, electrode/electrolyte interfaces and interphase reactivity of electrodes of solid oxide fuel cells (SOFCs). This is particularly true for the cobaltite based perovskite electrodes due to their high mixed ionic and electronic conductivity and high activity as oxygen electrodes for O₂ reduction reaction of SOFCs. However, the studies of such fundamental issues are largely limited by the high activity of cobaltite-based perovskites with yttria-stabilized zirconia (YSZ) based electrolyte during the high temperature electrode/cell sintering stages. Most recently, we discovered that electrode/electrolyte interfaces of SOFCs can be formed under the influence of cathodic polarization and the electrode can be directly assembled to YSZ electrolyte without the conventional high temperature sintering. The direct assembly process opens new opportunities for the direct study of the surface segregation, interface formation, interphase reaction and activity of the cathode under the influence of electrochemical as well as chemical driving force. In this presentation, La_0.6Sr_0.4Co_0.2Fe_0.8O_3-δ (LSCF) is selected as a model electrode and studied in details by FIB-STEM and high resolution TEM analysis. The results show the fundamental and intrinsic relationship between the polarization, surface segregation, interface formation and electrode activity, and the feasibility of the in situ formation of the stable electrode/electrolyte interface by manipulation of the phase distribution. Finally, new development in the high temperature polymer electrolyte membrane fuel cells based on the in situ formed phosphosilicate nanocluster proton carriers will also be briefly discussed.