Fe-N-C氧还原电催化剂的失活机制及延寿策略
Degradation Mechanisms and Durability Improvement Strategies of Fe-N-C Catalysts for Oxygen Reduction Reaction
李隆浩 1周伟 1谢亮 1杨潮伟 1孟晓晓 2高继慧1
作者信息
- 1. 哈尔滨工业大学能源科学与工程学院 哈尔滨 150001
- 2. 哈尔滨工业大学城市水资源与水环境国家重点实验室 哈尔滨 150090;哈尔滨工业大学能源科学与工程学院 哈尔滨 150001
- 折叠
摘要
在质子交换膜燃料电池(PEMFC)中,Fe-N-C催化剂是最有希望替代Pt的非贵金属氧还原(ORR)催化剂.然而目前高活性Fe-N-C催化剂的实际应用仍然受限于其稳定性不足.本文系统总结了 Fe-N-C催化剂常见的合成方法(空间限制法和模板法等),概括了用于评估催化剂稳定性的半电池与单电池测试方法,分析了两种测试结果存在差异的原因,阐述了 Fe-N-C催化剂的4种失活机理,从构筑稳定的碳载体、构筑稳定的活性位点和避免发生Fenton反应三个角度总结了提升稳定性的方法.最后展望了 Fe-N-C催化剂未来的发展方向.
Abstract
Among the many non-precious metal catalysts that have been reported so far,M-N-C catalysts based on transition metal-nitrogen-carbon structure are considered as the most promising candidates to replace Pt-based catalysts for oxygen reduction reaction.Compared with other M-N-C catalysts,Fe-N-C catalysts exhibit the highest ORR activity in acidic environments due to the suitable adsorption energy of oxygen-containing intermediates and thermodynamically favorable 4e pathway.However,the practical application of this catalyst is still limited by the challenge of insufficient stability under the high voltage and strong acidic conditions of PEMFC.Thus,the preparation of stable and efficient Fe-N-C catalysts still faces many challenges.In this review,we systematically summarize the common synthesis methods of Fe-N-C catalysts,including spatial confinement method and template-assisted strategy,outline the half-cell and single-cell test methods used to evaluate the catalyst stability,and analyze the reasons for the discrepancies between the two test results.In order to design highly stable catalysts,a clear knowledge and understanding of the degradation mechanism is required,so we describe four possible degradation mechanisms for Fe-N-C catalysts:demetallization,carbon oxidation,protonation,and microporous water flooding,subsequently we propose some specific strategies to enhance the stability of Fe-N-C catalysts.Finally,the future development direction of Fe-N-C catalysts is discussed in this review.It is hoped that the comprehensive and in-depth study of Fe-N-C catalysts will guide the design and development of highly stable Fe-N-C catalysts for the application of PEMFC.
关键词
质子交换膜燃料电池/氧还原/Fe-N-C催化剂/稳定性/失活机制/延寿策略Key words
proton exchange membrane fuel cell/oxygen reduction reaction/Fe-N-C electrocatalysts/stability/degradation mechanisms/durability improvement strategies引用本文复制引用
基金项目
哈尔滨工业大学城市水资源与水环境国家重点实验室开放基金(HC202331)
出版年
2024
NETL
NSTL
万方数据