Li Wei, Wang Dongdong, Zhang Yiqiong, Tao Li, Wang Tehua, Zou Yuqin, Wang Yanyong, Chen Ru, Wang Shuangyin
State Key Laboratory of Chem/Bio-Sensing and Chemometrics, Provincial Hunan Key Laboratory for Graphene Materials and Devices, College of Chemistry and Chemical Engineering, The National Supercomputing Center in Changsha, Hunan University, Changsha, 410082, P. R. China.
College of Materials Science and Engineering, Changsha University of Science and Technology, Changsha, 410082, P. R. China.
Adv Mater. 2020 May;32(19):e1907879. doi: 10.1002/adma.201907879. Epub 2020 Mar 16.
The commercialization of fuel cells, such as proton exchange membrane fuel cells and direct methanol/formic acid fuel cells, is hampered by their poor stability, high cost, fuel crossover, and the sluggish kinetics of platinum (Pt) and Pt-based electrocatalysts for both the cathodic oxygen reduction reaction (ORR) and the anodic hydrogen oxidation reaction (HOR) or small molecule oxidation reaction (SMOR). Thus far, the exploitation of active and stable electrocatalysts has been the most promising strategy to improve the performance of fuel cells. Accordingly, increasing attention is being devoted to modulating the surface/interface electronic structure of electrocatalysts and optimizing the adsorption energy of intermediate species by defect engineering to enhance their catalytic performance. Defect engineering is introduced in terms of defect definition, classification, characterization, construction, and understanding. Subsequently, the latest advances in defective electrocatalysts for ORR and HOR/SMOR in fuel cells are scientifically and systematically summarized. Furthermore, the structure-activity relationships between defect engineering and electrocatalytic ability are further illustrated by coupling experimental results and theoretical calculations. With a deeper understanding of these complex relationships, the integration of defective electrocatalysts into single fuel-cell systems is also discussed. Finally, the potential challenges and prospects of defective electrocatalysts are further proposed, covering controllable preparation, in situ characterization, and commercial applications.
诸如质子交换膜燃料电池和直接甲醇/甲酸燃料电池等燃料电池的商业化受到其稳定性差、成本高、燃料渗透以及用于阴极氧还原反应（ORR）和阳极氢氧化反应（HOR）或小分子氧化反应（SMOR）的铂（Pt）及Pt基电催化剂动力学迟缓的阻碍。迄今为止，开发活性和稳定的电催化剂一直是提高燃料电池性能最具前景的策略。因此，人们越来越关注通过缺陷工程来调节电催化剂的表面/界面电子结构，并优化中间物种的吸附能，以增强其催化性能。本文从缺陷的定义、分类、表征、构建和理解等方面介绍了缺陷工程。随后，科学系统地总结了燃料电池中用于ORR和HOR/SMOR的缺陷电催化剂的最新进展。此外，通过结合实验结果和理论计算，进一步阐明了缺陷工程与电催化能力之间的构效关系。随着对这些复杂关系的深入理解，还讨论了将缺陷电催化剂集成到单燃料电池系统中的问题。最后，进一步提出了缺陷电催化剂面临的潜在挑战和前景，涵盖可控制备、原位表征和商业应用。
