Energy Storage Science and Technology ›› 2022, Vol. 11 ›› Issue (4): 1264-1277.doi: 10.19799/j.cnki.2095-4239.2022.0108

• Special issue of International Outstanding Young Scientists for Energy Storage • Previous Articles     Next Articles

Recent progress in confined noble-metal electrocatalysts for oxygen reduction reaction

Yezhou HU1(), Shuang WANG2, Tao SHEN2, Ye ZHU1(), Deli WANG2()   

  1. 1.Department of Applied Physics, The Hong Kong Polytechnic University, Hong Kong 999077, China
    2.Key Laboratory of Material Chemistry for Energy Conversion and Storage, Huazhong University of Science and Technology, Wuhan 430074, Hubei, China
  • Received:2022-03-01 Revised:2022-03-23 Online:2022-04-05 Published:2022-04-11
  • Contact: Ye ZHU,Deli WANG E-mail:huyezhou@163.com;yezhu@polyu.edu.hk;wangdl81125@ hust.edu.cn

Abstract:

Developing highly efficient oxygen reduction reaction (ORR) electrocatalysts is one of the main techniques to achieve the large-scale application of proton exchange membrane fuel cells (PEMFCs). Noble-metal based catalysts, as robust ORR catalysts, are the most likely candidates for practical application. The large-scale use of noble metal may lead to a high cost of the catalysts. On the other hand, the stabilities of noble-metal catalysts still need further improvements. Confining noble-metal catalysts in physical confinement layer can greatly improve catalytic stability without compromising initial activity, thus prolonging the service life of catalysts. The physical confinement layers can not only inhibit the coalescence of catalysts during high-temperature preparation, but also mitigate the aggregation, detachment and dissolution during electrochemical process. In this review, confined noble-metal ORR catalysts are reviewed, including conducting polymer confined noble-metal catalysts, non-metal-oxide confined noble-metal catalysts, metal-oxides confined catalysts and carbon confined catalysts. Besides, the structure-performance relationship between confinement layers' physical properties and electrocatalytic performance is analyzed. Three main strategies to achieve carbon confinement are emphasized, including 'deposition-conversion' strategy, 'insertion-conversion' strategy and 'one-step pyrolysis' strategy. At last, summary and prospect are given, also some existing challenges are stated.

Key words: proton exchange membrane fuel cells, oxygen reduction reaction, confined noble-metal based electrocatalysts, physical confinement layer, electrocatalytic stability

CLC Number: