Chinese Journal of Catalysis ›› 2019, Vol. 40 ›› Issue (4): 504-514.DOI: 10.1016/S1872-2067(19)63304-8

• Article • Previous Articles     Next Articles

Carbon-supported ultrafine Pt nanoparticles modified with trace amounts of cobalt as enhanced oxygen reduction reaction catalysts for proton exchange membrane fuel cells

Xuejun Tanga,b, Dahui Fanga,b, Lijuan Qua,b, Dongyan Xuc, Xiaoping Qina, Bowen Qina,b, Wei Songa, Zhigang Shaoa, Baolian Yia   

  1. a Fuel Cell System and Engineering Laboratory, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, Liaoning, China;
    b University of Chinese Academy of Sciences, Beijing 100049, China;
    c State Key Laboratory Base of Eco-chemical Engineering, College of Chemical Engineering, Qingdao University of Science and Technology, Qingdao 266042, Shandong, China
  • Received:2018-12-01 Revised:2019-01-11 Online:2019-04-18 Published:2019-03-14
  • Supported by:

    This work was supported by the National Major Research Project (2016YFB0101208), the National Natural Science Foundation of China (21576257), the Natural Science Foundation-Liaoning United Fund (U1508202), and the Strategic Priority Research Program of the Chinese Academy of Sciences (XDB06050303).

Abstract:

To accelerate the kinetics of the oxygen reduction reaction (ORR) in proton exchange membrane fuel cells, ultrafine Pt nanoparticles modified with trace amounts of cobalt were fabricated and decorated on carbon black through a strategy involving modified glycol reduction and chemical etching. The obtained Pt36Co/C catalyst exhibits a much larger electrochemical surface area (ECSA) and an improved ORR electrocatalytic activity compared to commercial Pt/C. Moreover, an electrode prepared with Pt36Co/C was further evaluated under H2-air single cell test conditions, and exhibited a maximum specific power density of 10.27 W mgPt-1, which is 1.61 times higher than that of a conventional Pt/C electrode and also competitive with most state-of-the-art Pt-based architectures. In addition, the changes in ECSA, power density, and reacting resistance during the accelerated degradation process further demonstrate the enhanced durability of the Pt36Co/C electrode. The superior performance observed in this work can be attributed to the synergy between the ultrasmall size and homogeneous distribution of catalyst nanoparticles, bimetallic ligand and electronic effects, and the dissolution of unstable Co with the rearrangement of surface structure brought about by acid etching. Furthermore, the accessible raw materials and simplified operating procedures involved in the fabrication process would result in great cost-effectiveness for practical applications of PEMFCs.

Key words: Proton exchange membrane fuel cells, Oxygen reduction reaction, Ultrafine Pt nanoparticles, Trace amounts of cobalt, Modified glycol method, Chemical etching strategy