Thermo-stability and active site structure of Fe/N/C electrocatalyst for oxygen reduction reaction

Authors

Chi CHEN, State Key Laboratory of Chemical Engineering, East China University of Science and Technology, Shanghai 200237, China;State Key Laboratory of Physical Chemistry of Solid Surfaces, Department of Chemistry,College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, Fujian, China;
Yu-jiao LAI, State Key Laboratory of Physical Chemistry of Solid Surfaces, Department of Chemistry,College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, Fujian, China;
Zhi-you ZHOU, State Key Laboratory of Physical Chemistry of Solid Surfaces, Department of Chemistry,College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, Fujian, China;
Xin-sheng ZHANG, State Key Laboratory of Chemical Engineering, East China University of Science and Technology, Shanghai 200237, China;Follow
Shi-gang SUN, State Key Laboratory of Chemical Engineering, East China University of Science and Technology, Shanghai 200237, China;State Key Laboratory of Physical Chemistry of Solid Surfaces, Department of Chemistry,College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, Fujian, China;Follow

Corresponding Author

Xin-sheng ZHANG(xszhang@ecust.edu.cn);
Shi-gang SUN(sgsun@xmu.edu.cn)

Abstract

The development of Fe/N/C electrocatalyst for oxygen reduction reaction (ORR) is vital for the large-scale applications of proton exchange membrane fuel cells. Understanding the active site structure will contribute to the rational design of highly active catalysts. In this study, the as-prepared Fe/N/C catalyst based on poly-m-phenylenediamine (PmPDA-FeN_x/C) catalyst with the high ORR activity was subjected to the high-temperature heat treatment again at 1000 ~1500 ^oC. The degradation of in the ORR activity of PmPDA-FeN_x/C by with various heat treatments was correlated to the change of elemental compositions, chemical states and textural properties. As the temperature elevated, the Fe atoms aggregated to form nanoparticles, while the gaseous N-containing species volatilized and the amount of N contents decreased, resulting in the destruction of active sites. The XPS analysis revealed that the content of N species with low binding energy show good positive correlation with the ORR kinetic current of catalyst, demonstrating that the pyridinic N and Fe-N species are probably main components of active sites and contribute to the high ORR activity. This study provides a new strategy to investigate the nature of active centre.

Graphical Abstract

Keywords

Fe/N/C electrocatalyst, oxygen reduction reaction, active sites, pyridinic N, Fe-N species

DOI Link

https://doi.org/10.13208/j.electrochem.170324

Publication Date

2017-08-25

Online Available Date

2017-04-10

Revised Date

2017-04-10

Received Date

2017-03-24

Recommended Citation

Chi CHEN, Yu-jiao LAI, Zhi-you ZHOU, Xin-sheng ZHANG, Shi-gang SUN. Thermo-stability and active site structure of Fe/N/C electrocatalyst for oxygen reduction reaction[J]. Journal of Electrochemistry, 2017 , 23(4): 400-408.
DOI: 10.13208/j.electrochem.170324
Available at: https://jelectrochem.xmu.edu.cn/journal/vol23/iss4/5