Hydrogen fuel cells are expected to play dominant role in future clean energy solutions for various applications, particularly for electric vehicles (EVs). However, the use of expensive and rare Pt-based catalysts for oxygen reduction reaction (ORR) at the cathode is one of the main obstacles to the widespread commercialization of hydrogen fuel cells. Therefore, developing highly efficient low-Pt and Pt-free ORR catalysts is one of the key solutions to solve the above-mentioned challenges. Non-precious metal-based Fe/N/C catalysts are considered as one of the most promising Pt-free ORR catalysts. INRS team has made major breakthroughs on Fe/N/C catalyst, with the membrane electrode assembly (MEA) activity and performance approaching that of Pt in hydrogen fuel cells [1, 2]. However, the durability of all the reported non-noble metal catalysts (including Fe/N/C) is still insufficient for practical applications and its performance decay mechanism is still unclear.

We made systematic studies to verify whether iron is at the origin of the first rapid decay (stability problem) of the Fe/N/C catalyst for ORR in PEM fuel cells [3-5]. We further discovered that the pore size near the active FeN₄ sites and the hydrophobicity play essential roles in the catalyst stability of Fe/N/C catalysts [6, 7]. Moreover, we also developed other types of Pt-free catalysts for ORR in fuel cells [8-13]. In addition, thermodynamic stability and DFT evaluations have been employed to study the Fe-based ORR catalysts [4, 14]. On the other hand, a series of low-Pt catalysts, including Fe/N/C and ultra-low loading Pt/C hybrid, Pt nanowires, nanotubes and single atoms for fuel cells, will also be presented [15, 16]. In the end, I will very briefly introduce our other research activities on H₂ generation, lithium metal batteries and Zn-air batteries [17-21].

Reference：

1. Lefevre, E.Proietti, J. P. Dodelet, et al, Science 2009, 324, 71.
2. Proietti, F. Jaouen, J. P. Dodelet, et al, Nature Communications, 2011, 2, 416.
3. Zhang, S. Sun, J. P. Dodelet, et al, Nano Energy, 2016, 29, 111.
4. Zhang, S. Sun, J. P. Dodelet, et al, Energy Environmental Science, 2019, 12, 3015.
5. Dodelet, V. Glibin, G. Zhang, S. Sun, et al, Energy Environmental Science, 2021, 14, 1034.
6. Chenitz, S. Sun, J. Dodelet, et al, Energy Environmental Science, 2018, 11, 365.
7. Yang, Y. Wang, S. Sun, et al, Applied Catalysis B: Environmental. 2020, 264, 118523.
8. Wei, Y. Fu, G. Zhang, S. Sun, et al, Nano Energy. 2019, 55, 234.
9. Komba, S. Sun, et al, Applied Catalysis B: Environmental. 2019, 243, 373.
10. Liu, L. Xu, S. Sun, et al, Applied Catalysis B: Environmental. 2019, 243, 86.
11. Wei, X. Yang, G. Zhang, S. Sun, et al, Applied Catalysis B: Environmental. 2018, 237, 85.
12. Li, Y. Song, G. Zhang, H. Liu, S. Sun, et al, Adv. Funct. Mater. 2017, 27, 1604356.
13. Zhang, A. Tavares, S. Sun, et al, Applied Catalysis B, 2017, 206, 115.
14. Glibin, M. Cherif, S. Sun, et al, J. Electrochem. Soc., 2019, 166, F3277.
15. Yang, G. Zhang, S. Sun, et al, ACS Applied Materials & Interfaces. 2020, 12, 13739.
16. Chang, D. Yang, G. Zhang, S. Sun, et. al, Applied Catalysis B: Environmental, 2017, 211, 2015.
17. Wu, G. Zhang, S. Sun, et al, Adv. Energy Mater. 2018, 1801836.
18. Wu, G. Zhang, S. Sun, et al, Energy Storage Materials, 2020, 24, 272.
19. Wu, G. Zhang, S. Sun, et al, Nano Energy, 2021, 79, 105409.
20. Wu, G. Zhang, S. Sun, et al, ACS Energy Letters, 2021, 6, 1153.
21. Dai, C. Lai, S. Sun, et al, Nature Communications, 2020, 11, 643.