A potential well effect for efficient oxygen reduction and corrosion resistance under the operating temperature conditions of PEMFCs

In recent years, fluorine-doped carbon (F-C) materials have attracted widespread attention in the oxygen reduction reaction (ORR) due to their unique performance. However, the strong electron-withdrawing nature of the F element makes metal particles not suitable for the 4e⁻ ORR in proton exchange membrane fuel cells (PEMFCs). In this work, we introduce Zn element to modulate the strong electron-withdrawing effect of F element. At the same time, utilizing the strong polarity of the C-F bond, we construct an electron confinement structure to introduce the concept of potential well in the ORR system for the first time. We prepare the PtZn i-NPs/F-CNT catalyst with a potential well effect to achieve high ORR catalytic efficiency. The catalyst exhibits good ORR performance and corrosion resistance at 80 °C. Furthermore, the PtZn i-NPs/F-CNT cathode assembly reaches a peak power density of 1.49 W cm⁻² in the H₂/O₂ environment and maintains 92.6% of the peak power density after 30 K cycles of accelerated stress testing (AST), with stable operation for 220 hours at a working voltage of 0.67 V. This study offers novel insights into developing efficient and corrosion-resistant ORR electrocatalysts for PEMFCs, serving as a foundation for future development of ORR electrocatalysts in PEMFCs.