Abstract

Improving the activity and stability of Fe/N/C catalyst in oxygen reduction reaction (ORR) is a huge challenge in the commercial application of polymer electrolyte membrane fuel cells (PEMFCs). In the past decade, there have been significant break-throughs in the performance of transition metal catalysts, but little progress has been made in their stability. Herein, a zinc-based zeolite imidazole framework (ZIF-8) and tungsten carbide engaged strategy was reported to prepare Fe/N/C catalyst. Particularly, physical vapor deposition (PVD) was used to trap tungsten carbide nanoparticles with particle size of less than 3 nm limited into the FeNC catalytic micropores to synthesis composite catalyst (WC@FeNC). Compared with original Fe/N/C cata-lysts, confined WC nanoparticles in Fe/N/C porous has improved the ORR activity (2.7 mA mg⁻¹ vs. 2.2 mA mg⁻¹ at 0.85 V vs. RHE) as well as stability (decay 18.7 mV vs. 21.6 mV after 10 h charged) in 0.1 M H₂SO₄. This work puts forward some unique insights for improving the stability of transition metal oxygen reduction catalysts.