Sulfur-Doped CuFe–N–C Nanoparticle Catalysts for Anion Exchange Membrane Fuel Cells

The development of cost-effective and durable nonprecious metal catalysts with high oxygen reduction reaction (ORR) activity is essential for advancing anion exchange membrane fuel cells (AEMFCs). However, simultaneously achieving high ORR activity and long-term stability remains a challenge. In this work, a sulfur-doped bimetallic carbon-based catalyst (CuFe–S–N–C) is synthesized through a hydrothermal method followed by high-temperature pyrolysis. As an ORR catalyst, CuFe–S–N–C exhibits a half-wave potential (E1/2) of 0.883 V and a Tafel slope of 65.6 mV dec–1. After 10,000 cycles, the E1/2 decreases by only 7 mV, indicating high electrochemical durability, which could be attributed to the synergistic effects of sulfur doping and Cu/Fe dual-metal sites. When CuFe–S–N–C is used as the cathode catalyst, the AEMFC achieves a peak power of 673.8 mW cm–2 and maintains 96.2% of its initial performance after 15 h of continuous operation.