A lignin-derived N-doped carbon-supported iron-based nanocomposite as high-efficiency oxygen reduction reaction...

Fuel cells are a promising renewable energy technology that depend heavily on noble metal Pt-based catalysts, particularly for the oxygen reduction reaction (ORR). The discovery of new, efficient non-precious metal ORR catalysts is critical for the continued development of cost-effective, high-performance fuel cells. The synthesized carbon material showed excellent electrocatalytic activity for the ORR, with half-wave potential (E_1/2) and limiting current density (JL) of 0.88 V and 5.10 mA·cm^-2 in alkaline electrolyte, respectively. The material has a Tafel slope of (65 mV dec^-1), which is close to commercial Pt/C catalysts (60 mV dec^-1). Moreover, the prepared materials exhibited excellent performance when assembled as cathodes for zinc-air batteries. The power density reached 110.02 mW cm^-2 and the theoretical specific capacity was 801.21 mAh g^-1, which was higher than that of the Pt/C catalyst (751.19 mAh g^-1). In this study, with the assistance of Mg₅(CO₃)₄(OH)₂·4H₂O, we introduce an innovative approach to synthesize advanced carbon materials, achieving precise control over the material's structure and properties. This research bridges a crucial gap in material science, with potential applications in renewable energy technologies, particularly in enhancing catalysts for fuel cells.