Zeolitic-imidazolate-framework-derived Fe-NC catalysts towards efficient oxygen reduction reaction

The development of non-precious metal catalysts to replace scarce and expensive Pt-based catalysts is critical for oxygen reduction reactions (ORR), where zeolitic-imidazolate-framework-derived (ZIF-derived) iron-based electrocatalysts hold a promising prospect. Herein, Fe3O4 was used as Fe source, and ZIF-8 was used as C and N source to prepare Fe-NC catalysts. Specifically, the half-wave potential (E1/2) of the Fe-NC reached 0.90 V, which was higher than commercial Pt/C catalysts (0.87 V), and the overpotential of OER reached 327 mV. In addition, the power density tested in Zn-air batteries upped to 129.59 mW cm−2, surpassing that of the Pt/C (108.93 mW cm−2). The superior performance was attributed to the effective introduction of Fe, the large specific surface area (851.6 m2 g−1), relatively regular porous structure and the high degree of graphitization.