Two-Dimensional Leafy Fe/N-Doped Carbon Nanomaterials Derived from Vitamin C-Modified ZIF-L for Efficient Oxygen Reduction Reaction

Oxygen reduction reaction (ORR) is an important half-reaction in various energy devices such as fuel cells. Here, 2D dendritic Fe/N co-doped carbon-based nanosheet composites (L-Fe-CNT@NCS-900) were obtained by high-temperature calcination using ZIF-L generated in the aqueous phase as a precursor and Vitamin C as a modifier. It is found that the catalysts calcined at 900℃ possessed the large specific surface area and the pore size distribution graphs showed a narrow micropore size distribution centered at about 1.8 nm. Furthermore, the Fe-N-C species was detected, which further improved the ORR performance as an active center. Thus, the L-Fe-CNT@NCS-900 calcined at 900 °C achieved the best ORR performance with a half-wave potential (E_1/2) of 0.85 V, and the hydrogen peroxide yield is only about 4% during the ORR process. Meanwhile, L-Fe-CNT@NCS-900 exhibited outstanding methanol resistance. This work proposes a new strategy for constructing an efficient electrocatalysts for oxygen reduction reaction.