A New Cobalt-Based Metal-Organic Framework for Robust Electrocatalytic Oxygen Reduction at 200 mA cm^-2

Metal-organic frameworks (MOFs) have been widely exploited as promising heterogeneous catalyst, but it is still challenging for them to own the robustness of electrocatalysis at the current density of over 100 mA cm^-2. Herein, one Co-N₄-based MOF is reported, featuring strong chelation interaction of metal/linker and strong interlayer π…π stacking, with to own extraordinary stability for alkaline ORR with almost unity of H₂O₂ selectivity. It can robustly drive the ORR at 200 mA cm^-2 for 130 h, and produce H₂O₂ with mass activity (7540 A·g_catalyst ^-1) and TOF value (40.7 s^-1 per Co-N₄ site), representing the most stable and active MOF-type ORR electrocatalyst. As benefited from the well-defined structure feature of MOFs, the unprecedented ORR performance is unraveled to result from its excellent conductivity and homogeneously dispersed Co-N₄ active sites with high intrinsic activity.