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Constructing heterostructures of covalent organic frameworks (COFs) and metal organic frameworks (MOFs) have gained great attention for various applications due to their well-defined skeletons, ordered porosity and designable functions. Herein, the core-shell structured carbon frameworks, which contain high density active sites of uniform Co nanoparticles and atomic Co-N4, were realized by direct prolysis of TP-BPY-COF@ZIF-67. The thin COF-shell not only prevented the collapse and aggregation of ZIF-67 but also promoted the formation of mesopores for mass transport, and enhanced the graphitization degree for conductivity. The resulant COF@ZIF800 exhibited bifunctional catalytic performance in ORR and HER, in which the excellent ORR performance with half-wave potential of 0.85 V in 0.1 M KOH and the outperformed catalytic behavior for HER with an over-potential of 0.16 V at 10 mA cm-2 in 1 M KOH were achieved. This work sheds light on exploring COFs and MOFs in electrochemical energy storage and conversion systems.

Construction of catalytic covalent organic frameworks (COFs) for oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) is significant but rarely demonstrated. In this work, we have first constructed bifunctional COFs towards ORR and OER by integrating diarylamine derivatives into the Co-porphyrin based frameworks. Both of the new COFs (CoTAPP-PATA-COF and CoTAPP-BDTA-COF) have good ordered structures, high surface areas, and robust chemical stability. The diarylamine units, as a typical electron donor and redox-active cores, promote intramolecular electron transport along the frameworks and improve the electrochemically active surface areas. Thus, the COFs showed higher catalytic activities than that of the COF without redox-active units. CoTAPP-PATA-COF had a halfwave potential of 0.80 V towards ORR, and delieved an overpotential of 420 mV for OER in 0.1 M KOH. The theoretical calculation revealed introducing diarylamine unites improved the oxygen electrocatalysis.