The rapid development in synthesis methodology and applications for covalent organic frameworks (COFs) has been witnessed in recent years. However, the synthesis of highly stable functional COFs still remains a great challenge. Herein twodimensional polyimide-linked phthalocyanine COFs (denoted as CoPc-PI-COF-1 and CoPc-PI-COF-2) have been devised and prepared through the solvothermal reaction of the tetraanhydrides of 2, 3,9,10,16,17,23, with 1,4phenylenediamine and 4,4′-biphenyldiamine, respectively. The resultant CoPc-PI-COFs with a four-connected sql net exhibit AA stacking configurations according to powder X-ray diffraction studies, showing permanent porosity, thermal stability above 300 °C, and excellent resistance to a 12 M HCl aqueous solution for 20 days. Current−voltage curves reveal the conductivity of CoPc-PI-COF-1 and CoPc-PI-COF-2 with the value of 3.7 × 10 −3 and 1.6 × 10 −3 S m −1 , respectively. Due to the same Co(II) electroactive sites together with similar permanent porosity and CO 2 adsorption capacity for CoPc-PI-COFs, the cathodes made up of COFs and carbon black display a similar CO 2 -to-CO Faradaic efficiency of 87−97% at applied potentials between −0.60 and −0.90 V (vs RHE) in 0.5 M KHCO 3 solution. However, in comparison with the CoPc-PI-COF-2&carbon black electrode, the CoPc-PI-COF-1 counterpart provides a larger current density (j CO ) of −21.2 mA cm −2 at −0.90 V associated with its higher conductivity. This cathode also has a high turnover number and turnover frequency, amounting to 277 000 and 2.2 s −1 at −0.70 V during 40 h of measurement. The present result clearly discloses the great potential of 2D porous crystalline solids in electrocatalysis.

Synthesis of functional 3D COFs with irreversible bond is challenging. Herein, 3D imide‐bonded COFs were constructed via the imidization reaction between phthalocyanine‐based tetraanhydride and 1,3,5,7‐tetra(4‐aminophenyl)adamantine. These two 3D COFs are made up of interpenetrated pts networks according to powder X‐ray diffraction and gas adsorption analyses. CoPc‐PI‐COF‐3 doped with carbon black has been employed to fabricate the electrocatalytic cathode towards CO2 reduction reaction within KHCO3 aqueous solution, displaying the Faradaic efficiency of 88–96 % for the CO2‐to‐CO conversion at the voltage range of ca. −0.60 to −1.00 V (vs. RHE). In particular, the 3D porous structure of CoPc‐PI‐COF‐3 enables the active electrocatalytic centers occupying 32.7 % of total cobalt‐phthalocyanine subunits, thus giving a large current density (jCO) of −31.7 mA cm−2 at −0.90 V. These two parameters are significantly improved than the excellent 2D COF analogue (CoPc‐PI‐COF‐1, 5.1 % and −21.2 mA cm−2).

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An outstanding pH-universal bifunctional electrocatalyst is developed using a novel TMAAE strategy with departure of Br-species attached to the Co–N4 macrocycle.

Synthesis of functional 3D COFs with irreversible bond is challenging.H erein, 3D imide-bonded COFs were constructed via the imidization reaction between phthalocyanine-based tetraanhydride and 1,3,5,7-tetra(4-aminophenyl)adamantine.T hese two 3D COFs are made up of interpenetrated pts networks according to powder X-raydiffraction and gas adsorption analyses.C oPc-PI-COF-3 doped with carbon black has been employed to fabricate the electrocatalytic cathode towards CO 2 reduction reaction within KHCO 3 aqueous solution, displaying the Faradaic efficiency of 88-96 %for the CO 2 -to-CO conversion at the voltage range of ca. À0.60 to À1.00 V( vs.R HE). In particular,t he 3D porous structure of CoPc-PI-COF-3 enables the active electrocatalytic centers occupying 32.7 %o ft otal cobalt-phthalocyanine subunits,t hus giving al arge current density (j CO )o f À31.7 mA cm À2 at À0.90 V. These two parameters are significantly improved than the excellent 2D COF analogue (CoPc-PI-COF-1, 5.1 %and À21.2 mA cm À2 ).