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A [2 + 2] Schiff base type condensation between 5,10,15,20-tetrakis(4-aminophenyl)porphyrin (TAP) and 1,3,6,8-tetrakis (4-formylphenyl) pyrene (TFFPy) under solvothermal condition yields a crystalline, quasi-two-dimensional covalent organic framework (SB-PORPy-COF). The porphyrin and pyrene units are alternatively occupied in the vertex of 3D triclinic crystal having permanent microporosity with moderately high surface area (∼869 m g) and promising chemical stability. The AA stacking of the monolayers give a pyrene bridged conducting channel. SB-PORPy-COF has been exploited for metal free hydrogen production to understand the electrochemical behavior using the imine based docking site in acidic media. SB-PORPy-COF has shown the onset potential of 50 mV and the Tafel slope of 116 mV dec. We expect that the addendum of the imine based COF would not only enrich the structural variety but also help to understand the electrochemical behavior of these class of materials.

Covalent organic frameworks (COFs) have attracted surging interest lately due to their wide potential in several frontline application areas like gas storage, sensing, photovoltaics, fuel cells, active catalyst supports, and so on. However, only very few reports are available for the metal-free electrocatalysis over COFs. Herein, we developed a new thiadiazole-based COF, C4-SHz COF, through the reaction between 1,3,5-tris(4-formylphenyl)benzene and 2,5-dihydrazinyl-1,3,4-thiadiazole that possesses a very high specific surface area of 1224 m 2 g −1 , unique molecular architecture, high porosity, and abundant active sites. The as-synthesized C4-SHz COF displayed superior electrocatalytic oxygen evolution reaction (OER) activity and excellent long-term durability. The electrocatalytic performance of the C4-SHz COF achieved a current density of 10 mA/cm 2 at an overpotential of 320 mV. The higher activity of the C4-SHz COF could be attributed to the high Brunauer−Emmett−Teller surface area, porosity, and network structure of the π-conjugated organic building blocks, which allowed fast charge and mass transport processes. This work validates the promising potential of a metal-free COF electrocatalyst toward the OER and its capability to replace carbon-based electrocatalysts.