Microtubular Self‐Assembly of Covalent Organic Frameworks. Issue 3 (13th December 2017) - Gole, Bappaditya
Abstract: Despite significant progress in the synthesis of covalent organic frameworks (COFs), reports on the precise construction of template‐free nano‐ and microstructures of such materials have been rare. In the quest for dye‐containing porous materials, a novel conjugated frameworkDPP‐TAPP‐COF with an enhanced absorption capability up to λ =800 nm has been synthesized by utilizing reversible imine condensations between 5, 10, 15, 20‐tetrakis(4‐aminophenyl)porphyrin (TAPP ) and a diketopyrrolopyrrole (DPP ) dialdehyde derivative. Surprisingly, the obtained COF exhibited spontaneous aggregation into hollow microtubular assemblies with outer and inner tube diameters of around 300 and 90 nm, respectively. A detailed mechanistic investigation revealed the time‐dependent transformation of initial sheet‐like agglomerates into the tubular microstructures. Abstract : Rolling up the COFs : Tetraphenylporphyrins and diketopyrrolopyrroles have been incorporated as functional dye components in covalent organic frameworks by means of reversible imine condensations. Upon formation, these crystalline polymers spontaneously self‐assemble to form hollow microtubes.