Low power, low temperature and atmospheric pressure plasma-induced polymerization: facile synthesis and crystal regulation of covalent organic frameworks.

Abstract

Low temperature and atmospheric pressure plasma-induced polymerization was demonstrated as a fast and facile strategy for tailoring of packing phase of COF-1 as well as preparing diverse covalent organic frameworks (COFs) including both two-dimensional (2D) COFs and three-dimensional (3D) COFs. By regulating the solvents, the fast construction of well-ordered AB staggered COF-1 and AA eclipsed COF-1 was facilely realized in minutes. The plasma approach presented here led to the rapid preparation of eight classical 2D COFs, including boronate ester-linkage (COF-5, COF-8 and COF-10), azine-linkage (NUS-2), β-ketoenamine-linkage (TpPa, TPBD), imine-linkage (ILCOF-1, Py-COF), and 3D-COF-102 (boroxine linkage) in less than 1 hour. Different from conventional methods, the proposed methodology required much less time, lower power, no extra heating, inert-gas protection and pressure. The fast nucleation and growth of COFs with good crystallinity, morphology and thermal stability can be achieved under mild conditions.