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 plasmainduced 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), b-ketoenaminelinkage (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.Covalent organic frameworks (COFs) are a novel class of porous materials with predesignable two-dimension (2D) and three-dimension (3D) structures [1] composed of organic subunits linked by covalent bonds. [2] COFs have demonstrated attractive properties including good crystallinity, high surface area, exceptional stability, permanent porosity and low density, which make COFs very promising for diverse applications in gas capture, [3] separation, [4] sensing, [5] catalysis [6] and semiconductors. [7] The last two decades witnessed blooming studies of COFs, [8] in which most COFs are

Modulating the Stacking Model of Covalent Organic Framework Isomers with Different Generation Efficiencies of Reactive Oxygen Species

“…Thereby, layer stacking models could exhibit a profound influence on the electronic and optic properties of COF isomers . There are some strategies that have been explored to control the layer stacking of COFs, such as controlling the concentrations of alkyl groups by a multivariate component (MTV) approach and a liquid dielectric barrier discharge (DBD) plasma-catalyzed strategy . However, it remains challenging to develop a facile synthesis and controllable layer stacking approach for 2D COFs.…”

“…35 There are some strategies that have been explored to control the layer stacking of COFs, such as controlling the concentrations of alkyl groups by a multivariate component (MTV) approach 36 and a liquid dielectric barrier discharge (DBD) plasma-catalyzed strategy. 37 However, it remains challenging to develop a facile synthesis and controllable layer stacking approach for 2D COFs. Thus, it is very meaningful to construct COF isomers and explore the relationship between their structures and properties.…”

Aqueous Synthesis of Covalent Organic Frameworks as Photocatalysts for Hydrogen Peroxide Production

“…7 Different methods have been developed for the production of COFs, such as solvothermal method, 8 microwave thermal method, 9 ionic thermal method, 10 mechanical grinding, 11 light/electrically promoted and plasma induced synthesis. [12][13][14] Unfortunately, the crystallization of COFs with these methods typically relies on trial and error involving harsh conditions such as high temperature, high pressure, flammable and toxic organic solvents, and inert or vacuum atmosphere. 15 Even if a crystallization condition was determined for a specific structure, exhaustive refinements are required upon minor change of monomer structures in the synthesis of COFs, 16 presenting significant obstacles to the rational design of their structures and functionalities as well as large-scale production.…”

Morphological control of covalent organic frameworks in a PEG–H2O system

“…15 Based on these perceptions, to alleviate or circumvent these shortcomings and develop an expeditious synthesis of COFs, a great deal of investigation has been conducted to develop green and high-throughput synthesis strategies with regard to new types of energy sources and green reaction media. With respect to new energy sources, various strategies, such as microwave-assisted solvothermal methods, 16–18 electron beam irradiation, 14 and low-temperature plasma induction, 19 have been developed to accelerate the synthesis of COFs by virtue of their unique radiation heating. Water, as the most abundant and greenest solvent in nature, is the first candidate for green reaction media.…”