Ordered covalent organic frameworks, COFs and PAFs. From preparation to application

Abstract

In the last years, covalent organic frameworks, COFs, and their derived sub-groups based on auto-assembly of exclusively aromatic units, PAFs, are emerging into the advanced materials field due to their high free porous volume, structural regularity, robustness, hydrothermal stability, and functional variety. Their high gas uptake capacities, presence of stabilized active functions in the framework and charged low-density structures combined with their organization through π-conjugated system arrays open the possibilities of COFs and PAFs to be used as effective materials for adsorption, selective separation and catalysis, and in nanotechnological applications. This review will be focused on self-assembly synthesis mechanisms, physico-chemical characteristics, and applications of this class of promising covalent porous organic structures, outlooking their possible future approaches and perspectives.

Divergent Synthesis of Chiral Covalent Organic Frameworks

“…[19] Fore xample,t he group of MacMillan used the divergent strategy to synthesize six indole alkaloids (categorized into three families) from the same tetracyclic intermediate. [5] In light of the concept of divergent synthesis,w e produced eight CCOFs (categorized into four different types) by at hree-step transformation of ak ey platform molecule, DBCBI. [5] In light of the concept of divergent synthesis,w e produced eight CCOFs (categorized into four different types) by at hree-step transformation of ak ey platform molecule, DBCBI.…”

“…Theresearch area of COFs [5] has gained rapid progress in the past decade.T he features of ac rystalline COF are its framework topology,t he mortise-and-tenon joint, and the functional moiety.M any novel COFs have been ingeniously constructed with the diversity in either the structures or at the covalent joints. [5,6] In this context, further construction of COFs with embedded functional moieties [7] still remains challenging:t arget-oriented synthesis has to meet all the requirements of crystallinity,p orosity,a nd functionality.F or example,a lthough promising in asymmetric catalysis and enantioselective recognition/separation, only ah andful of chiral COFs (CCOFs) have been successfully synthesized.…”

Aptamer‐Functionalized Magnetic Conjugated Organic Framework for Selective Extraction of Traces of Hydroxylated Polychlorinated Biphenyls in Human Serum

“…[1][2][3] The unique characteristics of regular pores, predictable and stable structures, large surface areas, and abundant functional groups endow COFs with excellent performance for extensive applications in gas adsorption, heterogeneous catalysis, optical sensing and components,a nd separation. [1][2][3] The unique characteristics of regular pores, predictable and stable structures, large surface areas, and abundant functional groups endow COFs with excellent performance for extensive applications in gas adsorption, heterogeneous catalysis, optical sensing and components,a nd separation.…”

PAF‐11/poly (dimethylsiloxane) mixed matrix pervaporation membranes for dealcoholization of aqueous solutions

“…High compatibility between fillers and PDMS matrix is crucial for fabrication of MMMs with excellent pervaporation performance. Porous aromatic frameworks (PAFs), containing only carbon and hydrogen atoms within their frameworks, are a new class of porous materials, and offer unique chemical versatility combined with designable framework topologies, large surface areas, low density, strong hydrophobicity, and chemical stability . Nevertheless, to our best knowledge, the incorporation of PAFs in pervaporation membranes has not been reported.…”