Chemically stable polyarylether-based covalent organic frameworks

Abstract

The development of crystalline porous materials (CPMs) with high chemical stability is of paramount importance for their practical uses. Here we report the synthesis of novel polyarylether covalent organic frameworks (PAE-COFs) with high crystallinity, porosity and exceptional chemical stability due to the inert nature of polyarylether building blocks. We demonstrate that these materials can be stable against harsh chemical environments involving boiling water, strong acids/bases, oxidation and reduction conditions, which exceed all known CPMs, including zeolites, metal-organic frameworks (MOFs) and COFs. Furthermore, we explore their advantages as an efficient platform for structural design and functional evolution. The functionalized PAE-COFs combine porosity, high stability, and recyclability, and deliver outstanding performance in the removal of antibiotics from water over a wide pH range.

Covalent Organic Frameworks (COFs) for Cancer Therapeutics

“…As a promising alternative to MOFs, COFs can essentially be considered as nanomedicine candidates for cancer treatment . Although a series of two‐dimensional (2D) and three‐dimensional (3D) COFs connected by covalent boronate, hydrazone, imine, ether, and olefin linkages have been reported so far, only a handful of COFs have been successfully scaled down to the nanoregime. However, some unique advantages possessed by nanoscale COFs (NCOFs) make them more suitable for biomedical applications (Figure ), as exemplified here by LZU‐1 …”

Semiconductor/Covalent‐Organic‐Framework Z‐Scheme Heterojunctions for Artificial Photosynthesis

“…Polyarylether-(PAE)-COFs are aclass of COFs that are condensed through aromatic nucleophilic substitution between various o-difluorobenzene and catechol building blocks. [11] We chose 2,3,6,7,10, and tetrafluorophthalonitrile (TFPN) or 2,3,5,6-tetrafluoro-4-pyridinecarbonitrile (TFPC) as precursors to obtain two PA E-COFs,n amed COF-316 and COF-318, respectively.T he strong electron-withdrawing substituents on the TFPN and TFPC building blocks make TFPN/TFPC prone to nucleophilic attacks by hydroxyl functionalities. [12] It is well known that various semiconductors can be functionalized by organic functional groups through covalent linking, especially oxidesemiconductors,w hich always contain hydroxyl functional groups on the surface.…”

Semiconductor/Covalent‐Organic‐Framework Z‐Scheme Heterojunctions for Artificial Photosynthesis

“…In this work, we present a method for the fabrication of stable covalently linked organic–inorganic Z‐scheme systems comprising COFs and inorganic oxide semiconductors for artificial photosynthesis (CO 2 RR with H 2 O). Polyarylether(PAE)‐COFs are a class of COFs that are condensed through aromatic nucleophilic substitution between various o ‐difluorobenzene and catechol building blocks . We chose 2,3,6,7,10,11‐hexahydroxytriphenylene (HHTP) and tetrafluorophthalonitrile (TFPN) or 2,3,5,6‐tetrafluoro‐4‐pyridinecarbonitrile (TFPC) as precursors to obtain two PAE‐COFs, named COF‐316 and COF‐318, respectively.…”