Creating amphiphilic porosity in two-dimensional covalent organic frameworks via steric-hindrance-mediated precision hydrophilic-hydrophobic microphase separation.

Creating different pore environments within a covalent organic framework (COF) will lead to useful multicompartment structure and multiple functions, which however has been scarcely achieved. Herein we report designed synthesis of three two-dimensional COFs with amphiphilic porosity by steric-hindrance-mediated precision hydrophilic-hydrophobic microphase separation. Dictated by the different steric effect of the substituents introduced to a monomer, dual-pore COFs with kgm net, in which all hydroxyls locate in trigonal micropores while hydrophobic sidechains exclusively distribute in hexagonal mesopores, have been constructed to form completely separated hydrophilic and hydrophobic nanochannels.

One-Dimensional Covalent Organic Framework as High-Performance Cathode Materials for Lithium-Ion Batteries.

Covalent organic frameworks (COFs) have emerged as a new class of cathode materials for energy storage in recent years. However, they are limited to two-dimensional (2D) or three-dimensional (3D) framework structures. Herein, this work reports designed synthesis of a redox-active one-dimensional (1D) COF and its composites with 1D carbon nanotubes (CNTs) via in situ growth.

Boosting Hydrostability and Carbon Dioxide Capture of Boroxine-Linked Covalent Organic Frameworks by One-Pot Oligoamine Modification.

Boron-based covalent organic frameworks (COFs) are susceptible to nucleophilic attack by water at the electron-deficient boron sites and even slightly humid air could destroy the integrity of their porous frameworks within hours. Such instability is a major limitation to the practical applications of boron-based COFs. Herein we report a significant enhancement of hydrostability of boroxine-linked COFs (COF-1 as representative) by modification with an oligoamine (tetraethylenepentamine, TEPA), which leads to survival of the modified COF in water and long-time stability under humid atmosphere.

A Superhydrophobic Trifluoromethyl-Containing Covalent Organic Framework Membrane for Efficient Oil/Water Separation.

Oily water caused in the process of industry leads to not only the waste of resources, but also environmental pollution. Membrane separation, as a facile and efficient separation technology, has attracted widespread attention in the field of oil/water separation. The development of membrane materials with high separation performance is one of the key elements to improve separation efficiency.

A facile and scalable synthetic method for covalent organic nanosheets: ultrasonic polycondensation and photocatalytic degradation of organic pollutants.

Covalent organic framework nanosheets (COF NSs or CONs), as compared to their bulk counterparts two-dimensional (2D) covalent organic frameworks (COFs), exhibit superior performance in many aspects due to their fully accessible active sites benefiting from their ultrathin porous 2D structures. The development of a scalable synthetic methodology for CONs is crucial to further exploration of their unique properties and practical applications. Herein, we report an efficient strategy to fabricate ultrathin CONs through direct polycondensation of monomers under ultrasonic treatment and mild conditions.

A Facile, Efficient, and General Synthetic Method to Amide-Linked Covalent Organic Frameworks.

Amide-linked covalent organic frameworks (amide COFs) possess enormous potentials in practical applications benefiting from their high stability and polyamide structures. However, they suffer from very limited accessibility. Herein, we report a new linkage conversion method to rapidly synthesize crystalline amide COFs through oxidation of imine linkages in their corresponding imine-linked frameworks with KHSO as an oxidant under very mild conditions.

Aminal-Linked Covalent Organic Frameworks through Condensation of Secondary Amine with Aldehyde.

New linkage chemistry will endow covalent organic frameworks (COFs) with not only structural diversity but also fascinating properties. However, to develop a new type of linkages has been a great challenge. We herein report the first two COFs using aminal as the linkages.

A gaseous hydrogen chloride chemosensor based on a 2D covalent organic framework.

A tetraphenylethene-based 2D covalent organic framework (COF) has been synthesized. It exhibits a very fast response and high sensitivity to the presence of gaseous HCl by way of distinct changes in fluorescence emission and color, which makes the COF a good chemosensor for spectroscopic and naked-eye detection of gaseous HCl.