Covalent Organic Frameworks with Ionic Liquid-Moieties (ILCOFs): Structures, Synthesis, and CO2 Conversion

Abstract

CO2, an acidic gas, is usually emitted from the combustion of fossil fuels and leads to the formation of acid rain and greenhouse effects. CO2 can be used to produce kinds of value-added chemicals from a viewpoint based on carbon capture, utilization, and storage (CCUS). With the combination of unique structures and properties of ionic liquids (ILs) and covalent organic frameworks (COFs), covalent organic frameworks with ionic liquid-moieties (ILCOFs) have been developed as a kind of novel and efficient sorbent, catalyst, and electrolyte since 2016. In this critical review, we first focus on the structures and synthesis of different kinds of ILCOFs materials, including ILCOFs with IL moieties located on the main linkers, on the nodes, and on the side chains. We then discuss the ILCOFs for CO2 capture and conversion, including the reduction and cycloaddition of CO2. Finally, future directions and prospects for ILCOFs are outlined. This review is beneficial for academic researchers in obtaining an overall understanding of ILCOFs and their application of CO2 conversion. This work will open a door to develop novel ILCOFs materials for the capture, separation, and utilization of other typical acid, basic, or neutral gases such as SO2, H2S, NOx, NH3, and so on.

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“…90 Therefore, ILs are regarded as effective crystal growth modifiers for tuning the construction of both organic and inorganic materials with diverse crystal phases and morphologies. 91–94 As shown in Fig. 12a, there are abundant defects in the surface of the MoS 6 catalyst after ILs-modification and Fig.…”

Significance of Various Sensing Mechanisms for Detecting Local and Atmospheric Greenhouse Gases: A Review

“…Highlighted in the sections above, a vast array of traditional, novel, and hybrid complex materials have been uncovered and adopted within the frameworks of sensors dedicated toward detecting GHGs. These include the carbon nanomaterials, polymers, metal oxide semiconductors, and transition metal dichalcogenides, in calorimetric sensors; [102,108,117,122]] the solid polymer electrolytes, pseudo-solid-state electrolytes, and carbon materials, in electrochemical sensors; [67][68][69]109,121,133,137]] pyroelectric elements, LEDs, and PDs, in IR/FTIR/NDIR sensors; [72][73][74][75][76]78,84,85,109,131]] metal oxides, carbon materials, polymers, and single-or multi-mode optical fibers, in opticalbased sensors; [86][87][88][89][90][92][93][94]109,134]] piezoelectric materials, piezoceramics, carbon materials, and polymers, in acoustic/ultrasonic sensors; [91,[95][96][97][98][99]100,110,111] as well as polymer films in calorimetric or gas chromatographic sensors. [103,104,…”

“…As they pertain to GHG detection, COFs have been explored rather recently, and in works reported by Zhang et al., COFs with ionic liquid‐moieties, or ILCOFs, were determined to facilitate the capture and conversion (e.g., cycloaddition and reduction) of CO 2 . [ 137 ] The COFs applied in works integrating them with ionic liquids were prepared using a series of elements (including, metalloporphyrins) with pyridinium, imidazolium, guanidinium, spiroborate, squaraine linkers coordinating the ILCOFs structures. In records prepared by Zeng et al., COFs containing boron and oxygen bonds (B‐O), namely, B 3 O 3 (boroxine) and C 2 O 2 B (boronate), as well as triazine‐based, imine‐based, and boron/imine‐based COFs were all reported to be useful in CO 2 capture.…”

Quaternary Ammonium-Functionalized Mesoporous Covalent Organic Frameworks for Effective Catalytic CO2 Cycloaddition

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