Triazole-based COF tightly hugging ionic liquids through interactions of hydrogen bonds for enhanced atmospheric CO₂ conversion

In the conversion of CO₂ into green chemicals, efficient catalysts are urgently needed. Composite catalysts with ionic liquids (ILs) fixed to covalent organic frames (COFs) are considered as ideal materials. However, synthesizing composite materials by modifying ionic liquids on covalent organic frameworks encountered challenges related to the modification process and the easy detachment of functional groups. In this paper, a variety of multifunctional components were combined into composites to tailor catalysts ([TMGVBr]_x@COFs) for cycloaddition reaction under mild atmospheric CO₂ condition. In the strategy of in-situ encapsulation, triazole-based COF (TT-COF) tightly “hugged” the ionic liquids ([TMGH⁺][^-O₂MVIm⁺][Br^-]) through the inductions of hydrogen bonds, resulting in excellent stability. Moreover, owing to the synergy between [TMGH⁺][^-O₂MVIm⁺][Br^-] and TT-COF, [TMGVBr]₁₀@COF achieved a good catalytic activity with 96.3 % yield in the cycloaddition reactions under atmospheric CO₂, 100 °C and 10 h. Furthermore, the strong hydrogen bonds between ionic liquids and the framework of TT-COF ensured the [TMGVBr]₁₀@COF catalyst's good catalytic stability. There, a new idea was proposed for the efficient conversion atmospheric CO₂ using designed heterogeneous catalysts.