Rich-N highly branched COF loaded with imidazolyl ionic liquids for highly efficient catalysis of CO2conversion under atmospheric pressure

Autor: Ge, Yuansheng, Cheng, Guoe, Zou, Yizhen, Ke, Hanzhong
Zdroj: Journal of Environmental Chemical Engineering; December 2024, Vol. 12 Issue: 6
Abstrakt: The highly loaded ionic active centers and carbon dioxide (CO2) affinity sites play pivotal roles in catalyzing the gas-solid-liquid three-phase reaction in CO2cycloaddition. In this study, a kind of rich-N highly branched Covalent organic framework loaded with imidazolyl ionic liquids (DhaTat-COF-IL) was synthesized through a nucleophilic substitution reaction, which bridged the highly loaded imidazolyl ionic liquids (Im-IL) active centers (20.72 %) and strong CO2-philic sites, efficiently promoting the in-situ of CO2conversion at catalyst interface. The rich-N highly branched Covalent organic framework (DhaTat-COF) benefits from its abundant CO2-philic groups (imine and triazine groups) and microporous properties, exhibiting excellent CO2enrichment capacity, designed as a porous crystalline material for anchoring high active Im-IL. The resultant DhaTat-COF-IL achieved a quantitative yield of 95 % (selectivity > 99 %) in converting epichlorohydrin (ECH) under ambient pressure at 80 ℃, with a turnover frequency (TOF) value reaching 1582 h⁻¹ at 120 ℃. Additionally, yields of ≥ 94 % were obtained for various terminal-substituted epoxides. Density Functional Theory (DFT) analysis reveals a synergistic effect between −CH and Br−in the DhaTat-COF-IL during catalytic cycling. This work provides valuable insights into the targeted design and performance optimization of Im-IL-grafted COF-based catalysts, emphasizing high efficiency and sustainability in CO₂ conversion.
Databáze: Supplemental Index