Ferreira, Tiago J.Cabral, CatarinaCarvalho, Thiago O.Pais, JoanaEsteves, Laura M.Silva, Ludmila P. C.Reis, Patrícia M.Esperança, José M. S. S.Esteves, Isabel A. A. C.2024-10-292024-10-292024-122214-9937PURE: 101209388PURE UUID: e625aec7-e6f4-47d0-bd4a-06d418128d1aScopus: 85204929814WOS: 001328749200001ORCID: /0000-0001-9615-8678/work/170594221ORCID: /0000-0002-2242-6016/work/170594242ORCID: /0000-0002-5458-0448/work/170594430http://hdl.handle.net/10362/174294Publisher Copyright: © 2024 The AuthorsSeveral strategies can be considered for the mitigation of carbon dioxide (CO2) emissions to the atmosphere, and among them is its post-combustion capture/separation from flue gas emitted from coal-fired power plants. In this work, six imidazolium, ammonium- and DABCO-based ionic liquids (ILs) containing the acetate anion were used to impregnate the metal-organic framework (MOF) ZIF-8. The cationic effect was studied to determine how the different cationic families and side alkyl chain size influence the gas sorption performance of the produced IL@MOF composites. The combination of different characterization techniques confirmed IL impregnation, and that the composite materials were microporous and crystalline. Single-component CO2 and nitrogen (N2) sorption-desorption equilibrium measurements were performed at 303 K for ZIF-8 and the IL@ZIF-8 materials. At the low-pressure regime (0–1 bar), synergy was observed for the imidazolium-based composites, especially for the one with the long-side alkyl chain. The ideal CO2/N2 selectivity was calculated for post-combustion composition, and, at 1 bar, [C10MIM][Ac]@ZIF-8 was over four times more selective than ZIF-8, while the selectivity of [C2MIM][Ac]@ZIF-8 at this pressure almost tripled when compared to the MOF. A chemical reaction between CO2 and the imidazolium ILs explained the results.11826192engCationic effectCO post-combustion separationIL@MOF compositesIonic liquid (IL)Metal-organic framework (MOF)Renewable Energy, Sustainability and the EnvironmentGeneral Materials ScienceWaste Management and DisposalIndustrial and Manufacturing EngineeringSDG 7 - Affordable and Clean Energyjournal article10.1016/j.susmat.2024.e01122https://www.scopus.com/pages/publications/85204929814