title: Imidazolium-Functionalized Carbon Nanohorns for the Conversion of Carbon Dioxide: Unprecedented Increase of Catalytic Activity after Recycling.
abstract: Six new hybrid materials composed of carbon nanohorns (CNHs) and highly cross-linked imidazolium salts were easily synthesized using a one-step procedure based on the radical oligomerization of bis-vinylimidazolium salts (bVImiX) in the presence of pristine CNHs. The hybrid materials were characterized and employed as the sole catalysts for the conversion of carbon dioxide into cyclic carbonate by reaction with epoxides. The solids displayed excellent turnover number and productivity. Moreover, four catalysts were investigated in recycling experiments. Two catalysts containing an octyl linker between the imidazolium units and a bromide or an iodide anion showed no loss in activity after three cycles. The other two catalysts containing a p-xylyl linker and a bromide anion and different CNHs/bVImiX ratios showed an unprecedented increase of activity after recycling.
authors.affiliation: Department of Biological, Chemical and Pharmaceutical Sciences and Technologies, University of Palermo, Viale delle Scienze, Ed. 17, 90128, Palermo, Italy.|Laboratory of Applied Material Chemistry (CMA), University of Namur, 61 rue de Bruxelles, 5000, Namur, Belgium.
authors.forename: Carla
authors.initials: C
authors.lastname: Calabrese
authors.affiliation: Istituto per lo Studio dei Materiali Nanostrutturati, ISMN-CNR via Ugo La Malfa 153, 90146, Palermo, Italy.
authors.forename: Leonarda F
authors.initials: LF
authors.lastname: Liotta
authors.affiliation: Laboratory of Applied Material Chemistry (CMA), University of Namur, 61 rue de Bruxelles, 5000, Namur, Belgium.
authors.forename: Esther
authors.initials: E
authors.lastname: Carbonell
authors.affiliation: Department of Biological, Chemical and Pharmaceutical Sciences and Technologies, University of Palermo, Viale delle Scienze, Ed. 17, 90128, Palermo, Italy.
authors.forename: Francesco
authors.initials: F
authors.lastname: Giacalone
authors.affiliation: Department of Biological, Chemical and Pharmaceutical Sciences and Technologies, University of Palermo, Viale delle Scienze, Ed. 17, 90128, Palermo, Italy.
authors.forename: Michelangelo
authors.initials: M
authors.lastname: Gruttadauria
authors.affiliation: Laboratory of Applied Material Chemistry (CMA), University of Namur, 61 rue de Bruxelles, 5000, Namur, Belgium.
authors.forename: Carmela
authors.initials: C
authors.lastname: Aprile
mesh_terms: D002245:Carbon Dioxide / Q000737:chemistry*; D002384:Catalysis; D004852:Epoxy Compounds / Q000737:chemistry; D007093:Imidazoles / Q000737:chemistry*; D037742:Nanotubes, Carbon / Q000737:chemistry*; D059027:Recycling
chemical_list: D004852:Epoxy Compounds; D007093:Imidazoles; D037742:Nanotubes, Carbon; D002245:Carbon Dioxide; C029899:imidazole
keywords: carbon dioxide conversion; carbon nanohorns; cyclic carbonates; heterogeneous catalysis; imidazolium salts