Highly Performing Imidazolium Functionalized Carbon Nanohorns for the Conversion of Carbon Dioxide. Unprecedented Increase of

Six new hybrid materials, constituted by carbon nanohorns and highly cross-linked imidazolium salts, were easily synthesized via a one-step procedure based on radical oligomerization of bisvinylimidazolium salts (bVImiX) in the presence of pristine carbon nanohorns (CNHs). Such 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 TON and productivity. Moreover, four catalysts were investigated in recycling experiments. Two catalysts having an octyl linker between the imidazolium units and bromide or iodide anion showed no loss in activity after three cycles. Other two catalysts having a p-xylyl linker and bromide anion and different CNHs/bVImiX ratio showed an unprecedented increase of activity after recycling.