Gold nanoparticles supported on ionic-liquid-functionalized cellulose (Au@CIL): A heterogeneous catalyst for the selective reduction of aromatic nitro compounds

In response to the increasing need for green and cost-effective catalysts, a novel biomass-derived heterogeneous catalyst that is effective in a number of environmentally friendly applications has been synthesized. The heterogeneous catalyst (Au@CIL), composed of ionic-liquid-functionalized cellulose embedded with Au nanoparticles (NPs), was developed for the selective reduction of the nitro group. The Au NPs are formed by the reduction of Au³⁺ to Au⁰ with ascorbic acid while embedded in the solid support system. The presence of embedded Au NPs was confirmed using infrared spectroscopy, powder X-ray diffraction, scanning electron microscopy, zeta-potential measurements, energy-dispersive X-ray analysis, elemental dot mapping, and atomic force microscopy. In water at 30 °C, the heterogeneous catalyst Au@CIL selectively transforms aromatic nitro compounds into the corresponding amines in the presence of other functional groups, such as hydroxy, amino, aldehyde, carboxylic acid, and amide.