Palladium(0) nanoparticles supported on a polymeric membrane, CA/Pd(0), were found to be a highly efficient “dip catalyst” (heterogeneous catalyst) for Suzuki–Miyaura cross-coupling reactions. Iodo-, bromo- and electron-poor chloroarenes coupled with phenylboronic acid under eco-friendly conditions (i.e., phosphine-free and with water as the solvent) to give excellent yields. The CA/Pd(0) was prepared initially via the synthesis of Pd(0) by hydrogen decomposition of Pd(acac)₂ dissolved in BMI·BF₄ ionic liquid at 75 °C for 1.0 hour to yield a black suspension (nanoparticles with a diameter of 2.7 ± 0.4 nm). These nanoparticles were washed with acetone and dried under reduced pressure. The Pd(0) nanoparticles were subsequently added to a cellulose acetate solution with acetone to generate the CA/Pd(0) polymeric membrane. The CA/Pd(0) “dip catalyst” was characterised by X-ray diffraction (XRD), scanning electron microscopy (SEM), electron-dispersive spectroscopy (EDS) and transmission electron microscopy (TEM).

Platinum nanoparticles (ca. 2.3 nm) dispersed in ionic liquids and functionalized ionic liquids were supported within a silica network by the sol–gel method. The effect of the sol–gel catalyst (acid or base) on the encapsulated ionic liquid and on the platinum content was studied, and the silica morphology, the texture of the support material, and the hydrogenation activity were investigated. The Pt(0) content in the resulting xerogels (ca. 0.2 wt% Pt/SiO₂) was shown to be independent of the sol–gel process. The acidic conditions resulted in xerogels with larger pore diameters, which in turn might be responsible for the higher catalytic activity in hydrogenation of the alkenes and arenes obtained with the heterogeneous catalyst (Pt(0)/SiO₂).

Iridium nanoparticles (Ir(0) NPs) of 2.1 ± 0.5 nm were synthesized from [Ir(cod)Cl]₂(cod = 1,5-cyclooctadiene) in the ionic liquid (IL) 1-n-butyl-3-methylimidazolium hexafluorophosphate [BMI.PF₆].

TiO ₂ nanoparticles were synthesized using 1- n -butyl-3-methylimidazolium tetrafluoroborate (BMI·BF ₄ ) ionic liquid and doped with non-expensive metals Cu ²⁺ and Fe ³⁺ by the sol–gel method.