Fabrication of naked silver nanoparticles in functionalized ionic liquids

Surface clean silver nanoparticles of 5-8 nm in size were prepared in functionalized imidazolium-based ionic liquids containing methoxy, cyano, and thio groups by magnetron sputtering deposition. The surface composition/organization of the ILs controls the size and location of NPs in these fluids. The simple model of metal–ligand interaction of surface-functionalized ILs can be used to explain and predict the structural organization of the sputtered NPs in these fluids. The sputtered NPs tend to penetrate deeper into the regions of the ILs containing lower coordinating groups (OMe), whereas those associated with strong sigma donating groups (CN and SH) tend to place the small nanoparticles close to the liquid surface. We estimate a single monolayer of IL surrounding the smaller Ag NPs located closer to the surface as determined by High-Sensitivity Low-Energy Ion Scattering (HS-LEIS).