Rapid Assessment of Sputtered Nanoparticle Ionic Liquid Combinations

A high-throughput method is presented for the efficient assessment of the formation and stability of nanoparticle suspensions in ionic liquids which differ in their cations and anions. As a proof of principle, Ag was sputtered on a cavity array filled with 9 different ionic liquids. Not all nanoparticle ionic liquid combinations form a stable suspension with separated nanoparticles. Directly after synthesis, the formation of nonagglomerated nanoparticle suspensions with sizes from 4 to 9 nm is observed by transmission electron microscopy as well as different time dependencies of the suspension stabilities. Only 3 out of the tested 9 nanoparticle ionic liquid suspensions show long-term stability: Stable suspension of spherical nanoparticles are formed in the ionic liquids 1-butyl-3-methylimidazolium bis­(perfluoroethylsulfonyl)­imide [Bmim]­[(Pf)₂N], 1-butyl-3-methylimidazolium bis­(trifluoromethylsulfonyl)­imide [Bmim]­[(Tf)₂N], and 1-butyl-1-methylpyrrolidinum bis­(trifluoromethylsulfonyl)­imide [BmPyr]­[(Tf)₂N]