title: Stable and water-tolerant ionic liquid ferrofluids.
abstract: Ionic liquid ferrofluids have been prepared containing both bare and sterically stabilized 8-12 nm diameter superparamagnetic iron oxide nanoparticles, which remain stable for several months in both protic ethylammonium and aprotic imidazolium room-temperature ionic liquids. These ferrofluids exhibit spiking in static magnetic fields similar to conventional aqueous and nonaqueous ferrofluids. Ferrofluid stability was verified by following the flocculation and settling behavior of dilute nanoparticle dispersions. Although bare nanoparticles showed excellent stability in some ILs, they were unstable in others, and exhibited limited water tolerance. Stability was achieved by incorporating a thin polymeric steric stabilization layer designed to be compatible with the IL. This confers the added benefit of imbuing the ILF with a high tolerance to water.
authors.affiliation: School of Chemistry and Key Centre for Polymers and Colloids, The University of Sydney, New South Wales 2006, Australia.
authors.forename: Nirmesh
authors.initials: N
authors.lastname: Jain
authors.forename: Xiaoli
authors.initials: X
authors.lastname: Zhang
authors.forename: Brian S
authors.initials: BS
authors.lastname: Hawkett
authors.forename: Gregory G
authors.initials: GG
authors.lastname: Warr
mesh_terms: D005290:Ferric Compounds / Q000737:chemistry*; D057927:Hydrophobic and Hydrophilic Interactions; D052578:Ionic Liquids / Q000737:chemistry*; D008280:Magnetics; D008422:Materials Testing; D014867:Water / Q000737:chemistry*
chemical_list: D005290:Ferric Compounds; D052578:Ionic Liquids; D014867:Water; C000499:ferric oxide