title: Synthesis, assembly and reaction of a nanocatalyst in microfluidic systems: a general platform.
abstract: We present a successive microfluidic approach to create and characterize hierarchical catalyst structures consisting of metal-decorated nanoparticles that are assembled into porous microparticles ("supraball" catalysts). First, using a silicon microreactor, platinum nanoparticles with a very narrow size distribution are grown and immobilized uniformly onto iron oxide/silica core-shell nanospheres. The Pt-decorated silica nanospheres are then assembled into uniform, spherical, micron-sized particles by using emulsion templates generated with a microfluidic drop generator. Finally, the assembled supraballs are loaded into a packed-bed microreactor for characterization of the catalytic reactivity. The prepared material showed excellent catalytic activity for the oxidation of aldehyde with only ~1 mg of material (containing ~50 μg of platinum nanoparticles). After the reactions, all the supraball catalysts are recovered by using the magnetic property of the underlying iron oxide/silica core-shell nanospheres.
authors.affiliation: Department of Chemical Engineering, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139, USA.
authors.forename: Seung-Kon
authors.initials: SK
authors.lastname: Lee
authors.forename: Xiaoying
authors.initials: X
authors.lastname: Liu
authors.forename: Víctor
authors.initials: V
authors.lastname: Sebastián Cabeza
authors.forename: Klavs F
authors.initials: KF
authors.lastname: Jensen
mesh_terms: D000447:Aldehydes / Q000737:chemistry*; D002384:Catalysis; D004655:Emulsions; D005290:Ferric Compounds / Q000737:chemistry*; D053768:Metal Nanoparticles / Q000737:chemistry*; D046210:Microfluidic Analytical Techniques / Q000295:instrumentation / Q000379:methods*; D054118:Nanospheres / Q000737:chemistry*; D010084:Oxidation-Reduction; D010984:Platinum / Q000737:chemistry*; D012825:Silicon / Q000737:chemistry
chemical_list: D000447:Aldehydes; D004655:Emulsions; D005290:Ferric Compounds; C000499:ferric oxide; D010984:Platinum; D012825:Silicon