title: Efficient removal of organic ligands from supported nanocrystals by fast thermal annealing enables catalytic studies on well-defined active phases.
abstract: A simple yet efficient method to remove organic ligands from supported nanocrystals is reported for activating uniform catalysts prepared by colloidal synthesis procedures. The method relies on a fast thermal treatment in which ligands are quickly removed in air, before sintering can cause changes in the size and shape of the supported nanocrystals. A short treatment at high temperatures is found to be sufficient for activating the systems for catalytic reactions. We show that this method is widely applicable to nanostructures of different sizes, shapes, and compositions. Being rapid and effective, this procedure allows the production of monodisperse heterogeneous catalysts for studying a variety of structure-activity relationships. We show here results on methane steam reforming, where the particle size controls the CO/CO2 ratio on alumina-supported Pd, demonstrating the potential applications of the method in catalysis.
authors.affiliation: †Department of Chemistry, ‡Department of Chemical and Biomolecular Engineering, and §Department of Materials Science and Engineering, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States.
authors.forename: Matteo
authors.initials: M
authors.lastname: Cargnello
authors.affiliation: †Department of Chemistry, ‡Department of Chemical and Biomolecular Engineering, and §Department of Materials Science and Engineering, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States.
authors.forename: Chen
authors.initials: C
authors.lastname: Chen
authors.affiliation: †Department of Chemistry, ‡Department of Chemical and Biomolecular Engineering, and §Department of Materials Science and Engineering, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States.
authors.forename: Benjamin T
authors.initials: BT
authors.lastname: Diroll
authors.affiliation: †Department of Chemistry, ‡Department of Chemical and Biomolecular Engineering, and §Department of Materials Science and Engineering, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States.
authors.forename: Vicky V T
authors.initials: VV
authors.lastname: Doan-Nguyen
authors.affiliation: †Department of Chemistry, ‡Department of Chemical and Biomolecular Engineering, and §Department of Materials Science and Engineering, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States.
authors.forename: Raymond J
authors.initials: RJ
authors.lastname: Gorte
authors.affiliation: †Department of Chemistry, ‡Department of Chemical and Biomolecular Engineering, and §Department of Materials Science and Engineering, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States.
authors.forename: Christopher B
authors.initials: CB
authors.lastname: Murray