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    Ceria/silicon carbide core–shell materials prepared by miniemulsion technique
    (Frankfurt, M. : Beilstein-Institut zur Förderung der Chemischen Wissenschaften, 2011) Borchardt, Lars; Oschatz, Martin; Frind, Robert; Kockrick, Emanuel; Lohe, Martin R.; Hauser, Christoph P.; Weiss, Clemens K.; Landfester, Katharina; Büchner, Bernd; Kaskel, Stefan
    For the first time we present the synthesis of CeO2/Si(O)C core–shell particles prepared by the miniemulsion technique. The Si(O)C core was obtained by means of a polycarbosilane precursor (SMP10), which was subsequently functionalized with ceria and pyrolyzed to the ceramic. The size of these particles could easily be adjusted by varying the surfactants and the surfactant concentration, or by the addition of comonomers. Hence particle sizes ranged from 100 to 1000 nm, tunable by the preparation conditions. All materials were characterized by photon cross correlation spectroscopy, scanning electron microscopy and elemental mapping investigations. Furthermore, first catalytic tests were carried out by temperature programmed oxidation (TPO) of methane, and the activity of this material in lowering the onset temperature of methane combustion by 262 K was documented.
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    Mechanochemistry-assisted synthesis of hierarchical porous carbons applied as supercapacitors
    (Frankfurt, M. : Beilstein-Institut zur Förderung der Chemischen Wissenschaften, 2017) Leistenschneider, Desirée; Jäckel, Nicolas; Hippauf, Felix; Presser, Volker; Borchardt, Lars
    A solvent-free synthesis of hierarchical porous carbons is conducted by a facile and fast mechanochemical reaction in a ball mill. By means of a mechanochemical ball-milling approach, we obtained titanium(IV) citrate-based polymers, which have been processed via high temperature chlorine treatment to hierarchical porous carbons with a high specific surface area of up to 1814 m2 g−1 and well-defined pore structures. The carbons are applied as electrode materials in electric double-layer capacitors showing high specific capacitances with 98 F g−1 in organic and 138 F g−1 in an ionic liquid electrolyte as well as good rate capabilities, maintaining 87% of the initial capacitance with 1 M TEA-BF4 in acetonitrile (ACN) and 81% at 10 A g−1 in EMIM-BF4.