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Indexed by:期刊论文

Date of Publication:2014-10-01

Journal:MICROPOROUS AND MESOPOROUS MATERIALS

Included Journals:SCIE、EI

Volume:197

Page Number:324-330

ISSN No.:1387-1811

Key Words:Core-shell catalyst; Noble metal catalyst; Mesoporous silica; Metal-organic frameworks; Hydrogenation

Abstract:The work reports a new hierarchically core-shell structure that consists of a catalytically active core made of palladium-decorated mesoporous silica spheres (Pd/MSS) and an outer shell of microporous ZIF-8. The synthesis process involves (i) the preparation of MSS via supramolecular templating using a modified Stober method, (ii) the loading of palladium nanoparticles into MSS, followed by (iii) the surface modification of Pd/MSS catalyst with polyelectrolyte to promote the nucleation and growth of a ZIF-8 shell. The core-shell Pd/MSS@ZIF-8 was characterized by X-ray diffraction, electron microscopy (SEM & TEM), FTIR, ICP-AES and N-2 physisorption to determine its physicochemical properties. The core-shell Pd/MSS@ZIF-8 was used to catalyze the hydrogenation of 1-hexene and cyclohexene. Results showed that the Pd/MSS@ZIF-8 was a multifunctional catalyst with excellent reactant shape-selectivity, leaching-proof ability, improved poison resistance and good recyclability in contrast to the conventional Pd/MSS catalyst. (C) 2014 Elsevier Inc. All rights reserved.