Effect of HCl on the structure and catalytic activity of Pt/Al2O3 nanocatalyst prepared in microemulsion system

Document Type : Article

Authors

1 Department of Chemistry, Faculty of Science, Arak University, Arak, 38156-8-8349, Iran.

2 Department of Chemistry, Faculty of Science, Arak University, Arak, 38156-8-8349, Iran.; Institute of Nanosciences & Nanotechnolgy, Arak University, Arak, 8156-8-8349, Iran

Abstract

Now a day preparation of special and effective nanocatalysts is a hot research topic. Obviously the size and structure of the active site of a catalyst plays the key role in catalytic activity. In this novel research the Pt nanocatalyst supported on γ-Al2O3 was prepared in two different microemulsion systems to clarify the effect of microemulsion essence on catalyst character and activity. Two types of microemulsion systems were constructed from Triton X-100/2-butanol as surfactant and co-surfactant, n-heptane as organic phase and H2O + H2PtCl6 (or HCl(aq) + H2PtCl6) as aqueous phase to investigate the effect of HCl on the shape and structure of the prepared nanocatalysts. Shape, size and size distribution of the Pt nanoparticles on the alumina were monitored by cyclic voltammetry and SEM analysis. Activity of the nanocatalysts was determined by reduction of p-nitrophenol as a reaction model.

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Main Subjects


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