Synthesis and characterization of osmium(0) nanoclusters and their catalytic use in aerobic alcohol oxidation

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2011

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Akbayrak, Serdar

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Transition metal nanoclusters are more active and selective catalysts than their bulk counterparts as the fraction of surface atoms increases with the decreasing particle size. When stabilized in organic or aqueous solutions, they can catalyze many reactions. The catalytic activity of metal nanoclusters depends on the particle size and size distribution. Particle size can be controlled by encapsulating the nanoclusters in the cavities of highly ordered porous materials such as zeolites. In this project, osmium(0) nanoclusters were formed within the void spaces of zeolite. Thus, nanoclusters of certain size were prepared as supported catalyst. Osmium(III) cations were introduced into the cavities of zeolite by ion exchange and were reduced partially or completely to form intrazeolite osmium(0) nanoclusters. The intrazeolite osmium(0) nanocusters were characterized by HRTEM, TEM, EDX, XPS, XRD, ICP-OES spectroscopic methods and N2 adsorption-desorption technique. Intrazeolite osmium(0) nanoclusters were employed as catalyst in the aerobic oxidation of alcohols in organic solution.

Subject Keywords

Chemistry, Inorganic., Osmium.

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http://etd.lib.metu.edu.tr/upload/12612953/index.pdf
https://hdl.handle.net/11511/20460

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Graduate School of Natural and Applied Sciences, Thesis

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Citation Formats

S. Akbayrak, “Synthesis and characterization of osmium(0) nanoclusters and their catalytic use in aerobic alcohol oxidation,” M.S. - Master of Science, Middle East Technical University, 2011.