Bottom-up approaches for the synthesis of nanostructured heterogeneous (electro-) catalysts, via the colloidal deposition route combined with nanostructured catalyst supports, have been investigated in this thesis. Colloidal gold nanoparticles have been selected as a case study in view of their promising catalytic properties for oxidation reactions, as well as their ability to convert carbon dioxide to carbon monoxide under electrocatalytic conditions. Benzyl alcohol aerobic oxidation was selected as a test reaction of choice to characterize the catalytic properties of the colloidal gold nanoparticles under investigation, in view of the extensive literature available on this topic. Furthermore, practical experience with this reaction and colloidal gold nanoparticles had already been gained in the Catalysis Engineering group, reflected by a previous publication involving dodecylamine-capped gold nanoparticles...@en

To prevent sintering, ozone treatment at mild temperature is used to remove the capping agent from supported Au nanoparticles. The Au nanoparticles are first synthesized as a colloidal solution and then supported on alumina. Fourier Transform Infra Red (FTIR) shows the capping agent is removed completely. Transmission Electron Microscopy (TEM) and catalytic test reactions show the Au does not sinter significantly upon low temperature ozone treatment.

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