Supported gold catalysts prepared by in situ reduction technique: Preparation, characterization and catalytic activity measurements

The low temperature (in situ) reduction of gold ions held on the surface of a suitable metal oxide support, by a strong reducing agent oxide facilitates the formation of embedded gold nanoparticles on that oxide support in such a fashion that, in comparison with other techniques, produces a more narrow size distribution and smaller particle size. Using titania as a the support, Raman spectra provide evidence for the modification of the TiO₂ surface. The strongest E_g mode at 145cm^-1, arising from the extension vibration of the anatase structure has been perturbed by the introduction of nanosized gold particles. The rate of oxidation of carbon monoxide in the present work for the Au-TiO₂, corresponds to a turnover frequency of 0.1s^-1 for reaction at 40°C based on a gold dispersion of 0.6 estimated on the basis of a mean particle size as determined by means of high-resolution transmission electron microscopy (HRTEM).