Novel Method for Preparation of Nanostructured Au/TiO2 on SiO2 Support by Colloidal Synthesis

The formation of Au/TiO 2 nanostructured interface on SiO 2 support using Au hydrosol and Ti-isopropoxide or Ti(IV)-bis(ammonium lactato) dihydroxide (TALH) precursors has been investigated in context of preparing a novel type of catalysts active in the CO oxidation. Different preparation routes were compared: (i) Au sol was modified by Ti-precursor then adsorbed on silica followed by calcination, (ii) Au/silica was modified by Ti-precursor and calcined, (iii) Au was deposited on SiO 2 modified by Ti-precursor and calcined. The enhanced catalytic activity in the CO oxidation compared to that of the analogue anatase supported Au catalyst is possibly due to several factors, such as, the morphology of TiO 2 (likely amorphous) and formation of Ti-O-Si interaction, which results in the formation of large and efficient interface between Au and TiO 2 . This was supported by examination of the mechanical mixtures of SiO 2 and anatase supported Au catalysts as well as their modified alternatives.