Preparation and catalysis of gold nanoparticles deposited on nanosized titania particles

Nanosized anatase (< 10 nm), rutile ( ≤ 10 nm), and brookite (≈ 70 nm) titania particles were successfully synthesized via sonication and hydrothermal methods. Metallic gold nanoparticles were uniformly deposited on the surface of nanosized particles of as-synthesized anatase, rutile, and brookite and commercial titania P25 supports through a deposition-precipitation process. Catalysis experiments on CO oxidation indicated that the as-synthesized P25-supported Au catalyst showed the highest initial activity. The significant deactivations of all four catalysts under reaction conditions were observed. Catalysis results also showed that the as-synthesized anatase, rutile, and brookite nanoparticles are better supports than commercial P25 by providing high catalytic stability under reaction conditions/treatments. The brookite-supported gold catalyst gave the highest catalytic stability under all reaction conditions. XRD results indicated that the gold particles supported on anatase, rutile, and P25 are much bigger than those supported on brookite after catalytic reactions. This is an abstract of a paper presented at the 228th ACS National Meeting (Philadelphia, PA, 8/22-26/2004).