In the preparation of 1% Au/TiO2 catalysts supported on either Degussa P-25 or anatase (90 m(2) g(-1)) by deposition-precipitation, the gold content passes through a maximum at about the isoelectric point (pH similar to 6), but maximum specific rates occur at pH 8-9 because the Au particle size becomes smaller as the pH is further increased. The gold uptake increases with the surface area of the support (anatase, rutile, P-25) and is complete above 200 m(2) g(-1); adsorption of the gold precursor at pH 9 is shown to be equilibrium-limited. Highest activities are found with supports of similar to 50 m(2) g(-1). Catalysts made with high-area anatase (240 or 305 m2 g(-1)) are least active but show least deactivation.With Au/SnO2 catalysts, gold uptake does not depend on the area of the support, and is highest at pH 7-8; very active catalysts (T-50 = 230-238 K) are obtained using SnO2 of 47 m(2) g(-1). Storing a catalyst at 258 K for 1 week dramatically improves its stability. Results for Au/CeO2 and Au/ZrO2 catalysts confirm that moderate support areas give the most active catalysts, and suggest that surface area is often more important than chemical composition. (C) 2006 Elsevier B.V. All rights reserved.