Keywords:Palladium Direct synthesis of hydrogen peroxide Titanium dioxide Anatase SMSI (strong metalesupport interaction) a b s t r a c t In this study, titania-supported Pd catalysts were prepared and their performance evaluated upon H 2 O 2 direct synthesis. Typically, the materials contained different ratios of anatase and rutile phases, which gave rise to different surface properties of the supports, e.g., surface area, number of Lewis acidic and basic sites as well as different compositions of the phases, i.e. the amount of anatase phase and crystallite size. Two materials, Pd-A98 and Pd-A05 samples, respectively, apparently hint the existence of the so-called SMSI (strong metalesupport interaction) phenomenon giving rise to 1080 and 683 mol H2O2 $mol Pd À1 $h À1 of H 2 O 2 productivity and 22 and 14% of H 2 O 2 selectivity, respectively.However, the best material, Pd-A82, gave rise to 949 mol H 2 O 2 $mol Pd À1 $h À1 of H 2 O 2 productivity and 26% of H 2 O 2 selectivity.