Bifunctional mesoporous organic-inorganic hybrid silica involving platinum and propylsulfonic acid groups (Pt/SBA15-PrSO(3)H) have been demonstrated to have potential for catalyzing the combined one-step hydrogenation/esterification (OHE) reaction. This reaction provides a model system for the catalytic upgrading of biomass-derived bio-oil. In this study, efforts were made to improve the catalytic performance of the catalyst for aldehyde hydrogenation, which was determined to be rate limiting in the ONE reaction with the bifunctional catalyst. STEM analysis coupled with hydrogen chemisorption results showed that aqueous reduction-deposition using formaldehyde as the reducing agent produced highly dispersed platinum nanoparticles located within the mesopores of SBA15. XPS and UV-vis demonstrated that the metal sites were not fully activated due to insufficient reducing capability of the formaldehyde. Elevated temperature treatment of the as-prepared materials in either an air or H(2) environment was examined. These treatments significantly increased the acetaldehyde hydrogenation activity, especially in the case of H(2) treatment. XPS and H(2)-TPD results demonstrated that Pt species were further reduced and as a result, hydrogen was activated more readily. (C) 2011 Elsevier B.V. All rights reserved.