Synthesis of High Surface Area TiO2 Aerogel Support with Pt Nanoparticle Catalyst and CO Oxidation Study

Abstract

We demonstrate the preparation and catalytic testing of nanocatalysts composed of TiO2 synthesized in aerogel using a supercritical drying process with Pt nanoparticles deposited on the mesopore oxide surface. By controlling the aging time, we found conditions that led to TiO2 with a surface area among the highest ever reported for a TiO2 material in aerogel form (similar to 685 m(2) g(- 1)). The chosen synthesis route also features good control over the pore volume and pore size. Even though our aerogel TiO2 support showed an amorphous structure before calcination, 90.2% anatase and 9.8% rutile phases co-existed after calcination at 500 A degrees C for 2 h with an average particle size of about 17 nm based on XRD results. The as-synthesized TiO2 and Pt/TiO2 were both used as catalysts for the CO oxidation reaction. Uncalcined Pt/TiO2 showed 100% conversion at 300 A degrees C. After calcination, Pt/TiO2 exhibited a significantly higher catalytic activity, showing 100% conversion at 125 A degrees C and an activation energy of only 13.4 kcal mol(- 1). We show that TiO2 synthesized by the aerogel method can be an excellent support material for nanocatalysis because of its high surface area and facile and scalable synthesis. [GRAPHICS] .