Pt nanoparticles on titania nanotubes prepared by vapor-phase impregnation–decomposition method

Platinum (Pt) nanoparticles were prepared on titania nanotubes (TNTs) by vapor-phase impregnation–decomposition method using platinum acetylacetonate as precursor. TNTs and Pt precursor were mixed in 3:1 weight ratio before vapor-phase impregnation. The mixed powders were heated at 453 K for 10 min to evaporate the precursor in a horizontal tube quartz reactor at a total pressure of 66.6 kPa. Then, the impregnated TNTs were moved to a higher temperature zone (673 K) inside the tube reactor to achieve the precursor decomposition. HAADF-STEM observations, AAS and XPS results revealed that this method allows the formation of uniformly distributed Pt nanoparticles on the surface of TNTs with a narrow distribution of particle size (2.1 nm mean size). Pt nanoparticles remain mainly as Pt0 oxidation state with a Pt0/Pt2+ atomic ratio of 3.9.