“Suspended” Pt nanoparticles over TiO2 nanotubes for enhanced photocatalytic H2 evolution

Abstract

In the present work we introduce a technique to form a photocatalyst based on Pt nanoparticles suspended over the mouth of anodic TiO₂ nanotubes. These structures are obtained by decorating the top end of highly ordered TiO₂ nanotubes with a web of TiO₂ nanofibrils, followed by sputter deposition of a minimum amount of Pt. A subsequent thermal dewetting step forms 3–6 nm-sized Pt nanoparticles along the nanofibrils. These structures, when compared to conventional Pt decoration techniques of TiO₂ nanotubes, show strongly enhanced photocatalytic H₂ evolution efficiency.