Plasmonic Pt nanoparticles—TiO2 hierarchical nano-architecture as a visible light photocatalyst for water splitting

摘要

Visible light-driven water splitting (VLWS) into hydrogen and oxygen is attractive and depends on efficient photocatalysts. Herein, we demonstrate the first exploration of the capability to control the morphology of nanostructured TiO2 in conjunction with the choice of a suitable plasmonic metal (PM) to fabricate novel photocatalysts that are capable of harvesting visible light for more efficient VL-fuel conversion. This methodology affords us to successful access to the novel plasmonic Pt/TiO2-HA (large Pt nanoparticles (NPs) supported on TiO2 hierarchical nano-architecture (TiO2-HA)) photocatalysts that exhibit plasmon absorption in the visible range and consequent outstanding activity and durability for VLWS. Particularly, the Pt/TiO2-HA shows an excellent photocatalytic activity for overall water splitting rather than only for hydrogen evolution (HE), which is superior to those of the conventional plasmonic Au/TiO2 photocatalysts. The synergistic effects of the high Schottky barrier at the Pt–TiO2-HA interface, which induces the stronger reduction ability of hot electrons, and intrinsic Pt catalytic activity are responsible for the exceptional photocatalytic performance of Pt/TiO2-HA and simplify the composition of plasmonic photocatalysts.