Dye-Sensitized Reduced Graphene Oxide Photocatalysts for Highly Efficient Visible-Light-Driven Water Reduction

This article presents a novel dye-sensitized photocatalysis system for photochemical energy conversion by employing reduced graphene oxide (RGO) as a catalyst scaffold and an efficient electron relay mediator between photosensitizer and catalyst. Under visible light irradiation (lambda >= 420 nm), the photocatalyst of Eosin Y sensitized RGO with dispersed Pt nanoparticles exhibits highly efficient activity for hydrogen evolution from water reduction. The highest apparent quantum yield up to 9.3% for hydrogen evolution has been achieved at 520 nm over this photocatalyst. The excellent electron-accepting and electron-transporting properties of RGO greatly facilitate the electrons transfer from excited dye to Pt catalyst, which promotes the photocatalytic activity for hydrogen evolution. This is a first example of RGO participation in visible-light-driven water reduction for H-2 generation in a dye-photosensitized system; a possible mechanism was proposed on the basis of the results of photoelectrochemical and photoluminescence measurements.