Graphitic domain layered TiO2 nanotube for separation and transportation of photoexcited electrons

Abstract

We report a facile method for fabricating a novel structure of graphitic domains on the surface of titania nanotubes, prepared by using hydrothermal and pyrolytic treatments with glucose. The two to four sp2-bonded carbon layers (less than 1 nm) with thin island shape are created along the surface curvature of TiO2 nanotubes. The fast decay time for photoexcited electrons (separation) and the low charge transport resistance (transportation) prove that the number of solar-driven electrons which can participate to reaction of proton reduction is increase by the layered graphitic domains, which result in an increase in solar-to-hydrogen conversion rate. Therefore, we expect that our facile method for combine graphitic domains with a broad class of semiconductors could provide an innovative means for suppressing charge recombination and promoting the materials' photocatalytic properties.