Enhanced Photocatalytic H 2 Generation by Light-Induced Carbon Modification of TiO 2 Nanotubes.

Titanium dioxide (TiO 2 ) is the material of choice for photocatalytic and electrochemical applications owing to its outstanding physicochemical properties. However, its wide bandgap and relatively low conductivity limit its practical application. Modifying TiO 2 with carbon species is a promising route to overcome these intrinsic complexities. In this work, we propose a facile method to modify TiO 2 nanotubes (NTs) based on the remnant organic electrolyte retained inside the nanotubes after the anodization process, that is, without removing it by immersion in ethanol. Carbon-modified TiO 2 NTs (C-TiO 2 NTs) showed enhanced H 2 evolution in photocatalysis under UV illumination in aqueous solutions. When the C-TiO 2 NTs were subjected to UV light illumination, the carbon underwent modification, resulting in higher measured photocurrents in the tube layers. After UV illumination, the IPCE of the C-TiO 2 NTs was 4.4-fold higher than that of the carbon-free TiO 2 NTs.