Abstract
A carbon-modified TiO2 nanotube (C-TiO2 NT) array is fabricated by depositing carbon in TiO2 NTs, which are prepared by anodization of the Ti sheet. Well-dispersed Pt nanoparticles (NPs) are electrochemically deposited on the C-TiO2 NTs. The performances of the as-prepared NT array electrode in the methanol oxidation reaction (MOR) as an anode are investigated. The results present in this study highlight such a finding: depositing partly graphitized carbon on the inside of TiO2 NTs can significantly enhance the catalytic efficiency. An optimum forward oxidation peak current density (I-pf) of 71.6 mA cm(-2) is obtained from the Pt/C-TiO2 NT anode at a low Pt loading of 23 mu g cm(-2). The achieved I-pf is almost 27 times that achieved on Pt-modified TiO2 NTs without carbon modification. The enhanced catalytic efficiency is mainly attributed to the superior electrical conductivity of the deposited carbon, which facilitates the well dispersion of Pt NPs, charge transfer during the MOR, and removal of the byproduct CO-like species.