Carbon doped TiO2 nanowire arrays with improved photoelectrochemical water splitting performance

In the present study, we demonstrate a facile route to fabricate vertical-aligned carbon doped TiO2 nanowire arrays on FTO substrate by combining of a simple hydrothermal growth and a subsequent calcination process in air. The photoelectrochemical measurements indicate that the carbon doped TiO2 photoanode yields a ∼70% enhancement in the photocurrent density in comparison to that of the pristine TiO2. Further IPCE, diffuse reflectance spectra and electrochemical impedance characterizations confirm that the photocurrent improvement is mainly in the UV light region, which is arise from the increased charge carrier densities as well as improved charge transfer and separation induced by carbon doping.

Highlights► Carbon doped TiO2 nanowire arrays were fabricated by a combined hydrothermal and subsequent calcination process. ► Carbon doping enhanced the photoelectrochemical water splitting performance. ► The enhanced performances were mainly arise from improved charge transportation and separation.