Effect of Cathodic Polarization of n-TiO2 Thin Films on Their Photoresponse towards Water Splitting Reactions

Cathodic reduction of Titanium oxide (n-TiO2) thin films was investigated as an alternative approach to customary hydrogen modification of n-TiO2 under hydrogen gas stream at high temperature. Hydrogen modification of n-TiO2 was carried out electrochemically under cathodic polarization. The photo-response of the electrochemically hydrogen modified n-TiO2 (HM-n-TiO2) exhibited a fourfold enhancement in their photoresponse compared to n-TiO2 during water splitting under solar simulated light. The photoactivity of HM-n-TiO2 suffers a substantial decrease after heat-treatment at 200 degrees C, remarkably the photoactivity of these samples was fully repaired after re-hydrogenation under similar conditions. The electrodes were characterized using electrochemical and spectroscopic techniques. (C) The Author(s) 2014. Published by ECS. This is an open access article distributed under the terms of the Creative Commons Attribution 4.0 License (CC BY, http://creativecommons.org/licenses/by/4.0/), which permits unrestricted reuse of the work in any medium, provided the original work is properly cited. All rights reserved.