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Charge transfer reductive doping of nanostructured TiO 2 thin films as a way to improve their photoelectrocatalytic performance

Electrochemistry Communications (Impact Factor: 4.43). 10/2006; 8:1713-1718. DOI: 10.1016/j.elecom.2006.08.006

ABSTRACT Nanostructured TiO 2 films can be reversibly doped by applying a potential of À0.6 V Ag/AgCl in aqueous 0.1 M HClO 4 for several min-utes. This charge transfer reductive doping causes significant changes of the cyclic voltammograms in the dark. Furthermore, an up to 6-fold increase of the efficiency for water photooxidation is observed upon electrochemical reductive doping. Both observations are explained by the build-up of a space charge layer through agglomerates of appropriately sized and shaped nanoparticles.

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May 26, 2014