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

University of Alicante, Alicante, Valencia, Spain
Electrochemistry Communications (Impact Factor: 4.85). 10/2006; 8(11):1713-1718. DOI: 10.1016/j.elecom.2006.08.006


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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Available from: Damián Monllor-Satoca
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    • "Nanocrystalline films composed of sintered nanoparticles of TiO2 have interesting properties and have been studied for potential use in photoelectrochemical solar cells, electrochromic windows, and batteries with Li-intercalation [1–7]. The advantages compared with conventional materials are the much larger internal surface accessible due to electrolyte penetration of the porous framework, efficient charge separation, and ion conduction since the transport distance for charge carriers to travel becomes short in the nanocrystallites [8, 9]. "
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