Modification of Mesoporous TiO2 Films by Electrochemical Doping: Impact on Water Photooxidation and Photoconversion Efficiency in Dye-sensitized Solar Cells
Juan Antonio Anta a, Jesús Idígoras a, Thomas Berger a
a Pablo de Olavide University, Sevilla, Spain, Carretera de Utrera, km. 1, Montequinto, Spain
Poster, Thomas Berger, 028
Publication date: 31st March 2013

A simple electrochemical treatment, the cathodic polarization in aqueous electrolyte, known as reductive electrochemical doping, constitutes an appropriate tool to modify to some extent the properties of nanocrystalline TiO2 electrodes (1-4). In this contribution, the effect of electrochemical doping on the photoelectrocatalytic and photovoltaic properties of TiO2 films based on commercial powders will be discussed. The degree and the persistence of thin film modification upon electrochemical doping in aqueous solution was found to depend on thin film morphology and was tracked in situ by the detection of IR-active trapped electrons. The doping treatment alters the macroscopic behavior of the TiO2 electrodes concretely it increases both the photoelectrocatalytic activity with respect to water oxidation and the photoconversion efficiency of dye-sensitized solar cells (DSCs) based on the modified electrodes. The effect has been analyzed using small-perturbation electrochemical techniques (impedance spectroscopy, intensity-modulated photovoltage and photocurrent spectroscopy). The results indicate that the better photoelectrocatalytic and photovoltaic efficiency is due to a more rapid electron transport combined with reduced recombination, contributing to improved electron collection. Furthermore, an enhancement in electron injection is also inferred from the analysis of the presented results (5).


Impact of Electrochemical Doping on Water Photooxidation and Photoconversion Efficiency in Dye-sensitized Solar Cells
(1) Meekins, B. H.; Kamat, P. V. Got TiO2 Nanotubes? Lithium Ion Intercalation Can Boost Their Photoelectrochemical Performance ACS Nano 2009, 3, 3437−3446. (2) Fabregat-Santiago, F.; Barea, E. M.; Bisquert, J.; Mor, G. K.; Shankar, K.; Grimes, C. A. High Carrier Density and Capacitance in TiO2 Nanotube Arrays Induced by Electrochemical Doping J. Am. Chem. Soc. 2008, 130, 11312−11316. (3) Wang, Q.; Zhang, Z.; Zakeeruddin, S. M.; Grätzel, M. Enhancement of the Performance of Dye-Sensitized Solar Cell by Formation of Shallow Transport Levels under Visible Light Illumination J. Phys. Chem. C 2008, 112, 7084−7092. (4) Berger, T.; Lana-Villarreal, T.; Monllor-Satoca, D.; Gómez, R. Charge Transfer Reductive Doping of Nanostructured TiO2 Thin Films as a Way to Improve Their Photoelectrocatalytic Performance Electrochem. Commun. 2006, 8, 1713−1718. (5) Idígoras, J.; Berger, T.; Anta, J. A. Modification of Mesoporous TiO2 Films by Electrochemical Doping: Impact on Photoelectrocatalytic and Photovoltaic Performance J. Phys. Chem. C 2013, 117, 1561−1570.
© Fundació Scito
We use our own and third party cookies for analysing and measuring usage of our website to improve our services. If you continue browsing, we consider accepting its use. You can check our Cookies Policy in which you will also find how to configure your web browser for the use of cookies. More info