Zn-doped TiO2 electrodes in dye-sensitized solar cells for enhanced photocurrent

Abstract

Porous nanocrystalline Zn/TiO2 materials were synthesized employing agarose gel as a template, achieving a maximum Zn-doping concentration of around 2 at.%. Low Zn-doping concentrations (e.g. <1 at.%) improved the photocurrent of the dye-sensitized solar cell when these materials were applied as the working electrode, as n-type doping favors electron transportation. Compared to the efficiency of the undoped sample, 6.7%, the 0.5 at.% sample showed a much higher efficiency of 7.6%. Further doping decreases the performance of the device as it introduces deficiencies that act as electron–hole recombination centers. © 2012 The Royal Society of Chemistry