Application of Yb3+, Er3+-doped yttrium oxyfluoride nanocrystals in dye-sensitized solar cells

Yb3+, Er3+-doped yttrium oxyfluoride [YOF:(Yb3+, Er3+)], acting as a luminescence medium, is introduced into the TiO2 electrode. Owing to the effect of up-conversion, it increases the photocurrent and efficiency of the DSSC. Besides, as a p-type dopant, YOF:(Yb3+, Er3+) enhances the Fermi level of TiO2 film and the photovoltage of the DSSC. When the doping amount of YOF:(Yb3+, Er3+) is 7 wt.%, the light-to-electric energy conversion efficiency of the DSSC reaches 7.217%, increasing by a factor of 1.23 compared to that of a DSSC without YOF:(Yb3+, Er3+)dopant. (C) 2012 Elsevier Ltd. All rights reserved.