Preparation of long persistent phosphor SrAl2O4:Eu2+, Dy3+ and its application in dye-sensitized solar cells

SrAl2O4:Eu2+, Dy3+ powder has been successfully prepared via a combustion method and then introduced into the titanium dioxide (TiO2) film photoanode of the dye-sensitized solar cell (DSSC). The influence of the amount of doping on the light-to-electric energy conversion efficiency was discussed. At the concentration 7 wt% of SrAl2O4:Eu2+, Dy3+ (weight ratio of phosphor powder to TiO2), an overall 20 % improvement was achieved compared to that of the DSSC without SrAl2O4:Eu2+, Dy3+ phosphor doping. The enhancement is mainly due to the presence of the long persistent phosphor doping. It can convert ultraviolet to visible luminescence via down-conversion luminescence. Owing to the emission of long persistent light, the DSSC with SrAl2O4:Eu2+, Dy3+ showed an efficiency of 0.0076 % in the dark after illuminated under a simulated solar light for 1 min. This method represents a novel approach to increase the efficiency of DSSC.