Enhancing photovoltaic performance of dye-sensitized solar cells by rare-earth doped oxide of SrAl2O4:Eu3+

• A down-conversion (DC) nanocrystal (SrAl2O4:Eu3+) was synthesized.
• The effect of SrAl2O4:Eu3+ doped in photoanode in DSSCs was investigated.
• SrAl2O4:Eu3+ doped in photoanode appeared the better photovoltaic performances.
• The dual function of DC and p-type doping effect were explained.

SrAl2O4:Eu3+ down-conversion (DC) nanocrystals were synthesized by a sol–gel method and then doped in TiO2 as a photoanode in dye-sensitized solar cells (DSSCs). Differential thermal analysis, fourier transform infrared spectroscopy, X-ray diffraction and Brunauer–Emmet–Teller analysis confirmed the formation of SrAl2O4:Eu3+ nanocrystals with diameters of ∼47 nm, pore size of ∼25 nm, sintering temperature of 1300 °C. The photoluminescence and UV–vis absorption spectra of the SrAl2O4:Eu3+ revealed a DC from ultraviolet light to visible light which matched the strong absorbing region of the N719 dye. The photoelectric conversion efficiency of the DSSCs with a TiO2 photoanode doped with 3 wt% SrAl2O4:Eu3+ was 20% higher than that with a pure TiO2 photoanode. This phenomenon could be mainly explained by SrAl2O4:Eu3+ nanocrystals’ ability of DC and increased the short-circuit current density. It could be minorly due to the p-type doping effect and slightly improved the open-circuit voltage.

Current–voltage characteristics of DSSCs based on the photoanodes doping different SrAl2O4:Eu3+ and doping 3% SrAl2O4.Figure optionsDownload as PowerPoint slide