Enhanced photovoltaic performance of dye-sensitized solar cells based on NaYF4:Yb(3+), Er(3+)-incorporated nanocrystalline TiO2 electrodes

J Colloid Interface Sci. 2015 Aug 1:451:15-20. doi: 10.1016/j.jcis.2015.03.053. Epub 2015 Apr 3.

Abstract

Near infrared to visible up-conversion of light by rare earth ion-doped phosphors (NaYF4:Yb(3+), Er(3+)) that convert multiple photons of lower energy to higher energy photons offer new possibilities for improved performance of photovoltaic devices. Here, up-conversion phosphor NaYF4:Yb(3+), Er(3+) doped nanocrystalline TiO2 films are designed and used as a electrode for dye-sensitized solar cells, and the photovoltaic performance of DSSCs based on composite electrodes are investigated. The results show the cell with NaYF4:Yb(3+), Er(3+) achieves a power conversion efficiency of 7.65% under one sun illumination (AM 1.5G, 100mWcm(-2)), which is an increase of 14% compared to the cell without NaYF4:Yb(3+), Er(3+) (6.71%). The performance improvement is attributed to the dual effects of enhanced light harvesting from extended light absorption range and increased light scattering, and lower electron transfer resistance.

Keywords: Dye sensitized solar cell; Light harvesting; Light scattering; NaYF(4):Yb(3+), Er(3+).