Tin Oxide Light-Scattering Layer for Titania Photoanodes in Dye-Sensitized Solar Cells

High-performance dye-sensitized solar cell (DSSC) devices rely on photoanodes that possess excellent light-harvesting capabilities and high surface areas for sufficient dye adsorption. In this work, morphologically controlled SnO2 microstructures were synthesized and used as an efficient light-backscattering layer on top of a nanocrystalline TiO2 layer to prepare a double-layered photoanode. By optimizing the thickness of both the TiO2 bottom layer and the SnO2 top layer, a high power conversion efficiency (PCE) of 7.8% was achieved, an enhancement of approximately 38% in the efficiency compared with that of a nanocrystalline TiO2-only photoanode (5.6%). We attribute this efficiency improvement to the superior light-backscattering capability of the SnO2 microstructures.