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 capability and high surface area for sufficient dye adsorption. In this work, morphologically controlled SnO2 microstructures have been synthesized and used as an efficient light backscattering layer on top of the nanocrystalline TiO2 layer to prepare a double-layered photoanode. By optimizing the thickness of both the TiO2 bottom layer and SnO2 top layer, a high power conversion efficiency (PCE) of 7.8% is achieved, demonstrating a ~38% enhancement in the efficiency when compared to a nanocrystalline TiO2-only photoanode (5.6%). We attribute this efficiency improvement to the superior light backscattering capability of SnO2 microstructures.