Hollow SnO2 microspheres for high-efficiency bilayered dye sensitized solar cell

We synthesized hollow SnO2 microspheres using a hydrothermal method and fabricated bilayered dye sensitized solar cells (DSSCs) with hollow SnO2 microspheres as the top layer and TiO2 as the bottom layer. Due to the reduced transfer resistance, faster diffusion constants, and enhanced light harvesting, the performance of the bilayered DSSC with SnO2 top layer was better than that without SnO2 top layer. A maximum power conversion efficiency (PCE) of 4.15% was obtained for this bilayered DSSC under illumination of one sun (AM 1.5 G, 100 mW cm(-2)), which exhibited a 19% improvement compared to the QDSSC without a SnO2 layer.