Stepwise cosensitization is carried out on Al2O3-coated nanocrystalline TiO2 layers using two organic dyes (JK-2 and SQ1) having complementary spectral absorption bands in the visible region. The Al2O3 coating results in the retardation of the interfacial charge recombination dynamics at the oxide/sensitizer interface and improves the overall performance of the dye-sensitized solar cells. CB = conduction band.
![Stepwise cosensitization of nanocrystalline TiO2 films utilizing Al2O3 layers in dye-sensitized solar cells](https://www.iciq.org/wp-content/uploads/2014/03/Stepwise-cosensitization_AGE8259.gif)