Dye-sensitized solid-state solar cells made from magnesiumoxide-coated nanocrystalline titanium dioxide films: enhancement of the efficiency

Dye-sensitized solid-state solar cells have low energy and quantum-conversion efficiencies because of the high recombination rate at the n-type semiconductor/dye/p-type semiconductor interfaces. It is found that the efficiency of dye-sensitized solid-state solar cells with nanocrystalline TiO2 as the n-type material and CuI as the p-type material can be greatly enhanced by the deposition of an ultrathin layer of MgO on the TiO2 crystallites. Mechanism involved is explained.