Enhanced optical absorption of dye-sensitized solar cells with microcavity-embedded TiO2 photoanodes

This paper reports the enhanced performance of dye-sensitized solar cells (DSSCs) with microcavity-embedded nanoporous TiO2 photoanodes. For DSSCs with photoanodes composed of a stack TiO2 sublayers with microcavity concentrations arranged from low to high on the light illumination path, the short-circuit current density and the conversion efficiency were improved. A pronounced increase in optical absorption and incident monochromatic photon-to-current conversion efficiency in the long-wavelength region indicated that the enhancement of cell performance was due to the multiple scattering of light by the microcavities and the light confinement by the stack of TiO2 sublayers with a high-to-low effective index of refraction.