Organic dye-sensitized sponge-like TiO₂ photoanode for dye-sensitized solar cells.

Light harvesting inside a solar cell is crucial for overall performance. Increasing the optical path of a photon through the delicate design of photoanode morphology can increase the light absorbance. The marine sponge-like photoanode is facilely constructed and assembled into a solar cell, using an organic D-A-π-A-type dye with wide-spectrum response as the sensitizer. The light scattering derived from the large porous cavities in the photoanode enhances the improved light absorbance of the dye molecules, especially in the long-wavelength region, and therefore improves the cell efficiency. Synergistically engineering the photoanode morphology and adopting matchable dye maximized the light energy conversion efficiency in this study, and a maximal conversion efficiency of 5.02% was achieved.