Full spectrum enhancement of the light harvesting efficiency of dye sensitized solar cells by including colloidal photonic crystal multilayers

Herein we report a theoretical analysis of the efficiency of dye sensitized solar cells in which colloidal crystals are introduced in different configurations. We find that piling up different lattice constant crystals leads to light harvesting enhancement in the whole dye absorption range. We provide the optimum structural features of such photonic crystal multilayer needed to achieve a photocurrent efficiency enhancement of around 60% with respect to standard dye sensitized solar cells. We demonstrate that this improvement is the result of the optical absorption amplification effect of slow photon resonant modes partially confined within the absorbing part of the cell by the mirror behavior of the colloidal superlattice.