Stanford researchers have developed an inexpensive and scalable method to enhance the efficiency of dye-sensitized solar cells (ss-DSCs) by 10-20%. Plasmonic back reflectors which consist of two-dimensional (2D) array of nanotextures were incorporated into the solid-state dye-sensitized solar cells (ss-DSCs). These reflectors enhance absorption through excitation of plasmonic modes and increased light scattering. SS-DSCs with plasmonic back reflectors show increased external quantum efficiency particularly in the long wavelength region of the dye’s absorption band. This process is inexpensive and scalable and allows precise control over the nanotexture size and periodicity. This invention can potentially lead to the development of new commercially viable low cost solar panels. On-going research: 1) Continued research to further improve the overall efficiency of the ss-DSCs 2) Investigating the effect of changing the period of the plasmonic back reflectors on the efficiency improvements 3) Modifying the nanoimprinting lithography process used to pattern the TiO2 nanoparticle film to be done in lower temperature and pressure
1) Increases efficiency of the solar cell by 10-20% 2) Inexpensive and scalable fabrication method - one-step direct imprinting process 3) Allows precise control over the feature size and periodicity Versatile – tested on ss-DSCs but can potentially be applied to any thin-film solar cell materials systems with active layer thickness on the scale of 0.5-10 micron such as amorphous silicon CdTe and Cu(InGa)Se2