Using energy relay dyes to increase light absorption in dye-sensitized solar cells

摘要

Improved efficiency for dye-sensitized solar cells is provided using a combination of dyes that have distinct roles—a sensitizing dye and an energy relay dye. The sensitizing dye is disposed on the surface of a photo-electrode, and is capable of absorbing incident radiation and of transferring charge at the photo-electrode surface. The energy relay dye is disposed in the electrolyte of the solar cell. The energy relay dye is capable of absorbing incident radiation and is capable of non-radiative energy transfer to the sensitizing dye. The energy relay dye need not be capable of direct charge transfer at the photo-electrode surface. We have found that the presence of such an energy relay dye can significantly increase solar cell efficiency compared to conventional dye-sensitized solar cell approaches having the dye (or dyes) all adsorbed to the photo-electrode surface. In an experiment, a 26% increase in power conversion efficiency was obtained when using an energy relay dye (PTCDI) with an organic sensitizing dye (TT1).