Applications of rare earth Tb3+-Yb3+ co-doped down-conversion materials for solar cells

We prepared Tb3+-Yb3+ co-doped silicate glass as a down-conversion layer and used it in solar cells. We confirmed the existence of a down-conversion process in the system by absorption spectroscopy, fluorescence spectroscopy and energy level analysis. Tb3+ ions can absorb high-energy photons and effectively pass the energy to Yb3+ ions. Then Yb3+ ions emit near-infrared photons with energies that match monocrystalline silicon solar cells. As the Yb3+ ion concentration constantly changed, the energy transfer efficiency and the photoelectric conversion efficiency of solar cells both changed. We measured in the standard environment (AM1.5G) and found that Tb3+-Yb3+ co-doped silicate glass samples can improve the photoelectric conversion efficiency of monocrystalline silicon solar cells by 8.6%. Our results show that this material has great potential in the application of solar cells.