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

Highlights: • Tb³⁺-Yb³⁺ co-doped glass was prepared as a down-conversion layer for solar cells. • The efficiency of solar cell with down-conversion layer increased by up to 8.6%. • Our results show that this down-conversion material has great potential in solar cells. -- Abstract: 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.