Effect of annealing temperatures on luminescence properties in Ce3+-Yb3+ codoped oxyfluoride glass-ceramics for solar cells

An efficient near-infrared (NIR) down-conversion in Ce3+-Yb3+ codoped oxyfluoride glass ceramics (GC) have been investigated with different annealing temperature. With an 430 nm (Ce3+: 4f → 5d) excitation, the NIR emission at around 1000 nm (Yb3+: 2F5/2 → 2F7/2) was obtained which confirming efficient energy transfer between Ce3+ ions and Yb3+ ions. Subsequently, the possible mechanism of energy transfer was investigated and discussed. Finally, the energy conversion efficiency was measured which the Si solar cell covered by Ce3+-Yb3+ codoped oxyfluoride GC. The maximum efficiency which increased by 0.3% indicated that the Ce3+/Yb3+ sample had the potential applications for solar cells.