High efficient near-infrared quantum cutting in Ce3+,Yb3+ co-doped LuBO3 phosphors

High efficient near-infrared (NIR) quantum cutting (QC) LuBO3:Ce3+,Yb3+ phosphors had been synthesized by hydrothermal method with further heat treatment. Due to the cooperative energy transfer (CET) from one Ce3+ to two Yb3+ ions, an intense NIR emission around 971 nm of Yb3+: 2F5/2 → 2F7/2 transition was obtained under 369 nm excitation. Yb3+ concentration dependent quantum efficiency has been calculated and the maximum efficiency approaches up to 181% before reaching the critical concentration quenching threshold. Because the 971 nm emission of Yb3+ is matched with the band gap of crystalline Si, the phosphors may be applied potentially in silicon-based solar cells.