Near-infrared quantum cutting in Ce3+, Yb3+ co-doped YBO3 phosphors by cooperative energy transfer

An efficient near-infrared (NIR) quantum cutting (QC) in Ce3+, Yb3+ co-doped YBO3 phosphors has been demonstrated, which involves the emission of two low-energy NIR photons (around 973 nm) from an absorbed ultra-violet (UV) photon at 358 nm via a cooperative energy transfer (CET) from Ce3+ to Yb3+ ions. Yb3+ concentration dependent quantum efficiency has been calculated and the maximum efficiency approaches up to 175% before reaching the critical concentration quenching threshold. The development of NIR QC Ce3+, Yb3+ co-doped phosphors may open up a new approach to achieve high efficiency silicon-based solar cells by means of downconversion.