Concentration-dependent near-infrared quantum cutting in NaYF4:Pr3+, Yb3+ phosphor

Near-infrared quantum cutting phenomenon has been demonstrated in Pr3+–Yb3+-codoped NaYF4 microcrystals synthesized by a facile hydrothermal route, which involves the emission of two near-infrared photons from an absorbed blue photon via a cooperative downconversion process. The Pr3+–Yb3+ energy transfer mechanisms have been identified by the dependence of Yb3+ doping concentration on the visible and infrared emissions, decay lifetime, and quantum efficiency. Upon excitation of Pr3+ ions with a blue photon at 443 nm, Yb3+ ions emit two near-infrared photons at 977 nm with an optimal quantum efficiency of 133.6%. The excellent luminescence properties of NaYF4:Pr3+, Yb3+ microcrystal demonstrate its potentiality to become identified as a better candidate for application as downconversion layer on the top of crystalline silicon solar cell panels in order to reduce thermalization loss.