Pr3+-doped nanoscintillators with concentration-quenching-free properties

Luminescence concentration quenching exists widely in lanthanidedoped luminescent nanomaterials, and significantly hinders their emission intensity. In this work, we report the concentrationquenching-free properties of the 406 nm emission in Pr3+-doped nanoscintillators, which is attributed to the large energy gap between the S-1(0) and I-1(6) states (Delta E = similar to 25000 cm(-1)) of Pr3+ ions, preventing the concentration quenching effects caused by both cross-relaxation and energy migration to surface quenchers. This work provides further understanding about the concentration quenching effect of lanthanide-doped luminescent nanomaterials and a new perspective for avoiding detrimental concentration quenching. In addition, we also demonstrate the potential use of Pr3+-doped nanoscintillators as anti-counterfeiting materials.