Inhomogenous Broadening, Charge Compensation, and Luminescence Quenching in Ce 3+ -Doped Sr 3 AlO 4 F Phosphors

Abstract

© The Author(s) 2015. Published by ECS. The local coordination around luminescent ions in phosphors can affect the properties of these materials. In this report, we analyze the Ce3+ luminescence for the various Ce3+ centers in Sr3AlO4F-based phosphors and use the excitation, emission, and quenching of these phosphors to infer aspects of the local coordination. It is shown that Ce3+ centers with lower energy 4f1→5d1 absorption bands are likely from charge compensation effects by the replacement of F- by O2-. In addition, at higher RE3+ concentrations, additional Ce3+ centers with even lower energy 4f1→5d1 absorption bands are present, presumably due to Ce3+-RE3+ pair formation and O2- charge compensation. These Ce3+ centers with lower energy 4f1→5d1 absorption bands have their luminescence strongly quenched at room temperature. The relationships between composition and Ce3+ luminescence quenching for Sr3AlO4F-based phosphors are also discussed, giving evidence that Ce3+(5d1) ionization is the main cause for luminescence quenching in these materials.