Choice of low thermal quenching phosphors based on high lattice energy for light-emitting application

Abstract

High efficient white light-emitting diodes, near-ultraviolet chips with trichromatic phosphors, have been widely studied in recent years. Herein, we report novel blue-/red-emitting Bi3+/Eu3+ doped Ca3Sc2Si3O12 (CSSO) phosphors with superior thermal stability. Comparing to traditional fluorescent materials Y3Al5O12 (YAG) and Y2O3, photoluminescence (PL) emission intensities of Bi3+ or Eu3+ doped CSSO phosphors maintain 92.4% and 98.6% of initial intensity at 300 K when measured at 423 K. More importantly, it is found that the lattice energy (Ucal) of host can determine thermal quenching behavior of phosphors. By chemical bond theory for complex crystals, the Ucalof CSSO, YAG and Y2O3 are calculated to be 143,060, 58,331 and 12,484 kJ/mol, indicating that CSSO with weak thermal quenching property is due to high Ucal. Subsequently, superior thermal stability of CSSO phosphors is further certified by fingerprints identification and anti-counterfeiting ink at high temperature. This work clearly exhibits a new and convenient strategy to predict the luminescent phosphors with good thermal stability before doing experiments.