Abstract
In addition to being a typical red light emitting center, Eu3+ can also be used to study the evolution of lattice symmetry due to its unique electric dipole leap (5D0-7F2) sensitivity to the lattice environment. Here, we synthesized a series of Ba1-xSrxLa0.9LiWO6: 0.10Eu3+ (x = 0.0–1.0) phosphors and used the leap properties to establish a link between the evolution of the lattice environment and the luminescence properties. The introduction of Sr2+ does not affect the lattice type avoiding the effect of phase transition on the luminescence intensity. The lattice symmetry reaches a minimum at Sr2+ concentration of 0.8, which corresponds exactly to the peak of the luminescence intensity. It demonstrated the feasibility of adjusting the occupancy symmetry of Eu3+ to achieve luminescence enhancement. The covalent effect on the luminescence properties in this system is weak compared to the environmental changes by analyzing the attraction of the cations to O2− in the luminescence center neighbors. At the optimal doping concentration, Ba0.2Sr0.8La0.6LiWO6: 0.40Eu3+ phosphor has excellent internal quantum efficiency 95.3%, good color purity 94.79%, and extremely standard color coordinates (0.667, 0.332). In addition, it still has 80.6% emission intensity at 200°C compared to room temperature, which means it has good thermal stability. The good comprehensive performance has laid an important foundation for its application in WLED.
Published Version
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have