Abstract
? 2022 Elsevier B.V.The crystal structure, photoluminescence properties, thermal stability and corresponding mechanisms of the novel Bi3+, Eu3+-doped La2SrSc2O7 (LSS) phosphors have been measured and analyzed in details. The emission spectrum of LSS: 1.0%Bi3+ phosphor shows a novel green emission centered at 530 nm under 340 nm excitation, which is attributed to the 3P1→1S0 transition of Bi3+ ions. By designing Bi3+→Eu3+energy transfer strategy, luminescence colors of LSS: 1.0%Bi3+, yEu3+ (y = 0–5.0%) phosphors can be tuned from green to orange with increasing Eu3+ concentration, which achieve multiple emission colors in LSS host. The photoluminescence decay curves, average decay lifetimes, energy transfer efficiency and time-resolved emission spectra of LSS: 1.0%Bi3+, yEu3+ (y = 0–5.0%) phosphors prove the existence of energy transfer from Bi3+ to Eu3+. The prototype pc-WLED device with green-emitting LSS: 1.0%Bi3+ possesses high color rendering index (CRI = 96.0) and low correlated color temperature (CCT = 4306 K). These results provide clear evidences that LSS: Bi3+and LSS: 1.0%Bi3+, Eu3+ phosphors would be novel promising green-to-orange tunable phosphor candidates for pc-WLED applications.
NSTL
Elsevier