Enhanced luminescence and tunable color in [Eu2+, Si4+]/Mn2+ doped K2BaCa(PO4)2 based on charge compensation and energy transfer. Issue 23 (24th May 2021) - Wang, Peng
Abstract : After designing an [Eu 2+, Si 4+ ] → [K +, P 5+ ] charge compensation strategy, the luminescence tuning performance of K2 BaCa(PO4 )2 :[Eu 2+, Si 4+ ], Mn 2+, which originated from energy transfer, was studied in detail. Abstract : Recently, using the Eu 2+ → Mn 2+ energy transfer strategy to explore new single-phase phosphors suitable for the near-ultraviolet (n-UV) region has become one of the major strategies in solid-state lighting applications. Therefore, a novel color-tunable K2 BaCa(PO4 )2 (KBCPO):[Eu 2+, Si 4+ ], Mn 2+ phosphor was developed because of the preeminent thermal stability of luminescence of Eu 2+ -activated KBCPO. In this study, we first designed a [Eu 2+, Si 4+ ] → [K +, P 5+ ] charge compensation strategy to optimize the luminescence properties of Eu 2+ in the KBCPO matrix. In terms of the obtained KBCPO:[Eu 2+, Si 4+ ] phosphor, this charge compensation method on the one hand strengthens the emission of Eu 2+, and on the other hand, it dramatically improves the thermal stability of luminescence. In particular, the emission intensity of the KBCPO:0.03[Eu 2+, Si 4+ ] sample at 548 K can reach 103% relative to that at the initial temperature of 298 K. Based on this charge compensation strategy, we finally obtained a new dual emission KBCPO:[Eu 2+, Si 4+ ], Mn 2+ phosphor. The analysis of the luminescence properties indicates that the emission enhancement of Mn 2+ in KBCPO:[Eu 2+, Si 4+ ], Mn 2+ stems from the energy transfer of Eu 2+ → Mn 2+ with the mechanism of the electric dipole–dipole interaction when excited at 365 nm. In addition, KBCPO:[Eu 2+, Si 4+ ], Mn 2+ also has excellent thermal stability and the emission color could be easily tuned from cyan to orange only by adjusting the Eu 2+ doping level. These results confirm that the KBCPO:[Eu 2+, Si 4+ ], Mn 2+ phosphor is a viable candidate for n-UV white light emitting diodes.