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Updated: Dec 7, 2025

Low-energy Cathodoluminescence for OxyNitride Phosphors
Published on: November 15, 2016
Ultrahigh-Energy-Transfer Efficiency and Efficient Mn2+ Red Emission Realized by Structural Confinement in
Xinguo Zhang1,2, Jiabao Luo1, Zishan Sun1
1Guangdong Provincial Key Laboratory of New Drug Screening, School of Pharmaceutical Sciences, Southern Medical University, Guangzhou 510515, China.
Abstract:
Structural confinement on Eu2+-Mn2+ optical centers is an effective strategy to boost Mn2+ red emission. On the basis of the Ca9LiMn(PO4)7 (CLMP) host with a compact Eu2+-Mn2+ distance of ∼3.5 Å, a pure and intense Mn2+ red emission without seeing Eu2+ emission is realized, indicating that an ultrahigh energy transfer (ET) could be induced by a structural confinement effect. It is found that the Mn2+ emission intensity and quantum efficiency could be further improved by a Tb3+ bridging effect, which offers extra energy levels to reduce the energetic mismatch between the excited states of Eu2+ and Mn2+. The optimal sample CLMP:0.02Eu2+,0.90Tb3+ shows a promising performance in terms of high color purity (93.9%), high quantum efficiency (QE = 51.2%), and good thermal stability (70% of the room-temperature value at 373 K). All of the results demonstrate that CLMP:Eu2+,Tb3+ phosphor is a promising red-light-emitting-diode phosphor, and the structural confinement effect should be developed as a general strategy to enhance the ET efficiency for a pure and efficient emission.
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