Crystal structures and luminescence properties of Eu²⁺-activated new NaBa0.5Ca0.5PO₄ and Na₃Ba₂Ca(PO₄)₃
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Updated: Apr 19, 2026
Low-energy Cathodoluminescence for OxyNitride Phosphors
Published on: November 15, 2016
Minsung Kim1, Makoto Kobayashi, Hideki Kato
1Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, Sendai 980-8577, Japan. kakihana@tagen.tohoku.ac.jp.
Abstract:
NaBa(1-x)Ca(x)PO4:Eu(2+) were synthesized using polymerizable complex method. New phases were observed at x = 1/3 and 0.5, which were identified by single-crystal XRD analysis as Na3Ba2Ca(PO4)3 and NaBa0.5Ca0.5PO4 with a trigonal system. Though both phases pretend to be solid solutions between NaBaPO4 and NaCaPO4, they have different coordination environments and PO4 orderings. 1 mol% Eu(2+)-activated NaBaPO4, Na3Ba2Ca(PO4)3, and NaBa0.5Ca0.5PO4 exhibited an emission maximum at 435 nm, 458 nm, and 460 nm, respectively. The shift of the emission maximum might be due to a change in the Eu-O bond length.
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