Excellent red phosphors of double perovskite Ca{sub 2}LaMO{sub 6}:Eu (M=Sb, Nb, Ta) with distorted coordination environment

Journal Article · Thu Dec 15 00:00:00 EST 2011 · Journal of Solid State Chemistry

DOI:https://doi.org/10.1016/j.jssc.2011.10.032· OSTI ID:21612835

Xin, Yin; Yaoming, Wang ^[1]; Yujuan, Xia; Dongyun, Wan ^[1]

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1. State Key Laboratory of High Performance Ceramics and Superfine Microstructures and CAS Key Laboratory of Materials for Energy Conversion, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai 200050 (China)

Double perovskite Ca{sub 2}LaSbO{sub 6}, successfully synthesized by solid state reaction method, was identified by Rietveld refinements to crystallize in the monoclinic space group P2{sub 1}/n, which is isostructural to Ca{sub 2}LaMO{sub 6} (M=Nb, Ta). Excellent red luminescence of Eu-doped Ca{sub 2}LaMO{sub 6} (M=Sb, Nb, Ta) can be obtained and no luminescence quenching effect was observed when Eu-doping level reached 40%. For Ca{sub 2}La{sub 0.6}NbO{sub 6}:0.4Eu{sup 3+}, quantum efficiencies of 20.9% and 27.7% were reached to show high light conversion and bright red emission excited at 465 nm (blue light) and 534 nm (green light), respectively, comparable to the commercial phosphors. Through systemic investigation for the series of double perovskite compounds, the excellent red emission in Ca{sub 2}LaMO{sub 6} is attributed to highly distorted polyhedra of EuO{sub 8} (low tolerance factor of the pervoskite), and large bond distances of La-O (low crystal field effect of the activator). - Graphical Abstract: Eu{sup 3+} doped double-perovskite compounds A{sub 2}LnMO{sub 6} (A=Ca, Sr, Ba; Ln=La, Gd, Y; M=Sb, Nb, Ta) show the dependence of luminescence intensity on the crystal structure. Highlights: Black-Right-Pointing-Pointer A series of double perovskite compounds were synthesized by solid state reaction. Black-Right-Pointing-Pointer Eu{sup 3+} doped samples display intense red emission when excited by blue or green light. Black-Right-Pointing-Pointer High quantum efficiency was obtained, comparable to the commercial phosphors. Black-Right-Pointing-Pointer Luminescence properties were ascribed to crystal distortion and large Ln-O distance.

• OSTI ID: 21612835
• Journal Information: Journal of Solid State Chemistry, Vol. 184, Issue 12; Other Information: DOI: 10.1016/j.jssc.2011.10.032; PII: S0022-4596(11)00574-3; Copyright (c) 2011 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved.; Country of input: International Atomic Energy Agency (IAEA); ISSN 0022-4596
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC
ORGANIC
PHYSICAL AND ANALYTICAL CHEMISTRY
CRYSTAL FIELD
CRYSTALS
DOPED MATERIALS
EUROPIUM IONS
LUMINESCENCE
MONOCLINIC LATTICES
PEROVSKITE
PHOSPHORS
QUANTUM EFFICIENCY
SOLIDS
SPACE GROUPS
CHARGED PARTICLES
CRYSTAL LATTICES
CRYSTAL STRUCTURE
EFFICIENCY
EMISSION
IONS
MATERIALS
MINERALS
OXIDE MINERALS
PEROVSKITES
PHOTON EMISSION
SYMMETRY GROUPS