ORCID: https://orcid.org/0000-0003-4571-8035
(2018):
Orange-Emitting Li4Sr4[Si4O4N6]O:Eu2+-a Layered Lithium Oxonitridosilicate Oxide.
In: Inorganic Chemistry, Vol. 57, No. 22: pp. 14304-14313
Abstract
We report on the structure and properties of the lithium oxonitridosilicate oxide Li4Sr4[Si4O4N6]O:Eu2+ obtained from solid-state metathesis. The crystal structure was solved and refined from single-crystal Xray data in the space group P4(2)/nmc (No. 137) [Z = 2, a = 7.4833(6), c = 9.8365(9) angstrom, and R1(obs) = 0.0477]. The structure of Li4Sr4[Si4O4N6]O:Eu2+ is built up from a layered 2D network of SiN3O tetrahedra and exhibits stacking disorder. The results are supported by transmission electron microscopy and energy-dispersive X-ray spectroscopy as well as lattice energy, charge distribution, and density functional theory (DFT) calculations. Optical measurements suggest an indirect band gap of about 3.6 eV, while DFT calculations on a model free of stacking faults yield a theoretical electronic band gap of 4.4 eV. Samples doped with Eu2+ exhibit luminescence in the orange spectral range (lambda(em) approximate to 625 nm;full width at half-maximum approximate to 4164 cm(-1);internal quantum efficiency at room temperature = 24%), extending the broad field of phosphor materials research toward the sparsely investigated materials class of lithium oxonitridosilicate oxides.
Item Type: | Journal article |
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Faculties: | Chemistry and Pharmacy > Department of Chemistry |
Subjects: | 500 Science > 540 Chemistry |
ISSN: | 0020-1669 |
Language: | English |
Item ID: | 67433 |
Date Deposited: | 19. Jul 2019, 12:22 |
Last Modified: | 04. Nov 2020, 13:49 |