Extra-Broad Band Orange-Emitting Ce 3+ -Doped Y 3 Si 5 N 9 O Phosphor for Solid-State Lighting: Electronic, Crystal Structures and Luminescence Properties
2016; American Chemical Society; Volume: 28; Issue: 13 Linguagem: Inglês
10.1021/acs.chemmater.6b02109
ISSN1520-5002
AutoresQiangqiang Zhu, Le Wang, Naoto Hirosaki, Lü Hao, Xin Xu, Rong‐Jun Xie,
Tópico(s)Inorganic Chemistry and Materials
ResumoLuminescent materials play an important role in making solid state white light-emitting diodes (w-LEDs) more affordable home lighting applications. To realize the next generation of solid-state w-LEDs with high color-rendering index (CRI), the discovery of broad band and long emission wavelength luminescent materials is an urgent mission. Regarding this, the oxonitridosilicate Y3Si5N9O with a high nitrogen concentration should be a suitable host material to achieve those promising luminescent properties. In this work, a phase-pure Ce3+-doped Y3Si5N9O was successfully synthesized through the carbothermal reduction and nitridation method. Y3Si5N9O:Ce3+ shows an emission maximum at 620 nm and an extremely broad emission band with a full-width at half-maximum (fwhm) of 178 nm. The electronic and crystal structure calculations indicate an indirect band gap of 2.6 eV (experimental value: 4.0 eV), and identify two Ce3+ sites with different local environments that determine the luminescence properties. The orange-emitting phosphor has the absorption, internal and external quantum efficiencies of 89.5, 17.2, and 15.6% under 450 nm excitation, respectively. The valence state of Ce, cathodoluminescence, decay time, and thermal quenching of the phosphor were also investigated to understand the structure–property relationships.
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