Color-tunable luminescence of Eu3+ in LaF3 embedded nanocomposite for light emitting diode

✍ Scribed by Daqin Chen; Yunlong Yu; Ping Huang; Hang Lin; Zhifa Shan; Yuansheng Wang

• Publisher: Elsevier Science
• Year: 2010
• Tongue: English
• Weight: 959 KB
• Volume: 58
• Category: Article
• ISSN: 1359-6454
• DOI: 10.1016/j.actamat.2010.01.035

✦ Synopsis

Eu 3+ -doped transparent nanocomposite of SiO 2 -Al 2 O 3 -NaF-LaF 3 was fabricated by melt-quenching and subsequent heating. X-ray diffraction and transmission electron microscopy analyses evidenced that hexagonal LaF 3 nanocrystals were homogeneously precipitated among the aluminosilicate glass matrix. The distribution of Eu 3+ ions in the nanocomposite was investigated by energy dispersive X-ray spectroscopy, photoluminescence and time-resolved luminescence spectra. The nanocomposite exhibited intense blue and green emissions originating from the 5 D 1,2,3 levels of Eu 3+ incorporated in the low-phonon-energy LaF 3 nanocrystals, and red emission corresponding to the Eu 3+ : 5 D 0 ? 7 F J (J = 0, 1, 2, 3, 4) transitions, under the excitation of single wavelength light at 394 nm. By adjusting the Eu 3+ doping content, various luminescent colors, including perfect white light, were easily tuned through cross relaxation processes between Eu 3+ ions. The results suggest that the Eu 3+ -doped transparent nanocomposite could be potentially applicable as a white-light-emitting material under UV chip excitation.