Crystal growth of Ca3SiO4Br2: New photoluminescence bromosilicate host

✍ Scribed by Zhiguo Xia; Qiang Li; Guowu Li; Ming Xiong; Libing Liao

• Publisher: Elsevier Science
• Year: 2011
• Tongue: English
• Weight: 651 KB
• Volume: 318
• Category: Article
• ISSN: 0022-0248
• DOI: 10.1016/j.jcrysgro.2010.10.058

✦ Synopsis

Single crystals of new bromosilicate compound Ca 3 SiO 4 Br 2 were grown out of high-temperature Ca 2 SiO 4 / CaBr 2 melts by the slow cooling process. Colorless, transparent and flaky crystals of Ca 3 SiO 4 Br 2 were directly isolated from the final solid coagulation. The as-obtained crystals were investigated by energy dispersive X-ray spectrometer (EDS), scanning electron microscope (SEM) and polarized light microscope (PLM). The structure of the new Ca 3 SiO 4 Br 2 compound was determined by single-crystal X-ray diffraction, and it crystallized in the triclinic system, space group P-1 with unit cell parameters a¼ 8.0051(18) Å, b ¼ 8.720(3) Å, c ¼ 11.749(3) Å, a¼69.07(0)1, b¼89.98(0)1, g¼75.46(0)1 and V¼ 737.88(196) Å3 , Z ¼3.

Interestingly, a significant amount of Eu 2 + enters the Ca 3 SiO 4 Br 2 phase, and the Eu 2 + -doped Ca 3 SiO 4 Br 2 phosphor shows a strong blue emission band centered at 469 nm under 365 nm UV light, which demonstrates that Ca 3 SiO 4 Br 2 :Eu 2 + is a promising blue phosphor for use in white light LEDs.