A novel single-phase warm white emission phosphor Sr3YAl2O7.5:Bi3+,Eu3+ with energy transfer for UV white LEDs

作者：Wang, Yichao; Ding, Jianyan; Li, Yanyan; Yang, Linfen; Ding, Xin; Wang, Yuhua

来源：RSC Advances, 2016, 6(48): 42618-42626.

DOI：10.1039/c6ra05445e

• CRYSTAL-STRUCTURE
• LIGHT
• PHOTOLUMINESCENCE
• TB3+
• MN2+
• EU3+

A novel phosphor Sr3YAl2O7.5:xBi(3+),yEu(3+) was successfully synthesized through a high temperature solid-state reaction. The crystal structure, photoluminescence properties, fluorescence decay and thermal quenching properties have been measured and analyzed. The energy transfer mechanism is demonstrated to be a dipole-dipole interaction and the critical distance between the Bi3+ and Eu3+ has been calculated. The emission spectra of the Sr3YAl2O7.5:Bi3+,Eu3+ phosphors present a blue-green emission of Bi3+ ions with three broad bands at 370 nm, 410 nm and 505 nm and many characteristic emission lines of Eu3+ ions, deriving from the allowed P-3(1)-S-1(0) transition of the Bi3+ ion and the D-5(0)-F-7(j) transition of the Eu3+ ion. By changing the ratio of Bi3+ concentration and Eu3+ concentration, we can get a warm white light under ultraviolet excitation. The results give the Commission International deL'Eclairage (CIE) chromaticity coordinates for the white LED as (0.3794, 0.3453) and a correlated color temperature of 3731 K, and the integrated emission intensity at 150 degrees C remains 66.4% of that measured at room temperature, which indicates that the SYAO:Bi3+,Eu3+ phosphor is a very promising candidate for use as a warm UV white light-emitting diode (WLED) phosphor.

• 出版日期2016
• 单位兰州大学