Luminescence properties of Eu2+ doped BaAl2Si2O8 phosphor for white LEDs

Abstract

The BaAl 2 Si 2 O 8 :Eu 2+ blue emitting phosphor was obtained through the one-step calcination process of precursors prepared by chemical co-precipitation method. The phase structure and luminescence propertied of the phosphor were investigated using X-ray diffraction (XRD) and a fluorescence spectrophotometer. The excitation spectrum exhibited a broad band between 230 nm and 400 nm and the emission peaking at about 470 nm was observed, which originated from the allowed f-d transition of Eu 2+ ions at Ba 2+ sites. Owing to the different optimal concentrations under different excitation wavelengths (254 nm and 365 nm), the energy-transfer mechanism in this phosphor has changed from the dipole-dipole interaction to the exchange interaction of Eu 2+ ions. phosphor, BaAl 2 Si 2 O 8 :Eu 2+ , luminescence properties, white LED PACS: 78.55.Hx, 42.55.Px

Improved photoluminescence properties of BaAl 2 Si 2 O 8 :Eu 3+ ,Tb 3+ phosphors by doping Tb 3+

“…1(a). All the diffraction patterns are matched with JCPDS card 77-0185, revealing the hexagonal crystal structure with P6/mmm space group [13]. There are three different cation sites in the BaAl 2 Si 2 O 8 host, i.e., a twelve-coordinated Ba 2+ and two seven-coordinated Al 3+ and Si 4+ [7,13].…”

“…All the diffraction patterns are matched with JCPDS card 77-0185, revealing the hexagonal crystal structure with P6/mmm space group [13]. There are three different cation sites in the BaAl 2 Si 2 O 8 host, i.e., a twelve-coordinated Ba 2+ and two seven-coordinated Al 3+ and Si 4+ [7,13]. The ionic radius of Eu 3+ (1.066 Å) and Tb 3+ (1.04 Å) is closer to that of Ba 2+ (1.42 Å) in comparison with that of Al 3+ (0.39 Å) and Si 4+ (0.26 Å) [7,[14][15][16].…”

Effect of CeO2 Doping on Phase Structure and Microstructure of AlCoCuFeMnNi Alloy Coating

“…Besides, the contents of all elements except for Ce are equal. Therefore, the lattice expansion causes the diffraction peaks to shift toward a small angular direction 18,19 .…”

Enhanced photoluminescence properties of red emitting Ba1−xAl2Si2O8:xEu3+ phosphors by charge compensation

“…The white LEDs have widely been used for backlighting, solidstate lasers, traffic signals, decoration, and textile printing. 5,6 Furthermore, the white LEDs are expected to replace the widely used incandescent and fluorescent lamps in the near future. Typically, commercial white LEDs use a combination of a blue InGaN chip and a yellow Y3Al5O12:Ce 3+ (YAG:Ce 3+ ) phosphor.…”

“…At present, among the existing lighting technologies, white light-emitting diodes (LEDs) are recognized as future lighting technology due to their excellent properties, including high energy efficiency, high brightness, low power consumption, long lifetime, small size, and environmentalfriendliness. [5][6][7] LEDs are solid-state semiconductor devices that directly convert electrical energy into light. The white LEDs have widely been used for backlighting, solid-state lasers, traffic signals, decoration, and textile printing.…”