Color tunable emission in Ce3+ and Tb3+ co-doped Ba2Ln(BO3)2Cl (Ln=Gd and Y) phosphors for white light-emitting diodes

• Published in: Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy Vol. 116; pp. 556 - 561
• Main Authors: Zhang, Niumiao, Guo, Chongfeng, Jing, Heng, Jeong, Jung Hyun
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.12.2013
• Subjects: Luminescence; Optical property; Phosphor; Optical property; Phosphor; Luminescence
• ISSN: 1386-1425
• DOI: 10.1016/j.saa.2013.07.076

PL spectra of (a) Ba2Y(BO3)2Cl:0.03Ce3+, mTb3+, (b) Ba2Gd(BO3)2Cl:0.01Ce3+, nTb3+ with different Tb3+ contents and (c) the corresponding energy-level diagram. Insets: Dependence of PL intensity of Ce3+ and Tb3+ on the concentrations of Tb3+. •Ce3+ and Tb3+ co-doped chloroborates Ba2Ln(BO3)2Cl (Ln=Y, Gd) green emitting phosphors were prepared.•Luminescent properties of these phosphors were investigated by comparing methods.•Energy transfer between Ce3+ and Tb3+ were discussed in detail. Ce3+ and Tb3+ co-doped Ba2Ln(BO3)2Cl (Ln=Y and Gd) green emitting phosphors were prepared by solid state reaction in reductive atmosphere. The emission and excitation spectra as well as luminescence decays were investigated, showing the occurrence of efficient energy transfer from Ce3+ to Tb3+ in this system. The phosphors exhibit both a blue emission from Ce3+ and a green emission from Tb3+ under near ultraviolet light excitation with 325–375nm wavelength. Emission colors of phosphors could be tuned from deep blue through cyan to green by adjusting the Tb3+ concentrations. The energy transfer efficiency and emission intensity of Ba2Y(BO3)2Cl:Ce3+, Tb3+ precede those of Ba2Gd(BO3)2Cl:Ce3+, Tb3+, and the sample Ba2Y(BO3)2Cl:0.03Ce3+, 0.10Tb3+ is the best candidate for n-UV LEDs.