Ca3Al2(SiO4)3−δCl4δ:Eu2+, Mn2+: A potential phosphor with energy transfer for near-UV pumped white-LEDs

✍ Scribed by Wei Lü; Zhendong Hao; Xia Zhang; Xingyuan Liu; Xiaojun Wang; Jiahua Zhang

• Publisher: Elsevier Science
• Year: 2011
• Tongue: English
• Weight: 633 KB
• Volume: 33
• Category: Article
• ISSN: 0925-3467
• DOI: 10.1016/j.optmat.2011.02.025

✦ Synopsis

A series of Eu 2+ and Mn 2+ coactivated Ca 3 Al 2 (SiO 4 ) 3Àd Cl 4d phosphors have been synthesized by solid state reactions and their luminescence properties have been investigated by means of powder diffuse reflection, photoluminescence excitation and emission spectra, and lifetimes. The phosphor Ca 3 Al 2 (SiO 4 ) 3Àd Cl 4d :Eu 2+ , Mn 2+ exhibits two dominating bands situated at 460 and 550 nm, originate from the allowed 5d ? 4f transition of the Eu 2+ ion and the 4 T 1g (4G) ? 6 A 1g (6S) transition of the Mn 2+ ion, respectively. We have discovered that energy transfers from Eu 2+ to Mn 2+ by directly observing significant overlap of the excitation spectrum of Mn 2+ and the emission spectrum of Eu 2+ as well as the decline of lifetimes of Eu 2+ . By utilizing the principle of energy transfer, we have demonstrated that with appropriate tuning of activator content Ca 3 Al 2 (SiO 4 ) 3Àd Cl 4d :Eu 2+ , Mn 2+ phosphors exhibit potential to act as a phosphor for near ultraviolet light-emitting diodes.