Citric based sol–gel synthesis and luminescence characteristics of CaLa2ZnO5:Eu3+phosphors for blue LED excited white LEDs

• Published in: Journal of alloys and compounds 2012-01, Vol.512 (1), p.264-269
• Main Authors: Bandi, Vengala Rao, Grandhe, Bhaskar Kumar, Jang, Kiwan, Lee, Ho-Sueb, Shin, Dong-Soo, Yi, Soung-Soo, Jeong, Jung-Hyun
• Format: Article
• Language: English
• Subjects: Condensed matter: electronic structure, electrical, magnetic, and optical properties; Emission; Emission analysis; Exact sciences and technology; Excitation; Light-emitting diodes; Luminescence; Optical properties; Optical properties and condensed-matter spectroscopy and other interactions of matter with particles and radiation; Other solid inorganic materials; Oxide materials; Phosphors; Photoluminescence; Physics; Sol–gel processes; White light
• ISSN: 0925-8388; 1873-4669
• DOI: 10.1016/j.jallcom.2011.09.078

► We had synthesized a novel class of orange–red phosphors namely Eu3+:CaLa2ZnO5 phosphor. ► Eu3+:CaLa2ZnO5 is having CIE coordinates nearer to NTSC recommendations for a red phosphor. ► It could be excited efficiently with the GaN based blue light-emitting diode (LED) chip. A novel class of orange–red phosphors namely CaLa2ZnO5 (CLZ) doped with Eu3+ ions were prepared by adopting citrate based sol–gel method. Those were thoroughly characterized by means of XRD, SEM, Tg-DTA, photoluminescent (PL) spectral profiles. PL studies reveal that its emission intensity strongly depends on sintering temperature as well as the dopant ion (Eu3+) concentration. Eu3+ ion doped CaLa2ZnO5 phosphor has a strong excitation at 468nm, which correspond to the popular emission line from a GaN based blue light-emitting diode (LED) chip. The influence of the preparation method on the luminescence property was studied by comparing the emission performance of phosphors prepared by sol–gel and solid-state reaction methods along with a commercial red phosphor Y2O2S:Eu3+. Thus, the intense red emission (5D0→7F2) of the Eu3+ doped CLZ phosphors under blue excitation suggests them to be a potential candidate for the production of white light by blue LEDs.