Abstract

Precursor of Europium doped calcium aluminate (CaAl2O4: Eu) was prepared by the Pechini technique. The synthesized samples were calcined at 900–1500°C for 2h in air atmosphere. The crystal structures of calcined samples at low and high temperatures were found to be the metastable hexagonal and stable monoclinic systems by X-ray powder diffraction (XRD) analysis, respectively. The effects of Eu content and valence state on the luminescence characteristics of CaAl2O4: Eu were studied by luminescence spectrometer (LS). With the increase in calcination temperature, the phosphors exhibited color change from bright red to violet upon excitation by UV-light and an abnormal reduction of Eu3+→Eu2+ was observed in monoclinic phase of CaAl2O4: Eu that calcined in air atmosphere at high temperature. The reduction mechanism was explained reasonably by a rigid three-dimensional framework structure of the stable monoclinic phase of CaAl2O4: Eu and a charge compensation model.

Full Text
Paper version not known

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.