Photoluminescence and electron-vibrational interaction in 5d state of Eu2+ ion in Ca3Al2O6 down-conversion phosphor. (October 2021)

• Record Type: Journal Article
• Authors: Parauha, Yatish R.; Dhoble, S.J.
• Is Part Of: Optics & laser technology. Volume 142(2021)
• Publication Date: 2021-10
• Subjects: Solid-state reaction method -- Photoluminescence -- CIE chromaticity diagram -- Electron-Vibrational Interaction parameters; Optics -- Periodicals; Lasers -- Periodicals; Electronic journals; 621.366
• DOI: 10.1016/j.optlastec.2021.107191
• Languages: English
• ISSNs: 0030-3992

Abstract

Graphical abstract: A novel blue-emitting Ca3 Al2 O6 : Eu 2+ phosphor was synthesized, its crystal structure luminescence properties, and EVI parameter have been investigated. Highlights: Novel Eu 2+ activated Ca3 Al2 O6 phosphor was successfully prepared by the solid state reaction method. Under 334 nm excitation, PL emission spectra revealed a strong emission band around blue color at 445 nm. The optimal doping concentration of Eu 2+ ion was 0.5 mol%. This CIE diagram represents (0.2127, 0.1102) coordinate in blue region and 84.21% color purity. The blue phosphors can act as a promising candidate for WLEDs application. Abstract: In the present work, a series of Eu 2+ activated Ca3 Al2 O6 down-conversion phosphors have been successfully prepared via solid-state reaction method at 800 °C. Under 334 nm excitation, PL emission spectra shows broad band emission with the peak centred at 445 nm. This broad band emission is assigned to the allowed 4f 6 5d 1 → 4f 7 electronic transition of Eu 2+ ions. The highest emission intensity was observed for Ca3 Al2 O6 : 0.5 mol%Eu 2+ phosphor. The CIE chromaticity diagram shows high colour purity and excellent chromaticity coordinates. This CIE diagram reveals (0.2127, 0.1102) chromaticity coordinates in the blue region with 84.21% colour purity. Further, the electron-vibrational interaction parameters such as Stokes shift, Huang-Rhys factor, effective phonon energy, zero phonon line position, and red shift have been calculated using a spectrum fitting method. These results indicate that the Eu 2+ activated Ca3 Al2 O6 down-conversion phosphor has great potential in the field of white LEDs.