Spectroscopic analysis of alkaline-earth metal (Mg, Ca, Sr and Ba) co-doped Gd2O3:Eu phosphors synthesized via co-precipitation route

Ruby Priya; O P Pandey

doi:10.1016/j.saa.2020.118078

Spectroscopic analysis of alkaline-earth metal (Mg, Ca, Sr and Ba) co-doped Gd₂O₃:Eu phosphors synthesized via co-precipitation route

Spectrochim Acta A Mol Biomol Spectrosc. 2020 Apr 15:231:118078. doi: 10.1016/j.saa.2020.118078. Epub 2020 Jan 17.

Authors

Ruby Priya¹, O P Pandey²

Affiliations

¹ Functional Materials Lab, School of Physics and Materials Science, Thapar Institute of Engineering & Technology, Patiala 147004, India.
² Functional Materials Lab, School of Physics and Materials Science, Thapar Institute of Engineering & Technology, Patiala 147004, India. Electronic address: oppandey@thapar.edu.

PMID: 32014656
DOI: 10.1016/j.saa.2020.118078

Abstract

This paper reports the effect of alkaline earth metals (AEM = Mg²⁺, Ca²⁺, Sr²⁺, Ba²⁺) co-doping on the structural, morphological and luminescent properties of Gd₂O₃:Eu phosphors. The concentration of the Eu³⁺ ions was fixed 4 mol% to avoid the chances of the concentration quenching. AEM co-doped Gd₂O₃:Eu XRD profile confirmed the synthesis of cubic-phase of all the co-doped samples. FESEM micrographs exhibited the rod like morphology of the synthesized phosphors. All the samples were irradiated under UV excitation and exhibited intense, sharp and narrow emission spectra corresponding to the characteristic transitions (⁵D₀ → ⁷F_1,2,3,4) transitions of Eu³⁺ ions. The photometric parameters such as CIE coordinates, CCT and color purity are calculated. In order to probe the further luminescent properties and influence of the of alkaline earth metals on the local environment of the Eu ions in the host lattice, spectral parameters are calculated from Judd Ofelt theory from emission spectra. The obtained results suggest that AEM can be effectively utilized to enhance the luminescence intensity even after concentration quenching. The as-synthesized phosphors can be used in various solid state lighting devices and bio-sensors.

Keywords: Alkaline earth metals; Europium; Gd(2)O(3); Judd-Ofelt; Luminescence.