Golja Desta R, Dejene Francis B, Kim Jung Yong
Department of Materials Science and Engineering, Jimma Institute of Technology, Jimma University, PO Box 378, Jimma, Ethiopia.
Department of Physics, University of the Free State (QwaQwa Campus), PO Box 339, Bloemfontein, South Africa.
J Phys Condens Matter. 2022 May 19;34(29). doi: 10.1088/1361-648X/ac6d99.
Trivalent dysprosium/europium-codoped silicate phosphors (BaCaSiO:Dy/Eu) were prepared as a function of Euconcentration (= 0.03 and= 0.01-0.05). The phosphors showed the averaged crystallite size of ∼37.2 ± 1.3 nm and displayed nano-/micro-scale grains with some void defects. The energy bandgap is about 4.3 eV for co-doped samples and 3.2 eV for the silicate host. The photoluminescence spectra indicated that the presence of Euions enhanced the red light emission, and the emission peaks located at the versatile wavelengths of 482, 577, 592, 614, 652, and 703 nm. Then, the internal quantum efficiencies were estimated by using the Judd-Ofelt model. Resultantly, the best quantum efficiency was ∼74% when the doping concentrations were 3 mol% Dyand 4 mol% Euions. Finally, the CIE coordinate data exhibited that the emission color could be tuned from white to reddish-orange by changing the Eucontents, proposing the applicability of BaCaSiO:Dy/Euphosphors to the solid-state lighting.