Photoluminescence properties and thermal stability of RE2-xEuxSn2O7 (RE = Y3+, Gd3+, Lu3+) red nanophosphors: An experimental and theoretical study

Abstract

Defect-fluorite structured Eu 3+ -doped Y 2 Sn 2 O 7 nanoparticles (30–40 nm) were successfully prepared through a facile co-precipitation method without any organic additives or templates followed by calcination in air. Luminescent properties of the as-prepared Y 2-x Eu x Sn 2 O 7 (0.02 ≤ x ≤ 0.6) nanophosphors were fully characterized from an experimental and theoretical point of view (excitation, emission, lifetime, critical concentration, temperature-dependent luminescence and thermal stability, type of interactions and the Judd-Ofelt analysis). The nanophosphors showed relatively sharp excitation bands from 360 to 530 nm and exhibited characteristic emission bands with the most intensive emission centered at 612 nm. In addition, Gd 1.98 Eu 0.02 Sn 2 O 7 and Lu 1.98 Eu 0.02 Sn 2 O 7 samples were prepared in order to study how substitution of RE 3+ (Y 3+ with Gd 3+ and Lu 3+ ions) influences on luminescent properties of RE 1.98 Eu 0.02 Sn 2 O 7 and thermal stability of their luminescence. In order to understand better luminescent properties, the Judd–Ofelt analysis was applied to all the synthesized powders. The highest value of quantum efficiency, ~96%, was estimated for Lu 1.98 Eu 0.02 Sn 2 O 7 . To assess potential application in high-power LEDs, the temperature-dependent emission spectra of Y 1.98 Eu 0.02 Sn 2 O 7 , Gd 1.98 Eu 0.02 Sn 2 O 7 and Lu 1.98 Eu 0.02 Sn 2 O 7 nanophosphors were studied. © 2019 Elsevier B.V.