Enhancement of Eu²⁺ Luminescence in BaO-SiO₂ Compounds Through Composition Modification

ABSTRACT

Phosphors of Eu²⁺-doped BaO-SiO₂ compounds composed of a major BaSiO₃ phase and a minor Ba₂SiO₄ phase were synthesized by a solid-state method at 1200°C under CO atmosphere. An enhancement of the photoluminescence of Eu²⁺ up to 18 times has been achieved by mixing ZnO into the composition. The composition-optimized phosphor emits bright yellow–green luminescence with excitation between 380 and 420 nm, indicating potential of application in AlGaN-based UV-LEDs. Under the similar synthesis and measurement conditions, the emission band of the optimized phosphor is more intense and has stronger red component than that of Ba₂SiO₄:Eu²⁺. Our experimental results suggest that the addition of ZnO may retain and stabilize Eu²⁺ in BaSiO₃ crystalline lattice and thus may enhance the 5d-4f luminescence and eliminate Eu³⁺ 4f-4f transition.

KEYWORDS:

• luminescence enhancement
• phosphors
• silicates
• white LEDs

ACKNOWLEDGMENTS

Work performed at Argonne National Laboratory was supported by the U.S. Department of Energy, Office of Basic Energy Sciences, Division of Chemical Sciences, Geosciences, and Biosciences, under contract DE-AC02-06CH11357.

Notes

This article is part of the Special Issue on Spectroscopy of Lanthanide Materials II, published in volume 43(5) of Spectroscopy Letters.