Multicolor-tunable up-conversion emissions of Yb3+,Er3+/Ho3+ co-doped Ba3Lu2Zn5O11: crystal structure, luminescence and energy transfer properties

Dalton Trans. 2019 Feb 26;48(9):2917-2925. doi: 10.1039/c8dt04577a.

Abstract

Yb3+-Er3+ and Yb3+-Ho3+ co-doped Ba3Lu2Zn5O11 phosphors were successfully obtained. The structure of the as-synthesized phosphor was determined by Rietveld refinement. The up-conversion (UC) spectra of Ba3Lu2Zn5O11:Yb3+,Er3+ exhibits two prominent emission bands centered at 560 and 663 nm, which originate from the 2H11/2/4S3/2 → 4I15/2 and 4F9/2 → 4I15/2 transitions of Er3+, respectively. Ba3Lu2Zn5O11:Yb3+,Ho3+ revealed a bright green emission at around 553 nm and negligible red emission peaking at 660 nm, which were assigned to the 5F4/5S2 → 5I8 and 5F5 → 5I8 transitions of Ho3+, respectively. The up-conversion luminescence of the samples was studied as a function of the concentration of the dopants. The origin of the UC mechanism is discussed in detail by analyzing energy-level diagrams, the dependence of the UC emission intensity on pump power, and the lifetimes. The results indicate that the Ba3Lu2Zn5O11:Yb3+,Er3+/Ho3+ phosphors are excellent up-conversion emitters and have potential applications in display and illumination technologies.