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Published on: May 10, 2021
Crystal structure and pale-yellow emitting properties of K3Gd1-xDyxB6O12 solid solutions
Rui Juan Zhang1, Jian Chao Shi1, Dan Dan Zhao1
1College of Chemistry and Chemical Engineering, Henan Polytechnic University, Jiaozuo, Henan 454000, People's Republic of China.
Abstract:
A new potassium dysprosium polyborate, K3DyB6O12, has been prepared via the high-temperature molten salt method and structurally characterized by single-crystal X-ray diffraction analysis. The structure can be described as a three-dimensional framework composed of isolated bicyclic [B5O10]5- groups and Dy3+ and K+ ions. The Fourier transform IR (FT-IR) and ultraviolet-visible (UV-Vis) spectra were investigated. A series of K3Gd1-xDyxB6O12 phosphors was prepared and their photoluminescence properties were studied. The K3Gd1-xDyxB6O12 phosphors exhibit a strong yellow emission band at 577 nm (the 4F9/2→6H13/2 transition of Dy3+) under UV excitation of 275 nm (the 8S7/2→6IJ transition of Gd3+), suggesting the occurrence of the energy transfer Gd3+→Dy3+. The optimized doping concentration of the Dy3+ ion was 8 mol%. We may expect that K3Gd1-xDyxB6O12 is a promising pale-yellow emission phosphor for visual displays or solid-state lighting.
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