Selective Crystallization of Four Tungstates (La2 W3 O12 , La2 W2 O9 , La14 W8 O45 , and La6 W2 O15 ) via Hydrothermal Reaction and Comparative Study of Eu3+ Luminescence

Inorganic Chemistry
Xiaofei ShiJi-Guang Li

Abstract

Hydrothermal reaction at 200 °C was systematically undertaken in wide ranges of solution pH (4-13) and W/La molar ratio ( R = 0.5-2), without using any organic additive, to investigate the effect of hydrothermal parameter on product property and the underlying mechanism. Combined analysis by X-ray diffraction (XRD), inductively coupled plasma (ICP) spectroscopy, elemental mapping, scanning electron microscopy (SEM) and transmission electron microscopy (TEM) revealed that either a decreasing pH or increasing R value yielded a product richer in W and, conversely, richer in La. The results were interpreted from the solution chemistry of La3+ and tungstate ions. As an outcome of our 40 well-designed experiments, four La tungstates-La2W3O12, La2W2O9, La14W8O45, and La6W2O15-were successfully obtained in a phase-pure form by calcining their hydrothermal precursors. Phase and morphology evolution, structure features, and properties of Eu3+ emission were, for the first time, comparatively investigated for the four compounds. Spectral analysis found that the 5 at. % Eu3+-doped La2W3O12 phosphor exhibits the highest quantum efficiency (∼47%), more red component, and the shortest fluorescence lifetime of luminescence (∼0.72 ms).

References

Dec 14, 2005·Journal of Hazardous Materials·A KoutsospyrosN Strigul
Dec 1, 1991·Talanta·P M May, K Murray
Mar 21, 2012·Dalton Transactions : an International Journal of Inorganic Chemistry·Shaohua HuangPiaoping Yang
Dec 12, 2012·Angewandte Chemie·Datao TuXueyuan Chen
Feb 22, 2013·Dalton Transactions : an International Journal of Inorganic Chemistry·Anna M KaczmarekRik Van Deun
Jul 5, 2013·Dalton Transactions : an International Journal of Inorganic Chemistry·Xiaolin LiuQingming Shen
Sep 18, 2013·Chemical Society Reviews·Anna M Kaczmarek, Rik Van Deun
Mar 29, 2014·Acta Crystallographica Section B, Structural Science, Crystal Engineering and Materials·Loïc PatoutChristine Leroux
May 9, 2015·Dalton Transactions : an International Journal of Inorganic Chemistry·Anna M KaczmarekRik Van Deun
Aug 1, 2015·Dalton Transactions : an International Journal of Inorganic Chemistry·Rik Van DeunAnna M Kaczmarek
Feb 24, 2016·Dalton Transactions : an International Journal of Inorganic Chemistry·Zhihao WangXudong Sun

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