Nd3+doped- SiO2–KLaF4 oxyfluoride glass-ceramics prepared by sol-gel

Transparent oxyfluoride glass-ceramic films and self-supported layers with composition 80SiO2-20LaF3 doped with Er3+ have been successfully synthesized by sol-gel process for the first time. Crack-free films and self-supported layer with a maximum thickness up to 1.4 µm were obtained after heat treatment at the low temperature of 550 °C for 1 min, resulting in a LaF3 crystal fraction of 18 wt%, as confirmed by quantitative Rietveld refinement. This is the highest value reported up to now for transparent oxyfluoride glass-ceramics prepared by sol-gel. This work provides a new synthesis strategy and opens the way to a wide range of potential applications of oxyfluoride glass-ceramics. The characterization by a wide range of techniques revealed the homogeneous precipitation of LaF3 nanocrystals into the glass matrix. X-ray absorption spectroscopy and electron paramagnetic resonance confirmed that the Er3+ ions are preferentially embedded in the low phonon-energy LaF3 nanocrystals. Moreover, photoluminescence (PL) measurements confirmed the incorporation of dopants in the LaF3 nanocrystals. The effective concentration of rare-earth ions in the LaF3 nanocrystals is also estimated by X-ray absorption spectroscopy.

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Rare-earth doped sol–gel derived oxyfluoride glass–ceramics: Structural and optical characterization

Optical Materials ◽

10.1016/j.optmat.2011.06.004 ◽

2011 ◽

Vol 33 (11) ◽

pp. 1770-1774 ◽

Cited By ~ 13

Author(s):

C.E. Secu ◽

M. Secu ◽

C. Ghica ◽

L. Mihut

Keyword(s):

Rare Earth ◽

Sol Gel ◽

Glass Ceramics ◽

Optical Characterization ◽

Oxyfluoride Glass ◽

Rare Earth Doped

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Extraction of Nd3+-doped LiYF4 phosphor from sol–gel-derived oxyfluoride glass ceramics by hydrofluoric acid treatment

Optical Materials ◽

10.1016/j.optmat.2013.07.015 ◽

2013 ◽

Vol 35 (11) ◽

pp. 1879-1881 ◽

Cited By ~ 2

Author(s):

G. Kawamura ◽

R. Yoshimura ◽

K. Ota ◽

S.Y. Oh ◽

H. Muto ◽

...

Keyword(s):

Hydrofluoric Acid ◽

Acid Treatment ◽

Sol Gel ◽

Glass Ceramics ◽

Oxyfluoride Glass

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Up-conversion luminescence of Er3+/Yb3+ co-doped LiYF4 nanocrystals in sol–gel derived oxyfluoride glass-ceramics

Journal of Non-Crystalline Solids ◽

10.1016/j.jnoncrysol.2015.07.010 ◽

2015 ◽

Vol 426 ◽

pp. 78-82 ◽

Cited By ~ 18

Author(s):

M. Secu ◽

C.E. Secu

Keyword(s):

Sol Gel ◽

Glass Ceramics ◽

Oxyfluoride Glass ◽

Co Doped

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Crystallization Process and Site-Selective Excitation of Nd3+ in LaF3/NaLaF4 Sol–Gel-Synthesized Transparent Glass-Ceramics

Crystals ◽

10.3390/cryst11050464 ◽

2021 ◽

Vol 11 (5) ◽

pp. 464

Author(s):

María E. Cruz ◽

Jing Li ◽

Giulio Gorni ◽

Alicia Durán ◽

Glenn C. Mather ◽

...

Keyword(s):

Crystallization Process ◽

Sol Gel ◽

Glass Ceramics ◽

X Ray Diffraction ◽

Oxyfluoride Glass ◽

Excitation Spectra ◽

Molar Ratios ◽

Transmission Electron ◽

Site Selective ◽

First Time

In this study, transparent oxyfluoride glass-ceramics (GCs) with NaLaF4 nanocrystals (NCs) were prepared by the sol–gel method for the first time. Three different molar ratios of La(CH3COO)3/Na(CH3COO) were used to obtain the GCs, which were sintered at 450, 550 and 650 °C for 1 min. X-ray diffraction (XRD) was employed to follow the evolution of the xerogel during the heat treatments and to study crystal growth for the three temperatures. In all cases, the LaF3 crystalline phase was present, but crystallization of NaLaF4 was only promoted at 650 °C. Thermogravimetric and thermodifferential analysis (TGA-DTA) and Fourier transform infrared spectroscopy (FTIR) were used to analyze the crystallization process. High-resolution transmission electron microscopy (HRTEM) was employed to confirm NaLaF4 crystallization and determine the size distribution. The incorporation of Nd3+ ion into NaLaF4 and LaF3 nanocrystals was confirmed by site-selective emission and excitation spectra. The Nd3+ emission intensities in both phases depend not only on the NaLaF4/LaF3 ratio but also on their emission efficiencies.

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