Probing Solvation-Shell Hydrogen Binding in Glassy and Sol−Gel Matrixes through Vibronic Sideband Luminescence Spectroscopy

ABSTRACTA Y2O3-SiO2 nanocomposite doped with Eu3+ was obtained by a sol-gel method and characterized by X-ray diffraction, IR, 29Si NMR and laser-excited luminescence spectroscopy. It was found that small (2-3 nm) yttria nanoparticles are homogeneously dispersed in, and interacting with, the amorphous silica matrix. Luminescence spectroscopy indicates that the Eu3+ ion is preferentially located inside or at the surface of highly disordered Y2O3 nanoparticles. These luminescent nanocomposites form a class of materials which could find applications in the field of phosphors.

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Study on the energy transfer between UO2+2 and Eu3+ in sol-gel derived titania matrix by luminescence spectroscopy

Chinese Journal of Chemistry ◽

10.1002/cjoc.19990170206 ◽

2010 ◽

Vol 17 (2) ◽

pp. 132-136 ◽

Cited By ~ 4

Author(s):

Lan-She Fu ◽

Hong-Jie Zhang ◽

Shu-Bin Wang ◽

Qing-Guo Meng ◽

Kui-Yue Yang ◽

...

Keyword(s):

Energy Transfer ◽

Sol Gel ◽

Luminescence Spectroscopy

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Sol-Gel Synthesis and Characterization of BaAl2O4 and Co: BaAl2O4 Nanoparticles

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.148-149.1067 ◽

2010 ◽

Vol 148-149 ◽

pp. 1067-1070 ◽

Cited By ~ 1

Author(s):

Cai Na Luan ◽

Jin Ma ◽

Zhen Zhu ◽

Ling Yi Kong ◽

Qiao Qun Yu

Keyword(s):

Sol Gel ◽

Visible Region ◽

Emission Spectra ◽

Chelating Agent ◽

Nano Particles ◽

Luminescence Spectroscopy ◽

Metal Nitrates ◽

Heat Treated ◽

Nano Crystal ◽

Sol Gel Synthesis

In this paper, we prepared BaAl2O4 and Co:BaAl2O4 nanoparticles from aqueous solution of metal nitrates containing citric acid as a chelating agent by sol-gel method. The gel was heat-treated at temperatures ranging from 710°C to 1000°C. The heat-treated powders were characterized by X-ray diffraction analysis (XRD), infrared spectra (IR) and luminescence spectroscopy. From the results of the characterization, we find the prepared powders are pure nano-particles of BaAl2O4 after heat-treated at 900°C temperature. The emission spectra of Co: BaAl2O4 in the visible region indicates the existence of Co2+ in the tetrahedral sites of BaAl2O4 nano-crystal.

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Functionalization of Sol-Gel Zirconia Composites with Europium Complexes

Zeitschrift für Naturforschung B ◽

10.5560/znb.2014-3261 ◽

2014 ◽

Vol 69 (2) ◽

pp. 224-230 ◽

Cited By ~ 3

Author(s):

Nina Danchova ◽

Stoyan Gutzov

Keyword(s):

Diffuse Reflectance ◽

Diffuse Reflectance Spectroscopy ◽

Sol Gel ◽

Reflectance Spectroscopy ◽

Luminescence Spectroscopy ◽

Quantum Yields ◽

X Ray Diffraction ◽

Europium Complexes ◽

X Ray ◽

Zirconia Composites

Different sol-gel strategies based on functionalization of ZrO2:Eu microparticles with 1,10- phenanthroline (phen) and incorporation of colloidal Eu(phen)2(NO3)3 into zirconia have been used to obtain hybrid sol-gel composites with controlled optical properties. The process leads to materials with quantum yields of about 48% monitoring the 615 nm emission line at 350 nm excitation. Excitation/ luminescence spectroscopy, diffuse reflectance spectroscopy and X-ray diffraction have been used to characterize the hybrid zirconia composites.

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The Optical Behavior of Organic and Organometallic Molecules in Sol-Gel Matrices

MRS Proceedings ◽

10.1557/proc-121-331 ◽

1988 ◽

Vol 121 ◽

Cited By ~ 18

Author(s):

B. Dunn ◽

E. Knobbe ◽

J. M. McKiernan ◽

J. C. Pouxviel ◽

J. I. Zink

Keyword(s):

Rhodamine 6G ◽

Sol Gel ◽

Optical Gain ◽

Luminescence Spectroscopy ◽

Subsequent Aging ◽

Organometallic Molecules ◽

Sol Gel Transition ◽

Optical Behavior ◽

Gel Processing ◽

Gel Transition

ABSTRACTThe low temperatures involved in sol-gel processing have enabled organic and organometallic molecules to be incorporated in gel matrices. These molecules serve as optical probes to characterize gel chemistry and structure. The present paper describes the use of luminescence spectroscopy to detail matrix rigidity effects and protonation/deprotonation reactions during the sol-gel transition and subsequent aging processes. In separate experiments, the addition of a laser dye, rhodamine 6G, has enabled us to demonstrate lasing and optical gain in a silica gel.

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Luminescence Properties of Eu- and Mg-Codoped Sol-Gel SiO2 Glasses

ISRN Nanotechnology ◽

10.5402/2012/298694 ◽

2012 ◽

Vol 2012 ◽

pp. 1-5 ◽

Cited By ~ 2

Author(s):

Martin O. Onani ◽

Paul Mushonga ◽

Lehlohonolo F. Koao ◽

Francis B. Dejene

Keyword(s):

Uv Light ◽

Sol Gel ◽

Silica Matrix ◽

Luminescence Spectroscopy ◽

X Ray Diffraction ◽

Light Excitation ◽

Uv Lamp ◽

Hydrolysis Of ◽

Excited Luminescence ◽

The Eu

A series of SiO2 nanostructures codoped with Eu3+; Mg2+ ions were obtained by a sol-gel method. The gels synthesized by the hydrolysis of Si(OC2H5)4, Eu(NO3)3·6H2O, and Mg(NO3)2 were heated in air at 600°C for 2 hours. Firstly, the total amount of Eu3+ ions was varied from 0 to 2.0 mol% to investigate the effect of self-damping, while in the second case, the Eu3+ ions were kept constant in the experiment at 0.5 mol% total doping and Mg2+ ions varied. The samples were characterized by X-ray diffraction, TEM, EDS, and UV lamp-excited luminescence spectroscopy. The Eu3+ ions were homogeneously dispersed in the silica and interacting with the small (1–5 nm) amorphous silica matrix. Strong red emissions located at 614 nm and 590 nm for doped and codoped SiO2 were observed from the UV light excitation at room temperature. The composition of around 1.25 mol% Eu3+ gave highest emission intensity. SiO2; Mg2+ ions portray strongly enhanced emissions due to energy transfer from Mg2+ to Eu3+, which is due to radiative recombination. An increase in luminescence intensity was observed as the Mg2+-to-Eu3+ ratio increased for the range investigated. The results show Eu3+ ion is located inside or at the surface of disordered SiO2 nanoparticles.

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Energy Transfer And Emission Processes In Sol-Gel Materials Doped With Europium (III) Complexes

MRS Proceedings ◽

10.1557/proc-328-745 ◽

1993 ◽

Vol 328 ◽

Author(s):

Xiao-Jun Wang ◽

Lowell R. Matthews ◽

E. T. Knobbet

Keyword(s):

Energy Transfer ◽

Sol Gel ◽

Optical Emission ◽

Luminescence Spectroscopy ◽

Dynamic Processes ◽

Time Resolved ◽

Transfer Rates ◽

Transfer Processes ◽

Emission Behavior ◽

Host Matrices

ABSTRACTOptical emission behavior in sol-gel-derived Materials doped with tris (4,4,4-trifluoro-l- (2′-thienyl) -l,3-butanedionato-O,O′)europium (III), Eu (ttfa)3, has been investigated by exciting the electronic levels of both europium (III) and the β-diketonate ligand (ttfa-). Energy transfer processes between the ttfa− ligands and europium (III) have been studied by time-resolved luminescence spectroscopy. The dynamic processes were compared in three sol-gel-derived host Matrices (silica, an acrylate ORMOSIL, and an epoxide ORMOSIL). Concentration dependence of the energy transfer rates was also studied.

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