Synthesis of Mn2+ Doped CdS Nanocrystals Embedded in a Sol-Gel Silica Matrix: Characterization of the Luminescence Activator

1996 ◽  
Vol 452 ◽  
Author(s):  
G. Counio ◽  
S. Esnouf ◽  
T. Gacoin ◽  
P. Barboux ◽  
A. Hofstaetter ◽  
...  
Keyword(s):  
Energy Transfer ◽  
Quantum Yield ◽  
Sol Gel ◽  
Silica Matrix ◽  
Silica Xerogels ◽  
Cds Nanocrystals ◽  
Bright Luminescence

AbstractMn2+-doped CdS nanocrystals (1.2 to 2.4 nm in diameter) embedded in organic-inorganic silica xerogels have been synthesized. Extensive studies (EXAFS, ESR and ENDOR) allow us to localize the ions responsible for the bright luminescence observed in such materials (quantum yield of 7%). The average number of Mn2+ per nanocrystal is in the 0.2–0.8 range, and the emission arises from an energy transfer from surface trapped carriers to Mn2+ ions.

Synthesis and luminescence properties of colloidal lanthanide doped YVO4

2001 ◽  
Vol 667 ◽  
Author(s):  
Arnaud Huignard ◽  
Thierry Gacoin ◽  
Frédéric Chaput ◽  
Jean-Pierre Boilot ◽  
Patrick Aschehoug ◽  
...  
Keyword(s):  
Quantum Yield ◽  
Room Temperature ◽  
Sol Gel ◽  
Precursor Solution ◽  
Silica Matrix ◽  
Luminescence Quantum Yield ◽  
Colloidal Solutions ◽  
Silicon Alkoxide ◽  
Crystalline Defects ◽  
Hydroxylated Surface

ABSTRACTAqueous colloidal solutions of well dispersed YVO4:Ln (Ln = Eu, Nd) nanoparticles are synthesized through precipitation reactions at room temperature. In the case of YVO4:Eu, a luminescence quantum yield of 15% is found, which is not as high as in the bulk due to the existence of residual crystalline defects and nonradiative relaxations from the hydroxylated surface. Appropriate hydrothermal annealing and deuteration of the surface allow to rise the yield up to 38%. Incorporation of the nanocrystals into a transparent silica matrix is achieved through preliminary coating of the particles with a functionnalized silicon alkoxide and further dispersion into a sol-gel precursor solution. Such sol-gel materials doped with YVO4:Nd nanocrystals are transparent and exhibit the typical emission at 1.06 μm of the Nd3+ ion.

scholarly journals Photophysical Challenges and Antenna Effect Between Click Reaction-based Bodipy Derivatives Manufactured From Knorr Pyrrole

2021 ◽  
Author(s):  
ahmed nuri kursunlu ◽  
Akif Kagan Yilmaz ◽  
Elif Bastug ◽  
Ersin Guler
Keyword(s):  
Energy Transfer ◽  
Quantum Yield ◽  
Absorption Coefficient ◽  
Organic Solvents ◽  
Click Reaction ◽  
Photophysical Properties ◽  
Molar Absorption Coefficient ◽  
Antenna Effect ◽  
Preliminary Study

Abstract In this paper, a series of click reaction-based Bodipy derivatives have been synthesized as part of a preliminary study. Following the characterization of the four challenger molecules, the photophysical properties (absorption, emission, excitation, molar absorption coefficient, quantum yield, etc.) were examined in various organic solvents. The results showed that the energy transfer from the Bodipy cores to other moieties was calculated between 71% and 93% depending on different π-electron configurations and chromophore groups.

Sol-Gel Elaboration and Optical Features of Eu3+-Doped CdS Nanocrystals in SiO2

2007 ◽  
Vol 555 ◽  
pp. 389-393 ◽  
Author(s):  
B. Julián ◽  
J. Planelles ◽  
E. Cordoncillo ◽  
P. Escribano ◽  
C. Sanchez ◽  
...  
Keyword(s):  
Sol Gel ◽  
Silica Matrix ◽  
Cds Nanoparticles ◽  
Rare Earth Ion ◽  
Sio2 Matrix ◽  
Chemical Homogeneity ◽  
Synthesis Conditions ◽  
Cds Nanocrystals ◽  
Back Transfer

In this work, Eu3+-doped CdS nanocrystals embedded in a SiO2 matrix were synthesised by a sol-gel method since this method confers a great chemical homogeneity, and allows in-situ generation and controlled growth of CdS nanocrystals within the silica glass. The influence of the sol-gel conditions on the Eu3+ optical response has been investigated. The synthesis conditions can be varied to modify the structure of the material, and the dispersion of the rare earth ion, within the silica matrix. From the optical analysis an energy transfer appears from CdS nanoparticles to Eu3+ ions but also a back transfer Eu3+ to CdS nanoparticles is evidenced.

Synthesis and Characterization of CoFe2O4Nanoparticles Dispersed in a Silica Matrix by a Sol−Gel Autocombustion Method

2006 ◽  
Vol 18 (16) ◽  
pp. 3835-3842 ◽  
Author(s):  
C. Cannas ◽  
A. Musinu ◽  
D. Peddis ◽  
G. Piccaluga
Keyword(s):  
Sol Gel ◽  
Silica Matrix ◽  
Synthesis And Characterization

scholarly journals Synthesis and characterization of sol-gel derived ZnS : Mn2+ nanocrystallites embedded in a silica matrix

2002 ◽  
Vol 25 (3) ◽  
pp. 175-180 ◽  
Author(s):  
B. Bhattacharjee ◽  
D. Ganguli ◽  
K. IakoubovskII ◽  
A. Stesmans ◽  
S. Chaudhuri
Keyword(s):  
Sol Gel ◽  
Silica Matrix ◽  
Synthesis And Characterization

Sol-gel synthesis and characterization of CuO–based nanosystems

2002 ◽  
Vol 737 ◽  
Author(s):  
Lidia Armelao ◽  
Davide Barreca ◽  
Manuel Bertapelle ◽  
Gregorio Bottaro ◽  
Cinzia Sada ◽  
...  
Keyword(s):  
Photoelectron Spectroscopy ◽  
Sol Gel ◽  
Copper Acetate ◽  
Dip Coating ◽  
Silica Matrix ◽  
Synthesis And Characterization ◽  
Host Matrix ◽  
X Ray ◽  
Sol Gel Synthesis

ABSTRACTThis paper is focused on the sol-gel synthesis and characterization of CuO-based nanosystems both in the form of supported films and as guest nanoclusters embedded in a silica matrix. In both cases copper acetate (Cu(CH3COO)2 · H2O) was used as Cu source and, for the CuO :SiO2 nanocomposite systems, tetraethoxysilane (Si(OC2H5)4, TEOS) was adopted as silica precursor. Films were obtained by a dip-coating procedure and subsequently treated in air between 100 and 900°C. The system evolution on thermal annealing was studied by X-ray photoelectron spectroscopy (XPS), Glancing-Incidence X-ray diffraction (GIXRD) and optical absorption. Irrespective of the processing conditions, the formation of tenorite (CuO) crystallites with nanometric dimension was observed. In the nanocomposite samples, copper was homogeneously distributed in the host matrix and stable CuO nanoclusters (φ ≈ 15 nm) were obtained.

scholarly journals Diarylphosphate as a New Route for Design of Highly Luminescent Ln Complexes

Molecules ◽  
2020 ◽  
Vol 25 (17) ◽  
pp. 3934
Author(s):  
Alexey E. Kalugin ◽  
Mikhail E. Minyaev ◽  
Lada N. Puntus ◽  
Ilya V. Taydakov ◽  
Evgenia A. Varaksina ◽  
...  
Keyword(s):  
Energy Transfer ◽  
Quantum Yield ◽  
Coordination Sphere ◽  
Near Infrared ◽  
Photophysical Properties ◽  
Transfer Scheme ◽  
Chloride Complexes ◽  
Very High ◽  
Bright Luminescence ◽  
The Eu

Organophosphate-chloride complexes [{(2,6-iPr2C6H3-O)2POO}2LnCl(CH3OH)4]·2CH3OH, Ln = Nd (1), Eu (2), Gd (3), and Tb (4) have been obtained and structurally characterized. Their reaction with 2,2′:6′,2″-terpyridine leads to the formation of 1:1 adducts ([{(2,6-iPr2C6H3-O)2POO}2LnCl(terpy)(H2O)2(CH3OH)], Ln = Eu (5), Gd (6), Tb (7) with exception of Nd, where tris-diisopropylphenylphosphate complex [{(2,6-iPr2C6H3-O)2POO}3Nd) (terpy)(H2O)(CH3OH)] (8) was obtained due to the ligand metathesis. A bright luminescence observed for the Eu and Tb organophosphate complexes is the first example of an application of organophosphate ligands for 4f-ions luminescence sensitization. Photophysical properties of all complexes were analyzed by optical spectroscopy and an energy transfer scheme was discussed. A combination of two types of ligands into the coordination sphere (phosphate and phenanthroline) allows designing the Eu surrounding with very high intrinsic quantum yield QEuEu (0.92) and highly luminescent Ln complexes for both visible and near-infrared (NIR) regions.

Characterization of lanthanum salicylate complex nanoparticles in situ synthesized in silica matrix by a sol–gel process

2004 ◽  
Vol 58 (5) ◽  
pp. 757-761 ◽  
Author(s):  
Xiaofei Yang ◽  
Qizhuang He ◽  
Xianghong He ◽  
Liang Huang
Keyword(s):  
Sol Gel ◽  
Silica Matrix ◽  
Sol Gel Process
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