scholarly journals Spectral Behavior and Photophysical Parameters of Dihydrophenanthro[9,10-e][1,2,4]Triazine Derivative Dyes in Sol–gel and Methyl Methacrylate Polymer Matrices

2021 ◽  
Author(s):  
Mahmoud Sakr ◽  
Maram T. H. Abou Kana ◽  
Ahmed H.M. Elwahy ◽  
Samy A. El-Daly A. El-Daly ◽  
El-Zeiny M. Ebeid
Keyword(s):  
Methyl Methacrylate ◽  
Cross Sections ◽  
Electronic Transition ◽  
Photophysical Properties ◽  
Sol Gel ◽  
Emission Spectra ◽  
Molar Absorptivity ◽  
Excited State Lifetime ◽  
Photophysical Parameters ◽  
Photo Stability

Abstract This paper deals the optical and photophysical properties of dihydrophenanthro [9,10-e] [1,2,4] triazine fluorescent derivative dyes doped in Silicate based sol–gel, homo-poly methyl methacrylate (PMMA). Solid hosts effect on the optical and photophysical parameters such as molar absorptivity, cross sections of singlet–singlet electronic absorption and emission spectra, excited state lifetime, quantum yield of fluorescence. Also the dipole moment of electronic transition, the length of attenuation and Oscillator strength of electronic transition from So →S1 have been detected. The dyes with different pumping power were pumped by 3rd harmonic Nd:YAG pulsed laser 8ns pulse duration, with a repetition rate at (10Hz). Good Photo stability of compound 1 and 2 were obtained that was decreased to 49%, 54% and 46%, 40% of the initial ASE of dyes in sol gel and PMMA respectively, after 55000 pumping pulses at (10 mJ/pulse). The dyes in sol-gel show improved Photo stability compared with those in organic polymeric matrices.

Photochemistry Channels of Merocyanine Encapsulated in Sol-Gel Glasses

1994 ◽  
Vol 346 ◽  
Author(s):  
A. M. Mahloudji ◽  
L. B. Meuret ◽  
C. T. Lin
Keyword(s):  
Molecular Form ◽  
Photophysical Properties ◽  
Sol Gel ◽  
Emission Spectra ◽  
Transfer Characteristic ◽  
Optically Transparent ◽  
Quinoid Form ◽  
Gel Glasses ◽  
Processing Techniques ◽  
First Time

ABSTRACTPhotophysical properties of l-Docosyl-4-(4-hydroxystyryl)pyridiniurn bromide (SB), a merocyanine dye in solution and encapsulated in sol-gel derived glass are investigated at 298 and 77 K. In solution, the absorption spectra of SB display an equilibrium between the quinolinium and benzoid forms. The equilibrium can be shifted to either quinolinium or benzoid form under an acidic or basic condition, respectively. The emission spectra of SB, on the other hand, give not only the quinolinium and benzoid forms but also the quinoid form which emits at 500 nm. The existence of excited state quinoid form of SB is also evident in the excitation spectrum while the emission at 500 nm is monitored. Both in solution and in xerogel, the quinoid form of SB is shown to be photochemically unstable as compared to the benzoid form. It is proposed that the photoexcited quinolinium form of SB is a proton dissociative species which transforms readily to become the quinoid form. The results indicate that photochemistry channels of SB are originated from the quinoid form. Moreover, the benzoid form of SB (photochemically stable) exhibits large hyperpolarizability due to its charge-transfer characteristic, and is a desired molecular form for nonlinear optical (NLO) applications. The material processing techniques for stabilizing the benzoid form of SB in optically transparent sol-gel glasses are illustrated for the first time.

Photophysical Properties of Carbazole Derivative DPSPC Doped Composite Glass

2011 ◽  
Vol 239-242 ◽  
pp. 1006-1009
Author(s):  
Yun Long Deng ◽  
Yun Hui Sun ◽  
Du Xia Cao ◽  
Ying Chen ◽  
Zhi Qiang Liu
Keyword(s):  
Fluorescence Quenching ◽  
Methyl Methacrylate ◽  
Photophysical Properties ◽  
Sol Gel ◽  
Organic Dye ◽  
Fluorescence Properties ◽  
Donor Group ◽  
Carbazole Derivative ◽  
Composite Glass ◽  
Gel Glasses

A D-π-D type of organic dye 2,7-di[4-(N,N-diphenylamino)styryl]-9-n-pentyl-9H- carbazole (DPSPC) with diphenylamine as donor group and styrene-carbazole-styrene as conjugation bridge has been synthesized. The photophysical properties of the dye in different solvents and poly methyl methacrylate/organic modified sol-gel glasses are researched. The results indicate that the fluorescence properties of the organic dye in composite glass increase relative to that in solvents and there are no fluorescence quenching in high doped concentration in composite glass matrixes. The dye has higher stability in the composite glass than that in solution.

scholarly journals Fluorescent Silica Hybrid Film-Forming Materials Based on Salicylaldazine

Coatings ◽  
2020 ◽  
Vol 10 (12) ◽  
pp. 1255
Author(s):  
Alina Raditoiu ◽  
Valentin Raditoiu ◽  
Florentina Monica Raduly ◽  
Georgiana Cornelia Ispas ◽  
Violeta Purcar ◽  
...  
Keyword(s):  
Photophysical Properties ◽  
Sol Gel ◽  
Fluorescence Emission ◽  
Emission Spectra ◽  
Hybrid Films ◽  
Fluorescence Emission Spectra ◽  
Network Modifier ◽  
Local Environments ◽  
Film Forming ◽  
Silica Sols

Fluorescent film-forming materials were obtained by embedding salicylaldazine (SAA) in silica hybrids generated by sol–gel processes from different silane precursors in acid catalysis. Tuned local environments for the fluorophore were generated in the hosting network by modifying silica sols with organic groups through the co-condensation of tetraethylortosilicate (TEOS) and different alkoxysilanes hydrolysis products. The photophysical properties of the luminescent hybrid films were studied in direct relationship with structural, textural, and surface properties and based on interactions between SAA species and the silica hosting network. Film-forming materials were studied in order to determine differences in absorption and fluorescence emission due to the environments around the fluorophore. The variations recorded in the fluorescence emission spectra of the hybrid films were related to interactions established between the fluorophore species and their sterically hindered surroundings of the host hybrid silica, where free molecular motions are restricted. The influence of the type and amount of network modifier and of the fluorophore loading on the transparency of the films and fluorescence intensity was also investigated. The study carried out led to the elucidation of the necessary conditions for obtaining luminescent film-forming materials with high luminescence intensity and transparency useful for the design of new light concentrators.

scholarly journals Laser performance and investigation of the optimal density functional and the dependence of the basis sets for (E, E)-2,5-bis (3,4-dimethoxystyryl) pyrazine (BDP) molecule

2021 ◽  
Vol 27 (9) ◽  
Author(s):  
Mahmoud A. S. Sakr ◽  
Sayed A. Abdel Gawad ◽  
Samy A. El-Daly ◽  
Maram T. H. Abou Kana ◽  
El-Zeiny M. Ebeid
Keyword(s):  
Molecular Structure ◽  
Density Functional ◽  
Sol Gel ◽  
Emission Spectra ◽  
Basis Sets ◽  
Functional Theory ◽  
Absorption And Emission ◽  
Absorption And Emission Spectra ◽  
Photophysical Parameters ◽  
Copolymer Matrices

AbstractThis manuscript includes some photophysical parameters and some optical properties such as absorption and emission spectra of the (E, E)-2,5-bis (3,4-dimethoxystyryl) pyrazine (BDP) by applying sol–gel and copolymer matrices. The BDP molecular structure is incorporated in sol–gel matrix and copolymer of methyl methacrylate (MMA) and 2-hydroxyethyl methacrylate (HEMA). In case of sol–gel matrix, the BDP molecular structure has higher quantum yield in addition to photostability maxima. The laser behavior of this molecular structure containing sol–gel matrix is good senior compared to copolymer one via using diode laser (450 nm) as pumping laser of power 160 mW. Also, the fluorescence profile of the BDP molecular structure is sensitized via using cadmium sulfide (CdS) quantum dots (QDs) by applying sol–gel host. The optimized structure of the BDP molecule is obtained via applying B3LYP/6-31G(d) level of theory. The electronic absorption and emission spectra of the BDP molecular structure in ethanol solvent were calculated using time-dependent density functional theory (TDDFT) at CAM-B3LYP/6-31G +  + (d, p) level. The obtained theoretical results were compared to experimental ones.

scholarly journals Laser Performance and Investigation the Optimal Density Functional and the Dependence of the Basis Sets for (E, E)-2, 5-bis (3, 4-Dimethoxystyryl) Pyrazine (BDP) Molecule.

2021 ◽  
Author(s):  
mahmoud sakr ◽  
Sayed Abdel Gawad ◽  
Samy Eldaly ◽  
Maram Abou Kana ◽  
El-Zeiny Ebeid
Keyword(s):  
Molecular Structure ◽  
Density Functional ◽  
Sol Gel ◽  
Emission Spectra ◽  
Cadmium Sulphide ◽  
Basis Sets ◽  
Absorption And Emission ◽  
Absorption And Emission Spectra ◽  
Photophysical Parameters ◽  
Copolymer Matrices

Abstract This manuscript includes some photophysical parameters and some optical properties such as absorption and emission spectra of the (E, E)- 2,5-bis (3,4-dimethoxystyryl) pyrazine (BDP) by applying sol-gel and copolymer matrices. The BDP molecular structure is incorporated in sol-gel matrix and copolymer of methyl methacrylate (MMA) and 2-hydroxy metylmethacrylate (HEMA). In case of sol-gel matrix, the BDP molecular structure has higher quantum yield in addition to photostability maxima. The laser behavior of this molecular structure containing sol-gel matrix is good senior compared to copolymer one via using diode laser (450nm) as pumping laser of power 160 mW. Also, the fluorescence profile of the BDP molecular structure is sensitized via using cadmium sulphide (CdS) quantum dots (QDs) by applying sol-gel host. The optimized structure of the BDP molecule is obtained via applying B3LYP/6-31G(d) level of theory. The electronic absorption and emission spectra of the BDP molecular structure in ethanol solvent, were calculated using time dependent density functional theory (TDDFT) at CAM-B3LYP /6-31G++(d, p) level. The obtained theoretical results were compared to experimental ones.

scholarly journals Upconversion Luminescence of Silica–Calcia Nanoparticles Co-doped with Tm3+ and Yb3+ Ions

Materials ◽  
2021 ◽  
Vol 14 (4) ◽  
pp. 937
Author(s):  
Katarzyna Halubek-Gluchowska ◽  
Damian Szymański ◽  
Thi Ngoc Lam Tran ◽  
Maurizio Ferrari ◽  
Anna Lukowiak
Keyword(s):  
Energy Transfer ◽  
Near Infrared ◽  
Upconversion Luminescence ◽  
Sol Gel ◽  
Emission Spectra ◽  
Transmission Electron ◽  
Characteristic Emission ◽  
Diffraction Patterns ◽  
Size Of Particles ◽  
Average Size

Looking for upconverting biocompatible nanoparticles, we have prepared by the sol–gel method, silica–calcia glass nanopowders doped with different concentration of Tm3+ and Yb3+ ions (Tm3+ from 0.15 mol% up to 0.5 mol% and Yb3+ from 1 mol% up to 4 mol%) and characterized their structure, morphology, and optical properties. X-ray diffraction patterns indicated an amorphous phase of the silica-based glass with partial crystallization of samples with a higher content of lanthanides ions. Transmission electron microscopy images showed that the average size of particles decreased with increasing lanthanides content. The upconversion (UC) emission spectra and fluorescence lifetimes were registered under near infrared excitation (980 nm) at room temperature to study the energy transfer between Yb3+ and Tm3+ at various active ions concentrations. Characteristic emission bands of Tm3+ ions in the range of 350 nm to 850 nm were observed. To understand the mechanism of Yb3+–Tm3+ UC energy transfer in the SiO2–CaO powders, the kinetics of luminescence decays were studied.

Synthesis and Characterization of Y2O3:Eu3+ Film Derived by Sol-Gel Processing

2007 ◽  
Vol 336-338 ◽  
pp. 593-596
Author(s):  
Chun Yang ◽  
Jun Ying Zhang ◽  
Hai Bing Feng ◽  
Wei Chang Hao ◽  
Tian Min Wang
Keyword(s):  
Raw Materials ◽  
Sol Gel ◽  
Emission Spectra ◽  
Luminescent Properties ◽  
Dip Coating ◽  
Organic Additive ◽  
Excitation Spectra ◽  
Excitation Peak ◽  
Close Relationship ◽  
Dip Coating Technique

Y2O3:Eu3+ thin film was synthesized by sol-gel method with inorganic salt raw materials, and the crystal structure and luminescent properties were investigated. By adding organic additive to the sol, a homogeneous film with high luminescent intensity could be obtained by dip-coating technique on the surface of alumina sheet and quartz glass. Structures of the films were studied by XRD and SEM. The excitation spectra of the films showed a wide excitation peak from 200nm to 260nm, and the emission spectra had a strongest emission peak at 611nm which revealed a close relationship with the calcining temperature.

Photophysical Properties of Ruthenium(II) Tris(2,2‘-Bipyridine) and Europium(III) Hexahydrate Salts Assembled into Sol−Gel Materials

2005 ◽  
Vol 17 (22) ◽  
pp. 5512-5520 ◽  
Author(s):  
Wilhelm R. Glomm ◽  
Sondre Volden ◽  
Johan Sjöblom ◽  
Mikael Lindgren
Keyword(s):  
Photophysical Properties ◽  
Sol Gel

Nanocrystalline α-Fe2O3: A Superparamagnetic Material for w-LED Application and Waste Water Treatment

2021 ◽  
Author(s):  
Mahesh Gaidhane ◽  
Deepak Taikar ◽  
Pravin Gaidhane ◽  
Kalpana Nagde
Keyword(s):  
Photocatalytic Activity ◽  
Waste Water Treatment ◽  
Sol Gel ◽  
Average Particle Size ◽  
Emission Spectra ◽  
Broad Emission Band ◽  
Average Particle ◽  
X Ray ◽  
Prepared Material ◽  
Cie Chromaticity

Abstract Nanocrystalline α-Fe2O3 is synthesized by sol-gel technique. The prepared nanomaterial was characterized by X-ray diffraction (XRD), SEM, TEM, Fourier Transform Infrared (FTIR) spectroscopy, Vibrating Sample Magnetometry (VSM) and photoluminescence (PL) techniques. X-ray powder diffraction analysis confirmed the formation of α-Fe2O3. Electron microscopy showed spherical morphologies with an average particle size of 30-40 nm. The magnetic property of the prepared material was studied by VSM at room temperature. VSM study shows superparamagnetic nature of the synthesized nanoparticles. Photoluminescence (PL) emission spectra show intense broad emission band centered at 570 nm with 393 nm excitation indicating its usefulness for w-LED application. The CIE-chromaticity color coordinates of prepared material were calculated. The photocatalytic activity of the α-Fe2O3 nanoparticles was analyzed and the nanopowder exhibited good photocatalytic activity for the removal AO7 from its aqueous solution.

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