scholarly journals Factors Affecting the Efficiency of Excited-States Interactions of Complexes between Some Visible Light-Emitting Lanthanide Ions and Cyclophanes Containing Spirobiindanol Phosphonates

2007 ◽  
Vol 2007 ◽  
pp. 1-7 ◽  
Author(s):  
M. S. Attia ◽  
M. M. H. Khalil ◽  
Ayman A. Abdel-Shafi ◽  
G. M. Attia ◽  
Salvatore Failla ◽  
...  
Keyword(s):  
Quantum Yield ◽  
Visible Light ◽  
Excited States ◽  
Photophysical Properties ◽  
Lanthanide Ions ◽  
Luminescence Quantum Yield ◽  
Europium Complexes ◽  
Factors Affecting ◽  
Light Emitting ◽  
Yield Values

The efficiency of excited-states interactions between lanthanide ionsTb3+andEu3+and some new cyclophanes (I, II, and III) has been studied in different media. High luminescence quantum yield values for terbium and europium complexes in DMSO and PMMA were obtained. The photophysical properties of the green and red emissiveTb3+andEu3+complexes have been elucidated, respectively.

Effects of electron-withdrawing groups in imidazole-phenanthroline ligands and their influence on the photophysical properties of EuIII complexes for white light-emitting diodes

2017 ◽  
Vol 41 (18) ◽  
pp. 9826-9839 ◽  
Author(s):  
Boddula Rajamouli ◽  
Rachna Devi ◽  
Abhijeet Mohanty ◽  
Venkata Krishnan ◽  
Sivakumar Vaidyanathan
Keyword(s):  
Thin Film ◽  
Quantum Yield ◽  
White Light ◽  
Light Emitting Diode ◽  
Photophysical Properties ◽  
Red Light ◽  
Europium Complexes ◽  
Light Emitting ◽  
White Light Emitting Diodes ◽  
Phenanthroline Ligands

The red light emitting diode (LED) was fabricated by using europium complexes with InGaN LED (395 nm) and shown digital images, corresponding CIE color coordinates (red region) as well as obtained highest quantum yield of the thin film (78.7%).

scholarly journals Absolute quantum yield measurements of fluorescent proteins using a plasmonic nanocavity

2020 ◽  
Vol 3 (1) ◽  
Author(s):  
Daja Ruhlandt ◽  
Martin Andresen ◽  
Nickels Jensen ◽  
Ingo Gregor ◽  
Stefan Jakobs ◽  
...  
Keyword(s):  
Quantum Yield ◽  
Fluorescent Proteins ◽  
Photophysical Properties ◽  
Dark State ◽  
Absolute Quantum Yield ◽  
Yield Values ◽  
Calibration Free ◽  
Protein Ensembles ◽  
Fluorescent Molecules ◽  
Absolute Quantum

AbstractOne of the key photophysical properties of fluorescent proteins that is most difficult to measure is the quantum yield. It describes how efficiently a fluorophore converts absorbed light into fluorescence. Its measurement using conventional methods become particularly problematic when it is unknown how many of the proposedly fluorescent molecules of a sample are indeed fluorescent (for example due to incomplete maturation, or the presence of photophysical dark states). Here, we use a plasmonic nanocavity-based method to measure absolute quantum yield values of commonly used fluorescent proteins. The method is calibration-free, does not require knowledge about maturation or potential dark states, and works on minute amounts of sample. The insensitivity of the nanocavity-based method to the presence of non-luminescent species allowed us to measure precisely the quantum yield of photo-switchable proteins in their on-state and to analyze the origin of the residual fluorescence of protein ensembles switched to the dark state.

Efficient and long-lifetime full-color light-emitting diodes using high luminescence quantum yield thick-shell quantum dots

Nanoscale ◽  
2017 ◽  
Vol 9 (36) ◽  
pp. 13583-13591 ◽  
Author(s):  
Huaibin Shen ◽  
Qingli Lin ◽  
Weiran Cao ◽  
Chenchen Yang ◽  
Nathan T. Shewmon ◽  
...  
Keyword(s):  
Quantum Dots ◽  
Quantum Yield ◽  
Light Emitting Diodes ◽  
Luminescence Quantum Yield ◽  
Thick Shell ◽  
High Quantum Yield ◽  
Light Emitting ◽  
High Quantum ◽  
Full Color ◽  
Long Lifetime

Peak external quantum efficiencies (EQEs) of 10.2%, 15.4%, and 15.6% were achieved for red, green, and blue QLEDs, respectively, by using high quantum yield thick-shell QDs.

scholarly journals Towards multifunctional lanthanide-based metal–organic frameworks

2015 ◽  
Vol 51 (68) ◽  
pp. 13313-13316 ◽  
Author(s):  
Gerard Tobin ◽  
Steve Comby ◽  
Nianyong Zhu ◽  
Rodolphe Clérac ◽  
Thorfinnur Gunnlaugsson ◽  
...  
Keyword(s):  
Visible Light ◽  
Near Infrared ◽  
Photophysical Properties ◽  
Metal Organic Frameworks ◽  
Structure Type ◽  
Lanthanide Ions ◽  
Light Emitters ◽  
Metal Organic

The structure-type of a Ho(iii)-based MOF can be varied using a range of different lanthanide ions to tune the photophysical properties and produce ligand-sensitised near-infrared and visible light emitters.

scholarly journals A Lanthanide complex for Selective Sensing of Fe (III) Ion

2019 ◽  
Author(s):  
Putri Amanda
Keyword(s):  
Fluorescence Quenching ◽  
Excited States ◽  
Photophysical Properties ◽  
Lanthanide Complex ◽  
Lanthanide Ions ◽  
Absorption Mechanism ◽  
Fluorescence Studies ◽  
Liquid Suspension ◽  
Ft Ir ◽  
Bright Luminescence

Lanthanide complex namely [Ln(Tpy-NH2)2Cl2]Cl where Tpy-NH2 is 4-(p- aminophenyl)-2,2:6,2′′- terpyridine and Ln is Europium dan Dysprosium were synthesized. The ligan was found with reduction of 4-(p-nitrophenyl)-2,2:6,2′′- terpyridine or Tpy-NO2 and photophysical properties such as FT-IR spectra, UV-Vis absorption spectra, and luminescence properties of the complexes in the presence of various metal ions were studied. Here Tpy-NH2 acts as chromophore or light-harvesting photo sensitizing antenna for lanthanide ion in this lanthanide complex. The bright luminescence in complex suggests favorable photo-induced energy transfer happens from the Tpy-NH2 antenna to the lanthanide ions to fill long-lived emissive excited states of lanthanide ions f-f transitions. The luminescence spectral profile of complexes show characteristic sharp multiple emission bands and maximum at 5D0 →7F2 f-f transitions located at 614 nm for complekx Eu and at 4F9/2 →6H15/2 located at 578 nm for complex Dy. The Fluorescence studies revealed that this material showed a highly selective fluorescence quenching response to Fe3+ ions in liquid suspension and its fluorescence quenching response can be explained in terms of the competitive absorption mechanism.

scholarly journals Et3N-DMSO Supported One-pot Synthesis of Highly Fluorescent β-Carboline Linked Benzothiophenones via Sulphur Insertion and Estimation of Their Photophysical Properties

2020 ◽  
Author(s):  
Dharmender Singh ◽  
Vipin Kumar ◽  
Virender Singh
Keyword(s):  
Quantum Yield ◽  
Transition Metal ◽  
Photophysical Properties ◽  
Elemental Sulphur ◽  
One Pot ◽  
Light Emitting ◽  
Metal Free ◽  
One Pot Synthesis ◽  
Synthetic Strategy ◽  
Reaction Proceeds

A robust transition metal-free strategy is presented to access novel β-carboline tethered benzothiophenone derivatives from 1(3)-formyl-β-carbolines using elemental sulphur activated by Et3N/DMSO. This expeditious catalyst-free reaction proceeds through the formation of β-carboline based 2-nitrochalcones followed by incorporation of sulphur to generate the multifunctional β-carboline linked benzothiophenones in good to excellent yields. The synthetic strategy can also be extended towards the synthesis of β-carboline linked benzothiophenes. Moreover, the products as afforded thereof emerged as promising fluorophores and displayed excellent light-emitting properties with quantum yield (ΦF) upto 47%.

Solvent Dependence of Structural Dynamics and Spin-flip Processes in 3,4,5-tri(9H-carbazole-9-yl)benzonitrile (ortho-3CzBN)

2020 ◽  
Author(s):  
Masaki Saigo ◽  
Kiyoshi Miyata ◽  
Hajime Nakanotani ◽  
Chihaya Adachi ◽  
Ken Onda
Keyword(s):  
Dft Calculations ◽  
Excited States ◽  
Structural Changes ◽  
Photophysical Properties ◽  
Delayed Fluorescence ◽  
Time Resolved ◽  
Thermally Activated Delayed Fluorescence ◽  
Thermally Activated ◽  
Solvent Dependence ◽  
Acetonitrile Solutions

We have investigated the solvent-dependence of structural changes along with intersystem crossing of a thermally activated delayed fluorescence (TADF) molecule, 3,4,5-tri(9H-carbazole-9-yl)benzonitrile (o-3CzBN), in toluene, tetrahydrofuran, and acetonitrile solutions using time-resolved infrared (TR-IR) spectroscopy and DFT calculations. We found that the geometries of the S1 and T1 states are very similar in all solvents though the photophysical properties mostly depend on the solvent. In addition, the time-dependent DFT calculations based on these geometries suggested that the thermally activated delayed fluorescence process of o-3CzBN is governed more by the higher-lying excited states than by the structural changes in the excited states.<br>

Probing local photophysical properties in perovskite based light-emitting devices

2019 ◽  
Author(s):  
Miguel Anaya ◽  
Kyle Frohna ◽  
Linsong Cui ◽  
Javad Shamsi ◽  
Sam Stranks
Keyword(s):  
Photophysical Properties ◽  
Light Emitting ◽  
Light Emitting Devices
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