Conjugated anthracene dendrimers with monomer-like fluorescence

Börjesson, Karl; Gilbert, Mélina; Dzebo, Damir; Albinsson, Bo; Moth‐Poulsen, Kasper

doi:10.1039/c4ra02341b

Cited by 7 publications

(10 citation statements)

References 38 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…9-Bromo-10-phenylanthracene was synthesized according to the literature. 52 Preparation of 4-(10-phenylanthracene-9-yl)pyridine, 3. The title compound was synthesized as follows: 330 mg (0.99 mmol) of 9-bromo-10-phenylanthracene was added to a reaction vessel together with 201 mg (0.98 mmol) of 4-pyridine boronic acid pinacole ester and 27 mg (0.02 mmol, 2 mol%) of Pd(PPh 3 ) 4 .…”

Section: Synthesismentioning

confidence: 99%

Photophysical characterization of the 9,10-disubstituted anthracene chromophore and its applications in triplet–triplet annihilation photon upconversion

et al. 2015

Self Cite

View full text Add to dashboard Cite

show abstract

Section: Synthesismentioning

confidence: 99%

Photophysical characterization of the 9,10-disubstituted anthracene chromophore and its applications in triplet–triplet annihilation photon upconversion

et al. 2015

Self Cite

View full text Add to dashboard Cite

show abstract

“…Here we demonstrate that by effectively extending the triplet lifetime of the ruthenium complex by coordination of the anthracene ligands, the upconversion quantum yield is increased threefold to 4.5% with complex RuOEP(CO)2. We have previously studied the properties of DPA based dendrimers and oligomers 45,62 and shown that intra-molecular TTA is possible in such structures. Combined with the current study, where efficient intra-molecular TET is achieved, we are en route to developing fully functioning, well defined, supramolecular TTA upconversion systems, with broad implications spanning solar energy harvesting devices to bioimaging and drug targeting.…”

Section: Resultsmentioning

confidence: 99%

“…Ligand design is based on our previous work with 9,10-diphenylanthracene (DPA) based ligands and dendrimeric structures. 25,45 Fig. 1 shows the structures of the ligands: ligand 1 has a metapyridine substitution, ligands 2-5 have para-pyridine substitutions with increasing bridge lengths and dendrimeric ligands 6 and 7 have an increasing number of DPA monomer units.…”

Section: Ligand Design and Synthesismentioning

confidence: 99%

“…25 The dendrimer ligands were synthesized by repeating a sequence of three high yielding and simple reactions; bromination followed by borylation followed by a Suzuki-coupling, similar to our previously established route for DPA dendrons and dendrimers. 45 The synthetic route is illustrated in Fig. S1 and described in more detail in the ESI.…”

Section: Ligand Design and Synthesismentioning

confidence: 99%

See 1 more Smart Citation

Singlet and triplet energy transfer dynamics in self-assembled axial porphyrin–anthracene complexes: towards supra-molecular structures for photon upconversion

Gray

Küçüköz

Edhborg

et al. 2018

Phys. Chem. Chem. Phys.

Self Cite

View full text Add to dashboard Cite

Energy and electron transfer reactions are central to many different processes and research fields, from photosynthesis and solar energy harvesting to biological and medical applications. Herein we report a comprehensive study of the singlet and triplet energy transfer dynamics in porphyrin-anthracene coordination complexes. Seven newly synthesized pyridine functionalized anthracene ligands, five with various bridge lengths and two dendrimer structures containing three and seven anthracene units, were prepared. We found that triplet energy transfer from ruthenium octaethylporphyrin to an axially coordinated anthracene is possible, and is in some cases followed by back triplet energy transfer to the porphyrin. The triplet energy transfer follows an exponential distance dependence with an attenuation factor, β, of 0.64 Å. Further, singlet energy transfer from anthracene to the ruthenium porphyrin appears to follow a R Förster distance dependence. Porphyrin-anthracene complexes are also used as triplet sensitizers for triplet-triplet annihilation (TTA) based photon upconversion, demonstrating their potential for photophysical and photochemical applications. The triplet lifetime of the complex is extended by the anthracene ligands, resulting in a threefold increase in the upconversion efficiency, Φ to 4.5%, compared to the corresponding ruthenium porphyrin-pyridine complex. Based on the results herein we discuss the future design of supra-molecular structures for TTA upconversion.

show abstract

“…(3) Efficiency limits and maximal energy storage densities in molecular solar thermal materials is discussed (4,5) and new systems are being developed. (6)(7)(8) An overview of our research efforts to harness solar energy by developing a) efficient MOST and b) triplet-triplet annihilation photon upconversion systems (TTA-UC) will be presented. (1-9) Our work is both focused on development of new materials (1,(6)(7)(8) and the demonstration of their function in devices.…”

Section: Figure 1 Energy Diagram Explaining the Enthalpy Of Energy Smentioning

confidence: 99%

Photon up-conversion and molecular solar thermal energy storage: New materials and devices

Börjesson

Lennartsson²,

Gray

et al. 2014

2014 IEEE Photonics Conference

Self Cite

View full text Add to dashboard Cite

In a future society with limited access to fossil fuels, technologies for efficient on demand delivery of renewable energy are highly desirable. In this regard, methods that allow for solar energy storage and on demand solar driven energy generation are particularly relevant since the sun is the most abundant energy source. The talk will focus on the possibility to harness and store solar energy in chemical bonds by the use of photochromic molecules (molecular solar thermal energy storage, MOST). Photochromic molecules are capable of reversible isomerisation between two metastable isomers when exposed to light. These two isomers have distinct chemical and physical properties, such as HOMO and LUMO energy levels. In molecular solar thermal energy storage, photochromic molecules with a large difference in energy between the two isomers is used and the energy difference between these two isomers equals to the molar energy storage capacity of the system (Figure 1). Molecular solar thermal (MOST) is a concept for long term storage of solar energy in molecules and release of the energy as heat with full regeneration of the initial materials. The process is inherently closed cycle and emission free. Critical design parameters of the photochromic materials will in the talk be discussed and includes:1) The effect of the HOMO-LUMO gap of the low and high energy isomers on the solar harnessing capability and efficiency.2) The effect of the thermal energy barrier on the energy storage density.3) The effect of the thermal energy barrier on the storage lifetime. 4) The use of catalytic back conversion and energy extraction. 5) The use of triplet-triplet annihilation photon upconversion (TTA-UC) to enhance efficiency of energy conversion. Figure 1. Energy diagram explaining the enthalpy of energy storage (H storage ) and the activation energy of backisomerization (E a ) between the low (parent) and high (photoisomer) energy isomers.The Shockley and Queisser type limits set solar power conversion efficiency limitation on all single bandgap solar harvesting devices. A generic approach to circumvent the Shockley and Queisser limit is by photon upconversion. By transforming two low energy photons to one high energy photon, the 445 WD2.4 (Invited) 11:30 AM -11:45 AM 978-1-4577-1504-4/14/$26.00 ©2014 IEEE

show abstract

Conjugated anthracene dendrimers with monomer-like fluorescence

Abstract: A series of highly fluorescent conjugated anthracene dendrimers having monomeric emission profile, but still exhibiting fast exciton depolarisation, are here presented.

Cited by 7 publications

References 38 publications

Photophysical characterization of the 9,10-disubstituted anthracene chromophore and its applications in triplet–triplet annihilation photon upconversion

Photophysical characterization of the 9,10-disubstituted anthracene chromophore and its applications in triplet–triplet annihilation photon upconversion

Singlet and triplet energy transfer dynamics in self-assembled axial porphyrin–anthracene complexes: towards supra-molecular structures for photon upconversion

Photon up-conversion and molecular solar thermal energy storage: New materials and devices

Contact Info

Product

Resources

About