Dr Andrew Danos' Outputs (9)

Not the Sum of their Parts: Understanding Multi-Donor Interactions in Symmetric and Asymmetric TADF Emitters (2021)
Journal Article
Danos, A., Gudeika, D., Kukhta, N., Lygaitis, R., Colella, M., Higginbotham, H., Bismillah, A. N., McGonigal, P. R., Grazulevicius, J. V., & Monkman, A. P. (2022). Not the Sum of their Parts: Understanding Multi-Donor Interactions in Symmetric and Asymmetric TADF Emitters. Journal of Materials Chemistry C Materials for optical and electronic devices, 10(12), 4737-4747. https://doi.org/10.1039/d1tc04171a

A pair of thermally activated delayed fluorescence (TADF) emitters with symmetric and asymmetric D-A-D structure are investigated. Despite displaying near-identical photoluminescence spectrum and quantum yields, the symmetric material possesses signi... Read More about Not the Sum of their Parts: Understanding Multi-Donor Interactions in Symmetric and Asymmetric TADF Emitters.

Effects of asymmetric acceptor and donor positioning in deep blue pyridyl-sulfonyl based TADF emitters (2021)
Journal Article
Haykir, G., Aydemir, M., Danos, A., Gumus, S., Hizal, G., Monkman, A. P., & Turksoy, F. (2021). Effects of asymmetric acceptor and donor positioning in deep blue pyridyl-sulfonyl based TADF emitters. Dyes and Pigments, 194, Article 109579. https://doi.org/10.1016/j.dyepig.2021.109579

In this work, we report synthesis and photophysical properties of deep-blue emitting donor-acceptor (D-A) and donor-acceptor-donor (D-A-D) thermally activated delayed fluorescence (TADF) molecules, where the molecules designed using carbazole as a do... Read More about Effects of asymmetric acceptor and donor positioning in deep blue pyridyl-sulfonyl based TADF emitters.

Silylethynyl Substitution for Preventing Aggregate Formation in Perylene Diimides (2021)
Journal Article
Aksoy, E., Danos, A., Li, C., Monkman, A. P., & Varlikli, C. (2021). Silylethynyl Substitution for Preventing Aggregate Formation in Perylene Diimides. Journal of Physical Chemistry C, 125(23), 13041-13049. https://doi.org/10.1021/acs.jpcc.1c03131

Ethynylene-bridged perylene diimides (PDIs) with different sized silane groups have been synthesized as a steric blocking group to prevent the formation of non-radiative trap sites, for example, strong H-aggregates and other dimers or excimers. Excit... Read More about Silylethynyl Substitution for Preventing Aggregate Formation in Perylene Diimides.

Vibrational Damping Reveals Vibronic Coupling in Thermally Activated Delayed Fluorescence Materials (2021)
Journal Article
Hempe, M., Kukhta, N. A., Danos, A., Fox, M. A., Batsanov, A. S., Monkman, A. P., & Bryce, M. R. (2021). Vibrational Damping Reveals Vibronic Coupling in Thermally Activated Delayed Fluorescence Materials. Chemistry of Materials, 33(9), 3066-3080. https://doi.org/10.1021/acs.chemmater.0c03783

We investigate a series of D–A molecules consisting of spiro[acridan-9,9′-fluorene] as the donor and 2-phenylenepyrimidine as the acceptor. In two of the materials, a spiro center effectively electronically isolates the D unit from (consequently) opt... Read More about Vibrational Damping Reveals Vibronic Coupling in Thermally Activated Delayed Fluorescence Materials.

Are the Rates of Dexter Transfer in TADF Hyperfluorescence Systems Optically Accessible? (2021)
Journal Article
Haase, N., Danos, A., Pflumm, C., Stachelek, P., Brütting, W., & Monkman, A. P. (2021). Are the Rates of Dexter Transfer in TADF Hyperfluorescence Systems Optically Accessible?. Materials Horizons, 8(6), 1805-1815. https://doi.org/10.1039/d0mh01666g

Seemingly not, but for unexpected reasons. Combining the triplet harvesting properties of TADF materials with the fast emission rates and colour purity of fluorescent emitters is attractive for developing high performance OLEDs. In this “hyperfluores... Read More about Are the Rates of Dexter Transfer in TADF Hyperfluorescence Systems Optically Accessible?.

Difluorodithieno[3,2-a:2′,3′-c]phenazine as a strong acceptor for materials displaying thermally activated delayed fluorescence or room temperature phosphorescence (2021)
Journal Article
Cardeynaels, T., Paredis, S., Danos, A., Harrison, A., Deckers, J., Brebels, S., Lutsen, L., Vanderzande, D., Monkman, A. P., Champagne, B., & Maes, W. (2021). Difluorodithieno[3,2-a:2′,3′-c]phenazine as a strong acceptor for materials displaying thermally activated delayed fluorescence or room temperature phosphorescence. Dyes and Pigments, 190, https://doi.org/10.1016/j.dyepig.2021.109301

A novel strong electron-acceptor unit, 9,10-difluorodithieno[3,2-a:2′,3′-c]phenazine (DTPz), is synthesized and applied in the design of two donor-acceptor type emitters displaying long-lived delayed emission. Using either 9,9-dimethyl-9,10-dihydroac... Read More about Difluorodithieno[3,2-a:2′,3′-c]phenazine as a strong acceptor for materials displaying thermally activated delayed fluorescence or room temperature phosphorescence.

Conformational Dependence of Triplet Energies in Rotationally Hindered N‐ and S‐Heterocyclic Dimers: New Design and Measurement Rules for High Triplet Energy OLED Host Materials (2021)
Journal Article
Wright, I. A., Danos, A., Montanaro, S., Batsanov, A. S., Monkman, A. P., & Bryce, M. R. (2021). Conformational Dependence of Triplet Energies in Rotationally Hindered N‐ and S‐Heterocyclic Dimers: New Design and Measurement Rules for High Triplet Energy OLED Host Materials. Chemistry - A European Journal, 27(21), 6545-6556. https://doi.org/10.1002/chem.202100036

A series of four heterocyclic dimers has been synthesized, with twisted geometries imposed across the central linking bond by ortho‐alkoxy chains. These include two isomeric bicarbazoles, a bis(dibenzothiophene‐S,S‐dioxide) and a bis(thioxanthene‐S,S... Read More about Conformational Dependence of Triplet Energies in Rotationally Hindered N‐ and S‐Heterocyclic Dimers: New Design and Measurement Rules for High Triplet Energy OLED Host Materials.

Hot Vibrational States in a High-Performance Multiple Resonance Emitter and the Effect of Excimer Quenching on Organic Light-Emitting Diodes (2021)
Journal Article
Stavrou, K., Danos, A., Hama, T., Hatakeyama, T., & Monkman, A. (2021). Hot Vibrational States in a High-Performance Multiple Resonance Emitter and the Effect of Excimer Quenching on Organic Light-Emitting Diodes. ACS Applied Materials and Interfaces, 13(7), 8643-8655. https://doi.org/10.1021/acsami.0c20619

The photophysics of multiple resonance thermally activated delayed fluorescence molecule ν-DABNA is described. We show coupling of a 285 cm–1 stretching/scissoring vibrational mode of peripheral phenyl rings to the S1 state, which dictates the ultima... Read More about Hot Vibrational States in a High-Performance Multiple Resonance Emitter and the Effect of Excimer Quenching on Organic Light-Emitting Diodes.

The Critical Role of nπ* States in the Photophysics and Thermally Activated Delayed Fluorescence of Spiro Acridine-Anthracenone (2021)
Journal Article
Gomes Franca, L., Long, Y., Li, C., Danos, A., & Monkman, A. (2021). The Critical Role of nπ* States in the Photophysics and Thermally Activated Delayed Fluorescence of Spiro Acridine-Anthracenone. Journal of Physical Chemistry Letters, 12(5), 1490-1500. https://doi.org/10.1021/acs.jpclett.0c03314

The molecular photophysics and thermally activated delayed fluorescence (TADF) in spiro compounds are distinct because of the rigid orthogonal C–C bridging bond between donor and acceptor. The photophysics is found to be highly complex, with unpreced... Read More about The Critical Role of nπ* States in the Photophysics and Thermally Activated Delayed Fluorescence of Spiro Acridine-Anthracenone.