Diphenylanthracene Dimers for Triplet–Triplet Annihilation Photon Upconversion: Mechanistic Insights for Intramolecular Pathways and the Importance of Molecular Geometry
Artikel i vetenskaplig tidskrift, 2021

Novel approaches to modify the spectral output of the sun have seen a surge in interest recently, with triplet–triplet annihilation driven photon upconversion (TTA-UC) gaining widespread recognition due to its ability to function under low-intensity, noncoherent light. Herein, four diphenylanthracene (DPA) dimers are investigated to explore how the structure of these dimers affects upconversion efficiency. Also, the mechanism responsible for intramolecular upconversion is elucidated. In particular, two models are compared using steady-state and time-resolved simulations of the TTA-UC emission intensities and kinetics. All dimers perform TTA-UC efficiently in the presence of the sensitizer platinum octaethylporphyrin. The meta-coupled dimer 1,3-DPA2 performs best yielding a 21.2% upconversion quantum yield (out of a 50% maximum), which is close to that of the reference monomer DPA (24.0%). Its superior performance compared to the other dimers is primarily ascribed to the longer triplet lifetime of this dimer (4.7 ms), thus reinforcing the importance of this parameter. Comparisons between simulations and experiments reveal that the double-sensitization mechanism is part of the mechanism of intramolecular upconversion and that this additional pathway could be of great significance under specific conditions. The results from this study can thus act as a guide not only in terms of annihilator design but also for the design of future solid-state systems where intramolecular exciton migration is anticipated to play a major role.

fluorescence

intramolecular TTA

photon upconversion

solar energy conversion

Författare

Axel Olesund

Chalmers, Kemi och kemiteknik, Kemi och biokemi, Fysikalisk kemi

Victor Gray

Chalmers, Kemi och kemiteknik, Kemi och biokemi

Jerker Mårtensson

Chalmers, Kemi och kemiteknik, Kemi och biokemi

Bo Albinsson

Chalmers, Kemi och kemiteknik, Kemi och biokemi

Journal of the American Chemical Society

0002-7863 (ISSN) 1520-5126 (eISSN)

Vol. 143 15 5745-5754

Uppkonvertering av fotonenergier i fastfas: Nya material för att bryta Shockley-Queisser gränsen

Energimyndigheten, 2019-01-01 -- 2023-12-31.

Drivkrafter

Hållbar utveckling

Styrkeområden

Nanovetenskap och nanoteknik (SO 2010-2017, EI 2018-)

Ämneskategorier

Fysikalisk kemi

Kemi

DOI

10.1021/jacs.1c00331

PubMed

33835789

Mer information

Senast uppdaterat

2021-05-18