Competitive Triplet Formation and Recombination in Crystalline Films of Perylenediimide Derivatives: Implications for Singlet Fission

2020 ◽  
Vol 124 (21) ◽  
pp. 11574-11585 ◽  
Author(s):  
Saghar Masoomi-Godarzi ◽  
Christopher R. Hall ◽  
Bolong Zhang ◽  
Mark A. Gregory ◽  
Jonathan M. White ◽  
...  
Keyword(s):  
Singlet Fission ◽  
Crystalline Films ◽  
Triplet Formation

Morphology independent triplet formation in pentalene films: Singlet fission as the triplet formation mechanism

2019 ◽  
Vol 151 (12) ◽  
pp. 124701 ◽  
Author(s):  
Long Wang ◽  
Yishi Wu ◽  
Yanping Liu ◽  
Lanfen Wang ◽  
Jiannian Yao ◽  
...  
Keyword(s):  
Formation Mechanism ◽  
Singlet Fission ◽  
Triplet Formation

scholarly journals Unveiling the concentration dependent direct triplet formation via singlet fission in a tetracene derivative

2019 ◽  
Vol 205 ◽  
pp. 09031
Author(s):  
Nikolaus Wollscheid ◽  
Nicolo Alagna ◽  
J. Luis Perez Lustres ◽  
Tiago Buckup ◽  
Sebastian Hahn ◽  
...  
Keyword(s):  
Thin Films ◽  
Underlying Mechanism ◽  
Intersystem Crossing ◽  
Singlet Fission ◽  
Concentrated Solutions ◽  
Triplet Formation

Singlet fission is slowed down on diffusional timescales in highly concentrated solutions compared to thin films for a tetracene-like molecule. The underlying mechanism suggests competing intersystem crossing and singlet fission, where in the latter singlets are converted directly to triplets without an intermediate excimer state.

scholarly journals Using Structurally Well-Defined Norbornyl-Bridged Acene Dimers to Map a Mechanistic Landscape for Correlated Triplet Formation in Singlet Fission

2019 ◽  
Vol 141 (14) ◽  
pp. 5961-5971 ◽  
Author(s):  
Alexander T. Gilligan ◽  
Ethan G. Miller ◽  
Tarek Sammakia ◽  
Niels H. Damrauer
Keyword(s):  
Singlet Fission ◽  
Triplet Formation

scholarly journals Ultrafast spectroscopy reveals singlet fission, ionization and excimer formation in perylene film

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Wenjun Ni ◽  
Licheng Sun ◽  
Gagik G. Gurzadyan
Keyword(s):  
Radical Cation ◽  
Transient Absorption ◽  
Photovoltaic Devices ◽  
Singlet Fission ◽  
Time Resolved ◽  
Singlet Exciton ◽  
Femtosecond Transient Absorption ◽  
Photovoltaic Applications ◽  
Singlet Exciton Fission ◽  
Triplet Formation

AbstractSinglet exciton fission (SF) is a spin-allowed process whereby two triplet excitons are created from one singlet exciton. This phenomenon can offset UV photon energy losses and enhance the overall efficiency in photovoltaic devices. For this purpose, it requires photostable commercially available SF materials. Excited state dynamics in pure perylene film, ease of commercial production, is studied by time-resolved fluorescence and femtosecond transient absorption techniques under different photoexcitation energies. In film, polycrystalline regions contain perylene in H-type aggregate form. SF takes place from higher excited states of these aggregates in ultrafast time scale < 30 fs, reaching a triplet formation quantum yield of 108%. Moreover, at λex = 450 nm singlet fission was detected as a result of two-quantum absorption. Other competing relaxation channels are excimer (1 ps) and dimer radical cation formation (< 30 fs). Excimer radiatively relaxes within 19 ns and radical cation recombines in 3.2 ns. Besides, exciton self-trapping by crystal lattice distortions occurs within hundreds of picosecond. Our results highlight potential of simple-fabricated perylene films with similar properties as high-cost single crystal in SF based photovoltaic applications.

Designs of Singlet Fission Chromophores with a Diazadiaborine Framework

2020 ◽  
Author(s):  
Ekadashi Pradhan ◽  
Jordan N. Bentley ◽  
Christopher B. Caputo ◽  
Tao Zeng
Keyword(s):  
Computational Chemistry ◽  
Singlet Fission ◽  
Diradical Character

This is a computational chemistry study in designing singlet fission chromophores based on a diazadiborine framework. Substitutions and additions are proposed to enhance diradical character of the diazadiborine so that the designed molecules satisfy the two energy criteria for singlet fission. Synthesizability of the designed molecules is discussed.

Solvent-Free Powder Synthesis and MOF-CVD Thin Films of the Mesoporous Metal-Organic Framework MAF-6

2019 ◽  
Author(s):  
Timothée Stassin ◽  
Ivo Stassen ◽  
Joao Marreiros ◽  
Alexander John Cruz ◽  
Rhea Verbeke ◽  
...  
Keyword(s):  
Vapor Phase ◽  
Metal Organic Framework ◽  
Chemical Vapor ◽  
Uptake Capacity ◽  
Powder Synthesis ◽  
Crystalline Films ◽  
Metal Organic ◽  
Mesoporous Metal ◽  
First Time ◽  
Organic Framework

A simple solvent- and catalyst-free method is presented for the synthesis of the mesoporous metal-organic framework (MOF) MAF-6 (RHO-Zn(eIm)2) based on the reaction of ZnO with 2-ethylimidazole vapor at temperatures ≤ 100 °C. By translating this method to a chemical vapor deposition (CVD) protocol, mesoporous crystalline films could be deposited for the first time entirely from the vapor phase. A combination of PALS and Kr physisorption measurements confirmed the porosity of these MOF-CVD films and the size of the MAF-6 supercages (diam. ~2 nm), in close agreement with powder data and calculations. MAF-6 powders and films were further characterized by XRD, TGA, SEM, FTIR, PDF and EXAFS. The exceptional uptake capacity of the mesoporous MAF-6 in comparison to the microporous ZIF-8 is demonstrated by vapor-phase loading of a molecule larger than the ZIF-8 windows.

Singlet Fission: Chromophores for Exciton Downconversion

2019 ◽  
Author(s):  
Alexandr Zaykov ◽  
Josef Michl ◽  
Zdeněk Havlas ◽  
Eric Buchanan ◽  
Milena Jovanović
Keyword(s):  
Singlet Fission

scholarly journals Magnetic dipolar interaction between correlated triplets created by singlet fission in tetracene crystals

2015 ◽  
Vol 6 (1) ◽  
Author(s):  
Rui Wang ◽  
Chunfeng Zhang ◽  
Bo Zhang ◽  
Yunlong Liu ◽  
Xiaoyong Wang ◽  
...  
Keyword(s):  
Dipolar Interaction ◽  
Singlet Fission ◽  
Magnetic Dipolar Interaction
Sign in / Sign up

Export Citation Format

Share Document