Efficient Charge Generation Via Hole Transfer in Dilute Organic Donor-Fullerene Blends

Efficient organic photovoltaics (OPVs) require broadband charge photogeneration with near-unity quantum yield. This can only be achieved by exploiting all pathways that generate charge. Electron transfer from organic donors to acceptors has been well-studied and is considered the primary path to charge photogeneration in OPVs. In contrast, much less is known about the hole transfer pathway. Here we study charge photogeneration in an archetypical system comprising tetraphenyldibenzoperiflanthene: C70 blends using our recently developed multispectral two dimensional electronic spectroscopy (M-2DES), supported by time-dependent density functional theory and fully quantum-mechanical Fermi’s golden rule rate calculations. Our approach identifies in real time two rapid charge transfer pathways that are confirmed through computational analysis. Surprisingly, we find that both electron and hole transfer occur with comparable rates and efficiencies, facilitated by donor-acceptor electronic interactions. Our results highlight the importance of the hole transfer pathway for optimizing the efficiency of OPV devices employing small-molecule heterojunctions.

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Efficient Charge Generation via Hole Transfer in Dilute Organic Donor–Fullerene Blends

The Journal of Physical Chemistry Letters ◽

10.1021/acs.jpclett.0c00058 ◽

2020 ◽

Vol 11 (6) ◽

pp. 2203-2210 ◽

Cited By ~ 5

Author(s):

Yin Song ◽

Alexander Schubert ◽

Xiao Liu ◽

Srijana Bhandari ◽

Stephen R. Forrest ◽

...

Keyword(s):

Charge Generation ◽

Hole Transfer ◽

Efficient Charge ◽

Via Hole

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Efficient charge separation and visible-light response in bilayer HfS2-based van der Waals heterostructures

RSC Advances ◽

10.1039/c8ra03047b ◽

2018 ◽

Vol 8 (34) ◽

pp. 18889-18895 ◽

Cited By ~ 10

Author(s):

Biao Wang ◽

Xukai Luo ◽

Junli Chang ◽

Xiaorui Chen ◽

Hongkuan Yuan ◽

...

Keyword(s):

Charge Separation ◽

Density Functional ◽

Van Der Waals ◽

Light Response ◽

Hybrid Density Functional Theory ◽

Functional Theory ◽

Visible Light Response ◽

Efficient Charge ◽

Hybrid Density Functional ◽

Photocatalytic Applications

In this work, we employ hybrid density functional theory to investigate HfS2-based van der Waals (vdW) heterojunctions for highly efficient photovoltaic and photocatalytic applications.

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Time-Dependent Density-Functional Theory Investigation of the Fluorescence Behavior as a Function of Alkyl Chain Size for the 4-(N,N-Dimethylamino)benzonitrile-like Donor−Acceptor Systems 4-(N,N-Diethylamino)benzonitrile and 4-(N,N-Diisopropylamino)benzonitrile

The Journal of Physical Chemistry B ◽

10.1021/jp0307699 ◽

2004 ◽

Vol 108 (22) ◽

pp. 7132-7141 ◽

Cited By ~ 37

Author(s):

Christine Jödicke Jamorski ◽

Mark E. Casida

Keyword(s):

Density Functional Theory ◽

Density Functional ◽

Alkyl Chain ◽

Time Dependent ◽

Functional Theory ◽

Donor Acceptor ◽

Dependent Density

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Wechselwirkungen in Molekülkristallen, 166 [1, 2]. Polyiod-Moleküle I2C=CI2, (IC)4S, (IC)4NH, (IC)4N-CH3 und HCI3: Strukturbestimmung nach Kristallzüchtung oder durch Dichtefunktionaltheorie-Berechnung / Interaction in Molecular Crystals, 166 [1, 2], Polyiodo Molecules I2C=CI2, (IC)4S, (IC)4 NH, (IC)4N-CH and HCI3: Structure Determination Following Crystallization or by Density Functional Theory Calculation

Zeitschrift für Naturforschung B ◽

10.1515/znb-2001-0104 ◽

2001 ◽

Vol 56 (1) ◽

pp. 13-24 ◽

Cited By ~ 4

Author(s):

Hans Bock ◽

Sven Holl ◽

Volker Krenzel

Keyword(s):

Density Functional Theory ◽

Density Functional ◽

Crystal Packing ◽

Density Functional Theory Calculation ◽

Density Functional Theory Calculations ◽

Structural Data ◽

Basis Sets ◽

Functional Theory ◽

Donor Acceptor ◽

Density Functional Theory Optimization

Abstract The structures of tri-and tetraiodo-substituted carbon compounds are determined either experimentally by X-Ray Structure Analysis or, because crystallization of tetraiodothiophene could not be achieved, approximated by Density Functional Theory optimization of structural data from a donor/acceptor complex. The structures show noteworthy details such as a second polymorph of tetraiodoethene crystallized by sublimation or herringbone crystal packing patterns of tetraiodopyrrole derivatives. All molecular geometries are discussed and compared based on relativistic density functional theory calculations with 6 -31G* basis sets including iodine pseudopotentials. They reproduce even finer structural details due to van der Waals repulsion of the bulky iodo substituents. Natural Bond Orbital (NBO) charge distributions suggest positive partial charges at all iodine centers with the strongest polarization Cδ㊀ → Iδ㊉ in HCI3, which contains well over 97% iodine.

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8-(Pyridin-2-yl)quinolin-7-ol as a Platform for Conjugated Proton Cranes: A DFT Structural Design

Micromachines ◽

10.3390/mi11100901 ◽

2020 ◽

Vol 11 (10) ◽

pp. 901 ◽

Cited By ~ 1

Author(s):

Anton Georgiev ◽

Liudmil Antonov

Keyword(s):

Excited State ◽

Structural Design ◽

Density Functional ◽

Intramolecular Proton Transfer ◽

State Density ◽

Strong Electron ◽

Functional Theory ◽

Substituted Pyridines ◽

Donor Acceptor ◽

Enol Tautomer

Theoretical design of conjugated proton cranes, based on 7-hydroxyquinoline as a tautomeric sub-unit, has been attempted by using ground and excited state density functional theory (DFT) calculations in various environments. The proton crane action request existence of a single enol tautomer in ground state, which under excitation goes to the excited keto tautomer through a series of consecutive excited-state intramolecular proton transfer (ESIPT) steps with the participation of the crane sub-unit. A series of substituted pyridines was used as crane sub-units and the corresponding donor-acceptor interactions were evaluated. The results suggest that the introduction of strong electron donor substituents in the pyridine ring creates optimal conditions for 8-(pyridin-2-yl)quinolin-7-ols to act as proton cranes.

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Molecular modeling and simulation of some efficient charge transfer materials using density functional theory

Materials Today Communications ◽

10.1016/j.mtcomm.2019.100788 ◽

2020 ◽

Vol 22 ◽

pp. 100788

Author(s):

Shamoon Ahmad Siddiqui ◽

Mohammad Margub Abdullah

Keyword(s):

Density Functional Theory ◽

Charge Transfer ◽

Molecular Modeling ◽

Modeling And Simulation ◽

Density Functional ◽

Functional Theory ◽

Efficient Charge ◽

Charge Transfer Materials

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Potential thermally activated delayed fluorescence properties of a series of 2,3-dicyanopyrazine based compounds

Physical Sciences Reviews ◽

10.1515/psr-2017-0197 ◽

2018 ◽

Vol 3 (7) ◽

Author(s):

Ayşegül Gümüş ◽

Selçuk Gümüş

Keyword(s):

Density Functional Theory ◽

Density Functional ◽

Delayed Fluorescence ◽

Basis Sets ◽

Functional Theory ◽

Thermally Activated Delayed Fluorescence ◽

Thermally Activated ◽

Structural And Electronic Properties ◽

Donor Acceptor ◽

Almost All

Abstract 2,3-Dicyanopyrazine based acceptor was combined with a series of well studied donors to obtain donor-acceptor type potential thermally activated delayed fluorescence emitters. Their structural and electronic properties were computed theoretically at the level of density functional theory and time dependent density functional theory with the application of two different hybrid functionals and various basis sets. Almost all of the designed structures were computed to have the potential of being TADF compounds since they possess very narrow singlet-triplet gaps. Indeed, acridine-pyrazine (9) derivative was calculated to be the best candidate for the purpose among them.

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Fluorene-Based Donor-Acceptor Copolymers Containing Functionalized Benzotriazole Units: Tunable Emission and their Electrical Properties

Polymers ◽

10.3390/polym12020256 ◽

2020 ◽

Vol 12 (2) ◽

pp. 256 ◽

Cited By ~ 1

Author(s):

Iván Torres-Moya ◽

Rebeca Vázquez-Guilló ◽

Sara Fernández-Palacios ◽

José Ramón Carrillo ◽

Ángel Díaz-Ortiz ◽

...

Keyword(s):

Density Functional ◽

Field Effect Transistors ◽

Photophysical Properties ◽

Suzuki Reaction ◽

Organic Field Effect Transistors ◽

Functional Theory ◽

Organic Optoelectronics ◽

Donor Acceptor ◽

Chain Lengths ◽

Tunable Emission

Monomers 4,7-dibromo-2H-benzo[d]1,2,3-triazole (m1) and 4,7-(bis(4-bromophenyl)ethynyl)-2H-benzo[d]1,2,3-triazole (m2) have been synthesized in good yields using different procedures. Monomers m1 and m2 have been employed for building new copolymers of fluorene derivatives by a Suzuki reaction under microwave irradiation using the same conditions. In each case different chain lengths have been achieved, while m1 gives rise to polymers for m2 oligomers have been obtained (with a number of monomer units lower than 7). Special interest has been paid to their photophysical properties due to excited state properties of these D-A units alternates, which have been investigated by density functional theory (DFT) calculations using two methods: (i) An oligomer approach and (ii) by periodic boundary conditions (PBC). It is highly remarkable the tunability of the photophysical properties as a function of the different monomer functionalization derived from 2H-benzo[d]1,2,3-triazole units. In fact, a strong modulation of the absorption and emission properties have been found by functionalizing the nitrogen N-2 of the benzotriazole units or by elongation of the π-conjugated core with the introduction of alkynylphenyl groups. Furthermore, the charge transport properties of these newly synthesized macromolecules have been approached by their implementation in organic field-effect transistors (OFETs) in order to assess their potential as active materials in organic optoelectronics.

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