Exciton Diffusion to Low Energy Sites of the Acceptor Drives Charge Photogeneration in D18:Y6 Solar Cells DOI Creative Commons
Thomas Sayner, Arvydas Ruseckas, Jonathon R. Harwell

и другие.

The Journal of Physical Chemistry C, Год журнала: 2024, Номер 128(45), С. 19319 - 19328

Опубликована: Окт. 31, 2024

We have investigated charge generation pathways in efficient organic photovoltaic blends of the polymer donor D18 and small-molecule acceptor Y6 using transient absorption time-resolved fluorescence spectroscopies. find that energy transfer from to outcompetes electron is followed by exciton diffusion regions disordered phase aggregates before hole D18. Aggregation molecules increases their ionization ∼0.3 eV provides a driving force for excitons spontaneously generated pairs observed ultrafast depolarization ground-state bleaching <200 fs, which indicates delocalization primary aggregates. This can explain spontaneous neat films Y6-rich blends. Our results show subtle aggregation control low-energy absorber be used balancing photocurrent with low voltage loss

Язык: Английский

New Avenues for Organic Solar Cells Using Intrinsically Charge-Generating Materials DOI Creative Commons
Paul Hume, Michael B. Price, Justin M. Hodgkiss

и другие.

JACS Au, Год журнала: 2024, Номер 4(4), С. 1295 - 1302

Опубликована: Март 18, 2024

The molecular electron acceptor material Y6 has been a key part of the most recent surge in organic solar cell sunlight-to-electricity power conversion efficiency, which is now approaching 20%. Numerous studies have sought to understand fundamental photophysical reasons for exceptional performance and its growing family structural derivatives. Though significant uncertainty about several details remains, many concluded that initially photogenerated excited states rapidly convert into electron–hole charge pairs neat material. These are characterized by location hole on different molecules, contrast Frenkel excitons dominate behavior semiconductor materials. Here, we summarize current state knowledge regarding photophysics observations led it. We then link this understanding other advances, such as role quadrupolar fields donor–acceptor blends, importance interactions organization providing basis Y6′s properties. Finally, turn our attention ways making use new Y6, suggest doping, crystal structure tuning, electric field engineering promising avenues future exploration.

Язык: Английский

Процитировано

9

Review on the DFT computation of bulk heterojunction and dye-sensitized organic solar cell properties DOI
Nathália M. P. Rosa, Itamar Borges

Journal of Molecular Modeling, Год журнала: 2025, Номер 31(3)

Опубликована: Фев. 13, 2025

Язык: Английский

Процитировано

1

Size Inhomogeneity Facilitates Exciton Dissociation in Carbon Dots DOI
Jiawen Fang,

Zengbo Fan,

Qinxiang Huang

и другие.

Nano Letters, Год журнала: 2025, Номер 25(6), С. 2554 - 2560

Опубликована: Янв. 31, 2025

Organic carbon dots (CDs) exhibit tunable electronic structures and exceptional optical properties, supporting both exciton- charge-driven applications. However, the mechanisms underlying this dual functionality are poorly understood. This study establishes role of size inhomogeneity in exciton dissociation for first time. Two distinct CD types were identified, each class with a deviation. Intradot relaxation within same type CDs composes fast (∼1 ps) slow (∼tens picoseconds) component among size-deviated subpopulations. Interdot transfer between two occurs time scale 4.4 ps but is evident only when higher-energy states excited. It also facilitates dissociation, generating nearly free carriers, confirmed by EPR spectra (g-value = 2.005). These findings highlight critical energy level alignment selective excitation mediating providing key insights optimizing light emission conversion

Язык: Английский

Процитировано

0

Towards high-throughput exciton diffusion rate prediction in molecular organic semiconductors DOI
Geoffrey R. Weal, Joshua J. Sutton, Chayanit Wechwithayakhlung

и другие.

Journal of Materials Chemistry C, Год журнала: 2024, Номер 12(24), С. 8747 - 8758

Опубликована: Янв. 1, 2024

Accurate property prediction is paramount to high-throughput screening of organic photovoltaics. Here, the accuracy predicting exciton diffusion computationally examined, and several simplifications towards are explored.

Язык: Английский

Процитировано

2

How Rigid Are Anthranilamide Molecular Electrets? DOI Creative Commons
Omar O’Mari, Moon Young Yang, William A. Goddard

и другие.

The Journal of Physical Chemistry B, Год журнала: 2024, Номер unknown

Опубликована: Ноя. 20, 2024

As important as molecular electrets are for electronic materials and devices, conformational fluctuations strongly impact their macrodipoles intrinsic properties. Herein, we employ dynamics (MD) simulations with the polarizable charge equilibrium (PQEq) method to investigate persistence length (LP) of composed anthranilamide (Aa) residues. The PQEq-MD dissipates accepted static notions about Aa macromolecules, LP represents shortest rigid segments. classical model a single value does not describe these oligomers. Introducing multiple values same macromolecule follows observed trends discerns enhanced rigidity in middle sections from reduced stiffness at terminal regions. Furthermore, distinctly depends on solvent polarity. oligomers maintain extended conformations nonpolar solvents exceeding 4 nm, while polar media, increased reduce 2 nm. These characteristics set key guidelines utility conjugates charge-transfer systems within organic electronics energy engineering.

Язык: Английский

Процитировано

1

Time-resolved vibrational spectroscopic study of molecular nanoaggregate photocatalysts DOI Creative Commons
Chao Li, Tao Liu,

Owen Thwaites

и другие.

Chemical Science, Год журнала: 2024, Номер unknown

Опубликована: Янв. 1, 2024

The controlled aggregation of organic chromophores into supramolecular structures offers a way to control and tune photocatalytic activity. However, the underlying mechanisms charge transfer accumulation are still unclear. Time-resolved vibrational spectroscopy is powerful structural probe for studying photogenerated intermediates. Here, we employ time-resolved infrared (TRIR) study CNP (2,6-bis(4-cyanophenyl)-4-(9-phenyl-9

Язык: Английский

Процитировано

0

Exciton Diffusion to Low Energy Sites of the Acceptor Drives Charge Photogeneration in D18:Y6 Solar Cells DOI Creative Commons
Thomas Sayner, Arvydas Ruseckas, Jonathon R. Harwell

и другие.

The Journal of Physical Chemistry C, Год журнала: 2024, Номер 128(45), С. 19319 - 19328

Опубликована: Окт. 31, 2024

We have investigated charge generation pathways in efficient organic photovoltaic blends of the polymer donor D18 and small-molecule acceptor Y6 using transient absorption time-resolved fluorescence spectroscopies. find that energy transfer from to outcompetes electron is followed by exciton diffusion regions disordered phase aggregates before hole D18. Aggregation molecules increases their ionization ∼0.3 eV provides a driving force for excitons spontaneously generated pairs observed ultrafast depolarization ground-state bleaching <200 fs, which indicates delocalization primary aggregates. This can explain spontaneous neat films Y6-rich blends. Our results show subtle aggregation control low-energy absorber be used balancing photocurrent with low voltage loss

Язык: Английский

Процитировано

0