19.7% efficiency binary organic solar cells achieved by selective core fluorination of nonfullerene electron acceptors

Joule, Год журнала: 2024, Номер 8(3), С. 835 - 851

Опубликована: Янв. 30, 2024

Язык: Английский

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18.2%-efficient ternary all-polymer organic solar cells with improved stability enabled by a chlorinated guest polymer acceptor

Joule, Год журнала: 2023, Номер 7(1), С. 221 - 237

Опубликована: Янв. 1, 2023

Язык: Английский

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A rare case of brominated small molecule acceptors for high-efficiency organic solar cells

Nature Communications, Год журнала: 2023, Номер 14(1)

Опубликована: Авг. 5, 2023

Abstract Given that bromine possesses similar properties but extra merits of easily synthesizing and polarizing comparing to homomorphic fluorine chlorine, it is quite surprising very rare high-performance brominated small molecule acceptors have been reported. This may be caused by undesirable film morphologies stemming from relatively larger steric hindrance excessive crystallinity bromides. To maximize the advantages bromides while circumventing weaknesses, three (CH20, CH21 CH22) are constructed with stepwise brominating on central units rather than conventional end groups, thus enhancing intermolecular packing, dielectric constant them without damaging favorable packing through groups. Consequently, PM6:CH22-based binary organic solar cells render highest efficiency 19.06% for acceptors, more excitingly, a record-breaking 15.70% when further thickening active layers ~500 nm. By exhibiting such acceptor, our work highlights great potential achieving delicately brominating.

Язык: Английский

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3D acceptors with multiple A–D–A architectures for highly efficient organic solar cells

Energy & Environmental Science, Год журнала: 2023, Номер 16(4), С. 1773 - 1782

Опубликована: Янв. 1, 2023

Efficient 3D NFAs through central unit connection blaze a new trail in further molecular structural optimization of state-of-the-art NFAs.

Язык: Английский

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High‐Performance Organic Solar Cells Containing Pyrido[2,3‐b]quinoxaline‐Core‐Based Small‐Molecule Acceptors with Optimized Orbit Overlap Lengths and Molecular Packing

Angewandte Chemie International Edition, Год журнала: 2023, Номер 62(30)

Опубликована: Май 26, 2023

Abstract The central core in A‐DA 1 D‐A‐type small‐molecule acceptor (SMAs) plays an important role determining the efficiency of organic solar cells (OSCs), while principles governing efficient design SMAs remain elusive. Herein, we developed a series with pyrido[2,3‐ b ]quinoxaline (PyQx) as new electron‐deficient unit by combining cascade‐chlorination strategy, namely Py1, Py2, Py3, Py4 and Py5. introduction chlorine atoms reduces intramolecular charge transfer effects but elevates LUMO values. Density functional theory (DFT) reveals that Py2 ortho substituted PyQx Py5 two yield larger dipole moments smaller π⋅⋅⋅π stacking distances, compared other three acceptors. Moreover, shows strongest light absorption capability induced extended orbit overlap lengths more packing structures dimers. These features endow best device performance due to better molecular aggregation behaviors, suitable domain sizes exciton dissociation recombination. This study highlights significance incorporating large moments, small distances dimers into development high‐performance SMAs, providing insight for OSCs.

Язык: Английский

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Effects of Halogenation of Small‐Molecule and Polymeric Acceptors for Efficient Organic Solar Cells

Advanced Functional Materials, Год журнала: 2023, Номер 33(22)

Опубликована: Фев. 23, 2023

Abstract Tuning the properties of non‐fullerene acceptors (NFAs) through halogenation, including fluorination and chlorination, represents one most promising strategies to boost performance organic solar cells (OSCs). However, it remains unclear how F Cl choice influences molecular packing between small‐molecule polymeric acceptors. Here, a series with different amounts types halogenation is synthesized, effects chlorination are investigated. It found that chlorinated lead longer exciton diffusion length better compared corresponding fluorinated ones, which attributes their stronger intermolecular mode. For polymer acceptors, in contrast, polymers achieve denser mode performance, because exhibit reduced intrachain conjugation end group moieties linker units. This study demonstrates on modes performances for provides important guidance molecule design high‐performance OSCs.

Язык: Английский

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Complete Peripheral Fluorination of the Small‐Molecule Acceptor in Organic Solar Cells Yields Efficiency over 19 %

Angewandte Chemie International Edition, Год журнала: 2023, Номер 62(44)

Опубликована: Сен. 14, 2023

Due to the intrinsically flexible molecular skeletons and loose aggregations, organic semiconductors, like small acceptors (SMAs) in solar cells (OSCs), greatly suffer from larger structural/packing disorders weaker intermolecular interactions comparing their inorganic counterparts, further leading hindered exciton diffusion/dissociation charge carrier migration resulting OSCs. To overcome this challenge, complete peripheral fluorination was performed on basis of a two-dimensional (2D) conjugation extended platform CH-series SMAs, rendering an acceptor CH8F with eight fluorine atoms surrounding backbone. Benefitting broad 2D backbone, more importantly, strengthened fluorine-induced secondary interactions, its D18 blends afford much enhanced ordered packings accompanying enlarged dielectric constants, reduced binding energies obvious fibrillary networks CH6F controls. Consequently, D18:CH8F-based OSCs reached excellent efficiency 18.80 %, better than that 17.91 % for CH6F-based ones. More excitingly, by employing D18-Cl possesses highly similar structure as third component, highest 19.28 SMAs-based has been achieved so far. Our work demonstrates dramatical structural multiformity meanwhile, high potential constructing record-breaking through fine-tuning.

Язык: Английский

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Electronic Configuration Tuning of Centrally Extended Non‐Fullerene Acceptors Enabling Organic Solar Cells with Efficiency Approaching 19 %

Angewandte Chemie International Edition, Год журнала: 2023, Номер 62(42)

Опубликована: Авг. 26, 2023

In the molecular optimizations of non-fullerene acceptors (NFAs), extending central core can tune energy levels, reduce nonradiative loss, enhance intramolecular (donor-acceptor and acceptor-acceptor) packing, facilitate charge transport, improve device performance. this study, a new strategy was employed to synthesize featuring conjugation-extended electron-deficient cores. Among these, acceptor CH-BBQ, embedded with benzobisthiadiazole, exhibited an optimal fibrillar network morphology, enhanced crystallinity, improved generation/transport in blend films, leading power conversion efficiency 18.94 % for CH-BBQ-based ternary organic solar cells (OSCs; 18.19 binary OSCs) owing its delicate structure design electronic configuration tuning. Both experimental theoretical approaches were used systematically investigate influence on properties The modulation paves pathway engineering NFAs, propelling relevant research forward.

Язык: Английский

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Correlation of Local Isomerization Induced Lateral and Terminal Torsions with Performance and Stability of Organic Photovoltaics

Journal of the American Chemical Society, Год журнала: 2023, Номер 145(10), С. 5909 - 5919

Опубликована: Март 6, 2023

Organic photovoltaics (OPVs) have achieved great progress in recent years due to delicately designed non-fullerene acceptors (NFAs). Compared with tailoring of the aromatic heterocycles on NFA backbone, incorporation conjugated side-groups is a cost-effective way improve photoelectrical properties NFAs. However, modifications also need consider their effects device stability since molecular planarity changes induced by are related aggregation and evolution blend morphology under stresses. Herein, new class NFAs local-isomerized developed impact local isomerization geometries performance/stability systematically investigated. The based one isomers balanced side- terminal-group torsion angles can deliver an impressive power conversion efficiency (PCE) 18.5%, low energy loss (0.528 V) excellent photo- thermal stability. A similar approach be applied another polymer donor achieve even higher PCE 18.8%, which among highest efficiencies obtained for binary OPVs. This work demonstrates effectiveness applying fine-tune side-group steric effect non-covalent interactions between therefore improving both photovoltaic performance fused ring NFA-based

Язык: Английский

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A Bithiazole‐Substituted Donor for High‐Efficiency Thick Ternary Organic Solar Cells via Regulation of Crystallinity and Miscibility

Advanced Energy Materials, Год журнала: 2023, Номер 13(23)

Опубликована: Май 1, 2023

Abstract Organic solar cells (OSCs) with thick active layers exhibit great potential for future roll‐to‐roll mass production. However, increasing the thickness of layer generally leads to unfavorable morphology, which decreases device's performance. Therefore, it is a critical challenge achieve OSCs high efficiency and film simultaneously. Herein, small molecular donor, ZW1, incorporating bithiazole unit along thiophene group as π ‐bridge reported. ZW1 crystallinity employed fabricate D18:ZW1:Y6 ternary devices, enhances crystallization, optimizes suppresses bimolecular recombination. Additionally, shows better miscibility D18, resulting in preferred vertical phase distribution. As result, an outstanding power conversion (PCE) 18.50% realized 120 nm thickness. Importantly, attain PCE 16.67% (thickness ≈300 nm), significantly higher than corresponding binary devices (13.50%). The one highest values thick‐film reported date. This work demonstrates that incorporation highly crystalline small‐molecule donors into OSCs, possessing good host materials, presents effective strategy fabricating efficient OSCs.

Язык: Английский

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