Unidirectional Sidechain Engineering to Construct Dual‐Asymmetric Acceptors for 19.23 % Efficiency Organic Solar Cells with Low Energy Loss and Efficient Charge Transfer

Angewandte Chemie International Edition, Journal Year: 2023, Volume and Issue: 62(36)

Published: July 18, 2023

Achieving both high open-circuit voltage (Voc ) and short-circuit current density (Jsc to boost power-conversion efficiency (PCE) is a major challenge for organic solar cells (OSCs), wherein energy loss (Eloss inefficient charge transfer usually take place. Here, three new Y-series acceptors of mono-asymmetric asy-YC11 dual-asymmetric bi-asy-YC9 bi-asy-YC12 are developed. They share the same asymmetric D1 AD2 (D1 =thieno[3,2-b]thiophene D2 =selenopheno[3,2-b]thiophene) fused-core but have different unidirectional sidechain on side, allowing fine-tuned molecular properties, such as intermolecular interaction, packing pattern, crystallinity. Among binary blends, PM6 : one has better morphology with appropriate phase separation higher order than asy-YC9 bi-asy-YC11 ones. Therefore, bi-asy-YC12-based OSCs offer PCE 17.16 % Voc Jsc , due reduced Eloss efficient properties. Inspired by strong NIR-absorption, introduced into L8-BO construct ternary OSCs. Thanks broadened absorption, optimized morphology, furtherly minimized achieve champion 19.23 %, which highest efficiencies among these annealing-free devices. Our developed engineering constructing bi-asymmetric provides an approach

Language: Английский

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Alkoxy Modification of the Terminal Group in Nonfullerene Acceptors to Achieve Efficient Ternary Organic Solar Cells With a High Open‐Circuit Voltage

Advanced Functional Materials, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 13, 2025

Abstract Y‐series nonfullerene acceptors (NFAs) usually bear halogenated end groups to achieve narrow bandgaps and tunable molecules crystallinity; however, it results in small open‐circuit voltage ( V oc ) of 0.8–0.9 V. Here, three NFAs BTP‐eC9‐G51, BTP‐eC9‐G52, BTP‐eC9‐G53 are synthesized by introducing both an electron‐withdrawing fluoro group electron‐donating alkoxy commonly used 2‐(3‐oxo‐2,3‐dihydroinden1‐ylidene)‐malononitrile (IC) terminal groups. These compounds demonstrate a high larger than 0.9 when employed as organic solar cells (0.91 for BTP‐eC9‐G51 0.95 the others). The effect chain length on photoelectric properties is systematically studied. show that dipole moments aggregation behaviors these changes obviously with increase length. active layer based shows suitable phase separation structure good charge transport. Devices device efficiency 16.65%, higher those BTP‐eC9‐G52 devices (14.33% 13.24%, respectively). Furthermore, introduced into D18:L8‐BO third component, which improves J sc , reduces nonradiation energy loss, increased 19.03% 0.92

Language: Английский

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Organic small molecule acceptor materials for organic solar cells

eScience, Journal Year: 2023, Volume and Issue: 3(5), P. 100171 - 100171

Published: Aug. 6, 2023

The active layer of organic solar cells (OSCs) is composed a p-type conjugated polymer as the donor and an n-type semiconductor acceptor. Since report bulk-heterojunction OSCs with soluble C60 derivative PCBM acceptor in 1995, fullerene derivatives, including C70 PC71BM, have been dominant acceptors for 20 years. In 2015, A–D–A structured small molecule (SMA) was developed, which possesses advantages narrow bandgap, strong absorption long wavelength region, suitable electronic energy levels, contrast to acceptors. SMAs boost power conversion efficiency (PCE) 10–14% level. Recently, benefiting from innovation A–DA'D–A SMAs, PCE has rapidly increased 15% 19%. this review, development history materials briefly introduced. molecular structures physicochemical photovoltaic properties acceptors, derivatives bandgap are described. particular, effect regulating packing miscibility on their performance discussed. Finally, current challenges prospects analyzed

Language: Английский

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Optimized Crystal Framework by Asymmetric Core Isomerization in Selenium‐Substituted Acceptor for Efficient Binary Organic Solar Cells

Angewandte Chemie International Edition, Journal Year: 2023, Volume and Issue: 62(49)

Published: Oct. 12, 2023

Both the regional isomerization and selenium-substitution of small molecular acceptors (SMAs) play significant roles in developing efficient organic solar cells (OSCs), while their synergistic effects remain elusive. Herein, we developed three isomeric SMAs (S-CSeF, A-ISeF, A-OSeF) via subtly manipulating mono-selenium substituted position (central, inner, or outer) type heteroaromatic ring on central core by strategies for OSCs, respectively. Crystallography asymmetric A-OSeF presents a closer intermolecular π-π stacking more ordered 3-dimensional network packing charge-hopping pathways. With successive out-shift position, neat films give slightly wider band gap gradually higher crystallinity electron mobility. The PM1 : afford favourable fibrous phase separation morphology with charge transportation compared to other two counterparts. Consequently, A-OSeF-based devices achieve champion efficiency 18.5 %, which represents record value reported selenium-containing binary OSCs. Our precise engineering selenium-based provides promising approach optimizing crystal boosting top-ranked SMAs-based

Language: Английский

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The Asymmetric Strategy of Small‐Molecule Materials for Organic Solar Cells

Advanced Energy Materials, Journal Year: 2024, Volume and Issue: 14(17)

Published: Feb. 8, 2024

Abstract The conjugated small‐molecule materials of organic solar cells have always played a crucial role in light‐harvesting, charge transport, morphology optimization, and the attainment efficient devices. advancement novel understanding underlying molecular design rules serve as driving force for furthering stable photovoltaic Among variety principles, symmetry‐breaking strategy, which is well developed 3,9‐bis(2‐methylene‐(3‐(1,1‐dicyanomethylene)‐indanone))‐5,5,11,11‐tetrakis(4‐hexylphenyl)‐dithieno[2,3‐d:2′,3′‐d’]‐s‐indaceno[1,2‐b:5,6‐b’]dithiophene (ITIC)‐series acceptors, recently demonstrates great potential acceptors donors realizing high power conversion efficiency. In this review, order to give deep insight on asymmetric are systematically summarized with structure elucidate structure‐performance relationship, packing behaviors, evolution. Not only delicate balance between open circuit voltage short‐circuit current density, but also reductions recombination non‐radiative considered play key points improving performance when molecule used host or guest materials. Finally, concise challenges outlooks provided future development application molecules strategies.

Language: Английский

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Ethylenedioxythiophene‐Based Small Molecular Donor with Multiple Conformation Locks for Organic Solar Cells with Efficiency of 19.3 %

Angewandte Chemie International Edition, Journal Year: 2024, Volume and Issue: 63(25)

Published: April 16, 2024

Ternary organic solar cells (T-OSCs) represent an efficient strategy for enhancing the performance of OSCs. Presently, majority high-performance T-OSCs incorporates well-established Y-acceptors or donor polymers as third component. In this study, a novel class conjugated small molecules has been introduced component, demonstrating exceptional photovoltaic in T-OSCs. This innovative molecule comprises ethylenedioxythiophene (EDOT) bridge and 3-ethylrhodanine end group, with EDOT unit facilitating creation multiple conformation locks. Consequently, EDOT-based exhibits two-dimensional charge transport, distinguishing it from thiophene-bridged molecule, which displays fewer locks provides one-dimensional transport. Furthermore, robust electron-donating nature imparts cascade energy levels relative to electron acceptor. As result, OSCs incorporating component demonstrate enhanced mobilities, yielding remarkable efficiency 19.3 %, surpassing 18.7 % observed thiophene-based The investigations study underscore excellence building block constructing materials high carrier thereby contributing elevated

Language: Английский

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The Influence of Donor/Acceptor Interfaces on Organic Solar Cells Efficiency and Stability Revealed through Theoretical Calculations and Morphology Characterizations

Angewandte Chemie International Edition, Journal Year: 2024, Volume and Issue: 63(10)

Published: Jan. 8, 2024

Abstract End‐groups halogenation strategies, generally refers to fluorination and chlorination, have been confirmed as simple efficient methods regulate the photoelectric performance of non‐fullerene acceptors (NFAs), but a controversy over which one is better has existed for long time. Here, two novel NFAs, C9N3‐4F C9N3‐4Cl, featured with different end‐groups were successfully synthesized blended renowned donors, D18 PM6, electron‐withdrawing units. Detailed theoretical calculations morphology characterizations interface structures indicate NFAs based on possess binding energy miscibility shows an obvious influence phase‐separation morphology, charge transport behavior device performance. After verified by other three pairs reported universal conclusion obtained devices fluorination‐end‐groups‐based PM6 chlorination‐end‐groups‐based show excellent efficiencies, high fill factors stability. Finally, D18: PM6: C9N3‐4Cl yield outstanding efficiency 18.53 % 18.00 %, respectively. Suitably selecting donor regulating donor/acceptor can accurately present conversion ability points out way further molecular design selection high‐performance stable organic solar cells.

Language: Английский

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18.63% Efficiency of Ternary Organic Solar Cells Achieved via Nonhalogenated Solvent and Hot Spin‐Coating Process

Advanced Functional Materials, Journal Year: 2024, Volume and Issue: 34(27)

Published: March 5, 2024

Abstract The solubility problem of conjugated polymers in nonhalogenated solvents limits the application Organic solar cells (OSCs). By combining with a hot spin‐coating process, efficient PM6:BTP‐BO‐4F:GS‐ISO ternary OSCs are prepared by employing o‐xylene as solvent. After adding 10 wt% content GS‐ISO to PM6:BTP‐BO‐4F, surface morphology active layers is improved and charge extraction, transport, collection enhanced. Compared efficiency PM6:BTP‐BO‐4F (16.25%), an 18.63% achieved for OSCs. Moreover, 14.13% air. work provides new strategy preparing environmentally friendly using green solvents.

Language: Английский

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Halogenated Dibenzo[f,h]quinoxaline Units Constructed 2D‐Conjugated Guest Acceptors for 19% Efficiency Organic Solar Cells

Advanced Science, Journal Year: 2024, Volume and Issue: 11(31)

Published: June 17, 2024

Abstract Halogenation of Y‐series small‐molecule acceptors (Y‐SMAs) is identified as an effective strategy to optimize photoelectric properties for achieving improved power‐conversion‐efficiencies (PCEs) in binary organic solar cells (OSCs). However, the effect different halogenation 2D‐structured large π‐fused core guest Y‐SMAs on ternary OSCs has not yet been systematically studied. Herein, four 2D‐conjugated (X‐QTP‐4F, including halogen‐free H‐QTP‐4F, chlorinated Cl‐QTP‐4F, brominated Br‐QTP‐4F, and iodinated I‐QTP‐4F) by attaching halogens into 2D‐conjugation extended dibenzo[ f , h ]quinoxaline are developed. Among these X‐QTP‐4F, Cl‐QTP‐4F a higher absorption coefficient, optimized molecular crystallinity packing, suitable cascade energy levels, complementary with PM6:L8‐BO host. Moreover, among PM6:L8‐BO:X‐QTP‐4F blends, PM6:L8‐BO:Cl‐QTP‐4F obtains more uniform size‐suitable fibrillary network morphology, well vertical phase distribution, thus boosting charge generation, transport, extraction, suppressing loss OSCs. Consequently, PM6:L8‐BO:Cl‐QTP‐4F‐based achieve 19.0% efficiency, which state‐of‐the‐art based superior devices host (17.70%) guests H‐QTP‐4F (18.23%), Br‐QTP‐4F (18.39%), I‐QTP‐4F (17.62%). The work indicates that promising gain efficient

Language: Английский

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Multi‐Selenophene Strategy Enables Dimeric Acceptors‐Based Organic Solar Cells with over 18.5% Efficiency

Advanced Energy Materials, Journal Year: 2024, Volume and Issue: 14(30)

Published: May 9, 2024

Abstract Dimeric acceptor (DMA) becomes a promising alternative to small‐molecular and polymeric acceptor‐based organic solar cells (OSCs) due its well‐defined chemical structure, high batch‐to‐batch reproducibility, low molecular diffusion properties. However, DMAs usually exhibit blueshifted absorptions, limiting their photon utilization abilities. Herein, multi‐selenophene strategies are adopted develop redshifted DMAs. From monomer (YSe) dimers (DYSe‐1 DYSe‐2), reduced electron reorganization energies exciton binding enable the efficient charge dynamics in DMAs‐based OSCs. Together with effective absorption extending ≈920 nm, DYSe‐1‐ DYSe‐2‐ based OSCs outstanding short‐circuit current densities ( J SC s) over 27 mA cm −2 , which best among Besides, compared YSe‐based device, both DMA‐based devices have higher electroluminescence quantum efficiencies thus reduce nonradiative recombination loss (ΔE 3 ), contributing energy losses. The resultant open‐circuit voltages V OC of ≈0.88 V, which, combining super values, lead power conversion 18.56% 18.22%, respectively. These results highlight great potential strategy for development performance.

Language: Английский

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