Oligomerized Fused‐Ring Electron Acceptors for Efficient and Stable Organic Solar Cells

Angewandte Chemie International Edition, Journal Year: 2023, Volume and Issue: 62(46)

Published: July 12, 2023

Abstract Organic solar cells (OSCs) have attracted wide research attention in the past decades. Very recently, oligomerized fused‐ring electron acceptors (OFREAs) emerged as a promising alternative to small‐molecular/polymeric acceptor‐based OSCs due their unique advantages such well‐defined structures, batch reproducibility, good film formation, low diffusion coefficient, and excellent stability. So far, rapid advances been made development of OFREAs consisting directly/rigidly/flexibly linked oligomers fused ones. In this Minireview, we systematically summarized recent progress OFREAs, including structural diversity, synthesis approach, molecular conformation packing, long‐term Finally, conclude with future perspectives on challenges be addressed potential directions. We believe that Minireview will encourage novel for OSC applications.

Language: Английский

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Tunable Donor Aggregation Dominance in a Ternary Matrix of All‐Polymer Blends with Improved Efficiency and Stability

Advanced Materials, Journal Year: 2023, Volume and Issue: 36(15)

Published: July 7, 2023

Abstract Using two structurally similar polymer acceptors in constructing high‐efficiency ternary all‐polymer solar cells is a widely acknowledged strategy; however, the focus thus far has not been on how acceptor(s) would tune aggregation of donors, and furthermore film morphology device performance (efficiency stability). Herein, it reported that matching celebrity acceptor PY‐IT donor PBQx‐TCl results enhanced H ‐ PBQx‐TCl, which can be finely tuned by controlling amount second PY‐IV. Consequently, efficiency‐optimized PY‐IV weight ratio (0.2/1.2) leads to state‐of‐the‐art power conversion efficiency 18.81%, wherein light‐illuminated operational stability also along with well‐protected thermal stability. Such enhancements stabilities attributed optimization desired glass transition temperature target active layer based comprehensive characterization. In addition being high‐power case for cells, these are successful attempt using combined toward optimal morphology, provides theoretical basis construction other types organic photovoltaics beyond cells.

Language: Английский

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Two-Dimensional Conjugation Extended CH-Series Acceptors with a Distinctive A–D–A Character

Accounts of Materials Research, Journal Year: 2023, Volume and Issue: 4(9), P. 772 - 785

Published: Aug. 2, 2023

ConspectusAs one of the most important indicators for evaluating photovoltaic devices, power conversion efficiencies (PCEs) first-class organic solar cells (OSCs) have reached level ∼20%, but they still lag far behind that over 25% their inorganic counterparts. With similar if not better fill factor and short-circuit current, this wide gap PCEs should be fundamentally attributed to greatly larger nonradiative energy losses in OSCs, which are usually above 0.2 eV OSCs only 0.03–0.04 high-performance cells. Note stubbornly severe recombination is associated with multiple characteristics light-harvesting molecules, such as intrinsically large exciton binding energies small relative dielectric constants, defective intermolecular packing networks, or more crystal defects caused by flexibility molecular skeletons, nonideal nanoscale film morphologies, so on. All factors require rational design molecules carried out at single molecule also aggregation levels further dramatic improvement PCE achieved OSCs.In Account, we will first expound unique merits acceptor–donor–acceptor (A–D–A) type materials frontier orbital distribution, tuning, packings, meanwhile revealing dominant role A–D–A facilitating charge transfer/transport, suppressing loss, improving performance eventually. In light conspicuous superiority a convincing conclusion can made exploration novel crucially shrink between Second, our recent studies really exciting platform (CH-series) discussed comprehensively, involving various nonfullerene acceptors (NFAs) molecular, dimer-like, polymerized architectures. distinctive feature CH-series NFAs two-dimensional (2D) conjugation extension, especially central units. Therefore, favorable effects 2D extension these on fundamental physicochemical properties, modes, blended parameters, resulting fully discussed. Abiding unveiled rules NFAs, highest approaching 20% has been based molecules. The evolution path previous traditional PCBM, ITIC, Y6, etc. could lesson; very likely offer great capable achieving record-breaking along much decreased losses, considering structural modification possibilities. Finally, despite rapidly surging there several insurmountable hurdles when attempting break through bottlenecks existing OSCs. propose some perspectives conducted may conquer challenge too thus boost toward commercial applications further.

Language: Английский

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Over 19 % Efficiency Organic Solar Cells Enabled by Manipulating the Intermolecular Interactions through Side Chain Fluorine Functionalization

Angewandte Chemie International Edition, Journal Year: 2024, Volume and Issue: 63(15)

Published: Feb. 8, 2024

Fluorine side chain functionalization of non-fullerene acceptors (NFAs) represents an effective strategy for enhancing the performance organic solar cells (OSCs). However, a knowledge gap persists regarding relationship between structural changes induced by fluorine and resultant impact on device performance. In this work, varying amounts atoms were introduced into outer chains Y-series NFAs to construct two named BTP-F0 BTP-F5. Theoretical experimental investigations reveal that side-chain fluorination significantly increase overall average electrostatic potential (ESP) charge balance factor, thereby effectively improving ESP-induced intermolecular interaction, thus precisely tuning molecular packing bulk-heterojunction morphology. Therefore, BTP-F5-based OSC exhibited enhanced crystallinity, domain purity, reduced spacing, optimized phase distribution in vertical direction. This facilitates exciton diffusion, suppresses recombination, improves extraction. Consequently, promising power conversion efficiency (PCE) 17.3 % 19.2 achieved binary ternary devices, respectively, surpassing PCE 16.1 BTP-F0-based OSCs. work establishes structure-performance demonstrates is compelling achieving ideal separation highly efficient

Language: Английский

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The Development of Quinoxaline‐Based Electron Acceptors for High Performance Organic Solar Cells

Advanced Materials, Journal Year: 2024, Volume and Issue: 36(33)

Published: June 19, 2024

In the recent advances of organic solar cells (OSCs), quinoxaline (Qx)-based nonfullerene acceptors (QxNFAs) have attracted lots attention and enabled recorded power conversion efficiency approaching 20%. As an excellent electron-withdrawing unit, Qx possesses advantages many modifiable sites, wide absorption range, low reorganization energy, so on. To develop promising QxNFAs to further enhance photovoltaic performance OSCs, it is necessary systematically summarize reported far. this review, all focused are classified into five categories as following: SM-Qx, YQx, fused-YQx, giant-YQx, polymer-Qx according molecular skeletons. The design concepts, relationships between structure optoelectronic properties, intrinsic mechanisms device discussed in detail. At end, kind materials summed up, direction prospected, challenges faced by given, constructive solutions existing problems advised. Overall, review presents unique viewpoints conquer challenge thus boost OSCs development toward commercial applications.

Language: Английский

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A Broad-Spectrum Solid Additive to Further Boost High-Efficiency Organic Solar Cells via Morphology Regulation

ACS Energy Letters, Journal Year: 2023, Volume and Issue: 8(8), P. 3494 - 3503

Published: July 24, 2023

Given the great potential for achieving record breaking organic solar cells (OSCs), newly explored solid additives that could optimize nanoscale morphology of active layers have rapidly gained widespread attention. Herein, a new volatile additive 2,5-dichlorothieno[3,2-b]thiophene (TT-Cl) is delicately explored, fully satisfying design criteria planar conjugated skeleton with suitable molecular size, symmetrical geometry, and proper halogenation. When applied in state-of-the-art OSCs diverse layers, quite high crystallinity TT-Cl strong interactions light-harvesting components lead to optimized crystalline ordering, fibrillar networks, vertical phase distributions, thus offering significant performance enhancement. Consequently, PM6:Y6-based binary ternary achieved PCEs 18.20% 18.95%, respectively. Moreover, PM6:CH23-based presented an outstanding PCE 18.72%. Our work not only provides broad-spectrum film morphologies powerfully but also manifests record-breaking OSCs.

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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High‐Efficiency Organic Solar Cells Enabled by Non‐Fullerene Acceptors with Benzimidazole as the Central Core

Advanced Functional Materials, Journal Year: 2023, Volume and Issue: 33(48)

Published: July 19, 2023

Abstract Electron‐deficient central core plays a crucial role in the construction of efficient Y‐series non‐fullerene acceptors (NFAs). Here, fused‐ring benzimidazole (BIm) served as for first time to yield new NFA named MZ‐1 and its structural analogue MZ‐2, which is obtained by replacing methyl group on 2C position BIm with trifluoromethyl group. Compared MZ‐1, MZ‐2 shows obviously blue‐shifted absorption lowers highest occupied molecular orbital (HOMO) energy level that more matched polymer donor PM6. Benefiting from charge transport favorable microphase separation morphology active layer, acceptor MZ‐2‐based device affords an excellent power conversion efficiency (PCE) 17.31% along high open‐circuit voltage ( V oc ) 0.903 V, short‐circuit current density J sc 26.32 mA cm −2 fill factor (FF) 72.83%, remarkably superior MZ‐1‐based devices PCE 10.70%. This study offers valuable insight into design enrich Y series NFAs high‐performance organic solar cells (OSCs).

Language: Английский

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Quinoxaline-based nonfullerene acceptors with powerful core-functionalization ability enabling efficient solar energy utilization

Energy & Environmental Science, Journal Year: 2024, Volume and Issue: 17(14), P. 4944 - 4967

Published: Jan. 1, 2024

Quinoxaline-based nonfullerene acceptors show highly tunable photoelectric properties and superior performance for sunlight utilization enabled by their powerful core-functionalization ability.

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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