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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Non-fullerene acceptors with high crystallinity and photoluminescence quantum yield enable >20% efficiency organic solar cells

Nature Materials, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 29, 2025

Language: Английский

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Recent progress in side chain engineering of Y-series non-fullerene molecule and polymer acceptors

Science China Chemistry, Journal Year: 2023, Volume and Issue: 67(3), P. 788 - 805

Published: Nov. 29, 2023

Language: Английский

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Selenium‐Substitution Asymmetric Acceptor Enables Efficient Binary Organic Solar Cells over 18.3% via Regulating Molecular Stacking and Phase Separation

Advanced Energy Materials, Journal Year: 2023, Volume and Issue: 13(29)

Published: June 14, 2023

Abstract Substantial efforts of A–DA′D–A type non‐fullerene acceptors (NFAs) molecular design have impelled power conversion efficiency (PCE) single junction organic solar cells (OSCs) to exceed 19%. Asymmetric geometry strategy, selenium‐substitution, and end‐group engineering are proven be effective modification methods. Here, two novel selenium substitution asymmetric NFAs, AsymSSe‐2F, AsymSSe‐2Cl, synthesized investigate the synergistic effects on device performance compared with symmetric Y6. When blending AsymSSe‐2F wide‐bandgap high crystallinity polymer D18, a remarkable PCE 18.31% is yielded, an excellent fill factor 79.46% achieved, which attributed broadened absorption, enhanced π – stacking, balanced carrier mobilities, fine phase‐separation morphology. Notably, among reported selenium‐substituted NFAs based OSCs, especially combined seldom‐reported this top‐ranked in binary bulk heterojunction cells. This work indicates that promising strategy for fabricating OSCs.

Language: Английский

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High Miscibility‐Induced Reduction of Trap Density in All‐Polymer Solar Cells Using Hybrid Cyclohexyl‐Hexyl Side Chains

Advanced Functional Materials, Journal Year: 2023, Volume and Issue: 33(40)

Published: Aug. 30, 2023

Abstract Reducing the trap density within organic solar cells is of vital importance to realize high power conversion efficiency (PCE); however, research focusing on this aspect limited in all‐polymer (All‐PSCs). In work, it found that can be dramatically reduced by simultaneously obtaining miscibility donor and acceptor ordered packing blend films through substituting ethylhexyl with hybrid cyclohexyl‐hexyl side chains design polymer donor. D18‐ChCl has a slightly lower aggregation behavior relative D18‐Cl counterpart, but reveals synchronously higher crystallinity PYF‐T‐o. Such morphology evolution positively affects electronic properties device—prolongs carrier lifetime, facilitates exciton dissociation, lowers energy disorder. As result, All‐PSC devices based exhibited remarkable PCE 17.1%, low 2.65 × 10 15 cm −3 , disorder 47 meV as well outstanding stability mechanical durability. This result demonstrates alkyl engineering delicately improves miscibility, drives density, refines device performance, which brings vibrancy field.

Language: Английский

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Central Core Substitutions and Film‐Formation Process Optimization Enable Approaching 19% Efficiency All‐Polymer Solar Cells

Advanced Materials, Journal Year: 2023, Volume and Issue: 35(51)

Published: Oct. 6, 2023

Molecular interactions and film-formation processes greatly impact the blend film morphology device performances of all-polymer solar cells (all-PSCs). structure, such as central cores polymer acceptors, would significantly influence this process. Herein, core substitutions acceptors are adjusted three quinoxaline (Qx)-fused-core-based materials, PQx1, PQx2, PQx3 synthesized. The molecular aggregation ability intermolecular interaction systematically regulated, which subsequently process determine resulting morphology. As a result, PQx3, with favorable moderate donor PM6, achieves efficient all-PSCs high power conversion efficiency (PCE) 17.60%, could be further improved to 18.06% after carefully optimizing annealing interface layer. This impressive PCE is one highest values for binary based on classical PM6. PYF-T-o also involved in promoting light utilization, ternary shows an 18.82%. In addition, PM6:PQx3-based devices exhibit film-thickness tolerance, superior stability, considerable potential large-scale (16.23% 1 cm2 device). These results highlight importance structure optimization control obtaining stable all-PSCs.

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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Correlating Aggregation Ability of Polymer Donors with Film Formation Kinetics for Organic Solar Cells with Improved Efficiency and Processability

Advanced Materials, Journal Year: 2024, Volume and Issue: 36(29)

Published: May 4, 2024

Film formation kinetics significantly impact molecular processability and power conversion efficiency (PCE) of organic solar cells. Here, two ternary random copolymerization polymers are reported, D18─N-p D18─N-m, to modulate the aggregation ability D18 by introducing trifluoromethyl-substituted pyridine unit at para- meta-positions, respectively. The introduction reduces material adjusts interactions with acceptor L8-BO, thereby leading largely changed film earlier phase separation longer times, which enlarge fiber sizes in blend films improve carrier generation transport. As a result, moderate delivers high PCE 18.82% is further improved 19.45% via interface engineering. Despite slightly inferior small area device performances, D18─N-m shows solubility, inspires adjust ratio meta-trifluoromethyl carefully obtain polymer donor D18─N-m-10 good solubility nonhalogenated solvent o-xylene. High PCEs 13.07% 12.43% 1 cm

Language: Английский

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Small molecule donor third component incorporating thieno[3,2-b]thiophene unit enables 19.18% efficiency ternary organic solar cells with improved operational stability

Nano Energy, Journal Year: 2024, Volume and Issue: 125, P. 109542 - 109542

Published: March 24, 2024

Language: Английский

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Realizing over 18% Efficiency for M‐Series Acceptor‐Based Polymer Solar Cells by Improving Light Utilization

Advanced Energy Materials, Journal Year: 2024, Volume and Issue: unknown

Published: July 2, 2024

Abstract M‐series molecules are one kind of promising acceptor‐donor‐acceptor (A‐D‐A)‐type acceptors for constructing high‐performance organic solar cells (OSCs). However, their power conversion efficiencies (PCEs) lagging behind that current state‐of‐the‐art OSCs, limited by the relatively low fill factor (FF) and photocurrent. Herein, combined strategies layer‐by‐layer (LBL) deposition interface engineering conducted to systematically improve light utilization thus PCEs M36‐based OSCs. Through choosing a proper processing solvent, PCE 17.3% with an FF 77.9% is achieved resulting LBL devices, much higher than those (15.9%/74.0%) from blend‐casting devices. The improvement assigned favorable morphological evolution facilitates carrier generation transport as well reduces charge recombination. More importantly, light‐harvesting active layers can be enhanced upon employing self‐assembled monolayer (2‐(9H‐carbazol‐9‐yl)ethyl)phosphonic acid (2PACz) instead widely used PEDOT:PSS hole‐selecting layer, due decreased parasitic absorption former. Consequently, 2PACz‐based devices exhibit significantly increased photocurrent, affording up 18.2%, which highest among reported A‐D‐A‐type acceptor‐based These results deliver important enhance performance OSCs highlight great potential practical applications.

Language: Английский

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