Over 19.2% efficiency of layer-by-layer organic photovoltaics enabled by a highly crystalline material as an energy donor and nucleating agent

Energy & Environmental Science, Год журнала: 2024, Номер 17(14), С. 5173 - 5182

Опубликована: Янв. 1, 2024

By introducing highly crystalline material D18A into donor layer acting as energy and nucleating agent, an optimal PCE of 19.25% was achieved for PM1 : D18A/L8-BO based OPVs.

Язык: Английский

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Strengthening Near‐Infrared Photon Harvesting in Semi‐Transparent All‐Polymer Solar Cells through the Synergy of Fluorination on the Selenide Monomer Backbone

Advanced Functional Materials, Год журнала: 2024, Номер 34(33)

Опубликована: Апрель 26, 2024

Abstract All‐polymer solar cells (all‐PSCs) offer promising potential for large‐scale manufacturing due to their remarkable mechanical and thermal stability. However, the limited capacity of polymer acceptors near‐infrared (NIR) photon harvesting has impeded progress in semi‐transparent (ST) all‐PSCs. Here, study develops a pair new NIR acceptors, named PYSeF‐T PYSe2F‐T, with mono‐/di‐fluorinated end groups capped selenide monomer backbone, respectively. Owing stronger intermolecular interaction intramolecular charge transfer effect di‐fluorinated PYSe2F‐T exhibits crystallinity more bathochromic absorption 1000 nm. When blended donor, PM6, PY2SeF‐T‐based all‐PSC demonstrates higher efficiency 16.73% short‐circuit current ( J SC ) 27.7 mA cm −2 , which is highest Based on these, ST device based PM6:PYSe2F‐T superior 12.52% an average visible transmittance 26.2% light utilization 3.28%, outperforming mono‐fluorinated counterpart. The work provides in‐depth understanding above synergistic effects develop establishes solid foundation future investigations into large‐area flexible

Язык: 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, Год журнала: 2023, Номер 62(49)

Опубликована: Окт. 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

Язык: Английский

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Precise Methylation Yields Acceptor with Hydrogen‐Bonding Network for High‐Efficiency and Thermally Stable Polymer Solar Cells

Angewandte Chemie International Edition, Год журнала: 2023, Номер 63(6)

Опубликована: Дек. 15, 2023

Abstract Utilizing intermolecular hydrogen‐bonding interactions stands for an effective approach in advancing the efficiency and stability of small‐molecule acceptors (SMAs) polymer solar cells. Herein, we synthesized three SMAs (Qo1, Qo2, Qo3) using indeno[1,2‐ b ]quinoxalin‐11‐one (Qox) as electron‐deficient group, with incorporation a methylation strategy. Through crystallographic analysis, it is observed that two Qox‐based methylated (Qo2 exhibit multiple hydrogen bond‐assisted 3D network transport structures, contrast to 2D structure gem‐dichlorinated counterpart (Qo4). Notably, Qo2 exhibits stronger compared Qo3. Consequently, PM6 : device realizes highest power conversion (PCE) 18.4 %, surpassing efficiencies devices based on Qo1 (15.8 %), Qo3 (16.7 Qo4 (2.4 %). This remarkable PCE can be primarily ascribed enhanced donor‐acceptor miscibility, more favorable medium structure, efficient charge transfer collection behavior. Moreover, demonstrates exceptional thermal stability, retaining 82.8 % its initial after undergoing annealing at 65 °C 250 hours. Our research showcases precise methylation, particularly targeting formation tune crystal packing patterns, represents promising strategy molecular design stable SMAs.

Язык: 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, Год журнала: 2023, Номер 13(29)

Опубликована: Июнь 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.

Язык: Английский

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Unraveling the Structure–Property–Performance Relationships of Fused-Ring Nonfullerene Acceptors: Toward a C-Shaped ortho-Benzodipyrrole-Based Acceptor for Highly Efficient Organic Photovoltaics

Journal of the American Chemical Society, Год журнала: 2023, Номер 146(1), С. 833 - 848

Опубликована: Дек. 19, 2023

The high-performance Y6-based nonfullerene acceptors (NFAs) feature a C-shaped A-DA'D-A-type molecular architecture with central electron-deficient thiadiazole (Tz) A' unit. In this work, we designed and synthesized new A-D-A-type NFA, termed CB16, having ortho-benzodipyrrole-based skeleton of Y6 but the Tz unit eliminated. When processed nonhalogenated xylene without using any additives, binary PM6:CB16 devices display remarkable power conversion efficiency (PCE) 18.32% high open-circuit voltage (Voc) 0.92 V, surpassing performance corresponding devices. contrast, similarly SB16, featuring an S-shaped para-benzodipyrrole-based skeleton, yields low PCE 0.15% due to strong side-chain aggregation SB16. A-DNBND-A in CB16 Y6-series NFAs constitutes essential structural foundation for achieving exceptional device performance. moiety or other units can be employed finely adjust intermolecular interactions. single-crystal X-ray structure reveals that ortho-benzodipyrrole-embedded plays important role formation 3D elliptical network packing efficient charge transport. Solution structures PM6:NFAs detected by small- wide-angle scattering (SWAXS) indicate removing could reduce self-packing thereby enhancing complexing networking PM6 spin-coating solution subsequent film. Elucidating structure–property–performance relationships work paves way future development structurally simplified NFAs.

Язык: Английский

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High‐Performance Ternary Organic Solar Cells with Enhanced Luminescence Efficiency and Miscibility Enabled by Two Compatible Acceptors

Advanced Energy Materials, Год журнала: 2024, Номер 14(12)

Опубликована: Янв. 28, 2024

Abstract The ternary strategy has proven to be an effective method for improving the efficiency of organic solar cells (OSCs). However, designing and selecting third component still pose challenges. In this study, issue is addressed by focusing on PBDB‐T:Y18‐F binary system introducing a new, strong luminescent, asymmetric small‐molecule acceptor (SMA) called L8‐CBIC‐Cl, which shares similar skeleton with Y18‐F. similarity in molecular framework facilitates good compatibility between two acceptors, resulting formation alloy‐like phase. Furthermore, norbornenyl‐modified end group L8‐CBIC‐Cl contributes its luminescent properties, turn leads low non‐radiative energy loss high open‐circuit voltage. Consequently, PBDB‐T:L8‐CBIC‐Cl:Y18‐F based devices realize power conversion (PCE) up 17.01%, higher than device (14.49%). Importantly, exhibits universality as guest other three systems (D18:Y6, D18:BTP‐eC9‐4F, D18:L8‐BO). D18:L8‐BO:L8‐CBIC‐Cl shows impressive 19%. work demonstrates that employing SMA PLQY better miscibility host great potential developing high‐efficiency OSCs.

Язык: Английский

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Selenium substitution for dielectric constant improvement and hole-transfer acceleration in non-fullerene organic solar cells

Nature Communications, Год журнала: 2024, Номер 15(1)

Опубликована: Март 7, 2024

Abstract Dielectric constant of non-fullerene acceptors plays a critical role in organic solar cells terms exciton dissociation and charge recombination. Current feature dielectric 3-4, correlating to relatively high recombination loss. We demonstrate that selenium substitution on acceptor central core can effectively modify molecule constant. The corresponding blend film presents faster hole-transfer ~5 ps compared the sulfur-based derivative (~10 ps). However, blends with Se-acceptor also show after 100 upon optical pumping, which is explained by disordered stacking Se-acceptor. Encouragingly, dispersing an optimized cell system interrupt aggregation while still retain With improved fibril morphology, ternary device exhibits obvious reduction non-radiative 0.221 eV efficiency 19.0%. This work unveils heteroatom-substitution induced improvement, associated dynamics morphology manipulation, finally contributes better material/device design performance.

Язык: Английский

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3D Crystal Framework Regulation Enables Se‐Functionalized Small Molecule Acceptors Achieve Over 19% Efficiency

Advanced Energy Materials, Год журнала: 2024, Номер 14(19)

Опубликована: Март 10, 2024

Abstract Se‐functionalized small molecule acceptors (SMAs) exhibit unique advantages in constructing materials with near‐infrared absorption, but their photovoltaic performance lags behind that of S‐containing analogs organic solar cells (OSCs). Herein, two new Se‐containing SMAs, namely Se‐EH and Se‐EHp, are designed synthesized by regulating bifurcation site outer alkyl chain, which enables Se‐EHp to form different 3D crystal frameworks from CH1007. displays tighter π–π stacking denser packing framework smaller‐sized pore structure induced larger steric hindrance effect chain branched at 2‐position, a higher dielectric constant PM6:Se‐EH active layer can be obtained. OSCs based on achieved very high PCEs 18.58% binary 19.03% ternary devices FF approaching 80% for SMAs. A more significant adjusts the molecular crystallization favorable nanofiber interpenetrating network an appropriate domain size reduce rate sub‐ns recombination promote balanced transport carriers. This work provides references further design development highly efficient

Язык: Английский

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Manipulating Alkyl Inner Side Chain of Acceptor for Efficient As‐Cast Organic Solar Cells

Advanced Materials, Год журнала: 2024, Номер unknown

Опубликована: Июль 16, 2024

As-cast organic solar cells (OSCs) possess tremendous potential for low-cost commercial applications. Herein, five small-molecule acceptors (A1-A5) are designed and synthesized by selectively elaborately extending the alkyl inner side chain flanking on pyrrole motif to prepare efficient as-cast devices. As extension of chain, absorption spectra films gradually blue-shifted from A1 A5 along with slightly uplifted lowest unoccupied molecular orbital energy levels, which is conducive optimizing trade-off between short-circuit current density open-circuit voltage Moreover, a longer improves compatibility acceptor donor. The in situ technique clarifies that good will prolong assembly time assist preferential formation donor phase, where precipitates framework formed corresponding film-formation dynamics facilitate realization favorable film morphology suitable fibrillar structure, stacking, vertical phase separation, resulting an incremental fill factor A5-based Consequently, A3-based OSCs achieve top-ranked efficiency 18.29%. This work proposes ingenious strategy manipulate intermolecular interactions control process constructing high-performance

Язык: Английский

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