Influence of Donor Skeleton on Intramolecular Electron Transfer Amount for Efficient Perovskite Solar Cells

Angewandte Chemie International Edition, Год журнала: 2024, Номер 63(32)

Опубликована: Май 16, 2024

Abstract The passivation of the defects derived from rapid‐crystallization with electron‐donating molecules is always a prerequisite to obtain desirable perovskite films for efficient and stable solar cells, thus, in‐depth understanding on correlations between molecular structure capacity great importance screening passivators. Here, we introduce double‐ended amide molecule into precursor solution modulate crystallization process passivate defects. By regulating intermediate bridging skeletons alkyl, alkenyl benzene groups, results show strength highly depends spin‐state electronic that serves as an intrinsic descriptor determine intramolecular charge distribution by controlling orbital electron transfer donor segment acceptor segment. Upon careful optimization, benzene‐bridged demonstrates superior efficacy improving film quality. As physical proof‐of‐concept, carbon‐based, all‐inorganic CsPbI 2 Br cell delivers significantly increased efficiency 15.51 % remarkably improved stability. Based same principle, champion 24.20 further obtained inverted (Cs 0.05 MA FA 0.9 )Pb(I 0.93 0.07 ) 3 cell. These findings provide new fundamental insights influence modulation effective cells.

Язык: Английский

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Molecular Cross-Linking Enhances Stability of Non-Fullerene Acceptor Organic Photovoltaics

ACS Energy Letters, Год журнала: 2025, Номер 10(1), С. 541 - 551

Опубликована: Янв. 1, 2025

Understanding efficiency–durability relationships and related mitigation strategies is an important step toward the commercialization of organic photovoltaics (OPVs). Here, we report that a photoactivated 6-bridged azide cross-linker (6Bx) improves morphological stability by suppressing thermally activated diffusion (Y6) acceptor molecules in PM6:Y6 bulk-heterojunction (BHJ)-based OPVs. Cross-linked (0.05 wt % 6Bx) BHJ OPVs retain 93.4% initial power conversion efficiency upon thermal aging at 85 °C for 1680 h (T80 = 3290 h). Molecular origins enhanced are corroborated optical spectroscopy, surface imaging, 2D solid-state nuclear magnetic resonance (ssNMR), Raman scanning electron diffraction (SED) measurements, analysis thin films. The facile single-step cross-linking strategy conjugation with advanced characterization methods presented study paves way developing durable based on non-fullerene acceptors (NFAs).

Язык: Английский

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Impact of Linking‐Site on Photovoltaic Performance of Giant Molecular Acceptors Containing N‐Type Linker

Advanced Functional Materials, Год журнала: 2025, Номер unknown

Опубликована: Фев. 11, 2025

Abstract Connecting small molecule acceptors through conjugated or nonconjugated linker to form giant molecular (GMAs) represents a strategic approach enhancing the morphological stability of organic solar cells (OSCs). In this study, we employed benzothiadiazole (BT) as typical n ‐type design and synthesize two GMAs linking‐site isomerization: i‐BT‐DY o‐BT‐DY. Compared i‐BT‐DY, o‐BT‐DY exhibits enhanced crystallinity more favorable face‐on orientation but lower electron mobility. This can be well explained by theoretical calculations, demonstrates delocalized LUMO distribution significantly stronger intramolecular super‐exchange coupling (43.7 meV versus 22.2 for o‐BT‐DY). Additionally, also red‐shifted absorption. Combining these attributes, PM6: blend achieved an impressive power conversion efficiency (PCE) 18.86%. The PCE further increased 19.49% in ternary blend. As expected, OSCs based on both exhibit exceptional long‐term photostability (T85% >1000 hours). work deepens our understanding how linkers at different linking sites influence performance GMAs, concluding that interaction, rather than intermolecular, are primary factor affecting charge transport acceptors. it highlights potential components OSCs.

Язык: Английский

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Molecular Design of Dimeric Acceptor Enables Binary Organic Solar Cells with 19.78% Efficiency and Enhanced Stability

Advanced Materials, Год журнала: 2025, Номер unknown

Опубликована: Март 3, 2025

Abstract The development of organic solar cells (OSCs) with high efficiency and stability is highly desirable to facilitate its commercial applications. Although dimeric acceptors distinctive advantages have been widely studied, high‐performance binary OSCs based on such molecules rarely achieved. In this work, a new acceptor (DY‐FL) constructed by simultaneously optimizing the linking sites units, as well building blocks. Thanks effective molecular design, DY‐FL provides improved stacking for fibrous morphology favorable exciton/charge dynamics. Consequently, DY‐FL‐based render superior power conversion (PCE) 19.78%, representing record‐breaking acceptors. Importantly, devices display significantly enhanced operational under external stimuli light heat, in comparison their small molecule (Y‐F)‐based counterpart. These findings highlight significance blocks modes, providing insight into design strategy state‐of‐the‐art OSCs.

Язык: Английский

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Binary All‐polymer Solar Cells with a Perhalogenated‐Thiophene‐Based Solid Additive Surpass 18 % Efficiency

Angewandte Chemie, Год журнала: 2024, Номер 136(9)

Опубликована: Янв. 3, 2024

Abstract Morphological control of all‐polymer blends is quintessential yet challenging in fabricating high‐performance organic solar cells. Recently, solid additives (SAs) have been approved to be capable tuning the morphology polymer: small‐molecule improving performance and stability devices. Herein, three perhalogenated thiophenes, which are 3,4‐dibromo‐2,5‐diiodothiophene (SA‐T1), 2,5‐dibromo‐3,4‐diiodothiophene (SA‐T2), 2,3‐dibromo‐4,5‐diiodothiophene (SA‐T3), were adopted as SAs optimize cells (APSCs). For blend PM6 PY‐IT, benefitting from intermolecular interactions between thiophenes polymers, molecular packing properties could finely regulated after introducing these SAs. In situ UV/Vis measurement revealed that assist morphological character evolution blend, leading their optimal morphologies. Compared as‐cast device : all SA‐treated binary devices displayed enhanced power conversion efficiencies 17.4–18.3 % with obviously elevated short‐circuit current densities fill factors. To our knowledge, PCE 18.3 for SA‐T1‐treated ranks highest among APSCs date. Meanwhile, universality SA‐T1 other demonstrated unanimously improved performance. This work provide a new pathway realizing APSCs.

Язык: Английский

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