Binary Organic Solar Cells Breaking 19% via Manipulating the Vertical Component Distribution

Advanced Materials, Journal Year: 2022, Volume and Issue: 34(33)

Published: June 24, 2022

The variation of the vertical component distribution can significantly influence photovoltaic performance organic solar cells (OSCs), mainly due to its impact on exciton dissociation and charge-carrier transport recombination. Herein, binary devices are fabricated via sequential deposition (SD) D18 L8-BO materials in a two-step process. Upon independently regulating spin-coating speeds each layer deposition, optimal SD device shows record power conversion efficiency (PCE) 19.05% for single-junction OSCs, much higher than that corresponding blend casting (BC) (18.14%). Impressively, this strategy presents excellent universality boosting devices, exemplified by several nonfullerene acceptor systems. mechanism studies reveal with preferred components possesses high crystallinity, efficient splitting, low energy loss, balanced charge transport, resulting all-around enhancement performances. This work provides valuable approach high-efficiency shedding light understanding relationship between distribution.

Language: Английский

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Realizing 19.05% Efficiency Polymer Solar Cells by Progressively Improving Charge Extraction and Suppressing Charge Recombination

Advanced Materials, Journal Year: 2022, Volume and Issue: 34(13)

Published: Jan. 26, 2022

Improving charge extraction and suppressing recombination are critically important to minimize the loss of absorbed photons improve device performance polymer solar cells (PSCs). In this work, highly efficient PSCs demonstrated by progressively improving through combination side-chain engineering new nonfullerene acceptors (NFAs), adopting ternary blends, introducing volatilizable solid additives. The 2D side chains on BTP-Th induce a certain steric hindrance for molecular packing phase separation, which is mitigated fluorination BTP-FTh. Moreover, two crystalline molecules as second acceptor additive, respectively, into BTP-FTh-based host blend, crystallinity significantly improved blend morphology finely optimized. As expected, enhanced suppressed realized, contributing largely fill factor (FF) resultant devices. Accompanied open-circuit voltage (Voc ) short-circuit current density (Jsc ), record high power conversion efficiency (PCE) 19.05% realized finally.

Language: Английский

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Fibrillization of Non‐Fullerene Acceptors Enables 19% Efficiency Pseudo‐Bulk Heterojunction Organic Solar Cells

Advanced Materials, Journal Year: 2022, Volume and Issue: 35(6)

Published: Nov. 24, 2022

The structural order and aggregation of non-fullerene acceptors (NFA) are critical toward light absorption, phase separation, charge transport properties their photovoltaic blends with electron donors, determine the power conversion efficiency (PCE) corresponding organic solar cells (OSCs). In this work, fibrillization small molecular NFA L8-BO assistance fused-ring solvent additive 1-fluoronaphthalene (FN) to substantially improve device PCE is demonstrated. Molecular dynamics simulations show that FN attaches backbone as bridge enhance intermolecular packing , inducing 1D self-assembly into fine fibrils a compact polycrystal structure. incorporated pseudo-bulk heterojunction (P-BHJ) active layer D18 donor, enhanced transport, collection properties, leading from 16.0% an unprecedented 19.0% in D18/L8-BO binary P-BHJ OSC, featuring high fill factor 80%. This work demonstrates strategy for fibrillating NFAs performance OSCs.

Language: Английский

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Recent Progress of Y6‐Derived Asymmetric Fused Ring Electron Acceptors

Advanced Functional Materials, Journal Year: 2022, Volume and Issue: 32(35)

Published: July 5, 2022

Abstract Symmetric conjugated molecules can be broken through suitable synthetic strategies to construct novel asymmetric molecules, which largely broaden the material library. In field of organic solar cells, fused‐ring electron acceptors (FREAs) with A‐DA'D‐A type backbone structure have attracted much attention and enabled power conversion efficiencies (PCE) exceeding 18%. Among them, Y6 is one most classic FREAs that derive many symmetric exhibit unique optoelectronic properties. Thus, in this review, focus on recent progress Y6‐derived containing a dipyrrolobenzothiadiazole segment, classified as following three categories: end group, central core side chain. The relationship molecular structure, properties, device performance discussed detail. Finally, future design directions challenges faced by kind photovoltaic materials are given.

Language: Английский

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19.10% Efficiency and 80.5% Fill Factor Layer‐by‐Layer Organic Solar Cells Realized by 4‐Bis(2‐Thienyl)Pyrrole‐2,5‐Dione Based Polymer Additives for Inducing Vertical Segregation Morphology

Advanced Materials, Journal Year: 2022, Volume and Issue: 35(6)

Published: Nov. 22, 2022

The morphology plays a key role in determining the charge generation and collection process, thus impacting performances of organic solar cells (OSCs). limited selection pool additives to optimize OSCs, especially for emerging layer-by-layer (LbL) impeding improvements photovoltaic performances. Herein, new method using conjugated polymers as improving LbL-OSCs is reported. Four PH, PS, PF, PCl are developed with different side chains. These exhibit poor donor materials BHJ devices, due unsuitable energy level alignment unfavorable molecular interactions. By contrast, they can be served efficient PM6 fibril matrix facilitating penetration BTP-eC9 forming an intertwined D/A bicontinuous network vertical segregation. Such optimized by chain engineering, which enables progressive improvement separation collection. As result, adding small amount additive, contributes champion PCE 19.10% high FF 80.5%.

Language: Английский

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Isogenous Asymmetric–Symmetric Acceptors Enable Efficient Ternary Organic Solar Cells with Thin and 300 nm Thick Active Layers Simultaneously

Advanced Functional Materials, Journal Year: 2022, Volume and Issue: 32(26)

Published: March 23, 2022

Abstract Integrating desirable light absorption, energy levels, and morphology in one matrix is always the aspiration to construct high‐performance organic solar cells (OSCs). Herein, an asymmetric acceptor Y6‐1O incorporated into binary blends of Y7‐BO donor PM6 prepare ternary OSCs. Two isogenous asymmetric–symmetric acceptors with similar chemical skeletons tend form alloy‐like state due their good compatibility, which contributes optimizing for efficient charge generation extraction. The complementary absorption two helps improve photon harvesting blends, higher lowest unoccupied molecular orbital (LUMO) level offers chance uplift mixed LUMO levels acceptors. Combining aforesaid benefits, OSCs 10 wt% produce a top‐ranked power conversion efficiency (PCE) 18.11% simultaneously elevated short‐circuit current density, open‐circuit voltage, fill factor comparison Y7‐BO‐based devices. Furthermore, optimized ≈300 nm active layers obtain champion PCE 16.61%, highest value thick‐film devices reported so far. This work puts forward avenue further boosting performance but different structures.

Language: Английский

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Solid Additive-Assisted Layer-by-Layer Processing for 19% Efficiency Binary Organic Solar Cells

Nano-Micro Letters, Journal Year: 2023, Volume and Issue: 15(1)

Published: April 10, 2023

Morphology is of great significance to the performance organic solar cells (OSCs), since appropriate morphology could not only promote exciton dissociation, but also reduce charge recombination. In this work, we have developed a solid additive-assisted layer-by-layer (SAA-LBL) processing fabricate high-efficiency OSCs. By adding additive fatty acid (FA) into polymer donor PM6 solution, controllable pre-phase separation forms between and FA. This intermixed facilitates diffusion acceptor Y6 during LBL processing, due good miscibility fast-solvation FA with chloroform solution dripping. Interestingly, results in desired refined phase-separated domain vertical phase-separation structure better balance transport /collection dissociation. Consequently, binary single junction OSCs based on PM6:Y6 blend reach champion power conversion efficiency (PCE) 18.16% SAA-LBL which can be generally applicable diverse systems, e.g., PM6:L8-BO-based devices thick-film devices. The efficacy confirmed PM6:L8-BO, where record PCEs 19.02% 16.44% are realized for 100 250 nm active layers, respectively. work provides simple effective way control demonstrates promising methodology boosting industrial manufacturing

Language: Английский

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Volatile Solid Additive‐Assisted Sequential Deposition Enables 18.42% Efficiency in Organic Solar Cells

Advanced Science, Journal Year: 2022, Volume and Issue: 9(9)

Published: Jan. 24, 2022

Morphology optimization of active layer plays a critical role in improving the performance organic solar cells (OSCs). In this work, volatile solid additive-assisted sequential deposition (SD) strategy is reported to regulate molecular order and phase separation state. The OSC adopts polymer donor D18-Cl acceptor N3 as layer, well 1,4-diiodobenzene (DIB) additive. Compared D18-Cl:N3 (one-time mixture) D18-Cl/N3 platforms, D18-Cl/N3(DIB) device based on DIB-assisted SD method exhibits finer with greatly enhanced crystallinity. optimal morphology delivers superior charge transport extraction, offering champion power conversion efficiency 18.42% significantly short-circuit current density (J

Language: Английский

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Over 17.4% Efficiency of Layer‐by‐Layer All‐Polymer Solar Cells by Improving Exciton Utilization in Acceptor Layer

Advanced Functional Materials, Journal Year: 2023, Volume and Issue: 33(28)

Published: March 27, 2023

Abstract Layer‐by‐layer all‐polymer solar cells (LbL all‐PSCs) are prepared with PM6 and PY‐IT by using sequential spin coating method. The exciton dissociation efficiency in acceptor layer near electrode is rather low due to the limited diffuse distance impossible energy transfer from narrow bandgap wide donor. In this study, less incorporated into enhance electrode. A power conversion (PCE) of 17.45% achieved LbL all‐PSCs incorporating 10 wt% layer, which much larger than 16.04% PCE PM6/PY‐IT‐based all‐PSCs. Over 8% enhancement can be realized attributed enhanced utilization layers confirmed quenched photoluminescence (PL) emission PY‐IT:PM6 films. Meanwhile, charge transport optimized PM6, as molecular arrangement. This study indicates that strategy donor has great potential fabricating efficient improving

Language: Английский

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A Top‐Down Strategy to Engineer ActiveLayer Morphology for Highly Efficient and Stable All‐Polymer Solar Cells

Advanced Materials, Journal Year: 2022, Volume and Issue: 34(33)

Published: June 24, 2022

A major challenge hindering the further development of all-polymer solar cells (all-PSCs) employing polymerized small-molecule acceptors is relatively low fill factor (FF) due to difficulty in controlling active-layer morphology. The issues typically arise from oversized phase separation resulting thermodynamically unfavorable mixing between two macromolecular species, and disordered molecular orientation/packing highly anisotropic polymer chains. Herein, a facile top-down strategy engineer morphology blends developed by leveraging layer-by-layer (LBL) deposition. Optimal intermixing components can be achieved two-step process tuning bottom-layer swelling during top-layer Consequently, both bottom layer ordering top optimized with suitable processing solvent. favorable gradient vertical composition distribution for efficient charge transport extraction therefore realized, affording high all-PSC efficiency 17.0% FF 76.1%. derived devices also possess excellent long-term thermal stability retain >90% their initial efficiencies after being annealed at 65 °C 1300 h. These results validate distinct advantages an LBL protocol fabricate high-performance all-PSCs.

Language: Английский

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