Machine learning and molecular dynamics simulation-assisted evolutionary design and discovery pipeline to screen efficient small molecule acceptors for PTB7-Th-based organic solar cells with over 15% efficiency

Journal of Materials Chemistry A, Journal Year: 2022, Volume and Issue: 10(8), P. 4170 - 4180

Published: Jan. 1, 2022

A multi-stage machine learning and molecular dynamics simulation-assisted pipeline is introduced for the time- cost-efficient design screening of small molecule acceptors organic solar cells.

Language: Английский

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19.7% efficiency binary organic solar cells achieved by selective core fluorination of nonfullerene electron acceptors

Joule, Journal Year: 2024, Volume and Issue: 8(3), P. 835 - 851

Published: Jan. 30, 2024

Language: Английский

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Organic Solar Cells with Over 19% Efficiency Enabled by a 2D‐Conjugated Non‐Fullerene Acceptor Featuring Favorable Electronic and Aggregation Structures

Advanced Materials, Journal Year: 2023, Volume and Issue: 35(32)

Published: May 27, 2023

The π-expansion of non-fullerene acceptors is a promising method for boosting the organic photovoltaic performance by allowing fine-tuning electronic structures and molecular packing. In this work, highly efficient solar cells (OSCs) are fabricated using 2D strategy to design new acceptors. Compared with quinoxaline-fused cores AQx-16, π-expanded phenazine-fused AQx-18 induce more ordered compact packing between adjacent molecules, affording an optimized morphology rational phase separation in blend film. This facilitates exciton dissociation inhibited charge recombination. Consequently, power conversion efficiency (PCE) 18.2% simultaneously increasing Voc , Jsc fill factor achieved AQx-18-based binary OSCs. Significantly, ternary devices via two-in-one alloy acceptor exhibit superior PCE 19.1%, one highest values ever reported OSCs, along high 0.928 V. These results indicate importance delicate regulation crystalline behaviors achieve performance, aimed at significantly promoting further development

Language: Английский

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Machine Learning for Organic Photovoltaic Polymers: A Minireview

Chinese Journal of Polymer Science, Journal Year: 2022, Volume and Issue: 40(8), P. 870 - 876

Published: June 21, 2022

Language: Английский

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Central Unit Fluorination of Non‐Fullerene Acceptors Enables Highly Efficient Organic Solar Cells with Over 18 % Efficiency

Angewandte Chemie International Edition, Journal Year: 2022, Volume and Issue: 61(41)

Published: July 27, 2022

Halogenation of terminal acceptors has been shown to give dramatic improvements in power conversion efficiencies (PCEs) organic solar cells (OSCs). Similar significant results could be expected from the halogenation central units state-of-the-art Y-series acceptors. Herein, a pair acceptors, termed CH6 and CH4, featuring conjugation-extended phenazine unit with without fluorination, have synthesized. The fluorinated enhanced molecular interactions crystallinity, superior fibrillar network morphology improved charge generation transport blend films, thus affording higher PCE 18.33 % for CH6-based binary OSCs compared 16.49 non-fluorinated CH4. new site offers further opportunities structural optimization molecules afford better-performed reveals effectiveness fluorination on units.

Language: Английский

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A rare case of brominated small molecule acceptors for high-efficiency organic solar cells

Nature Communications, Journal Year: 2023, Volume and Issue: 14(1)

Published: Aug. 5, 2023

Abstract Given that bromine possesses similar properties but extra merits of easily synthesizing and polarizing comparing to homomorphic fluorine chlorine, it is quite surprising very rare high-performance brominated small molecule acceptors have been reported. This may be caused by undesirable film morphologies stemming from relatively larger steric hindrance excessive crystallinity bromides. To maximize the advantages bromides while circumventing weaknesses, three (CH20, CH21 CH22) are constructed with stepwise brominating on central units rather than conventional end groups, thus enhancing intermolecular packing, dielectric constant them without damaging favorable packing through groups. Consequently, PM6:CH22-based binary organic solar cells render highest efficiency 19.06% for acceptors, more excitingly, a record-breaking 15.70% when further thickening active layers ~500 nm. By exhibiting such acceptor, our work highlights great potential achieving delicately brominating.

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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Controlling Morphology and Voltage Loss with Ternary Strategy Triggers Efficient All-Small-Molecule Organic Solar Cells

ACS Energy Letters, Journal Year: 2023, Volume and Issue: 8(2), P. 1058 - 1067

Published: Jan. 23, 2023

Herein, an emerging acceptor L8-BO as the third component was combined with B1:BO-4Cl system for constructing efficient ternary all-small-molecule organic solar cells (ASM-OSCs). Theoretical, morphological, and crystallographic studies reveal that BO-4Cl possess good compatibility, resulting in alloy-like state formation of two acceptors blends. The synergistic effect is conducive to forming favorable phase separation molecular stacking promoting charge splitting extraction, which contributes simultaneously boosting short-circuit current density fill factor. Furthermore, higher lowest unoccupied orbital energy level assist ASM-OSCs achieving lower voltage loss respect binary devices. optimal 20 wt % deliver a top-level efficiency 17.10%. This work demonstrates not only morphology but also small matrix can be well-manipulated by employing strategy.

Language: Английский

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Non-covalent interactions (NCIs) in π-conjugated functional materials: advances and perspectives

Chemical Society Reviews, Journal Year: 2023, Volume and Issue: 52(2), P. 454 - 472

Published: Jan. 1, 2023

We describe the role of non-covalent intermolecular interactions in design π-conjugated functional materials. highlight opto-electronic applications these materials related to their structural and photophysical properties.

Language: Английский

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Regioisomer‐Free Difluoro‐Monochloro Terminal‐based Hexa‐Halogenated Acceptor with Optimized Crystal Packing for Efficient Binary Organic Solar Cells

Angewandte Chemie International Edition, Journal Year: 2022, Volume and Issue: 61(46)

Published: Sept. 2, 2022

Herein, we synthesized new hetero-halogenated end groups with well-determined fluorinated and chlorinated substitutions (o-FCl-IC FClF-IC), regioisomer-free small molecular acceptors (SMAs) Y-Cl, Y-FCl, Y-FClF distinct terminals, respectively. The single-crystal structures theoretical calculations indicate that exhibits more compact three-dimensional network packing significant π-π electronic coupling compared to Y-FCl. From Y-Cl Y-FCl Y-FClF, the neat films exhibit a narrower optical band gap gradually enhanced electron mobility crystallinity. PM6 : blend film strongest crystallinity preferential face-on packing, desirable fibrous morphology suitable phase segregation, highest balanced charge mobilities among three films. Overall, organic solar cells (OSCs) deliver remarkable efficiency of 17.65 %, outperforming which is best PCE for reported hetero-halogens-based SMAs in binary OSCs. Our results demonstrate difluoro-monochloro hetero-terminal superior regio-regular unit enhancing intermolecular crystal photovoltaic performance SMAs.

Language: Английский

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