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

Joule, Год журнала: 2024, Номер 8(3), С. 835 - 851

Опубликована: Янв. 30, 2024

Язык: 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, Год журнала: 2022, Номер 61(41)

Опубликована: Июль 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.

Язык: Английский

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

Nature Communications, Год журнала: 2023, Номер 14(1)

Опубликована: Авг. 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.

Язык: Английский

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Peripheral halogenation engineering controls molecular stacking to enable highly efficient organic solar cells

Energy & Environmental Science, Год журнала: 2022, Номер 15(8), С. 3519 - 3533

Опубликована: Янв. 1, 2022

The diverse molecular stacking tuned by peripheral halogens in non-fullerene acceptors (NFAs) significantly affects the physicochemical properties, film morphologies and thus power conversion efficiencies (PCEs) of organic solar cells (OSCs).

Язык: Английский

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3D acceptors with multiple A–D–A architectures for highly efficient organic solar cells

Energy & Environmental Science, Год журнала: 2023, Номер 16(4), С. 1773 - 1782

Опубликована: Янв. 1, 2023

Efficient 3D NFAs through central unit connection blaze a new trail in further molecular structural optimization of state-of-the-art NFAs.

Язык: Английский

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Oligomerized Fused‐Ring Electron Acceptors for Efficient and Stable Organic Solar Cells

Angewandte Chemie International Edition, Год журнала: 2023, Номер 62(46)

Опубликована: Июль 12, 2023

Abstract Organic solar cells (OSCs) have attracted wide research attention in the past decades. Very recently, oligomerized fused‐ring electron acceptors (OFREAs) emerged as a promising alternative to small‐molecular/polymeric acceptor‐based OSCs due their unique advantages such well‐defined structures, batch reproducibility, good film formation, low diffusion coefficient, and excellent stability. So far, rapid advances been made development of OFREAs consisting directly/rigidly/flexibly linked oligomers fused ones. In this Minireview, we systematically summarized recent progress OFREAs, including structural diversity, synthesis approach, molecular conformation packing, long‐term Finally, conclude with future perspectives on challenges be addressed potential directions. We believe that Minireview will encourage novel for OSC applications.

Язык: Английский

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Electronic Configuration Tuning of Centrally Extended Non‐Fullerene Acceptors Enabling Organic Solar Cells with Efficiency Approaching 19 %

Angewandte Chemie International Edition, Год журнала: 2023, Номер 62(42)

Опубликована: Авг. 26, 2023

In the molecular optimizations of non-fullerene acceptors (NFAs), extending central core can tune energy levels, reduce nonradiative loss, enhance intramolecular (donor-acceptor and acceptor-acceptor) packing, facilitate charge transport, improve device performance. this study, a new strategy was employed to synthesize featuring conjugation-extended electron-deficient cores. Among these, acceptor CH-BBQ, embedded with benzobisthiadiazole, exhibited an optimal fibrillar network morphology, enhanced crystallinity, improved generation/transport in blend films, leading power conversion efficiency 18.94 % for CH-BBQ-based ternary organic solar cells (OSCs; 18.19 binary OSCs) owing its delicate structure design electronic configuration tuning. Both experimental theoretical approaches were used systematically investigate influence on properties The modulation paves pathway engineering NFAs, propelling relevant research forward.

Язык: Английский

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Complete Peripheral Fluorination of the Small‐Molecule Acceptor in Organic Solar Cells Yields Efficiency over 19 %

Angewandte Chemie International Edition, Год журнала: 2023, Номер 62(44)

Опубликована: Сен. 14, 2023

Due to the intrinsically flexible molecular skeletons and loose aggregations, organic semiconductors, like small acceptors (SMAs) in solar cells (OSCs), greatly suffer from larger structural/packing disorders weaker intermolecular interactions comparing their inorganic counterparts, further leading hindered exciton diffusion/dissociation charge carrier migration resulting OSCs. To overcome this challenge, complete peripheral fluorination was performed on basis of a two-dimensional (2D) conjugation extended platform CH-series SMAs, rendering an acceptor CH8F with eight fluorine atoms surrounding backbone. Benefitting broad 2D backbone, more importantly, strengthened fluorine-induced secondary interactions, its D18 blends afford much enhanced ordered packings accompanying enlarged dielectric constants, reduced binding energies obvious fibrillary networks CH6F controls. Consequently, D18:CH8F-based OSCs reached excellent efficiency 18.80 %, better than that 17.91 % for CH6F-based ones. More excitingly, by employing D18-Cl possesses highly similar structure as third component, highest 19.28 SMAs-based has been achieved so far. Our work demonstrates dramatical structural multiformity meanwhile, high potential constructing record-breaking through fine-tuning.

Язык: Английский

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Highly Efficient and Stable FA‐Based Quasi‐2D Ruddlesden–Popper Perovskite Solar Cells by the Incorporation of β‐Fluorophenylethanamine Cations

Advanced Materials, Год журнала: 2023, Номер 35(17)

Опубликована: Фев. 6, 2023

2D Ruddlesden-Popper (2D RP) perovskite, with attractive environmental and structural stability, has shown great application in perovskite solar cells (PSCs). However, the relatively inferior photovoltaic efficiencies of PSCs limit their further application. To address this issue, β-​fluorophenylethanamine (β-​FPEA) as a novel spacer cation is designed employed to develop stable efficient quasi-2D RP PSCs. The strong dipole moment β-​FPEA enhances interactions between cations [PbI6 ]4- octahedra, thus improving charge dissociation perovskite. Additionally, introduction optimizes energy level alignment, improves crystallinity, stabilizes both mixed phase a-FAPbI3 film, prolongs carrier diffusion length, increases lifetime decreases trap density. By incorporating β-​FPEA, exhibit power conversion efficiency (PCE) 16.77% (vs phenylethylammonium (PEA)-based 12.81%) on PEDOT:PSS substrate achieve champion PCE 19.11% PTAA substrate. It worth noting that unencapsulated β-​FPEA-based considerably improved thermal moisture stability. These findings provide an effective strategy for developing high-performance

Язык: Английский

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Two-Dimensional Conjugation Extended CH-Series Acceptors with a Distinctive A–D–A Character

Accounts of Materials Research, Год журнала: 2023, Номер 4(9), С. 772 - 785

Опубликована: Авг. 2, 2023

ConspectusAs one of the most important indicators for evaluating photovoltaic devices, power conversion efficiencies (PCEs) first-class organic solar cells (OSCs) have reached level ∼20%, but they still lag far behind that over 25% their inorganic counterparts. With similar if not better fill factor and short-circuit current, this wide gap PCEs should be fundamentally attributed to greatly larger nonradiative energy losses in OSCs, which are usually above 0.2 eV OSCs only 0.03–0.04 high-performance cells. Note stubbornly severe recombination is associated with multiple characteristics light-harvesting molecules, such as intrinsically large exciton binding energies small relative dielectric constants, defective intermolecular packing networks, or more crystal defects caused by flexibility molecular skeletons, nonideal nanoscale film morphologies, so on. All factors require rational design molecules carried out at single molecule also aggregation levels further dramatic improvement PCE achieved OSCs.In Account, we will first expound unique merits acceptor–donor–acceptor (A–D–A) type materials frontier orbital distribution, tuning, packings, meanwhile revealing dominant role A–D–A facilitating charge transfer/transport, suppressing loss, improving performance eventually. In light conspicuous superiority a convincing conclusion can made exploration novel crucially shrink between Second, our recent studies really exciting platform (CH-series) discussed comprehensively, involving various nonfullerene acceptors (NFAs) molecular, dimer-like, polymerized architectures. distinctive feature CH-series NFAs two-dimensional (2D) conjugation extension, especially central units. Therefore, favorable effects 2D extension these on fundamental physicochemical properties, modes, blended parameters, resulting fully discussed. Abiding unveiled rules NFAs, highest approaching 20% has been based molecules. The evolution path previous traditional PCBM, ITIC, Y6, etc. could lesson; very likely offer great capable achieving record-breaking along much decreased losses, considering structural modification possibilities. Finally, despite rapidly surging there several insurmountable hurdles when attempting break through bottlenecks existing OSCs. propose some perspectives conducted may conquer challenge too thus boost toward commercial applications further.

Язык: Английский

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