Single-layered organic photovoltaics with double cascading charge transport pathways: 18% efficiencies

Nature Communications, Год журнала: 2021, Номер 12(1)

Опубликована: Янв. 12, 2021

Abstract The chemical structure of donors and acceptors limit the power conversion efficiencies achievable with active layers binary donor-acceptor mixtures. Here, using quaternary blends, double cascading energy level alignment in bulk heterojunction organic photovoltaic are realized, enabling efficient carrier splitting transport. Numerous avenues to optimize light absorption, transport, charge-transfer state levels opened by constitution components. Record-breaking PCEs 18.07% achieved where, electronic morphology optimization, simultaneous improvements open-circuit voltage, short-circuit current fill factor occur. donor acceptor structures afford control over levels, manipulation hole-transfer rates, non-radiative recombination losses.

Язык: Английский

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Efficient Organic Solar Cell with 16.88% Efficiency Enabled by Refined Acceptor Crystallization and Morphology with Improved Charge Transfer and Transport Properties

Advanced Energy Materials, Год журнала: 2020, Номер 10(18)

Опубликована: Март 20, 2020

Abstract Single‐layered organic solar cells (OSCs) using nonfullerene acceptors have reached 16% efficiency. Such a breakthrough has inspired new sparks for the development of next generation OSC materials. In addition to optimization electronic structure, it is important investigate essential solid‐state structure that guides high efficiency bulk heterojunction blends, which provides insight in understanding how pair an efficient donor–acceptor mixture and refine film morphology. this study, thorough analysis executed reveal morphology details, results demonstrate Y6 can form unique 2D packing with polymer‐like conjugated backbone oriented normal substrate, controlled by processing solvent thermal annealing conditions. improved carrier transport ultrafast hole electron transfer, leading device performance, best optimized shows power conversion 16.88% (16.4% certified). This work reveals importance mechanism affects performance. A full set analytical methods conditions are achieve from materials design optimization, will be useful future technology development.

Язык: Английский

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Recent progress in organic solar cells (Part I material science)

Science China Chemistry, Год журнала: 2021, Номер 65(2), С. 224 - 268

Опубликована: Дек. 27, 2021

Язык: Английский

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A History and Perspective of Non‐Fullerene Electron Acceptors for Organic Solar Cells

Advanced Energy Materials, Год журнала: 2021, Номер 11(15)

Опубликована: Янв. 14, 2021

Abstract Organic solar cells are composed of electron donating and accepting organic semiconductors. Whilst a significant palette donors has been developed over three decades, until recently only small number acceptors have proven capable delivering high power conversion efficiencies. In particular the fullerenes dominated landscape. this perspective, emergence family materials–the non‐fullerene (NFAs) is described. These delivered discontinuous advance in cell efficiencies, with milestone 20% now sight. Intensive international efforts synthetic chemistry established clear design rules for molecular engineering enabling an ever‐expanding efficiency candidates. However, these materials challenge accepted wisdom how work force new thinking areas such as morphology, charge generation recombination. This perspective provides historical context development NFAs, also addresses current plus considers important manufacturability criteria. There no doubt that NFAs propelled technology to efficiencies necessary viable commercial technology–but far can they be pushed, will deliver on equally metrics stability?

Язык: Английский

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Polymerized Small‐Molecule Acceptors for High‐Performance All‐Polymer Solar Cells

Angewandte Chemie International Edition, Год журнала: 2020, Номер 60(9), С. 4422 - 4433

Опубликована: Авг. 28, 2020

Abstract All‐polymer solar cells (all‐PSCs) have drawn tremendous research interest in recent years, due to their inherent advantages of good film formation, stable morphology, and mechanical flexibility. The most representative widely used n ‐CP acceptor was the naphthalene diimide based D‐A copolymer N2200 before 2017, power conversion efficiency (PCE) all‐PSCs on reached over 8% 2016. However, low absorption coefficient near‐infrared (NIR) region limits further increase its PCE. In we proposed a strategy polymerizing small‐molecule acceptors (SMAs) construct new‐generation polymer acceptors. polymerized SMAs (PSMAs) possess band gap strong NIR region, which attracted great attention drove PCE 15% recently. this Minireview explain design strategies molecular structure PSMAs describe progress. Finally, current challenges future prospects are analyzed discussed.

Язык: Английский

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Precisely Controlling the Position of Bromine on the End Group Enables Well‐Regular Polymer Acceptors for All‐Polymer Solar Cells with Efficiencies over 15%

Advanced Materials, Год журнала: 2020, Номер 32(48)

Опубликована: Окт. 29, 2020

Recent advances in the development of polymerized A-D-A-type small-molecule acceptors (SMAs) have promoted power conversion efficiency (PCE) all-polymer solar cells (all-PSCs) over 13%. However, monomer an SMA typically consists a mixture three isomers due to regio-isomeric brominated end groups (IC-Br(in) and IC-Br(out)). In this work, two isomeric are successfully separated, regioisomeric issue is solved, polymer acceptors, named PY-IT, PY-OT, PY-IOT, developed, where PY-IOT random terpolymer with same ratio acceptors. Interestingly, from absorption edge gradually redshifts electron mobility progressively increases. Theory calculation indicates that LUMOs distributed on entire molecular backbone contributing enhanced transport. Consequently, PM6:PY-IT system achieves excellent PCE 15.05%, significantly higher than those for PY-OT (10.04%) (12.12%). Morphological device characterization reveals highest PY-IT-based fruit absorption, more balanced charge transport, favorable morphology. This work demonstrates site polymerization SMAs strongly affects performance, offering insights into efficient all-PSCs.

Язык: Английский

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14.4% efficiency all-polymer solar cell with broad absorption and low energy loss enabled by a novel polymer acceptor

Nano Energy, Год журнала: 2020, Номер 72, С. 104718 - 104718

Опубликована: Март 20, 2020

Язык: Английский

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Mechanically Robust All-Polymer Solar Cells from Narrow Band Gap Acceptors with Hetero-Bridging Atoms

Joule, Год журнала: 2020, Номер 4(3), С. 658 - 672

Опубликована: Фев. 17, 2020

Язык: Английский

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All-small-molecule organic solar cells with over 14% efficiency by optimizing hierarchical morphologies

Nature Communications, Год журнала: 2019, Номер 10(1)

Опубликована: Ноя. 26, 2019

The high efficiency all-small-molecule organic solar cells (OSCs) normally require optimized morphology in their bulk heterojunction active layers. Herein, a small-molecule donor is designed and synthesized, single-crystal structural analyses reveal its explicit molecular planarity compact intermolecular packing. A promising narrow bandgap with absorption edge of more than 930 nm along our home-designed small molecule selected as electron acceptors. To the best knowledge, binary OSCs achieve highest 14.34% by optimizing hierarchical morphologies, which or acceptor rich domains size up to ca. 70 nm, crystals tens nanometers, together donor-acceptor blending, are proved coexisting large domain. All-small-molecule photovoltaic system shows for performance OSCs, study likely lead insights relations between structure performance.

Язык: Английский

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Optimized active layer morphology toward efficient and polymer batch insensitive organic solar cells

Nature Communications, Год журнала: 2020, Номер 11(1)

Опубликована: Июнь 5, 2020

Abstract Morphology control in laboratory and industry setting remains as a major challenge for organic solar cells (OSCs) due to the difference film-drying kinetics between spin coating printing process. A two-step sequential deposition method is developed active layer morphology. conjugated polymer that self-assembles into well-defined fibril structure used first layer, then non-fullerene acceptor introduced mesh second form an optimal benefit of combined network morphology properties was high efficiency 16.5% (certified 16.1%) achieved. The preformed sequentially deposited robust insensitive batches, solving notorious issue OSCs. Such progress demonstrates utilization networks process promising approach towards fabrication high-efficiency

Язык: Английский

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