Advantages, challenges and molecular design of different material types used in organic solar cells

Nature Reviews Materials, Journal Year: 2023, Volume and Issue: 9(1), P. 46 - 62

Published: Dec. 15, 2023

Language: Английский

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Improved photovoltaic performance and robustness of all-polymer solar cells enabled by a polyfullerene guest acceptor

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

Published: April 22, 2023

Abstract Fullerene acceptors typically possess excellent electron-transporting properties and can work as guest components in ternary organic solar cells to enhance the charge extraction efficiencies. However, conventional fullerene small molecules suffer from undesirable segregation dimerization, thus limiting their applications cells. Herein we report use of a poly(fullerene- alt -xylene) acceptor (PFBO-C12) component enables significant efficiency increase 16.9% for binary 18.0% all-polymer Ultrafast optic optoelectronic studies unveil that PFBO-C12 facilitate hole transfer suppress recombination. Morphological investigations show blends maintain favorable morphology with high crystallinity smaller domain size. Meanwhile, introduction reduces voltage loss light stability mechanical durability flexible devices. This demonstrates introducing polyfullerenes is an effective approach achieving highly efficient good robustness.

Language: Английский

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High‐Performance Organic Solar Cells Containing Pyrido[2,3‐b]quinoxaline‐Core‐Based Small‐Molecule Acceptors with Optimized Orbit Overlap Lengths and Molecular Packing

Angewandte Chemie International Edition, Journal Year: 2023, Volume and Issue: 62(30)

Published: May 26, 2023

Abstract The central core in A‐DA 1 D‐A‐type small‐molecule acceptor (SMAs) plays an important role determining the efficiency of organic solar cells (OSCs), while principles governing efficient design SMAs remain elusive. Herein, we developed a series with pyrido[2,3‐ b ]quinoxaline (PyQx) as new electron‐deficient unit by combining cascade‐chlorination strategy, namely Py1, Py2, Py3, Py4 and Py5. introduction chlorine atoms reduces intramolecular charge transfer effects but elevates LUMO values. Density functional theory (DFT) reveals that Py2 ortho substituted PyQx Py5 two yield larger dipole moments smaller π⋅⋅⋅π stacking distances, compared other three acceptors. Moreover, shows strongest light absorption capability induced extended orbit overlap lengths more packing structures dimers. These features endow best device performance due to better molecular aggregation behaviors, suitable domain sizes exciton dissociation recombination. This study highlights significance incorporating large moments, small distances dimers into development high‐performance SMAs, providing insight for OSCs.

Language: Английский

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Tunable Donor Aggregation Dominance in a Ternary Matrix of All‐Polymer Blends with Improved Efficiency and Stability

Advanced Materials, Journal Year: 2023, Volume and Issue: 36(15)

Published: July 7, 2023

Abstract Using two structurally similar polymer acceptors in constructing high‐efficiency ternary all‐polymer solar cells is a widely acknowledged strategy; however, the focus thus far has not been on how acceptor(s) would tune aggregation of donors, and furthermore film morphology device performance (efficiency stability). Herein, it reported that matching celebrity acceptor PY‐IT donor PBQx‐TCl results enhanced H ‐ PBQx‐TCl, which can be finely tuned by controlling amount second PY‐IV. Consequently, efficiency‐optimized PY‐IV weight ratio (0.2/1.2) leads to state‐of‐the‐art power conversion efficiency 18.81%, wherein light‐illuminated operational stability also along with well‐protected thermal stability. Such enhancements stabilities attributed optimization desired glass transition temperature target active layer based comprehensive characterization. In addition being high‐power case for cells, these are successful attempt using combined toward optimal morphology, provides theoretical basis construction other types organic photovoltaics beyond cells.

Language: Английский

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Dithienoquinoxalineimide‐Based Polymer Donor Enables All‐Polymer Solar Cells Over 19 % Efficiency

Angewandte Chemie International Edition, Journal Year: 2024, Volume and Issue: 63(21)

Published: Feb. 22, 2024

All-polymer solar cells (all-PSCs) have been regarded as one of the most promising candidates for commercial applications owing to their outstanding advantages such mechanical flexibility, light weight and stable film morphology. However, compared large amount new-emerging excellent polymer acceptors, development high-performance donor lags behind. Herein, a new D-π-A type donor, namely QQ1, was developed based on dithienoquinoxalineimide (DTQI) A unit, benzodithiophene with thiophene-conjugated side chains (BDTT) D alkyl-thiophene π-bridge, respectively. QQ1 not only possesses strong dipole moment, but also shows wide band gap 1.80 eV deep HOMO energy level -5.47 eV, even without halogen substituents that are commonly indispensable donors. When blended classic acceptor PY-IT, QQ1-based all-PSC delivers an PCE 18.81 %. After introduction F-BTA3 third component, record 19.20 % obtained, highest value reported so far all-PSCs. The impressive photovoltaic performance originates from broad absorption range, reduced loss, compact π-π stacking. These results provide insight in rational design novel nonhalogenated donors further

Language: Английский

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An Isomeric Solid Additive Enables High‐Efficiency Polymer Solar Cells Developed Using a Benzo‐Difuran‐Based Donor Polymer

Advanced Materials, Journal Year: 2023, Volume and Issue: 35(26)

Published: April 12, 2023

Abstract Currently, nearly all high‐efficiency organic photovoltaic devices use donor polymers based on the benzo‐dithiophene (BDT) unit. To diversify choices of building blocks for high‐performance polymers, benzo‐difuran (BDF) units is explored, which can achieve reduced steric hindrance, stronger molecular packing, and tunable energy levels. In previous research, performance BDF‐based lagged behind those BDT‐based devices. this study, a high efficiency (18.4%) achieved using polymer donor, highest reported BDF materials to date. The enabled by (D18‐Fu) aid solid additive (2‐chloronaphthalene), isomer commonly used 1‐chloronaphthalene. These results revealed significant effect 2‐chloronaphthalene in optimizing morphology enhancing device parameters. This work not only provides new block that an comparable dominant BDT but also proposes replace widely 1‐chloronaphthalene additive.

Language: Английский

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Green-Solvent Processed Blade-Coating Organic Solar Cells with an Efficiency Approaching 19% Enabled by Alkyl-Tailored Acceptors

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

Published: Nov. 2, 2023

Abstract Power-conversion-efficiencies (PCEs) of organic solar cells (OSCs) in laboratory, normally processed by spin-coating technology with toxic halogenated solvents, have reached over 19%. However, there is usually a marked PCE drop when the blade-coating and/or green-solvents toward large-scale printing are used instead, which hampers practical development OSCs. Here, new series N -alkyl-tailored small molecule acceptors named YR-SeNF same molecular main backbone developed combining selenium-fused central-core and naphthalene-fused end-group. Thanks to -alkyl engineering, NIR-absorbing show different crystallinity, packing patterns, miscibility polymeric donor. The studies exhibit that packing, vertical distribution active layer morphologies well optimized introducing newly designed guest acceptor associated tailored chains, providing improved charge transfer dynamics stability for PM6:L8-BO:YR-SeNF-based As result, record-high approaching 19% achieved OSCs fabricated from green-solvent o -xylene high-boiling point. Notably, ternary offer robust operating under maximum-power-point tracking well-keep > 80% initial PCEs even 400 h. Our alkyl-tailored strategy provides unique approach develop high-efficiency stable OSCs, paves way industrial development.

Language: Английский

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Step-by-Step Modulation of Crystalline Features and Exciton Kinetics for 19.2% Efficiency Ortho-Xylene Processed Organic Solar Cells

Nano-Micro Letters, Journal Year: 2023, Volume and Issue: 16(1)

Published: Nov. 23, 2023

Abstract With plenty of popular and effective ternary organic solar cells (OSCs) construction strategies proposed applied, its power conversion efficiencies (PCEs) have come to a new level over 19% in single-junction devices. However, previous studies are heavily based chloroform (CF) leaving behind substantial knowledge deficiencies understanding the influence solvent choice when introducing third component. Herein, we present case where newly designed asymmetric small molecular acceptor using fluoro-methoxylated end-group modification strategy, named BTP-BO-3FO with enlarged bandgap, brings different morphological evolution performance improvement effect on host system PM6:BTP-eC9, processed by CF ortho-xylene ( o -XY). detailed analyses supported series experiments, best PCE 19.24% for green solvent-processed OSCs is found be fruit finely tuned crystalline ordering general aggregation motif, which furthermore nourishes favorable charge generation recombination behavior. Likewise, can achieved replacing spin-coating blade coating active layer deposition. This work focuses commonly met yet frequently ignored issues building blends demonstrate cutting-edge device performance, hence, will instructive other OSC works future.

Language: Английский

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

Accounts of Materials Research, Journal Year: 2023, Volume and Issue: 4(9), P. 772 - 785

Published: Aug. 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.

Language: Английский

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Oligomeric Acceptor Enables High‐Performance and Robust All‐Polymer Solar Cells with 17.4% Efficiency

Advanced Energy Materials, Journal Year: 2023, Volume and Issue: 13(20)

Published: April 6, 2023

Abstract Developing efficient and stable all‐polymer solar cells (all‐PSCs) has received increasing attention because of their mechanical robustness for flexible devices. Based on the CH‐series small molecule acceptors, a new polymer acceptor (PZC24) is reported obtains decent power conversion efficiency (PCE) 16.82% when blended with PM6. To further improve performance, an oligomeric (CH‐D1), which possesses same backbone structure as PZC24, proposed synthesized third component all‐PSC system. The creative strategy improves crystallinity molecular packing, can maintain charge transport channels all‐PSCs binary Therefore, PM6:PZC24:CH‐D1 based ternary devices exhibit impressive PCE 17.40%, among highest value all‐PSCs. Compared to PM6:PZC24, device exhibits enhanced photosoaking stability thermal stability, simultaneously. In addition, introduction does not weaken As such, display excellent 15.35%. Importantly, this shows universality in PM6:PY‐IT PM6:PY‐V‐γ improved PCEs over 17%. results provide feasible simultaneously photovoltaic herald bright future

Language: Английский

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