Adding a Third Component with Reduced Miscibility and Higher LUMO Level Enables Efficient Ternary Organic Solar Cells

ACS Energy Letters, Journal Year: 2020, Volume and Issue: 5(8), P. 2711 - 2720

Published: Aug. 3, 2020

It is widely known that the miscibility between donor and acceptor a crucial factor affects morphology thus device performance of nonfullerene organic solar cells (OSCs). In this Letter, we show incorporating third component with lower higher lowest unoccupied molecular orbital (LUMO) level into state-of-the-art PM6:Y6 system can significantly enhance devices. The best results ternary devices are achieved by adding small named ITCPTC (∼5% w/w), which improves power conversion efficiency (PCE) host from 16.44% to 17.42%. LUMO increases open-circuit voltage (VOC), while low enlarges domains leads improved short-circuit current density (JSC) fill (FF). efficacy strategy supported using other components including an asymmetric molecule (N7IT) polymer (PF2-DTC), play same role as boost PCEs 16.96% 17.04%, respectively. Our approach be potentially applied wide range OSC material systems should facilitate development field.

Language: Английский

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Fine-tuning of side-chain orientations on nonfullerene acceptors enables organic solar cells with 17.7% efficiency

Energy & Environmental Science, Journal Year: 2021, Volume and Issue: 14(6), P. 3469 - 3479

Published: Jan. 1, 2021

Regulating side-chain orientations of Y-series NFAs is a promising strategy to achieve favorable morphology, and high charge mobility solar cell performances, which enables high-performance devices with efficiency approaching 18%.

Language: Английский

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Low Band Gap Conjugated Semiconducting Polymers

Advanced Materials Technologies, Journal Year: 2021, Volume and Issue: 6(4)

Published: Feb. 4, 2021

Abstract Important parameters of an organic semiconductor material are the electronic band gap ( E g ) and position highest occupied lowest unoccupied bands versus vacuum. These called valence conduction for inorganic semiconductors. For semiconductors defining often molecular orbital (HOMO) (LUMO). One advantage semiconducting polymers is ability to tune HOMO LUMO levels by chemical design. The photovoltaic solar cells need absorbers with a smaller bandgap maximize power conversion efficiency these devices. There several strategies synthesize low optoelectronic applications. In this manuscript, updated overview on current status conjugated will be given. design principles polymers, properties resulting materials, important applications devices realized class briefly discussed.

Language: Английский

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Reducing Voltage Losses in the A-DA′D-A Acceptor-Based Organic Solar Cells

Chem, Journal Year: 2020, Volume and Issue: 6(9), P. 2147 - 2161

Published: Sept. 1, 2020

Language: Английский

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A Quinoxaline‐Based D–A Copolymer Donor Achieving 17.62% Efficiency of Organic Solar Cells

Advanced Materials, Journal Year: 2021, Volume and Issue: 33(23)

Published: April 29, 2021

Abstract Side‐chain engineering has been an effective strategy in tuning electronic energy levels, intermolecular interaction, and aggregation morphology of organic photovoltaic materials, which is very important for improving the power conversion efficiency (PCE) solar cells (OSCs). In this work, two D–A copolymers, PBQ5 PBQ6, are designed synthesized based on bithienyl‐benzodithiophene (BDTT) as donor (D) unit, difluoroquinoxaline (DFQ) with different side chains acceptor (A) thiophene π‐bridges. PBQ6 alkyl‐substituted fluorothiophene DFQ units possesses redshifted absorption, stronger higher hole mobility than alkyl units. The blend film Y6 shows balanced hole/electron mobilities, less charge carrier recombination, more favorable morphology. Therefore, OSC PBQ6:Y6 achieves a PCE high 17.62% fill factor 77.91%, significantly (15.55%) PBQ5:Y6‐based OSC. by far one highest efficiencies binary OSCs polymer acceptor.

Language: Английский

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Regio‐Regular Polymer Acceptors Enabled by Determined Fluorination on End Groups for All‐Polymer Solar Cells with 15.2 % Efficiency

Angewandte Chemie International Edition, Journal Year: 2021, Volume and Issue: 60(18), P. 10137 - 10146

Published: Jan. 27, 2021

Abstract Polymerization sites of small molecule acceptors (SMAs) play vital roles in determining device performance all‐polymer solar cells (all‐PSCs). Different from our recent work about fluoro‐ and bromo‐ co‐modified end group IC‐FBr (a mixture IC‐FBr1 IC‐FBr2), this paper, we synthesized purified two regiospecific substituted groups (IC‐FBr‐ o & IC‐FBr‐ m ), which were then employed to construct regio‐regular polymer named PYF‐T‐ , respectively . In comparison with its isomeric counterparts different conjugated coupling sites, exhibits stronger bathochromic absorption achieve better photon harvesting. Meanwhile, adopts more ordered inter‐chain packing suitable phase separation after blending the donor PM6, resulted suppressed charge recombination efficient transport. Strikingly, observed a dramatic difference between While devices based on PM6:PYF‐T‐ can yield power conversion efficiency (PCE) 15.2 %, only show poor efficiencies 1.4 %. This demonstrates success configuration‐unique fluorinated designing high‐performance regular acceptors, provides guidelines towards developing all‐PSCs efficiencies.

Language: Английский

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A New Conjugated Polymer that Enables the Integration of Photovoltaic and Light‐Emitting Functions in One Device

Advanced Materials, Journal Year: 2021, Volume and Issue: 33(22)

Published: April 25, 2021

Abstract Exploring the intriguing bifunctional nature of organic semiconductors and investigating feasibility fabricating devices are great significance in realizing various applications with one device. Here, design a new wide‐bandgap polymer named PBQx‐TCl (optical bandgap 2.05 eV) is reported, its photovoltaic light‐emitting studied. By nonfullerene acceptors BTA3 BTP‐eC9, it shown that exhibit high power conversion efficiency (PCE) 18.0% under air mass 1.5G illumination conditions an outstanding PCE 28.5% for 1 cm 2 device 26.0% 10 from 1000 lux diode. In addition, PBQx‐TCl:BTA3‐based also demonstrates moderate diode performance electroluminescence external quantum approaching 0.2% broad emission range 630–1000 nm. These results suggest PBQx‐TCl‐based potential functions.

Language: Английский

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Benzothiadiazole-based non-fullerene acceptors

Nano Energy, Journal Year: 2021, Volume and Issue: 87, P. 106174 - 106174

Published: May 21, 2021

Language: Английский

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Optimized Active Layer Morphologies via Ternary Copolymerization of Polymer Donors for 17.6 % Efficiency Organic Solar Cells with Enhanced Fill Factor

Angewandte Chemie International Edition, Journal Year: 2020, Volume and Issue: 60(5), P. 2322 - 2329

Published: Oct. 15, 2020

Abstract Regulating molecular structure to optimize the active layer morphology is of considerable significance for improving power conversion efficiencies (PCEs) in organic solar cells (OSCs). Herein, we demonstrated a simple ternary copolymerization approach develop terpolymer donor PM6‐Tz20 by incorporating 5,5′‐dithienyl‐2,2′‐bithiazole (DTBTz, 20 mol%) unit into backbone PM6 (PM6‐Tz00). This method can effectively tailor orientation and aggregation polymer, then corresponding physical processes devices, ultimately boosting FF PCE. Hence, PM6‐Tz20: Y6‐based OSCs achieved PCE up 17.1% with significantly enhanced 0.77. Using Ag (220 nm) instead Al (100 as cathode, champion was further improved 17.6%. work provides effective design strategy photovoltaic performance.

Language: Английский

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Efficient, Thermally Stable, and Mechanically Robust All‐Polymer Solar Cells Consisting of the Same Benzodithiophene Unit‐Based Polymer Acceptor and Donor with High Molecular Compatibility

Advanced Energy Materials, Journal Year: 2020, Volume and Issue: 11(5)

Published: Dec. 21, 2020

Abstract All‐polymer solar cells (all‐PSCs) are a highly attractive class of photovoltaics for wearable and portable electronics due to their excellent morphological mechanical stabilities. Recently, new types polymer acceptors ( P A s) consisting non‐fullerene small molecule (NFSMAs) with strong light absorption have been proposed enhance the power conversion efficiency (PCE) all‐PSCs. However, polymerization NFSMAs often reduces entropy mixing in PSC blends prevents formation intermixed blend domains required efficient charge generation stability. One approach increase compatibility these systems is design s that contain same building blocks as donor D ) counterparts. Here, series NFSMA‐based [P(BDT2BOY5‐X), (X = H, F, Cl)] reported, by copolymerizing NFSMA (Y5‐2BO) benzodithiophene (BDT), common donating unit high‐performance such PBDB‐T. All‐PSC composed PBDB‐T P(BDT2BOY5‐X) show enhanced molecular compatibility, resulting electronic properties. Specifically, PBDB‐T:P(BDT2BOY5‐Cl) all‐PSC has PCE 11.12%, which significantly higher than previous PBDB‐T:Y5‐2BO (7.02%) PBDB‐T:P(NDI2OD‐T2) (6.00%) PSCs. Additionally, increased all‐PSCs greatly improves thermal stability robustness. For example, crack onset strain (COS) toughness 15.9% 3.24 MJ m –3 , respectively, comparison at 2.21% 0.32 .

Language: Английский

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