Donor–acceptor mutually diluted heterojunctions for layer-by-layer fabrication of high-performance organic solar cells

Nature Energy, Год журнала: 2024, Номер 9(2), С. 208 - 218

Опубликована: Янв. 9, 2024

Язык: Английский

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Electrostatic force promoted intermolecular stacking of polymer donors toward 19.4% efficiency binary organic solar cells

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

Опубликована: Окт. 9, 2023

Conjugated polymers are generally featured with low structural order due to their aromatic and irregular units, which limits light absorption charge mobility in organic solar cells. In this work, we report a conjugated molecule INMB-F that can act as molecular bridge via electrostatic force enhance the intermolecular stacking of BDT-based polymer donors toward efficient stable Molecular dynamics simulations synchrotron X-ray measurements reveal electronegative adsorb on electropositive main chain increase donor-donor interactions, leading enhanced shortened π-π distance consequently transport ability. Casting non-fullerene acceptor layer top modified donor fabricate cells layer-by-layer deposition evidences significant power conversion efficiency boosts range photovoltaic systems. A 19.4% (certified 18.96%) is realized PM6/L8-BO binary devices, one highest reported efficiencies material system. The by also leads six-fold enhancement operational stability

Язык: Английский

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Double Asymmetric Core Optimizes Crystal Packing to Enable Selenophene‐based Acceptor with Over 18 % Efficiency in Binary Organic Solar Cells

Angewandte Chemie International Edition, Год журнала: 2023, Номер 62(10)

Опубликована: Янв. 2, 2023

Side-chain tailoring is a promising method to optimize the performance of organic solar cells (OSCs). However, asymmetric alkyl chain-based small molecular acceptors (SMAs) are still difficult afford. Herein, we adopted novel n-nonyl/undecyl substitution strategy and synthesized two A-D1 A'D2 -A double isomeric SMAs with selenophene-based central core for OSCs. Crystallographic analysis indicates that AYT9Se11-Cl forms more compact order intermolecular packing compared AYT11Se9-Cl, which contributed higher electron mobility in neat film. Moreover, PM6 : blend film shows better morphology appropriate phase separation distinct face-on orientation than AYT11Se9-Cl. The OSCs obtain superior PCE 18.12 % AYT11Se9-Cl (17.52 %), best efficiency selenium-incorporated binary BHJ Our findings elucidate chains precisely modulates crystal enhances photovoltaic selenophene-incorporated SMAs.

Язык: Английский

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Understanding the Role of Removable Solid Additives: Selective Interaction Contributes to Vertical Component Distributions

Advanced Materials, Год журнала: 2023, Номер 35(32)

Опубликована: Май 11, 2023

Abstract Sequentially deposited organic solar cells (SD‐OSCs) have attracted great attention owing to their ability in achieving a more favorable, vertically phase‐separated morphology avoid the accumulation of counter charges at absorber/transporting layer interfaces. However, processing SD‐OSCs is still quite challenging preventing penetration small‐molecule acceptors into polymer donor via erosion or swelling. Herein, solid additives (SAs) with varied electrostatic potential distributions and steric hinderance are introduced investigate effect evaporation dynamics selective interaction on vertical component distribution. Multiple modelings indicate that π – dominates interactions between aromatic SAs active components. Among them, p ‐dibromobenzene shows stronger while 2‐chloronaphthalene (2‐CN) interacts preferably acceptor. Combining depth‐dependent morphological study aided by multiple X‐ray scattering methods, it concluded can drive stronger‐interaction upward surface, having minor impact overall molecular packing. Ultimately, 2‐CN‐treated devices reduced acceptor concentration bottom surface deliver high power conversion efficiency 19.2%, demonstrating effectiveness applying improve OSCs using proper structure.

Язык: Английский

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Constructing Multiscale Fibrous Morphology to Achieve 20% Efficiency Organic Solar Cells by Mixing High and Low Molecular Weight D18

Advanced Materials, Год журнала: 2024, Номер 36(41)

Опубликована: Сен. 1, 2024

This study underscores the significance of precisely manipulating morphology active layer in organic solar cells (OSCs). By blending polymer donors D18 with varying molecular weights, a multiscale interpenetrating fiber network structure within is successfully created. The introduction 10% low weight (LW-D18) into high (HW-D18) produces MIX-D18, which exhibits an extended exciton diffusion distance and orderly stacking. Devices utilizing MIX-D18 demonstrate superior electron hole transport, improves dissociation, enhances charge collection efficiency, reduces trap-assisted recombination compared to other two materials. Through use nonfullerene acceptor L8-BO, remarkable power conversion efficiency (PCE) 20.0% achieved. methodology, integrates favorable attributes polymers, opens new avenue for enhancing performance OSCs.

Язык: Английский

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Impact of Intermolecular Interactions between Halogenated Volatile Solid Additives and the Nonfullerene Acceptor in Organic Solar Cells

Advanced Functional Materials, Год журнала: 2023, Номер 33(50)

Опубликована: Сен. 5, 2023

Abstract The halogenated volatile solid additives can delicately optimize the active layer morphology of organic solar cells, improving devices' performance, stability, and reproducibility. However, what type intermolecular interaction occurs between whether truly impacts donor or acceptor remains debatable. Herein, focus is on with conjugated benzene rings their influence composed PM6:Y6 as they evaporated. absorbance spectra exhibit apparent red‐shift features in Y6 absorption regions, while part unaffected. theoretical calculation results reveal that stay two molecules form halogen bonds, affecting π–π aggregation properties Y6. As a result, crystalline are altered, leading to increased charge carrier mobilities, extended diffusion lengths, reduced bimolecular recombination, thus device performance. Especially when 1,3,5‐tri bromobenzene used, champion power conversion efficiency 17.9% attained, among best‐performed cells comprising PM6:Y6. findings shed light experimental guidelines for designing developing highly efficient nonfullerene cells.

Язык: Английский

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Small Energetic Disorder Enables Ultralow Energy Losses in Non‐Fullerene Organic Solar Cells

Advanced Energy Materials, Год журнала: 2023, Номер 13(19)

Опубликована: Апрель 7, 2023

Abstract The relatively large non‐radiative recombination energy loss (Δ E 3 ) is the main source of losses in organic solar cells (OSCs). energetic disorder plays a crucial role losses; however, reducing by modifying terminal groups has rarely been investigated. Herein, four acceptors, BTP‐ICB1F, BTP‐ICB2F, BTP‐ICB3F, and BTP‐ICBCF3, with fluorinated phenyl are reported at identified substitution sites. theoretical experimental results show that this system possesses smaller than generally‐used Y6 acceptor due to strong electron polarization effect arising from tight, 3D molecular packing. Therefore, PM6:BTP‐ICBCF3 combination achieves high efficiency 17.8% open circuit voltage ( V OC 0.93 ultralow Δ 0.18 eV, which smallest for binary OSCs power conversion (PCEs) over 17% date. Lastly, using ternary strategy incorporating BTP‐ICBCF3 into PM6:BTP‐eC9, higher PCE 18.2% achieved enhanced . imply introducing new acceptors promising losses.

Язык: Английский

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Mitigating Exciton Recombination Losses in Organic Solar Cells by Engineering Nonfullerene Molecular Crystallization Behavior

Advanced Energy Materials, Год журнала: 2023, Номер 13(38)

Опубликована: Авг. 27, 2023

Abstract Although the advances in organic solar cells (OSCs) have been considerable, their efficiency is still limited by recombination losses. Photogenerated electrons and holes are generally bound as localized excitons semiconductors. The transition from into free charges requires diffusion dissociation processes, which parasitic losses exist. Reducing these necessary for highly efficient OSCs. crystallization behavior of active layers can influence exciton dissociation. In this work, different additives delicately designed to control behavior. It found that quality be improved controlling aggregation nonfullerene acceptors. π–π stacking blend films becomes compact, meanwhile, vertical direction more uniform. These beneficial excitons. As a consequence, reduced power convention efficiencies (PCEs) significantly. Meanwhile, general applicability additive demonstrated various photovoltaic systems, PCE 19.3% achieved D18:BTP‐eC9‐4F This work provides facile strategy reduce devices.

Язык: Английский

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Introducing a Phenyl End Group in the Inner Side Chains of A‐DA'D‐A Acceptors Enables High‐Efficiency Organic Solar Cells Processed with Nonhalogenated Solvent

Advanced Materials, Год журнала: 2023, Номер 35(48)

Опубликована: Июль 29, 2023

Power conversion efficiency (PCE) of organic solar cells (OSCs) processed by nonhalogenated solvents is unsatisfactory due to the unfavorable morphology. Herein, two new small molecule acceptors (SMAs) Y6-Ph and L8-Ph are synthesized introducing a phenyl end group in inner side chains SMAs Y6 L8-BO, respectively, for overcoming excessive aggregation long-time film forming solvents. First, effect time on property photovoltaic performance Y6, Y6-Ph, studied using commonly used solvents: chloroform (CF) (rapid process) chlorobenzene (CB) (slow process). It found that Y6- L8-BO-based OSCs exhibit dramatic drop PCE from CF- CB-processed devices owing large phase separation, while based show obviously increased PCEs Furthermore, L8-Ph-based solvent o-xylene (o-XY) achieved high 18.40% with an FF 80.11%. The results indicate effective strategy modulate morphology improve

Язык: Английский

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Cyano-functionalized pyrazine: an electron-deficient unit as a solid additive enables binary organic solar cells with 19.67% efficiency

Energy & Environmental Science, Год журнала: 2024, Номер 17(10), С. 3365 - 3374

Опубликована: Янв. 1, 2024

A strong electron-deficient unit CNPz as a solid additive was developed in PTQ10/ m -BTP-PhC6 binary organic solar cells. high PCE of 19.67% achieved with significant increase the J SC and FF (81.8%).

Язык: Английский

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