Role of Exciton Lifetime, Energetic Offsets, and Disorder in Voltage Loss of Bulk Heterojunction Organic Solar Cells DOI
Rakesh Suthar,

T. Abhijith,

Hemraj Dahiya

et al.

ACS Applied Materials & Interfaces, Journal Year: 2023, Volume and Issue: 15(2), P. 3214 - 3223

Published: Jan. 5, 2023

Recently, the power conversion efficiency (PCE) of organic solar cells (OSCs) has significantly progressed with a rapid increase from 10 to 19% due state-of-the-art research on nonfullerene acceptor molecules and various device processing strategies. However, OSCs still exhibit significant open circuit voltage loss (ΔVOC ∼ 0.6 V) high energetic offsets molecular disorder. In this work, we present systematic investigation determine effects offset disorder different recombination losses in (VOC) using 13 photoactive layers, wherein PCE ΔVOC vary ranges 2.21-14.74% 0.561-1.443 V, respectively. The detailed analysis all these devices was carried out, were correlated This enabled us identify key features for minimizing like: (1) low energy between donor states is essential attain nonradiative (ΔVOC, nrad) as ∼200 meV (2) Urbach energy, which measure materials' packing, should be minimization radiative rad). addition, time-resolved photoluminescence spectroscopy employed further understand exciton dynamics pristine materials donor-acceptor blends. It observed that absorbers ultralong lifetime (∼1000 ps) produce higher efficiencies. current study emphasizes importance simultaneously testing photovoltaic performance active layer rational optimization opens new prospects designing novel fine-tuning longer effective strategy boost their modified Shockley-Queisser (SQ) limit by losses.

Language: Английский

Regioregular Narrow‐Bandgap n‐Type Polymers with High Electron Mobility Enabling Highly Efficient All‐Polymer Solar Cells DOI
Huiliang Sun, Bin Liu, Yunlong Ma

et al.

Advanced Materials, Journal Year: 2021, Volume and Issue: 33(37)

Published: Aug. 2, 2021

Abstract Narrow‐bandgap n‐type polymers with high electron mobility are urgently demanded for the development of all‐polymer solar cells (all‐PSCs). Here, two regioregular narrow‐bandgap polymer acceptors, L15 and MBTI, electron‐deficient segments synthesized by copolymerizing dibrominated fused‐ring acceptors (FREA) distannylated aromatic imide, respectively. Taking full advantage FREA both show narrow bandgap mobility. Benefiting from more extended absorption, better backbone ordering, higher than those its regiorandom analog, L15‐based all‐PSC yields a power conversion efficiency (PCE) 15.2% when blended donor PM6. More importantly, MBTI incorporating benzothiophene‐core segment shows relatively frontier molecular orbital levels L15, forming cascade‐like energy level alignment Based on this, ternary all‐PSCs designed where is introduced as guest into PM6:L15 host system. Thanks to further optimal blend morphology balanced charge transport, PCE improved up 16.2%, which among highest values all‐PSCs. The results demonstrate that combining an imide construct provides effective approach fabricate highly efficient

Language: Английский

Citations

175
Achieving Record-Efficiency Organic Solar Cells upon Tuning the Conformation of Solid Additives DOI Creative Commons
Congqi Li, Xiaobin Gu,

Zhihao Chen

et al.

Journal of the American Chemical Society, Journal Year: 2022, Volume and Issue: 144(32), P. 14731 - 14739

Published: July 20, 2022

Volatile solid additives (SADs) are considered as a simple yet effective approach to tune the film morphology for high-performance organic solar cells (OSCs). However, structural effects of SADs on photovoltaic performance still elusive. Herein, two volatilizable were designed and synthesized. One is SAD1 with twisted conformation, while other one planar SAD2 S···O noncovalent intramolecular interactions (NIIs). The theoretical experimental results revealed that smaller space occupation can more easily insert between Y6 molecules, which beneficial form tighter intermolecular packing mode after thermal treatment. As result, SAD2-treated OSCs exhibited less recombination loss, balanced charge mobility, higher hole transfer rate, favorable morphology, resulting in record power conversion efficiency (PCE) 18.85% (certified PCE: 18.7%) single-junction binary OSCs. universality this study shed light understanding conformation performances

Language: Английский

Citations

168
High‐Efficiency Organic Solar Cells Based on a Low‐Cost Fully Non‐Fused Electron Acceptor DOI
Yuanyuan Zhou, Miao Li, Hao Lu

et al.

Advanced Functional Materials, Journal Year: 2021, Volume and Issue: 31(27)

Published: April 22, 2021

Abstract A series of tetrathiophene‐based fully non‐fused ring acceptors (4T‐1, 4T‐2, 4T‐3, and 4T‐4), which can be paired with the star donor polymer PBDB‐T to fabricate highly efficient organic solar cells are developed. Tailoring size lateral chains tune solubility packing mode acceptor molecules in neat blend films. It is found that incorporation 2‐ethylhexyl effectively change compatibility PBDB‐T, an encouraging power conversion efficiency 10.15% accomplished by 4T‐3‐based cells. also presents good other even higher (PCE) 12.04% achieved based on D18:4T‐3 blend, champion PCE for acceptors. Importantly, these inexpensive tetrathiophene provide cost‐effective photovoltaic performance. The results demonstrate a high performance from synthetically materials could rational design molecules.

Language: Английский

Citations

139
Semitransparent organic solar cells exhibiting 13.02% efficiency and 20.2% average visible transmittance DOI
Zhenghao Hu, Jian Wang, Xiaoling Ma

et al.

Journal of Materials Chemistry A, Journal Year: 2021, Volume and Issue: 9(11), P. 6797 - 6804

Published: Jan. 1, 2021

The PCEs of OSCs and AVTs corresponding blend films can be continuously optimized by adjusting D18-Cl:Y6-1O ratios introducing Y6 as the third component. 13.02% PCE 20.2% AVT are achieved in semitransparent ternary OSCs.

Language: Английский

Citations

125
Recent progress in all-small-molecule organic photovoltaics DOI

Chunyu Xu,

Zijin Zhao, Kaixuan Yang

et al.

Journal of Materials Chemistry A, Journal Year: 2022, Volume and Issue: 10(12), P. 6291 - 6329

Published: Jan. 1, 2022

This review systematically summarizes the development of all-small-molecule organic photovoltaics (SMPVs) from molecule engineering and device aspects, highlights challenges perspectives further developing SMPVs.

Language: Английский

Citations

78
Simultaneously Enhancing Exciton/Charge Transport in Organic Solar Cells by an Organoboron Additive DOI Creative Commons
Heng Lu, Kai Chen, Raja Sekhar Bobba

et al.

Advanced Materials, Journal Year: 2022, Volume and Issue: 34(42)

Published: Aug. 26, 2022

Efficient exciton diffusion and charge transport play a vital role in advancing the power conversion efficiency (PCE) of organic solar cells (OSCs). Here, facile strategy is presented to simultaneously enhance exciton/charge widely studied PM6:Y6-based OSCs by employing highly emissive trans-bis(dimesitylboron)stilbene (BBS) as solid additive. BBS transforms sites from more H-type aggregate into J-type aggregate, which benefits resonance energy transfer for PM6 Y6. Transient gated photoluminescence spectroscopy measurements indicate that addition improves coefficient dissociation excitons PM6:Y6:BBS film. absorption confirm faster generation PM6:Y6:BBS. Moreover, helps improve Y6 crystallization, current-sensing atomic force microscopy characterization reveals an improved charge-carrier length Owing enhanced diffusion, dissociation, generation, transport, well reduced recombination loss, higher PCE 17.6% with open-circuit voltage, short-circuit current density, fill factor achieved devices compared without (16.2%).

Language: Английский

Citations

77
Rapid dissociation of high concentration excitons between [Bi2O2]2+ slabs with multifunctional N-Bi-O sites for selective photoconversion into CO DOI
Guosheng Zhou,

Yangrui Xu,

Liang Chen

et al.

Applied Catalysis B Environment and Energy, Journal Year: 2023, Volume and Issue: 335, P. 122892 - 122892

Published: May 18, 2023

Language: Английский

Citations

72
Improving the Performance of Layer‐by‐Layer Processed Organic Solar Cells via Introducing a Wide‐Bandgap Dopant into the Upper Acceptor Layer DOI

Qiaoling Chen,

Hao Huang,

Di Hu

et al.

Advanced Materials, Journal Year: 2023, Volume and Issue: 35(28)

Published: May 2, 2023

Abstract The layer‐by‐layer (LbL) solution‐processed organic solar cells (OSCs) are conductive to achieve vertical phase separation, tunable donor–acceptor (D/A) interfaces, and favorable charge‐transport pathways. In this work, a wide‐bandgap component poly(9‐vinylcarbazole) (PVK) is added the upper electron acceptor layer improve performance of LbL‐processed OSCs. Results show that PVK can adjust film morphology, dope acceptor, increase concentration, charge transport. Such n‐type doping verified by Seebeck coefficient measurement, ultraviolet photoelectron spectroscopy, paramagnetic resonance characterization. addition, fluorescence intensity exciton lifetime PVK‐doped increased, thus being beneficial for diffusion D/A interface. Therefore, power conversion efficiency (PCE) LbL OSCs increases when 2.50 wt.% employed in commonly‐used high‐efficiency system maximum value 19.05% be achieved. role played active different from those additives ternary components reported previously, so results provide an alternative way enhance device

Language: Английский

Citations

66
π–π Stacking Modulation via Polymer Adsorption for Elongated Exciton Diffusion in High‐Efficiency Thick‐Film Organic Solar Cells DOI

Zhen Fu,

Jiawei Qiao,

Fengzhe Cui

et al.

Advanced Materials, Journal Year: 2024, Volume and Issue: 36(21)

Published: Feb. 22, 2024

Abstract Developing efficient organic solar cells (OSCs) with thick active layers is crucial for roll‐to‐roll printing. However, thicker often result in lower efficiency. This study tackles this challenge using a polymer adsorption strategy combined layer‐by‐layer approach. Incorporating insulator polystyrene (PS) into the PM6:L8‐BO system creates PM6+PS:L8‐BO blends, effectively suppressing trap states and extending exciton diffusion length mixed donor domain. Adding insulating polymers benzene rings to enhances π–π stacking of donors, boosting intermolecular interactions electron wave function overlap. results more orderly molecular stacking, longer lifetimes, higher lengths. The promoted long‐range leads high power conversion efficiencies 19.05% 18.15% blend films 100 300 nm thickness, respectively, as well respectable 16.00% 500 nm. These insights guide material selection better diffusion, offer method thick‐film OSC fabrication, promoting prosperous future practical mass production.

Language: Английский

Citations

43
Suppressing Exciton‐Vibration Coupling to Prolong Exciton Lifetime of Nonfullerene Acceptors Enables High‐Efficiency Organic Solar Cells DOI
Yufan Zhu, Dan He, Chong Wang

et al.

Angewandte Chemie International Edition, Journal Year: 2024, Volume and Issue: 63(8)

Published: Jan. 5, 2024

Abstract The limited exciton lifetime ( τ , generally <1 ns) leads to short diffusion length L D ) of organic semiconductors, which is the bottleneck issue impeding further improvement power conversion efficiencies (PCEs) for solar cells (OSCs). However, efficient strategies prolong intrinsic are rare and vague. Herein, we propose a facile method efficiently reduce vibrational frequency molecular skeleton suppress exciton‐vibration coupling decrease non‐radiative decay rate thus via deuterating nonfullerene acceptors. remarkably increases from 0.90 ns (non‐deuterated L8‐BO) 1.35 (deuterated L8‐BO‐D), record photovoltaic materials. Besides, inhibited vibration improves planarity L8‐BO‐D enhanced coefficient. Consequently, 7.9 nm (L8‐BO) 10.7 (L8‐BO‐D). prolonged enables PM6 : L8‐BO‐D‐based bulk heterojunction OSCs acquire higher PCEs 18.5 % with more dissociation weaker charge carrier recombination than L8‐BO‐based counterparts. Moreover, benefiting D18/L8‐BO‐D‐based pseudo‐planar achieve an impressive PCE 19.3 %, among highest values. This work provides strategy increase boosting OSCs.

Language: Английский

Citations

35