Preparation of Dual-Asymmetric Acceptors via Selenium Substitution Combined with Terminal Group Optimization Strategy for High Efficiency Organic Solar Cells

Journal of the American Chemical Society, Journal Year: 2025, Volume and Issue: unknown

Published: Feb. 25, 2025

Improving both the open-circuit voltage (VOC) and short-circuit current density (JSC) through development of photovoltaic materials to achieve high power conversion efficiency (PCE) is critical a significant challenge for organic solar cells (OSCs). Here, we designed novel dual-asymmetric acceptors A-SSe-TCF A-SSe-LSF by simultaneously asymmetrically regulating backbone terminal groups investigated their synergistic effects on performance in comparison with monoasymmetric acceptor A-SSe-4F. The exhibit broader spectral absorption larger half-molecule dipole moment differences, which favored enhancement JSC reduction energy loss (Eloss). Among binary blends, PM6:A-SSe-TCF exhibits superior phase separation, vertical distribution morphology, more ordered π-π stacking compared PM6:A-SSe-LSF PM6:A-SSe-4F. As result, OSCs based achieved higher PCE 18.53% VOC due suppressed nonradiative recombination enhanced charge extraction capabilities. Furthermore, incorporating as third component, PM6:L8-BO:A-SSe-TCF-based device achieves champion 19.73% without account decrement Eloss. strategy provides new insights into molecular design improvement OSCs.

Language: Английский

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Fluorine/bromine/selenium multi-heteroatoms substituted dual-asymmetric electron acceptors for o-xylene processed organic solar cells with 19.12% efficiency

Science China Materials, Journal Year: 2024, Volume and Issue: unknown

Published: Nov. 15, 2024

Abstract The development of high-performance near-infrared (NIR) absorbing electron acceptors is a major challenge in achieving high short-circuit current density ( J SC ) to increase power conversion efficiency (PCE) organic solar cells (OSCs). Herein, three new multi-heteroatomized Y-series (bi-asy-Y-Br, bi-asy-Y-FBr, and bi-asy-Y-FBrF) were developed by combining dual-asymmetric selenium-fused core brominated end-groups with different numbers fluorine substitutions. With gradually increasing fluorination, exhibit red-shift absorption. Among them, bi-asy-Y-FBrF presents planar molecular geometry, the maximum average electrostatic potential, minimum dipole moment, which are conducive intramolecular packing charge transport. Moreover, D18:bi-asy-Y-FBrF active layer higher crystallinity, more suitable phase separation, reduced recombination compared D18:bi-asy-Y-Br D18:bi-asy-Y-FBr blends. Consequently, among theses binary OSCs, device achieves PCE 15.74% an enhanced 26.28 mA cm −2 , while obtains moderate 15.04% highest open-circuit voltage V OC 0.926 V. Inspired its complementary absorption NIR-absorbing BTP-eC9 as acceptor, bi-asy-Y-Br introduced into D18:BTP-eC9 construct ternary further boosted 19.12%, top values for reported green solvent processed OSCs.

Language: Английский

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Designing high-efficiency organic semi-conductors for organic photodetectors assisted by machine learning and property prediction

Chemical Physics, Journal Year: 2024, Volume and Issue: 582, P. 112295 - 112295

Published: April 11, 2024

Language: Английский

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Selenization Strategy of Phenazine‐based Non‐Fullerene Acceptors Promotes Photon Harvesting and Reduces Voltage Loss in Organic Solar Cells

Advanced Functional Materials, Journal Year: 2024, Volume and Issue: unknown

Published: Sept. 26, 2024

Abstract Phenazine‐based small molecular acceptors (SMAs), which benefit from the reduced energy loss ( E ), have emerged as promising candidates for achieving high‐efficiency organic solar cells (OSCs). Nevertheless, potential advancements of phenazine‐based photovoltaic devices are hindered by constrained short‐circuit current J sc ). Though incorporation selenium (Se) atoms has been proven effective in enhancing , it simultaneously introduces disorder stacking and charge recombination. Based on desire to harness full phenazine structure benefits Se substitution, a series Se‐substituted SMAs, namely PzIC‐SSe‐4F PzIC‐SeSe‐4F meticulously synthesized. Due increased photon harvesting capabilities, device using demonstrated significantly 27.73 mA cm −2 . Remarkably, PzIC‐SeSe‐4F‐based displayed an astonishing open circuit voltage V oc ) 0.873 V, representing highest recorded among all reported symmetric Y‐series SMAs‐based devices. Thanks synergistic effect central cores PM6:PzIC‐SeSe‐4F‐based achieves power conversion efficiency (PCE) 17.69%. The findings serve pivotal reference further development

Language: Английский

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Optimizing Exciton Diffusion and Carrier Transport for Enhanced Efficiency in Q‐PHJ and BHJ Organic Solar Cells

Advanced Functional Materials, Journal Year: 2024, Volume and Issue: unknown

Published: Nov. 5, 2024

Abstract Exciton diffusion and carrier transport are two critical factors that determine the efficiency of organic photovoltaics (OPVs). However, relationship between these has not been extensively studied. Designing non‐fullerene acceptors (NFAs) with efficient coefficients high electronic transmittance is a key area focus. In this study, materials for bulk‐heterojunction (BHJ) quasiplanar‐heterojunction (Q‐PHJ) devices synthesized to validate desired differences in crystallinity. The single crystal BOBO4Cl‐ βδ demonstrated most compact packing structure, an improved planar configuration closer π···π distances, resulting higher electron mobility superior exciton coefficient. Consequently, ‐based achieved power conversion (PCE) 17.38% Q‐PHJ, compared lower PCE 14.75% BHJ devices. Furthermore, incorporating into D18/L8‐BO Q‐PHJ system increased from 17.98% 18.81%, one highest values recorded This improvement attributed strong crystallinity , which enhances arrangement improves Our work highlights importance molecular design tunable OPV architectures reveals them, contributes achievement high‐performance NFAs.

Language: Английский

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