Publications by authors named "Tongle Xu"

The advancement of acceptors plays a pivotal role in determining photovoltaic performance. While previous efforts have focused on optimizing acceptor-donor-acceptor-donor-acceptor (A-DA-D-A)-typed acceptors by adjusting side chains, end groups, and conjugated extension of the electron-deficient central A unit, the systematic exploration of the impact of peripheral aryl substitutions, particularly with different electron groups, on the A unit and its influence on device performance is still lacking. In this study, three novel acceptors - QxTh, QxPh, and QxPy - with distinct substitutions on the quinoxaline (Qx) are designed and synthesized.

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With the widespread application of highly integrated electronic devices, the urgent development of multifunctional polymer-based composite materials with high electromagnetic interference shielding effectiveness (EMI SE) and thermal conductivity capabilities is critically essential. Herein, a graphene/carbon felt/polyimide (GCF/PI) composite is prepared through constructing 3D van der Waals heterostructure by heating carbon felt and graphene at high temperature. The GCF-3/PI composite exhibits the highest through-plane thermal conductivity with 1.

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The central core in A-DA D-A-type small-molecule acceptor (SMAs) plays an important role in determining the efficiency of organic solar cells (OSCs), while the principles governing the efficient design of SMAs remain elusive. Herein, we developed a series of SMAs with pyrido[2,3-b]quinoxaline (PyQx) as new electron-deficient unit by combining with the cascade-chlorination strategy, namely Py1, Py2, Py3, Py4 and Py5. The introduction of chlorine atoms reduces the intramolecular charge transfer effects but elevates the LUMO values.

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The technology of fault diagnosis helps improve the reliability of wind turbines. Difficulties in feature extraction and low confidence in diagnostic results are widespread in the process of deep learning-based fault diagnosis of wind turbine bearings. Therefore, a probabilistic Bayesian parallel deep learning (BayesianPDL) framework is proposed and then achieves fault classification.

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Although solvent additives are used to optimize device performance in many novel non-fullerene acceptor (NFA) organic solar cells (OSCs), the effect of processing additives on OSC structures and functionalities can be difficult to predict. Here, two polymer-NFA OSCs with highly sensitive device performance and morphology to the most prevalent solvent additive chloronaphthalene (CN) are presented. Devices with 1% CN additive are found to nearly double device efficiencies to 10%.

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Fluorination is one of the effective approaches to alter the organic semiconductor properties that impact the performance of the organic solar cells (OSCs). Positive effects of fluorination are also revealed in the application of fused ring electron acceptors (FREAs). However, in comparison with the efforts allocated to the material designs and power conversion efficiency enhancement, understanding on the excitons and charge carriers' behaviors in high-performing OSCs containing FREAs is limited.

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Achieving an ideal morphology is an imperative avenue for enhancing key parameters toward high-performing organic solar cells (OSCs). Among a myriad of morphological-control methods, the strategy of incorporating a third component with structural similarity and crystallinity difference to construct ternary OSCs has emerged as an effective approach to regulate morphology. A nematic liquid-crystalline benzodithiophene terthiophene rhodamine (BTR) molecule, which possesses the same alkylthio-thienyl-substituted benzo moiety but obviously stronger crystallinity compared to classical medium-bandgap polymeric donor PM6, is employed as a third component to construct ternary OSCs based on a PM6:BTR:Y6 system.

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Article Synopsis
  • Thick-film all-small-molecule organic solar cells (OSCs) are preferred for large-scale production due to their ease of use and consistency, but their efficiency is often limited by challenges in managing crystallinity and phase separation.
  • The study introduces BTR-OH, a modified version of a successful small molecule donor (BTR), which has lower crystallinity, and demonstrates that when paired with BTR and PCBM, the ternary device achieves a power conversion efficiency of 10.14%.
  • This efficiency improvement is attributed to better absorption, reduced recombination, enhanced charge extraction, and optimized material properties, showcasing BTR-OH as a beneficial component for improving thick-film OSCs.
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Nonfullerene acceptors (NFAs) based on calamitic-shaped small molecules are being developed rapidly to improve the photoelectron conversion efficiencies (PCEs) of organic solar cells. NFAs with light absorption extended to the near-infrared (NIR) region are of interest because they play a pivotal role in both organic tandem cells and semitransparent devices. In this work, two simple acceptor-donor-acceptor-structured NFAs (CPDT-4Cl and CPDT-4F) have been designed and synthesized.

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