CHEMICAL ENGINEERING JOURNAL
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2023
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IF 15.1
Jingwen Yang,Chaochao Cao,Jiaxiao Qiao,Wei Qiao,Bo Jiang,Chengchun Tang,Yanming Xue
Lithium-sulfur (Li-S) battery with high theoretical specific capacity (1675 mAh/g), has been deemed as one of the most potential candidates of secondary energy storage system. However, the large-scale applications of Li-S batteries have been obstructed by internally sluggish multi-step redox reaction and terrible shuttle effect of lithium polysulfides (LiPSs). Herein, boron nitride nanosheets/reduced graphene oxide (BNNSs/rGO) heterostructure prepared by self-assembly crosslinking method has been designed to modify commercial separator for Li-S batteries. The hierarchical pores, physical and chemical cross-links within heterostructure can significantly enhance the adsorption capacity for LiPSs, uniquely physical and electronic interaction between BNNSs and rGO can effectively catalyze the conversion of sulfurated species. Benefiting from the synergistic adsorption-catalysis effect, BNNSs/rGO not only greatly inhibits the shuttle behaviors, but also considerably accelerates the electrochemical reaction kinetics for LiPSs and Li 2 S. Attributed to these merits, Li-S battery with BNNSs/rGO heterostructure mediator delivers superiorly reversible capacity as high as 915.0 mAh/g at 1 C. Even at high sulfur loading of 3.9 mg cm −2 , the cell delivers ultra-stable specific capacity of 629.1 mAh/g at 1 C, and still maintains 605.5 mAh/g over 500 cycles corresponding to a capacity fade of merely 0.0075% per cycle.
研究领域:
材料科学
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电化学
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储能系统
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DOI
高影响因子
COMPOSITES SCIENCE AND TECHNOLOGY
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2024
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IF 8.3
Qian Chen,Xiang Wang,Jianyu Liang,Tingting Zhang,Xingwu Jiang,Peifeng Liu
With the emergence of flexible electronics technologies based on stretchable, foldable, and bendable properties, there is a growing need for new thermal interface materials (TIMs) that possess better flexibility and stretchability. Epoxy resins, as thermal management materials commonly used to improve heat transfer and heat transport , need to have high thermal conductivity as well as excellent flexibility and a degree of stretchability. In order to devise TIMs that can be employed with flexible electronic devices, here we propose a strategy to form a flexible thermal conductive network structure with the shape of a “rice plant” inside the flexible epoxy resin matrix . The polyvinyl alcohol (PVA) flexible network skeleton constructed by the electrostatic spinning technique is regarded as the branches of the rice plant, and the ultra-sonicated boron nitride nanosheets (BNNS) are assumed to be the granular rice seeds. As a result, a perfect interconnected thermal conductivity path can be constructed, and the thermal conductivity is greatly enhanced with a relatively low boron nitride loading. Additionally, the prepared EP/PVA@S-BNNSs epoxy composites can exhibit a low elastic modulus and 153 % elongation at the break, demonstrating superior electrical insulation and excellent ductility, making them suitable for a wide range of applications in flexible electronic and wearable devices .
研究领域:
材料科学
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热管理技术
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产品关联
DOI
高影响因子
COMPOSITES COMMUNICATIONS
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2024
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IF 6.5
Rongcao Yu,Zhihai Lin,Minglong Luo,Bing Lei,Fengyuan Shu,Xin Yuan
In the challenging marine environment, organic coatings often fail to provide long-lasting protection. This study presents a novel approach for synthesizing multifunctional nano-pigments by utilizing hydrophobic and chemically bonded BNNSs@PDA/ODA nanosheets. The synthesis involves anchoring polydopamine (PDA) onto boron nitride nanosheets (BNNSs), followed by grafting octadecyl amine (ODA). This dual modification effectively prevents agglomeration of BNNSs and enhances their adhesion with silicone-epoxy resins at the interface. Comprehensive characterization confirms the successful grafting of ODA onto PDA-modified BN nanosheets, significantly improving the barrier properties of coatings. Remarkably, after immersing in a 3.5 wt% NaCl solution for 75 days, the composite coating BNNSs@PDA/ODA-SE exhibits an impedance modulus (|Z| 0.01Hz ) of 10 10 Ω cm 2 at low frequency, surpassing that of pure SE coating by nearly three orders of magnitude. The superior protective performance of the composite coating can be attributed to the synergistic effect between the physical barrier generated by BNNSs, insoluble complexes formed by Al 3+ -PDA, and the high hydrophobic surface network provided by ODA.
研究领域:
材料科学
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表面工程
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腐蚀防护
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产品关联
DOI
高影响因子
COMPOSITES SCIENCE AND TECHNOLOGY
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2020
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IF 7.094
Jianping Chen,Jingling Liu,Lixin Cai,Chunyan Wang,Liangliang Liu,Quanling Yang,Chuanxi Xiong
Due to the growing energy demands, it is highly desirable to concurrently improve the thermal conductivity and dielectric breakdown strength of dielectric film capacitors. Polyvinylidene fluoride (PVDF) is hitherto regarded as a most satisfactory alternative for dielectric capacitors but with relatively low thermal conductivity and dielectric breakdown strength. Herein, a major contribution is made to the concurrent enhancement of PVDF-based thermal conductivity and dielectric properties . It can be readily achieved through the incorporation of as-prepared high-quality few-layered boron nitride nanosheets (BNNSs) with a minimized loading (defined as PVDF-BNNSs). BNNSs dispersion with intact structure and a large aspect ratio is prepared by a unique mild mechanical stirring process assisted by dimethyformamide/1-butanol (DMF/1-butanol) solvent and a low power ultrasonic. Encouragingly, the characteristic breakdown strength with a maximum value of 334 MV/m reaches for PVDF-BNNSs composite only with 3 vol% BNNS loading, to be 1.6 times of pure PVDF. It also presents a high discharged energy density up to 9.9 J cm -3 , along with an efficiency of 68.3%. Synchronously, the thermal conductivity accomplishes a high value of 1.12 W/m·K with only 8 vol% BNNS loading. A further theoretical analysis reveals that high-quality appropriate BNNSs loading could be preferentially arranged in parallel with PVDF surface. It indicates that BNNSs have good interface compatibility with PVDF, thus to improve its associated performances concurrently.
研究领域:
材料科学
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电气工程
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产品关联
DOI
高影响因子
FOOD CHEMISTRY
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2021
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IF 7.514
Meng-Jun Li,Na Li,Guiju Xu,Ling-Xi Zhao,Xiangfeng Chen,Yanfang Zhao,Ru-Song Zhao
A novel magnetic boron nitride nanosheets (Fe 3 O 4 @BNNSs) composite-based magnetic solid-phase extraction (MSPE) method was employed to analyse six plant growth regulators (PGRs) in tomatoes combined with high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). The novel Fe 3 O 4 @BNNSs composite was prepared via an in situ chemical coprecipitation process and characterized by scanning electron microscopy (SEM), Fourier transform infrared spectrometry (FT-IR), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), and vibrating sample magnetometry (VSM). Several factors that may affect the extraction efficiencies were optimized. Under the optimal factors, low limits of detection (0.002–0.010 ng g −1 ), good linear ranges (0.05–10 ng g −1 ) and satisfactory precisions (intra-day: 1.2%-3.9%; inter-day: 2.1%-6.9%) were achieved. The established approach was successfully employed to extract and determine PGRs in tomatoes, and the spiked recoveries were between 85.2 and 109.0%.
研究领域:
分析化学
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纳米技术
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食品科学
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农业化学
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产品关联
DOI
PubMed
高影响因子
DIAMOND AND RELATED MATERIALS
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2025
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IF 5.1
Qi Hu,Chenhao Xu,Yulong Hua,Cunkang Qi,Jing Zhang,Yuemin Wang,Chengchun Tang
To explore the improvement of microwave absorption performance of boron nitride nanosheets (BNNSs) after doping with graphene quantum dots (GQDs). Herein, a series of point-layer structure BNNSs supported by GQDs composite absorbing materials were designed and prepared. The influence of the substrate on the wave absorption intensity was investigated by loading the same GQDs with BNNSs of different scales. Among them, the BG-1400 with BNNSs-1400 as the substrate and GQDs as the load has the best microwave absorption performance. Its minimum reflection loss ( RL min ) reaches −60.3 dB and the effective absorption frequency band is 8.5 GHz. In order to further analyze the factors influencing the effective absorption frequency bands of BNNSs/GQDs composites, BNG-1400 and BFG-1400 were prepared by loading N-GQDs and F-GQDs respectively on the BNNSs-1400 substrate, and their RL min and effective absorption frequency bands were -57.3 dB, −57.7 dB and 11.3 GHz, 13.4 GHz, respectively. The effective absorption frequency bands of BNG-1400 and BFG-1400 have been significantly improved compared with BG-1400.This indicates that the substrate size of the BNNSs/GQDs composite material can control its absorption intensity, while different doped elements in GQDs can adjust its effective absorption frequency band. This discovery lays the foundation for the research on the controllable adjustment of the wave absorption performance of BNNSs/GQDs composite absorbing materials.
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产品关联
DOI
高影响因子
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