core-shell structure

  • 文章类型: Journal Article
    在能源短缺的大背景下,氢能作为绿色清洁能源备受关注。为了探索高效的制氢途径,我们设计了一种碳基核壳光热辅助光催化体系(Carbon@ZnIn2S4,记为C@ZIS)的复合光催化剂。精心设计的催化剂C@ZIS复合材料即使在不存在贵金属Pt助催化剂的情况下也表现出2.97mmolg-1h-1的光催化氢沉淀速率。将基于碳的核-壳光催化剂结合到光催化反应中通过在反应溶液中引发光热效应而显著影响反应的活性。物理化学实验结果表明,C@ZIS复合体系中的碳球可以提供更多的活性位点,从而加速电子转移和分离效率,从而提高了光催化活性。该研究提出了一种有效的设计概念,用于开发有效的碳基核壳光热辅助光催化剂,这有望促进太阳能到氢能的有效转化。
    Against the backdrop of energy shortage, hydrogen energy has attracted much attention as a green and clean energy source. In order to explore efficient hydrogen production pathways, we designed a composite photocatalyst with carbon-based core-shell photothermal-assisted photocatalytic system (Carbon@ZnIn2S4, denoted as C@ZIS). The well-designed catalyst C@ZIS composites demonstrated a photocatalytic hydrogen precipitation rate of 2.97 mmol g-1 h-1 even in the absence of the noble metal Pt co-catalyst. The incorporation of carbon-based core-shell photocatalysts into a photocatalytic reaction significantly affects the activity of the reaction by triggering a photothermal effect in the reaction solution. The results of the physicochemical experiments demonstrated that the carbon spheres in C@ZIS composite system could provide a greater number of active sites, thereby accelerating the electron transfer and separation efficiency, and thus enhancing the photocatalytic activity. The study presents an efficacious design concept for the development of efficacious carbon-based core-shell photothermal-assisted photocatalysts, which is anticipated to facilitate the efficient conversion of solar energy to hydrogen energy.
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  • 文章类型: Journal Article
    具有独特形貌的核壳异质结构的发展可以改善混合超级电容器(HSC)的电化学性能。这里,利用水热合成在镍泡沫(NF)上垂直生长CuCo2S4纳米线阵列(NWAs)。然后,通过电沉积将CoMo-LDH纳米片均匀地沉积在CuCo2S4NWAs上,以获得CoMo-LDH@CuCo2S4NWAs/NF电极。由于CuCo2S4(核)的优越导电性和CoMo-LDH(壳)的良好氧化还原活性,电极表现出优异的电化学性能。在1Ag-1时,电极的比容量为1271.4Cg-1,经过10,000次循环,在10Ag-1时,其容量保持率为92.2%。在983.9Wkg-1的功率密度下,CoMo-LDH@CuCo2S4NWAs/NF//AC/NF器件的能量密度为52.2Whkg-1。这表明CoMo-LDH@CuCo2S4/NF具有用于超级电容器的巨大潜力。
    The development of core-shelled heterostructures with the unique morphology can improve the electrochemical properties of hybrid supercapacitors (HSC). Here, CuCo2S4 nanowire arrays (NWAs) are vertically grown on nickel foam (NF) utilizing hydrothermal synthesis. Then, CoMo-LDH nanosheets are uniformly deposited on the CuCo2S4 NWAs by electrodeposition to obtain the CoMo-LDH@CuCo2S4 NWAs/NF electrode. Due to the superior conductivity of CuCo2S4 (core) and good redox activity of CoMo-LDH (shell), the electrode shows excellent electrochemical properties. The electrode\'s specific capacity is 1271.4 C g-1 at 1 A g-1, and after 10, 000 cycles, its capacity retention ratio is 92.2 % at 10 A g-1. At a power density of 983.9 W kg-1, the CoMo-LDH@CuCo2S4 NWAs/NF//AC/NF device has an energy density of 52.2 Wh kg-1. This indicates that CoMo-LDH@CuCo2S4/NF has a great potential for supercapacitors.
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  • 文章类型: Journal Article
    CuS由于其强大的功能和环保特性,在钠离子电池中作为负极材料的应用受到了广泛的关注。然而,由于在充放电过程中钠离子的非均相转移,实现高倍率性能和长循环稳定性是一个挑战,硫化铜的内部导电性差和重复的体积膨胀。在这项研究中,设计并构建了掺Sb碳壳包覆的CuS中空纳米立方体(Sb-CuS@C)作为钠离子电池的负极纳米材料。由于碳壳固有的良好电子传导性和化学稳定性,Sb-CuS@C作为阳极材料具有较高的整体电子转移,避免了循环过程中的团聚和结构破坏。因此,在0.5Ag-1下进行100次循环后,合成的Sb-CuS@C实现了595mAhg-1的出色可逆容量,在较高的10Ag-1下具有340mAhg-1的良好倍率性能。DFT计算表明,均匀掺杂的Sb将充当活性亲钠成核位点,以帮助在放电过程中吸附Na并导致均匀的钠沉积。这项工作为常见的过渡金属硫化物在SIB中用作阳极材料的结构和成分改性提供了新的见解。
    CuS have received widespread attention for application as anode materials in sodium-ion batteries due to their potent capabilities and eco-friendly properties. However, it is a challenge to achieve a high rate capability and long cycle stability owing to the heterogeneous transfer of sodium ions during charge-discharge, the interior poor electron conductivity and repeated volumetric expansion of copper sulfide. In this study, Sb-doped CuS hollow nanocubes coated with carbon shells (Sb-CuS@C) was designed and constructed as anode nanomaterials in sodium ion batteries. Thanks to the intrinsic good electron conductivity and chemical stability of carbon shells, Sb-CuS@C possesses a higher overall electron transfer as anode material, avoids agglomeration and structural destruction during the cycling. As a result, the synthesized Sb-CuS@C achieved an excellent reversible capacity of 595 mA h g-1 after 100 cycles at 0.5 A g-1 and a good rate capability of 340 mA h g-1 at a higher 10 A g-1. DFT calculations clarify that the uniformly doped Sb would act as active sodiophilic nucleation sites to help adsorbing Na+ during discharging and leading uniform sodium deposition. This work provides a new insight into the structural and componential modification for common transition-metal sulfides towards application as anode materials in SIB.
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  • 文章类型: Journal Article
    高效材料的选择和有利结构的构造对于实现高性能电极材料至关重要。在本文中,通过简单的水热和煅烧技术,成功地设计并制备了具有优异形貌和高性能的电极材料Cu2S/C@NiMnCe-LDH/CF。首先,将ZIF-67负载在Cu2S棒的外层上,得到核壳结构的Cu2S@ZIF-67棒,将其ZIF-67MOF壳碳化以获得Cu2S@C棒。然后,将NiMnCe-LDH外延负载在Cu2S@C外层上,获得Cu2S/C@NiMnCe-LDH棒。在2mAcm-2的电流密度下,Cu2S/C@NiMnCe-LDH/CF的面积电容为5176.4mFcm-2。Cu2S/C@NiMnCe-LDH/CF//AC非对称超级电容器(ASC)的质量电容和能量密度在0.8A/g的扫描速率下达到150.82Fg-1,在功率密度为639.99Wkg-1的情况下达到53.62Whkg-1。同时,8000次电化学循环后,Cu2S/C@NiMnCe-LDH/CF//AC的比电容仍有86.32%的保留率,证明了其优异的循环稳定性。这些结果表明了制备新型核-壳结构Cu2S/C@NiMnCe-LDH/CF纳米复合材料的新策略,该材料用于储能器件的电极材料,具有出色的性能。
    The selection of highly efficient materials and the construction of advantageous structures are essential for realizing high-performance electrode materials. In this paper, electrode material Cu2S/C@NiMnCe-LDH/CF with excellent morphology and high performance has been successfully designed and prepared by simple hydrothermal and calcination techniques. First, ZIF-67 is loaded on the outer layer of Cu2S rods to obtain core-shell structured Cu2S@ZIF-67 rods, whose ZIF-67 MOF shell is carbonized to obtain Cu2S@C rods. Then, NiMnCe-LDH are epitaxially loaded on the outer layer of Cu2S@C to obtain Cu2S/C@NiMnCe-LDH rods. At a current density of 2 mA cm-2, Cu2S/C@NiMnCe-LDH/CF exhibits an area capacitance of 5176.4 mF cm-2. The mass capacitance and the energy density of the Cu2S/C@NiMnCe-LDH/CF//AC asymmetric supercapacitor (ASC) reach 150.82F g-1 at a sweep rate of 0.8 A/g and 53.62 Wh kg-1 at a power density of 639.99 W kg-1, respectively. Meanwhile, after 8000 electrochemical cycles, the specific capacitance of Cu2S/C@NiMnCe-LDH/CF//AC still has a retention rate of 86.32 %, which proves its excellent cycling stability. These results demonstrate a new strategy for the preparation of novel core-shell structured Cu2S/C@NiMnCe-LDH/CF nanocomposite material for electrode materials of energy storage devices with superb performance.
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  • 文章类型: Journal Article
    一种通过与淀粉和原儿茶酸(PA)共糊化改性的新型核壳结构的基于海藻酸盐的水凝胶珠,旨在调节珠子的物理性质,包封的生物活性物质的释放行为和抗氧化稳定性。核心是通过离子凝胶化制造的,其配方(海藻酸钠/淀粉的比例)由颗粒大小/淀粉分布确定,质地和核心的生物活性封装能力。然后,用与不同剂量的PA共糊化的壳形成溶液涂覆核,并随后与Ca2+交联以获得核-壳结构的珠子。表面微观结构,机械特性,颗粒的溶胀率受到PA浓度的影响。此外,含有PA的核-壳结构可以在体外消化过程中增强包封的酚类生物活性物质的递送和持续释放,并提高其抗氧化潜力的稳定性。此外,通过FTIR和TGA阐明了PA与多糖成分之间的相互作用。目前的信息有利于功能食品材料和生物活性递送系统的发展。
    A novel core-shell structured alginate-based hydrogel bead modified by co-gelatinizing with starch and protocatechuic acid (PA), was designed to modulate physical properties of beads, release behavior and antioxidant stability of encapsulated bioactives. Core was fabricated by ionotropic gelation, and its formulation (ratio of sodium alginate/starch) was determined by particle size/starch distribution, texture and bioactive encapsulation capacity of core. Then, coating core with shell-forming solution co-gelatinized with different doses of PA, and subsequently cross-linked with Ca2+ to obtain core-shell structured beads. Surface microstructure, mechanical characteristics, and swelling ratio of beads were affected by concentrations of PA. Besides, core-shell structure containing PA could enhance delivery and sustained release of encapsulated phenolic bioactives during in vitro digestion, and improve their antioxidant potential stability. Furthermore, interaction between PA and polysaccharide components was elucidated by FTIR and TGA. The present information was beneficial for the advancement of functional food materials and bioactive delivery systems.
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  • 文章类型: Journal Article
    蓄热水泥基材料,通过将相变材料集成到胶凝材料中形成,作为储能材料表现出巨大的潜力。然而,导热性差严重限制了这些材料的发展和应用。在这项研究中,将无定形SiO2壳包封在石墨表面上以产生新型的热改性混合物(C@SiO2)。这种材料表现出优异的导热性,表面包裹的无定形SiO2增强了其与水泥的结合。Further,C@SiO2以不同的体积比添加到蓄热水泥基材料中。通过测量流动性来评价C@SiO2的效果,热导率,相变属性,温度变化,各种蓄热水泥基材料的抗压强度。结果表明,与普通蓄热水泥基材料相比,新设计的10vol%C@SiO2蓄热水泥基材料的导热系数提高了63.6%,相变潜热提高了11.2%。此外,C@SiO2对蓄热水泥基材料的流动性和抗压强度没有显著影响。这项研究表明,C@SiO2是一种有前途的添加剂,用于增强蓄热水泥基材料的导热性。新设计的具有10vol%C@SiO2的蓄热水泥基材料是储能应用的有希望的候选材料。
    Thermal storage cement-based materials, formed by integrating phase change materials into cementitious materials, exhibit significant potential as energy storage materials. However, poor thermal conductivity severely limits the development and application of these materials. In this study, an amorphous SiO2 shell is encapsulated on a graphite surface to create a novel thermally modified admixture (C@SiO2). This material exhibits excellent thermal conductivity, and the surface-encapsulated amorphous SiO2 enhances its bond with cement. Further, C@SiO2 was added to the thermal storage cement-based materials at different volume ratios. The effects of C@SiO2 were evaluated by measuring the fluidity, thermal conductivity, phase change properties, temperature change, and compressive strength of various thermal storage cement-based materials. The results indicate that the newly designed thermal storage cement-based material with 10 vol% C@SiO2 increases the thermal conductivity coefficient by 63.6% and the latent heat of phase transition by 11.2% compared to common thermal storage cement-based materials. Moreover, C@SiO2 does not significantly impact the fluidity and compressive strength of the thermal storage cement-based material. This study suggests that C@SiO2 is a promising additive for enhancing thermal conductivity in thermal storage cement-based materials. The newly designed thermal storage cement-based material with 10 vol% C@SiO2 is a promising candidate for energy storage applications.
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  • 文章类型: Journal Article
    稀土掺杂纳米粒子的核壳设计研究最近受到了广泛的关注,特别是在探索结合活性和惰性壳层的协同效应。在这项研究中,我们成功合成了8种球形核壳钠基纳米粒子,通过惰性层和活性层的战略性排列,提高了核壳设计在上转换发光和温度传感中的效率。使用NaYF4惰性壳NaYF4:Yb3+在980nm和808nm激光激发下观察到最有效的上转换发光,Er3+@NaYF4和NaYF4@NaYF4:Yb3+,Nd3+核壳纳米结构。此外,NaYbF4活性壳结构的掺入导致比率发光测温法的相对灵敏度显着提高。值得注意的是,NaYF4:Yb3+,Nd3+,Er3+@NaYbF4核壳结构表现出1.12%K-1的最高相对灵敏度。这项研究强调了惰性壳层在增强核壳结构设计中的上转换发光中的关键作用,而有源层在实现高灵敏度温度检测能力方面起着关键作用。
    Research on the core-shell design of rare earth-doped nanoparticles has recently gained significant attention, particularly in exploring the synergistic effects of combining active and inert shell layers. In this study, we successfully synthesized 8 types of spherical core-shell Na-based nanoparticles to enhance the efficiency of core-shell design in upconversion luminescence and temperature sensing through the strategic arrangement of inert and active layers. The most effective upconversion luminescence was observed under 980 nm and 808 nm laser excitation using NaYF4 inert shell NaYF4:Yb3+, Er3+@ NaYF4 and NaYF4@ NaYF4:Yb3+, Nd3+ core-shell nanostructures. Moreover, the incorporation of the NaYbF4 active shell structure led to a significant increase in relative sensitivity in ratio luminescence thermometry. Notably, the NaYF4:Yb3+, Nd3+, Er3+@ NaYbF4 core-shell structure demonstrated the highest relative sensitivity of 1.12 %K-1. This research underscores the crucial role of inert shell layers in enhancing upconversion luminescence in core-shell structure design, while active layers play a key role in achieving high-sensitivity temperature detection capabilities.
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  • 文章类型: Journal Article
    传统Ag基抗菌剂的使用通常伴随着无法控制的银释放,这使得很难在抗菌性能和生物安全性之间找到平衡。在这里,我们制备了ZIF-8衍生的无定形碳包覆Ag纳米颗粒(Ag@C)的核-壳体系作为理想的研究模型,以揭示碳壳和Ag核的结构转变对银释放行为的调节作用和构效关系。发现在600°C(AC6)下制备的Ag@C表现出最佳的离子释放动力学,这是由于相对简单的壳结构和Ag核的较低结晶度的结合,从而与大多数其他Ag基材料相比,在痕量剂量(20μgmL-1)下发挥更强的抗菌性能(>99.999%)。同时,碳壳可防止金属Ag直接暴露于生物体,从而赋予AC6优异的生物相容性。在动物实验中,AC6可通过灭活耐药菌有效促进创面愈合,同时调节TNF-α和CD31的表达。该工作为可控离子释放抗菌剂的科学设计和临床应用提供了理论支持。
    The use of traditional Ag-based antibacterial agents is usually accompanied by uncontrollable silver release, which makes it difficult to find a balance between antibacterial performance and biosafety. Herein, we prepared a core-shell system of ZIF-8-derived amorphous carbon-coated Ag nanoparticles (Ag@C) as an ideal research model to reveal the synergistic effect and structure-activity relationship of the structural transformation of carbon shell and Ag core on the regulation of silver release behavior. It is found that Ag@C prepared at 600 °C (AC6) exhibits the best ion release kinetics due to the combination of relatively simple shell structure and lower crystallinity of the Ag core, thereby exerting stronger antibacterial properties (>99.999 %) at trace doses (20 μg mL-1) compared with most other Ag-based materials. Meanwhile, the carbon shell prevents the metal Ag from being directly exposed to the organism and thus endows AC6 with excellent biocompatibility. In animal experiments, AC6 can effectively promote wound healing by inactivating drug-resistant bacteria while regulating the expression of TNF-α and CD31. This work provides theoretical support for the scientific design and clinical application of controllable ion-releasing antibacterial agents.
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  • 文章类型: Journal Article
    作为一种具有生物降解性的半透明功能凝胶,无毒和耐酸,结冷胶已广泛用于益生菌包装,药物输送,伤口敷料,近年来在金属离子吸附等领域。由于其显著的凝胶化特性,结冷胶适合作为微胶囊的外壳材料来封装功能性物质,通过这些功能组分可以提高稳定性并实现延迟释放。近年来,许多学术或商业上可靠的产品迅速出现,但是关于微胶囊形成过程及其相应机制的深入研究和系统总结,仍然缺乏相关报道。为了应对这一挑战,本文综述了结冷胶基微胶囊的形成过程和应用,并详细介绍了微胶囊生产中常用的制备方法。此外,它探讨了离子类型等因素的影响,离子强度,温度,pH值,和其他存在于溶液中的微胶囊的性能。在此基础上,总结分析了结冷胶微胶囊产品的发展前景。这篇综述的全面见解有望为研究人员提供灵感和设计思路。
    As a translucent functional gel with biodegradability, non-toxicity and acid resistance, gellan gum has been widely used in probiotic packaging, drug delivery, wound dressing, metal ion adsorption and other fields in recent years. Because of its remarkable gelation characteristics, gellan gum is suitable as the shell material of microcapsules to encapsulate functional substances, by which the functional components can improve stability and achieve delayed release. In recent years, many academically or commercially reliable products have rapidly emerged, but there is still a lack of relevant reports on in-depth research and systematic summaries regarding the process of microcapsule formation and its corresponding mechanisms. To address this challenge, this review focuses on the formation process and applications of gellan gum-based microcapsules, and details the commonly used preparation methods in microcapsule production. Additionally, it explores the impact of factors such as ion types, ion strength, temperature, pH, and others present in the solution on the performance of the microcapsules. On this basis, it summarizes and analyzes the prospects of gellan gum-based microcapsule products. The comprehensive insights from this review are expected to provide inspiration and design ideas for researchers.
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  • 文章类型: Journal Article
    在这项研究中,首先通过Na2SeO3/Vc氧化还原反应制备黑莓多糖-硒纳米颗粒(BBP-24-3Se),然后用红细胞膜(RBC)包被,形成核-壳结构的多糖-硒纳米颗粒(RBC@BBP-24-3Se)。BBP-24-3Se(167.1nm)的粒径增加到239.8nm(RBC@BBP-24-3Se),在用RBC包覆后具有明显的核壳结构。FT-IR和XPS结果表明,BBP-24-3与SeNPs之间的相互作用形成了一个新的C-O··Se键,价态为Se0。生物测定表明,RBC涂层显着增强了RBC@BBP-24-3Se的生物相容性和生物吸收性。浓度为10μg/mL时,RBC@BBP-24-3Se在HepG2细胞中的吸收率是BBP-24-3Se的4.99倍。与BBP-24-3Se相比,RBC@BBP-24-3Se对棕榈酸诱导的HepG2细胞氧化损伤具有明显的保护作用,对糖脂代谢紊乱具有更好的调节作用。机制研究表明,RBC@BBP-24-3Se可有效改善PI3K/AKT信号通路促进糖代谢,抑制脂质合成基因的表达,通过AMPK信号通路上调脂质分解基因的表达,从而改善脂质代谢。这些结果为开发新型补硒治疗胰岛素抵抗提供了理论依据。
    In this study, blackberry polysaccharide-selenium nanoparticles (BBP-24-3Se) were first prepared via Na2SeO3/Vc redox reaction, followed by coating with red blood cell membrane (RBC) to form core-shell structure polysaccharide-selenium nanoparticles (RBC@BBP-24-3Se). The particle size of BBP-24-3Se (167.1 nm) was increased to 239.8 nm (RBC@BBP-24-3Se) with an obvious core-shell structure after coating with RBC. FT-IR and XPS results indicated that the interaction between BBP-24-3 and SeNPs formed a new C-O···Se bond with valence state of Se0. Bioassays indicated that RBC coating markedly enhanced both the biocompatibility and bioabsorbability of RBC@BBP-24-3Se, and the absorption rate of RBC@BBP-24-3Se in HepG2 cells was 4.99 times higher than that of BBP-24-3Se at a concentration of 10 μg/mL. Compared with BBP-24-3Se, RBC@BBP-24-3Se possessed significantly heightened protective efficacy against oxidative damage and better regulation of glucose/lipid metabolism disorder induced by palmitic acid in HepG2 cells. Mechanistic studies demonstrated that RBC@BBP-24-3Se could effectively improve PI3K/AKT signaling pathway to promote glucose metabolism, inhibit the expression of lipid synthesis genes and up-regulate the expression of lipid-decomposing genes through AMPK signaling pathway to improve lipid metabolism. These results provided a theoretical basis for developing a new type of selenium supplement for the treatment of insulin resistance.
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