IF 10.5 2区材料科学 Q1 CHEMISTRY, PHYSICAL

Carbon

Pub Date : 2024-10-30 DOI: 10.1016/j.carbon.2024.119764

Cuijuan Xing , Aiqing Xia , Weitao Li , Shanyan Chang , Lili Dong , Jipeng Xu , Yifan Kang , Jiacheng Ma , Fan Wu , Lei Zhang , Wenhuan Huang

Developing electromagnetic wave-absorbing (EMWA) materials that offer robust absorption capabilities, broad operational bandwidth, and low weight remains a critical challenge. Achieving optimal absorption efficiency through the strategic integration of EMWA components is a promising approach. we report the fabrication and optimization of PEDOT/Fe₃O₄ anchored on a reduced graphene oxide (rGO) heterostructure as an effective EMWA material. Our results demonstrate that the electromagnetic synergy, enhanced by numerous hetero-interfaces, facilitates impedance matching and amplifies dielectric losses, magnetic losses, polarization, and multiple reflection phenomena. The EMWA performance of the PEDOT/Fe₃O₄/rGO heterostructure can be finely tuned by adjusting the rGO content, thereby optimizing microwave absorption properties. Due to its structural and compositional advantages, the minimum reflection loss (RL_min) reaches an impressive −52.4 dB at a thickness of 1.46 mm, covering an effective absorption bandwidth (EAB) exceeding 3.52 GHz. These findings establish critical benchmarks for the intentional design of multi-interface electromagnetic absorbers, offering high-efficiency wave absorption for practical applications in electromagnetic radiation management.

开发具有强大吸收能力、宽工作带宽和低重量的电磁波吸收（EMWA）材料仍然是一项严峻的挑战。我们报告了锚定在还原氧化石墨烯（rGO）异质结构上的 PEDOT/Fe3O4 作为有效 EMWA 材料的制造和优化。我们的研究结果表明，众多异质界面增强了电磁协同作用，促进了阻抗匹配，并放大了介电损耗、磁损耗、极化和多重反射现象。PEDOT/Fe3O4/rGO 异质结构的 EMWA 性能可通过调整 rGO 含量进行微调，从而优化微波吸收特性。由于其结构和成分优势，在厚度为 1.46 mm 时，最小反射损耗 (RLmin) 达到了令人印象深刻的 -52.4 dB，有效吸收带宽 (EAB) 超过 3.52 GHz。这些发现为有意设计多界面电磁吸收器确立了关键基准，为电磁辐射管理的实际应用提供了高效率的波吸收。

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引用次数: 0

Vacancy-induced interfacial crosslinking in graphene/carbon nanotube composites and its influence on mechanical behaviors: A molecular dynamics simulation 石墨烯/碳纳米管复合材料中空位诱导的界面交联及其对力学行为的影响：分子动力学模拟

IF 10.5 2区材料科学 Q1 CHEMISTRY, PHYSICAL

Carbon

Pub Date : 2024-10-29 DOI: 10.1016/j.carbon.2024.119768

Hongwei Bao , Qinghua Zhao , Yaping Miao , Yan Li , Hang Liu , Fei Ma

Although defects such as vacancies may degrade the in-plane mechanical properties of graphene and carbon nanotube (CNT), they may also promote interfacial crosslinking and load transfer, and thus enhance the mechanical behavior of graphene- and CNT-based composites. The balance between these effects is crucial for optimizing the design of graphene- and CNT-based composites. Herein, molecular dynamics simulations were constructed to unravel the effect of vacancy-induced interfacial crosslinking on the mechanical behaviors of graphene/CNT composites. Higher defect concentrations led to a higher density of sp³ C–C bonds at the interface, which reduced the tensile failure stress but increased the tensile failure strain. Meanwhile, the layer-by-layer failure transformed into a brittle failure. During compressive loading, the composites tended to buckle in the lower defect concentration range (<0.5 %) but exhibited outstanding buckling resistance at higher defect concentrations (5 %, 10 %). Shear loading led to wrinkling, and deformation instability was suppressed at the higher defect concentration, and all the composites demonstrated a layer-by-layer failure mode. Furthermore, the composites with a higher concentration of defects demonstrated excellent recoverable behavior during compressive loading. The results provide insights into the interface-dominated performance of graphene/CNT composites and help guide their design and fabrication.

虽然空位等缺陷可能会降低石墨烯和碳纳米管（CNT）的面内机械性能，但它们也可能促进界面交联和载荷传递，从而增强石墨烯和 CNT 复合材料的机械性能。这些效应之间的平衡对于优化石墨烯和 CNT 复合材料的设计至关重要。在此，我们构建了分子动力学模拟，以揭示空位诱导的界面交联对石墨烯/碳纳米管复合材料力学行为的影响。缺陷浓度越高，界面上的 sp3 C-C 键密度越高，从而降低了拉伸破坏应力，但增加了拉伸破坏应变。同时，逐层破坏转变为脆性破坏。在压缩加载过程中，复合材料在较低的缺陷浓度范围（0.5%）内倾向于屈曲，但在较高的缺陷浓度范围（5%、10%）内表现出出色的抗屈曲性。在较高的缺陷浓度下，剪切加载导致起皱，变形不稳定性受到抑制，所有复合材料都表现出逐层破坏模式。此外，缺陷浓度较高的复合材料在压缩加载过程中表现出优异的可恢复性。这些结果有助于深入了解石墨烯/碳纳米管复合材料以界面为主的性能，并为其设计和制造提供指导。

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引用次数: 0

Constructing the pyrolysis kinetic model of mesophase pitch for improving mechanical properties and thermal conductivity of carbon fibers 构建介相沥青热解动力学模型，改善碳纤维的机械性能和导热性能

IF 10.5 2区材料科学 Q1 CHEMISTRY, PHYSICAL

Carbon

Pub Date : 2024-10-29 DOI: 10.1016/j.carbon.2024.119765

Huang Wu , Gaoming Ye , Kui Shi , Dong Huang , Huafeng Quan , Chong Ye , Shipeng Zhu , Zhen Fan , Feng Qian , Hongbo Liu , Jinshui Liu

Mesophase pitch has become a superior precursor of high thermal conductivity pitch-based carbon fibers due to its high aromaticity, high carbon content and ability to be graphitized. However, mesophase pitch is prone to pyrolysis during melt spinning, which leads to structural defects such as pores in the carbon fiber, thus inhibiting the continuous improvement of carbon fiber properties. In this paper, a kinetic model was built by revealing the pyrolysis of petroleum-based mesophase pitch, establishing an association between pyrolysis weight loss and spinning process and spinning state. The results indicate that the pyrolysis products of petroleum-based mesophase pitch mainly consist of high-temperature volatile components and small molecules produced by continuous decomposition of macromolecules. When the pyrolysis weight loss of mesophase pitch is less than 2.2 wt%, it has good spinnability, and the surface and cross section of spun fiber are smooth and defect-free. Ultimately, the carbon fibers show a tensile strength of 3.09 GPa, a tensile modulus of 855 GPa, and a thermal conductivity of 727 W·m⁻¹·K⁻¹. It is demonstrated that the pyrolysis kinetics model of petroleum-based mesophase pitch is reliable for guiding the optimization of melt spinning processes and enhancing the physical properties of carbon fibers.

介相沥青具有高芳香度、高含碳量和石墨化能力，因此已成为高导热沥青基碳纤维的优质前体。然而，介相沥青在熔融纺丝过程中容易发生热解，导致碳纤维出现气孔等结构缺陷，从而阻碍了碳纤维性能的不断提高。本文通过揭示石油基间相沥青的热解过程，建立了热解失重与纺丝过程和纺丝状态之间的关联动力学模型。结果表明，石油基间相沥青的热解产物主要由高温挥发成分和大分子连续分解产生的小分子组成。介相沥青热解失重小于 2.2 wt%时，具有良好的可纺性，纺成的纤维表面和横截面光滑无缺陷。最终，碳纤维的拉伸强度为 3.09 GPa，拉伸模量为 855 GPa，导热系数为 727 W-m-1-K-1。研究表明，石油基间相沥青的热解动力学模型可用于指导熔融纺丝工艺的优化和提高碳纤维的物理性能。

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引用次数: 0

Development of graphitic and non-graphitic carbons using different grade biopitch sources 利用不同等级的生物沥青源开发石墨碳和非石墨碳

IF 10.5 2区材料科学 Q1 CHEMISTRY, PHYSICAL

Carbon

Pub Date : 2024-10-29 DOI: 10.1016/j.carbon.2024.119770

Bindu Antil , Yaseen Elkasabi , Gary D. Strahan , Randy L. Vander Wal

The growing demand for bio-renewable alternatives to fossil fuels in the production of sustainable carbon materials, aimed at reducing environmental impact, is crucial for advancing a greener future. This research explores an innovative approach for producing biopitches from bio-oils, which are subsequently utilized as a sustainable precursor for developing advanced graphitic carbons (GC) and non-graphitic carbons (NGC) through carbonization and graphitization processes. The study emphasizes the impact of the chemical composition of bio-oils and biopitches, including heteroatom structures, aromatic/aliphatic ratio, and oxygen content with oxygen-bearing functional groups, on the production of GC and NGC. The research also examines their structural parameters at various heating temperatures using characterization techniques such as X-ray diffraction (XRD), high-resolution transmission electron microscopy (HRTEM), and Raman spectroscopy. XRD analysis revealed that GC samples have lower interplanar spacing (d₀₀₂) and larger crystallite size than NGC, while Raman shows more short-range order and defects in NGC. Furthermore, HRTEM images and fringe analysis demonstrated differences in lamellae structures, tortuosity, and fringe length. These observations, unveiling differences in crystallite size and degree of graphitization between GC and NGC, underscore the influence of temperature on structural order and defect annealing, which is crucial for optimizing material properties.

在生产可持续碳材料的过程中，对化石燃料的生物可再生替代品的需求日益增长，这种替代品旨在减少对环境的影响，对于推动实现更加绿色的未来至关重要。本研究探索了一种从生物油中生产生物沟渠的创新方法，随后通过碳化和石墨化过程，将生物沟渠用作开发高级石墨碳（GC）和非石墨碳（NGC）的可持续前体。研究强调了生物油和生物沟渠的化学成分（包括杂原子结构、芳香族/脂肪族比例以及含氧官能团的氧含量）对生产 GC 和 NGC 的影响。研究还利用 X 射线衍射 (XRD)、高分辨率透射电子显微镜 (HRTEM) 和拉曼光谱等表征技术研究了它们在不同加热温度下的结构参数。X 射线衍射分析表明，与 NGC 相比，GC 样品的平面间距（d002）更小，晶粒尺寸更大，而拉曼光谱则显示 NGC 中存在更多的短程有序和缺陷。此外，HRTEM 图像和条纹分析表明了层状结构、扭曲度和条纹长度的差异。这些观察结果揭示了 GC 和 NGC 在晶粒大小和石墨化程度上的差异，强调了温度对结构有序性和缺陷退火的影响，这对优化材料性能至关重要。

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引用次数: 0

Preparation and characterization of high thermal conductive graphene films by improved reduction method 通过改进的还原法制备高导热石墨烯薄膜并确定其特性

IF 10.5 2区材料科学 Q1 CHEMISTRY, PHYSICAL

Carbon

Pub Date : 2024-10-28 DOI: 10.1016/j.carbon.2024.119769

Wenxiu Xu , Munan Lu , Yan Zhang , Ping Wang , Weibang Lyu , Yuanyuan Li

Structural defects such as voids and air pockets in graphene films resulting in a lower density of graphene films reduced the thermal conductivity of graphene films. However, removing the structural defects of graphene films through traditional thermal reduction methods always conducted under extremely high temperature. The energy consumption becomes a severe and inevitable problem. Herein, an energy-saving step-by-step improved thermal reduction method was developed to manufacture the high thermal conductive graphene films. Effect of graphene oxide (GO) mixing ratios of different sheet sizes on the thermal properties of hybrid graphene films were investigated. In addition, mixed large and small size sheet graphene/carboxylated cellulose nanocrystals composite films (LS-G/CNC) composite films were prepared to further repair defects and further improve the thermal properties. Results showed that the in-surface thermal conductivity increased from 177 W/mK to 269 W/mK with an increase of approximately 52 % through step-by-step improved thermal reduction method. The mixed size sheet also increased the thermal conductivity of LS-G films to 607 W/mk. The small size sheet graphene oxide (SGO) filled the voids of the large size sheet graphene oxide (LGO). Finally, CNC was further used to fill the carbon atom vacancies in the thermal reduction process and improved the graphitization of the composite films. LS-G/CNC composite films without structural defects exhibited high thermal conductivity of 852 W/mk and electrical conductivity of 7.1 × 10⁴ S/m.

石墨烯薄膜中的空隙和气穴等结构缺陷导致石墨烯薄膜密度降低，从而降低了石墨烯薄膜的热导率。然而，通过传统的热还原方法去除石墨烯薄膜的结构缺陷总是在极高的温度下进行。能耗成为一个不可避免的严重问题。在此，我们开发了一种节能的分步改进热还原法来制造高导热石墨烯薄膜。研究了不同片状尺寸的氧化石墨烯（GO）混合比对混合石墨烯薄膜热性能的影响。此外，还制备了大尺寸和小尺寸混合片状石墨烯/羧基纤维素纳米晶（LS-G/CNC）复合薄膜，以进一步修复缺陷，进一步提高热性能。结果表明，通过逐步改进的热还原方法，表面内导热系数从 177 W/mK 提高到 269 W/mK，提高了约 52%。混合尺寸薄片也将 LS-G 薄膜的热导率提高到了 607 W/mk。小尺寸片状氧化石墨烯（SGO）填补了大尺寸片状氧化石墨烯（LGO）的空隙。最后，CNC 被进一步用于填补热还原过程中的碳原子空位，提高了复合薄膜的石墨化程度。无结构缺陷的 LS-G/CNC 复合薄膜的热导率高达 852 W/mk，电导率为 7.1 × 104 S/m。

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引用次数: 0

Emerging 2D MXene quantum dots for catalytic conversion of CO2 催化转化二氧化碳的新兴二维 MXene 量子点

IF 10.5 2区材料科学 Q1 CHEMISTRY, PHYSICAL

Carbon

Pub Date : 2024-10-28 DOI: 10.1016/j.carbon.2024.119758

Nadeem Hussain Solangi , Lakshmi Prasanna Lingamdinne , Rama Rao Karri , Nabisab Mujawar Mubarak , Shaukat Ali Mazari , Janardhan Reddy Koduru

MXene is an emerging material for converting carbon dioxide (CO₂) into valuable products because of its robust physical and chemical properties. The high specific surface area (SSA), conductivity, and stability of the MXene make it an attractive material for the catalytic conversion of CO₂. The pristine MXene possessed poor catalytic properties as compared to their composites. This study briefly discussed the magical properties and advanced synthesizing routes of MXene and MXene quantum dots (MQDs). In addition, the oxidation of the MXene is responsible for altering its chemical composition, and the factors used to oxidize the MXene were discussed in detail. Furthermore, the mechanism of hydrogenation, chemical, electrocatalytic, and photocatalytic reduction of CO₂ has been discussed. Finally, the MXene quantum dots (MQDs) for photocatalytic conversion of CO₂ for the first time also present the future challenges and prospectus associated with MXene.

由于其强大的物理和化学特性，MXene 是一种将二氧化碳（CO2）转化为有价值产品的新兴材料。MXene 的高比表面积（SSA）、导电性和稳定性使其成为催化转化 CO2 的一种极具吸引力的材料。与它们的复合材料相比，原始的 MXene 催化性能较差。本研究简要讨论了 MXene 和 MXene 量子点 (MQDs) 的神奇特性和先进的合成路线。此外，还详细讨论了氧化 MXene 可改变其化学成分，以及氧化 MXene 的因素。此外，还讨论了二氧化碳的氢化、化学、电催化和光催化还原机制。最后，还首次介绍了用于光催化转化二氧化碳的 MXene 量子点（MQDs），并展望了与 MXene 相关的未来挑战和前景。

引用次数: 0

Investigation into shear-thinning behavior in wet spinning of carbon nanotube fibers modeled by power law viscosity model 用幂律粘度模型研究碳纳米管纤维湿法纺丝中的剪切稀化行为

IF 10.5 2区材料科学 Q1 CHEMISTRY, PHYSICAL

Carbon

Pub Date : 2024-10-28 DOI: 10.1016/j.carbon.2024.119766

Jaegyun Im , Min Chan Kim , Chanwoo Park , Yun Ho Jeong , Beomjin Jeong , Kyu Hyun , Jaegeun Lee

The wet spinning of carbon nanotube (CNT) fibers, a representative solution processing of CNTs, has been advanced through the integration of well-established polymer sciences into their field. However, the flow behavior of CNT dispersions in the narrow spinning line, where its characteristics undergo changes due to the high-shear rate regime, has not been utilized to determine their spinnability, despite being a commonly employed method in the wet spinning of polymer fibers. Herein, we employed the power law viscosity model to investigate the correlation between flow behavior and the spinnability of CNT dispersion through the power law index which approaches to 0 as the shear-thinning behavior strengthens. We suggest that the spinnability of CNT dispersion is proportional to the degree of shear-thinning behavior of the dispersion. We ascribe this correlation to the integrity of CNT fibers which predominantly rely on the strong van der Waals forces between CNTs. These findings offer new insights into the role of fiber integrity in spinnability and provide a framework for optimizing the wet spinning process of CNT fibers through detailed analysis of dispersion flow behavior.

碳纳米管（CNT）纤维的湿法纺丝是 CNT 的一种代表性溶液加工方法，通过将成熟的聚合物科学融入其领域，该方法得到了进一步发展。然而，尽管碳纳米管分散体是聚合物纤维湿法纺丝中常用的方法，但其在窄纺丝生产线上的流动行为却未被用于确定其可纺性。在此，我们采用幂律粘度模型，通过幂律指数（随着剪切稀化行为的加强，幂律指数趋近于 0）来研究流动行为与 CNT 分散体可纺性之间的相关性。我们认为，碳纳米管分散体的可纺性与分散体的剪切稀化程度成正比。我们将这种相关性归因于碳纳米管纤维的完整性，这种完整性主要依赖于碳纳米管之间强大的范德华力。这些发现为了解纤维完整性在可纺性中的作用提供了新的视角，并为通过详细分析分散流动行为来优化 CNT 纤维的湿法纺丝工艺提供了框架。

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引用次数: 0

Rapid construction of robust and hydrophilic lignin-derived laser-induced graphene electrodes using PVA-free dopants 使用不含 PVA 的掺杂剂快速构建坚固耐用的亲水性木质素激光诱导石墨烯电极

IF 10.5 2区材料科学 Q1 CHEMISTRY, PHYSICAL

Carbon

Pub Date : 2024-10-28 DOI: 10.1016/j.carbon.2024.119767

Anyi Wen, Chengkai Wang, Jieying Nong, Chengguo Hu

Polyvinyl alcohol (PVA) binder can efficiently improve the quality of lignin-derived laser-induced graphene (LIG), which however also leads to the poor production efficiency and mechanical property of LIG electrodes, due to its slow dissolution rate in water and full decomposition during laser scribing. To address this issue, a new doping strategy for sodium lignosulphonate (SL) precursors using three co-dopants, i.e., polyvinyl pyrrolidone-10 (PVP-10), Tween-20 and ferric chloride (FeCl₃), is proposed. Among these dopants, PVP effectively enhances the adhesion of SL-based LIG (SL-LIG) to plastic substrates, Tween-20 facilitates the spreading of PVP-doped SL precursor solution on hydrophobic substrates to form uniform coatings, while FeCl₃ improves the conductivity of SL-LIG. The combination of these dopants produces a new SL precursor solution with high water solubility and excellent film formation ability, which enables the rapid mass production of robust and hydrophilic LIG electrodes on various plastic substrates without any pretreatment. The resulting LIG electrodes possess wide potential windows, low capacitive background and tunable electrochemical activity, which thus establish a green route to the scalable construction of graphene-based electrochemical sensors with high efficiency, high performance and low cost.

聚乙烯醇（PVA）粘合剂可有效提高木质素衍生激光诱导石墨烯（LIG）的质量，但由于其在水中的溶解速度较慢，且在激光划片过程中会完全分解，因此也导致 LIG 电极的生产效率和机械性能较差。为解决这一问题，我们提出了一种新的木质素磺酸钠（SL）前驱体掺杂策略，使用三种辅助掺杂剂，即聚乙烯吡咯烷酮-10（PVP-10）、吐温-20 和氯化铁（FeCl3）。在这些掺杂剂中，聚乙烯吡咯烷酮能有效增强基于 SL 的 LIG（SL-LIG）对塑料基底的附着力，吐温-20 能促进掺杂聚乙烯吡咯烷酮的 SL 前驱体溶液在疏水性基底上铺展形成均匀的涂层，而三氯化铁则能提高 SL-LIG 的导电性。这些掺杂剂的结合产生了一种具有高水溶性和出色成膜能力的新型 SL 前驱体溶液，从而无需任何预处理就能在各种塑料基底上快速批量生产坚固的亲水性 LIG 电极。所制备的石墨烯电极具有宽电位窗口、低电容背景和可调的电化学活性，从而为高效、高性能和低成本地构建可扩展的石墨烯基电化学传感器开辟了一条绿色通道。

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引用次数: 0

Microcrystalline cellulose-derived hard carbon for robust and low-potential sodium storage 提取自微晶纤维素的硬碳，可实现稳健的低电位钠储存

IF 10.5 2区材料科学 Q1 CHEMISTRY, PHYSICAL

Carbon

Pub Date : 2024-10-28 DOI: 10.1016/j.carbon.2024.119771

Chen Sun , Fei Gao , Jun-Yang Wu , Yiqiao Yang , Qiang Sun

Developing hard carbon with unique and regulable microstructure is the key for the development of sodium ion batteries (SIBs), while the poor low-potential sodium storage property as well as ambiguous sodium storage mechanism arising from the intricate pseudo-graphitic and graphite-like structures present a great challenge to the commercialization of SIBs. Herein, microcrystalline cellulose was proposed as carbon precursor to synthesis hard carbons by controlling carbonization temperature. As expected, the resulting hard carbons simultaneously contained pseudo-graphitic and graphite-like structures, and in situ XRD analysis suggested that a larger interlayer spacing of pseudo-graphitic structure facilitated Na⁺ insertion, whereas smaller spacing of graphite-like structure could enhance the electrical conductivity. As a result of the optimized carbonization temperature of 1400 °C, the obtained hard carbon with larger interlayer spacing, reduced defect sites, and more closed pores, displayed an initial discharge capacity of 376.7 mA h g⁻¹ with low-potential plateau capacity ratio of 57.58 % and a high initial Coulomb efficiency of 84.32 %, while an increased plateau capacity ratio of 63.91 % in the second discharge process using an ester-based electrolyte.

开发具有独特可调微观结构的硬质碳是钠离子电池（SIB）开发的关键，而错综复杂的伪石墨和类石墨结构导致的低电位储钠性能差、储钠机理不明确等问题给钠离子电池的商业化带来了巨大挑战。本文提出以微晶纤维素为碳前驱体，通过控制碳化温度合成硬质碳。原位 XRD 分析表明，较大的假石墨结构层间距有利于 Na+ 的插入，而较小的类石墨结构层间距则可提高导电性。由于碳化温度优化为 1400 °C，获得的硬碳具有更大的层间距、更少的缺陷位点和更封闭的孔隙，其初始放电容量为 376.7 mA h g-1，低电位高原容量比为 57.58 %，初始库仑效率高达 84.32 %，而在使用酯基电解质的第二次放电过程中，高原容量比提高了 63.91 %。

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引用次数: 0

Multifunctional composite phase change material with electrostatic self-assembly structure based on carboxylated multi-walled carbon nanotubes 基于羧基多壁碳纳米管的具有静电自组装结构的多功能复合相变材料

IF 10.5 2区材料科学 Q1 CHEMISTRY, PHYSICAL

Carbon

Pub Date : 2024-10-26 DOI: 10.1016/j.carbon.2024.119763

Silong Wang , Shengsi Wang , Dengji Xu , Hongyuan Ding , Jianghui Xie , Yi Jiang , Changcheng Liu , Que Huang

The need for improved thermal regulation in electronic devices and solar thermal energy storage, prompted by the energy crisis, has expedited the advancement of phase change materials (PCMs). Carboxylated multi-walled carbon nanotubes (MWCNT-COOH) were produced by introducing carboxyl functional groups onto MWCNTs utilizing a concentrated acid treatment. The novel composite was engineered through an electrostatic self-assembly process between the negatively charged MWCNT-COOH and the positively charged Poly dimethyl diallyl ammonium chloride (PDDA) solution, filling the structure with the PCM polyethylene glycol (PEG) and incorporating the (magnesium hydrate) Mg(OH)₂ to enhance the material's flame resistance at high temperatures. The thermal conductivity of the obtained composites improved significantly from 0.25 W/m·K to 1.183 W/m·K, while maintaining an enthalpy of phase transition of phase change of 135.1 J/g. Owing to the capillary effect of the closely packed MWCNT-COOH tubular structure, the composite material exhibited excellent high-temperature shape retention ability. Additionally, the composite demonstrated high absorption with an absorbance reaching 1.18 L/(g·cm) and composite materials can convert up to 86.8 % of light energy into heat energy.

在能源危机的推动下，电子设备和太阳能热能储存对改善热调节的需求加速了相变材料（PCMs）的发展。羧基化多壁碳纳米管（MWCNT-COOH）是利用浓酸处理在多壁碳纳米管上引入羧基官能团而制成的。通过带负电荷的 MWCNT-COOH 与带正电荷的聚二甲基二烯丙基氯化铵（PDDA）溶液之间的静电自组装过程，在结构上填充 PCM 聚乙二醇（PEG），并加入（水合镁）Mg(OH)2 以增强材料在高温下的阻燃性，从而设计出新型复合材料。所得复合材料的导热系数从 0.25 W/m-K 显著提高到 1.183 W/m-K，同时相变的相变焓保持在 135.1 J/g。由于紧密排列的 MWCNT-COOH 管状结构的毛细管效应，复合材料表现出优异的高温形状保持能力。此外，该复合材料还具有高吸收性，吸收率达到 1.18 L/（g-cm），复合材料可将高达 86.8% 的光能转化为热能。

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引用次数: 0

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