Carbon最新文献 - Book学术

Atomically tailored heteroatom-doped hard carbon from structure-engineered coordination-crosslinked polymers for potassium-ion storage 结构工程配位交联聚合物中原子定制杂原子掺杂硬碳用于钾离子存储

IF 11.6 2区材料科学 Q1 CHEMISTRY, PHYSICAL

Carbon

Pub Date : 2026-01-28 DOI: 10.1016/j.carbon.2026.121317

Chunlei Chi , Guanwen Wang , Xinhou Yang , Bin Qi , Zhiyuan Li , Baoyi Mu , Zheng Liu , Tong Wei , Guojun Xu , Zhuangjun Fan

Hard carbon (HC) possesses large interlayer spacing, abundant defects, and porous structures, enabling efficient storage of large-radius K⁺ ions. Nevertheless, its highly disordered nature renders the microstructure challenging to precisely regulate, which disrupts electronic conductivity and introduces irreversible active sites. Herein, conjugated poly(bithiophene) and phytic acid were employed as ligands to construct a lamellar precursor with reinforced interlayer support through Fe³⁺ coordination and crosslinking. Upon optimized pyrolysis, the derived HC exhibits a high reversible capacity of 407 mAh g⁻¹, long-term cycling stability (1800 cycles at 1 A g⁻¹), and excellent rate capability (200 mAh g⁻¹ at 1 A g⁻¹) in potassium-ion batteries. Thermogravimetry-mass spectrometry (TG-MS) analysis was conducted to investigate the structural evolution mechanisms of the precursor during pyrolysis. Furthermore, ex-situ characterization combined with density functional theory (DFT) calculations elucidated the intrinsic origin of the superior reversibility and activity associated with S–C and P–C doped configuration. These findings offer new insights into precursor engineering and controlled heteroatom doping for the development of high-performance HC anodes, providing both fundamental understanding and practical guidance for next-generation energy storage and conversion.

硬碳（HC）具有较大的层间距、丰富的缺陷和多孔结构，能够有效地储存大半径K+离子。然而，其高度无序的性质使其微观结构难以精确调节，这会破坏电子导电性并引入不可逆活性位点。本文以共轭聚二噻吩和植酸为配体，通过Fe3+配位和交联，构建了层间支撑增强的层状前驱体。经过优化的热解，得到的HC在钾离子电池中具有407 mAh g−1的高可逆容量，长期循环稳定性（在1 a g−1下循环1800次）和优异的倍率容量（在1 a g−1下200mah g−1）。采用热重质谱（TG-MS）分析了前驱体在热解过程中的结构演化机制。此外，非原位表征结合密度泛函理论（DFT）计算阐明了与S-C和P-C掺杂构型相关的优越可逆性和活性的内在起源。这些发现为开发高性能HC阳极提供了前体工程和受控杂原子掺杂的新见解，为下一代能量存储和转换提供了基础理解和实践指导。

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引用次数: 0

Vanadium-doped cobalt selenide nanoparticles embedded in mesoporous hollow carbon spheres as highly efficient bifunctional electrocatalyst for rechargeable Zn-air batteries 含钒硒化钴纳米颗粒嵌入介孔中空碳球中作为可充电锌空气电池的高效双功能电催化剂

IF 11.6 2区材料科学 Q1 CHEMISTRY, PHYSICAL

Carbon

Pub Date : 2026-01-28 DOI: 10.1016/j.carbon.2026.121318

Sungkyun Cheong, Jaehun Shin, Siyeon Kang, Sang Eun Shim, Kyeongseok Min, Sung-Hyeon Baeck

The growing demand for sustainable energy has brought rechargeable Zn-air batteries (ZABs) into focus due to their high energy density and low cost. However, their performance is severely hindered by sluggish oxygen electrocatalysis at the air cathode. Herein, we report the rational design and synthesis of a vanadium-doped cobalt diselenide embedded in a mesoporous hollow carbon sphere framework (V–CoSe₂@MHCS) via a sol-gel templating, vacuum impregnation, and thermal selenization process. The hierarchical hollow carbon architecture ensures efficient mass transport and abundant active site exposure, while vanadium incorporation modulates the electronic structure of CoSe₂, generating defect-rich surfaces and enhancing intrinsic redox activity. Benefiting from these synergistic structural and electronic features, V–CoSe₂@MHCS exhibits outstanding bifunctional electrocatalytic activities. Based on the electrocatalytic performance test using Hg/HgO (1.0 M KOH) reference electrode, the prepared electrocatalyst shows low overpotential of 342 mV at 10 mA cm⁻² for oxygen evolution reaction (OER) and a high half-wave potential of 0.825 V for oxygen reduction reaction (ORR). When applied as the air cathode in aqueous ZAB, V–CoSe₂@MHCS delivers a high specific capacity of 732.5 mAh g_Zn⁻¹, a peak power density of 154.8 mW cm⁻², and exceptional long-term cycling stability. Furthermore, when integrated into a quasi-solid-state flexible ZAB, the catalyst demonstrates exceptional electrochemical performance and a stable output under repeated bending conditions. The device achieves a high current density of 173.4 mA cm⁻² at 0.3 V and a peak power density of 65.2 mW cm⁻², and demonstrating stable cycling performance over 70 cycles.

对可持续能源日益增长的需求使可充电锌空气电池（ZABs）因其高能量密度和低成本而成为人们关注的焦点。然而，空气阴极的氧电催化缓慢严重阻碍了它们的性能。在此，我们报告了通过溶胶-凝胶模板，真空浸渍和热硒化工艺，合理设计和合成了嵌入在介孔中空碳球框架（V - CoSe2@MHCS）中的钒掺杂钴二硒化物。分层中空碳结构确保了高效的质量传递和丰富的活性位点暴露，而钒的加入调节了CoSe2的电子结构，产生了富含缺陷的表面，增强了内在的氧化还原活性。得益于这些协同结构和电子特性，V - CoSe2@MHCS表现出出色的双功能电催化活性。采用Hg/HgO （1.0 M KOH）参比电极进行电催化性能测试，制备的电催化剂在10 mA cm−2下的析氧反应（OER）过电位为342 mV，氧还原反应（ORR）半波电位为0.825 V。当用作ZAB水溶液中的空气阴极时，V - CoSe2@MHCS提供732.5 mAh gZn−1的高比容量，154.8 mW cm−2的峰值功率密度，以及出色的长期循环稳定性。此外，当集成到准固态柔性ZAB中时，催化剂表现出优异的电化学性能，并且在反复弯曲条件下具有稳定的输出。该器件在0.3 V电压下具有173.4 mA cm−2的高电流密度和65.2 mW cm−2的峰值功率密度，并且在70次循环中表现出稳定的循环性能。

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引用次数: 0

Spatially varying wettability and resistivity in laser-induced graphene for flexible microfluidics, programmable heaters, and thermochromic displays 用于柔性微流体、可编程加热器和热致变色显示器的激光诱导石墨烯的空间变化润湿性和电阻率

IF 11.6 2区材料科学 Q1 CHEMISTRY, PHYSICAL

Carbon

Pub Date : 2026-01-28 DOI: 10.1016/j.carbon.2026.121304

Mirza Sahaluddin , Moataz Abdulhafez , Soumalya Ghosh , Mostafa Bedewy

Flexible microfluidic systems and patterned heaters are critical for applications ranging from point-of-care diagnostics and wearable thermotherapy to de-icing and thermochromic displays, yet most existing platforms rely on multi-step fabrication, metal integration, or external addressing electronics. Here, we present a purely laser-based, single-process strategy to spatially program wettability and resistivity in laser-induced graphene (LIG) on polyimide. By combining controlled beam defocus with multiple laser passes, we define adjacent single-pass (R1) and double-pass (R2) LIG regions with similar porous morphologies and Raman signatures, yet markedly different surface and electrical properties. Specifically, R1 exhibits near-complete wetting (contact angle <7°), while R2 is comparatively more hydrophobic, and the sheet resistance is reduced to 12 Ω/□ in R2. The contrast is tuned via the raster gap between laser scan lines, with an optimal gap of 356 μm maximizing property differences without compromising continuity. This spatial contrast enables pump-free capillary-driven microfluidic transport, including vertical flow against gravity, as well as programmable electrothermal behavior, with temperature differences exceeding 50 °C between R1 and R2 under a single bias voltage. A three-dimensional finite element model incorporating volumetric Joule heating and convective–radiative losses accurately reproduces the measured infrared temperature distributions. Finally, integration of commercial thermochromic pigments yields a flexible thermochromic display in which discrete pixels are addressed solely by the underlying LIG resistivity pattern, without additional electrodes or control circuitry. This work establishes a scalable, maskless route to all-carbon, self-reporting flexible devices that integrate fluidic, thermal, and visual functionality through spatially programmed laser processing.

灵活的微流体系统和图形加热器对于从护理点诊断和可穿戴热疗法到除冰和热致变色显示器的应用至关重要，但大多数现有平台依赖于多步骤制造，金属集成或外部寻址电子设备。在这里，我们提出了一种纯粹基于激光的单工艺策略，用于对聚酰亚胺上激光诱导石墨烯（LIG）的润湿性和电阻率进行空间编程。通过将受控光束离焦与多个激光通道相结合，我们定义了相邻的单通道（R1）和双通道（R2） LIG区域，它们具有相似的多孔形态和拉曼特征，但表面和电学性质明显不同。其中，R1表现出接近完全润湿（接触角<；7°），而R2相对来说更疏水，R2的片材电阻降低到12 Ω/□。对比度通过激光扫描线之间的光栅间隙来调节，最佳间隙为356 μm，最大限度地提高了性能差异，同时又不影响连续性。这种空间对比使无泵毛细管驱动的微流体传输成为可能，包括重力垂直流动，以及可编程的电热行为，在单个偏置电压下，R1和R2之间的温差超过50°C。结合体积焦耳加热和对流辐射损耗的三维有限元模型准确地再现了测量到的红外温度分布。最后，商业热致变色颜料的集成产生了一种柔性热致变色显示器，其中离散像素仅由底层LIG电阻率模式处理，无需额外的电极或控制电路。这项工作建立了一个可扩展的、无掩膜的全碳、自我报告的柔性设备，通过空间编程的激光加工集成了流体、热和视觉功能。

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引用次数: 0

High-electronegativity O-triggered vacancy defects and ionic channels in N-doped carbon-confined amorphous Mo–O clusters for high-performance potassium-ion hybrid capacitors 高性能钾离子杂化电容器中n掺杂碳约束非晶Mo-O团簇的高电负性o触发空位缺陷和离子通道

IF 11.6 2区材料科学 Q1 CHEMISTRY, PHYSICAL

Carbon

Pub Date : 2026-01-27 DOI: 10.1016/j.carbon.2026.121314

Taiyang Wang , Fanyan Zeng , Wenxiu He , Jiaqi Li , Hongbo Huang , Dui Ma , Yang Pan

The performance of potassium-ion hybrid capacitors (PIHCs) is hindered by insufficient electroactive sites and sluggish charge transfer in anodes. Herein, this work proposes a high-electronegativity O-mediated amorphization strategy to construct N-doped carbon-confined amorphous Mo–O clusters (Mo–O@NC). Compared with N- or C-coordinated analogues (Mo–N@NC and Mo–C@NC), the strongly bonded O (χ = 3.44) markedly modulates the local environment of Mo, inducing pronounced electron redistribution. This process generates abundant unsaturated vacancy defects and isotropic ion transport channels in the clusters and at their interfaces. Theoretical calculations reveal that high-electronegativity O optimizes K⁺ adsorption energy, broadens available adsorption sites, and upshifts the d-band center of Mo. These effects collectively promote charge transfer and establish a highly active “electron reservoir.” Electrochemically, the Mo–O@NC anode delivers a high reversible capacity of 529.5 mAh g⁻¹ at 0.1 A g⁻¹ and retains 231.3 mAh g⁻¹ after 3000 cycles at 5.0 A g⁻¹, accompanied by a high capacitive contribution and low charge-transfer resistance, significantly outperforming its counterparts. The assembled PIHCs achieve remarkable energy/power densities (211.2 Wh kg⁻¹/10015 W kg⁻¹), with a capacity decay of only 0.0022 % per cycle. This study offers a novel design strategy for high-performance electrodes for metal ion storage via high-electronegativity O-triggered amorphization.

钾离子混合电容器（pihc）的性能受到电活性位点不足和阳极电荷转移缓慢的阻碍。在此，本研究提出了一种高电负性o介导的非晶化策略来构建n掺杂碳约束的非晶Mo - o簇（Mo - O@NC）。与N-或c -配位类似物（Mo - N@NC和Mo - C@NC）相比，强键O （χ = 3.44）显著调节Mo的局部环境，诱导明显的电子重分布。这一过程在团簇及其界面处产生了丰富的不饱和空位缺陷和各向同性离子输运通道。理论计算表明，高电负性的O优化了K+的吸附能，拓宽了可用的吸附位点，并提升了Mo的d带中心。这些效应共同促进了电荷转移，并建立了一个高活性的“电子库”。在电化学上，Mo - O@NC阳极在0.1 a g - 1下提供529.5 mAh g - 1的高可逆容量，在5.0 a g - 1下循环3000次后保持231.3 mAh g - 1，同时具有高电容贡献和低电荷转移电阻，显著优于同类阳极。组装的pihc实现了显著的能量/功率密度（211.2 Wh kg−1/10015 W kg−1），每周期容量衰减仅为0.0022%。本研究通过高电负性o触发非晶化为高性能金属离子存储电极提供了一种新的设计策略。

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引用次数: 0

CeOx-functionalized Pd nanoparticles on single-walled carbon nanotubes for alkaline hydrogen oxidation reaction 单壁碳纳米管上氧化铈功能化钯纳米粒子的碱性氢氧化反应

IF 11.6 2区材料科学 Q1 CHEMISTRY, PHYSICAL

Carbon

Pub Date : 2026-01-27 DOI: 10.1016/j.carbon.2026.121313

Farhan S.M. Ali , Lanna E.B. Lucchetti , Med Amine Hammouali , Eeva-Leena Rautama , Jani Sainio , Hua Jiang , Lilian Moumaneix , Antti-Jussi Kallio , Olli Sorsa , Simo Huotari , Ramesh K. Singh , Dario R. Dekel , Samira Siahrostami , Tanja Kallio

The sluggish kinetics of hydrogen oxidation reaction (HOR) in alkaline electrolytes highlight the strong need to develop next-generation catalyst materials for anion-exchange membrane fuel cells (AEMFC) anodes. In this study, CeO_x is sequentially deposited on Pd nanoparticles supported on single-walled carbon nanotubes (SWNT) via atomic layer deposition (ALD). The obtained Pd@CeO_x SWNT_{16 ALD cycles} catalyst shows an excellent alkaline HOR performance with a specific exchange current of 166 mA mg⁻¹_Pd. This is three times higher than the commercially available Pd catalyst and the highest among reported Pd/CeO_x catalyst materials with different CeO_x overlayer coverages. By combining the X-ray diffraction, X-ray photoelectron spectroscopy, X-ray absorption spectroscopy and high-resolution scanning transmission electron microscopy, we confirm that the activity improvement is due to the highly conductive SWNT support enabling the fabrication of high surface area Pd clusters and CeO_x overlayer. These methods reveal that the oxidation state of Ce is varying from Ce³⁺ to Ce⁴⁺ in relation to the CeO_x overlayer thickness and the number of ALD cycles. Density functional theory calculations show that the presence of Ce/CeO_x increases the diversity and population of Pd active sites with improved activity in its vicinity leading to enhanced overall catalytic performance. Moreover, this work provides a new perspective to develop highly active alkaline HOR catalysts for AEMFC.

碱性电解质中氢氧化反应（HOR）的缓慢动力学凸显了开发下一代阴离子交换膜燃料电池（AEMFC）阳极催化剂材料的迫切需要。在本研究中，通过原子层沉积（ALD）将CeOx依次沉积在单壁碳纳米管（SWNT）上的Pd纳米颗粒上。所得Pd@CeOx SWNT16 ALD循环催化剂具有良好的碱性HOR性能，比交换电流为166 mA mg−1Pd。这比市售的钯催化剂高出三倍，也是目前报道的具有不同氧化铈覆盖层的钯/氧化铈催化剂材料中最高的。通过结合x射线衍射、x射线光电子能谱、x射线吸收能谱和高分辨率扫描透射电子显微镜，我们证实了活性的提高是由于高导电性的SWNT支撑使得高表面积Pd团簇和CeOx覆盖层的制造成为可能。结果表明，Ce3+和Ce4+的氧化态随CeOx层厚度和ALD循环次数的变化而变化。密度泛函理论计算表明，Ce/CeOx的存在增加了Pd活性位点的多样性和数量，提高了其附近活性，从而提高了整体催化性能。此外，本研究为开发AEMFC高活性碱性HOR催化剂提供了新的思路。

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引用次数: 0

Mesoporous bowl-in-ball carbon microspheres for lightweight and high-performance microwave absorption 介孔碗中球碳微球轻量化和高性能的微波吸收

IF 11.6 2区材料科学 Q1 CHEMISTRY, PHYSICAL

Carbon

Pub Date : 2026-01-25 DOI: 10.1016/j.carbon.2026.121312

Yan Cheng , Kai Zhou , Yongzhen Ma , Yufu Gao , Shuzhen Wang , Hongkui Li , Guochi Li , Huanqin Zhao , Tong Wang , Haibo Yang

Carbon-based microwave absorbers have been widely investigated due to the low density and tunable dielectric properties, but the limited loss capability and narrow absorption bandwidth are still remain to be solved. In this work, we present a novel structural design—mesoporous bowl-in-ball carbon microsphere (BIBC), composed of a hollow carbon ball encapsulating a mesoporous carbon bowl, to achieve lightweight and high-performance microwave absorption (MA). This unique configuration integrates symmetric-asymmetric structural combination to let microwave in and then being dissipated. By regulating the inner carbon shell thickness, the morphology evolves from double-wall hollow spheres to bowl-in-ball microsphere. The optimized BIBC-2 exhibited a broad effective absorption bandwidth (EAB) of 7.1 GHz at 2.7 mm and a strong reflection loss (RL) of −54.0 dB, which is ascribed to the unique structure bringing about the balance between impedance matching and attenuation capability. Radar cross-section (RCS) simulations was further conducted to confirm its superior absorption performance in practical scenarios. This study paves a new way for designing lightweight and efficient microwave absorbers through structural engineering design.

碳基微波吸收材料由于其低密度和可调谐的介电特性而得到了广泛的研究，但其有限的损耗能力和狭窄的吸收带宽仍有待解决。在这项工作中，我们提出了一种新的结构设计-介孔碗中碳微球（BIBC），由中空碳球封装介孔碳碗组成，以实现轻量化和高性能的微波吸收（MA）。这种独特的配置集成了对称和非对称的结构组合，让微波进入然后消散。通过调节内碳壳厚度，使其由双壁空心球演变为球中碗状微球。优化后的BIBC-2在2.7 mm处具有7.1 GHz的宽有效吸收带宽（EAB）和- 54.0 dB的强反射损耗（RL），这是由于其独特的结构在阻抗匹配和衰减能力之间取得了平衡。进一步进行了雷达截面（RCS）仿真，验证了其在实际场景下优越的吸收性能。本研究通过结构工程设计为设计轻量化、高效的微波吸收器开辟了新途径。

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引用次数: 0

The influence of pitch oxidation temperature on the structure and electrochemical properties of derived activated carbon 沥青氧化温度对衍生活性炭结构和电化学性能的影响

IF 11.6 2区材料科学 Q1 CHEMISTRY, PHYSICAL

Carbon

Pub Date : 2026-01-24 DOI: 10.1016/j.carbon.2026.121311

Yaorong Hu , Shijie Wu , Yan Song , Tao Yang , Haoyang Wu , Ning Zhao , Zhanjun Liu

Pre-oxidation is an effective route for producing high-surface-area activated carbons, yet the role of oxidation temperature in pore development remains unclear. This work prepared pitch-derived activated carbons via pre-oxidation at 290 °C and 350 °C followed by steam activation, investigating the temperature-dependent evolution of oxygen functional groups and porosity. Results reveal that oxidation at 290 °C primarily attacks aliphatic side chains, forming C–O groups, while 350 °C promotes oxygen radical attack on aromatic C–H bonds, increasing cross-linking C(O)–O groups. This cross-linked structure inhibits carbon layer rearrangement during pre-carbonization, exposing defective sites conducive to pore formation. Concurrently, three-dimensional crosslinking and gas release from condensed oxygen groups creates steam channels, enhancing mesopore development. OP-290-AC exhibits a specific surface area of 1252 m² g⁻¹ with 68.57 % mesopores, whereas OP-350-AC achieves 1665 m² g⁻¹ and 89.72 % mesopores. As a cathode in potassium-ion hybrid capacitors, OP-350-AC's high mesoporosity facilitates rapid ion transport, improving rate capability, while its suitable surface chemistry contributes additional pseudo capacitance. The assembled OP-290-800//OP-350-AC device delivers a power density of 185.4 W kg⁻¹ at 74.0 Wh kg⁻¹. This work provides a theoretical and technical framework for pore-structure control and application-specific optimization of activated carbons.

预氧化是制备高表面积活性炭的有效途径，但氧化温度在孔隙发育中的作用尚不清楚。本研究通过290°C和350°C的预氧化和蒸汽活化制备沥青衍生活性炭，研究了氧官能团和孔隙度的温度依赖性演变。结果表明，290°C氧化主要攻击脂肪侧链，形成C -O基团，而350°C氧化促进氧自由基攻击芳香C - h键，增加交联C(O) -O基团。这种交联结构在预碳化过程中抑制碳层重排，暴露出有利于孔隙形成的缺陷位点。同时，三维交联和气体从缩合氧基团释放形成蒸汽通道，促进中孔发育。OP-290-AC的比表面积为1252 m2 g−1，介孔率为68.57%，OP-350-AC的比表面积为1665 m2 g−1，介孔率为89.72%。作为钾离子混合电容器的阴极，OP-350-AC的高介孔有利于离子的快速传输，提高了速率能力，同时其合适的表面化学性质有助于额外的伪电容。装配后的OP-290-800//OP-350-AC设备在74.0 Wh kg - 1时的功率密度为185.4 W kg - 1。本研究为活性炭的孔结构控制和应用优化提供了理论和技术框架。

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引用次数: 0

Constructing dual networks in tissue-paper-derived carbon nanofiber/Co@C composites toward exceptional microwave absorption and heat conduction 在组织纸衍生碳纳米纤维/Co@C复合材料中构建双网络以实现优异的微波吸收和热传导

IF 11.6 2区材料科学 Q1 CHEMISTRY, PHYSICAL

Carbon

Pub Date : 2026-01-24 DOI: 10.1016/j.carbon.2026.121305

Peiwen Wang , Liujia Bian , Junyan Jiang , Pinzhang Zhao , Xiaojuan Wang , Liyan Xie , Guoxiu Tong , Wenhua Wu

To simultaneously tackle the critical issues of electromagnetic (EM) interference and heat accumulation in electronics, tissue-paper-derived carbon fiber (CF)@Co@C composites with a dual network were first synthesized as an advanced bifunctional filler through a facile impregnation-annealing process. The incorporation of CFs with Co@C foams can construct dual networks, multiple heterointerfaces, magnetic-dielectric dual-losses, and electron-phonon dual thermal carriers, enhancing EM wave absorption and heat conduction. Benefiting from the boosted Ohmic loss, polarization loss, and multi-magnetic resonances, results showed that the CF@Co@C composites formed with a Co(NO₃)₂·6H₂O content of 0.005 mol exhibited a high EABW/d (3.55 GHz/mm) and strong absorption (−50.09 dB), excelling CFs and other absorbers. Meanwhile, the CF@Co@C/TPU composite films exhibited high heat conductivity (5.059–6.544 W/(m⋅K)) with a low load of 10 wt%. The highest heat conductivity was 1.85 and 1.43 times larger than those of pure TPU films and 2D CFs/TPU films. Furthermore, the theoretical analysis of the DOS and PDOS revealed the enhancement mechanisms of EM wave absorption and heat conduction. The multiple heterointerfaces between FCC-Co/C, HCP-Co/C, and FCC-Co/HCP-Co provided a built-in electric field for extra electric dipoles, thus enhancing the microwave absorption capabilities of materials. The combination of 2D CFs with Co@C foams enables cooperative heat transfer by electrons and multi-frequency phonons, thereby improving its heat conductivity. Overall, this work offers a novel and simple strategy to develop advanced dual-network composites with magnetic-dielectric dual losses and electron-phonon dual thermal carriers for EM protection and heat management applications in the electronics industry.

为了同时解决电子设备中电磁（EM）干扰和热量积累的关键问题，首先通过简单的浸渍退火工艺合成了具有双网络的组织纸衍生碳纤维（CF）@Co@C复合材料，作为一种先进的双功能填料。碳纤维与Co@C泡沫的掺入可以构建双网络、多异质界面、磁-介电双损耗和电子-声子双热载流子，增强电磁波吸收和热传导。结果表明，当Co(NO3)2·6H2O含量为0.005 mol时，得到的CF@Co@C复合材料具有较高的EABW/d （3.55 GHz/mm）和较强的吸收（- 50.09 dB），优于CFs等吸收材料。同时，CF@Co@C/TPU复合膜具有较高的导热系数（5.059 ~ 6.544 W/(m·K)），负载低至10 wt%。其最高导热系数分别是纯TPU膜和二维CFs/TPU膜的1.85倍和1.43倍。此外，理论分析还揭示了DOS和PDOS增强电磁波吸收和热传导的机理。FCC-Co/C、HCP-Co/C和FCC-Co/HCP-Co之间的多重异质界面为额外的电偶极子提供了内置电场，从而增强了材料的微波吸收能力。二维碳纤维与Co@C泡沫的结合使电子和多频声子的协同传热成为可能，从而提高了其导热性。总的来说，这项工作为开发先进的双网络复合材料提供了一种新颖而简单的策略，该复合材料具有磁-介电双损耗和电子-声子双热载流子，可用于电子工业中的电磁保护和热管理应用。

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引用次数: 0

Mechanistic insights into low-temperature oxidation of carbon fibers: Influence of hydrogen defects and crystallite size 碳纤维低温氧化的机理：氢缺陷和晶粒尺寸的影响

IF 11.6 2区材料科学 Q1 CHEMISTRY, PHYSICAL

Carbon

Pub Date : 2026-01-24 DOI: 10.1016/j.carbon.2026.121310

Z.E. Brubaker, D.H. Moseley, J. Neu, L. Kearney, A.J. Miskowiec, J.L. Niedziela

Although oxidation mechanisms have been exhaustively studied for graphite, similar analyses of carbon fibers are comparatively sparse. Most prior work has focused on quantifying weight loss or assessing protective surface coatings designed to slow oxidation. The use of optical spectroscopic techniques for oxidation analyses is comparatively unexplored, but such techniques could provide an early indicator of fiber oxidation that would undermine carbon fiber performance. In this work, we applied Raman spectroscopy to study oxidation-induced spectral alterations in 16 carbon fiber types from 7 manufacturers oxidized at 300 °C for 72 h, 400 °C for 8 h, and 500 °C for 1 h. We connect these results with structural properties of the carbon fibers obtained through wide-angle X-ray scattering, identifying a linear dependence between the reactivity of carbon fibers and the crystallite size of the unperturbed fibers. We then demonstrate that substituted hydrogen defects are likely removed from the fiber surface during oxidation and use the relative defect concentration to predict the Raman spectral change as a function of temperature and time, assuming Arrhenius behavior.¹

虽然对石墨的氧化机理已经进行了详尽的研究，但对碳纤维的类似分析相对较少。大多数先前的工作都集中在量化重量损失或评估设计用于减缓氧化的保护表面涂层。相对而言，利用光谱学技术进行氧化分析还未被探索，但这种技术可以提供纤维氧化的早期指标，从而破坏碳纤维的性能。在这项工作中，我们应用拉曼光谱研究了来自7家制造商的16种碳纤维在300°C氧化72小时、400°C氧化8小时和500°C氧化1小时的氧化引起的光谱变化。我们将这些结果与通过广角x射线散射获得的碳纤维结构特性联系起来，确定了碳纤维的反应性与未受扰动纤维的晶粒尺寸之间的线性依赖关系。然后，我们证明了在氧化过程中取代氢缺陷很可能从纤维表面去除，并使用相对缺陷浓度来预测拉曼光谱变化作为温度和时间的函数，假设阿伦尼乌斯行为

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引用次数: 0

Design and synthesis of core-shell Fe4N@C nanowires for efficient electromagnetic wave absorption and corrosion resistance 高效电磁波吸收和耐腐蚀的核壳纳米线Fe4N@C的设计与合成

IF 11.6 2区材料科学 Q1 CHEMISTRY, PHYSICAL

Carbon

Pub Date : 2026-01-23 DOI: 10.1016/j.carbon.2026.121306

Shuting Zhang , Chengguo Wang , Meijie Yu

To further enhance electromagnetic wave absorption capability and the marine corrosion resistance of ferromagnetic metallic materials, a dual-strategy approach combining the construction of the one-dimensional core-shell structure with Fe₄N phase transition was proposed. Through in-situ phenolic resin polymerization on Fe nanowire followed by carbonization-nitridation, core-shell Fe₄N@C nanowires were synthesized, where Fe₄N particles were successfully confined within high-aspect-ratio carbon shells. Distinctive structural and composition design optimized impedance matching and endowed the material with multiple loss mechanisms, including significant conductive loss, interfacial polarization, defect-induced dipole polarization and magnetic loss. Owing to a more balanced dielectric-magnetic synergistic loss relationship, the thicker-shell sample FWCN-2 achieved an impressive minimum reflection loss of −60.51 dB and a maximum effective absorption bandwidth of 7.28 GHz (2.65 mm, 10.72–18.00 GHz) at low filler loading, demonstrating outstanding electromagnetic wave absorption performance. Moreover, by Fe₄N phase transformation, FWCN-2 exhibited enhanced corrosion resistance in marine environments (E_corr = −0.13V, I_corr = 2.63 μA/cm²). This work offered a scalable and structure-guided route to lightweight, broadband, and corrosion-resistant electromagnetic wave absorbers.

为了进一步提高铁磁性金属材料的电磁波吸收能力和耐海洋腐蚀能力，提出了一种将一维核壳结构的构建与Fe4N相变相结合的双策略方法。通过酚醛树脂原位聚合Fe纳米线，然后碳化-氮化，合成了核壳Fe4N@C纳米线，其中Fe4N颗粒成功地限制在高纵横比的碳壳中。独特的结构和组成设计优化了阻抗匹配，并赋予材料多种损耗机制，包括显著的导电损耗、界面极化、缺陷诱导偶极子极化和磁损耗。由于更平衡的介质-磁协同损耗关系，厚壳样品fwn -2在低填料负载下的最小反射损耗为- 60.51 dB，最大有效吸收带宽为7.28 GHz (2.65 mm, 10.72-18.00 GHz)，表现出出色的电磁波吸收性能。通过Fe4N相变，FWCN-2在海洋环境中的耐蚀性增强（Ecorr = - 0.13V, Icorr = 2.63 μA/cm2）。这项工作为轻型、宽带和耐腐蚀电磁波吸收器提供了一种可扩展和结构导向的途径。

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引用次数: 0