Pub Date : 2024-11-14DOI: 10.1016/j.carbon.2024.119826
Ruyi Sha , Bingzhu Wang , Jixiang Dai , Jianjun Sha
Lightweight carbon aerogels are attractive for thermal insulation due to their low thermal conductivity and excellent high-temperature resistance under extreme environments. However, the preparation of monolithic carbon aerogels from phenolic resin precursor always faces the problem of large volumetric shrinkage during the drying and carbonization processes, thus resulting in the increasing density and thermal conductivity of aerogels. Here, to solve such issues, ultralight and rigid carbon foam was designed and synthesized as the reinforcement to fabricate carbon aerogel composites (CACs), which could significantly enhance the shrinkage resistance of monolithic carbon aerogels. The high rigidity of the carbon foam reinforcements (CFRs) was achieved through a pre-carbonization process, which also endowed the CFRs with a matched shrinkage with the monolithic carbon aerogels. As a result, the obtained CACs reinforced by the rigid CFRs showed not only crack-free structures, but also quite low shrinkage, which was about 5.9 % after carbonization. The low shrinkage of CACs then endowed them with quite low density (21.5 mg cm−3) and excellent thermal insulation performance (25.9 mW m−1 K−1). Furthermore, due to a highly rough nanostructure, the CACs also possessed outstanding hydrophobicity. These merits make the CACs a promising thermal insulation material even in humid environments.
{"title":"Novel ultralight carbon foam reinforced carbon aerogel composites with low volume shrinkage and excellent thermal insulation performance","authors":"Ruyi Sha , Bingzhu Wang , Jixiang Dai , Jianjun Sha","doi":"10.1016/j.carbon.2024.119826","DOIUrl":"10.1016/j.carbon.2024.119826","url":null,"abstract":"<div><div>Lightweight carbon aerogels are attractive for thermal insulation due to their low thermal conductivity and excellent high-temperature resistance under extreme environments. However, the preparation of monolithic carbon aerogels from phenolic resin precursor always faces the problem of large volumetric shrinkage during the drying and carbonization processes, thus resulting in the increasing density and thermal conductivity of aerogels. Here, to solve such issues, ultralight and rigid carbon foam was designed and synthesized as the reinforcement to fabricate carbon aerogel composites (CACs), which could significantly enhance the shrinkage resistance of monolithic carbon aerogels. The high rigidity of the carbon foam reinforcements (CFRs) was achieved through a pre-carbonization process, which also endowed the CFRs with a matched shrinkage with the monolithic carbon aerogels. As a result, the obtained CACs reinforced by the rigid CFRs showed not only crack-free structures, but also quite low shrinkage, which was about 5.9 % after carbonization. The low shrinkage of CACs then endowed them with quite low density (21.5 mg cm<sup>−3</sup>) and excellent thermal insulation performance (25.9 mW m<sup>−1</sup> K<sup>−1</sup>). Furthermore, due to a highly rough nanostructure, the CACs also possessed outstanding hydrophobicity. These merits make the CACs a promising thermal insulation material even in humid environments.</div></div>","PeriodicalId":262,"journal":{"name":"Carbon","volume":"232 ","pages":"Article 119826"},"PeriodicalIF":10.5,"publicationDate":"2024-11-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142656269","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-11-13DOI: 10.1016/j.carbon.2024.119825
Yongqi Zhao , Jingjing Wang , Danyi Yang , Zhao Du , Xinyu Zhi , Rongrong Yu , Zhonglu Guo , Chengchun Tang , Yi Fang
In view of the growing concern over electromagnetic wave pollution, the evolution of efficient microwave absorbing (MA) composites has emerged as a pivotal research area for scientists and engineers. In this study, MXene-CNTs/Co (MCC) composites with tunable and efficient MA properties were successfully prepared from a structural design perspective that capitalizes on dielectric-magnetic synergy. The electromagnetic properties of the composites were effectively regulated by adjusting the length and content of the CNTs. As expected, the design of the MCC composite absorber has a minimum reflection loss (RLmin) of −62.53 dB with a matched thickness of 1.59 mm. With an effective absorption bandwidth (EAB) of 4.20 GHz (12.48–16.68 GHz) and a matched thickness of 1.38 mm, the RLmin remains an impressive −41.29 dB. The exceptional MA characteristics are ascribed to its distinctive three-dimensional (3D) electromagnetic network configuration, which optimizes impedance matching and augments multi-component polarization loss and reflection/scattering capabilities. The findings of this study offer novel insights and methodologies for the advancement of efficient and tunable microwave absorbing materials.
{"title":"MXene-CNTs/Co dielectric-electromagnetic synergistic composites with multi-heterogeneous interfaces for microwave absorption","authors":"Yongqi Zhao , Jingjing Wang , Danyi Yang , Zhao Du , Xinyu Zhi , Rongrong Yu , Zhonglu Guo , Chengchun Tang , Yi Fang","doi":"10.1016/j.carbon.2024.119825","DOIUrl":"10.1016/j.carbon.2024.119825","url":null,"abstract":"<div><div>In view of the growing concern over electromagnetic wave pollution, the evolution of efficient microwave absorbing (MA) composites has emerged as a pivotal research area for scientists and engineers. In this study, MXene-CNTs/Co (MCC) composites with tunable and efficient MA properties were successfully prepared from a structural design perspective that capitalizes on dielectric-magnetic synergy. The electromagnetic properties of the composites were effectively regulated by adjusting the length and content of the CNTs. As expected, the design of the MCC composite absorber has a minimum reflection loss (RL<sub>min</sub>) of −62.53 dB with a matched thickness of 1.59 mm. With an effective absorption bandwidth (EAB) of 4.20 GHz (12.48–16.68 GHz) and a matched thickness of 1.38 mm, the RL<sub>min</sub> remains an impressive −41.29 dB. The exceptional MA characteristics are ascribed to its distinctive three-dimensional (3D) electromagnetic network configuration, which optimizes impedance matching and augments multi-component polarization loss and reflection/scattering capabilities. The findings of this study offer novel insights and methodologies for the advancement of efficient and tunable microwave absorbing materials.</div></div>","PeriodicalId":262,"journal":{"name":"Carbon","volume":"232 ","pages":"Article 119825"},"PeriodicalIF":10.5,"publicationDate":"2024-11-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142656267","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The urgent need for multifunctional, high-performance materials is critical in addressing environmental pollution and energy shortages faced by contemporary society. This research presents innovative NH2-MIL-88B/Ta4C3TX/graphene aerogels that exhibit exceptional capabilities in photocatalysis and thermal energy storage utilizing solar energy. Synthesized through a combination of hydrothermal and freeze-drying methods, these aerogels feature unique structural characteristics, including a hierarchical porous structure, low density, and a large specific surface area. Furthermore, the synergistic effects of NH2-MIL-88B, Ta4C3TX MXene, and the aerogel matrix contribute to remarkable physicochemical properties, such as high sunlight absorptivity and an optimal optical band gap that aligns well with the solar spectrum. These attributes enable the aerogels to photodegrade various dye and antibiotic drug solutions with high concentrations. The photodegradation efficiencies achieved were 75.57 % for Congo red, 61.56 % for methylene blue, and 58.57 % for tetracycline hydrochloride. Additionally, these aerogels exhibit significant adsorption capacities for various dyes and drugs. Moreover, when the phase change material polyethylene glycol is successfully integrated into the aerogels, they exhibit excellent thermal energy storage performance with leak-proof capabilities. A high photothermal conversion efficiency of 90.15 %, a phase enthalpy of 202.13 J g−1, and an enthalpy efficiency of 98.55 % provide evidence for this. This work provides valuable insights into the development of multifunctional aerogels aimed at addressing the challenges of wastewater treatment and energy shortages.
{"title":"Synergistic NH2-MIL-88B/Ta4C3TX/graphene aerogels for sustainable wastewater treatment and thermal energy storage","authors":"Jiarong Zhang , Long Yu , Ya'nan Zhao , Tianran Zhao , Yi'na Yang , Chunna Yu , Chang Zhao , Guangjian Xing","doi":"10.1016/j.carbon.2024.119823","DOIUrl":"10.1016/j.carbon.2024.119823","url":null,"abstract":"<div><div>The urgent need for multifunctional, high-performance materials is critical in addressing environmental pollution and energy shortages faced by contemporary society. This research presents innovative NH<sub>2</sub>-MIL-88B/Ta<sub>4</sub>C<sub>3</sub>T<sub>X</sub>/graphene aerogels that exhibit exceptional capabilities in photocatalysis and thermal energy storage utilizing solar energy. Synthesized through a combination of hydrothermal and freeze-drying methods, these aerogels feature unique structural characteristics, including a hierarchical porous structure, low density, and a large specific surface area. Furthermore, the synergistic effects of NH<sub>2</sub>-MIL-88B, Ta<sub>4</sub>C<sub>3</sub>T<sub>X</sub> MXene, and the aerogel matrix contribute to remarkable physicochemical properties, such as high sunlight absorptivity and an optimal optical band gap that aligns well with the solar spectrum. These attributes enable the aerogels to photodegrade various dye and antibiotic drug solutions with high concentrations. The photodegradation efficiencies achieved were 75.57 % for Congo red, 61.56 % for methylene blue, and 58.57 % for tetracycline hydrochloride. Additionally, these aerogels exhibit significant adsorption capacities for various dyes and drugs. Moreover, when the phase change material polyethylene glycol is successfully integrated into the aerogels, they exhibit excellent thermal energy storage performance with leak-proof capabilities. A high photothermal conversion efficiency of 90.15 %, a phase enthalpy of 202.13 J g<sup>−1</sup>, and an enthalpy efficiency of 98.55 % provide evidence for this. This work provides valuable insights into the development of multifunctional aerogels aimed at addressing the challenges of wastewater treatment and energy shortages.</div></div>","PeriodicalId":262,"journal":{"name":"Carbon","volume":"232 ","pages":"Article 119823"},"PeriodicalIF":10.5,"publicationDate":"2024-11-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142656266","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-11-12DOI: 10.1016/j.carbon.2024.119824
Nian Wang , Yikun Chen , Huichao Rao , Yujia Zou , Kai Nan , Yan Wang
In the domain of electromagnetic (EM) wave absorbing materials, the selection of suitable components and microstructures is an effective approach for designing the intense coupling of wave impedance and EM dissipation. In this study, we have successfully fabricated a double-carbon modified Co9S8/CoSe2 nanocube, where the core-shell Co9S8/CoSe2@C cube was anchored onto porous carbon (PC). The existence of three-dimensional (3D) porous carbon and the fabrication of Co9S8/CoSe2@C distributed on carbon nanosheets contribute to the improvement of conduction, magnetic losses, and the optimization of impedance matching. Substantial heterogeneous interfaces are generated between Co9S8, CoSe2, carbon shells, and PC, leading to extensive interfacial polarization and facilitating the transformation of EM energy into thermal energy. The abundant defects, S and Se vacancies in carbon component can act as polarization centers, inducing dipolar polarization and thus increasing the electromagnetic wave (EMW) loss. The Co9S8/CoSe2@C@PC exhibits the best microwave absorption properties, with a minimum reflection loss (RLmin) of −64.1 dB at 2.5 mm and an effective absorption bandwidth (EAB) of 6.3 GHz. The High-Frequency Structure Simulator results indicate the RCS values of the samples within the range of −90 °C < θ < 90 °C are lower than −20 dB m2, which can achieve almost full-angle coverage in the actual environment. This research offers inspiration and strategies for the design and synthesis of multi-component magneto-electric composites based on transitional metal chalcogenides.
在电磁波吸收材料领域，选择合适的成分和微结构是设计波阻抗和电磁耗散强耦合的有效方法。在这项研究中，我们成功制备了一种双碳改性 Co9S8/CoSe2 纳米立方体，将核壳 Co9S8/CoSe2@C 立方体锚定在多孔碳（PC）上。三维（3D）多孔碳的存在和分布在碳纳米片上的 Co9S8/CoSe2@C 的制造有助于改善传导、磁损耗和阻抗匹配的优化。Co9S8、CoSe2、碳壳和 PC 之间产生了大量的异质界面，导致了广泛的界面极化，促进了电磁能向热能的转化。碳成分中丰富的缺陷、S 和 Se 空位可充当极化中心，诱发双极化，从而增加电磁波（EMW）损耗。Co9S8/CoSe2@C@PC 具有最佳的微波吸收特性，在 2.5 毫米处的最小反射损耗（RLmin）为 -64.1 dB，有效吸收带宽（EAB）为 6.3 GHz。高频结构模拟器结果表明，样品在 -90 °C < θ < 90 °C 范围内的 RCS 值低于 -20 dB m2，在实际环境中几乎可以实现全角度覆盖。这项研究为设计和合成基于过渡金属瑀的多组分磁电复合材料提供了灵感和策略。
{"title":"Hierarchical core-shell transitional metal chalcogenides Co9S8/ CoSe2@C nanocube embedded into porous carbon for tunable and efficient microwave absorption","authors":"Nian Wang , Yikun Chen , Huichao Rao , Yujia Zou , Kai Nan , Yan Wang","doi":"10.1016/j.carbon.2024.119824","DOIUrl":"10.1016/j.carbon.2024.119824","url":null,"abstract":"<div><div>In the domain of electromagnetic (EM) wave absorbing materials, the selection of suitable components and microstructures is an effective approach for designing the intense coupling of wave impedance and EM dissipation. In this study, we have successfully fabricated a double-carbon modified Co<sub>9</sub>S<sub>8</sub>/CoSe<sub>2</sub> nanocube, where the core-shell Co<sub>9</sub>S<sub>8</sub>/CoSe<sub>2</sub>@C cube was anchored onto porous carbon (PC). The existence of three-dimensional (3D) porous carbon and the fabrication of Co<sub>9</sub>S<sub>8</sub>/CoSe<sub>2</sub>@C distributed on carbon nanosheets contribute to the improvement of conduction, magnetic losses, and the optimization of impedance matching. Substantial heterogeneous interfaces are generated between Co<sub>9</sub>S<sub>8</sub>, CoSe<sub>2</sub>, carbon shells, and PC, leading to extensive interfacial polarization and facilitating the transformation of EM energy into thermal energy. The abundant defects, S and Se vacancies in carbon component can act as polarization centers, inducing dipolar polarization and thus increasing the electromagnetic wave (EMW) loss. The Co<sub>9</sub>S<sub>8</sub>/CoSe<sub>2</sub>@C@PC exhibits the best microwave absorption properties, with a minimum reflection loss (RL<sub>min</sub>) of −64.1 dB at 2.5 mm and an effective absorption bandwidth (EAB) of 6.3 GHz. The High-Frequency Structure Simulator results indicate the RCS values of the samples within the range of −90 °C < θ < 90 °C are lower than −20 dB m<sup>2</sup>, which can achieve almost full-angle coverage in the actual environment. This research offers inspiration and strategies for the design and synthesis of multi-component magneto-electric composites based on transitional metal chalcogenides.</div></div>","PeriodicalId":262,"journal":{"name":"Carbon","volume":"232 ","pages":"Article 119824"},"PeriodicalIF":10.5,"publicationDate":"2024-11-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142655844","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-11-10DOI: 10.1016/j.carbon.2024.119814
Peng-an Zong , Mengran Chen , Xia Wang , Heng Liu , Zhengxi He , Yixiang Ou , Chuan Sun
Functional films with electromagnetic interference (EMI) shielding capabilities and pressure sensing functions epitomize the intersection of materials science and electronics. These films not only protect against electromagnetic interference but also provide essential data on mechanical stresses, thus improving the reliability, performance, and safety of electronic devices and structures. Carbon cloth (CC) offer excellent air and moisture permeability, ensuring long-term comfort when in contact with human skin; however, they face challenges in achieving highly effective EMI shielding. In this study, a Cu3Se2 coated CC based composite film was fabricated using a facile electrodeposition method. The EMI shielding effectiveness was significantly enhanced from 15 dB to 63 dB, a more than fourfold improvement. The Cu3Se2/CC film also demonstrated distinctive resistance variation and high sensitivity when used as pressure sensors to detect human motions, including finger bending, wrist flexion, knee movement, and elbow swing. Additionally, the Cu3Se2-modified textile exhibited flame retardancy, excellent flexibility, and breathability. This work highlights the potential for cost-effective, high-EMI-shielding textile sensors and paves the way for the development of multifunctional wearable electronics.
具有电磁干扰（EMI）屏蔽能力和压力传感功能的功能薄膜是材料科学与电子学交叉学科的缩影。这些薄膜不仅能防止电磁干扰，还能提供有关机械应力的重要数据，从而提高电子设备和结构的可靠性、性能和安全性。碳布（CC）具有优异的透气性和透湿性，可确保与人体皮肤接触时的长期舒适性；然而，它们在实现高效电磁干扰屏蔽方面面临挑战。在本研究中，采用简便的电沉积方法制备了基于 CC 的 Cu3Se2 涂层复合薄膜。EMI 屏蔽效果从 15 dB 显著提高到 63 dB，提高了四倍多。Cu3Se2/CC 薄膜在用作压力传感器检测人体运动（包括手指弯曲、手腕弯曲、膝关节运动和肘关节摆动）时，也表现出独特的电阻变化和高灵敏度。此外，Cu3Se2 改性纺织品还具有阻燃性、出色的柔韧性和透气性。这项工作凸显了具有成本效益的高 EMI 屏蔽纺织品传感器的潜力，并为多功能可穿戴电子产品的开发铺平了道路。
{"title":"Coating carbon cloth with Cu3Se2 by electrodeposition for pressure sensing and enhanced EMI shielding","authors":"Peng-an Zong , Mengran Chen , Xia Wang , Heng Liu , Zhengxi He , Yixiang Ou , Chuan Sun","doi":"10.1016/j.carbon.2024.119814","DOIUrl":"10.1016/j.carbon.2024.119814","url":null,"abstract":"<div><div>Functional films with electromagnetic interference (EMI) shielding capabilities and pressure sensing functions epitomize the intersection of materials science and electronics. These films not only protect against electromagnetic interference but also provide essential data on mechanical stresses, thus improving the reliability, performance, and safety of electronic devices and structures. Carbon cloth (CC) offer excellent air and moisture permeability, ensuring long-term comfort when in contact with human skin; however, they face challenges in achieving highly effective EMI shielding. In this study, a Cu<sub>3</sub>Se<sub>2</sub> coated CC based composite film was fabricated using a facile electrodeposition method. The EMI shielding effectiveness was significantly enhanced from 15 dB to 63 dB, a more than fourfold improvement. The Cu<sub>3</sub>Se<sub>2</sub>/CC film also demonstrated distinctive resistance variation and high sensitivity when used as pressure sensors to detect human motions, including finger bending, wrist flexion, knee movement, and elbow swing. Additionally, the Cu<sub>3</sub>Se<sub>2</sub>-modified textile exhibited flame retardancy, excellent flexibility, and breathability. This work highlights the potential for cost-effective, high-EMI-shielding textile sensors and paves the way for the development of multifunctional wearable electronics.</div></div>","PeriodicalId":262,"journal":{"name":"Carbon","volume":"232 ","pages":"Article 119814"},"PeriodicalIF":10.5,"publicationDate":"2024-11-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142656207","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-11-09DOI: 10.1016/j.carbon.2024.119788
Le Huang , Caiting Li , Xuan Liu , Shanhong Li , Lei Gao , Xueyu Du , Youcai Zhu , Jungang Zhao , Kuang Yang , Ziang Zhang , Ying Zhang
In this work, toluene removal by activated coke (ACK) was investigated. For the first time, metal-free carbon catalytic oxidation of toluene on ACK was experimentally demonstrated. On this basis, the active sources of carbon catalytic oxidation of toluene on ACK, including surface defects, pore grading degree (V/V), and surface oxygen functional groups, were identified in combination with characterization tests. The catalytic effects of different oxygen-containing functional groups (C=O, COO-, C-O-) on toluene oxidation were analyzed. The carbon catalytic oxidation reaction path of toluene on ACK has been determined as follows: toluene benzyl alcohol benzaldehyde benzoic acid maleic anhydride carbon dioxide and water. It can be divided into three steps: initial oxidation of toluene to benzyl alcohol and benzaldehyde on C=O; deep non-mineralized oxidation of benzyl alcohol and benzaldehyde on C=O, COO-, C-O-; and mineralized oxidation of intermediate products on C-O- to produce CO. The gradual oxidation of toluene promotes the interconversion of C=O, COO-, and C-O-, with the assistance of O and reactive oxygen species (O) generated by activation of O and adsorbed water.
{"title":"Metal-free carbon catalysis of toluene on activated coke and its active sources","authors":"Le Huang , Caiting Li , Xuan Liu , Shanhong Li , Lei Gao , Xueyu Du , Youcai Zhu , Jungang Zhao , Kuang Yang , Ziang Zhang , Ying Zhang","doi":"10.1016/j.carbon.2024.119788","DOIUrl":"10.1016/j.carbon.2024.119788","url":null,"abstract":"<div><div>In this work, toluene removal by activated coke (ACK) was investigated. For the first time, metal-free carbon catalytic oxidation of toluene on ACK was experimentally demonstrated. On this basis, the active sources of carbon catalytic oxidation of toluene on ACK, including surface defects, pore grading degree (V<span><math><msub><mrow></mrow><mrow><mi>m</mi><mi>e</mi><mi>s</mi><mo>+</mo><mi>m</mi><mi>a</mi><mi>c</mi></mrow></msub></math></span>/V<span><math><msub><mrow></mrow><mrow><mi>t</mi></mrow></msub></math></span>), and surface oxygen functional groups, were identified in combination with characterization tests. The catalytic effects of different oxygen-containing functional groups (C=O, COO-, C-O-) on toluene oxidation were analyzed. The carbon catalytic oxidation reaction path of toluene on ACK has been determined as follows: toluene <span><math><mo>→</mo></math></span> benzyl alcohol <span><math><mo>→</mo></math></span> benzaldehyde <span><math><mo>→</mo></math></span> benzoic acid <span><math><mo>→</mo></math></span> maleic anhydride <span><math><mo>→</mo></math></span> carbon dioxide and water. It can be divided into three steps: initial oxidation of toluene to benzyl alcohol and benzaldehyde on C=O; deep non-mineralized oxidation of benzyl alcohol and benzaldehyde on C=O, COO-, C-O-; and mineralized oxidation of intermediate products on C-O- to produce CO<span><math><msub><mrow></mrow><mrow><mn>2</mn></mrow></msub></math></span>. The gradual oxidation of toluene promotes the interconversion of C=O, COO-, and C-O-, with the assistance of O<span><math><msub><mrow></mrow><mrow><mn>2</mn></mrow></msub></math></span> and reactive oxygen species (O<span><math><msup><mrow></mrow><mrow><mo>∗</mo></mrow></msup></math></span>) generated by activation of O<span><math><msub><mrow></mrow><mrow><mn>2</mn></mrow></msub></math></span> and adsorbed water.</div></div>","PeriodicalId":262,"journal":{"name":"Carbon","volume":"232 ","pages":"Article 119788"},"PeriodicalIF":10.5,"publicationDate":"2024-11-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142656270","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-11-09DOI: 10.1016/j.carbon.2024.119815
Tao Wang , Ruizheng Zhong , Yimeng Fu , Chidan Wan , Xin Zhou , Zhiyong He , Mei Liu , Can Wu , Yong Tang
The design and construction of novel micro-droplet electrochemical sensor is crucial for the development of electrochemical analysis. The core of micro-droplet electrochemical sensors lies in fabricating effective electrode substrate materials and surface-active materials. MXene have been widely used for electrochemical sensors due to its high conductivity and excellent hydrophilicity. However, MXene-based materials are rarely used for the fabrication of micro-droplet electrochemical sensors. Besides, pure MXene materials often fall short of meeting trace detection requirements for specific substances, which necessitates the surface modification of these MXene materials. This work aims at fabricating novel MXene-based micro-droplet electrochemical sensor for veterinary drug residues detection. In order to achieve this purpose, cationic surfactant cetyltrimethylammonium bromide (CTAB) was intercalated into the interlayers of Ti3C2Tx nanosheets, enlarging its interlayer spacing. Meanwhile, CTAB molecules were also bonded on the surface of Ti3C2Tx nanosheets through electrostatic adsorption, inducing the assembly of small-sized Ti3C2Tx nanosheets into larger ones (CTAB@Ti3C2Tx) and endowing Ti3C2Tx nanosheets with positively charged surface. Compared with pristine Ti3C2Tx nanosheets, the hydrophilicity and adsorption capacity of CTAB@Ti3C2Tx were effectively boosted. After then, CTAB@Ti3C2Tx were modified on the surface of integrated laser-induced graphene (LIG) electrodes. As a result, CTAB@Ti3C2Tx/LIG showed enhanced electrochemical activity and rapid, sensitive micro-droplet electrochemical detection for paracetamol and fenbendazole veterinary drug residues were achieved. Finally, the constructed CTAB@Ti3C2Tx/LIG micro-droplet electrochemical sensor was employed for the detection of paracetamol and fenbendazole in pork and milk samples, exhibiting satisfactory detection accuracy.
{"title":"CTAB@Ti3C2Tx/laser-induced graphene for the detection of veterinary drugs in micro-droplet","authors":"Tao Wang , Ruizheng Zhong , Yimeng Fu , Chidan Wan , Xin Zhou , Zhiyong He , Mei Liu , Can Wu , Yong Tang","doi":"10.1016/j.carbon.2024.119815","DOIUrl":"10.1016/j.carbon.2024.119815","url":null,"abstract":"<div><div>The design and construction of novel micro-droplet electrochemical sensor is crucial for the development of electrochemical analysis. The core of micro-droplet electrochemical sensors lies in fabricating effective electrode substrate materials and surface-active materials. MXene have been widely used for electrochemical sensors due to its high conductivity and excellent hydrophilicity. However, MXene-based materials are rarely used for the fabrication of micro-droplet electrochemical sensors. Besides, pure MXene materials often fall short of meeting trace detection requirements for specific substances, which necessitates the surface modification of these MXene materials. This work aims at fabricating novel MXene-based micro-droplet electrochemical sensor for veterinary drug residues detection. In order to achieve this purpose, cationic surfactant cetyltrimethylammonium bromide (CTAB) was intercalated into the interlayers of Ti<sub>3</sub>C<sub>2</sub>T<sub>x</sub> nanosheets, enlarging its interlayer spacing. Meanwhile, CTAB molecules were also bonded on the surface of Ti<sub>3</sub>C<sub>2</sub>T<sub>x</sub> nanosheets through electrostatic adsorption, inducing the assembly of small-sized Ti<sub>3</sub>C<sub>2</sub>T<sub>x</sub> nanosheets into larger ones (CTAB@Ti<sub>3</sub>C<sub>2</sub>T<sub>x</sub>) and endowing Ti<sub>3</sub>C<sub>2</sub>T<sub>x</sub> nanosheets with positively charged surface. Compared with pristine Ti<sub>3</sub>C<sub>2</sub>T<sub>x</sub> nanosheets, the hydrophilicity and adsorption capacity of CTAB@Ti<sub>3</sub>C<sub>2</sub>T<sub>x</sub> were effectively boosted. After then, CTAB@Ti<sub>3</sub>C<sub>2</sub>T<sub>x</sub> were modified on the surface of integrated laser-induced graphene (LIG) electrodes. As a result, CTAB@Ti<sub>3</sub>C<sub>2</sub>T<sub>x</sub>/LIG showed enhanced electrochemical activity and rapid, sensitive micro-droplet electrochemical detection for paracetamol and fenbendazole veterinary drug residues were achieved. Finally, the constructed CTAB@Ti<sub>3</sub>C<sub>2</sub>T<sub>x</sub>/LIG micro-droplet electrochemical sensor was employed for the detection of paracetamol and fenbendazole in pork and milk samples, exhibiting satisfactory detection accuracy.</div></div>","PeriodicalId":262,"journal":{"name":"Carbon","volume":"232 ","pages":"Article 119815"},"PeriodicalIF":10.5,"publicationDate":"2024-11-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142656204","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-11-09DOI: 10.1016/j.carbon.2024.119812
Lingzhi Cheng , Kang Cheng , Shuxuan Qu , Xinrong Jiang , Xin Sui , Munan Lu , Weibang Lyu
Floating catalyst chemical vapor deposition (FCCVD) is a key method for synthesizing high-strength, electrically conductive carbon nanotube (CNT) fibers. However, the high porosity of FCCVD CNT fibers limits the full utilization of the intrinsic performance of CNTs. It remains a challenge to assemble and continuous fabricate high-performance CNT fibers. Herein, this study proposed an impregnation-wet twisting-pyrolysis process to fabricate continuous CNT/SiC composite fibers to enhance the mechanical and electrical properties by reducing pore sizes and improving the interaction between CNTs. The resulting compact structure and enhanced interfacial interactions of the CNT/SiC fibers exhibited both high strength (2015.27 MPa) and high electrical conductivity (7.2 × 105 S/m), representing increases of 130.8 % and 69.9 % compared to pristine CNT fibers. The unidirectional laminates assembled by continuous CNT/SiC fibers demonstrated high electromagnetic interference (EMI) shielding effectiveness of 66.33 dB. This innovative continuous process holds significant potential for the industrial utilization of CNT/SiC fibers.
{"title":"Innovative fabrication of CNT/SiC composite fibers via impregnation-wet twisting-pyrolysis: Advancements in strength, conductivity, and EMI shielding","authors":"Lingzhi Cheng , Kang Cheng , Shuxuan Qu , Xinrong Jiang , Xin Sui , Munan Lu , Weibang Lyu","doi":"10.1016/j.carbon.2024.119812","DOIUrl":"10.1016/j.carbon.2024.119812","url":null,"abstract":"<div><div>Floating catalyst chemical vapor deposition (FCCVD) is a key method for synthesizing high-strength, electrically conductive carbon nanotube (CNT) fibers. However, the high porosity of FCCVD CNT fibers limits the full utilization of the intrinsic performance of CNTs. It remains a challenge to assemble and continuous fabricate high-performance CNT fibers. Herein, this study proposed an impregnation-wet twisting-pyrolysis process to fabricate continuous CNT/SiC composite fibers to enhance the mechanical and electrical properties by reducing pore sizes and improving the interaction between CNTs. The resulting compact structure and enhanced interfacial interactions of the CNT/SiC fibers exhibited both high strength (2015.27 MPa) and high electrical conductivity (7.2 × 10<sup>5</sup> S/m), representing increases of 130.8 % and 69.9 % compared to pristine CNT fibers. The unidirectional laminates assembled by continuous CNT/SiC fibers demonstrated high electromagnetic interference (EMI) shielding effectiveness of 66.33 dB. This innovative continuous process holds significant potential for the industrial utilization of CNT/SiC fibers.</div></div>","PeriodicalId":262,"journal":{"name":"Carbon","volume":"232 ","pages":"Article 119812"},"PeriodicalIF":10.5,"publicationDate":"2024-11-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142656205","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-11-09DOI: 10.1016/j.carbon.2024.119816
Niladri Talukder , Yudong Wang , Xiao Tong , Eon Soo Lee
Integrating N-doped graphene (N-G) with Metal-Organic Frameworks (MOFs) enhances catalytic activity for oxygen reduction reaction (ORR), often exceeding both the performances of their precursors and, in some cases, even Platinum group metal (PGM)-based catalysts. However, the factors driving this improved catalytic activity in N-G/MOF composites remain unexplored, particularly from the perspective of the chemical changes. To investigate the chemical changes in N-G and MOF upon their integration and the implications of these changes on ORR catalytic activity, an N-G/MOF was synthesized from N-G with a MOF (ZIF-8) following a mechanochemical wet ball milling process. The N-G, ZIF-8, and N-G/MOF samples were examined for changes in elemental composition, chemical state of carbon, different nitrogen and carbon bonds, and other chemical interactions. In the N-G/MOF catalyst, compared to its N-G and ZIF-8 precursors, the relative oxygen content increased, indicating the formation of additional oxygen-containing groups. The C 1s peak shifted to a lower binding energy in N-G/MOF, suggesting changes in the overall chemical or oxidation state of the carbon atoms. Besides, the increase in pyridinic-N functional groups in N-G/MOF points to the formation of additional active sites. Furthermore, the formation of C–Zn bonds in N-G/MOF suggests the probable emergence of single-atom Zn sites, while the increase in CO bonds points to the formation of carboxyl or carbonyl groups. These chemical changes could be linked to the enhanced electrocatalytic activity of the N-G/MOF composite for ORR. This study may also be beneficial for other research focused on developing composite catalysts involving various N-G and MOFs-based materials.
{"title":"Chemical changes from N-doped graphene and Metal-Organic Frameworks to N-G/MOF composites for improved electrocatalytic activity","authors":"Niladri Talukder , Yudong Wang , Xiao Tong , Eon Soo Lee","doi":"10.1016/j.carbon.2024.119816","DOIUrl":"10.1016/j.carbon.2024.119816","url":null,"abstract":"<div><div>Integrating N-doped graphene (N-G) with Metal-Organic Frameworks (MOFs) enhances catalytic activity for oxygen reduction reaction (ORR), often exceeding both the performances of their precursors and, in some cases, even Platinum group metal (PGM)-based catalysts. However, the factors driving this improved catalytic activity in N-G/MOF composites remain unexplored, particularly from the perspective of the chemical changes. To investigate the chemical changes in N-G and MOF upon their integration and the implications of these changes on ORR catalytic activity, an N-G/MOF was synthesized from N-G with a MOF (ZIF-8) following a mechanochemical wet ball milling process. The N-G, ZIF-8, and N-G/MOF samples were examined for changes in elemental composition, chemical state of carbon, different nitrogen and carbon bonds, and other chemical interactions. In the N-G/MOF catalyst, compared to its N-G and ZIF-8 precursors, the relative oxygen content increased, indicating the formation of additional oxygen-containing groups. The C 1s peak shifted to a lower binding energy in N-G/MOF, suggesting changes in the overall chemical or oxidation state of the carbon atoms. Besides, the increase in pyridinic-N functional groups in N-G/MOF points to the formation of additional active sites. Furthermore, the formation of C–Zn bonds in N-G/MOF suggests the probable emergence of single-atom Zn sites, while the increase in C<img>O bonds points to the formation of carboxyl or carbonyl groups. These chemical changes could be linked to the enhanced electrocatalytic activity of the N-G/MOF composite for ORR. This study may also be beneficial for other research focused on developing composite catalysts involving various N-G and MOFs-based materials.</div></div>","PeriodicalId":262,"journal":{"name":"Carbon","volume":"232 ","pages":"Article 119816"},"PeriodicalIF":10.5,"publicationDate":"2024-11-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142656262","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-11-09DOI: 10.1016/j.carbon.2024.119817
Luyao Han, Haibo Yang, Zhixin Cai, Ying Lin
Although carbon fibers have significant dielectric loss, poor impedance matching often results in a narrow effective absorption bandwidth, which in turn induces unsatisfactory microwave absorption (MA). The composition and microstructure are remarkably critical factors in order to optimize the MA performance. Herein, the flexible magnetic carbon nanofibers (CoFe@CNFs) were prepared based on one-dimensional carbon nanofibers and core-shell MOF derivatives by electrospinning technology and subsequent high-temperature heat treatment. The integration of core-shell ZIF-67@ CoFe-PBA derivatives, the three-dimensionalconductive network of carbon nanofibers and the synergistic magnetic loss and dielectric loss significantly optimizes the impedance matching, which enables the CoFe@CNFs to simultaneously achieve favorable MA performance and lightweight characteristics. The CoFe@CNFs show a minimum reflection loss value of −47.9 dB and the maximum effective absorption bandwidth of 6.5 GHz when the filling ratio is only 7.5 wt%. In addition, the complex composition and unique microstructure endow the composites with excellent flexibility. This work provides a meaningful guidance for constructing lightweight MA materials with broadband absorption characteristics.
尽管碳纤维具有显著的介电损耗，但阻抗匹配不良往往会导致有效吸收带宽变窄，进而导致微波吸收（MA）效果不理想。要优化微波吸收性能，成分和微结构是至关重要的因素。本文基于一维碳纳米纤维和核壳MOF衍生物，采用电纺丝技术制备了柔性磁性碳纳米纤维（CoFe@CNFs），并对其进行了高温热处理。核壳 ZIF-67@ CoFe-PBA 衍生物、碳纳米纤维的三维导电网络以及磁损和介损的协同作用显著优化了阻抗匹配，使 CoFe@CNFs 同时具有良好的 MA 性能和轻质特性。当填充率仅为 7.5 wt% 时，CoFe@CNFs 的最小反射损耗值为 -47.9 dB，最大有效吸收带宽为 6.5 GHz。此外，复杂的成分和独特的微观结构还赋予了复合材料极佳的柔韧性。这项研究为构建具有宽带吸收特性的轻质 MA 材料提供了有意义的指导。
{"title":"Construction of flexible magnetic carbon nanofibers by core-shell MOF derivatives for optimizing microwave absorption","authors":"Luyao Han, Haibo Yang, Zhixin Cai, Ying Lin","doi":"10.1016/j.carbon.2024.119817","DOIUrl":"10.1016/j.carbon.2024.119817","url":null,"abstract":"<div><div>Although carbon fibers have significant dielectric loss, poor impedance matching often results in a narrow effective absorption bandwidth, which in turn induces unsatisfactory microwave absorption (MA). The composition and microstructure are remarkably critical factors in order to optimize the MA performance. Herein, the flexible magnetic carbon nanofibers (CoFe@CNFs) were prepared based on one-dimensional carbon nanofibers and core-shell MOF derivatives by electrospinning technology and subsequent high-temperature heat treatment. The integration of core-shell ZIF-67@ CoFe-PBA derivatives, the three-dimensionalconductive network of carbon nanofibers and the synergistic magnetic loss and dielectric loss significantly optimizes the impedance matching, which enables the CoFe@CNFs to simultaneously achieve favorable MA performance and lightweight characteristics. The CoFe@CNFs show a minimum reflection loss value of −47.9 dB and the maximum effective absorption bandwidth of 6.5 GHz when the filling ratio is only 7.5 wt%. In addition, the complex composition and unique microstructure endow the composites with excellent flexibility. This work provides a meaningful guidance for constructing lightweight MA materials with broadband absorption characteristics.</div></div>","PeriodicalId":262,"journal":{"name":"Carbon","volume":"232 ","pages":"Article 119817"},"PeriodicalIF":10.5,"publicationDate":"2024-11-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142656209","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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