Carbon Trends最新文献_第5页

Mechanical parameters of chitosan film with glycerol and propylene carbonate 甘油和碳酸丙烯酯制备壳聚糖膜的力学参数

IF 3.9 Q2 MATERIALS SCIENCE, MULTIDISCIPLINARY

Carbon Trends

Pub Date : 2025-09-26 DOI: 10.1016/j.cartre.2025.100563

Paula Ponce , Edward Ávila , Zaillmar Morales , Carlos Reinoso , Antonio Díaz , Carlos Loyo , Juan Pablo Saucedo-Vázquez , Thibault Terencio , José Mora , Floralba López

Chitosan films were prepared by incorporating glycerol (GLY) and propylene carbonate (PC) to enhance their mechanical performance for applications in which material conformability is prioritized over mechanical strength. The addition of GLY significantly increased the flexibility of films, with the elongation at break reaching values approximately four times higher than those of unplasticized chitosan. Although PC is not an effective plasticizer as GLY when used alone, its combination with GLY produced a synergistic effect that further enhanced film flexibility, achieving elongation values up to six times greater than the unmodified chitosan. This improvement was accompanied by a marked decrease in tensile strength and elastic modulus, not only due to the individual plasticizing effects of GLY and PC, but also as a result of their combined interaction, which disrupts interchain hydrogen bonding and increases polymer chain mobility. The optimal mechanical profile was observed at a composition of 30% GLY and 15% PC, yielding an elongation at break about 66%, an elastic modulus of 24 MPa, and a tensile strength of 17 MPa. In addition, thermal analysis revealed improved thermal stability, attributed to structural changes induced by the incorporation of both plasticizers. Overall, the results highlight the potential of using a GLY–PC blend to fine-tune the mechanical and thermal properties of chitosan films, making them promising candidates for sustainable and conformable environmentally friendly materials.

通过添加甘油（GLY）和碳酸丙烯酯（PC）制备壳聚糖薄膜，以提高其机械性能，以满足材料相容性优先于机械强度的应用。GLY的加入显著提高了薄膜的柔韧性，断裂伸长率达到未增塑壳聚糖的四倍左右。虽然单独使用时，PC不是像GLY那样有效的增塑剂，但它与GLY的结合产生了协同效应，进一步增强了薄膜的柔韧性，达到了比未改性的壳聚糖高6倍的伸长率。这种改善伴随着拉伸强度和弹性模量的显著下降，这不仅是由于GLY和PC的单独塑化作用，也是由于它们的联合相互作用，破坏了链间氢键并增加了聚合物链的迁移率。当GLY和PC的含量分别为30%和15%时，其断裂伸长率约为66%，弹性模量为24 MPa，抗拉强度为17 MPa。此外，热分析显示，由于两种增塑剂的掺入引起的结构变化，热稳定性得到了改善。总的来说，研究结果强调了使用GLY-PC共混物来微调壳聚糖薄膜的机械和热性能的潜力，使它们成为可持续和环保材料的有希望的候选者。

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引用次数: 0

Reliable prediction of the band gap properties of graphene buffer layer on SiC using meta-GGA approximation 基于meta-GGA近似的碳化硅上石墨烯缓冲层带隙特性可靠预测

IF 3.9 Q2 MATERIALS SCIENCE, MULTIDISCIPLINARY

Carbon Trends

Pub Date : 2025-09-24 DOI: 10.1016/j.cartre.2025.100575

Elaheh Mohebbi , Eleonora Pavoni , Pierluigi Stipa , Marina Petroselli , Luca Pierantoni , Emiliano Laudadio , Davide Mencarelli

While different Density Functional Theory (DFT) methods have been performed to determine the electronic band structure of graphene buffer layer (GBL) over the Si-terminated SiC (0001) surface, still a correct band gap (E_gap) close to the experimental one has never been demonstrated. The novelty of this study is that for the first time the outcomes have reproduced the experimental E_gap (greater than 0.5 eV) of GBL@SiC (0001) system with an indirect/direct E_gap of 0.65/0.80 eV using improved Meta Generalized Gradient Approximation (MGGA) methodology with medium basis set (MGGA-Medium). The results revealed that GBL has lower E_gap with other basis sets of MGGA-High with 0.32 eV (indirect) and 0.33 eV (direct), whereas MGGA-Ultra estimated a zero E_gap. Absorption spectrum indicated that the presence of two peaks at 61,801 cm^-1 and 64,833 cm^-1 at 265 THz and 290 THz for GBL/SiC along the xx- and yy- (in-plane) directions, respectively. The Im(ω) reveal that the optical E_gap is around 181 THz. Furthermore, Re(ω) of GBL monolayer after the interface on SiC (0001) has predicted to be 2.34, 2.32 and 1.07 along with the xx-, yy- in-plane and zz- out-of-plane polarizations, respectively. More information about the optical properties of this interface show that maximum static value of

n

along the xx- in-plane direction calculated to be 1.58, while initial non-zero value of

κ

is about 12.08 THz.

虽然已经使用了不同的密度泛函理论（DFT）方法来确定si端SiC（0001）表面上石墨烯缓冲层（GBL）的电子能带结构，但仍然没有证明接近实验带隙的正确带隙（Egap）。本研究的新颖之处在于，首次使用改进的中等基集（MGGA- medium）的Meta广义梯度近似（MGGA）方法再现了GBL@SiC（0001）系统的实验Egap（大于0.5 eV），间接/直接Egap为0.65/0.80 eV。结果表明，GBL与其他MGGA-High基组的Egap值较低，分别为0.32 eV（间接）和0.33 eV（直接），而MGGA-Ultra基组的Egap值为零。吸收光谱表明，GBL/SiC在xx-和yy-（面内）方向分别在265 THz和290 THz处存在61801 cm-1和64833 cm-1两个峰。Im（ω）显示光学Egap约为181太赫兹。此外，在SiC（0001）界面后的GBL单层的Re（ω）分别为2.34,2.32和1.07，分别为xx-， yy-面内和zz-面外极化。关于该接口光学特性的更多信息表明，沿xx-面内方向n的最大静态值计算为1.58，而κ的初始非零值约为12.08 THz。

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引用次数: 0

Palladium supported over carbon nanotubes catalytic system for green diesel production 碳纳米管催化系统支持钯的绿色柴油生产

IF 3.9 Q2 MATERIALS SCIENCE, MULTIDISCIPLINARY

Carbon Trends

Pub Date : 2025-09-24 DOI: 10.1016/j.cartre.2025.100576

Stefano Savino , Elena Ghedini , Andrea L. Aloia , Antonio Monopoli , Francesco Taddeo , Tommaso Castiglia , Angelo Nacci , Stanislav Yakushkin , Blaž Likozar , Michele Casiello , Lucia D'Accolti

Addressing the urgent need for sustainable biofuels, for the first time in the literature a palladium catalyst supported on multi-walled carbon nanotubes (Pd@MWCNTs) was used for promoting deoxygenation (DO) of fatty acids and triglycerides to produce green diesel. Reaction was conducted in water as a green solvent under relatively mild conditions (250°C, 16 bar H₂). The catalyst was prepared modifying known procedures, using oxidative pretreatment of nanotubes, and characterized by FTIR, SEM-EDX, BET, NH₃-TPD, XPS, physi- and chemisorption techniques. Catalytic performances of Pd@MWCNTs were compared with those of commercial Pd/C and different reactivity was explained on the base of chemical and morphologic features. Pd@MWCNTs gave a complete conversion (100%) of soybean oil under the operative conditions and proved to be always more selective (>90%) than Pd/C in giving decarbonylation products (alkanes C15 and C17). The catalyst resilience was evident in aqueous-phase reactions, where it maintained 86% conversion upon reuse, while Pd/C deactivated rapidly. Finally, industrial relevance was demonstrated extending the protocol to unrefined feedstocks such as olein residues and sewage scum, achieving 50–95% alkane yields.

为了解决对可持续生物燃料的迫切需求，在文献中首次使用了多壁碳纳米管负载的钯催化剂（Pd@MWCNTs）来促进脂肪酸和甘油三酯的脱氧（DO）以生产绿色柴油。在相对温和的条件下（250°C, 16 bar H2），以水为绿色溶剂进行反应。该催化剂采用纳米管氧化预处理方法，通过FTIR、SEM-EDX、BET、NH3-TPD、XPS、物理和化学吸附等技术对催化剂进行了表征。将Pd@MWCNTs与商品Pd/C的催化性能进行了比较，并从化学和形态特征上解释了不同的反应活性。Pd@MWCNTs给出了操作条件下大豆油的完全转化率（100%），并证明在得到脱羰产物（烷烃C15和C17）时总是比Pd/C更具选择性（>90%）。在水相反应中，催化剂的弹性很明显，在重复使用时保持86%的转化率，而Pd/C迅速失活。最后，证明了工业相关性，将该协议扩展到未精炼的原料，如油残和污水浮渣，达到50-95%的烷烃收率。

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引用次数: 0

Modification of electrical characteristics of CVD- graphene by Joule heating 焦耳加热法修饰CVD-石墨烯的电特性

IF 3.9 Q2 MATERIALS SCIENCE, MULTIDISCIPLINARY

Carbon Trends

Pub Date : 2025-09-24 DOI: 10.1016/j.cartre.2025.100577

M.G. Rybin , E.A. Guberna , V.A. Kamynin , Van Chuc Nguen , E.D. Obraztsova

This paper presents an approach for enhancing the electrical characteristics of graphene synthesized by chemical vapor deposition (CVD), through a direct resistive heating of the graphene channel by an electric current. This method efficiently purifies graphene of impurities and restores the material ideal structure through the desorption of adsorbed molecules. A graphene field-effect transistor was employed to characterize the graphene, specifically - to assess the mobility and concentration of charge carriers. The study investigates the impact of annealing temperature on both the concentration and type of charge carriers. It was found that CVD-synthesized graphene exhibits p-type conductivity, with the charge neutrality point (CNP) positioned above 80 Volts gate voltage at a 300 nm thickness of SiO₂. Annealing at 200 °C shifted this neutrality point to 0 Volts, switching the graphene to electrical neutrality. At higher annealing temperatures, n-type conductivity was achieved. Additionally, during the annealing process with current flow, there was a significant enhancement of the charge carriers mobility in graphene: for holes, mobility increased from 1000 cm²/(V·s) to 1800 cm²/(V·s), and for electrons - from 600 cm²/(V·s) to 1200 cm²/(V·s). Thus, the study reveals the effective method for removing impurities appeared after transfer of CVD graphene from copper foil to a dielectric substrate. This approach may be utilized in preparing samples for applications in microelectronics, optoelectronics, and related fields.

本文提出了一种通过电流对石墨烯通道进行直接电阻加热来提高化学气相沉积（CVD）合成的石墨烯电学特性的方法。该方法通过吸附分子的解吸，有效地净化石墨烯中的杂质，恢复材料的理想结构。石墨烯场效应晶体管被用来表征石墨烯，特别是评估电荷载流子的迁移率和浓度。研究了退火温度对载流子浓度和载流子类型的影响。发现cvd合成的石墨烯具有p型电导率，在厚度为300 nm的SiO2上，电荷中性点（CNP）位于80伏栅极电压以上。在200°C下退火将这个中性点转移到0伏，将石墨烯转换为电中性。在较高的退火温度下，实现了n型电导率。此外，在电流退火过程中，石墨烯中载流子的迁移率显著增强：对于空穴，迁移率从1000 cm²/（V·s）增加到1800 cm²/(V·s)，对于电子-从600 cm²/（V·s）增加到1200 cm²/（V·s）。因此，该研究揭示了去除CVD石墨烯从铜箔转移到介电基板后出现的杂质的有效方法。该方法可用于制备微电子学、光电子学及相关领域的样品。

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引用次数: 0

Confirmation of pentavalent carbon in protonated methane (CH5+ ): Insights from Molecular Handycam Technique 质子化甲烷（CH5+）中五价碳的确认：来自分子Handycam技术的见解

IF 3.9 Q2 MATERIALS SCIENCE, MULTIDISCIPLINARY

Carbon Trends

Pub Date : 2025-09-23 DOI: 10.1016/j.cartre.2025.100574

Moumita Dinda, Sudipta Nayak, Arijit Bag

The existence of pentavalent carbon has intrigued scientists since the discovery of CH

_{5}^{+}

in 1952 but remains elusive due to the lack of definitive evidence. The present study unveils the mystery through a comprehensive investigation of the structural and bonding nature of CH

_{5}^{+}

employing the newly developed Molecular Handycam Technique (MHT) by Bag and co-workers, focusing on its formation pathways and energetic favorability. Computational analysis at the coupled cluster theory (CCSD) level, we examine the formation of CH

_{5}^{+}

through the association of CH

_{3}^{+}

and H₂, compared to the protonation of methane. Our findings reveal a preference for the former pathway, highlighting distinct structural configurations, including a global minimum and two alternative geometries. We demonstrate the participation of higher orbitals of carbon (3d

_{z^{2}}

) and its interaction with the bond pair of the approaching H

_{2}

molecule in the formation and stabilization of the fifth C-H bond. This analytical approach provides critical insights into the expanded valency of carbon, which could lead to a new class of carbon compounds.

自1952年发现CH5+以来，五价碳的存在一直引起科学家们的兴趣，但由于缺乏明确的证据，仍然难以捉摸。本研究利用Bag和同事新开发的分子Handycam技术（MHT）对CH5+的结构和键合性质进行了全面的研究，重点研究了CH5+的形成途径和能量偏好。在耦合簇理论（CCSD）水平的计算分析中，我们研究了CH3+和H2结合形成CH5+的过程，并与甲烷的质子化反应进行了比较。我们的研究结果揭示了对前一种途径的偏好，突出了不同的结构配置，包括全局最小值和两种可选的几何形状。我们证明了碳（3dz2）的高轨道及其与接近的H2分子的键对的相互作用参与了第五碳氢键的形成和稳定。这种分析方法为碳的扩展价提供了关键的见解，这可能导致一类新的碳化合物。

{"title":"Confirmation of pentavalent carbon in protonated methane (CH5+ ): Insights from Molecular Handycam Technique","authors":"Moumita Dinda, Sudipta Nayak, Arijit Bag","doi":"10.1016/j.cartre.2025.100574","DOIUrl":"10.1016/j.cartre.2025.100574","url":null,"abstract":"<div><div>The existence of pentavalent carbon has intrigued scientists since the discovery of CH<span><math><msubsup><mrow></mrow><mrow><mn>5</mn></mrow><mrow><mo>+</mo></mrow></msubsup></math></span> in 1952 but remains elusive due to the lack of definitive evidence. The present study unveils the mystery through a comprehensive investigation of the structural and bonding nature of CH<span><math><msubsup><mrow></mrow><mrow><mn>5</mn></mrow><mrow><mo>+</mo></mrow></msubsup></math></span> employing the newly developed Molecular Handycam Technique (MHT) by Bag and co-workers, focusing on its formation pathways and energetic favorability. Computational analysis at the coupled cluster theory (CCSD) level, we examine the formation of CH<span><math><msubsup><mrow></mrow><mrow><mn>5</mn></mrow><mrow><mo>+</mo></mrow></msubsup></math></span> through the association of CH<span><math><msubsup><mrow></mrow><mrow><mn>3</mn></mrow><mrow><mo>+</mo></mrow></msubsup></math></span> and H<sub>2</sub>, compared to the protonation of methane. Our findings reveal a preference for the former pathway, highlighting distinct structural configurations, including a global minimum and two alternative geometries. We demonstrate the participation of higher orbitals of carbon (3d<span><math><msub><mrow></mrow><mrow><msup><mrow><mi>z</mi></mrow><mrow><mn>2</mn></mrow></msup></mrow></msub></math></span>) and its interaction with the bond pair of the approaching H<span><math><msub><mrow></mrow><mrow><mn>2</mn></mrow></msub></math></span> molecule in the formation and stabilization of the fifth C-H bond. This analytical approach provides critical insights into the expanded valency of carbon, which could lead to a new class of carbon compounds.</div></div>","PeriodicalId":52629,"journal":{"name":"Carbon Trends","volume":"21 ","pages":"Article 100574"},"PeriodicalIF":3.9,"publicationDate":"2025-09-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145158078","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Investigation of the porosity development in cellulose acetate modified PAN precursor fibers along the thermal conversion process to porous carbon fibers 醋酸纤维素改性PAN前驱体纤维在热转化成多孔碳纤维过程中孔隙度发展的研究

IF 3.9 Q2 MATERIALS SCIENCE, MULTIDISCIPLINARY

Carbon Trends

Pub Date : 2025-09-22 DOI: 10.1016/j.cartre.2025.100572

Robert Seidel-Greiff , Mohsen Sadeghi Bogar , Michael Kucher , Paul Bertram , Irina Kuznik , Iris Kruppke , Thomas Behnisch , Michael Thomas Müller , Dieter Fischer , Maik Gude , Robert Böhm , Chokri Cherif

Porous carbon fibers offer significant potential as multifunctional materials for super-capacitors and structural batteries due to their low density, high electrical conductivity, mechanical strength, and large specific surface area. This study investigates the development of porous carbon fibers derived from polyacrylonitrile precursor fibers modified with cellulose acetate, used as a pore-forming additive. The fibers were produced via a continuous wet-spinning process, followed by electron beam irradiation, thermal stabilization, and carbonization at three different temperatures: 700 °C, 800 °C, and 900 °C. The influence of these processing steps on porosity and mechanical performance was systematically analyzed. Morphological and structural characterization using scanning electron microscopy and nitrogen physisorption (Brunauer–Emmett–Teller method) revealed a transition from meso- and macro-porous architectures to dominant micro-porosity at the fibers surface. The highest specific surface area of 165.51

m^{2}

/g was obtained for the fiber carbonized at 700 °C, with pore sizes ranging from below 2 nm to above 80 nm. As the carbonization temperature increased, surface area decreased while mesoporosity became more pronounced. Raman spectroscopy was employed to evaluate the degree of carbon ordering. Mechanical testing demonstrated an inverse relationship between porosity and strength: tenacity increased from 2.85 cN/tex at 700 °C to 4.76 cN/tex at 900 °C, while elongation at break decreased. These findings highlight the critical trade-off between surface area-driven electrochemical functionality and the preservation of mechanical integrity. The results provide valuable insights into the optimization of porous carbon fibers for multifunctional applications in energy storage and structural systems.

多孔碳纤维由于其低密度、高导电性、机械强度和大比表面积等优点，在超级电容器和结构电池中具有巨大的潜力。本研究以聚丙烯腈前体纤维为原料，经醋酸纤维素改性制备多孔碳纤维。纤维是通过连续湿纺丝工艺，然后在700°C、800°C和900°C三种不同的温度下进行电子束辐照、热稳定和碳化来生产的。系统分析了这些工艺步骤对孔隙率和力学性能的影响。利用扫描电子显微镜和氮物理吸附（brunauer - emmet - teller方法）进行的形态和结构表征揭示了纤维表面从中孔和大孔结构到主要微孔结构的转变。700℃碳化纤维的比表面积最高，为165.51 m2/g，孔径范围从2 nm以下到80 nm以上。随着炭化温度的升高，比表面积减小，介孔现象更加明显。采用拉曼光谱法评价碳有序度。力学测试表明，孔隙率与强度呈反比关系：韧性从700℃时的2.85 cN/tex增加到900℃时的4.76 cN/tex，而断裂伸长率则下降。这些发现强调了表面积驱动的电化学功能和保持机械完整性之间的关键权衡。该结果为多孔碳纤维在储能和结构系统中的多功能应用的优化提供了有价值的见解。

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引用次数: 0

High-efficiency SO2 removal on Fe-impregnated activated carbon fiber-oxidized using low-concentration oxygen gas 低浓度氧气氧化铁浸渍活性炭纤维高效脱除SO2

IF 3.9 Q2 MATERIALS SCIENCE, MULTIDISCIPLINARY

Carbon Trends

Pub Date : 2025-09-15 DOI: 10.1016/j.cartre.2025.100570

Miftahul Huda , Ika Monika , Suganal Suganal , Amru Daulay , Edwin Akhdiat Daranin , Teuku Ishlah , Jin Miyawaki

Carbon-based adsorbents exhibit strong adsorption capabilities for low-concentration SO₂, and thus exhibit high-efficiency removal performance of SO₂ from exhaust gas. This study aims to further improve the SO₂ adsorption capacity of pitch-based activated carbon fiber (ACF) through controlled oxidation. Pristine ACF (PACF) and Fe-impregnated ACF (FeACF) were oxidized using low-concentration oxygen gas (2 % O₂ in N₂). The results showed that the oxidation of ACFs using low concentration O₂ increased the contents of oxygen-containing surface functional groups, and the oxidation of ACFs followed by heat treatment increased the specific surface area and widened the pore size. The adsorption capacity of PACF was 150.8 mL/g-ACF. Oxidization of FeACF at 450 °C for 1 hour and heat treatment at 1100 °C increased the SO₂ removal capacity, reaching 491.0 mL/g-ACF.

碳基吸附剂对低浓度SO2具有较强的吸附能力，对废气中SO2具有高效的去除效果。本研究旨在通过控制氧化进一步提高沥青基活性炭纤维（ACF）对SO2的吸附能力。采用低浓度氧气（2% O2 in N2）氧化原始ACF （PACF）和fe -浸渍ACF （FeACF）。结果表明：低浓度O2氧化后的ACFs表面含氧官能团含量增加，氧化后热处理后的ACFs比表面积增大，孔径扩大；PACF的吸附量为150.8 mL/g-ACF。450℃氧化1小时，1100℃热处理，SO2去除率提高，达到491.0 mL/g-ACF。

引用次数: 0

Catalytic synthesis of iron-doped graphitic aerogels from poly(phloroglucinol-terephthalaldehyde – urethane) precursors 以聚间苯三酚-对苯二甲酸乙二醛-聚氨酯为前驱体催化合成掺铁石墨气凝胶

IF 3.9 Q2 MATERIALS SCIENCE, MULTIDISCIPLINARY

Carbon Trends

Pub Date : 2025-09-15 DOI: 10.1016/j.cartre.2025.100573

Stephen Yaw Owusu, Rushi U. Soni , Chariklia Sotiriou-Leventis

We report a new class of graphitic carbon aerogel precursors based on iron oxide-doped poly(phloroglucinol-terephthalaldehyde–urethane) (T-POL/PU-FeOx) networks. The hybrid polymeric network incorporates a rigid aromatic triisocyanate, tris(4-isocyanatophenyl)methane, which reacts in situ with the hydroxyl groups of phloroglucinol to form a polyurethane-containing framework. Monolithic aerogels derived from this system undergo catalytic graphitization at significantly reduced temperatures (800–1500 °C) compared to conventional graphitization (2500–3300 °C). An oxidative ring fusion aromatization step (240 °C, air) prior to pyrolysis enhanced the degree of graphitization. The resulting graphitic aerogels were characterized by XRD, Raman spectroscopy, TGA, TEM, SEM, XPS, and N₂ sorption porosimetry. Compared to their purely phenolic analogs, graphitic carbons derived from the polyurethane-containing precursors exhibited enhanced porosity and higher surface areas. Optimal graphitization was achieved at 1500 °C, yielding aerogels primarily composed of 100 % (w/w) graphitic carbon. During pyrolysis, iron oxides facilitated carbothermal reduction to form Fe(0) nanoparticles embedded within the carbon matrix. These materials can find applications ranging from catalysis (e.g., oxygen reduction reaction - ORR) to biomedical applications (drug delivery). Additionally, none of the procedures for preparing these materials caused significant damage to the monoliths, making these materials useful for form-factor dependent applications.

我们报道了一类基于氧化铁掺杂聚间苯三酚-对苯二甲酸乙酯-聚氨酯（T-POL/PU-FeOx）网络的新型石墨碳气凝胶前驱体。混合聚合物网络包含刚性芳香三异氰酸酯，三（4-异氰酸atophenyl）甲烷，它与间苯三酚的羟基原位反应形成含聚氨酯的框架。与传统石墨化（2500-3300℃）相比，该体系衍生的单片气凝胶在显著降低的温度（800-1500℃）下进行催化石墨化。热解前的氧化环融合芳构化步骤（240℃，空气）提高了石墨化程度。采用XRD、拉曼光谱、TGA、TEM、SEM、XPS和n2吸附孔隙度等方法对所得石墨气凝胶进行了表征。与纯酚醛类似物相比，含聚氨酯前体衍生的石墨碳具有增强的孔隙率和更高的表面积。在1500°C的温度下，石墨化效果最佳，得到的气凝胶主要由100% （w/w）的石墨碳组成。在热解过程中，氧化铁促进碳热还原形成嵌入碳基体中的Fe(0)纳米颗粒。这些材料的应用范围从催化（例如氧还原反应- ORR）到生物医学应用（药物输送）。此外，制备这些材料的任何程序都不会对单体造成重大损害，这使得这些材料可用于依赖于形状因素的应用。

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引用次数: 0

Optimizing amoxicillin photodegradation with GO/TiO₂ nanocomposites via RSM, ANN, and ANFIS 通过RSM、ANN和ANFIS优化氧化石墨烯/ tio2纳米复合材料对阿莫西林的光降解

IF 3.9 Q2 MATERIALS SCIENCE, MULTIDISCIPLINARY

Carbon Trends

Pub Date : 2025-09-14 DOI: 10.1016/j.cartre.2025.100571

Seyed Ghasem Rezvannasab , Navid Safari , Abdol Mohammad Ghaedi

Visible-light photocatalysis has been reported to be one of the most effective means of wastewater treatment with high removal efficiency, process simplicity, and environmental friendliness. Photocatalytic degradation of Amoxicillin (AMX) was achieved successfully with GO/TiO₂ nanocomposites prepared via the hydrothermal process. The prepared nanocomposites were characterized by TEM, XRD, FE-SEM, EDS, and FTIR analysis. Three modeling approaches - adaptive neuro-fuzzy inference system (ANFIS), artificial neural network (ANN), and response surface methodology (RSM) - were employed to understand the relationships between input variables and photocatalytic degradation performance. R² values of 0.9876, 0.9159, and 0.7616 were obtained for RSM, ANN, and ANFIS, respectively, which indicates that the predictive capability of RSM and ANN models was better than ANFIS. The maximum degradation of amoxicillin of 91.01 % was realized within 105 min at 0.588 mg/mL GO/TiO₂ dosage, initial 36 mg/L AMX concentration, and pH 5.

可见光光催化具有去除率高、工艺简单、环境友好等优点，是目前处理废水最有效的方法之一。采用水热法制备了氧化石墨烯/TiO2纳米复合材料，成功地实现了对阿莫西林（AMX）的光催化降解。采用TEM、XRD、FE-SEM、EDS和FTIR对所制备的纳米复合材料进行了表征。采用自适应神经模糊推理系统（ANFIS）、人工神经网络（ANN）和响应面法（RSM）三种建模方法来理解输入变量与光催化降解性能之间的关系。RSM、ANN和ANFIS模型的R²分别为0.9876、0.9159和0.7616，表明RSM和ANN模型的预测能力优于ANFIS模型。在GO/TiO2用量为0.588 mg/mL、AMX初始浓度为36 mg/L、pH为5的条件下，105 min内对阿莫西林的最大降解率为91.01%。

引用次数: 0

Recent advances in coated carbon nanotube-reinforced metal matrix composites: Challenges, techniques, and performance enhancement 涂层碳纳米管增强金属基复合材料的最新进展：挑战、技术和性能增强

IF 3.9 Q2 MATERIALS SCIENCE, MULTIDISCIPLINARY

Carbon Trends

Pub Date : 2025-09-08 DOI: 10.1016/j.cartre.2025.100568

M.A. Mowazzem Hossain, Hamimul Islam Chowdhury, M.A. Shadab Siddiqui, Md. Sakib Hossain, M.S. Rabbi

Carbon nanotubes (CNTs) have attracted considerable scholarly attention over the past few decades as reinforcement materials in metal matrix composites (MMCs). This increasing interest is mainly due to their unique structural characteristics and exceptional electrical, mechanical, and thermal properties. However, weak interfacial bonding and agglomeration of CNTs significantly reduce their reinforcement efficiency. These issues can be solved by surface functionalization and coating techniques. The effectiveness of MMC applications is contingent upon successfully addressing and overcoming the associated challenges. This paper aims to explore the recent advances in coated CNT-reinforced MMCs to address these issues. The pros and cons of using various coating materials, including nickel (Ni), copper (Cu), and metal oxides, for coated CNTs as reinforcement material are comprehensively reviewed in this article. Moreover, various coated CNT fabrication techniques such as physical vapor deposition, chemical vapor deposition, electrodeposition, and electroless deposition are illustrated along with their merits and demerits. Among these methods, electrodeposition has proven to be the most widely used coating technique. Research findings show that Ni-coated CNT/magnesium (Mg) composites and titanium dioxide (TiO₂)-coated CNT/aluminum (Al) composites exhibit enhanced mechanical properties. On the contrary, silver-coated CNT/Cu composites exhibit superior electrical conductivity. The study emphasizes that selecting the appropriate coating metal depends primarily on the desired final properties of the composite. In addition, the paper highlights current challenges in the field and suggests potential future research avenues aimed at improving the performance of coated CNT-reinforced MMCs.

碳纳米管作为金属基复合材料（MMCs）的增强材料，在过去的几十年里引起了学术界的广泛关注。这种日益增长的兴趣主要是由于其独特的结构特征和卓越的电气、机械和热性能。然而，界面结合的弱和CNTs的团聚大大降低了CNTs的增强效率。这些问题可以通过表面功能化和涂层技术来解决。MMC应用的有效性取决于能否成功解决和克服相关挑战。本文旨在探讨涂层碳纳米管增强mmc的最新进展，以解决这些问题。本文全面综述了不同涂层材料，包括镍（Ni）、铜（Cu）和金属氧化物，作为CNTs涂层增强材料的优缺点。此外，各种涂层碳纳米管的制造技术，如物理气相沉积，化学气相沉积，电沉积和化学沉积，以及他们的优点和缺点的说明。在这些方法中，电沉积已被证明是应用最广泛的涂层技术。研究结果表明，ni包覆碳纳米管/镁（Mg）复合材料和二氧化钛（TiO2）包覆碳纳米管/铝（Al）复合材料的力学性能得到了增强。相反，镀银碳纳米管/铜复合材料表现出优异的导电性。研究强调，选择合适的涂层金属主要取决于期望的复合材料的最终性能。此外，本文还强调了该领域当前面临的挑战，并提出了旨在提高涂层碳纳米管增强mmc性能的潜在未来研究途径。

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引用次数: 0