306 results on '"carbon materials"'
Search Results
2. A-C/Au Film with Low Humidity Sensitivity of Friction by Forming Au Transfer Film.
- Author
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Pei, Lulu, Ji, Li, Li, Hongxuan, Cai, Haichao, and Xue, Yujun
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CARBON films , *CARBON-based materials , *TRANSMISSION electron microscopy , *MICROSCOPY , *RAMAN spectroscopy - Abstract
Amorphous carbon is recognized as an excellent lubricating material; however, its tribological properties are significantly influenced by humidity. To elucidate the mechanism underlying this humidity dependence and to propose a novel enhancement method, we investigated and compared the tribological properties of hydrogenated amorphous carbon (a-C:H) and amorphous carbon/gold (a-C/Au) composite films. First, the friction coefficient of these carbon films under different humidity conditions was tested using a rotational ball-on-disk tribometer. Subsequently, we analyzed the morphology and structure of the sliding interface employing optical microscopy (OM), Raman spectroscopy, transmission electron microscopy (TEM), and high-resolution transmission electron microscopy (HRTEM). Finally, first-principle calculations were carried out to calculate the adsorption energy of water molecules on different surfaces. The results indicate that the friction coefficient of a-C:H film and the area of transfer film increase with the increase of humidity. This phenomenon can be attributed to the fact that water molecules enhance the interaction between the a-C:H film and steel counterfaces. Notably, in contrast, the friction coefficient of a-C/Au film demonstrates low sensitivity to humidity due to the formation of an Au transfer film that exhibits weak interaction with water molecules. These findings provide a promising strategy for developing environment-adaptive amorphous carbon films and play an important role in promoting the development of intelligent lubricating film. [ABSTRACT FROM AUTHOR]
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- 2024
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3. Iron–Cobalt Bimetallic Metal–Organic Framework-Derived Carbon Materials Activate PMS to Degrade Tetracycline Hydrochloride in Water.
- Author
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Liu, Qin, Zhang, Huali, Zhang, Kanghui, Li, Jinxiu, Cui, Jiaheng, and Shi, Tongshan
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ORGANIC water pollutants ,CARBON-based materials ,WATER pollution ,BODIES of water ,HYDROTHERMAL synthesis ,REACTIVE oxygen species - Abstract
Organic pollutants entering water bodies lead to severe water pollution, posing a threat to human health. The activation of persulfate advanced oxidation processes using carbon materials derived from MOFs as substrates can efficiently treat wastewater contaminated with organic pollutants. This research uses NH
2 -MIL-101(Fe) as a substrate, doped with Fe2+ and Co2+ , to prepare Fe/Co-CNs through a one-step carbonization method. The surface morphology, pore structure, and chemical composition of Fe/Co-CNs were investigated using characterization techniques such as XRD, SEM, TEM, XPS, FT-IR, BET, and Raman. A comparative study was conducted on the performance of catalysts with different Fe/Co ratios in activating PMS for the degradation of organic pollutants, as well as the effects of various influencing factors (the dosage of Fe/Co-CNs, the amount of peroxymonosulfate (PMS), the initial pH of the solution, the TC concentration, and inorganic anions) on the catalyst's activation of persulfate for TC degradation. Through radical quenching experiments and post-degradation XPS analysis, the active radicals in the FeCo-CNs/PMS system were investigated to explain the possible mechanism of TC degradation in the Fe/Co-CNs/PMS system. The results indicate that Fe/Co-CNs-2 (with a Co2+ doping amount of 20%) achieves a degradation rate of 93.34% for TC (tetracycline hydrochloride) within 30 min when activating PMS, outperforming other Co2+ doping amounts. In addition, singlet oxygen (1 O2 ) is the main reactive species in the reaction system. [ABSTRACT FROM AUTHOR]- Published
- 2024
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4. Synthesis of Novel Fe-CNs-P/S Carbon Materials for Sustainable Water Treatment: Activation of Persulfate for Efficient Tetracycline Degradation.
- Author
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Zhang, Huali, Zhang, Kanghui, Liu, Qin, Shi, Tongshan, Cui, Jiaheng, and Li, Jinxiu
- Abstract
This study presents a novel Fe-CNs-P/S carbon composite material, synthesized by doping elements P and S into NH
2 -MIL-101 (Fe) using the carbonization method. The material's application in sustainable water treatment was evaluated, focusing on its effectiveness in activating persulfate for pollutant degradation. The research thoroughly investigates the synthesis process, structural characteristics, and performance in degrading pollutants. The results indicate that Fe-CNs-P/S-5 with 50% P and S co-doping is higher than that of other samples, where the degradation rate of TC in 30 min is as high as 98.11% under the optimum conditions, that is temperature at 25 °C, 0.05 g/L of catalyst concentration, and 0.2 g/L of PMS concentration. The composite material demonstrates robust versatility and stability, maintaining high degradation efficiency across multiple organic pollutants, with no significant reduction in catalytic performance after four cycles. Furthermore, the free radical quenching experiments display that the singlet oxygen1 O2 is the main active species. It is demonstrated that the doping of P and S play a role in the enhancement of PMS activation over the Fe-CNs-P/S catalyst. This material demonstrates remarkable efficacy in treating a range of organic contaminants and exhibits excellent reusability, presenting a promising approach for enhancing sustainability in water treatment applications. [ABSTRACT FROM AUTHOR]- Published
- 2024
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5. Carbon Materials with Different Dimensions Supported Pt Catalysts for Selective Hydrogenation of 3,4-Dichloronitrobenzene to 3,4-Dichloroaniline.
- Author
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Zhan, Nannan, Xiao, Yan, Chen, Xingkun, Tan, Yuan, and Ding, Yunjie
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CARBON-based materials , *CATALYST supports , *METAL catalysts , *ACTIVATED carbon , *DYNAMIC testing , *CARBON nanotubes - Abstract
In this study, carbon materials with different dimensions, including the typical one-dimensional (1D) carbon nanotube (CNT), two-dimensional (2D) graphene (GF), and three-dimensional (3D) activated carbon (AC), were investigated as a support for Pt catalysts for the selective hydrogenation of 3,4-dichloronitrobenzene (3,4-DCNB) to 3,4-dichloroaniline (3,4-DCAN). Notably, the Pt/CNT catalyst with the lowest dimension exhibited the best conversion of 3,4-DCNB under mild reaction conditions, followed by Pt/GF. Comprehensive characterizations, including XRD, TEM, XPS, and in situ CO DRIFTS, reveal that the dimension of carbon supports plays an important role in the particle size and electronic properties of Pt species, consequently affecting the catalytic performances of Pt catalysts. According to the results, electron-deficient Pt particles with small sizes are more favorable for the hydrogenation of 3,4-DCNB to 3,4-DCAN. In addition, dynamic tests and in situ DRIFTS of 3,4-DCNB indicated that the carbonaceous supports will largely influence the adsorption and activation capacity of the Pt catalysts, so that Pt loaded on CNT and GF are superior to that on the AC. We believe this study will provide good guidance for designing efficient carbon-supported metal catalysts for selective hydrogenation. [ABSTRACT FROM AUTHOR]
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- 2024
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6. Renewable Resources as Promising Materials for Obtaining Graphene Oxide-like Structures.
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Kuanyshbekov, Tilek, Akatan, Kydyrmolla, Guseinov, Nazim, Nemkaeva, Renata, Kurbanova, Bayan, Tolepov, Zhandos, Tulegenova, Malika, Kabdrakhmanova, Sana, and Zhilkashinova, Almira
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CARBON-based materials , *GRAPHENE oxide , *ACTIVATED carbon , *RAW materials , *RENEWABLE natural resources - Abstract
Currently, one of the topical directions in the field of production and application of graphene-like nanostructures is the use of renewable natural raw materials, which have unlimited resources for an economically efficient large-scale yield of a product with environmental safety. In this regard, we present the production of graphene oxide (GO) from a renewable natural raw material of plant biomass, birch activated carbon (BAC), and a comparison of the obtained physicochemical, mechanical, and electrical properties of birch activated carbon–graphene oxide (BAC–GO) and graphite–graphene oxide (G–GO) synthesized from the initial materials, BAC and graphite (G). Results obtained from this study confirm the successful oxidation of BAC, which correlates well with the physical–chemical dates of the G–GO and BAC–GO samples. Change in data after the oxidation of graphite and BAC was facilitated by the structure of the starting materials and, presumably, the location and content of functional oxygen-containing groups in the G–GO and BAC–GO chains. Based on the results, the application of a cost-effective, eco-friendly colloidal solution of nanodispersed BAC–GO from a plant biomass-based high-quality resource for producing large-scale nanostructured graphene is validated which has potential applicability in nanoelectronics, medicine, and other fields. [ABSTRACT FROM AUTHOR]
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- 2024
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7. Opportunities and Constraints of the Adsorption of Rare Earth Elements onto Pyrolytic Carbon-Based Materials: A Mini-Review.
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Nogueira, Miguel, Bernardo, Maria, Ventura, Márcia, Matos, Inês, Pinto, Filomena, and Lapa, Nuno
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RARE earth metals ,RARE earth oxides ,METALS ,CARBON-based materials ,ACTIVATED carbon ,PYROLYTIC graphite - Abstract
Rare earth elements (REEs), comprising seventeen metallic elements, including lanthanides, scandium, and yttrium, are indispensable for modern technological industries due to their unique properties. However, their supply is critically risky for the European Union, with 95% of global production concentrated in China, Brazil, Vietnam, Russia, India, and Australia. This mini-review examines the adsorption of REEs onto pyrolytic carbon-based materials as a sustainable recovery method from secondary raw materials. The review covers different types of carbon-based adsorbents used in several research works, such as activated carbon, chars, and biochar, and discusses their adsorption mechanisms and influencing factors. Comparative analyses of adsorption capacities highlight the significance of surface area and functionalization in enhancing adsorption efficiency. Despite promising results, the variability in adsorption performance due to experimental conditions and the scarcity of real-world application studies are noticed. This review underscores the need for further research using real e-waste leachates to validate the practical applicability of pyrolytic carbon-based adsorbents for REEs' recovery, aiming for an economically and environmentally sustainable solution. [ABSTRACT FROM AUTHOR]
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- 2024
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8. A Review of Carbon Anode Materials for Sodium-Ion Batteries: Key Materials, Sodium-Storage Mechanisms, Applications, and Large-Scale Design Principles.
- Author
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Jia, Qixing, Li, Zeyuan, Ruan, Hulong, Luo, Dawei, Wang, Junjun, Ding, Zhiyu, and Chen, Lina
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CARBON-based materials , *POROUS materials , *SODIUM ions , *LITHIUM-ion batteries , *ENERGY density - Abstract
Sodium-ion batteries (SIBs) have been proposed as a potential substitute for commercial lithium-ion batteries due to their excellent storage performance and cost-effectiveness. However, due to the substantial radius of sodium ions, there is an urgent need to develop anode materials with exemplary electrochemical characteristics, thereby enabling the fabrication of sodium-ion batteries with high energy density and rapid dynamics. Carbon materials are highly valued in the energy-storage field due to their diverse structures, low cost, and high reliability. This review comprehensively summarizes the typical structure; energy-storage mechanisms; and current development status of various carbon-based anode materials for SIBs, such as hard carbon, soft carbon, graphite, graphene, carbon nanotubes (CNTs), and porous carbon materials. This review also provides an overview of the current status and future development of related companies for sodium-ion batteries. Furthermore, it offers a summary and outlook on the challenges and opportunities associated with the design principles and large-scale production of carbon materials with high-energy-density requirements. This review offers an avenue for exploring outstanding improvement strategies for carbon materials, which can provide guidance for future application and research. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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9. A Study on the Pre-Hardened Shrinkage Reduction of Grout Using Carbon Materials.
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Lee, Jeong-Bae, Kim, Seong-Soo, Lee, Young-Jun, Jang, In-Soo, and Kim, Ju-Youn
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CARBON-based materials , *COMPRESSIVE strength , *CHARCOAL , *GROUTING , *CEMENT - Abstract
In this study, the characteristics of grout mixed with charcoal as an expansive agent were examined to reduce the pre-hardening shrinkage of cementitious materials. This study compared and reviewed the application of CSA, a conventional expansive agent, to grout. The setting time, fluidity, compressive strength, and pre-hardening shrinkage/expansion were evaluated to explore the usability of charcoal as an expansive agent. The test results confirmed that, as the incorporation rate of charcoal increased, the pre-hardening expansion rate of the grout also increased, making it more effective for pre-hardening expansion than the conventional expansive agent CSA. However, when charcoal was used as an expansive agent, the compressive strength decreased after hardening, indicating the need for caution regarding the amount of charcoal used. Furthermore, the pre-hardening shrinkage and expansion rates of the various types of charcoal used in this study showed some differences, suggesting the need for further research on the internal pore volume and pore size of the charcoal. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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10. Ferrocene-Modified Polyacrylonitrile-Containing Block Copolymers as Preceramic Materials.
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Heinz, Sebastian, Gemmer, Lea, Janka, Oliver, and Gallei, Markus
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MOLECULAR structure , *BLOCK copolymers , *CARBON-based materials , *X-ray powder diffraction , *CERAMIC materials , *POLYACRYLONITRILES , *POLYMER networks - Abstract
In the pursuit of fabricating functional ceramic nanostructures, the design of preceramic functional polymers has garnered significant interest. With their easily adaptable chemical composition, molecular structure, and processing versatility, these polymers hold immense potential in this field. Our study succeeded in focusing on synthesizing ferrocene-containing block copolymers (BCPs) based on polyacrylonitrile (PAN). The synthesis is accomplished via different poly(acrylonitrile-block-methacrylate)s via atom transfer radical polymerization (ATRP) and activators regenerated by electron transfer ATRP (ARGET ATRP) for the PAN macroinitiators. The molecular weights of the BCPs range from 44 to 82 kDa with dispersities between 1.19 and 1.5 as determined by SEC measurements. The volume fraction of the PMMA block ranges from 0.16 to 0.75 as determined by NMR. The post-modification of the BCPs using 3-ferrocenyl propylamine has led to the creation of redox-responsive preceramic polymers. The thermal stabilization of the polymer film has resulted in stabilized morphologies based on the oxidative PAN chemistry. The final pyrolysis of the sacrificial block segment and conversion of the metallopolymer has led to the formation of a porous carbon network with an iron oxide functionalized surface, investigated by scanning electron microscopy (SEM), energy dispersive X-ray mapping (EDX), and powder X-ray diffraction (PXRD). These findings could have significant implications in various applications, demonstrating the practical value of our research in convenient ceramic material design. [ABSTRACT FROM AUTHOR]
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- 2024
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11. From Waste to Resource: Evaluating Biomass Residues as Ozone-Catalyst Precursors for the Removal of Recalcitrant Water Pollutants.
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Graça, Cátia A. L. and Soares, Olívia Salomé Gonçalves Pinto
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CARBON-based materials ,COFFEE grounds ,WATER purification ,SURFACE area measurement ,ORANGE peel - Abstract
Five different biomass wastes—orange peel, coffee grounds, cork, almond shell, and peanut shell—were transformed into biochars (BCs) or activated carbons (ACs) to serve as adsorbents and/or ozone catalysts for the removal of recalcitrant water treatment products. Oxalic acid (OXL) was used as a model pollutant due to its known refractory character towards ozone. The obtained materials were characterized by different techniques, namely thermogravimetric analysis, specific surface area measurement by nitrogen adsorption, and elemental analysis. In adsorption experiments, BCs generally outperformed ACs, except for cork-derived materials. Orange peel BC revealed the highest adsorption capacity (Qe = 40 mg g
−1 ), while almond shell BC showed the best cost–benefit ratio at €0.0096 per mg of OXL adsorbed. In terms of catalytic ozonation, only ACs made from cork and coffee grounds presented significant catalytic activity, achieving pollutant removal rates of 72 and 64%, respectively. Among these materials, ACs made from coffee grounds reveal the best cost/benefit ratio with €0.02 per mg of OXL degraded. Despite the cost analysis showing that these materials are not the cheapest options, other aspects rather than the price alone must be considered in the decision-making process for implementation. This study highlights the promising role of biomass wastes as precursors for efficient and eco-friendly water treatment processes, whether as adsorbents following ozone water treatment or as catalysts in the ozonation reaction itself. [ABSTRACT FROM AUTHOR]- Published
- 2024
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12. Synthesis Method Comparison of N-Doped Carbons for Electrochemical Energy Storage.
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Palmbahs, Roberts, Lesnicenoks, Peteris, Knoks, Ainars, Vitola, Virginija, and Kleperis, Janis
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CARBON-based materials ,X-ray photoelectron spectroscopy ,ENERGY storage ,ELECTROCHEMICAL electrodes ,CARBON electrodes ,SUPERCAPACITORS - Abstract
This study investigates nitrogen-doped carbon synthesis and electrochemical properties as electrode material for energy storage devices, an additional focus of the work is on the electrochemical exfoliation synthesis of nitrogen-doped carbon using various precursors and doping methods. The physical properties of the synthesized sample are characterized using X-ray photoelectron spectroscopy, scanning electron microscopy, and Raman spectroscopy. The electrochemical properties of the N-doped carbons are studied using cyclic voltammetry and galvanostatic charge-discharge cycling. Finally, the work explores the potential application of the N-doped carbons as electrode material for energy storage devices, such as supercapacitors. The results show that N-doped carbons exhibit electrochemical performance superior to that of graphene oxide, with higher electrical capacitance. The results demonstrate the potential of N-doped carbons as high-performance electrode materials for electrochemical energy storage applications. This paper aims to explain the advantages of N-doping in carbon materials more precisely in graphene and the use of these materials in creating electrodes for application in supercapacitors and batteries. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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13. Facile Preparation of High-Performance Reduced Graphene Oxide (RGO)/Copper (Cu) Composites Based on Pyrolysis of Copper Formate.
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Shi, Zhendong, Yun, Qingwen, Zhang, Tong, Xing, Changsheng, Li, Jie, Wu, Yunzhong, and Wang, Lidong
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GRAPHENE oxide , *COPPER , *THERMAL conductivity , *FRACTURE strength , *YOUNG'S modulus , *SURFACE area - Abstract
Graphene has attracted much interest in many scientific fields because of its high specific surface area, Young's modulus, fracture strength, carrier mobility and thermal conductivity. In particular, the graphene oxide (GO) prepared by chemical exfoliation of graphite has achieved low-cost and large-scale production and is one of the most promising for Cu matrix composites. Here, we prepared a high strength, high electrical conductivity and high thermal conductivity reduced graphene oxide (RGO)/Cu composite by directly heating the GO/copper formate. The oxygen-containing functional groups and defects of RGO are significantly reduced compared with those of GO. The tensile yield strength and thermal conductivity of RGO/Cu composite with RGO volume fraction of 0.49 vol.% are as high as 553 MPa and 364 W/(m·K) at room temperature, respectively. The theoretical value of the tensile yield strength of the composite is calculated according to the strengthening mechanism, and the result shows that it agrees with the experimental value. After hot-rolling treatment, the ductility and conductivity of the composite materials have been greatly improved, and the ductility of the RGO/Cu composite with RGO volume fraction of 0.49 vol.% has been increased to four times the original. This work provides a highly efficient way to fabricate a high-performance RGO-reinforced Cu composite for commercial application. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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14. Development of Graphene Oxide-Based Anticancer Drug Combination Functionalized with Folic Acid as Nanocarrier for Targeted Delivery of Methotrexate.
- Author
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Yanikoglu, Reyhan, Karakas, Canan Yagmur, Ciftci, Fatih, Insel, Mert Akın, Karavelioglu, Zeynep, Varol, Rahmetullah, Yilmaz, Abdurrahim, Cakir, Rabia, Uvet, Hüseyin, and Ustundag, Cem Bulent
- Subjects
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ANTINEOPLASTIC combined chemotherapy protocols , *FOLIC acid , *DRUG delivery systems , *ECTOPIC pregnancy , *METHOTREXATE , *FOURIER transform infrared spectroscopy , *GRAPHENE oxide - Abstract
Graphene has become a prominent material in cancer research in recent years. Graphene and its derivatives also attract attention as carriers in drug delivery systems. In this study, we designed a graphene oxide (GO)-based methotrexate (MTX)-loaded and folic acid (FA)-linked drug delivery system. MTX and FA were bound to GO synthesized from graphite. MTX/FA/GO drug delivery system and system components were characterized using Fourier transform infrared spectroscopy (FTIR), differential calorimetric analysis (DSC), scanning electron microscopy (SEM), transmission electron microscopy (TEM), zeta potential analysis, and dimension measurement (DLS) studies. SEM and TEM images confirmed the nanosheet structure of GO synthesized from graphite, and it was shown that MTX/FA binding to GO transformed the two-dimensional GO into a three-dimensional structure. FTIR and DSC graphs confirmed that oxygen atoms were bound to GO with the formation of carboxylic, hydroxyl, epoxide, and carbonyl groups as a result of the oxidation of graphite, and GO was successfully synthesized. Additionally, these analyses showed that MTX and FA bind physicochemically to the structure of GO. The in vitro Franz diffusion test was performed as a release kinetic test. The release kinetics mathematical model and correlation coefficient (R2) of MTX-loaded GO/FA nanomaterials were found to be the Higuchi model and 0.9785, respectively. Stiffness analyses showed that adding FA to this release system facilitated the entry of the drug into the cell by directing the system to target cells. As a result of the stiffness analyses, the stiffness values of the control cell group, free MTX, and MTX/FA/GO applied cells were measured as 2.34 kPa, 1.87 kPa, and 1.56 kPa, respectively. According to these results, it was seen that MTX/FA/GO weakened the cancer cells. Combined use of the MTX/FA/GO drug delivery system had a higher cytotoxic effect than free MTX on the MDA-MB-231 breast cancer cell line. The results showed that the synthesized MTX/FA/GO material has promising potential in cancer cell-specific targeted therapy for MTX as a drug delivery system. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
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15. Advancements in Materials Science and Photocatalysts for Sustainable Development.
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Vadivel, Dhanalakshmi, Suryakumar, Swetha, Casella, Claudio, Speltini, Andrea, and Dondi, Daniele
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MATERIALS science , *SUSTAINABLE chemistry , *SUSTAINABILITY , *CHEMICAL reactions , *RENEWABLE natural resources , *SUSTAINABLE design , *SUSTAINABLE development - Abstract
Materials science and catalysis advancements play a critical role in achieving sustainable development by managing environmental, energy, and resource challenges. Catalyst design advancements focus on enhancing selectivity to achieve sustainable chemical reactions, reducing energy consumption. Designing catalysts that are environmentally friendly and biodegradable is increasingly gaining importance. This aligns with the principles of green chemistry and contributes to minimizing the environmental impact of catalytic processes. These advances, taken as a whole, lead to more sustainable and efficient processes in industries ranging from energy production to pollutant removal, fueling the advancement toward a more sustainable future. Photochemistry, that is, the activation of a stable compound (catalyst) into the highly reactive excited state, is of particular importance, since photons—especially when they come from solar light—are a green and renewable resource. This review article has provided the overall idea of the photocatalysts and materials under green chemistry perspective from the standpoint of the concept of sustainable development. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
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16. Hydrogen Storage System Attained by HCOOH-CO 2 Couple: Recent Developments in Pd-Based Carbon-Supported Heterogeneous Catalysts.
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Riquelme-García, Paula, Navlani-García, Miriam, and Cazorla-Amorós, Diego
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HETEROGENEOUS catalysts , *HYDROGEN storage , *FORMIC acid , *CARBON-based materials , *CARBON dioxide - Abstract
The present review revisits representative studies addressing the development of efficient Pd-based carbon-supported heterogeneous catalysts for two important reactions, namely, the production of hydrogen from formic acid and the hydrogenation of carbon dioxide into formic acid. The HCOOH-CO2 system is considered a promising couple for a hydrogen storage system involving an ideal carbon-neutral cycle. Significant advancements have been achieved in the catalysts designed to catalyze the dehydrogenation of formic acid under mild reaction conditions, while much effort is still needed to catalyze the challenging CO2 hydrogenation reaction. The design of Pd-based carbon-supported heterogeneous catalysts for these reactions encompasses both the modulation of the properties of the active phase (particle size, composition, and electronic properties) and the modification of the supports by means of the incorporation of nitrogen functional groups. These approaches are herein summarized to provide a compilation of the strategies followed in recent studies and to set the basis for a hydrogen storage system attained using the HCOOH-CO2 couple. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
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17. Hydrothermal Carbonization of Waste Biomass: A Review of Hydrochar Preparation and Environmental Application.
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Petrović, Jelena, Ercegović, Marija, Simić, Marija, Koprivica, Marija, Dimitrijević, Jelena, Jovanović, Aleksandar, and Janković Pantić, Jovana
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HYDROTHERMAL carbonization ,BIOMASS ,CARBON-based materials ,SOLID waste ,WASTE products ,CARBONIZATION ,BIOMASS gasification - Abstract
The concept of a bio-based economy has been adopted by many advanced countries around the world, and thermochemical conversion of waste biomass is recognized as the most effective approach to achieve this objective. Recent studies indicate that hydrothermal carbonization (HTC) is a promising method for the conversion of waste biomass towards novel carbonaceous materials known as hydrochars. This cost-effective and eco-friendly process operates at moderate temperatures (180–280 °C) and uses water as a reaction medium. HTC has been successfully applied to a wide range of waste materials, including lignocellulose biomass, sewage sludge, algae, and municipal solid waste, generating desirable carbonaceous products. This review provides an overview of the key HTC process parameters, as well as the physical and chemical properties of the obtained hydrochar. It also explores potential applications of produced materials and highlights the modification and functionalization techniques that can transform these materials into game-changing solutions for a sustainable future. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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18. Enzymolytic Lignin-Derived N-S Codoped Porous Carbon Nanocomposites as Electrocatalysts for Oxygen Reduction Reactions.
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Li, Zheng, Qu, Xia, Feng, Yuwei, Dong, Lili, Yang, Yantao, Lei, Tingzhou, and Ren, Suxia
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OXYGEN reduction , *CARBON-based materials , *ELECTROCATALYSTS , *NANOCOMPOSITE materials , *MELAMINE , *FUEL cells - Abstract
Currently, the development of nonmetallic oxygen reduction reaction (ORR) catalysts based on heteroatomic-doped carbon materials is receiving increaseing attention in the field of fuel cells. Here, we used enzymolytic lignin (EL), melamine, and thiourea as carbon, nitrogen, and sulfur sources and NH4Cl as an activator to prepare N- and S-codoped lignin-based polyporous carbon (ELC) by one-step pyrolysis. The prepared lignin-derived biocarbon material (ELC-1-900) possessed a high specific surface area (844 m2 g−1), abundant mesoporous structure, and a large pore volume (0.587 cm3 g−1). The XPS results showed that ELC-1-900 was successfully doped with N and S. ELC-1-900 exhibited extremely high activity and stability in alkaline media for the ORR, with a half-wave potential (E1/2 = 0.88 V) and starting potential (Eonset = 0.98 V) superior to those of Pt/C catalysts and most non-noble-metal catalysts reported in recent studies. In addition, ELC-1-900 showed better ORR stability and methanol tolerance in alkaline media than commercial Pt/C catalysts. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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19. Hydrogen Storage Properties of Ball Milled MgH 2 with Additives- Ni, V and Activated Carbons Obtained from Different By-Products.
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Grigorova, Eli, Markov, Pavel, Tsyntsarski, Boyko, Tzvetkov, Peter, and Stoycheva, Ivanka
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HYDROGEN storage , *ACTIVATED carbon , *BALL mills , *CARBON-based materials , *X-ray diffraction , *WASTE products - Abstract
The hydrogen sorption of materials based on 80 wt.% MgH2 with the addition of 15 wt.% Ni or V and 5 wt.% activated carbons synthesized from polyolefin wax, a waste product from polyethylene production (POW), walnut shells (CAN), and peach stones (CPS) prepared by milling under an inert Ar atmosphere for a period of 1 h, is investigated. All precursors are submitted to pyrolysis followed by steam activation in order to obtain the activated carbons. The hydrogen sorption evaluations are carried out for absorption at 473 and 573 K with pressure of 1 MPa and for desorption at 623 and 573 K with pressure of 0.15 MPa. The composition of the samples after milling and hydrogenation is monitored by X-ray diffraction analyses. The 80 wt.% MgH2–15 wt. %Ni–5 wt.% POW or CAN after absorption–desorption cycling and in a hydrogenated state at 573 K and 1 MPa are analyzed by TEM. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
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20. Fabrication and Characterization of Sulfonated Carbon Materials and Chitosan-Derived Functioned Carbon via Schiff's Base Process for Separation Purposes.
- Author
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Alghamdi, Ali S., Yusuf, Kareem, Habila, Mohamed A., and ALOthman, Zeid A.
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CARBON-based materials , *SURFACE energy , *SURFACE analysis , *CARBON , *SEPARATION (Technology) - Abstract
The Schiff bases reaction is applied to form various functioned carbon structures using renewable carbon from waste sources, Chitosan, 4-Amino-3-hydroxy-napthalene-1-sulphnic acid, and dimethyl amino benzaldehyde as starting materials. The formed functioned carbons were characterized by TEM, FTIR, XRD, and surface area analysis to assess their morphology, structure, porosity, and surface functional groups. In addition, the chromatographic-based thermodynamic analysis is applied to evaluate the surface energy and thermodynamic parameters during the separation of hydrocarbon species. Results indicated the formation of various carbon structures in convex-like shapes with diameters between 600 nm and 1500 nm, including side-building edges of diameter between 100 nm and 316 nm. The formed functioned carbon surfaces are rich with O-H, N=C, C=C, C=O, and C=S groups, as indicated by the FTIR. The function carbons are named carbon coated with Chitosan-derived covalent organic layer (C@Chitosan-COL) as well as Schiff's base-derived sulfonated carbon (Schiff's-C-S) in relation to the applied starting materials. The chromatographic-based thermodynamic analysis showed that the entropy changes of adsorption (ΔSA) increased with increasing chain length demonstrating less random movement and higher adsorption in both materials. The fabricated C@Chitosan-COL and Schiff's-C-S showed an efficient separation of hydrocarbon mixture including n-Nonane, n-Decane, n-Undecane, and n-Dodecane. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
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21. Carbon-Based Materials for Energy Storage Devices: Types and Characterization Techniques.
- Author
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Escobar-Teran, Freddy, Perrot, Hubert, and Sel, Ozlem
- Subjects
ENERGY storage ,CARBON ,ELECTROCHEMICAL analysis ,CONDUCTING polymers ,PERFORMANCE evaluation - Abstract
The urgent need for efficient energy storage devices (supercapacitors and batteries) has attracted ample interest from scientists and researchers in developing materials with excellent electrochemical properties. Electrode material based on carbon, transition metal oxides, and conducting polymers (CPs) has been used. Among these materials, carbon has gained wide attention in Electrochemical double-layer capacitors (EDLC) due to its variable morphology of pores and structural properties as well as its remarkable electrical and mechanical properties. In this context, the present review article summarizes the history of supercapacitors and the basic function of these devices, the type of carbon electrode materials, and the different strategies to improve the performance of these devices. In addition, we present different approaches to studying the charging mechanism of these devices through different electrochemical techniques existing in the literature, since a deeper understanding of the interfacial charge storage mechanisms is also crucial in the elaboration and performance of the electrode material. We make a comparison of the different techniques and present their advantages and challenges. Taking these advances into account, we consider that the coupling between two methods/techniques provides a better understanding of the charge storage mechanisms in energy storage devices. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
22. Graphite/Epoxy-Coated Flaky FeSiCr Powders with Enhanced Microwave Absorption.
- Author
-
Zhang, Haonan, Zhong, Xichun, Hu, Jinwen, He, Na, Xu, Hanxing, Liao, Xuefeng, Zhou, Qing, Liu, Zhongwu, and Ramanujan, Raju V.
- Subjects
CARBON-based materials ,MICROWAVES ,ELECTROMAGNETIC waves ,ABSORPTION ,ENERGY dissipation ,EPOXY resins ,POWDERS - Abstract
Flake-shaped FeSiCr (FFSC) material is expected to be a promising microwave absorbent due to its excellent magnetic properties and environmental resistance. By introducing carbon-based materials through suitable coatings, the electromagnetic parameters and energy loss can be tuned to improve the performance of FFSC. A facile solution-blending method was deployed to prepare graphite- and epoxy resin-encapsulated FFSC (FFSC@G/E) powders with a core–shell structure. FFSC@G
2000 /E showed excellent performance in the X band (8–12 GHz), a minimum reflection loss (RLmin ) of −42.77 dB at a thickness of 3 mm and a maximum effective absorption bandwidth (EABmax , RL < −10 dB) that reached 4.55 GHz at a thickness of 2.7 mm. This work provides a route for the production of novel high-performance microwave absorbers. [ABSTRACT FROM AUTHOR]- Published
- 2023
- Full Text
- View/download PDF
23. Green Synthesis of Hierarchically Porous Carbon Derived from Coal Tar Pitch for Enhanced Lithium Storage.
- Author
-
Zhang, Mengdi, Qu, Meng, Yuan, Wenhan, Mu, Jiawei, He, Zhengqiu, and Wu, Mingbo
- Subjects
COAL tar ,CARBON-based materials ,SUSTAINABILITY ,CARBON electrodes ,RAW materials ,NANOPORES - Abstract
Coal tar pitch (CTP) is a high-quality raw material for producing functional carbon materials owing to its high carbon yield and high degree of condensation. The rational structure regulation of CTP-derived carbon materials is paramount for their special application. Herein, a green template strategy is proposed to fabricate hierarchically porous carbon (HPC) and employ it as the anode material for lithium-ion batteries. It can be demonstrated that the mass ratio of the template (KHCO
3 ) and carbon source (CTP) significantly influences the microstructure and electrochemical performances of HPC. HPC-3 synthesized by a mass ratio of 3:1 shows a coral-like lamellar nanostructure with high specific surface area, developed nanopores, and ample defects, enabling fast and high-flux lithium storage. Thus, the HPC-3 electrode achieves an excellent rate capacity of 219 mAh g−1 at 10 A g−1 and maintains a high discharge capacity of 660 mAh g−1 after 1400 cycles at 1 A g−1 . This work takes a step towards the high-value-added and green utilization of CTP and offers a promising solution for the sustainable production of advanced carbon electrode materials. [ABSTRACT FROM AUTHOR]- Published
- 2023
- Full Text
- View/download PDF
24. Synthesis and Characterization of Nanocomposites Based on Carbon Materials and Transitional Oxides †.
- Author
-
Ţucureanu, Vasilica, Obreja, Cosmin Alexandru, Pachiu, Cristina, Brîncoveanu, Oana, and Matei, Alina
- Subjects
NANOCOMPOSITE materials ,OXIDE synthesis ,BIOSENSORS ,BIOMOLECULES ,CHEMICAL synthesis - Abstract
Nanostructured materials in the biomedical field are commonly used for diagnostics, drug delivery, therapy activation and monitoring therapeutic responses in real-time, thus maximizing the therapeutic benefits simultaneously with a minimally invasive effect and low toxicity. Electrochemical analysis and, implicitly, the development of materials for biosensors have become of vital importance for the monitoring of biomolecules. The conductivity of nanocomposites is usually determined by characteristics related to the concentration, size and dispersion of the nanoparticles. Generally, graphene's high surface energy and strong interactions moderate its uniform compatibility with different media. In the present paper, we propose the synthesis of yttrium oxide nanoparticles for developing nanocomposites based on transition oxides and carbon materials for electrochemical applications. The precipitation method was used to obtain nanostructured Y
2 O3 . The Hummer method was used for the synthesis of graphene material. After the activation step of the Y2 O3 surface, the ex-situ method was chosen to obtain the nanocomposites, allowing the insertion of oxide nanoparticles into the sheets of carbon materials. The developed materials were studied from a structural point of view using Raman and FTIR spectroscopy. The surface morphology, particle size and distribution of nanoparticles in the carbon material were studied using a field emission scanning electron microscope. The goniometric studies followed the wetting and percolation capacity of the nanocomposite. [ABSTRACT FROM AUTHOR]- Published
- 2023
- Full Text
- View/download PDF
25. Current Trends in the Use of Semiconducting Materials for Electrochemical Aptasensing.
- Author
-
Bousiakou, Leda, Al-Dosary, Omar, Economou, Anastasios, Subjakova, Veronika, and Hianik, Tibor
- Subjects
SEMICONDUCTORS ,BAND gaps ,ANALYTICAL chemistry ,CONDUCTING polymers ,APTAMERS - Abstract
Aptamers are synthetic single-stranded oligonucleotides that exhibit selective binding properties to specific targets, thereby providing a powerful basis for the development of selective and sensitive (bio)chemical assays. Electrochemical biosensors utilizing aptamers as biological recognition elements, namely aptasensors, are at the forefront of current research. They exploit the combination of the unique properties of aptamers with the advantages of electrochemical detection with the view to fabricate inexpensive and portable analytical platforms for rapid detection in point-of-care (POC) applications or for on-site monitoring. The immobilization of aptamers on suitable substrates is of paramount importance in order to preserve their functionality and optimize the sensors' sensitivity. This work describes different immobilization strategies for aptamers on the surface of semiconductor-based working electrodes, including metal oxides, conductive polymers, and carbon allotropes. These are presented as platforms with tunable band gaps and various surface morphologies for the preparation of low cost, highly versatile aptasensor devices in analytical chemistry. A survey of the current literature is provided, discussing each analytical method. Future trends are outlined which envisage aptamer-based biosensing using semiconductors. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
26. Laser Scribing Turns Plastic Waste into a Biosensor via the Restructuration of Nanocarbon Composites for Noninvasive Dopamine Detection.
- Author
-
Suriyaprakash, Jagadeesh, Huang, Yang, Hu, Zhifei, Wang, Hao, Zhan, Yiyu, Zhou, Yangtao, Thangavelu, Indumathi, and Wu, Lijun
- Subjects
DOPAMINE ,BIOSENSORS ,ELECTROCHEMICAL sensors ,LASERS ,SURFACE chemistry ,SCRIBES ,PLASTIC scrap - Abstract
The development of affordable and compact noninvasive point-of-care (POC) dopamine biosensors for the next generation is currently a major and challenging problem. In this context, a highly sensitive, selective, and low-cost sensing probe is developed by a simple one-step laser-scribing process of plastic waste. A flexible POC device is developed as a prototype and shows a highly specific response to dopamine in the real sample (urine) as low as 100 pmol/L in a broad linear range of 10
−10 –10−4 mol/L. The 3D topological feature, carrier kinetics, and surface chemistry are found to improve with the formation of high-density metal-embedded graphene-foam composite driven by laser irradiation on the plastic-waste surface. The development of various kinds of flexible and tunable biosensors by plastic waste is now possible thanks to the success of this simple, but effective, laser-scribing technique, which is capable of modifying the matrix's electronic and chemical composition. [ABSTRACT FROM AUTHOR]- Published
- 2023
- Full Text
- View/download PDF
27. A Review of the Carbon-Based Solid Transducing Layer for Ion-Selective Electrodes.
- Author
-
Wang, Peike, Liu, Haipeng, Zhou, Shiqiang, Chen, Lina, Yu, Suzhu, and Wei, Jun
- Subjects
- *
CARBON-based materials , *ELECTRODE performance , *CARBON composites , *ELECTRODES , *COMPOSITE materials - Abstract
As one of the key components of solid-contact ion-selective electrodes (SC-ISEs), the SC layer plays a crucial role in electrode performance. Carbon materials, known for their efficient ion–electron signal conversion, chemical stability, and low cost, are considered ideal materials for solid-state transducing layers. In this review, the application of different types of carbon materials in SC-ISEs (from 2007 to 2023) has been comprehensively summarized and discussed. Representative carbon-based materials for the fabrication of SC-ISEs have been systematically outlined, and the influence of the structural characteristics of carbon materials on achieving excellent performance has been emphasized. Finally, the persistent challenges and potential opportunities are also highlighted and discussed, aiming to inspire the design and fabrication of next-generation SC-ISEs with multifunctional composite carbon materials in the future. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
28. Photocatalytic CO 2 Conversion into Solar Fuels Using Carbon-Based Materials—A Review.
- Author
-
Sundar, Dhivya, Liu, Cheng-Hua, Anandan, Sambandam, and Wu, Jerry J.
- Subjects
- *
CARBON-based materials , *CARBON nanofibers , *CARBON dioxide , *TRANSITION metal complexes , *CARBON nanotubes , *CONDUCTING polymers , *ZIRCONIUM alloys - Abstract
Carbon materials with elusive 0D, 1D, 2D, and 3D nanostructures and high surface area provide certain emerging applications in electrocatalytic and photocatalytic CO2 utilization. Since carbon possesses high electrical conductivity, it expels the photogenerated electrons from the catalytic surface and can tune the photocatalytic activity in the visible-light region. However, the photocatalytic efficiency of pristine carbon is comparatively low due to the high recombination of photogenerated carriers. Thus, supporting carbon materials, such as graphene, CNTs (Carbon nanotubes), g-C3N4, MWCNs (Multiwall carbon nanotubes), conducting polymers, and its other simpler forms like activated carbon, nanofibers, nanosheets, and nanoparticles, are usually combined with other metal and non-metal nanocomposites to increase the CO2 absorption and conversion. In addition, carbon-based materials with transition metals and organometallic complexes are also commonly used as photocatalysts for CO2 reduction. This review focuses on developing efficient carbon-based nanomaterials for the photoconversion of CO2 into solar fuels. It is concluded that MWCNs are one of the most used materials as supporting materials for CO2 reduction. Due to the multi-layered morphology, multiple reflections will occur within the layers, thus enhancing light harvesting. In particular, stacked nanostructured hollow sphere morphologies can also help the metal doping from corroding. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
29. Progress of Nonmetallic Electrocatalysts for Oxygen Reduction Reactions.
- Author
-
Che, Zhongmei, Yuan, Yanan, Qin, Jianxin, Li, Peixuan, Chen, Yulei, Wu, Yue, Ding, Meng, Zhang, Fei, Cui, Min, Guo, Yingshu, and Wang, Shuai
- Subjects
- *
OXYGEN reduction , *ELECTROCATALYSTS , *DOPING agents (Chemistry) , *FUEL cells , *CATALYSTS , *ATOMS - Abstract
As a key role in hindering the large-scale application of fuel cells, oxygen reduction reaction has always been a hot issue and nodus. Aiming to explore state-of-art electrocatalysts, this paper reviews the latest development of nonmetallic catalysts in oxygen reduction reactions, including single atoms doped with carbon materials such as N, B, P or S and multi-doped carbon materials. Afterward, the remaining challenges and research directions of carbon-based nonmetallic catalysts are prospected. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
30. Bulk Resistivity of Materials in the Si/FeSi Furnace.
- Author
-
Hoover, Haley, Fromreide, Mads, Sævarsdottir, Gudrun, and Tangstad, Merete
- Subjects
SILICON carbide ,FURNACES ,ENTHALPY ,HEAT treatment ,COMPUTED tomography ,INSULATING materials ,CHARCOAL - Abstract
The formation of silicon carbide (SiC) and the energy distribution in the furnace are two important parameters in evaluating furnace operations. The energy distribution is determined by the resistivity of the materials in the furnace. This work aims to investigate the bulk resistivity of materials in the silicon (Si) furnace using both partially transformed carbon materials and raw charge mixes. In this study, the impact of temperature, SiC and Si content, and the addition of insulating charge materials are investigated up to 1600 °C using carbon materials as a base. The materials were treated under similar conditions to the industrial furnace. The resistivity of the carbon materials was between 7 and 17 mΩm at 1600 °C, where the char and coal were generally more conductive than the charcoal. The resistivity of partially transformed materials increased with conversion to SiC, and coal with a higher SiC content than 60% had an average resistivity at 1600 °C of around 30 mΩm. The resistivity then began to decrease as elemental Si formed in the pores. Up to 36%, the amount of Si did not affect the measured resistivity, but its presence likely causes a slight decrease. Computed tomography (CT) scans show that the SiC material is not visibly changing or transforming in the crucible during measurement. Comparing the SiC materials to carbon materials and SiC crust from the literature shows that partially transformed SiC will be as conductive or less conductive than carbon at high temperatures. At 1400 °C, the resistivity of the charge mixes that included char, quartz, woodchips, and silica–iron ore showed that the resistivity is directly proportional to the amount of the main conductive material, in this case, char. Temperature, transformation to SiC, and volume of conductive materials appear to influence the resistivity most heavily in this work. At higher temperatures, the effect of SiC content and heat treatment temperature is lessened as the range becomes smaller for these materials. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
31. Electrochemical Behavior of β-Cyclodextrin-Ni-MOF-74/Reduced Graphene Oxide Sensors for the Ultrasensitive Detection of Rutin.
- Author
-
Zhang, Li, Zhang, Mengting, Yang, Pingping, Zhang, Yin, Fei, Junjie, and Xie, Yixi
- Subjects
- *
GRAPHENE oxide , *FOURIER transform infrared spectroscopy , *RUTIN , *X-ray photoelectron spectroscopy , *METALLIC oxides - Abstract
Rutin, as a biological flavonoid glycoside, has very important medicinal value. The accurate and rapid detection of rutin is of great significance. Herein, an ultrasensitive electrochemical rutin sensor based on β-cyclodextrin metal–organic framework/reduced graphene oxide (β-CD-Ni-MOF-74/rGO) was constructed. The obtained β-CD-Ni-MOF-74 was characterized by X-ray diffraction spectroscopy (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FT-IR), and nitrogen adsorption and desorption. The β-CD-Ni-MOF-74/rGO presented good electrochemical properties benefiting from the large specific surface area and good adsorption enrichment effect of β-CD-Ni-MOF-74 and the good conductivity of rGO. Under optimal conditions for the detection of rutin, the β-CD-Ni-MOF-74/rGO/GCE showed a wider linear range (0.06–1.0 μM) and lower detection limit (LOD, 0.68 nM, (S/N = 3)). Furthermore, the sensor shows good accuracy and stability for the detection of rutin in actual samples. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
32. The Fast Formation of a Highly Active Homogeneous Catalytic System upon the Soft Leaching of Pd Species from a Heterogeneous Pd/C Precursor.
- Author
-
Galushko, Alexey S., Ilyushenkova, Valentina V., Burykina, Julia V., Shaydullin, Ruslan R., Pentsak, Evgeniy O., and Ananikov, Valentine P.
- Subjects
- *
TRANSITION metal catalysts , *LEACHING , *HETEROGENEOUS catalysts , *METAL nanoparticles , *RATE coefficients (Chemistry) - Abstract
Understanding the interface between soluble metal complexes and supported metal particles is important in order to reveal reaction mechanisms in a new generation of highly active homogeneous transition metal catalysts. In this study, we show that, in the case of palladium forming on a carbon (Pd/C) catalyst from a soluble Pd(0) complex Pd2dba3, the nature of deposited particles on a carbon surface turns out to be much richer than previously assumed, even if a very simple experimental procedure is utilized without the use of additional reagents and procedures. In the process of obtaining a heterogeneous Pd/C catalyst, highly active "hidden" metal centers are formed on the carbon surface, which are leached out by the solvent and demonstrate diverse reactivity in the solution phase. The results indicate that heterogeneous catalysts may naturally contain trace amounts of molecular monometallic centers of a different nature by easily transforming them to the homogeneous catalytic system. In line with a modern concept, a heterogenized homogeneous catalyst precursor was found to leach first, leaving metal nanoparticles mostly intact on the surface. In this study, we point out that the previously neglected soft leaching process contributes to high catalyst activity. The results we obtained demand for leaching to be reconsidered as a flexible tool for catalyst construction and for the rational design of highly active and selective homogeneous catalytic systems, starting from easily available heterogeneous catalyst precursors. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
33. Green Production of Biomass-Derived Carbon Materials for High-Performance Lithium–Sulfur Batteries.
- Author
-
Ma, Chao, Zhang, Mengmeng, Ding, Yi, Xue, Yan, Wang, Hongju, Li, Pengfei, and Wu, Dapeng
- Subjects
- *
LITHIUM sulfur batteries , *RENEWABLE natural resources , *CLEAN energy , *SOLAR cells , *PHYSISORPTION , *WIND power - Abstract
Lithium–sulfur batteries (LSBs) with a high energy density have been regarded as a promising energy storage device to harness unstable but clean energy from wind, tide, solar cells, and so on. However, LSBs still suffer from the disadvantages of the notorious shuttle effect of polysulfides and low sulfur utilization, which greatly hider their final commercialization. Biomasses represent green, abundant and renewable resources for the production of carbon materials to address the aforementioned issues by taking advantages of their intrinsic hierarchical porous structures and heteroatom-doping sites, which could attribute to the strong physical and chemical adsorptions as well as excellent catalytic performances of LSBs. Therefore, many efforts have been devoted to improving the performances of biomass-derived carbons from the aspects of exploring new biomass resources, optimizing the pyrolysis method, developing effective modification strategies, or achieving further understanding about their working principles in LSBs. This review firstly introduces the structures and working principles of LSBs and then summarizes recent developments in research on carbon materials employed in LSBs. Particularly, this review focuses on recent progresses in the design, preparation and application of biomass-derived carbons as host or interlayer materials in LSBs. Moreover, outlooks on the future research of LSBs based on biomass-derived carbons are discussed. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
34. Microporous Carbons Obtained via Solvent-Free Mechanochemical Processing, Carbonization and Activation with Potassium Citrate and Zinc Chloride for CO 2 Adsorption.
- Author
-
Saning, Amonrada, Dubadi, Rabindra, Chuenchom, Laemthong, Dechtrirat, Decha, and Jaroniec, Mietek
- Subjects
- *
ZINC chloride , *CARBON dioxide , *CARBONIZATION , *CITRATES , *POTASSIUM , *TANNINS - Abstract
In this study, the facile and sustainable synthesis of highly microporous carbons is explored to reduce the extensive use of harsh activating agents and solvents. The role of potassium citrate (PC) as a greener activating agent in addition to the conventional ZnCl2 is investigated in the mechanochemical solvent-free preparation of highly microporous carbon materials from chestnut tannin (CT), a biomass-type carbon precursor. A small amount of potassium citrate as a chemical activator coupled with CO2 activation at 700 °C afforded carbons with higher specific surface area (1256 m2 g−1) and larger micropore volume (0.54 cm3 g−1) as compared to the carbons activated with both PC and ZnCl2. The high microporosity of the PC-activated carbon materials, significantly enlarged after CO2 activation from micropore volume of 0.16 to 0.54 cm3 g−1, makes them favorable for CO2 adsorption, as evidenced by high adsorption capacity of 3.55 mmol g−1 at ambient conditions (25 °C, 1 bar). This study shows that the solvent-free mechanochemical processing of tannin in the presence of PC is a promising method for obtaining highly microporous carbon materials. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
35. Mesoporous Carbon-Based Materials for Enhancing the Performance of Lithium-Sulfur Batteries.
- Author
-
Wang, Fangzheng, Han, Yuying, Feng, Xin, Xu, Rui, Li, Ang, Wang, Tao, Deng, Mingming, Tong, Cheng, Li, Jing, and Wei, Zidong
- Subjects
- *
CARBON-based materials , *LITHIUM sulfur batteries , *MESOPOROUS materials , *ELECTRIC conductivity , *ENERGY density , *ENERGY storage - Abstract
The most promising energy storage devices are lithium-sulfur batteries (LSBs), which offer a high theoretical energy density that is five times greater than that of lithium-ion batteries. However, there are still significant barriers to the commercialization of LSBs, and mesoporous carbon-based materials (MCBMs) have attracted much attention in solving LSBs' problems, due to their large specific surface area (SSA), high electrical conductivity, and other unique advantages. The synthesis of MCBMs and their applications in the anodes, cathodes, separators, and "two-in-one" hosts of LSBs are reviewed in this study. Most interestingly, we establish a systematic correlation between the structural characteristics of MCBMs and their electrochemical properties, offering recommendations for improving performance by altering the characteristics. Finally, the challenges and opportunities of LSBs under current policies are also clarified. This review provides ideas for the design of cathodes, anodes, and separators for LSBs, which could have a positive impact on the performance enhancement and commercialization of LSBs. The commercialization of high energy density secondary batteries is of great importance for the achievement of carbon neutrality and to meet the world's expanding energy demand. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
36. Impact of Surface Structure on SEI for Carbon Materials in Alkali Ion Batteries: A Review.
- Author
-
Zhao, Xvtong, Chen, Ying, Sun, Hao, Yuan, Tao, Gong, Yinyan, Liu, Xinjuan, and Chen, Taiqiang
- Subjects
ALKALI metal ions ,SURFACE structure ,SURFACE passivation ,LITHIUM-ion batteries ,SOLID electrolytes ,FLUOROETHYLENE ,ALCOHOLS (Chemical class) - Abstract
Due to their low cost, suitable working potential and high stability, carbon materials have become an irreplaceable anode material for alkali ion batteries, such as lithium ion batteries, sodium ion batteries and potassium ion batteries. During the initial charge, electrolyte is reduced to form a solid electrolyte interphase (SEI) on the carbon anode surface, which is an electron insulator but a good ion conductor. Thus, a stable surface passivation is obtained, preventing the decomposition of electrolyte in the following cycles. It has been widely accepted that SEI is essential for the long-term performance of batteries, such as calendar life and cycle life. Additionally, the initial coulombic efficiency, rate capability as well as safety of the batteries are dramatically influenced by the SEI. Extensive research efforts have been made to develop advanced SEI on carbon materials via optimization of electrolytes, including solutes, solvents and additives, etc. However, SEI is produced via the catalytic decomposition of electrolyte by the surface of electrode materials. The surface structure of the carbon material is another important aspect that determines the structure and property of SEI, which little attention has been paid to in previous years. Hence, this review is dedicated to summarizing the impact of the surface structure of carbon materials on the composition, structure and electrochemical performance of the SEI in terms of surface atoms exposed, surface functionalization, specific surface area and pore structure. Some insights into the future development of SEI from the perspective of carbon surface are also offered. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
37. Carbon Materials as a Conductive Skeleton for Supercapacitor Electrode Applications: A Review.
- Author
-
Anil Kumar, Yedluri, Koyyada, Ganesh, Ramachandran, Tholkappiyan, Kim, Jae Hong, Sajid, Sajid, Moniruzzaman, Md, Alzahmi, Salem, and Obaidat, Ihab M.
- Subjects
- *
SURFACE conductivity , *CARBON electrodes , *CELLULOSE nanocrystals , *CARBON nanotubes , *SKELETON , *CARBON compounds , *SUPERCAPACITOR electrodes - Abstract
Supercapacitors have become a popular form of energy-storage device in the current energy and environmental landscape, and their performance is heavily reliant on the electrode materials used. Carbon-based electrodes are highly desirable due to their low cost and their abundance in various forms, as well as their ability to easily alter conductivity and surface area. Many studies have been conducted to enhance the performance of carbon-based supercapacitors by utilizing various carbon compounds, including pure carbon nanotubes and multistage carbon nanostructures as electrodes. These studies have examined the characteristics and potential applications of numerous pure carbon nanostructures and scrutinized the use of a wide variety of carbon nanomaterials, such as AC, CNTs, GR, CNCs, and others, to improve capacitance. Ultimately, this study provides a roadmap for producing high-quality supercapacitors using carbon-based electrodes. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
38. Advances in High-Temperature Molten Salt-Based Carbon Nanofluid Research.
- Author
-
Chen, Xia, Zhang, Mingxuan, Wu, Yuting, and Ma, Chongfang
- Subjects
- *
NANOFLUIDS , *SPECIFIC heat capacity , *HEAT storage , *FUSED salts , *HEAT transfer , *THERMAL conductivity - Abstract
Molten salt is an excellent medium for heat transfer and storage. The unique microstructure of carbon nanomaterials leads to good mechanical stability, low density, high thermal conductivity, and high strength, etc. The addition of carbon nanomaterials to molten salt to form molten salt nanofluid can remarkably enhance the specific heat capacity and thermal conductivity of molten salt and reduce the molten salt viscosity, which is of great importance to increase the heat storage density and reduce the heat storage cost. Nevertheless, some challenges remain in the study of such nanofluids. The main challenge is the dispersion stability of carbon nanomaterials. Therefore, to improve research on carbon nanofluids, this paper summarizes the progress of carbon-based molten salt nanofluid research worldwide including the preparation methods of molten salt nanofluids, the improvement of heat transfer performance, and the improvement of heat storage performance. The effects of carbon nanoparticle concentration, size, and type on the heat transfer and storage performance of molten salt are derived, and the effects of nanoparticle shape on the heat transfer performance of molten salt are analyzed while more promising preparation methods for carbon-based molten salt nanofluids are proposed. In addition, the future problems that need to be solved for high-temperature molten salt-based carbon nanofluids are briefly discussed. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
39. Recent Advances of Photoactive Near-Infrared Carbon Dots in Cancer Photodynamic Therapy.
- Author
-
Song, Jinxing, Gao, Xiaobo, Yang, Mei, Hao, Weiju, and Ji, Ding-Kun
- Subjects
- *
PHOTODYNAMIC therapy , *REACTIVE oxygen species , *CANCER treatment , *PHOTOSENSITIZERS , *CARBON - Abstract
Photodynamic therapy (PDT) is a treatment that employs exogenously produced reactive oxygen species (ROS) to kill cancer cells. ROS are generated from the interaction of excited-state photosensitizers (PSs) or photosensitizing agents with molecular oxygen. Novel PSs with high ROS generation efficiency is essential and highly required for cancer photodynamic therapy. Carbon dots (CDs), the rising star of carbon-based nanomaterial family, have shown great potential in cancer PDT benefiting from their excellent photoactivity, luminescence properties, low price, and biocompatibility. In recent years, photoactive near-infrared CDs (PNCDs) have attracted increasing interest in this field due to their deep therapeutic tissue penetration, superior imaging performance, excellent photoactivity, and photostability. In this review, we review recent progress in the designs, fabrication, and applications of PNCDs in cancer PDT. We also provide insights of future directions in accelerating the clinical progress of PNCDs. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
40. Recent Research Process of Carbon Engineering on Na 3 V 2 (PO 4) 3 for Sodium-Ion Battery Cathodes: A Mini Review.
- Author
-
He, Yaxuan and Li, Haibo
- Subjects
SODIUM ions ,ELECTRIC batteries ,THERMAL conductivity ,CATHODES ,ELECTRIC potential - Abstract
Owing to the 3D open framework, excellent structural stability, and high ionic conductivity, NASICON-type compounds are extensively employed as promising cathode materials for sodium-ion batteries (SIBs). Being one of the representative NASICON-type compounds, the Na
3 V2 (PO4 )3 delivers high theoretical capacity with an operating voltage exceeding 3.3 V, enabling it to be a good candidate for SIBs. Unfortunately, the Na3 V2 (PO4 )3 suffers from low electronic conductivity. In this work, we briefly review the recent research progress on novel carbon engineering strategies to enhance the electronic conductivity of Na3 V2 (PO4 )3 . Moreover, we will point out the issues relating to the development of NASICON cathode materials and put forward some suggestions. [ABSTRACT FROM AUTHOR]- Published
- 2023
- Full Text
- View/download PDF
41. 3D-Structured and Blood-Contact-Safe Graphene Materials.
- Author
-
Kaczmarek-Szczepańska, Beata, Michalska-Sionkowska, Marta, Binkowski, Pawel, Lukaszewicz, Jerzy P., and Kamedulski, Piotr
- Subjects
- *
GRAPHENE , *X-ray photoelectron spectroscopy , *RAMAN spectroscopy - Abstract
Graphene is a promising material that may be potentially used in biomedical applications, mainly for drug delivery applications. In our study, we propose an inexpensive 3D graphene preparation method by wet chemical exfoliation. The morphology of the graphene was studied by SEM and HRTEM. Moreover, the volumetric elemental composition (C, N, and H) of the materials was analyzed, and Raman spectra of prepared graphene samples were obtained. X-ray photoelectron spectroscopy, relevant isotherms, and specific surface area were measured. Survey spectra and micropore volume calculations were made. In addition, the antioxidant activity and hemolysis rate in contact with blood were determined. Activity against free radicals of graphene samples before and after thermal modification was tested using the DPPH method. The RSA of the material increased after graphene modification, which suggests that antioxidant properties were improved. All tested graphene samples caused hemolysis in the range of 0.28–0.64%. The results showed that all tested 3D graphene samples might be classified as nonhemolytic. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
42. Carbon-Based Materials and Their Applications in Sensing by Electrochemical Voltammetry.
- Author
-
Nguyen, Trong Danh, Nguyen, My Thi Ngoc, and Lee, Jun Seop
- Subjects
- *
CARBON-based materials , *VOLTAMMETRY , *ENVIRONMENTAL security , *BODY fluids , *ENVIRONMENTAL health - Abstract
In recent years, society has paid great attention to health care and environmental safety. Thus, research on advanced sensors for detecting substances that can harm health and the environment has been developed rapidly. Another popular target for detection techniques is disease-expressing materials that can be collected from body fluids. Carbon, which has outstanding electrochemical properties, can come from a variety of sources and has many morphological shapes, is nevertheless an environmentally friendly material. While carbon nanomaterial has become one of the most common targets for high-tech development, electrochemical voltammetry has proven to be an effective measurement method. Herein, the paper proposes a currently developed carbon nanomaterial along with research on a modified carbon material. Moreover, four common voltammetry methods and related works are also introduced. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
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43. A Comprehensive Review on Adsorption, Photocatalytic and Chemical Degradation of Dyes and Nitro-Compounds over Different Kinds of Porous and Composite Materials.
- Author
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Haleem, Abdul, Shafiq, Anum, Chen, Sheng-Qi, and Nazar, Mudasir
- Subjects
- *
CHEMICAL decomposition , *PHOTODEGRADATION , *POROUS materials , *COMPOSITE materials , *CARBON-based materials , *FLOCCULATION - Abstract
Dye and nitro-compound pollution has become a significant issue worldwide. The adsorption and degradation of dyes and nitro-compounds have recently become important areas of study. Different methods, such as precipitation, flocculation, ultra-filtration, ion exchange, coagulation, and electro-catalytic degradation have been adopted for the adsorption and degradation of these organic pollutants. Apart from these methods, adsorption, photocatalytic degradation, and chemical degradation are considered the most economical and efficient to control water pollution from dyes and nitro-compounds. In this review, different kinds of dyes and nitro-compounds, and their adverse effects on aquatic organisms and human beings, were summarized in depth. This review article covers the comprehensive analysis of the adsorption of dyes over different materials (porous polymer, carbon-based materials, clay-based materials, layer double hydroxides, metal-organic frameworks, and biosorbents). The mechanism and kinetics of dye adsorption were the central parts of this study. The structures of all the materials mentioned above were discussed, along with their main functional groups responsible for dye adsorption. Removal and degradation methods, such as adsorption, photocatalytic degradation, and chemical degradation of dyes and nitro-compounds were also the main aim of this review article, as well as the materials used for such degradation. The mechanisms of photocatalytic and chemical degradation were also explained comprehensively. Different factors responsible for adsorption, photocatalytic degradation, and chemical degradation were also highlighted. Advantages and disadvantages, as well as economic cost, were also discussed briefly. This review will be beneficial for the reader as it covers all aspects of dye adsorption and the degradation of dyes and nitro-compounds. Future aspects and shortcomings were also part of this review article. There are several review articles on all these topics, but such a comprehensive study has not been performed so far in the literature. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
44. Recent Progress in Biomass-Derived Carbon Materials for Li-Ion and Na-Ion Batteries—A Review.
- Author
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Molaiyan, Palanivel, Dos Reis, Glaydson Simões, Karuppiah, Diwakar, Subramaniyam, Chandrasekar M., García-Alvarado, Flaviano, and Lassi, Ulla
- Subjects
LITHIUM-ion batteries ,RENEWABLE energy transition (Government policy) ,CARBON-based materials ,ELECTRONIC equipment ,CARBON - Abstract
Batteries are the backbones of the sustainable energy transition for stationary off-grid, portable electronic devices, and plug-in electric vehicle applications. Both lithium-ion batteries (LIBs) and sodium-ion batteries (NIBs), most commonly rely on carbon-based anode materials and are usually derived from non-renewable sources such as fossil deposits. Biomass-derived carbon materials are extensively researched as efficient and sustainable anode candidates for LIBs and NIBs. The main purpose of this perspective is to brief the use of biomass residues for the preparation of carbon anodes for LIBs and NIBs annexed to the biomass-derived carbon physicochemical structures and their aligned electrochemical properties. In addition, an outlook and some challenges faced in this promising area of research is presented. This review enlightens the readers with valuable insights and a reasonable understanding of issues and challenges faced in the preparation, physicochemical properties, and application of biomass-derived carbon materials as anode candidates for LIBs and NIBs. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
45. Influence of the Method of Fe Deposition on the Surface of Hydrolytic Lignin on the Activity in the Process of Its Conversion in the Presence of CO 2.
- Author
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Medvedev, Artem A., Kustov, Alexander L., Beldova, Daria A., Kalmykov, Konstantin B., Mashkin, Mikhail Yu., Shesterkina, Anastasia A., Dunaev, Sergey F., and Kustov, Leonid M.
- Subjects
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CARBON dioxide , *LIGNINS , *LIGNIN structure , *METALLIC surfaces , *IRON , *METAL catalysts , *ECONOMIC indicators - Abstract
Hydrolytic lignin is one of the non-demanded carbon materials. Its CO2-assisted conversion is an important way to utilize it. The use of the catalysts prepared by metal deposition on the surface of hydrolytic lignin makes it possible to apply milder conditions of the conversion process with CO2 and to improve the economic indicators. The development of methods of deposition of the active phase is a problem of high importance for any heterogeneous catalytic processes. This work aimed at investigating the influence of the conditions of iron deposition on the surface of hydrolytic lignin on the process of CO2-assisted conversion of lignin. Different Fe precursors (Fe(NO3)3, FeSO4, Fe2(SO4)3), solvents (water, isopropanol, acetone, and ethanol), and concentrations of the solution were used; the properties of Fe/lignin composites were estimated by SEM, EDX, TEM, XRD methods and catalytic tests. All the prepared samples demonstrate a higher conversion compared to starting lignin itself in the carbon dioxide-assisted conversion process. The carbon dioxide conversion was up to 66% at 800 °C for the sample prepared from Fe(NO3)3 using a twofold water volume compared to incipient wetness water volume as a solvent (vs. 39% for pure lignin). [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
46. Assessment of Corrosion Protection Performance of FeOOH/Fe 3 O 4 /C Composite Coatings Formed In Situ on the Surface of Fe Metal in Air-Saturated 3.5 wt.% NaCl Solution.
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Huang, Lina, Luo, Qi, and He, Yan
- Subjects
- *
COMPOSITE coating , *FERRIC oxide , *METALLIC surfaces , *CARBON composites , *METALLIC composites - Abstract
The purpose of this work is to evaluate the corrosion-inhibition behavior of deposited carbon and some iron-oxide hybrid coatings which derived from the in situ deposition method on the surface of Fe foil. Various contents of precursor methane gas were deposited over a mild iron foil substrate and formed different composites. It was found that the incorporation of C into the Fe matrix led to a thin film on the surface of the matrix and produced an anti-corrosion effect. Electrochemical impedance spectroscopy (EIS), potentiodynamic polarization and potentiometric tests were used to compare the corrosion behaviors of the films in air-saturated 3.5 wt.% NaCl solution. According to the results, Fe-oxide- and C-composite-coated iron foil has a much higher corrosion resistance than the raw blank sample without the addition of C. Generally, the corrosion charge transfer resistance of one kind of iron oxide coated with carbon layers of several nanometers was enhanced up to 28,379 times (Rct changes from 1487 Ω cm2 to 4.22 × 107 Ω cm2), which is the biggest improvement so far. The maximum protection efficiency was obtained for the in situ grown coating prepared by 10 and 15 sccm CH4 precursor gas (eta = 100%). In conclusion, an iron oxide and carbon composite was found to be a great candidate for applications in the corrosion-resistance area. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
47. Electrochemical Reduction of CO 2 to C1 and C2 Liquid Products on Copper-Decorated Nitrogen-Doped Carbon Nanosheets.
- Author
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Suliman, Munzir H., Yamani, Zain H., and Usman, Muhammad
- Subjects
- *
ELECTROLYTIC reduction , *NANOSTRUCTURED materials , *CARBON dioxide , *ATMOSPHERIC carbon dioxide , *DOPING agents (Chemistry) , *NUCLEAR magnetic resonance , *STANDARD hydrogen electrode - Abstract
Due to the significant rise in atmospheric carbon dioxide (CO2) concentration and its detrimental environmental effects, the electrochemical CO2 conversion to valuable liquid products has received great interest. In this work, the copper-melamine complex was used to synthesize copper-based electrocatalysts comprising copper nanoparticles decorating thin layers of nitrogen-doped carbon nanosheets (Cu/NC). The as-prepared electrocatalysts were characterized by XRD, SEM, EDX, and TEM and investigated in the electrochemical CO2 reduction reaction (ECO2RR) to useful liquid products. The electrochemical CO2 reduction reaction was carried out in two compartments of an electrochemical H-Cell, using 0.5 M potassium bicarbonate (KHCO3) as an electrolyte; nuclear magnetic resonance (1H NMR) was used to analyze and quantify the liquid products. The electrode prepared at 700 °C (Cu/NC-700) exhibited the best dispersion for the copper nanoparticles on the carbon nanosheets (compared to Cu/NC-600 & Cu/NC-800), highest current density, highest electrochemical surface area, highest electrical conductivity, and excellent stability and faradic efficiency (FE) towards overall liquid products of 56.9% for formate and acetate at the potential of −0.8V vs. Reversible Hydrogen Electrode (RHE). [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
48. The Influence of Processing Conditions on Gas Transport and Thermal Properties of Graphite Foil Compressed from Exfoliated Graphite.
- Author
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Ivanov, Andrei V., Yurkov, Andrey L., Kalachev, Igor L., Maksimova, Natalia V., Malakho, Artem P., Volkova, Svetlana I., and Avdeev, Victor V.
- Subjects
THERMAL properties ,GRAPHITE ,GRAPHITE intercalation compounds ,NUCLEAR industry ,THERMAL stability ,MANUFACTURING processes - Abstract
Graphite foil (GF) compressed from exfoliated graphite (EG) is a sealing material, which is used in nuclear energy and the chemical industry. The preparation of graphite foil is a complex process, which includes the intercalation of graphite, water washing, thermal exfoliation and pressing of intermediate products. The preparation conditions significantly influence the structure of the material and its physicochemical properties. Thus, the aim of work was to reveal the correlation between GF processing conditions, its crystalline structure, porosity and gas permeability as well as thermal stability. Sealability of the material is connected with low value of gas permeability, while thermal stability allows use of the material in high-temperature processes. Optimization of these parameters allow for the obtaining of a reliable material and expanding of the areas of its application. Exfoliated graphite for GF was prepared at different temperatures of 600, 800 and 1000 °C from the H
2 SO4 –graphite intercalation compound (GIC) of II, III, IV stages. The influence of the GF processing conditions (the GIC stage number and the EG preparation temperature) on the main properties (gas permeability and thermal oxidation stability) of the sealing materials was investigated. A decrease in GIC stage number leads to the formation of GF with lower macroporosity and lower nitrogen and hydrogen permeability. However, an increase in GF surface area leads to an increase in the rate of GF oxidation by air oxygen. An increase in the EG preparation temperature from 800 to 1000o C results in the formation of EG with a developed micro- and mesoporosity and increasing GF gas permeability. A decrease in EG preparation temperature down to 600 °C promotes the formation of new transport macropores in GF. The change of the EG preparation temperature has little effect on GF oxidation stability. [ABSTRACT FROM AUTHOR]- Published
- 2023
- Full Text
- View/download PDF
49. Synthesis and Applications of Dimensional SnS 2 and SnS 2 /Carbon Nanomaterials.
- Author
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Diko, Catherine Sekyerebea, Abitonze, Maurice, Liu, Yining, Zhu, Yimin, and Yang, Yan
- Subjects
- *
NANOSTRUCTURED materials , *ENERGY storage , *VISIBLE spectra , *ENERGY conversion , *ENERGY density - Abstract
Dimensional nanomaterials can offer enhanced application properties benefiting from their sizes and morphological orientations. Tin disulfide (SnS2) and carbon are typical sources of dimensional nanomaterials. SnS2 is a semiconductor with visible light adsorption properties and has shown high energy density and long cycle life in energy storage processes. The integration of SnS2 and carbon materials has shown enhanced visible light absorption and electron transmission efficiency. This helps to alleviate the volume expansion of SnS2 which is a limitation during energy storage processes and provides a favorable bandgap in photocatalytic degradation. Several innovative approaches have been geared toward controlling the size, shape, and hybridization of SnS2/Carbon composite nanostructures. However, dimensional nanomaterials of SnS2 and SnS2/Carbon have rarely been discussed. This review summarizes the synthesis methods of zero-, one-, two-, and three-dimensional SnS2 and SnS2/Carbon composite nanomaterials through wet and solid-state synthesis strategies. Moreover, the unique properties that promote their advances in photocatalysis and energy conversion and storage are discussed. Finally, some remarks and perspectives on the challenges and opportunities for exploring advanced SnS2/Carbon nanomaterials are presented. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
50. A Novel Approach to Charcoal Fine Waste: Sustainable Use as Filling of Polymeric Matrices.
- Author
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Delatorre, Fabíola Martins, Cupertino, Gabriela Fontes Mayrinck, Oliveira, Michel Picanço, da Silva Gomes, Felipe, Profeti, Luciene Paula Roberto, Profeti, Demetrius, Júnior, Mário Guimarães, de Azevedo, Márcia Giardinieri, Saloni, Daniel, and Júnior, Ananias Francisco Dias
- Subjects
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CHARCOAL , *POLYMERIC composites , *FOURIER transform infrared spectroscopy , *X-ray photoelectron spectroscopy , *MODULUS of elasticity - Abstract
Most composites produced come from fossil fuel sources. Renewable strategies are needed for the production of composites. Charcoal fines are considered waste and an alternative for the production of biocomposites. The charcoal fines resulting from the pyrolysis of any biomass are an efficient alternative for the production of green composites. Studies to understand how the pyrolysis parameters influence the properties of this material for the production of biocomposites are necessary. Charcoal has a high carbon content and surface area, depending on final production temperatures. This study aims to evaluate charcoal fines as potential reinforcing agents in biocomposites. This study investigated for the first time charcoal fines from three pyrolysis temperatures (400, 600, and 800 °C) to identify the most suitable charcoal for use as a raw material in the production of carbon biocomposites with 30% by weight incorporated into a polyester matrix composite. Apparent density, porosity, morphology, and immediate chemical composition and Fourier transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS) of charcoal fines were evaluated. The charcoal fines produced at 800 °C showed interesting potential as polymeric matrix fillers due to their higher porosity (81.08%), fixed carbon content (96.77%), and hydrophobicity. The biocomposites were analyzed for flexural and tensile strength and scanning electron microscopy. The results revealed an improvement in resistance at elevated temperatures, especially at 800 °C, with higher breaking strength (84.11 MPa), modulus of elasticity (4064.70 MPa), and traction (23.53 MPa). Scanning electron microscopy revealed an improvement in morphology, with a decrease in roughness at 800 °C, which caused greater adhesion to the polyester matrix. These results revealed a promising new biocomposite compared to other natural lignocellulosic polymeric composites (NLFs) in engineering applications. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
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