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doi: 10.1016/S1872-5805(23)60772-3
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For the detection of Cu(II), an electrochemical sensor based on ion imprinted polymers as recognition element is prepared by combining surface imprinting with electrochemical polymerization deposition. The sensor is modified by ion-imprinted magnetic carbon nanospheres with specific selectivity and sensitivity towards Cu(II). The morphology and structure of the obtained imprinted materials are characterized and analysed. The electrochemical performance of the sensors shows that, compared with non-imprinted electrode and bare electrode, the imprinted electrode has stronger selectivity and higher sensitivity towards Cu(II). With the relative concentration of Cu(II) changing from 10−6 to 10−10 mol L−1, the detection limit of the sensor is as low as 5.138×10−16 mol L−1 (S/N=3). Additionally, the sensor features good anti-interference, reproducibility, and stability, which provides a feasible strategy for electrochemical detection of metal ions.
For the detection of Cu(II), an electrochemical sensor based on ion imprinted polymers as recognition element is prepared by combining surface imprinting with electrochemical polymerization deposition. The sensor is modified by ion-imprinted magnetic carbon nanospheres with specific selectivity and sensitivity towards Cu(II). The morphology and structure of the obtained imprinted materials are characterized and analysed. The electrochemical performance of the sensors shows that, compared with non-imprinted electrode and bare electrode, the imprinted electrode has stronger selectivity and higher sensitivity towards Cu(II). With the relative concentration of Cu(II) changing from 10−6 to 10−10 mol L−1, the detection limit of the sensor is as low as 5.138×10−16 mol L−1 (S/N=3). Additionally, the sensor features good anti-interference, reproducibility, and stability, which provides a feasible strategy for electrochemical detection of metal ions.
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doi: 10.1016/S1872-5805(23)60752-8
摘要:
超级电容器用多孔炭电极的表面改性与优化是实现其优异性能的关键。本文以煤化学工业的固体副产物为碳源，利用二维层状双氢氧化物（MgAl-LDH）的刚性约束作用耦合KOH活化工艺成功的制备了二维富氧多孔炭纳米材料（OPCN）。系统研究了碳化温度对OPCN样品微观结构和表面特性的影响，通过SEM、TEM、氮气吸脱附测试以及元素分析等表征手段对碳材料的结构/组成和表面特性进行分析表明，经700 °C碳化获得的碳材料样品（OPCN-700）具有较高的氧含量（24.4 wt%）和大的比表面积（2 388 m2 g−1），并表现出良好的润湿性。同时，OPCN-700样品丰富的微孔和二维纳米片结构为电解质离子提供了有效的储存和传输途径。作为超级电容器的电极材料，在电流密度为0.5 A g−1时，其比电容高达382 F g−1，并呈现出优异的倍率性能和循环稳定性。该技术策略为富氧原子掺杂二维多孔炭材料的可控制备与水系储能器件的设计构建提供了新思路。
超级电容器用多孔炭电极的表面改性与优化是实现其优异性能的关键。本文以煤化学工业的固体副产物为碳源，利用二维层状双氢氧化物（MgAl-LDH）的刚性约束作用耦合KOH活化工艺成功的制备了二维富氧多孔炭纳米材料（OPCN）。系统研究了碳化温度对OPCN样品微观结构和表面特性的影响，通过SEM、TEM、氮气吸脱附测试以及元素分析等表征手段对碳材料的结构/组成和表面特性进行分析表明，经700 °C碳化获得的碳材料样品（OPCN-700）具有较高的氧含量（24.4 wt%）和大的比表面积（2 388 m2 g−1），并表现出良好的润湿性。同时，OPCN-700样品丰富的微孔和二维纳米片结构为电解质离子提供了有效的储存和传输途径。作为超级电容器的电极材料，在电流密度为0.5 A g−1时，其比电容高达382 F g−1，并呈现出优异的倍率性能和循环稳定性。该技术策略为富氧原子掺杂二维多孔炭材料的可控制备与水系储能器件的设计构建提供了新思路。
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doi: 10.1016/S1872-5805(23)60741-3
摘要:
It is meaningful to find a toughener with a low dosage and effective improvement of interlaminar toughness in carbon fiber composites. In this paper, the toughening effect of phenolphthalein-based poly (ether sulfone) (PES-C) on E51/ DETDA epoxy and its carbon fiber composites (CFCs) was investigated. The SEM results showed that PES-C/epoxy blends formed sea-island phase and bicontinuous phase structure, which were associated with reaction-induced phase separation. After adding 15 phr PES-C, the glass transition temperature (Tg) of blends was increased by 51.5 °C. Meanwhile, the flexural strength, impact strength and fracture toughness of the blends were improved by 41.1%, 186.2% and 42.7%, respectively. These improvements could be attributed to the phase separation structure of the PES-C/epoxy system. Moreover, PES-C film was used to improve the mode-II fracture toughness (GIIC) of CFCs. GIIC value of the 7 μm PES-C film toughened laminate was improved by 80.3% than that of control laminate. The increase in GIIC could be attributed to cohesive failure and plastic deformation in the interleaving region.
It is meaningful to find a toughener with a low dosage and effective improvement of interlaminar toughness in carbon fiber composites. In this paper, the toughening effect of phenolphthalein-based poly (ether sulfone) (PES-C) on E51/ DETDA epoxy and its carbon fiber composites (CFCs) was investigated. The SEM results showed that PES-C/epoxy blends formed sea-island phase and bicontinuous phase structure, which were associated with reaction-induced phase separation. After adding 15 phr PES-C, the glass transition temperature (Tg) of blends was increased by 51.5 °C. Meanwhile, the flexural strength, impact strength and fracture toughness of the blends were improved by 41.1%, 186.2% and 42.7%, respectively. These improvements could be attributed to the phase separation structure of the PES-C/epoxy system. Moreover, PES-C film was used to improve the mode-II fracture toughness (GIIC) of CFCs. GIIC value of the 7 μm PES-C film toughened laminate was improved by 80.3% than that of control laminate. The increase in GIIC could be attributed to cohesive failure and plastic deformation in the interleaving region.
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doi: 10.1016/S1872-5805(23)60732-2
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2D laminated carbon cloth as reinforcement, furfurone resin mixed with three inorganic powders such as silicon powder, carbon powder and silicon carbide powder, carbon/carbon-silicon carbide (C/C-SiC) composites were prepared through impregnation, hot-pressing with curing, carbonization and high-temperature heat treatment processes. The effects of addition of silicon powder, carbon powder and silicon carbide powder as well as subsequent chemical vapor infiltration (CVI) treatment on density, microstructure and bending strength of C/C-SiC composites were studied by scanning electron microscope (SEM), multifunctional density , X-ray diffraction (XRD) and universal mechanical testing machine. The results showed that the silicon carbide particles formed by the addition of silicon powder, carbon powder and silicon carbide powder had the effect of particle dispersion enhancement on the composite material. Under three-point bending load, C/C-SiC composites show pseudoplastic fracture mode and interlaminar cracking. After 10 h CVI treatment of C/C-SiC composites, the pyrolytic carbon can be used as the interface between carbon fiber and resin carbon matrix. The density and flexural strength of C/C-SiC composites were maximum increased by 4.98% and 38.86%, respectively.
2D laminated carbon cloth as reinforcement, furfurone resin mixed with three inorganic powders such as silicon powder, carbon powder and silicon carbide powder, carbon/carbon-silicon carbide (C/C-SiC) composites were prepared through impregnation, hot-pressing with curing, carbonization and high-temperature heat treatment processes. The effects of addition of silicon powder, carbon powder and silicon carbide powder as well as subsequent chemical vapor infiltration (CVI) treatment on density, microstructure and bending strength of C/C-SiC composites were studied by scanning electron microscope (SEM), multifunctional density , X-ray diffraction (XRD) and universal mechanical testing machine. The results showed that the silicon carbide particles formed by the addition of silicon powder, carbon powder and silicon carbide powder had the effect of particle dispersion enhancement on the composite material. Under three-point bending load, C/C-SiC composites show pseudoplastic fracture mode and interlaminar cracking. After 10 h CVI treatment of C/C-SiC composites, the pyrolytic carbon can be used as the interface between carbon fiber and resin carbon matrix. The density and flexural strength of C/C-SiC composites were maximum increased by 4.98% and 38.86%, respectively.
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doi: 10.1016/S1872-5805(22)60646-2
摘要:
Interfacial adhesion between carbon fiber (CF) and polyetherketoneketone (PEKK) is a key factor that affects the mechanical performances of their composites. Therefore, it is of great importance to impregnate PEKK into CF bundles as efficiently as possible. Here we report that owing to the high dissolubility, PEKK can be introduced onto CF surfaces via a wet strategy. The excellent wettability of PEKK guarantees a full covering and tight binding on CFs, making it possible to evaluate the interfacial shear strength (IFSS) with the microdroplet method. Furthermore, the interior of CF bundles can be completely and uniformly filled with PEKK by the solution impregnation, leading to a high interlaminar shear strength (ILSS). The maximum IFSS and ILSS can reach 107.8 and 99.3 MPa, respectively. Such superior shear properties are ascribed to the formation of amorphous PEKK confined in the limited spacing between CFs.
Interfacial adhesion between carbon fiber (CF) and polyetherketoneketone (PEKK) is a key factor that affects the mechanical performances of their composites. Therefore, it is of great importance to impregnate PEKK into CF bundles as efficiently as possible. Here we report that owing to the high dissolubility, PEKK can be introduced onto CF surfaces via a wet strategy. The excellent wettability of PEKK guarantees a full covering and tight binding on CFs, making it possible to evaluate the interfacial shear strength (IFSS) with the microdroplet method. Furthermore, the interior of CF bundles can be completely and uniformly filled with PEKK by the solution impregnation, leading to a high interlaminar shear strength (ILSS). The maximum IFSS and ILSS can reach 107.8 and 99.3 MPa, respectively. Such superior shear properties are ascribed to the formation of amorphous PEKK confined in the limited spacing between CFs.
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doi: 10.1016/S1872-5805(23)60720-6
摘要:
The interfacial adhesion between carbon fiber (CF) and matrix is crucial to the performance of CF reinforced polymer composites. To evaluate the contribution of mechanical interlocking and chemical anchoring to the interfacial adhesion properties of CF reinforced epoxy resin (EP) composites, the surface roughness and oxygen-containing functional groups of CFs were decoupled to study their effects on interfacial adhesion. The results show that ammonia treatment enhanced the surface roughness with the elemental composition nearly unchanged, while electrochemical treatment enhanced the chemical properties without changing the surface roughness. The interfacial shear strength (IFSS) of CF/EP was tested by the micro-droplet method, and the function relationship between IFSS and surface roughness as well as oxygen content was obtained by linear fitting. The results show that in the T800SC CFs with bifunctional and tetrafunctional epoxy systems, the contribution coefficient of interface adhesion enhancement by chemical anchoring is higher than that by mechanical interlocking.
The interfacial adhesion between carbon fiber (CF) and matrix is crucial to the performance of CF reinforced polymer composites. To evaluate the contribution of mechanical interlocking and chemical anchoring to the interfacial adhesion properties of CF reinforced epoxy resin (EP) composites, the surface roughness and oxygen-containing functional groups of CFs were decoupled to study their effects on interfacial adhesion. The results show that ammonia treatment enhanced the surface roughness with the elemental composition nearly unchanged, while electrochemical treatment enhanced the chemical properties without changing the surface roughness. The interfacial shear strength (IFSS) of CF/EP was tested by the micro-droplet method, and the function relationship between IFSS and surface roughness as well as oxygen content was obtained by linear fitting. The results show that in the T800SC CFs with bifunctional and tetrafunctional epoxy systems, the contribution coefficient of interface adhesion enhancement by chemical anchoring is higher than that by mechanical interlocking.
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doi: 10.1016/S1872-5805(23)60706-1
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The present manuscript reports a coal-based fluorescent CDs which fabricated at room temperature through a friendly method with mixture of hydrogen peroxide (H2O2) and formic acid (HCOOH) as an oxidant instead of concentrated acid (HNO3 or H2SO4). The prepared CDs show the excitation dependent behavior with high QY approximately 7.2%. The as-made CDs are water soluble, robust photo-stability, good resistance to salt solution, insensitive to pH in a range of 2.0-12.0. The coal-based CDs served as a very sensitive nano-probe for the turn-off sensing of Fe3+ ion with a minimum LOD as low as 600 nM in a dynamic range 2 to 100 μM. This efficient, rapid synthesis of coal-based CDs will not only increase high value-added utilization of coal, but also have potential application value in sensing and several another analytical applications.
The present manuscript reports a coal-based fluorescent CDs which fabricated at room temperature through a friendly method with mixture of hydrogen peroxide (H2O2) and formic acid (HCOOH) as an oxidant instead of concentrated acid (HNO3 or H2SO4). The prepared CDs show the excitation dependent behavior with high QY approximately 7.2%. The as-made CDs are water soluble, robust photo-stability, good resistance to salt solution, insensitive to pH in a range of 2.0-12.0. The coal-based CDs served as a very sensitive nano-probe for the turn-off sensing of Fe3+ ion with a minimum LOD as low as 600 nM in a dynamic range 2 to 100 μM. This efficient, rapid synthesis of coal-based CDs will not only increase high value-added utilization of coal, but also have potential application value in sensing and several another analytical applications.
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doi: 10.1016/S1872-5805(22)60643-7
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Polyether ether ketone (PEEK) has favorable mechanical properties. However, its high melt viscosity limits its applications because it is hard to process. In this study, PEEK nanocomposites modified with carbon nanotubes (CNTs) and polyether imide (PEI) were prepared using a direct wet powder blending method. The melt viscosity of the nanocomposites decreased by approximately 50%. Under optimal conditions, the addition of CNTs and PEI resulted in a synergistic increase in the toughness of the nanocomposites. The elongation at break increased by 129%, and the fracture energy increased by 97%. The uniformly dispersed CNTs/PEI powder reduces the processing difficulty of PEEK nanocomposites without affecting the heat resistance. The nanocomposites prepared by this method have lower melt viscosity. This improvement of the properties of PEEK would facilitate its use in the preparation of thermoplastic composites by powder impregnation or laser sintering technology.
Polyether ether ketone (PEEK) has favorable mechanical properties. However, its high melt viscosity limits its applications because it is hard to process. In this study, PEEK nanocomposites modified with carbon nanotubes (CNTs) and polyether imide (PEI) were prepared using a direct wet powder blending method. The melt viscosity of the nanocomposites decreased by approximately 50%. Under optimal conditions, the addition of CNTs and PEI resulted in a synergistic increase in the toughness of the nanocomposites. The elongation at break increased by 129%, and the fracture energy increased by 97%. The uniformly dispersed CNTs/PEI powder reduces the processing difficulty of PEEK nanocomposites without affecting the heat resistance. The nanocomposites prepared by this method have lower melt viscosity. This improvement of the properties of PEEK would facilitate its use in the preparation of thermoplastic composites by powder impregnation or laser sintering technology.
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doi: 10.1016/S1872-5805(22)60597-3
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To obtain excellent carbonaceous precursors, the oxidation reaction mechanism and kinetics of ethylene tar were investigated. The oxidation process of ethylene tar was divided into three stages (350-550 K, 550-700 K and 700-900 K) according to the thermogravimetric curve. To reveal the oxidation reaction mechanism of ethylene tar, the components of evolved gases at different stages were further analyzed online by mass spectrometry and infrared technology. Then, based on the thermogravimetric curve of ethylene tar at different reaction temperatures, the whole reaction process was divided into four parts to perform kinetics simulation calculation. With the help of the iso-conversional method (Coats-Redfern) to analyze the linear regression rates (R2) between 17 common reaction kinetics models and experimental data, the optimal reaction kinetics model for expressing oxidation process of ethylene tar was determined. The results show that: (1) In the oxidation process, the side chains of aromatic compounds firstly react with oxygen to form alcohols and aldehydes, leaving peroxy-radicals to aromatic rings. After that, the aromatic compounds with peroxy-radicals undergo polymerization/condensation reaction to form larger molecular. (2) The fourth-order of reaction model is adopted to describe the first three parts of the oxidation process, and the activation energies are 47.330 kJ·mol−1, 18.689 kJ·mol−1 and 9.004 kJ·mol−1 respectively. The three-dimensional diffusion model is applied to the fourth part of the oxidation process, and the activation energy is 88.369 kJ·mol−1.
To obtain excellent carbonaceous precursors, the oxidation reaction mechanism and kinetics of ethylene tar were investigated. The oxidation process of ethylene tar was divided into three stages (350-550 K, 550-700 K and 700-900 K) according to the thermogravimetric curve. To reveal the oxidation reaction mechanism of ethylene tar, the components of evolved gases at different stages were further analyzed online by mass spectrometry and infrared technology. Then, based on the thermogravimetric curve of ethylene tar at different reaction temperatures, the whole reaction process was divided into four parts to perform kinetics simulation calculation. With the help of the iso-conversional method (Coats-Redfern) to analyze the linear regression rates (R2) between 17 common reaction kinetics models and experimental data, the optimal reaction kinetics model for expressing oxidation process of ethylene tar was determined. The results show that: (1) In the oxidation process, the side chains of aromatic compounds firstly react with oxygen to form alcohols and aldehydes, leaving peroxy-radicals to aromatic rings. After that, the aromatic compounds with peroxy-radicals undergo polymerization/condensation reaction to form larger molecular. (2) The fourth-order of reaction model is adopted to describe the first three parts of the oxidation process, and the activation energies are 47.330 kJ·mol−1, 18.689 kJ·mol−1 and 9.004 kJ·mol−1 respectively. The three-dimensional diffusion model is applied to the fourth part of the oxidation process, and the activation energy is 88.369 kJ·mol−1.
2023, 38(5): 787-803.
doi: 10.1016/S1872-5805(23)60777-2
摘要:
This review provides an extensive analysis of the recycling and regeneration of battery-grade graphite obtained from used lithium-ion batteries. The main objectives are to address supply-demand challenges and minimize environmental pollution. The study focuses on the methods involved in obtaining, separating, purifying, and regenerating spent graphite to ensure its suitability for high-quality energy storage. To improve the graphite recovery efficiency and solve the problem of residual contaminants, techniques like heat treatment, solvent dissolution, and ultrasound treatment are explored. Wet and pyrometallurgical purification and regeneration methods are evaluated, considering their environmental impact and energy consumption. Sustainable and cost-effective approaches, including acid-free purification and low-temperature graphitization, are highlighted. Specific requirements for regenerated graphite in lithium-ion batteries and supercapacitors are discussed, emphasizing customized recycling processes involving acid leaching, high-temperature treatment, and surface coating. Valuable information for the development of efficient and sustainable energy storage systems is provided, addressing environmental issues, and how to meet the increasing demand for graphite anodes.
This review provides an extensive analysis of the recycling and regeneration of battery-grade graphite obtained from used lithium-ion batteries. The main objectives are to address supply-demand challenges and minimize environmental pollution. The study focuses on the methods involved in obtaining, separating, purifying, and regenerating spent graphite to ensure its suitability for high-quality energy storage. To improve the graphite recovery efficiency and solve the problem of residual contaminants, techniques like heat treatment, solvent dissolution, and ultrasound treatment are explored. Wet and pyrometallurgical purification and regeneration methods are evaluated, considering their environmental impact and energy consumption. Sustainable and cost-effective approaches, including acid-free purification and low-temperature graphitization, are highlighted. Specific requirements for regenerated graphite in lithium-ion batteries and supercapacitors are discussed, emphasizing customized recycling processes involving acid leaching, high-temperature treatment, and surface coating. Valuable information for the development of efficient and sustainable energy storage systems is provided, addressing environmental issues, and how to meet the increasing demand for graphite anodes.
2023, 38(5): 804-824.
doi: 10.1016/S1872-5805(23)60774-7
摘要:
As the temperature of electronic devices continues to rise, the quest for high-efficiency heat dissipation has emerged as a critical concern, particularly when it comes to ensuring device performance and longevity. A high thermal conductivity is usually dependent on the ability of fillers to provide thermal conduction channels within composites. In recent years, the development of three-dimensional (3D) interconnected structures using high thermal conductivity fillers in composites has emerged as a promising approach. Compared to the traditional isotropic distribution and directional arrangements, 3D interconnected filler structures improve the thermal conductivity. We review research progress on metal matrix composites with a 3D interconnected carbon filler that have a high thermal conductivity. The thermal conductivity mechanisms and models of composites are elaborated, and important factors relevant to improving the thermal conductivity are considered. Ways of constructing 3D interconnected carbon networks and their effects on the thermal conductivity of their composites should serve as a reference for the advancement of high-performance metal matrix thermal conductivity composites.
As the temperature of electronic devices continues to rise, the quest for high-efficiency heat dissipation has emerged as a critical concern, particularly when it comes to ensuring device performance and longevity. A high thermal conductivity is usually dependent on the ability of fillers to provide thermal conduction channels within composites. In recent years, the development of three-dimensional (3D) interconnected structures using high thermal conductivity fillers in composites has emerged as a promising approach. Compared to the traditional isotropic distribution and directional arrangements, 3D interconnected filler structures improve the thermal conductivity. We review research progress on metal matrix composites with a 3D interconnected carbon filler that have a high thermal conductivity. The thermal conductivity mechanisms and models of composites are elaborated, and important factors relevant to improving the thermal conductivity are considered. Ways of constructing 3D interconnected carbon networks and their effects on the thermal conductivity of their composites should serve as a reference for the advancement of high-performance metal matrix thermal conductivity composites.
2023, 38(5): 825-836.
doi: 10.1016/S1872-5805(23)60749-8
摘要:
Single-wall carbon nanotubes (SWCNTs) have been used to fabricate hydrogen gas (H2) detectors for several decades. It has been proven that they barely interact with H2 so that numerous modifications are used to assist this function. Additives include metals, metal oxides, polymers etc. Previous research suggests that the presence of functional groups on the SWCNTs may improve the response by several orders of magnitude. Recently, many different novel structures have been exploited, and structural parameters of the SWCNTs, such as diameter and chirality, also influence the performance of the detectors. Modifications of the SWCNTs are classified and other factors that influence the performance are also discussed, with the aim of accelerating the manufacture of detectors with a high responsivity and low limit of detection.
Single-wall carbon nanotubes (SWCNTs) have been used to fabricate hydrogen gas (H2) detectors for several decades. It has been proven that they barely interact with H2 so that numerous modifications are used to assist this function. Additives include metals, metal oxides, polymers etc. Previous research suggests that the presence of functional groups on the SWCNTs may improve the response by several orders of magnitude. Recently, many different novel structures have been exploited, and structural parameters of the SWCNTs, such as diameter and chirality, also influence the performance of the detectors. Modifications of the SWCNTs are classified and other factors that influence the performance are also discussed, with the aim of accelerating the manufacture of detectors with a high responsivity and low limit of detection.
2023, 38(5): 837-860.
doi: 10.1016/S1872-5805(23)60779-6
摘要:
Capacitive deionization (CDI) is a potential cost-efficient desalination technology. Its performance is intrinsically limited by the structure and properties of the electrode materials. Biomass materials have become a research hotspot for CDI electrode materials because of their abundance, low cost, and unique structure. The preparation, desalination performance, and regeneration status of biochar electrodes are summarized and clarified. Their preparation and use in CDI in recent years are presented and compared, and the effects of biochar electrode materials and CDI operating parameters on the desalination performance are emphasized. It is found that the salt adsorption capacity is positively correlated with the percent mesoporous material they contain. The selective adsorption of ions mainly depends on ion properties like ionic radius and charge as well as voltage, charging time and feed water characteristics. The current status and methods of electrode regeneration are discussed and future developments are suggested.
Capacitive deionization (CDI) is a potential cost-efficient desalination technology. Its performance is intrinsically limited by the structure and properties of the electrode materials. Biomass materials have become a research hotspot for CDI electrode materials because of their abundance, low cost, and unique structure. The preparation, desalination performance, and regeneration status of biochar electrodes are summarized and clarified. Their preparation and use in CDI in recent years are presented and compared, and the effects of biochar electrode materials and CDI operating parameters on the desalination performance are emphasized. It is found that the salt adsorption capacity is positively correlated with the percent mesoporous material they contain. The selective adsorption of ions mainly depends on ion properties like ionic radius and charge as well as voltage, charging time and feed water characteristics. The current status and methods of electrode regeneration are discussed and future developments are suggested.
2023, 38(5): 861-874.
doi: 10.1016/S1872-5805(23)60776-0
摘要:
Zeolite-templated carbons (ZTCs) have a unique three-dimensional (3D) ordered microporous structure and an extra-large surface area, and have excellent properties in adsorption and energy storage. Unfortunately, the lack of efficient synthesis strategies and the difficulty of doing this on a large-scale have seriously limited their development. We have developed a large-scale simple production route using a relatively low synthesis temperature and direct acetylene chemical vapor deposition (CVD) using Co ion-exchanged zeolite Y (CoY) as the template. The Co2+ confined in the zeolite acts as Lewis acid sites to catalyze the pyrolysis of acetylene through the d-π coordination effect, making carbon deposition occur selectively inside the zeolite at 400 °C rather than on the external surface. By systematically investigating the CVD temperature and time, the optimum conditions of 8 h deposition at 400 °C produces an excellent 3D ordered-microporous structure and outstanding structure parameters (3 000 m2 g−1, 1.33 cm3 g−1). Its CO2 adsorption capacity and selectivity are 2.78 mmol g−1 (25 °C, 100 kPa) and 98, respectively. This simple CVD process allows the synthesis of high-quality ZTCs on a large scale at a low cost.
Zeolite-templated carbons (ZTCs) have a unique three-dimensional (3D) ordered microporous structure and an extra-large surface area, and have excellent properties in adsorption and energy storage. Unfortunately, the lack of efficient synthesis strategies and the difficulty of doing this on a large-scale have seriously limited their development. We have developed a large-scale simple production route using a relatively low synthesis temperature and direct acetylene chemical vapor deposition (CVD) using Co ion-exchanged zeolite Y (CoY) as the template. The Co2+ confined in the zeolite acts as Lewis acid sites to catalyze the pyrolysis of acetylene through the d-π coordination effect, making carbon deposition occur selectively inside the zeolite at 400 °C rather than on the external surface. By systematically investigating the CVD temperature and time, the optimum conditions of 8 h deposition at 400 °C produces an excellent 3D ordered-microporous structure and outstanding structure parameters (3 000 m2 g−1, 1.33 cm3 g−1). Its CO2 adsorption capacity and selectivity are 2.78 mmol g−1 (25 °C, 100 kPa) and 98, respectively. This simple CVD process allows the synthesis of high-quality ZTCs on a large scale at a low cost.
2023, 38(5): 875-886.
doi: 10.1016/S1872-5805(23)60770-X
摘要:
为解决电磁辐射污染问题，开发经济环保的高效电磁波吸收材料制备工艺刻不容缓。碳基电磁波吸收材料因其独特优势而备受关注，但合适的前驱体碳源以及合理孔结构构筑策略仍是其制备面临的难题。本文以资源丰富的煤液化油渣为碳源，通过盐模板辅助策略，利用NaHCO3模板热分解过程中产生的Na2CO3和大量气体实现了多孔炭骨架的定向形成。相互贯穿的多孔结构不仅调节了炭材料的阻抗匹配，还延长了电磁波的传输路径，增强了介电损耗，在多种电磁损耗机制的协同作用下，煤液化残渣基多孔炭材料展现出优异的电磁波吸收能力。在质量分数仅为10%的填充比以及2.03 mm的厚度下，获得的多孔炭材料展现出−60.28 dB的反射损耗值，并实现了5.36 GHz的有效吸收频宽。因此，本文为高性能碳基电磁波吸收材料的开发提供了新的途径，也为煤液化油渣产品的高附加值利用提供了新的思路。
为解决电磁辐射污染问题，开发经济环保的高效电磁波吸收材料制备工艺刻不容缓。碳基电磁波吸收材料因其独特优势而备受关注，但合适的前驱体碳源以及合理孔结构构筑策略仍是其制备面临的难题。本文以资源丰富的煤液化油渣为碳源，通过盐模板辅助策略，利用NaHCO3模板热分解过程中产生的Na2CO3和大量气体实现了多孔炭骨架的定向形成。相互贯穿的多孔结构不仅调节了炭材料的阻抗匹配，还延长了电磁波的传输路径，增强了介电损耗，在多种电磁损耗机制的协同作用下，煤液化残渣基多孔炭材料展现出优异的电磁波吸收能力。在质量分数仅为10%的填充比以及2.03 mm的厚度下，获得的多孔炭材料展现出−60.28 dB的反射损耗值，并实现了5.36 GHz的有效吸收频宽。因此，本文为高性能碳基电磁波吸收材料的开发提供了新的途径，也为煤液化油渣产品的高附加值利用提供了新的思路。
2023, 38(5): 887-897.
doi: 10.1016/S1872-5805(23)60775-9
摘要:
Vertically aligned carbon nanotube (VACNT) arrays with good mechanical properties and high thermal conductivity can be used as effective thermal interface materials in thermal management. In order to take advantage of the high thermal conductivity along the axis of nanotubes, the quality and height of the arrays need to be optimized. However, the immense synthesis parameter space for VACNT arrays and the interdependence of structural features make it challenging to improve both their height and quality. We have developed a literature mining approach combined with machine learning and high-throughput design to efficiently optimize the height and quality of the arrays. To reveal the underlying relationship between VACNT structures and their key growth parameters, we used random forest regression (RFR) and SHapley Additive exPlanation (SHAP) methods to model a set of published sample data (864 samples). High-throughput experiments were designed to change 4 key parameters: growth temperature, growth time, catalyst composition, and concentration of the carbon source. It was found that a screened Fe/Gd/Al2O3 catalyst was able to grow VACNT arrays with millimeter-scale height and improved quality. Our results demonstrate that this approach can effectively deal with multi-parameter processes such as nanotube growth and improve control over their structures.
Vertically aligned carbon nanotube (VACNT) arrays with good mechanical properties and high thermal conductivity can be used as effective thermal interface materials in thermal management. In order to take advantage of the high thermal conductivity along the axis of nanotubes, the quality and height of the arrays need to be optimized. However, the immense synthesis parameter space for VACNT arrays and the interdependence of structural features make it challenging to improve both their height and quality. We have developed a literature mining approach combined with machine learning and high-throughput design to efficiently optimize the height and quality of the arrays. To reveal the underlying relationship between VACNT structures and their key growth parameters, we used random forest regression (RFR) and SHapley Additive exPlanation (SHAP) methods to model a set of published sample data (864 samples). High-throughput experiments were designed to change 4 key parameters: growth temperature, growth time, catalyst composition, and concentration of the carbon source. It was found that a screened Fe/Gd/Al2O3 catalyst was able to grow VACNT arrays with millimeter-scale height and improved quality. Our results demonstrate that this approach can effectively deal with multi-parameter processes such as nanotube growth and improve control over their structures.
2023, 38(5): 898-912.
doi: 10.1016/S1872-5805(23)60760-7
摘要:
Two-dimensional (2D) carbon materials have attracted enormous attention, but the complicated synthesis methods, inhomogeneous structure and uncontrollable properties still limit their use. Here we report a universal protocol for fabricating a series of heteroatom-doped 2D porous polymers, including pyrrole and indole as nitrogen-dopant sources, and 3,4-ethoxylene dioxy thiophene as a sulfur-dopant source by a simple chemical crosslinking reaction. This bottom-up strategy allows for the large-scale synthesis of functionalized ultrathin carbon nanosheets with a high heteroatom doping content and abundant porosity. Consequently, the obtained N-doped carbon-rich nanosheets (NCNs) sample has a specific capacity of 573.4 mAh g−1 at 5 A g−1 as an anode for lithium-ion capacitors (LICs), and the optimized sample has a specific capacitance of 100.0 F g−1 at 5 A g−1 when used as a cathode for a LIC. A dual-carbon LIC device was also developed that had an energy density of 168.4 Wh kg−1 at 400 W kg−1, while maintaining outstanding cycling stability with a retention rate of 86.3% after 10 000 cycles. This approach has the potential to establish a way for the precise synthesis of substantial amounts of 2D functionalized carbon nanosheets with the desired structure and properties.
Two-dimensional (2D) carbon materials have attracted enormous attention, but the complicated synthesis methods, inhomogeneous structure and uncontrollable properties still limit their use. Here we report a universal protocol for fabricating a series of heteroatom-doped 2D porous polymers, including pyrrole and indole as nitrogen-dopant sources, and 3,4-ethoxylene dioxy thiophene as a sulfur-dopant source by a simple chemical crosslinking reaction. This bottom-up strategy allows for the large-scale synthesis of functionalized ultrathin carbon nanosheets with a high heteroatom doping content and abundant porosity. Consequently, the obtained N-doped carbon-rich nanosheets (NCNs) sample has a specific capacity of 573.4 mAh g−1 at 5 A g−1 as an anode for lithium-ion capacitors (LICs), and the optimized sample has a specific capacitance of 100.0 F g−1 at 5 A g−1 when used as a cathode for a LIC. A dual-carbon LIC device was also developed that had an energy density of 168.4 Wh kg−1 at 400 W kg−1, while maintaining outstanding cycling stability with a retention rate of 86.3% after 10 000 cycles. This approach has the potential to establish a way for the precise synthesis of substantial amounts of 2D functionalized carbon nanosheets with the desired structure and properties.
2023, 38(5): 913-924.
doi: 10.1016/S1872-5805(23)60769-3
摘要:
The rapid development of flexible supercapacitors has been impeded by the difficulty of preparing flexible electrodes. We report the fabrication of a highly flexible and conductive microporous graphene-based substrate obtained by direct laser writing combined with KOH activation, which we call activated laser-produced graphene (a-LPG), which is then decorated with electrochemically deposited MnO2 to form a flexible a-LIG/MnO2 thin-film electrode. This hybrid electrode has a high areal capacitance of 304.61 mF/cm2 at a current density of 1 mA/cm2 in a 1 mol/L Na2SO4 aqueous electrolyte. A flexible asymmetric supercapacitor with a-LIG/MnO2 as the anode, a-LIG as the cathode and PVA/ H3PO4 as a gel electrolyte was assembled, giving an areal energy density of 2.61 μWh/cm2 at a power density of 260.28 µW/cm2 and an ultra-high areal capacitance of 18.82 mF/cm2 at 0.2 mA/cm2, with 90.28% capacitance retained after 5 000 cycles. It also has an excellent electrochemical performance even in the bent state. This work provides an easy and scalable method to design high-performance flexible supercapacitor electrodes and may open a new way for their large-scale fabrication.
The rapid development of flexible supercapacitors has been impeded by the difficulty of preparing flexible electrodes. We report the fabrication of a highly flexible and conductive microporous graphene-based substrate obtained by direct laser writing combined with KOH activation, which we call activated laser-produced graphene (a-LPG), which is then decorated with electrochemically deposited MnO2 to form a flexible a-LIG/MnO2 thin-film electrode. This hybrid electrode has a high areal capacitance of 304.61 mF/cm2 at a current density of 1 mA/cm2 in a 1 mol/L Na2SO4 aqueous electrolyte. A flexible asymmetric supercapacitor with a-LIG/MnO2 as the anode, a-LIG as the cathode and PVA/ H3PO4 as a gel electrolyte was assembled, giving an areal energy density of 2.61 μWh/cm2 at a power density of 260.28 µW/cm2 and an ultra-high areal capacitance of 18.82 mF/cm2 at 0.2 mA/cm2, with 90.28% capacitance retained after 5 000 cycles. It also has an excellent electrochemical performance even in the bent state. This work provides an easy and scalable method to design high-performance flexible supercapacitor electrodes and may open a new way for their large-scale fabrication.
2023, 38(5): 925-938.
doi: 10.1016/S1872-5805(23)60778-4
摘要:
Recently, solar-driven interfacial water evaporation (SDIWE) has attracted worldwide attention owing to its potential use in seawater desalination and wastewater purification. Nevertheless, how to effectively use the inevitable conduction heat loss and eliminate organic pollutants are still challenging. We report the SDIWE- assisted adsorption of organic pollutants by using the conduction heat loss to improve the total energy efficiency of the SDIWE system. Porous carbon (PC) and activated PC were prepared by a simple recrystallizing salt template-assisted carbonization and KOH activation method. After activation, the activated PC sample with a PC:KOH mass ratio of 1:4 (PC-A4) has a hierarchical porous structure, a better absorption capacity in the spectral region of 200-2500 nm, a high specific surface area of 1867.71 m2 g−1 and a large pore volume of 1.04 cm3 g−1. Based on this, PC-A4 has a high evaporation rate and energy efficiency, which can be further increased by regulating the mass of the water body. Subsequently, the conduction heat generated by the SDIWE system was used for SDIWE-assisted adsorption. Notably, the maximum amount of rhodamine B adsorbed by PC-A4 is 1610 mg g−1 at a conduction temperature of 309 K, which is higher than that of the same sample at 298 K. Consequently, this work offers a promising approach for effectively using the conduction heat loss of the SDIWE system and developing it for water purification.
Recently, solar-driven interfacial water evaporation (SDIWE) has attracted worldwide attention owing to its potential use in seawater desalination and wastewater purification. Nevertheless, how to effectively use the inevitable conduction heat loss and eliminate organic pollutants are still challenging. We report the SDIWE- assisted adsorption of organic pollutants by using the conduction heat loss to improve the total energy efficiency of the SDIWE system. Porous carbon (PC) and activated PC were prepared by a simple recrystallizing salt template-assisted carbonization and KOH activation method. After activation, the activated PC sample with a PC:KOH mass ratio of 1:4 (PC-A4) has a hierarchical porous structure, a better absorption capacity in the spectral region of 200-2500 nm, a high specific surface area of 1867.71 m2 g−1 and a large pore volume of 1.04 cm3 g−1. Based on this, PC-A4 has a high evaporation rate and energy efficiency, which can be further increased by regulating the mass of the water body. Subsequently, the conduction heat generated by the SDIWE system was used for SDIWE-assisted adsorption. Notably, the maximum amount of rhodamine B adsorbed by PC-A4 is 1610 mg g−1 at a conduction temperature of 309 K, which is higher than that of the same sample at 298 K. Consequently, this work offers a promising approach for effectively using the conduction heat loss of the SDIWE system and developing it for water purification.
2023, 38(5): 939-953.
doi: 10.1016/S1872-5805(23)60759-0
摘要:
Despite recent interest in the low-temperature carbonization of coal to prepare disordered carbon materials for the anodes of lithium-ion (LIBs) and sodium-ion batteries (SIBs), the carbonization mechanism is still poorly understood. We selected bituminous coal as the raw material and investigated the chemical, microcrystal, and pore structure changes during the carbonization process from coal to the resulting disordered carbon. These structural changes with temperature below 1 000 °C show an increase in both interlayer spacing (3.69–3.82 Å) and defect concentration (1.26–1.90), accompanied by the generation of a large amount of nano-microporous materials. These changes are attributed to the migration of the local carbon layer and the release of small molecules. Furthermore, a decrease in interlayer spacing and defect concentration occurs between 1 000 °C and 1 600 °C. In LIBs, samples carbonized at 1000 °C showed the best electrochemical performance, with a reversible capacity of 384 mAh g−1 at 0.1 C and excellent rate performance, maintaining 170 mAh g−1 at 5 C. In SIBs, samples carbonized at 1 200 °C had a reversible capacity of 270.1 mAh g−1 at 0.1 C and a high initial Coulombic efficiency of 86.8%. This study offers theoretical support for refining the preparation of carbon materials derived from coal.
Despite recent interest in the low-temperature carbonization of coal to prepare disordered carbon materials for the anodes of lithium-ion (LIBs) and sodium-ion batteries (SIBs), the carbonization mechanism is still poorly understood. We selected bituminous coal as the raw material and investigated the chemical, microcrystal, and pore structure changes during the carbonization process from coal to the resulting disordered carbon. These structural changes with temperature below 1 000 °C show an increase in both interlayer spacing (3.69–3.82 Å) and defect concentration (1.26–1.90), accompanied by the generation of a large amount of nano-microporous materials. These changes are attributed to the migration of the local carbon layer and the release of small molecules. Furthermore, a decrease in interlayer spacing and defect concentration occurs between 1 000 °C and 1 600 °C. In LIBs, samples carbonized at 1000 °C showed the best electrochemical performance, with a reversible capacity of 384 mAh g−1 at 0.1 C and excellent rate performance, maintaining 170 mAh g−1 at 5 C. In SIBs, samples carbonized at 1 200 °C had a reversible capacity of 270.1 mAh g−1 at 0.1 C and a high initial Coulombic efficiency of 86.8%. This study offers theoretical support for refining the preparation of carbon materials derived from coal.
2023, 38(5): 954-963.
doi: 10.1016/S1872-5805(23)60749-8
摘要:
A variety of industrial preparation methods to obtain graphene from graphite have been developed, the most prominent of which are the chemical reduction of graphene oxide and intercalation-exfoliation methods. However, the low-cost, thin-layer, large-scale production of graphene with a radial dimension smaller than 1 μm (SG) remains a great challenge, which has limited the industrial development and application of small-scale graphene in areas such as textile fibers, engine oil additives, and graphene-polymer composites. We have developed a novel way to solve this problem by improved ball milling methods which form molecular-scale grinding aids between the graphite layers. This method can produce uniform, small-size (less than 1 μm) and thin-layer graphene nanosheets at a low cost, while ensuring minimal damage to the internal graphene structure. We also show that using this SG as an additive in lubricating oil not only solves the current dispersion stability of graphene, but also reduces the friction coefficient by more than 27% and wear by more than 38.8%. The SG preparation method reported is simple, low-cost, and has a significant effect in lubricating applications, which is of great commercial value.
A variety of industrial preparation methods to obtain graphene from graphite have been developed, the most prominent of which are the chemical reduction of graphene oxide and intercalation-exfoliation methods. However, the low-cost, thin-layer, large-scale production of graphene with a radial dimension smaller than 1 μm (SG) remains a great challenge, which has limited the industrial development and application of small-scale graphene in areas such as textile fibers, engine oil additives, and graphene-polymer composites. We have developed a novel way to solve this problem by improved ball milling methods which form molecular-scale grinding aids between the graphite layers. This method can produce uniform, small-size (less than 1 μm) and thin-layer graphene nanosheets at a low cost, while ensuring minimal damage to the internal graphene structure. We also show that using this SG as an additive in lubricating oil not only solves the current dispersion stability of graphene, but also reduces the friction coefficient by more than 27% and wear by more than 38.8%. The SG preparation method reported is simple, low-cost, and has a significant effect in lubricating applications, which is of great commercial value.
2023, 38(5): 964-975.
doi: 10.1016/S1872-5805(23)60707-3
摘要:
Phenolic resin was coated on the surface of nano-Si by a microencapsulation technique, and then carbonized under Ar protection to prepare a nano-Si/C composite. The composites were first prepared using 4 different mass ratios (1∶2, 1∶4, 1∶6, 1∶8) of phenolic resin to nano-Si. The obtained average thicknesses of amorphous carbon coating were 7, 4.5, 3.7, 2.8 nm, respectively. By comparing the cycling and rate capability, the best electrochemical performance was obtained when this ratio was 1∶4, with a 4.5 nm amorphous carbon coating. The electrochemical properties of this material were then comprehensively evaluated, showing excellent electrochemical performance as an anode material for Li-ion batteries. At a current density of 100 mAg−1, the material had a first specific discharge capacity of 2 382 mAhg−1, a first charge specific capacity of 1 667 mAhg−1, and an initial coulombic efficiency of 70%. A discharge specific capacity of 835.6 mAhg−1 was retained after 200 cycles with a high coulombic efficiency of 99.2%. In addition, the nano-Si/C composite demonstrated superior rate performance. Under current densities of 100, 200, 500, 1 000 and 2 000 mAg−1, the average specific discharge capacities were 1 716.4, 1 231.6, 911.7, 676.1 and 339.8 mAh g−1, respectively. When the current density returned to 100 mA g−1, the specific capacity returned to 1 326.4 mAh g−1.
Phenolic resin was coated on the surface of nano-Si by a microencapsulation technique, and then carbonized under Ar protection to prepare a nano-Si/C composite. The composites were first prepared using 4 different mass ratios (1∶2, 1∶4, 1∶6, 1∶8) of phenolic resin to nano-Si. The obtained average thicknesses of amorphous carbon coating were 7, 4.5, 3.7, 2.8 nm, respectively. By comparing the cycling and rate capability, the best electrochemical performance was obtained when this ratio was 1∶4, with a 4.5 nm amorphous carbon coating. The electrochemical properties of this material were then comprehensively evaluated, showing excellent electrochemical performance as an anode material for Li-ion batteries. At a current density of 100 mAg−1, the material had a first specific discharge capacity of 2 382 mAhg−1, a first charge specific capacity of 1 667 mAhg−1, and an initial coulombic efficiency of 70%. A discharge specific capacity of 835.6 mAhg−1 was retained after 200 cycles with a high coulombic efficiency of 99.2%. In addition, the nano-Si/C composite demonstrated superior rate performance. Under current densities of 100, 200, 500, 1 000 and 2 000 mAg−1, the average specific discharge capacities were 1 716.4, 1 231.6, 911.7, 676.1 and 339.8 mAh g−1, respectively. When the current density returned to 100 mA g−1, the specific capacity returned to 1 326.4 mAh g−1.
2023, 38(5): 976-988.
doi: 10.1016/S1872-5805(23)60735-8
摘要:
Developing low-cost, highly-efficient and stable catalysts for the oxygen reduction reaction (ORR) of fuel cells is highly desirable yet challenging. We have developed a Co―N―C ORR catalyst with an intact hollow spherical structure and a large surface area which has been systematically characterized. It was produced by the uniform growth of zeolitic imidazolate frameworks (ZIF s) on the surface of nano-polystyrene (PS) spheres followed by their decomposition. Notably, the as-prepared catalyst Co-NHCP-2 (2 represents a mass ratio of 0.6 between Zn(NO3)2·6H2O and 2-methylimidazole has a porous structure, a super large specific surface area (1817.24 m2 g−1), high contents of pyridinic-N, pyrrolic-N, and graphitic-N, and a uniform Co distribution. As an efficient electrocatalyst, it shows promise in terms of a high onset potential (Eonset) of 0.96 V, a high half-wave potential (E1/2) of 0.84 V, and a limited current density of 5.50 mA cm−2. The catalyst has a nearly 4e pathway for the ORR in an alkaline solution as well as stronger methanol tolerance and higher long-term durability than commercially available Pt/C catalysts. These results show that the obtained material may be a promising electrocatalyst for the ORR.
Developing low-cost, highly-efficient and stable catalysts for the oxygen reduction reaction (ORR) of fuel cells is highly desirable yet challenging. We have developed a Co―N―C ORR catalyst with an intact hollow spherical structure and a large surface area which has been systematically characterized. It was produced by the uniform growth of zeolitic imidazolate frameworks (ZIF s) on the surface of nano-polystyrene (PS) spheres followed by their decomposition. Notably, the as-prepared catalyst Co-NHCP-2 (2 represents a mass ratio of 0.6 between Zn(NO3)2·6H2O and 2-methylimidazole has a porous structure, a super large specific surface area (1817.24 m2 g−1), high contents of pyridinic-N, pyrrolic-N, and graphitic-N, and a uniform Co distribution. As an efficient electrocatalyst, it shows promise in terms of a high onset potential (Eonset) of 0.96 V, a high half-wave potential (E1/2) of 0.84 V, and a limited current density of 5.50 mA cm−2. The catalyst has a nearly 4e pathway for the ORR in an alkaline solution as well as stronger methanol tolerance and higher long-term durability than commercially available Pt/C catalysts. These results show that the obtained material may be a promising electrocatalyst for the ORR.
2023, 38(5): 989-996.
doi: 10.1016/S1872-5805(23)60728-0
摘要:
The surface of carbon fibers (CFs) was modified by a surfactant (ferrocenemethyl)dodecyldimethylammonium bromide (FDDA) to enhance the interfacial ashesion between the CFs and surrounding matrix. Results showed that it could be electrochemically desorbed by a potentiostatic electro-oxidation method. The FDDA adsorption isotherm was attributed to the formation of multi-molecular layers mainly by non-electrostatic interactions. The adsorption and desorption of FDDA on the CFs have little effect on their tensile strength. The effects of FDDA modification on the interfacial properties of CF/epoxy composites were evaluated by a single-filament fragmentation test. Compared with the un-modified CFs, the FDDA-modified ones had significantly improved interfacial adhesion properties in the composites. This method provides a potential approach for preparing recyclable CF/resin composites.
The surface of carbon fibers (CFs) was modified by a surfactant (ferrocenemethyl)dodecyldimethylammonium bromide (FDDA) to enhance the interfacial ashesion between the CFs and surrounding matrix. Results showed that it could be electrochemically desorbed by a potentiostatic electro-oxidation method. The FDDA adsorption isotherm was attributed to the formation of multi-molecular layers mainly by non-electrostatic interactions. The adsorption and desorption of FDDA on the CFs have little effect on their tensile strength. The effects of FDDA modification on the interfacial properties of CF/epoxy composites were evaluated by a single-filament fragmentation test. Compared with the un-modified CFs, the FDDA-modified ones had significantly improved interfacial adhesion properties in the composites. This method provides a potential approach for preparing recyclable CF/resin composites.
摘要：
超级电容器具有高功率密度、长循环寿命、良好的低温使用性能和安全性的优点，已经广泛应用到电子产品、能量回收和储能等领域。电极材料和电解液是决定超级电容器性能的两大关键因素，超级电容器常用的电极材料包括碳质材料（活性炭、碳纳米管、石墨烯、炭纤维、纳米洋葱碳等）、金属氧化物（金属氢氧化物）、导电聚合物及复合材料等；电解液主要有水系电解液、有机系电解液与离子液体。本文综述了超级电容器电极材料与电解液的研究现状，详细介绍了电极材料、电解液的性能及优缺点，并对新型电极材料和电解液的研究趋势提出展望。
超级电容器具有高功率密度、长循环寿命、良好的低温使用性能和安全性的优点，已经广泛应用到电子产品、能量回收和储能等领域。电极材料和电解液是决定超级电容器性能的两大关键因素，超级电容器常用的电极材料包括碳质材料（活性炭、碳纳米管、石墨烯、炭纤维、纳米洋葱碳等）、金属氧化物（金属氢氧化物）、导电聚合物及复合材料等；电解液主要有水系电解液、有机系电解液与离子液体。本文综述了超级电容器电极材料与电解液的研究现状，详细介绍了电极材料、电解液的性能及优缺点，并对新型电极材料和电解液的研究趋势提出展望。
摘要：
研究了不同掺量下氧化石墨烯(GO)对水泥石以及胶砂微观结构和力学性能的影响。含16.5%水的水泥浆、0.05%GO及3倍于水泥的沙子共混物作为添加剂制备成砂浆。通过SEM、液氮吸附仪和一系列标准实验分别对水泥石的微观形态、孔隙结构、抗压抗折强度以及水泥净浆的流动度、黏度、凝结时间进行表征;考察不同GO掺量下水泥水化放热的变化情况。结果表明:GO对水泥浆有显著增稠和促凝作用;GO的掺入可以有效降低水泥的水化放热量;GO对水泥石有显著的增强增韧效果,28天龄期时,GO质量分数为0.05%的水泥石,3、7和28 d抗压强度和抗折强度同比对照组分别增加52.4%、46.5%、40.4%和86.1%、68.5%、90.5%,胶砂的抗压强度和抗折强度同比对照组分别增加43.2%、33%、24.4%和69.4%、106.4%、70.5%;GO在水泥硬化过程中对水泥石中晶体产物的产生有促进作用并能规整晶体的排布而形成针状晶体簇,改善水泥石中的孔结构,降低水泥石中微孔的体积,增加水泥石的密实度,对水泥石有显著地增强增韧效果。
研究了不同掺量下氧化石墨烯(GO)对水泥石以及胶砂微观结构和力学性能的影响。含16.5%水的水泥浆、0.05%GO及3倍于水泥的沙子共混物作为添加剂制备成砂浆。通过SEM、液氮吸附仪和一系列标准实验分别对水泥石的微观形态、孔隙结构、抗压抗折强度以及水泥净浆的流动度、黏度、凝结时间进行表征;考察不同GO掺量下水泥水化放热的变化情况。结果表明:GO对水泥浆有显著增稠和促凝作用;GO的掺入可以有效降低水泥的水化放热量;GO对水泥石有显著的增强增韧效果,28天龄期时,GO质量分数为0.05%的水泥石,3、7和28 d抗压强度和抗折强度同比对照组分别增加52.4%、46.5%、40.4%和86.1%、68.5%、90.5%,胶砂的抗压强度和抗折强度同比对照组分别增加43.2%、33%、24.4%和69.4%、106.4%、70.5%;GO在水泥硬化过程中对水泥石中晶体产物的产生有促进作用并能规整晶体的排布而形成针状晶体簇,改善水泥石中的孔结构,降低水泥石中微孔的体积,增加水泥石的密实度,对水泥石有显著地增强增韧效果。
摘要：
磷酸活化法是植物纤维原料制备活性炭的主要化学活化方法。笔者系统综述了磷酸活化过程中活性炭孔隙结构的调控机制。从化学的观点，笔者提出植物纤维原料的磷酸活化在本质上是磷酸-生物高分子复合体的形成与热处理两个过程。基于这一概念，分析了植物纤维原料的组成与结构、浸渍条件等因素对磷酸-生物高分子复合体的组成与结构的影响，全面总结了植物纤维原料种类与预处理、植物细胞壁结构和结晶度、浸渍比、浸渍方式、温度和时间等组成、结构与条件对磷酸法活性炭孔隙结构的形成与发展的影响规律。在磷酸-生物高分子热处理过程中，系统总结了炭化温度、升温速率与中间停留温度等加热历程、惰性气体、氧化性气体和水蒸气等气氛对磷酸活化法活性炭孔隙结构的影响规律。最后概述了氧化性气氛和氧化试剂对磷酸活化过程的影响机理，以及磷酸活化过程中固相炭化和气相炭化对活性炭孔隙结构发展的贡献。
磷酸活化法是植物纤维原料制备活性炭的主要化学活化方法。笔者系统综述了磷酸活化过程中活性炭孔隙结构的调控机制。从化学的观点，笔者提出植物纤维原料的磷酸活化在本质上是磷酸-生物高分子复合体的形成与热处理两个过程。基于这一概念，分析了植物纤维原料的组成与结构、浸渍条件等因素对磷酸-生物高分子复合体的组成与结构的影响，全面总结了植物纤维原料种类与预处理、植物细胞壁结构和结晶度、浸渍比、浸渍方式、温度和时间等组成、结构与条件对磷酸法活性炭孔隙结构的形成与发展的影响规律。在磷酸-生物高分子热处理过程中，系统总结了炭化温度、升温速率与中间停留温度等加热历程、惰性气体、氧化性气体和水蒸气等气氛对磷酸活化法活性炭孔隙结构的影响规律。最后概述了氧化性气氛和氧化试剂对磷酸活化过程的影响机理，以及磷酸活化过程中固相炭化和气相炭化对活性炭孔隙结构发展的贡献。
摘要：
C/C复合材料因优异的高温性能被认为是高温结构件的理想材料。然而,C/C复合材料在高温高速粒子冲刷环境下的氧化烧蚀问题严重制约其应用。因此,如何提高C/C复合材料的抗烧蚀性能显得尤为重要。笔者综述C/C复合材料抗烧蚀的研究现状。目前,提高C/C复合材料抗烧蚀性能的途径主要集中于优化炭纤维预制体结构、控制热解炭织构、基体中陶瓷掺杂改性和表面涂覆抗烧蚀涂层等4种方法。主要介绍以上4种方法的研究现状,重点介绍基体改性和抗烧蚀涂层的最新研究进展。其中,涂层和基体改性是提高C/C复合材料抗烧蚀性能的两种有效方法。未来C/C 复合材料抗烧蚀研究的潜在方向主要集中于降低制造成本、控制热解炭织构、优化掺杂的陶瓷相以及将基体改性和涂层技术相结合。
C/C复合材料因优异的高温性能被认为是高温结构件的理想材料。然而,C/C复合材料在高温高速粒子冲刷环境下的氧化烧蚀问题严重制约其应用。因此,如何提高C/C复合材料的抗烧蚀性能显得尤为重要。笔者综述C/C复合材料抗烧蚀的研究现状。目前,提高C/C复合材料抗烧蚀性能的途径主要集中于优化炭纤维预制体结构、控制热解炭织构、基体中陶瓷掺杂改性和表面涂覆抗烧蚀涂层等4种方法。主要介绍以上4种方法的研究现状,重点介绍基体改性和抗烧蚀涂层的最新研究进展。其中,涂层和基体改性是提高C/C复合材料抗烧蚀性能的两种有效方法。未来C/C 复合材料抗烧蚀研究的潜在方向主要集中于降低制造成本、控制热解炭织构、优化掺杂的陶瓷相以及将基体改性和涂层技术相结合。
摘要：
评价了中国40多年来在航天、航空、光伏、粉末冶金、工业高温炉领域成功应用的针刺C/C,正交3D C/C、径编C/C、穿刺C/C、轴编C/C等五类C/C复合材料的物理、力学、热学、烧蚀、摩擦磨损、使用寿命等性能及特点,并与其他国家相应材料性能进行分析对比,为建立工程应用C/C复合材料共享的数据库平台奠定基础。揭示了炭纤维预制体、炭基体类型、界面结合状态与材料性能的关联度。指出炭纤维预制体结构单元精细化研究和其结构的梯度设计,以及炭基体的优化组合匹配技术,仍是C/C复合材料性能稳定化提升的重点研究方向。
评价了中国40多年来在航天、航空、光伏、粉末冶金、工业高温炉领域成功应用的针刺C/C,正交3D C/C、径编C/C、穿刺C/C、轴编C/C等五类C/C复合材料的物理、力学、热学、烧蚀、摩擦磨损、使用寿命等性能及特点,并与其他国家相应材料性能进行分析对比,为建立工程应用C/C复合材料共享的数据库平台奠定基础。揭示了炭纤维预制体、炭基体类型、界面结合状态与材料性能的关联度。指出炭纤维预制体结构单元精细化研究和其结构的梯度设计,以及炭基体的优化组合匹配技术,仍是C/C复合材料性能稳定化提升的重点研究方向。
摘要：
利用化学氧化还原法制备出石墨烯。通过原位聚合法及溶液混合法制备出石墨烯/聚酰亚胺复合材料,考察不同复合材料制备方法对其机械性能及导电性能的影响,并对其作用机理进行探讨。结果表明,制备的石墨烯为二维的单层或寡层材料,加入到聚酰亚胺中能够增强其机械性能及电导率。相比溶液混合法,采用原位聚合法时石墨烯在聚酰亚胺基体中分散更均匀,对其团聚作用有更好的抑制作用,制备的复合材料性能更优异。采用该法加入石墨烯的量为1.0 wt%时,拉伸强度达到了132.5 MPa,提高了68.8%;加入量增加到3.0 wt%时,电导率达6.87×10-4S·m-1,提高了8个数量级,对聚酰亚胺的性能有显著的增强作用。
利用化学氧化还原法制备出石墨烯。通过原位聚合法及溶液混合法制备出石墨烯/聚酰亚胺复合材料,考察不同复合材料制备方法对其机械性能及导电性能的影响,并对其作用机理进行探讨。结果表明,制备的石墨烯为二维的单层或寡层材料,加入到聚酰亚胺中能够增强其机械性能及电导率。相比溶液混合法,采用原位聚合法时石墨烯在聚酰亚胺基体中分散更均匀,对其团聚作用有更好的抑制作用,制备的复合材料性能更优异。采用该法加入石墨烯的量为1.0 wt%时,拉伸强度达到了132.5 MPa,提高了68.8%;加入量增加到3.0 wt%时,电导率达6.87×10-4S·m-1,提高了8个数量级,对聚酰亚胺的性能有显著的增强作用。
摘要：
采用流变仪和激光共聚焦显微镜对不同氧化石墨烯（GO）掺量的新拌水泥浆体的流变参数以及浆体微观形态进行了定量化研究，并采用Modified-Bingham（M-B）模型和Herschel-Bulkley（H-B）模型对所测数据进行了拟合处理，提出了GO影响新拌水泥浆体的作用机理。结果表明，GO的掺入可以使新拌浆体中在减水剂作用下分散的水泥颗粒发生再次凝聚，形成重组絮凝结构，且随着GO掺量的增加，重组絮凝结构的数量越多，从而使得浆体流变性发生显著变化。一方面，新拌浆体的塑性粘度、屈服应力以及触变性随GO掺量的提高而显著增加。另一方面，GO的掺入提高了新拌浆体的临界剪切速率，使其在较大剪切速率下的流变行为仍然表现为剪切变稀；降低了浆体的剪切增稠程度，提高了浆体的稳定性。
采用流变仪和激光共聚焦显微镜对不同氧化石墨烯（GO）掺量的新拌水泥浆体的流变参数以及浆体微观形态进行了定量化研究，并采用Modified-Bingham（M-B）模型和Herschel-Bulkley（H-B）模型对所测数据进行了拟合处理，提出了GO影响新拌水泥浆体的作用机理。结果表明，GO的掺入可以使新拌浆体中在减水剂作用下分散的水泥颗粒发生再次凝聚，形成重组絮凝结构，且随着GO掺量的增加，重组絮凝结构的数量越多，从而使得浆体流变性发生显著变化。一方面，新拌浆体的塑性粘度、屈服应力以及触变性随GO掺量的提高而显著增加。另一方面，GO的掺入提高了新拌浆体的临界剪切速率，使其在较大剪切速率下的流变行为仍然表现为剪切变稀；降低了浆体的剪切增稠程度，提高了浆体的稳定性。
摘要：
碳纳米管优异的物理性质和可调的化学组成使其拥有广泛的应用前景。采用低温过程在碳骨架中引入磷原子预期带来可调的化学特性。本研究采用170℃下水热处理碳纳米管-磷酸混合物获得磷掺杂的碳纳米管。磷掺杂的碳管的磷含量为1.66%,比表面积为132 m2/g,热失重峰在纯氧环境下提升至694℃。当掺磷碳纳米管用于氧还原反应时,其起始电位为-0.20 V,电子转移数为2.60,反应电流显著高于无掺杂的碳纳米管。当其用作锂硫电池正极导电材料时,电极的起始容量为1106 mAh/g,电流密度从0.1 C提升至1 C时容量保留率为80%,100次循环的衰减率为每圈0.25%。
碳纳米管优异的物理性质和可调的化学组成使其拥有广泛的应用前景。采用低温过程在碳骨架中引入磷原子预期带来可调的化学特性。本研究采用170℃下水热处理碳纳米管-磷酸混合物获得磷掺杂的碳纳米管。磷掺杂的碳管的磷含量为1.66%,比表面积为132 m2/g,热失重峰在纯氧环境下提升至694℃。当掺磷碳纳米管用于氧还原反应时,其起始电位为-0.20 V,电子转移数为2.60,反应电流显著高于无掺杂的碳纳米管。当其用作锂硫电池正极导电材料时,电极的起始容量为1106 mAh/g,电流密度从0.1 C提升至1 C时容量保留率为80%,100次循环的衰减率为每圈0.25%。
摘要：
以新疆不粘煤为原料，三聚氰胺为氮源，硼酸为硼源，通过球磨和后续活化过程合成硼，氮掺杂及硼氮共掺杂煤基活性炭。氮吸附结果显示杂原子掺杂可提高活性炭中介孔的含量。红外和X光电子能谱结果显示，硼、氮原子存在于炭骨架中。循环伏安，恒流充放电及电化学阻抗分析说明硼、氮掺杂活性炭的电化学性能优于非掺杂活性炭。其中，硼氮共掺杂活性炭具有176 F·g-1的高比容量。循环20 000次容量保持率为96%。共掺杂活性炭优异的电化学性能归因于硼氮的协同作用。
以新疆不粘煤为原料，三聚氰胺为氮源，硼酸为硼源，通过球磨和后续活化过程合成硼，氮掺杂及硼氮共掺杂煤基活性炭。氮吸附结果显示杂原子掺杂可提高活性炭中介孔的含量。红外和X光电子能谱结果显示，硼、氮原子存在于炭骨架中。循环伏安，恒流充放电及电化学阻抗分析说明硼、氮掺杂活性炭的电化学性能优于非掺杂活性炭。其中，硼氮共掺杂活性炭具有176 F·g-1的高比容量。循环20 000次容量保持率为96%。共掺杂活性炭优异的电化学性能归因于硼氮的协同作用。
摘要：
随着石墨烯低成本宏量制备技术的突破，石墨烯的工业化应用进程已引起人们广泛关注。本文介绍了石墨烯在聚合物基复合材料领域的研究进展，侧重阐述石墨烯/聚合物复合材料在力学增强、导电/导热网络构建、防腐阻燃等方面的代表性研究成果，同时对商业化石墨烯产品及其复合材料应用进行了简单评述，探讨了石墨烯/聚合物复合材料领域目前存在的主要问题及未来发展趋势。
随着石墨烯低成本宏量制备技术的突破，石墨烯的工业化应用进程已引起人们广泛关注。本文介绍了石墨烯在聚合物基复合材料领域的研究进展，侧重阐述石墨烯/聚合物复合材料在力学增强、导电/导热网络构建、防腐阻燃等方面的代表性研究成果，同时对商业化石墨烯产品及其复合材料应用进行了简单评述，探讨了石墨烯/聚合物复合材料领域目前存在的主要问题及未来发展趋势。
摘要：
通过介绍自组装软模板法制备有序中孔炭的发展历程和基本原理，说明该方法具有操作简单、成本低、易于控制等优点。重点评述了自组装软模板法制备有序中孔炭在产物形貌控制和多级孔结构制备方面的研究进展，分析认为，今后的研究可以在拓展前驱体范围、提高宏观产物柔韧性以及导电性等方面得到进一步发展。
通过介绍自组装软模板法制备有序中孔炭的发展历程和基本原理，说明该方法具有操作简单、成本低、易于控制等优点。重点评述了自组装软模板法制备有序中孔炭在产物形貌控制和多级孔结构制备方面的研究进展，分析认为，今后的研究可以在拓展前驱体范围、提高宏观产物柔韧性以及导电性等方面得到进一步发展。
摘要：
化学气相沉积（CVD）法是近年来发展起来的制备石墨烯的新方法，具有产物质量高、生长面积大等优点，逐渐成为制备高质量石墨烯的主要方法。通过简要分析石墨烯的几种主要制备方法（胶带剥离法、化学剥离法、SiC外延生长法和CVD方法）的原理和特点，重点从结构控制、质量提高以及大面积生长等方面评述了CVD法制备石墨烯及其转移技术的研究进展，并展望了未来CVD法制备石墨烯的可能发展方向，如大面积单晶石墨烯、石墨烯带和石墨烯宏观体的制备与无损转移等。
化学气相沉积（CVD）法是近年来发展起来的制备石墨烯的新方法，具有产物质量高、生长面积大等优点，逐渐成为制备高质量石墨烯的主要方法。通过简要分析石墨烯的几种主要制备方法（胶带剥离法、化学剥离法、SiC外延生长法和CVD方法）的原理和特点，重点从结构控制、质量提高以及大面积生长等方面评述了CVD法制备石墨烯及其转移技术的研究进展，并展望了未来CVD法制备石墨烯的可能发展方向，如大面积单晶石墨烯、石墨烯带和石墨烯宏观体的制备与无损转移等。
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