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doi: 10.1016/S1872-5805(23)60724-3
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One of the most important research areas that has captured global attention is the replacement of graphite anode with other carbon materials such as hard carbon, activated carbon, carbon nanotubes, graphene, porous carbon, and carbon fiber. Although such materials have shown better electrochemical performance for lithium storage compared to graphite, their is plenty of room for improvement. One of the most effective approaches is to dope heteroatoms (e. g. nitrogen) in the structure of carbon materials to enhance their electrochemical performance when used as anode in lithium ion batteries. In this review paper, we first describe how N doping has a positive effect on lithium storage and then provide numerous selected examples of this approach being applied to various carbon materials. Then, in addition to the conventional characterization methods, the specific characterization of doped N in the structure of different carbon materials through X-ray photoelectron spectroscopy and scanning tunneling microscopy is presented, as they are able to characterize N in these structures with high (atomic) resolution. Finally, a statistical analysis is performed to discover the influence that the amount of doped N has on the specific capacity of N-doped carbon materials.
One of the most important research areas that has captured global attention is the replacement of graphite anode with other carbon materials such as hard carbon, activated carbon, carbon nanotubes, graphene, porous carbon, and carbon fiber. Although such materials have shown better electrochemical performance for lithium storage compared to graphite, their is plenty of room for improvement. One of the most effective approaches is to dope heteroatoms (e. g. nitrogen) in the structure of carbon materials to enhance their electrochemical performance when used as anode in lithium ion batteries. In this review paper, we first describe how N doping has a positive effect on lithium storage and then provide numerous selected examples of this approach being applied to various carbon materials. Then, in addition to the conventional characterization methods, the specific characterization of doped N in the structure of different carbon materials through X-ray photoelectron spectroscopy and scanning tunneling microscopy is presented, as they are able to characterize N in these structures with high (atomic) resolution. Finally, a statistical analysis is performed to discover the influence that the amount of doped N has on the specific capacity of N-doped carbon materials.
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doi: 10.1016/S1872-5805(22)60644-9
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碳点（CDs）是一种新兴的碳纳米材料，因其高比表面积、良好的分散性、丰富的表面官能团、低生物毒性和光致发光特性而受到了研究者的广泛关注。然而，低成本、大规模和绿色合成CDs仍面临挑战。本工作基于生物质玉米芯特殊的天然孔隙结构，经直接炭化制备具有定向、贯通微纳米孔道的多孔三维电极材料，内外表面同时发生电化学氧化高效制备CDs 1 A恒电流下，每克电极材料制备CDs速率达到了79.83 mg h−1。将制备的CDs与氧化石墨烯（GO）水热复合得到复合气凝胶CDs/rGO材料，经热处理后应用于钠离子电池。在1 A g−1下循环1000圈仍保持263.3 mAh g−1的容量。采用生物质玉米芯出发简单高效制备碳点，为CDs的大规模绿色制备和应用提供了新的途径和思路。
碳点（CDs）是一种新兴的碳纳米材料，因其高比表面积、良好的分散性、丰富的表面官能团、低生物毒性和光致发光特性而受到了研究者的广泛关注。然而，低成本、大规模和绿色合成CDs仍面临挑战。本工作基于生物质玉米芯特殊的天然孔隙结构，经直接炭化制备具有定向、贯通微纳米孔道的多孔三维电极材料，内外表面同时发生电化学氧化高效制备CDs 1 A恒电流下，每克电极材料制备CDs速率达到了79.83 mg h−1。将制备的CDs与氧化石墨烯（GO）水热复合得到复合气凝胶CDs/rGO材料，经热处理后应用于钠离子电池。在1 A g−1下循环1000圈仍保持263.3 mAh g−1的容量。采用生物质玉米芯出发简单高效制备碳点，为CDs的大规模绿色制备和应用提供了新的途径和思路。
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doi: 10.1016/S1872-5805(23)60731-0
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The synthesis and preparation of high-rate and long-life anode materials for sodium ion batteries (SIBs) have attracted more attention. However, the slow kinetics and massive volume growth are still the weaknesses of SIBs. Metal-organic frame and MoS2 have excellent properties for SIBs. Herein, flower-like Co9S8/MoS2 composites were designed and constructed via a simultaneous vulcanization-carbonization method at different using Co-ZIF as a precursor and adding Mo source. The effect of heterojunction on the diffusion kinetics was analyzed using density functional theory (DFT). The computational results indicate that the electronic structure is reshaped at the interface of the heterogeneous structure, exhibits typical metal properties, and exhibits enhanced electronic conductivity. In addition, the anode material Co9S8/MoS2 synthesized at 700 °C has stable structure and excellent electrochemical performance among the three samples. It is worth noting that the discharge capacity of Co9S8/MoS2-700 can fully recover from 368 mAh g−1 to 571 mAh g−1 and then stabilize at 543 mAh g−1 when the current density is restored from 4000 to 40 mA g−1. Therefore, this work offers some ideas for the rational preparation of heterojunction material, and helps in the design of anode material for composite high-performance metal sodium ion batteries.
The synthesis and preparation of high-rate and long-life anode materials for sodium ion batteries (SIBs) have attracted more attention. However, the slow kinetics and massive volume growth are still the weaknesses of SIBs. Metal-organic frame and MoS2 have excellent properties for SIBs. Herein, flower-like Co9S8/MoS2 composites were designed and constructed via a simultaneous vulcanization-carbonization method at different using Co-ZIF as a precursor and adding Mo source. The effect of heterojunction on the diffusion kinetics was analyzed using density functional theory (DFT). The computational results indicate that the electronic structure is reshaped at the interface of the heterogeneous structure, exhibits typical metal properties, and exhibits enhanced electronic conductivity. In addition, the anode material Co9S8/MoS2 synthesized at 700 °C has stable structure and excellent electrochemical performance among the three samples. It is worth noting that the discharge capacity of Co9S8/MoS2-700 can fully recover from 368 mAh g−1 to 571 mAh g−1 and then stabilize at 543 mAh g−1 when the current density is restored from 4000 to 40 mA g−1. Therefore, this work offers some ideas for the rational preparation of heterojunction material, and helps in the design of anode material for composite high-performance metal sodium ion batteries.
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doi: 10.1016/S1872-5805(23)60714-0
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较低的体积能量密度限制了当前电化学电容器的应用，而提高体积能量密度的关键在于发展具有致密化储能特性的多孔炭材料。目前，毛细致密化已成为平衡多孔炭密度和孔隙率从而提高材料体积比电容的主要方法，但仍在孔结构的精细调控方面存在不足，制约了毛细致密化多孔炭与高电压离子液体的兼容性。本文提出了碘化钾（KI）辅助的毛细致密化策略，通过在石墨烯网络中预载KI来控制毛细致密化过程，实现了对孔结构的有效调控。同时电化学性能表征结果表明KI具有增加离子到达表面积和提供赝电容的作用。基于此，所制碘化钾/石墨烯材料的密度达到0.96 g cm−3，在离子液体中的体积比电容为115 F cm−3。由该材料所组装的电化学电容器可以提供19.6 Wh L−1的体积能量密度。
较低的体积能量密度限制了当前电化学电容器的应用，而提高体积能量密度的关键在于发展具有致密化储能特性的多孔炭材料。目前，毛细致密化已成为平衡多孔炭密度和孔隙率从而提高材料体积比电容的主要方法，但仍在孔结构的精细调控方面存在不足，制约了毛细致密化多孔炭与高电压离子液体的兼容性。本文提出了碘化钾（KI）辅助的毛细致密化策略，通过在石墨烯网络中预载KI来控制毛细致密化过程，实现了对孔结构的有效调控。同时电化学性能表征结果表明KI具有增加离子到达表面积和提供赝电容的作用。基于此，所制碘化钾/石墨烯材料的密度达到0.96 g cm−3，在离子液体中的体积比电容为115 F cm−3。由该材料所组装的电化学电容器可以提供19.6 Wh L−1的体积能量密度。
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doi: 10.1016/S1872-5805(23)60725-5
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Sodium-ion batteries (SIBs) have received extensive research interests as an important supplement of lithium-ion batteries in the electrochemical energy storage field by virtue of abundant reserves and low-cost advantages of sodium element. In the past few years, carbon and their composite materials as anode materials have shown excellent sodium storage properties through structural design and composition regulation. The increasing popularity of wearable electronics has put forward higher requirements for electrode materials. Free-standing electrode is able to eliminate the massive use of electrochemical inactive binders and conductive additives, thereby favorably increasing the overall energy density of the battery system. In this review, the research progress of carbon materials (such as carbon nanofibers, carbon nanotubes, graphene, etc.) and their composites (metallic compounds and alloy-type materials) are summarized. The preparation strategies and electrochemical properties of free-standing carbon-based anodes with and without substrates are categorized and reviewed. Finally, the perspectives about research directions and future developments of free-standing carbon-based anodes for SIBs are proposed.
Sodium-ion batteries (SIBs) have received extensive research interests as an important supplement of lithium-ion batteries in the electrochemical energy storage field by virtue of abundant reserves and low-cost advantages of sodium element. In the past few years, carbon and their composite materials as anode materials have shown excellent sodium storage properties through structural design and composition regulation. The increasing popularity of wearable electronics has put forward higher requirements for electrode materials. Free-standing electrode is able to eliminate the massive use of electrochemical inactive binders and conductive additives, thereby favorably increasing the overall energy density of the battery system. In this review, the research progress of carbon materials (such as carbon nanofibers, carbon nanotubes, graphene, etc.) and their composites (metallic compounds and alloy-type materials) are summarized. The preparation strategies and electrochemical properties of free-standing carbon-based anodes with and without substrates are categorized and reviewed. Finally, the perspectives about research directions and future developments of free-standing carbon-based anodes for SIBs are proposed.
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doi: 10.1016/S1872-5805(23)60722-X
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As the massive emission of CO2 caused by the consumption of carbon has become the focus of human society, the development of renewable energy and the reduction emission of CO2 has become one of the most urgent issues to deal with in the world. As the most ideal clean energy on earth, solar energy has become a hot topic of current research. If abundant solar energy can be used to convert carbon dioxide into valued carbon-based chemicals, these two problems can be solved at the same time. There are many literatures on photocatalysis or thermal catalysis in the reduction of CO2. However, there is little research on photothermal catalysis in the reduction of CO2. In this paper, the research status of photothermal catalysis in the reduction of CO2 is summarized, showing the concept and principle of photothermal catalysis in the reduction of CO2, the classification of catalysts (new carbon materials, oxide materials, metal sulfide materials, MOF materials, layered double hydroxide materials), the modification of catalysts, and their applications in reduction of CO2. Finally, the development trend of the catalyst is forecasted. The rational development of carbon-based chemicals may help us reduce the consumption of traditional energy, reduce carbon emissions and realize the recycling of carbon.
As the massive emission of CO2 caused by the consumption of carbon has become the focus of human society, the development of renewable energy and the reduction emission of CO2 has become one of the most urgent issues to deal with in the world. As the most ideal clean energy on earth, solar energy has become a hot topic of current research. If abundant solar energy can be used to convert carbon dioxide into valued carbon-based chemicals, these two problems can be solved at the same time. There are many literatures on photocatalysis or thermal catalysis in the reduction of CO2. However, there is little research on photothermal catalysis in the reduction of CO2. In this paper, the research status of photothermal catalysis in the reduction of CO2 is summarized, showing the concept and principle of photothermal catalysis in the reduction of CO2, the classification of catalysts (new carbon materials, oxide materials, metal sulfide materials, MOF materials, layered double hydroxide materials), the modification of catalysts, and their applications in reduction of CO2. Finally, the development trend of the catalyst is forecasted. The rational development of carbon-based chemicals may help us reduce the consumption of traditional energy, reduce carbon emissions and realize the recycling of carbon.
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doi: 10.1016/S1872-5805(23)60721-8
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Supercapacitors fabricated using fiber materials are becoming noticeable electrochemical energy storage devices as they are flexible, light weight and have high energy density. These are used in electronic systems, such as information sensing, data computation and communication. These flexible supercapacitors are applied in electronic textiles because these fabric-based supercapacitors (SCs) can achieve higher power density than standard parallel plate capacitors and batteries. In this review, the effects of carbon nanotubes (CNTs), graphene and poly(3,4- ethylenedioxythiophene) : poly(styrene sulfonate) (PEDOT:PSS) on the electrochemical performance of fibers based on their compositions, spinning and fabrication conditions have been explained in detail in the context of wearable energy storage devices.
Supercapacitors fabricated using fiber materials are becoming noticeable electrochemical energy storage devices as they are flexible, light weight and have high energy density. These are used in electronic systems, such as information sensing, data computation and communication. These flexible supercapacitors are applied in electronic textiles because these fabric-based supercapacitors (SCs) can achieve higher power density than standard parallel plate capacitors and batteries. In this review, the effects of carbon nanotubes (CNTs), graphene and poly(3,4- ethylenedioxythiophene) : poly(styrene sulfonate) (PEDOT:PSS) on the electrochemical performance of fibers based on their compositions, spinning and fabrication conditions have been explained in detail in the context of wearable energy storage devices.
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doi: 10.1016/S1872-5805(23)60713-9
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As the sulfur host as a reactor for redox reactions and determines the electrochemical properties of the sulfur cathode, tailor-made fabrication of sulfur host is very effective to solve the main challenges of lithium-sulfur (Li-S) batteries, such as the shuttle effect and sluggish redox kinetics. Under this guidance, sulfur is in-situ confined in a hollow thin-walled C/Mo2C reactor with size smaller than 7 nm, in which these nanosized primary particles are connected with each other forming secondary microsized particles. In such composites, the nanoscale sulfur core and continuous conductive network can facilitate lithium-ion and electron transport. Moreover, the microporous C/Mo2C shell can mitigate the outward diffusion of polysulfides via the physical/chemical obstruction and enhance redox kinetics through effective catalysis conversion of polysulfides. Stem from these merits, the S@C/Mo2C cathode materials can achieve a high reversible capacity of 1210 mA h g−1 at 0.5 C with a low capacity fading rate of 0.127% per cycle over 300 cycles and high rate performance (780 mA h g−1 at 3.0 C). The present work may shed light on designing advanced sulfur host for Li-S batteries with high rate performance and high cycle stability.
As the sulfur host as a reactor for redox reactions and determines the electrochemical properties of the sulfur cathode, tailor-made fabrication of sulfur host is very effective to solve the main challenges of lithium-sulfur (Li-S) batteries, such as the shuttle effect and sluggish redox kinetics. Under this guidance, sulfur is in-situ confined in a hollow thin-walled C/Mo2C reactor with size smaller than 7 nm, in which these nanosized primary particles are connected with each other forming secondary microsized particles. In such composites, the nanoscale sulfur core and continuous conductive network can facilitate lithium-ion and electron transport. Moreover, the microporous C/Mo2C shell can mitigate the outward diffusion of polysulfides via the physical/chemical obstruction and enhance redox kinetics through effective catalysis conversion of polysulfides. Stem from these merits, the S@C/Mo2C cathode materials can achieve a high reversible capacity of 1210 mA h g−1 at 0.5 C with a low capacity fading rate of 0.127% per cycle over 300 cycles and high rate performance (780 mA h g−1 at 3.0 C). The present work may shed light on designing advanced sulfur host for Li-S batteries with high rate performance and high cycle stability.
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doi: 10.1016/S1872-5805(23)60705-X
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An anodized carbon fiber tow is sized continuously. The effects of aqueous polyurethane as the sizing agent for enhancing the interfacial properties of carbon fiber reinforced polyurethane composite has been investigated by mutliple techniques, including interlaminar shear strength (ILSS), elemental and functional group analysis, thermal gravimetric analysis, and differential scanning calorimetry. The results show the polyurethane sizing agent can significantly improve the interfacial properties of the composites. The ILSS of the sized carbon fiber reinforced composite is increased by 17.5% (from 39.5 to 46.4 MPa) compared with that of the oxidized carbon fiber reinforced counterpart. Treating the sized carbon fiber reinforced composite at 170 °C can further increase the ILSS by 9.5%, to 50.8 MPa. It is considered that the sizing agent can interact with the oxygen-contained functional groups on the oxidized carbon fiber surface and form hydrogen bonds with the matrix resin. Upon heating at 170 °C, the blocking groups in the sizing agent are unblocked to expose the isocyanate roots that can react with the carbamate of the matrix to generate allophanate. It can draw the conclusions that the polyurethane sizing agent is suitable to improve the interfacial performance of carbon fiber reinforced polyurethane resin composites. Unsealing the sizing agent at high temperature after curing can further improve the interfacial performance of the composite.
An anodized carbon fiber tow is sized continuously. The effects of aqueous polyurethane as the sizing agent for enhancing the interfacial properties of carbon fiber reinforced polyurethane composite has been investigated by mutliple techniques, including interlaminar shear strength (ILSS), elemental and functional group analysis, thermal gravimetric analysis, and differential scanning calorimetry. The results show the polyurethane sizing agent can significantly improve the interfacial properties of the composites. The ILSS of the sized carbon fiber reinforced composite is increased by 17.5% (from 39.5 to 46.4 MPa) compared with that of the oxidized carbon fiber reinforced counterpart. Treating the sized carbon fiber reinforced composite at 170 °C can further increase the ILSS by 9.5%, to 50.8 MPa. It is considered that the sizing agent can interact with the oxygen-contained functional groups on the oxidized carbon fiber surface and form hydrogen bonds with the matrix resin. Upon heating at 170 °C, the blocking groups in the sizing agent are unblocked to expose the isocyanate roots that can react with the carbamate of the matrix to generate allophanate. It can draw the conclusions that the polyurethane sizing agent is suitable to improve the interfacial performance of carbon fiber reinforced polyurethane resin composites. Unsealing the sizing agent at high temperature after curing can further improve the interfacial performance of the composite.
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doi: 10.1016/S1872-5805(23)60704-8
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In this study, a novel pantograph carbon slider (PCS) was designed by incorporating sulfonated graphene (SG), resulting in the enhancement of mechanical and wear performances of the slider. The PCS was prepared through mold pressing, hot extrusion and roasting. A mock current-carrying wear test showed that the wear rate of the PCS reinforced by 1 wt % SG was lowered by 50.0% in the normal environment and 51.0% in a rainy weather environment, compared with the control group. In addition, the flexural strength of the samples with SG was 41.8% higher than to those without SG. Moreover, the dragging effect of SG decreased the number of random cracks and increased the compactness of fracture surface of the slider materials. These changes markedly inhibited the electro-erosion of the PCS, thus improving mechanical and wear resistance significantly.
In this study, a novel pantograph carbon slider (PCS) was designed by incorporating sulfonated graphene (SG), resulting in the enhancement of mechanical and wear performances of the slider. The PCS was prepared through mold pressing, hot extrusion and roasting. A mock current-carrying wear test showed that the wear rate of the PCS reinforced by 1 wt % SG was lowered by 50.0% in the normal environment and 51.0% in a rainy weather environment, compared with the control group. In addition, the flexural strength of the samples with SG was 41.8% higher than to those without SG. Moreover, the dragging effect of SG decreased the number of random cracks and increased the compactness of fracture surface of the slider materials. These changes markedly inhibited the electro-erosion of the PCS, thus improving mechanical and wear resistance significantly.
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doi: 10.1016/S1872-5805(22)60647-4
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Graphene/Ni-NiO@C was prepared by dissolving nickel acetate and glucose in water, mixed with a graphene oxide (GO) aqueous suspension, hydrothermal treated at 180 °C for 24 h, carbonized at 700 °C for 3h in Ar and calcined at 300 °C for 3 h in air. Results indicated that Ni(OH)2 formed during hydrothermal treatment was coated with char derived from glucose and converted to metallic Ni in carbonization, which was partly oxidized to NiO in calcination. When used as the anode material of a lithium-ion battery, it exhibited a high initial capacity of 711.6 mA h g−1, which increased to 772.1 mA h g−1 after 300 cycles. As a comparison, the sample without adding GO had a much lower initial capacity of 584.7 mA h g−1, which decreased to 148.8 mA h g−1 after 300 cycles. Carbon coating on Ni-NiO nanoparticles inhibited their aggregation. GO addition led to the formation of a conducting network, alleviated the large volume expansion during lithiation, restrained the electrode cracking during cycling and increased surface area for easy access of the electrolyte. These factors jointly contributed to the apparent improvement in the electrochemical performance of the graphene/Ni-NiO@C anode.
Graphene/Ni-NiO@C was prepared by dissolving nickel acetate and glucose in water, mixed with a graphene oxide (GO) aqueous suspension, hydrothermal treated at 180 °C for 24 h, carbonized at 700 °C for 3h in Ar and calcined at 300 °C for 3 h in air. Results indicated that Ni(OH)2 formed during hydrothermal treatment was coated with char derived from glucose and converted to metallic Ni in carbonization, which was partly oxidized to NiO in calcination. When used as the anode material of a lithium-ion battery, it exhibited a high initial capacity of 711.6 mA h g−1, which increased to 772.1 mA h g−1 after 300 cycles. As a comparison, the sample without adding GO had a much lower initial capacity of 584.7 mA h g−1, which decreased to 148.8 mA h g−1 after 300 cycles. Carbon coating on Ni-NiO nanoparticles inhibited their aggregation. GO addition led to the formation of a conducting network, alleviated the large volume expansion during lithiation, restrained the electrode cracking during cycling and increased surface area for easy access of the electrolyte. These factors jointly contributed to the apparent improvement in the electrochemical performance of the graphene/Ni-NiO@C anode.
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doi: 10.1016/S1872-5805(23)60709-7
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Mesophase pitch-based carbon fibers (MPCFs) have the characteristics of high modulus, low resistivity and high thermal conductivity, so it has broad application prospects in many fields. High-performance carbon fibers were prepared from naphthalene-based mesophase pitches synthesized by HF/BF3 catalytic one-step method (AR-MP) and AlCl3 catalytic two-step method (N-MP), respectively. These two mesophase pitches, and spun pitch fibers, pre-oxidized fibers carbonized fibers and graphitized fibers produced from them were characterized by TG-MS, FT-IR, 13C-NMR, MALDI-TOF-MS, XRD, SEM and elemental analysis. The molecular structures and properties of mesophase pitches prepared by different catalytic polymerization processes were compared, and the effects of molecular structure differences of mesophase pitches on the structure and properties of carbon fibers were further explored. In comparison to N-MP, AR-MP possesses a rod-like semi-rigid molecular configuration containing more naphthenic structures and methyl side chains. The pre-oxidized fibers derived from AR-MP show better carbon layer orientation, thus their graphitized fibers have higher thermal conductivity of 716 W/m·K. N-MP with higher aromaticity possesses a disc-like rigid molecular configuration. Therefore, the graphitized fibers prepared from N-MP have higher tensile strength of 3.47 GPa due to their fewer resulted defects during the preparation. The molecular structures of AR-MP and N-MP have an obvious influence on the structure and properties of their graphited fibers.
Mesophase pitch-based carbon fibers (MPCFs) have the characteristics of high modulus, low resistivity and high thermal conductivity, so it has broad application prospects in many fields. High-performance carbon fibers were prepared from naphthalene-based mesophase pitches synthesized by HF/BF3 catalytic one-step method (AR-MP) and AlCl3 catalytic two-step method (N-MP), respectively. These two mesophase pitches, and spun pitch fibers, pre-oxidized fibers carbonized fibers and graphitized fibers produced from them were characterized by TG-MS, FT-IR, 13C-NMR, MALDI-TOF-MS, XRD, SEM and elemental analysis. The molecular structures and properties of mesophase pitches prepared by different catalytic polymerization processes were compared, and the effects of molecular structure differences of mesophase pitches on the structure and properties of carbon fibers were further explored. In comparison to N-MP, AR-MP possesses a rod-like semi-rigid molecular configuration containing more naphthenic structures and methyl side chains. The pre-oxidized fibers derived from AR-MP show better carbon layer orientation, thus their graphitized fibers have higher thermal conductivity of 716 W/m·K. N-MP with higher aromaticity possesses a disc-like rigid molecular configuration. Therefore, the graphitized fibers prepared from N-MP have higher tensile strength of 3.47 GPa due to their fewer resulted defects during the preparation. The molecular structures of AR-MP and N-MP have an obvious influence on the structure and properties of their graphited fibers.
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doi: 10.1016/S1872-5805(21)60059-8
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Graphite is one of the most promising anode materials for potassium-ion batteries (PIBs) due to its low cost and stable discharge plateau. However, its poor rate performance still needs to be improved. Herein, a novel graphitic anode was designed from commercial mesocarbon microbeads (MCMB) by KOH treatment. Through limited oxidation and slight intercalation, an expanded layer with enlarged interlayer spacing formed on the surface of MCMB, by which the K+ diffusion rate was significantly improved. When served as the PIB anode, this modified MCMB delivered a high plateau capacity below 0.25 V (271 mAh g−1), superior rate capability (160 mAh g−1 at 1.0 A g−1), excellent cycling stability (about 184 mAh g−1 after 100 cycles at 0.1 A g−1), and high initial coulombic efficiency with carboxymethyl cellulose as binder (79.2%). This work provides a facile strategy to prepare graphitic materials with superior potassium storage property.
Graphite is one of the most promising anode materials for potassium-ion batteries (PIBs) due to its low cost and stable discharge plateau. However, its poor rate performance still needs to be improved. Herein, a novel graphitic anode was designed from commercial mesocarbon microbeads (MCMB) by KOH treatment. Through limited oxidation and slight intercalation, an expanded layer with enlarged interlayer spacing formed on the surface of MCMB, by which the K+ diffusion rate was significantly improved. When served as the PIB anode, this modified MCMB delivered a high plateau capacity below 0.25 V (271 mAh g−1), superior rate capability (160 mAh g−1 at 1.0 A g−1), excellent cycling stability (about 184 mAh g−1 after 100 cycles at 0.1 A g−1), and high initial coulombic efficiency with carboxymethyl cellulose as binder (79.2%). This work provides a facile strategy to prepare graphitic materials with superior potassium storage property.
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doi: 10.1016/S1872-5805(23)60708-5
摘要:
As a key material in nuclear reactors, the microstructure of nuclear graphite is affected by the high-flux irradiation in reactors. The damage behavior of nuclear graphite by irradiation is important for the safe operation of reactors. In order to understand the damage behavior of nuclear graphite by irradiation, IG-110 nuclear graphite, as a representative of nuclear graphite, was chosen to investigate the evolution of morphology and microstructure caused by 7 MeV Xe26+ irradiation. The topography and microstructure of IG-110 were characterized by scanning electron microscopy, atomic force microscopy, grazing incidence X-ray diffraction, Raman spectroscopy and nano-indentation. Results indicate that after 7 MeV Xe26+ irradiation at a dose of 0.11 dpa, the ridge-like structure appears on the surface of the IG-110 graphite, mainly in the binder region, and the surface roughness increases slightly. With a further increase of the irradiation dose, the ridge-like structure also appears in the filler region. At a dose of 0.55 dpa, the shrinkage of pores increases accompanied by closing of pores, and the surface roughness also increases. The changes in topography and microstructure of IG-110 graphite caused by irradiation are attributed to the expansion of graphite along the C-axis direction. Defect density and the degree of in-plane disorder in the graphene sheets increases with the increase of irradiation dose. The mechanical properties of IG-110 graphite increase first then decrease with increasing the irradiation dose. The increase of mechanical properties is caused by dislocation pinning and closing of fine pores, while the decrease of mechanical properties is attributed to the increase of porosity and the generation of the amorphous structure.
As a key material in nuclear reactors, the microstructure of nuclear graphite is affected by the high-flux irradiation in reactors. The damage behavior of nuclear graphite by irradiation is important for the safe operation of reactors. In order to understand the damage behavior of nuclear graphite by irradiation, IG-110 nuclear graphite, as a representative of nuclear graphite, was chosen to investigate the evolution of morphology and microstructure caused by 7 MeV Xe26+ irradiation. The topography and microstructure of IG-110 were characterized by scanning electron microscopy, atomic force microscopy, grazing incidence X-ray diffraction, Raman spectroscopy and nano-indentation. Results indicate that after 7 MeV Xe26+ irradiation at a dose of 0.11 dpa, the ridge-like structure appears on the surface of the IG-110 graphite, mainly in the binder region, and the surface roughness increases slightly. With a further increase of the irradiation dose, the ridge-like structure also appears in the filler region. At a dose of 0.55 dpa, the shrinkage of pores increases accompanied by closing of pores, and the surface roughness also increases. The changes in topography and microstructure of IG-110 graphite caused by irradiation are attributed to the expansion of graphite along the C-axis direction. Defect density and the degree of in-plane disorder in the graphene sheets increases with the increase of irradiation dose. The mechanical properties of IG-110 graphite increase first then decrease with increasing the irradiation dose. The increase of mechanical properties is caused by dislocation pinning and closing of fine pores, while the decrease of mechanical properties is attributed to the increase of porosity and the generation of the amorphous structure.
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doi: 10.1016/S1872-5805(23)60732-2
摘要:
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(23)60730-9
摘要:
MXene is a sort of revolutionary two-dimensional material that possesses distinctive laminated structure and composition of transition metal carbides. It exhibits special physicochemical characteristics including large specific surface area, admirable conductivity, mechanical property and photothermal behaviors, which enable it to represent application value. Furthermore, for pursuing broader application, MXene is usually compounded with carbon-based materials to strengthen comprehensive performances. Therefore, MXene and MXene- carbon based composites has been attracted more attention in various fields such as electronics, biosensors and biomedicine over the past few years. In this review, the fabrication, modification and biomedical applications concerning MXene and MXene-carbon based materials will be introduced. In particular, this review will focus on biomedical applications of MXene and MXene-carbon based composites such as biosensors, antibacterial materials, drug delivery, and the diagnosis and treatment of diseases.
MXene is a sort of revolutionary two-dimensional material that possesses distinctive laminated structure and composition of transition metal carbides. It exhibits special physicochemical characteristics including large specific surface area, admirable conductivity, mechanical property and photothermal behaviors, which enable it to represent application value. Furthermore, for pursuing broader application, MXene is usually compounded with carbon-based materials to strengthen comprehensive performances. Therefore, MXene and MXene- carbon based composites has been attracted more attention in various fields such as electronics, biosensors and biomedicine over the past few years. In this review, the fabrication, modification and biomedical applications concerning MXene and MXene-carbon based materials will be introduced. In particular, this review will focus on biomedical applications of MXene and MXene-carbon based composites such as biosensors, antibacterial materials, drug delivery, and the diagnosis and treatment of diseases.
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doi: 10.1016/S1872-5805(23)60729-2
摘要:
超薄锂金属（≤50 μm）是下一代高比能锂金属电池负极选择。然而纯锂质软、易脆，其机械加工性较差，导致超薄锂箔的制备工艺复杂、成本高昂；此外相比于较厚的锂金属负极，超薄锂金属负极往往呈现更差的电化学循环性能。本文提出一种“自下而上”的策略制备10-50 μm厚度可控的超薄还原氧化石墨烯/锂金属（rGO/Li）复合箔材，其结构由大量无序随机的rGO片层非平行排列并均匀分散在锂金属内。制备过程中首先将还原氧化石墨烯（rGO）粉片与熔融锂金属在200 °C下搅拌复合，获得微米级的还原氧化石墨烯/锂复合粉片，之后将复合粉片作为原材料进一步通过反复辊压制备出结构均匀、超薄的复合箔材，该方法具有一定的规模化潜力。不同于其他所报道的rGO层状薄膜结构，在复合箔材中rGO片层随机无序分散形成三维网络，有利于实现锂的均匀沉积/剥离。所制备的50 μm超薄无序结构rGO/Li复合箔材负极在对称电池中以1 mA cm−2、1 mAh cm−2条件在醚基电解液中可稳定循环1600小时以上，在与硫化聚丙烯腈（SPAN）正极组配全电池以0.2 C倍率循环220次后比容量高达~675 mAh g−1，优于使用同厚度纯锂负极的电池。
超薄锂金属（≤50 μm）是下一代高比能锂金属电池负极选择。然而纯锂质软、易脆，其机械加工性较差，导致超薄锂箔的制备工艺复杂、成本高昂；此外相比于较厚的锂金属负极，超薄锂金属负极往往呈现更差的电化学循环性能。本文提出一种“自下而上”的策略制备10-50 μm厚度可控的超薄还原氧化石墨烯/锂金属（rGO/Li）复合箔材，其结构由大量无序随机的rGO片层非平行排列并均匀分散在锂金属内。制备过程中首先将还原氧化石墨烯（rGO）粉片与熔融锂金属在200 °C下搅拌复合，获得微米级的还原氧化石墨烯/锂复合粉片，之后将复合粉片作为原材料进一步通过反复辊压制备出结构均匀、超薄的复合箔材，该方法具有一定的规模化潜力。不同于其他所报道的rGO层状薄膜结构，在复合箔材中rGO片层随机无序分散形成三维网络，有利于实现锂的均匀沉积/剥离。所制备的50 μm超薄无序结构rGO/Li复合箔材负极在对称电池中以1 mA cm−2、1 mAh cm−2条件在醚基电解液中可稳定循环1600小时以上，在与硫化聚丙烯腈（SPAN）正极组配全电池以0.2 C倍率循环220次后比容量高达~675 mAh g−1，优于使用同厚度纯锂负极的电池。
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doi: 10.1016/S1872-5805(23)60728-0
摘要:
Carbon fibers (CFs) were surface-modified by a surfactant (ferrocenemethyl)dodecyldimethylammonium bromide (FDDA) for changing the surface properties. Results showed that the FDDA adsorbed onto CFs 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 CFs have little effect on the tensile strength of CFs. Furthermore, 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 CFs exhibited significantly improved interfacial adhesion properties in composites. This method provides a potential approach for preparing recyclable CF/resin composites.
Carbon fibers (CFs) were surface-modified by a surfactant (ferrocenemethyl)dodecyldimethylammonium bromide (FDDA) for changing the surface properties. Results showed that the FDDA adsorbed onto CFs 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 CFs have little effect on the tensile strength of CFs. Furthermore, 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 CFs exhibited significantly improved interfacial adhesion properties in composites. This method provides a potential approach for preparing recyclable CF/resin composites.
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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)60727-9
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作为锂离子电池和超级电容器的结合，锂离子电容器由于其兼备电池和电容器的优点而受到了广泛的关注。然而由于其正极双电层电容行为的储能机理，锂离子电容器的能量特性受到了很大的限制。因此，为了从根本上增强锂离子电容器正极材料性能，本研究提出了双离子电容器的储能机理。以柠檬酸钾/镁/铁为原料，合成了兼备石墨质结构与层次化多孔结构的石墨质多孔碳，并以其为正极材料，实现了兼具锂离子电容器正极离子吸附行为与双离子电池正极阴离子插层行为的双离子电容储能机理。由于石墨质多孔碳结构中石墨质结构在高电位下由阴离子插层反应贡献的额外平台容量以及对于材料导电性的增强，石墨质多孔碳正极材料的能量特性远超多孔碳及人造石墨正极，实现了从储能机理的层面的器件性能增强。
作为锂离子电池和超级电容器的结合，锂离子电容器由于其兼备电池和电容器的优点而受到了广泛的关注。然而由于其正极双电层电容行为的储能机理，锂离子电容器的能量特性受到了很大的限制。因此，为了从根本上增强锂离子电容器正极材料性能，本研究提出了双离子电容器的储能机理。以柠檬酸钾/镁/铁为原料，合成了兼备石墨质结构与层次化多孔结构的石墨质多孔碳，并以其为正极材料，实现了兼具锂离子电容器正极离子吸附行为与双离子电池正极阴离子插层行为的双离子电容储能机理。由于石墨质多孔碳结构中石墨质结构在高电位下由阴离子插层反应贡献的额外平台容量以及对于材料导电性的增强，石墨质多孔碳正极材料的能量特性远超多孔碳及人造石墨正极，实现了从储能机理的层面的器件性能增强。
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doi: 10.1016/S1872-5805(23)60726-7
摘要:
In this work, we first designed and fabricated the nanocomposite of zinc sulfide nanodots and 3D N-S co-doped carbon nanosheets (ZnS/NS-CN) successfully derived from waste biomass orange peels using ZnCl2 as hard templates and zinc source, melamine and thiourea as nitrogen and sulfur sources by an elevated temperature sintering and latter etching treatment. When applied to Li-ion batteries, ZnS/NS-CN exhibits high reversible capacity (853.5 mAh g−1 at 0.1 A g−1 after 300 cycles), excellent long-term cycling stability (70.1% capacity retention after 1000 cycles at 5 A g−1) and an outstanding rate capability. Besides, the ZnS/NS-CN//LiNiCoMnO2 full cells assembled and tested at 0.5-4 V exhibited excellent battery performance (140.4 mAh g−1 at 0.2 C after 150 cycles with an energy density of 132.4 Wh kg−1). Such excellent electrochemical performance shows that the anode with reasonable design has a great prospect in lithium-ion batteries (LIBs).
In this work, we first designed and fabricated the nanocomposite of zinc sulfide nanodots and 3D N-S co-doped carbon nanosheets (ZnS/NS-CN) successfully derived from waste biomass orange peels using ZnCl2 as hard templates and zinc source, melamine and thiourea as nitrogen and sulfur sources by an elevated temperature sintering and latter etching treatment. When applied to Li-ion batteries, ZnS/NS-CN exhibits high reversible capacity (853.5 mAh g−1 at 0.1 A g−1 after 300 cycles), excellent long-term cycling stability (70.1% capacity retention after 1000 cycles at 5 A g−1) and an outstanding rate capability. Besides, the ZnS/NS-CN//LiNiCoMnO2 full cells assembled and tested at 0.5-4 V exhibited excellent battery performance (140.4 mAh g−1 at 0.2 C after 150 cycles with an energy density of 132.4 Wh kg−1). Such excellent electrochemical performance shows that the anode with reasonable design has a great prospect in lithium-ion batteries (LIBs).
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doi: 10.1016/S1872-5805(23)60723-1
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The design of low-cost green catalyst for nitrobenzene (NB) hydrogenation is highly desirable for aniline production. Here, N-doped carbons supported highly-dispersed Co particles were obtained by hydrothermal treatment of glucose, followed by pyrolysis of urea, hydrochar, and cobalt nitrate in one-pot. The effect of pyrolysis temperatures on the structure of catalysts was studied, and the activity was highly affected by the surface areas, Co-loadings and Co-Nx coordination effect in catalysts. Co@NCG-800 as carbonized at 800 °C with 10% Co-species in precursor had extraordinary activity for NB hydrogenation, achieving a full conversion and 99% aniline selectivity in isopropanol under condition of 100 °C and 1 MPa H2 pressure for 2.5 h. NB conversion and aniline selectivity over the catalysts remained almost unchanged even after six recycles, due to strong coordination between N-species and Co-species. The reaction system not only showed superior NB activity but also indicated a green durable catalytic process, facilitating facile operation, easy separation, and catalyst reusability.
The design of low-cost green catalyst for nitrobenzene (NB) hydrogenation is highly desirable for aniline production. Here, N-doped carbons supported highly-dispersed Co particles were obtained by hydrothermal treatment of glucose, followed by pyrolysis of urea, hydrochar, and cobalt nitrate in one-pot. The effect of pyrolysis temperatures on the structure of catalysts was studied, and the activity was highly affected by the surface areas, Co-loadings and Co-Nx coordination effect in catalysts. Co@NCG-800 as carbonized at 800 °C with 10% Co-species in precursor had extraordinary activity for NB hydrogenation, achieving a full conversion and 99% aniline selectivity in isopropanol under condition of 100 °C and 1 MPa H2 pressure for 2.5 h. NB conversion and aniline selectivity over the catalysts remained almost unchanged even after six recycles, due to strong coordination between N-species and Co-species. The reaction system not only showed superior NB activity but also indicated a green durable catalytic process, facilitating facile operation, easy separation, and catalyst reusability.
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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(22)60630-9
摘要:
钠离子电池因资源丰富及成本低等优势，在大规模储能领域备受关注。炭材料作为钠离子电池实用化进程中的关键负极材料，具有高容量、低嵌钠平台、易调控且稳定性好等特点，引起了研究者的广泛关注。掺杂原子可改善炭材料的微观与电子结构，是提升储钠性能的有效途径。常见的杂原子包括N、S、O、P、B等，其中硫原子因其较大的半径能显著扩大层间距、增加缺陷与活性位点，被广泛用于炭负极材料的掺杂改性。本文综述了近年来硫掺杂炭材料的设计制备及在钠离子电池负极中的研究进展，分析了硫掺杂对碳结构的调控机理与改善电池性能的作用机制，最后针对目前面临的挑战和可能的解决方案进行了总结和展望，以期推动硫掺杂炭负极材料在钠离子电池中的实用化进程。
钠离子电池因资源丰富及成本低等优势，在大规模储能领域备受关注。炭材料作为钠离子电池实用化进程中的关键负极材料，具有高容量、低嵌钠平台、易调控且稳定性好等特点，引起了研究者的广泛关注。掺杂原子可改善炭材料的微观与电子结构，是提升储钠性能的有效途径。常见的杂原子包括N、S、O、P、B等，其中硫原子因其较大的半径能显著扩大层间距、增加缺陷与活性位点，被广泛用于炭负极材料的掺杂改性。本文综述了近年来硫掺杂炭材料的设计制备及在钠离子电池负极中的研究进展，分析了硫掺杂对碳结构的调控机理与改善电池性能的作用机制，最后针对目前面临的挑战和可能的解决方案进行了总结和展望，以期推动硫掺杂炭负极材料在钠离子电池中的实用化进程。
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doi: 10.1016/S1872-5805(23)60707-3
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The phenolic resin was coated on the surface of nano-Si by microencapsulation technology, and then carbonized under the Ar protection to prepare nano-Si@C nanocomposite. Firstly, four mass ratios of phenolic resin to nano-Si (1∶2, 1∶4, 1∶6, 1∶8) were employed to prepare nano-Si@C nanocomposites. The obtained average thickness of amorphous carbon coating was 7, 4.5, 3.7, 2.8 nm, respectively. By comparing the cycling and rate capability, the best electrochemical performance was obtained when the mass ratio of phenolic resin to nano Si was 1∶4, that is, the amorphous carbon coating was 4.5 nm.. The electrochemical properties of optimized nano-Si@C nanocomposite was then evaluated comprehensively, which exhibited excellent electrochemical performance as anode material for Li-ion batteries. Under a current density of 100 mAg−1, the nano-Si@C nanocomposite delivered a first discharge specific capacity of 2382 mAhg−1, first charge specific capacity of 1667 mAhg−1, and a first coulombic efficiency of 70%. Moreover, the discharge specific capacity of 835.6 mAhg−1 could be retained after 200 cycles with a high coulombic efficiency of 99.2%. In addition, nano-Si@C nanocomposite also demonstrated superior rate performance. Under the current densities of 100, 200, 500, 1000 and 2000 mAg−1, the average discharge specific capacities were 1716.4, 1231.6, 911.7, 676.1, and 339.8 mAhg−1, respectively. When the current density returned to 100 mAg−1, the specific capacity restored to 1326.4 mAhg−1.
The phenolic resin was coated on the surface of nano-Si by microencapsulation technology, and then carbonized under the Ar protection to prepare nano-Si@C nanocomposite. Firstly, four mass ratios of phenolic resin to nano-Si (1∶2, 1∶4, 1∶6, 1∶8) were employed to prepare nano-Si@C nanocomposites. The obtained average thickness of amorphous carbon coating was 7, 4.5, 3.7, 2.8 nm, respectively. By comparing the cycling and rate capability, the best electrochemical performance was obtained when the mass ratio of phenolic resin to nano Si was 1∶4, that is, the amorphous carbon coating was 4.5 nm.. The electrochemical properties of optimized nano-Si@C nanocomposite was then evaluated comprehensively, which exhibited excellent electrochemical performance as anode material for Li-ion batteries. Under a current density of 100 mAg−1, the nano-Si@C nanocomposite delivered a first discharge specific capacity of 2382 mAhg−1, first charge specific capacity of 1667 mAhg−1, and a first coulombic efficiency of 70%. Moreover, the discharge specific capacity of 835.6 mAhg−1 could be retained after 200 cycles with a high coulombic efficiency of 99.2%. In addition, nano-Si@C nanocomposite also demonstrated superior rate performance. Under the current densities of 100, 200, 500, 1000 and 2000 mAg−1, the average discharge specific capacities were 1716.4, 1231.6, 911.7, 676.1, and 339.8 mAhg−1, respectively. When the current density returned to 100 mAg−1, the specific capacity restored to 1326.4 mAhg−1.
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doi: 10.1016/S1872-5805(23)60706-1
摘要:
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
摘要:
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
摘要:
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(1): 1-17.
doi: 10.1016/S1872-5805(23)60710-3
摘要:
多孔炭材料具有质量轻、比表面积大、导电性好和稳定性高的优点，在电化学储能领域得到了广泛的应用。近几十年来，多孔炭材料的结构构筑和功能化设计取得了较大的进步。本文以多孔炭在不同储能器件中的应用发展为导向，结合多孔炭结构设计和功能化发展，综述了其在锂离子电池、锂空气电池、锂硫电池、锂负极保护、钠离子电池、钾离子电池等电化学储能器件中的研究成果和进展，最后总结了多孔炭的结构控制和功能化的策略，并展望了多孔炭材料未来研究的方向和挑战。
多孔炭材料具有质量轻、比表面积大、导电性好和稳定性高的优点，在电化学储能领域得到了广泛的应用。近几十年来，多孔炭材料的结构构筑和功能化设计取得了较大的进步。本文以多孔炭在不同储能器件中的应用发展为导向，结合多孔炭结构设计和功能化发展，综述了其在锂离子电池、锂空气电池、锂硫电池、锂负极保护、钠离子电池、钾离子电池等电化学储能器件中的研究成果和进展，最后总结了多孔炭的结构控制和功能化的策略，并展望了多孔炭材料未来研究的方向和挑战。
2023, 38(1): 18-39.
doi: 10.1016/S1872-5805(23)60719-X
摘要:
Fibrous graphite materials are highly attractive due to their unique morphologies, high degree of orientation of their graphite microcrystallites, extremely good mechanical and conductive properties, fascinating growth mechanisms, diverse preparation methods and potential applications. This review summarizes the preparation methods, Raman spectra and the growth mechanisms of graphite whiskers, columnar carbons with cone-shaped top cones, and needle- and rod-like polyhedral crystals, and their optical, electrical and magnetic properties and applications are outlined.
Fibrous graphite materials are highly attractive due to their unique morphologies, high degree of orientation of their graphite microcrystallites, extremely good mechanical and conductive properties, fascinating growth mechanisms, diverse preparation methods and potential applications. This review summarizes the preparation methods, Raman spectra and the growth mechanisms of graphite whiskers, columnar carbons with cone-shaped top cones, and needle- and rod-like polyhedral crystals, and their optical, electrical and magnetic properties and applications are outlined.
2023, 38(1): 40-72.
doi: 10.1016/S1872-5805(23)60718-8
摘要:
Sodium-ion batteries (SIBs) have attracted tremendous attention for large-scale stationary grid energy storage. With the upcoming commercialization of SIBs in the foreseeable future, developing high-performance carbon anodes from sustainable biomass is becoming increasingly important in the preparation of cost-effective SIBs. This review summarizes advanced carbon anodes for SIBs derived from various lignocellulose biomass waste. The history of our understanding of sodium storage mechanisms in carbon anodes is first discussed to clarify their structure-performance relationships. Conventional preparation strategies including pore structure design, heteroatom doping, control of the graphitic structure, and morphology control and their effects on the sodium storage capability of biomass-derived carbon anodes are then discussed. Finally, the practical applications, future research directions and challenges for the use of biomass-derived carbon anodes for SIBs are discussed from the aspects of synthesis methods, microstructure control and production costs.
Sodium-ion batteries (SIBs) have attracted tremendous attention for large-scale stationary grid energy storage. With the upcoming commercialization of SIBs in the foreseeable future, developing high-performance carbon anodes from sustainable biomass is becoming increasingly important in the preparation of cost-effective SIBs. This review summarizes advanced carbon anodes for SIBs derived from various lignocellulose biomass waste. The history of our understanding of sodium storage mechanisms in carbon anodes is first discussed to clarify their structure-performance relationships. Conventional preparation strategies including pore structure design, heteroatom doping, control of the graphitic structure, and morphology control and their effects on the sodium storage capability of biomass-derived carbon anodes are then discussed. Finally, the practical applications, future research directions and challenges for the use of biomass-derived carbon anodes for SIBs are discussed from the aspects of synthesis methods, microstructure control and production costs.
2023, 38(1): 73-95.
doi: 10.1016/S1872-5805(23)60717-6
摘要:
Natural graphite has many excellent properties such as high thermal and electrical conductivities, high temperature resistance, corrosion resistance, and radiation tolerance. It is widely used in many fields such as thermal management, battery electrodes, and the nuclear industry. The carbon content is an important factor that limits the applications of natural graphite minerals, but the impurities are difficult to remove from high-grade graphite minerals. This review discusses the types of natural graphite and mineral resources, followed by a discussion of traditional graphite purification processes and new methods to obtain high-purity graphite. Recent research on the development of natural graphite for use in thermal management, battery electrodes and the nuclear industry are summarized and the future applications of natural graphite are discussed.
Natural graphite has many excellent properties such as high thermal and electrical conductivities, high temperature resistance, corrosion resistance, and radiation tolerance. It is widely used in many fields such as thermal management, battery electrodes, and the nuclear industry. The carbon content is an important factor that limits the applications of natural graphite minerals, but the impurities are difficult to remove from high-grade graphite minerals. This review discusses the types of natural graphite and mineral resources, followed by a discussion of traditional graphite purification processes and new methods to obtain high-purity graphite. Recent research on the development of natural graphite for use in thermal management, battery electrodes and the nuclear industry are summarized and the future applications of natural graphite are discussed.
2023, 38(1): 96-110.
doi: 10.1016/S1872-5805(23)60715-2
摘要:
树脂炭具有良好的力学、电学以及热物理性能，是广泛应用于航空、航天、能源等领域的结构功能一体化材料。树脂固有的分子结构特性导致树脂炭难石墨化，限制了树脂炭的广泛应用。本文综述了近年来改性树脂炭石墨化及应用的研究进展，系统介绍了催化剂、碳纳米材料、易石墨化共炭化剂三类树脂改性剂，可提高树脂炭的石墨化炭含量并降低其石墨化温度。其中催化剂和碳纳米材料改性剂方面的研究较多，催化剂改性剂在较低温度下（低于1400 °C）便能使树脂炭的石墨化度达74%，而碳纳米材料改性剂需要在2000 °C以上才能较明显地提高树脂炭的石墨化度。相比前两种改性剂，易石墨化的共炭化改性剂不仅能提高树脂炭的石墨化度，还能提高树脂的残炭率。在应用方面，提高树脂炭的石墨化度能提高炭/炭复合材料的导热和导电性能，也能提高超级电容器材料和二次电池电极材料的导电性能、倍率性能和功率密度。最后探讨了改性树脂炭的石墨化及应用面临的挑战和发展方向。
树脂炭具有良好的力学、电学以及热物理性能，是广泛应用于航空、航天、能源等领域的结构功能一体化材料。树脂固有的分子结构特性导致树脂炭难石墨化，限制了树脂炭的广泛应用。本文综述了近年来改性树脂炭石墨化及应用的研究进展，系统介绍了催化剂、碳纳米材料、易石墨化共炭化剂三类树脂改性剂，可提高树脂炭的石墨化炭含量并降低其石墨化温度。其中催化剂和碳纳米材料改性剂方面的研究较多，催化剂改性剂在较低温度下（低于1400 °C）便能使树脂炭的石墨化度达74%，而碳纳米材料改性剂需要在2000 °C以上才能较明显地提高树脂炭的石墨化度。相比前两种改性剂，易石墨化的共炭化改性剂不仅能提高树脂炭的石墨化度，还能提高树脂的残炭率。在应用方面，提高树脂炭的石墨化度能提高炭/炭复合材料的导热和导电性能，也能提高超级电容器材料和二次电池电极材料的导电性能、倍率性能和功率密度。最后探讨了改性树脂炭的石墨化及应用面临的挑战和发展方向。
2023, 38(1): 111-129.
doi: 10.1016/S1872-5805(23)60703-6
摘要:
High-performance electromagnetic wave absorbing materials (EWAMs) are expected to solve electromagnetic wave radiation problems in both the military and civil fields. The desired features of EWAMs include strong absorption over a broad bandwidth, low density, thinness, oxidation resistance, wear resistance, ability to withstand high-temperatures and high strength. Carbon-based materials, including nanostructures and composites, are attractive alternatives to EWAMs because of their unique structures and properties. We summarize recent achievements in carbon-based EWAMs, including different dimensional (0D, 1D, 2D and 3D) carbon nanostructures and various types of carbon composites (dielectric/carbon, magnetic/carbon) and hybrids. The factors affecting the absorption of electromagnetic microwaves include electrical conductivity (σ), permittivity (ε) and permeability (μ) are discussed based on the electromagnetic microwave absorption mechanisms. Representative carbon-based EWAMs and the corresponding mechanisms of improving their electromagnetic microwave absorption are highlighted and analyzed. Strategies for the modification of carbon-based EWAMs are summarized and research trends are proposed.
High-performance electromagnetic wave absorbing materials (EWAMs) are expected to solve electromagnetic wave radiation problems in both the military and civil fields. The desired features of EWAMs include strong absorption over a broad bandwidth, low density, thinness, oxidation resistance, wear resistance, ability to withstand high-temperatures and high strength. Carbon-based materials, including nanostructures and composites, are attractive alternatives to EWAMs because of their unique structures and properties. We summarize recent achievements in carbon-based EWAMs, including different dimensional (0D, 1D, 2D and 3D) carbon nanostructures and various types of carbon composites (dielectric/carbon, magnetic/carbon) and hybrids. The factors affecting the absorption of electromagnetic microwaves include electrical conductivity (σ), permittivity (ε) and permeability (μ) are discussed based on the electromagnetic microwave absorption mechanisms. Representative carbon-based EWAMs and the corresponding mechanisms of improving their electromagnetic microwave absorption are highlighted and analyzed. Strategies for the modification of carbon-based EWAMs are summarized and research trends are proposed.
2023, 38(1): 130-142.
doi: 10.1016/S1872-5805(23)60716-4
摘要:
氟化碳（CFx）是一种由碳质材料（ 如石墨、 石墨烯、碳纳米管等不同化学结构的炭材料）和氟化试剂在一定条件下发生氟化反应而形成的具有C―F键的碳衍生物，由于多样的碳骨架和可控的极性C―F键，使其具有化学稳定性、带隙可调性以及超疏水性等多种优异性能，是新型碳基材料研究热点之一。本文以氟化碳材料的结构和性质为基础，分别从化学能源、摩擦润滑和半导体等领域的应用综述了近年来我国氟化碳材料的基础研究现状和发展趋势。同时，还介绍了我国氟化碳材料的产业化进程，指出目前在民用领域受限的主要原因，提出了当前氟化碳在不同应用领域存在的问题和未来发展机遇，为氟化碳材料的进一步扩大生产和实际应用提供方向。
氟化碳（CFx）是一种由碳质材料（ 如石墨、 石墨烯、碳纳米管等不同化学结构的炭材料）和氟化试剂在一定条件下发生氟化反应而形成的具有C―F键的碳衍生物，由于多样的碳骨架和可控的极性C―F键，使其具有化学稳定性、带隙可调性以及超疏水性等多种优异性能，是新型碳基材料研究热点之一。本文以氟化碳材料的结构和性质为基础，分别从化学能源、摩擦润滑和半导体等领域的应用综述了近年来我国氟化碳材料的基础研究现状和发展趋势。同时，还介绍了我国氟化碳材料的产业化进程，指出目前在民用领域受限的主要原因，提出了当前氟化碳在不同应用领域存在的问题和未来发展机遇，为氟化碳材料的进一步扩大生产和实际应用提供方向。
2023, 38(1): 143-153.
doi: 10.1016/S1872-5805(22)60615-2
摘要:
Hollow porous carbon fibers for Li-S battery electrodes were prepared by the KOH activation of carbon prepared from hollow polyacrylonitrile fibers. The fibers had a high specific surface area of 2 491 m2·g−1, a large pore volume of 1.22 cm3·g−1 and an initial specific capacity of 330 mAh·g−1 at a current density of 1 C. To improve their electrochemical performance, the fibers were modified by treatment with hydrazine hydrate to prepare nitrogen-doped hollow porous carbon fibers with a specific surface area of 1 690 m2·g−1, a pore volume of 0.84 cm3·g−1 and a high nitrogen content of 8.81 at%. Because of the increased polarity and adsorption capacity produced by the nitrogen doping, the initial specific capacity of the fibers was increased to 420 mAh·g−1 at a current density of 1 C.
Hollow porous carbon fibers for Li-S battery electrodes were prepared by the KOH activation of carbon prepared from hollow polyacrylonitrile fibers. The fibers had a high specific surface area of 2 491 m2·g−1, a large pore volume of 1.22 cm3·g−1 and an initial specific capacity of 330 mAh·g−1 at a current density of 1 C. To improve their electrochemical performance, the fibers were modified by treatment with hydrazine hydrate to prepare nitrogen-doped hollow porous carbon fibers with a specific surface area of 1 690 m2·g−1, a pore volume of 0.84 cm3·g−1 and a high nitrogen content of 8.81 at%. Because of the increased polarity and adsorption capacity produced by the nitrogen doping, the initial specific capacity of the fibers was increased to 420 mAh·g−1 at a current density of 1 C.
2023, 38(1): 154-161.
doi: 10.1016/S1872-5805(22)60649-8
摘要:
Metal-nitrogen carbon catalysts have received great attention in the field of gas-evolving electrocatalysis due to their high activity, large specific surface area and efficient gas diffusion paths. A solution of porphyrin iron, g-C3N4 and polyacrylonitrile in N,N-dimethylformamide was sonicated and electrospun into doped polyacrylonitrile nanofibers (NFs), and the NFs were then stabilized and carbonized at 900 °C to prepare Fe-N/CNF catalyst for oxygen reduction reaction (ORR). It was found that the addition of g-C3N4 to the electrospinning precursor led to the formation of abundant Fe-N species in Fe3+ and Fe2+ valence states, while Fe3C nanoparticles were formed without adding g-C3N4. Compared to Fe3C/CNF prepared without g-C3N4, the Fe-N/CNF catalyst presents an 4e− improved oxygen reduction reaction activity in both alkaline and acidic media. Furthermore, as a cathode in Zn-air batteries, the Fe-N/CNF catalyst exhibits high performance with an open-circuit voltage of 1.49 V, a power density of 146 mW cm−2 and a specific capacity of 703 mAh g−1. This work suggests a way to prepare metal-nitrogen-carbon catalysts for energy-related electrocatalytic applications.
Metal-nitrogen carbon catalysts have received great attention in the field of gas-evolving electrocatalysis due to their high activity, large specific surface area and efficient gas diffusion paths. A solution of porphyrin iron, g-C3N4 and polyacrylonitrile in N,N-dimethylformamide was sonicated and electrospun into doped polyacrylonitrile nanofibers (NFs), and the NFs were then stabilized and carbonized at 900 °C to prepare Fe-N/CNF catalyst for oxygen reduction reaction (ORR). It was found that the addition of g-C3N4 to the electrospinning precursor led to the formation of abundant Fe-N species in Fe3+ and Fe2+ valence states, while Fe3C nanoparticles were formed without adding g-C3N4. Compared to Fe3C/CNF prepared without g-C3N4, the Fe-N/CNF catalyst presents an 4e− improved oxygen reduction reaction activity in both alkaline and acidic media. Furthermore, as a cathode in Zn-air batteries, the Fe-N/CNF catalyst exhibits high performance with an open-circuit voltage of 1.49 V, a power density of 146 mW cm−2 and a specific capacity of 703 mAh g−1. This work suggests a way to prepare metal-nitrogen-carbon catalysts for energy-related electrocatalytic applications.
2023, 38(1): 162-172.
doi: 10.1016/S1872-5805(22)60621-8
摘要:
基于低温溶剂法从大宗农林废弃物玉米芯中提取的纤维素，耦合具有优异吸光性能的碳纳米管(CNTs)，构筑复合纤维素水凝胶(CNTs-CH)，利用纤维素凝胶的高保水性、可降解性，以及碳纳米管的高效光热转换能力、优良的力学性能和生物相容性，将其用于太阳能驱动界面水蒸发净化领域。考察了吸光材料CNTs的不同添加量对CNTs-CH复合水凝胶的太阳能吸收率、机械性能及界面光热水蒸发效率的影响。最优条件下，CNTs添加质量百分数仅需0.2%，此CNTs-CH复合纤维素水凝胶的平均蒸发速率可达到~1.52 kg m−2 h−1，太阳能-蒸汽转换效率约为92%；在海水中连续蒸发8 h，蒸发速率可保持在1.37 kg m−2 h−1左右，且无积盐现象，净化水质远高于世界卫生组织和美国环境保护署对饮用水的标准，说明CNTs-CH抗盐性能较强。此外，CNTs-CH水凝胶在强酸/碱性水溶液体系、染料废水和重金属离子污染水体中的蒸发速率可维持为1.30~1.40 kg m−2 h−1，太阳能-蒸汽效率可达到80%~86%，对污染物及盐分截留率高达99.9%，蒸发效果稳定，说明CNTs-CH光热蒸发器在海水淡化和工业废水净化回用领域有广阔的应用前景。
基于低温溶剂法从大宗农林废弃物玉米芯中提取的纤维素，耦合具有优异吸光性能的碳纳米管(CNTs)，构筑复合纤维素水凝胶(CNTs-CH)，利用纤维素凝胶的高保水性、可降解性，以及碳纳米管的高效光热转换能力、优良的力学性能和生物相容性，将其用于太阳能驱动界面水蒸发净化领域。考察了吸光材料CNTs的不同添加量对CNTs-CH复合水凝胶的太阳能吸收率、机械性能及界面光热水蒸发效率的影响。最优条件下，CNTs添加质量百分数仅需0.2%，此CNTs-CH复合纤维素水凝胶的平均蒸发速率可达到~1.52 kg m−2 h−1，太阳能-蒸汽转换效率约为92%；在海水中连续蒸发8 h，蒸发速率可保持在1.37 kg m−2 h−1左右，且无积盐现象，净化水质远高于世界卫生组织和美国环境保护署对饮用水的标准，说明CNTs-CH抗盐性能较强。此外，CNTs-CH水凝胶在强酸/碱性水溶液体系、染料废水和重金属离子污染水体中的蒸发速率可维持为1.30~1.40 kg m−2 h−1，太阳能-蒸汽效率可达到80%~86%，对污染物及盐分截留率高达99.9%，蒸发效果稳定，说明CNTs-CH光热蒸发器在海水淡化和工业废水净化回用领域有广阔的应用前景。
2023, 38(1): 173-189.
doi: 10.1016/S1872-5805(22)60606-1
摘要:
An innovative and efficient method for preparation of mesocarbon microbeads (MCMBs) was developed based on the dripping behavior and rheological properties of molten pitch during melt-spinning, where a string of beads was formed after the pitch was extruded from spinnerets and dropped into a receiving solvent (tetrohydrofuran or water). The pitch droplets were first carbonized, then activated by KOH or graphitized at 2800 °C to prepare A-MCMBs or G-MCMBs, respectively, and these were respectively used as the electrode materials for electric double layer capacitors (EDLCs) and lithium-ion batteries (LIBs). Results showed that both MCMB-W prepared using water as the receiving solvent and MCMB-T prepared using tetrohydrofuran as the receiving solvent had a spherical shape with sizes of 1-2 μm. A-MCMB-T had a high specific surface area (1 391 m2 g−1), micropore volume (0.55 cm3 g−1) and mesopore volume (0.24 cm3 g−1), with a 30% higher specific capacitance than an activated mesophase carbon prepared under the same conditions, and its capacitance retention was significantly improved when it was used as an electrode material for EDLCs. G-MCMB-T had a high degree of graphitization (0.895) and when it was used as an electrode material for LIBs it had a high specific capacity of 353.5 mAh g−1 after 100 cycles at 100 mA g−1. This work reports a new preparation method for MCMBs, which could be used to prepare energy storage materials.
An innovative and efficient method for preparation of mesocarbon microbeads (MCMBs) was developed based on the dripping behavior and rheological properties of molten pitch during melt-spinning, where a string of beads was formed after the pitch was extruded from spinnerets and dropped into a receiving solvent (tetrohydrofuran or water). The pitch droplets were first carbonized, then activated by KOH or graphitized at 2800 °C to prepare A-MCMBs or G-MCMBs, respectively, and these were respectively used as the electrode materials for electric double layer capacitors (EDLCs) and lithium-ion batteries (LIBs). Results showed that both MCMB-W prepared using water as the receiving solvent and MCMB-T prepared using tetrohydrofuran as the receiving solvent had a spherical shape with sizes of 1-2 μm. A-MCMB-T had a high specific surface area (1 391 m2 g−1), micropore volume (0.55 cm3 g−1) and mesopore volume (0.24 cm3 g−1), with a 30% higher specific capacitance than an activated mesophase carbon prepared under the same conditions, and its capacitance retention was significantly improved when it was used as an electrode material for EDLCs. G-MCMB-T had a high degree of graphitization (0.895) and when it was used as an electrode material for LIBs it had a high specific capacity of 353.5 mAh g−1 after 100 cycles at 100 mA g−1. This work reports a new preparation method for MCMBs, which could be used to prepare energy storage materials.
2023, 38(1): 190-199.
doi: 10.1016/S1872-5805(22)60596-1
摘要:
Li-Se batteries have risen to prominence as promising lithium-ion batteries thanks to their ultrahigh volumetric energy density and the high electrical conductivity of Se. However, the use of Li-Se batteries is limited not only by the large volume expansion and dissolution of polyselenides in the cathodes during cycling, but also the low selenium loading. A highly effective and currently feasible approach to simultaneously tackle these problems is to position the selenium in a carbon matrix with a sufficient pore volume to accommodate the expansion while increasing the interfacial interaction between the selenium and carbon. We have synthesized a novel cathode material (Se@HPC) for Li-Se batteries of a honeycomb 3D porous carbon derived from a tartrate salt, that was impregnated with Se to produce Se-C bonds. The pore volume of the honeycomb 3D porous carbon was as high as 1.794 cm3 g−1, which allowed 65 wt% selenium to be uniformly encapsulated. Moreover, the strong chemical bonds between selenium and carbon stabilize the selenium, thus inhibiting its huge volume expansion and the dissolution of polyselenides, and promoting charge transfer during cycling. As expected, a Se@HCP cathode has excellent cyclability and a good rate performance. After 200 cycles at 0.2 C, its specific capacity remains at 561 mA h g−1, 83% of the theoretical value, and decays by only 0.058% per cycle. It also has a large capacity of 472.8 mA h g−1 under a high current density of 5 C.
Li-Se batteries have risen to prominence as promising lithium-ion batteries thanks to their ultrahigh volumetric energy density and the high electrical conductivity of Se. However, the use of Li-Se batteries is limited not only by the large volume expansion and dissolution of polyselenides in the cathodes during cycling, but also the low selenium loading. A highly effective and currently feasible approach to simultaneously tackle these problems is to position the selenium in a carbon matrix with a sufficient pore volume to accommodate the expansion while increasing the interfacial interaction between the selenium and carbon. We have synthesized a novel cathode material (Se@HPC) for Li-Se batteries of a honeycomb 3D porous carbon derived from a tartrate salt, that was impregnated with Se to produce Se-C bonds. The pore volume of the honeycomb 3D porous carbon was as high as 1.794 cm3 g−1, which allowed 65 wt% selenium to be uniformly encapsulated. Moreover, the strong chemical bonds between selenium and carbon stabilize the selenium, thus inhibiting its huge volume expansion and the dissolution of polyselenides, and promoting charge transfer during cycling. As expected, a Se@HCP cathode has excellent cyclability and a good rate performance. After 200 cycles at 0.2 C, its specific capacity remains at 561 mA h g−1, 83% of the theoretical value, and decays by only 0.058% per cycle. It also has a large capacity of 472.8 mA h g−1 under a high current density of 5 C.
2023, 38(1): 200-210.
doi: 10.1016/S1872-5805(22)60609-7
摘要:
Carbon-based catalysts for the oxygen reduction reaction (ORR) are considered potential substitutes for the expensive platinum-based catalysts. Recently, transition metal and nitrogen co-doped carbon materials (M-N-C) have attracted much attention from researchers due to their low cost and excellent activity. A cobalt- and nitrogen-co-doped porous carbon material (Co-N@CNT-C800) was prepared by the simple one-step pyrolysis of a star fruit-like MOF hybrid (ZIF-8@ZIF-67) at 800 °C. It consisted of CNTs with substantial Co and N co-doping and had a large surface area (428 m2·g−1). It had an excellent half-wave potential and good current density in alkaline media in the ORR with values of 0.841 V and 5.07 mA·cm−2, respectively. Compared with commercial Pt/C materials it also had excellent electrochemical stability and methanol tolerance. This research provides an effective way to fabricate low cost, high activity electrocatalysts for use in energy conversion.
Carbon-based catalysts for the oxygen reduction reaction (ORR) are considered potential substitutes for the expensive platinum-based catalysts. Recently, transition metal and nitrogen co-doped carbon materials (M-N-C) have attracted much attention from researchers due to their low cost and excellent activity. A cobalt- and nitrogen-co-doped porous carbon material (Co-N@CNT-C800) was prepared by the simple one-step pyrolysis of a star fruit-like MOF hybrid (ZIF-8@ZIF-67) at 800 °C. It consisted of CNTs with substantial Co and N co-doping and had a large surface area (428 m2·g−1). It had an excellent half-wave potential and good current density in alkaline media in the ORR with values of 0.841 V and 5.07 mA·cm−2, respectively. Compared with commercial Pt/C materials it also had excellent electrochemical stability and methanol tolerance. This research provides an effective way to fabricate low cost, high activity electrocatalysts for use in energy conversion.
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：
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：
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：
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：
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：
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：
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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