留言板

尊敬的读者、作者、审稿人, 关于本刊的投稿、审稿、编辑和出版的任何问题, 您可以本页添加留言。我们将尽快给您答复。谢谢您的支持!

姓名
邮箱
手机号码
标题
留言内容
验证码

优先发表

优先发表栏目展示本刊经同行评议确定正式录用的文章,这些文章目前处在编校过程,尚未确定卷期及页码,但可以根据DOI进行引用。
显示方式:
综合评述
低阶煤基炭材料研究进展
宋文革, 曾红久, 王斌, 黄显虹, 李晓明, 孙国华
, doi: 10.1016/S1872-5805(24)60872-3
摘要(46) HTML(23) PDF(2)
摘要:
低阶煤由于具有储量丰富、碳含量高、芳烃结构易调整等特点,已被广泛用于制备高性能炭材料的理想前驱体。为进一步实现低阶煤高值化利用与高性能煤基炭材料的可控制备,本文综述了低阶煤在炭材料制备领域的最新研究进展。首先全面分析了低阶煤的物理化学特性,并通过代表性的文献阐述了低阶煤及其衍生物在制备储能炭材料、吸附活性炭及纳米炭材料的方法和改性策略,及煤基炭材料的应用性能。其次,本文深入解析了低阶煤中灰分、伴生杂原子的存在对煤基炭材料应用性能的潜在影响,为高性能煤基炭材料的工艺优化与可控制备提交依据。最后,本文对低阶煤基炭材料的未来所面临的挑战与机遇进行了展望,强调在新型制备技术探索、材料性能深度挖掘以及能源存储、环境净化、催化反应等前沿领域的应用创新的重要性。综上所述,本文综述不仅是对当前研究成果的全面回顾,更是对未来发展趋势的深刻展望,有望为低阶煤基炭材料的结构设计与应用性能优化提供指导。 低阶煤由于具有储量丰富、碳含量高、芳烃结构易调整等特点,已被广泛用于制备高性能炭材料的理想前驱体。为进一步实现低阶煤高值化利用与高性能煤基炭材料的可控制备,本文综述了低阶煤在炭材料制备领域的最新研究进展。首先全面分析了低阶煤的物理化学特性,并通过代表性的文献阐述了低阶煤及其衍生物在制备储能炭材料、吸附活性炭及纳米炭材料的方法和改性策略,及煤基炭材料的应用性能。其次,本文深入解析了低阶煤中灰分、伴生杂原子的存在对煤基炭材料应用性能的潜在影响,为高性能煤基炭材料的工艺优化与可控制备提交依据。最后,本文对低阶煤基炭材料的未来所面临的挑战与机遇进行了展望,强调在新型制备技术探索、材料性能深度挖掘以及能源存储、环境净化、催化反应等前沿领域的应用创新的重要性。综上所述,本文综述不仅是对当前研究成果的全面回顾,更是对未来发展趋势的深刻展望,有望为低阶煤基炭材料的结构设计与应用性能优化提供指导。
A review on the N-doped carbon materials: Preparation, property and an application exemplification for sodium storage
YUAN Ren-lu, HOU Ruo-yang, SHANG Lei, LIU Xue-wei, LI Ang, CHEN Xiao-hong, SONG Huai-he
, doi: 10.1016/S1872-5805(24)60877-2
摘要(31) HTML(13) PDF(3)
摘要:
As a powerful technology, defect engineering by heteroatom doping endows carbon materials with some new functions such as unique electronic structure and high activity, showing a great significance for their structure modulation towards high-performance application. N-doping has been widely investigated due to the similar atom radius with carbon, high electronegativity as well as multiplex configuration. In this review, we mainly summarized the preparation methods and properties of N-doped carbon materials and also discussed their application potential with an exemplification for sodium storage. The in-situ and post-treatment preparation strategies were detailly described. The relationship between N content/configuration and crystallinity, electronic conductivity, wettability, chemical reactivity as well as sodium storage ability was discussed. Meanwhile some related researches of our group were also introduced. This review is expected to provide a powerful guidance for the controlled preparation and structure design of N-doped carbon materials. As a powerful technology, defect engineering by heteroatom doping endows carbon materials with some new functions such as unique electronic structure and high activity, showing a great significance for their structure modulation towards high-performance application. N-doping has been widely investigated due to the similar atom radius with carbon, high electronegativity as well as multiplex configuration. In this review, we mainly summarized the preparation methods and properties of N-doped carbon materials and also discussed their application potential with an exemplification for sodium storage. The in-situ and post-treatment preparation strategies were detailly described. The relationship between N content/configuration and crystallinity, electronic conductivity, wettability, chemical reactivity as well as sodium storage ability was discussed. Meanwhile some related researches of our group were also introduced. This review is expected to provide a powerful guidance for the controlled preparation and structure design of N-doped carbon materials.
Application of metal–organic frameworks and their derivatives for lithium-ion capacitors
ZHAO Sha-sha, ZHANG Xiong, LI Chen, AN Ya-bin, HU Tao, WANG Kai, SUN Xian-zhong, MA Yan-wei
, doi: 10.1016/S1872-5805(24)60873-5
摘要(32) HTML(22) PDF(2)
摘要:
There is an urgent need for lithium-ion capacitors (LICs) that possess both high energy density and high power density to meet the continuously growing energy storage demands. LICs effectively balance the high energy density of traditional batteries with the superior power density and longevity of supercapacitors (SCs). Nevertheless, the development of LICs is still hampered by the challenges of kinetic processes and capacity mismatch between the cathode and anode. Metal-organic frameworks (MOFs) and their derivatives have garnered significant attention owing to their extensive specific surface area, rich pore structures, diverse topologies, and customizable functional sites, making them compelling candidate materials for achieving high-performance LICs. MOF-derived carbons, known for their exceptional electrical conductivity and extensive surface area, provide improved charge storage and rapid ion transport. MOF-derived transition metal oxides contribute to high specific capacities and improved electrochemical stability. Additionally, MOF-derived metal compounds/carbons provide synergistic effects that enhance both the capacitive and faradaic reactions, leading to superior overall performance. This review systematically examines the latest advancements of MOFs and their derivatives in LICs, emphasizing the correlation linking architecture/composition to electrochemical properties, and providing a future outlook to guide further research and technological developments in energy storage. There is an urgent need for lithium-ion capacitors (LICs) that possess both high energy density and high power density to meet the continuously growing energy storage demands. LICs effectively balance the high energy density of traditional batteries with the superior power density and longevity of supercapacitors (SCs). Nevertheless, the development of LICs is still hampered by the challenges of kinetic processes and capacity mismatch between the cathode and anode. Metal-organic frameworks (MOFs) and their derivatives have garnered significant attention owing to their extensive specific surface area, rich pore structures, diverse topologies, and customizable functional sites, making them compelling candidate materials for achieving high-performance LICs. MOF-derived carbons, known for their exceptional electrical conductivity and extensive surface area, provide improved charge storage and rapid ion transport. MOF-derived transition metal oxides contribute to high specific capacities and improved electrochemical stability. Additionally, MOF-derived metal compounds/carbons provide synergistic effects that enhance both the capacitive and faradaic reactions, leading to superior overall performance. This review systematically examines the latest advancements of MOFs and their derivatives in LICs, emphasizing the correlation linking architecture/composition to electrochemical properties, and providing a future outlook to guide further research and technological developments in energy storage.
Research progress on carbon coating of silicon anode in high-performance lithium-ion batteries
XU Ze-yu, SHAO Hai-bo, WANG Jian-ming
, doi: 10.1016/S1872-5805(24)60871-1
摘要(38) HTML(21) PDF(1)
摘要:
In recent years, the rapid growth of energy demand has led to great progress in the development of rechargeable lithium batteries (LIBs). Silicon anode has attracted much attention by virtue of its extremely high theoretical capacity, relatively low Li-insertion voltage and availability of silicon resources. Nevertheless, the violent volume expansion and fragile solid electrolyte interface (SEI) film hinder the commercial application of Si-based anodes. To solve the above issues, Si materials are combined with various carbonaceous materials, which is conducive to enhanced structural stability and optimized interface characteristics. Herein, different carbonaceous materials as 3D protective coatings for Si anodes to buffer mechanical strain and isolate electrolyte are presented in this review. The novel preparation methods for integrating silicon particles with various carbon materials are outlined. However, carbon materials as protective layer still have some disadvantages until now, thus showing the necessity for further modification on protective carbon coatings. Recent developments on the modification of protective carbon shells are focused on. The potential substitute for the 3D carbon coating of Si anodes is suggested. It is expected that this review may help researchers to understand the comprehensive information of Si/C composite anodes and promote their success in the related fields. In recent years, the rapid growth of energy demand has led to great progress in the development of rechargeable lithium batteries (LIBs). Silicon anode has attracted much attention by virtue of its extremely high theoretical capacity, relatively low Li-insertion voltage and availability of silicon resources. Nevertheless, the violent volume expansion and fragile solid electrolyte interface (SEI) film hinder the commercial application of Si-based anodes. To solve the above issues, Si materials are combined with various carbonaceous materials, which is conducive to enhanced structural stability and optimized interface characteristics. Herein, different carbonaceous materials as 3D protective coatings for Si anodes to buffer mechanical strain and isolate electrolyte are presented in this review. The novel preparation methods for integrating silicon particles with various carbon materials are outlined. However, carbon materials as protective layer still have some disadvantages until now, thus showing the necessity for further modification on protective carbon coatings. Recent developments on the modification of protective carbon shells are focused on. The potential substitute for the 3D carbon coating of Si anodes is suggested. It is expected that this review may help researchers to understand the comprehensive information of Si/C composite anodes and promote their success in the related fields.
A review on catalytic preparation of mesophase pitch
MA Zi-hui, YANG Tao, SONG Yan, CHEN Wen-sheng, DUAN Chun-feng, SONG Huai-he, TIAN Xiao-dong, GONG Xiang-jie, LIU Zheng-yang, LIU Zhan-jun
, doi: 10.1016/S1872-5805(24)60862-0
摘要(133) HTML(58) PDF(15)
摘要:
Mesophase pitch, due to its high purity and excellent orientation, is a superior precursor for high-performance carbon materials. However, the preparation of top-notch mesophase pitch faces challenges. Catalytic polycondensation at low temperature is more favorable for synthesizing mesophase pitch, which circumvents the high-temperature free radical reaction of other thermal polycondensation approaches. Besides, the reaction is gentle and could be easily controlled. It has the potential to significantly improve the yield of mesophase pitch and easily introduce the naphthenic characteristics into the molecules, hence, catalytic polycondensation is a preferentially recommended methodology to synthesize highly spinnable mesophase pitch. This paper furnishes a synopsis of the selection pretreatment of raw materials to prepare diverse mesophase pitches, and explains the reaction mechanism and associated research advancements of different catalytic systems in recent years. Ultimately, how to manufacture high-quality mesophase pitch by employing a catalyst-promoter system is summarized and proposed, it is expected to present original concepts and dependable theoretical direction for the design of high-quality pitch molecules in the future. Mesophase pitch, due to its high purity and excellent orientation, is a superior precursor for high-performance carbon materials. However, the preparation of top-notch mesophase pitch faces challenges. Catalytic polycondensation at low temperature is more favorable for synthesizing mesophase pitch, which circumvents the high-temperature free radical reaction of other thermal polycondensation approaches. Besides, the reaction is gentle and could be easily controlled. It has the potential to significantly improve the yield of mesophase pitch and easily introduce the naphthenic characteristics into the molecules, hence, catalytic polycondensation is a preferentially recommended methodology to synthesize highly spinnable mesophase pitch. This paper furnishes a synopsis of the selection pretreatment of raw materials to prepare diverse mesophase pitches, and explains the reaction mechanism and associated research advancements of different catalytic systems in recent years. Ultimately, how to manufacture high-quality mesophase pitch by employing a catalyst-promoter system is summarized and proposed, it is expected to present original concepts and dependable theoretical direction for the design of high-quality pitch molecules in the future.
高比能快充型钠离子电池炭负极:进展与挑战
黎璟泓, 张一波, 贾怡然, 杨晨旭, 褚悦, 张俊, 陶莹, 杨全红
, doi: 10.1016/S1872-5805(24)60870-X
摘要(62) HTML(34) PDF(8)
摘要:
由于具有优异的快充与低温特性,并且钠元素资源丰富、成本低廉,钠离子电池成为下一代非资源限制型高效储能体系的首选。无定形炭材料是钠离子电池实用化进程的关键负极材料,具备较高首次库伦效率、低嵌钠平台、稳定性好等优点。然而,目前无定形炭负极存在平台储钠动力学差以及高平台容量与高平台电位无法兼得的问题,导致钠离子电池的快充性能、能量密度以及安全特性顾此失彼,严重制约了钠离子电池的产业化进程。本文聚焦制约钠离子电池碳负极发展的关键瓶颈,分析了无定形炭平台储钠各基元步骤的动力学行为,从电极-电解液界面和无定形炭微观结构调控两方面梳理了构建高比能快充型钠离子电池的工作进展,并探讨了影响平台储钠动力学与平台电位的关键要素,最后针对钠离子电池碳负极的发展方向与关键挑战进行了简要评述和展望,以期推动实用型钠离子电池碳负极材料的发展。 由于具有优异的快充与低温特性,并且钠元素资源丰富、成本低廉,钠离子电池成为下一代非资源限制型高效储能体系的首选。无定形炭材料是钠离子电池实用化进程的关键负极材料,具备较高首次库伦效率、低嵌钠平台、稳定性好等优点。然而,目前无定形炭负极存在平台储钠动力学差以及高平台容量与高平台电位无法兼得的问题,导致钠离子电池的快充性能、能量密度以及安全特性顾此失彼,严重制约了钠离子电池的产业化进程。本文聚焦制约钠离子电池碳负极发展的关键瓶颈,分析了无定形炭平台储钠各基元步骤的动力学行为,从电极-电解液界面和无定形炭微观结构调控两方面梳理了构建高比能快充型钠离子电池的工作进展,并探讨了影响平台储钠动力学与平台电位的关键要素,最后针对钠离子电池碳负极的发展方向与关键挑战进行了简要评述和展望,以期推动实用型钠离子电池碳负极材料的发展。
炭气凝胶在光热转换领域的研究进展
郎延亭, 何宇, 宋怀河, 易黎明, 邓海军, 陈晓红
, doi: 10.1016/S1872-5805(24)60865-6
摘要(50) HTML(50) PDF(7)
摘要:
光热转换是指将太阳能转换成热能,能够实现利用太阳能这种清洁可再生资源缓解能源匮乏。炭气凝胶材料具有高度发达的孔隙结构、优异的光捕获能力和高光热转换效率等优点,是当下光热转换领域研究热点。本文首先简单概述了不同光热材料的光热转换原理,然后从炭气凝胶种类入手分别讨论了石墨烯气凝胶、碳纳米管气凝胶、生物质基炭气凝胶和聚合物基炭气凝胶几种炭气凝胶作为光热材料的研究进展,最后介绍了炭气凝胶作为光热材料在太阳能水蒸发、热能储存、光热催化、光热治疗和光热除冰等方面的应用。 光热转换是指将太阳能转换成热能,能够实现利用太阳能这种清洁可再生资源缓解能源匮乏。炭气凝胶材料具有高度发达的孔隙结构、优异的光捕获能力和高光热转换效率等优点,是当下光热转换领域研究热点。本文首先简单概述了不同光热材料的光热转换原理,然后从炭气凝胶种类入手分别讨论了石墨烯气凝胶、碳纳米管气凝胶、生物质基炭气凝胶和聚合物基炭气凝胶几种炭气凝胶作为光热材料的研究进展,最后介绍了炭气凝胶作为光热材料在太阳能水蒸发、热能储存、光热催化、光热治疗和光热除冰等方面的应用。
研究论文
In-situ thermal Raman mapping and stress analysis of CNT/CF/epoxy interfaces
HE Jing-zong, CHEN Shi, MA Zheng-kun, LU Yong-gen, WU Qi-lin
, doi: 10.1016/S1872-5805(24)60874-7
摘要(44) HTML(13) PDF(2)
摘要:
A study of the interfacial behavior and internal thermal stress distribution in fiber-reinforced composites is essential to assess their performance and reliability. CNT/carbon fiber (CF) hybrid fibers were constructed using electrophoretic deposition. The interfacial properties of CF/epoxy and CNT/CF/epoxy composites were statistically investigated and compared using in-situ thermal Raman mapping by dispersing CNTs as a Raman sensing medium (CNTR) in a resin. The associated local thermal stress changes can be simulated by capturing the G' band position distribution of CNTR in the epoxy at different temperatures. It was found that the G' band shifted to lower positions with increasing temperature, reaching a maximum difference of 2.43 cm−1 at 100 °C. The interfacial bonding between CNT/CF and the matrix and the stress distribution and changes during heat treatment (20–100 °C) were investigated in detail. The study is important for studying thermal stress in fiber-reinforced composites by in-situ thermal Raman mapping technology. A study of the interfacial behavior and internal thermal stress distribution in fiber-reinforced composites is essential to assess their performance and reliability. CNT/carbon fiber (CF) hybrid fibers were constructed using electrophoretic deposition. The interfacial properties of CF/epoxy and CNT/CF/epoxy composites were statistically investigated and compared using in-situ thermal Raman mapping by dispersing CNTs as a Raman sensing medium (CNTR) in a resin. The associated local thermal stress changes can be simulated by capturing the G' band position distribution of CNTR in the epoxy at different temperatures. It was found that the G' band shifted to lower positions with increasing temperature, reaching a maximum difference of 2.43 cm−1 at 100 °C. The interfacial bonding between CNT/CF and the matrix and the stress distribution and changes during heat treatment (20–100 °C) were investigated in detail. The study is important for studying thermal stress in fiber-reinforced composites by in-situ thermal Raman mapping technology.
A porous FeOx, N co-doped carbon material as efficient catalyst toward oxygen reduction reaction in both alkaline and acidic electrolytes
GAO Jian, WANG Xinyao, MENG Lingxin, YIN Zhen, MA Na, TAN Xiaoyao, ZHANG Peng
, doi: 10.1016/S1872-5805(24)60876-0
摘要(20) HTML(6) PDF(1)
摘要:
To replace the precious metal ORR (oxygen reduction reaction) electrocatalysts, many TM (transition metal) and N-doped carbon composites have been proposed in last decade and acquire a rapid development as the promising non-precious metal catalysts. Herein, Ketjenblack carbon (KB) is adopted as the precursor and fully mixed with the polymeric ionic liquid (PIL) of [Hvim]NO3 and Fe(NO3)3. This mixture is thermally calcinated into a porous Fe, N co-doped carbon material denoted as the FeOx-N/C at 900 °C. Due to that the PIL of [Hvim]NO3 can strongly combine and disperse Fe3+ ions, and NO3 will thermally pyrolysis to form the porous structure, the FeOx-N/C catalyst displays high electrocatalytic activity toward ORR in both 0.1 M KOH and 0.5 M H2SO4 electrolytes. Subsequently, the FeOx-N/C is used as the catalyst to assemble a zinc-air battery (ZAB) exhibiting a peak power density of 185 mW·cm−2. Consequently, the superior electrocatalytic activity, wide pH range, and facile preparation approach jointly make the FeOx-N/C a promising electrocatalyst for the fuel cell and metal-air battery in the future. To replace the precious metal ORR (oxygen reduction reaction) electrocatalysts, many TM (transition metal) and N-doped carbon composites have been proposed in last decade and acquire a rapid development as the promising non-precious metal catalysts. Herein, Ketjenblack carbon (KB) is adopted as the precursor and fully mixed with the polymeric ionic liquid (PIL) of [Hvim]NO3 and Fe(NO3)3. This mixture is thermally calcinated into a porous Fe, N co-doped carbon material denoted as the FeOx-N/C at 900 °C. Due to that the PIL of [Hvim]NO3 can strongly combine and disperse Fe3+ ions, and NO3 will thermally pyrolysis to form the porous structure, the FeOx-N/C catalyst displays high electrocatalytic activity toward ORR in both 0.1 M KOH and 0.5 M H2SO4 electrolytes. Subsequently, the FeOx-N/C is used as the catalyst to assemble a zinc-air battery (ZAB) exhibiting a peak power density of 185 mW·cm−2. Consequently, the superior electrocatalytic activity, wide pH range, and facile preparation approach jointly make the FeOx-N/C a promising electrocatalyst for the fuel cell and metal-air battery in the future.
Preparation of high-performance synthetic pitch from N/Cl-bearing aromatic hydrocarbons
ZHANG Yu-kun, LIN Xiong-chao, GAO Hong-feng, XI Wen-shuai, WANG Cai-hong, WANG Yong-gang
, doi: 10.1016/S1872-5805(24)60864-4
摘要(42) HTML(15) PDF(4)
摘要:
Preparation of synthetic pitch using aromatic monomers could easily regulate the oriented structure at molecular level, which is conducive to the fabrication of high-performance carbon fiber. In this study, the isotopically synthetic pitch was successfully prepared using N- and Cl-bearing aromatic hydrocarbon precursors by halogen-induced method. The halogenation- enhanced synthetic process was systematically verified by investigating the structural variation under different synthetic conditions; and the reaction mechanism was thoroughly probed for preparation of high-performance carbon fibers. The result shows that the pyridine N in quinoline has strong electrophilic function, which is found be the effective active site to induce the polymerization reaction by coupling with Cl-bearing aromatic hydrocarbons. The mutual reaction among such free radicals would cause strong homopolymerization and oligomerization. Higher synthesis temperature and longer retention time are beneficial to increase the polymerization degree and thus elevate the softening point of synthetic pitch. Moreover, linear molecular structure was formed by the designated Cl and methyl substitution process, which was available for the preparation of highly spinnable pitch. Consequently, a high-quality spinnable pitch with a softening point of 258.6 °C and as-prepared carbon fiber with a tensile strength of 1163.82 MPa was obtained. This study is expected to provide a relatively simple and safe method for the preparation of high-quality spinnable pitch. Preparation of synthetic pitch using aromatic monomers could easily regulate the oriented structure at molecular level, which is conducive to the fabrication of high-performance carbon fiber. In this study, the isotopically synthetic pitch was successfully prepared using N- and Cl-bearing aromatic hydrocarbon precursors by halogen-induced method. The halogenation- enhanced synthetic process was systematically verified by investigating the structural variation under different synthetic conditions; and the reaction mechanism was thoroughly probed for preparation of high-performance carbon fibers. The result shows that the pyridine N in quinoline has strong electrophilic function, which is found be the effective active site to induce the polymerization reaction by coupling with Cl-bearing aromatic hydrocarbons. The mutual reaction among such free radicals would cause strong homopolymerization and oligomerization. Higher synthesis temperature and longer retention time are beneficial to increase the polymerization degree and thus elevate the softening point of synthetic pitch. Moreover, linear molecular structure was formed by the designated Cl and methyl substitution process, which was available for the preparation of highly spinnable pitch. Consequently, a high-quality spinnable pitch with a softening point of 258.6 °C and as-prepared carbon fiber with a tensile strength of 1163.82 MPa was obtained. This study is expected to provide a relatively simple and safe method for the preparation of high-quality spinnable pitch.
Unraveling the Potassium Storage Performance of Carbon Nanosheets Derived from Heavy Oils
ZHAO Qing-shan, LIU Qin-lian, LI Yi-wen, JI Tian, YAO Yu-yue, ZHAO Yi-kun, DENG Wei, HU Han, WU Ming-bo
, doi: 10.1016/S1872-5805(24)60875-9
摘要(20) HTML(7) PDF(4)
摘要:
As by-products of petroleum refining, heavy oils are characterized by high content of carbon, low cost, and abundant tunability, endowing them as competitive precursors for constructing anodes for potassium ion batteries (PIBs). However, the correlation between heavy oil composition and potassium storage performance remains unclear. In this study, by employing heavy oils with distinct group compositions as carbon sources, namely fluid catalytic cracking slurry (FCCs), petroleum asphalt (PA), and deoiled asphalt (DOA), three carbon nanosheets (CNS) were prepared through a molten salt method as anodes for PIBs. The four-component composition of heavy oils can effectively tailor the lamellar thicknesses, sp3-C/sp2-C ratios, and defect levels, thereby affecting the potassium storage performance. Notably, with a high content of aromatic hydrocarbons and moderate heavy component moieties, the FCCs-derived carbon nanosheets (CNS-FCCs) exhibits a smaller layer thickness, enlarged interlayer spacing (0.372 nm), and increased folding defects, leading to promoted charge/ion transfer, more potassium storage sites, and enhanced reaction kinetics. The CNS-FCCs delivers a remarkable K+ storage capacity (248.7 mAh g−1 after 100 cycles at 0.1 A g−1), long cycle lifespan (190.8 mAh g−1 after 800 cycles at 1.0 A g−1), and excellent rate capability, lying among the first echelons. This work sheds light on the influence mechanism of heavy oil composition on carbon structure and electrochemical performance, providing guidance for the design and development of advanced heavy oil-derived carbon electrodes for PIBs. As by-products of petroleum refining, heavy oils are characterized by high content of carbon, low cost, and abundant tunability, endowing them as competitive precursors for constructing anodes for potassium ion batteries (PIBs). However, the correlation between heavy oil composition and potassium storage performance remains unclear. In this study, by employing heavy oils with distinct group compositions as carbon sources, namely fluid catalytic cracking slurry (FCCs), petroleum asphalt (PA), and deoiled asphalt (DOA), three carbon nanosheets (CNS) were prepared through a molten salt method as anodes for PIBs. The four-component composition of heavy oils can effectively tailor the lamellar thicknesses, sp3-C/sp2-C ratios, and defect levels, thereby affecting the potassium storage performance. Notably, with a high content of aromatic hydrocarbons and moderate heavy component moieties, the FCCs-derived carbon nanosheets (CNS-FCCs) exhibits a smaller layer thickness, enlarged interlayer spacing (0.372 nm), and increased folding defects, leading to promoted charge/ion transfer, more potassium storage sites, and enhanced reaction kinetics. The CNS-FCCs delivers a remarkable K+ storage capacity (248.7 mAh g−1 after 100 cycles at 0.1 A g−1), long cycle lifespan (190.8 mAh g−1 after 800 cycles at 1.0 A g−1), and excellent rate capability, lying among the first echelons. This work sheds light on the influence mechanism of heavy oil composition on carbon structure and electrochemical performance, providing guidance for the design and development of advanced heavy oil-derived carbon electrodes for PIBs.
Formation of mesophase microbeads from bulk mesophase pitch induced by fullerene
CHEN Wen-sheng, LIU Lan-tao, WANG Zheng, DUAN Chun-feng, ZHANG Xing-wei, MA Zhao-kun, CHEN Xiao-hong, SONG Huai-he
, doi: 10.1016/S1872-5805(24)60866-8
摘要(58) HTML(26) PDF(1)
摘要:
The controllable transformation of mesophase pitch (MP) exhibits great practical significance for studying the formation mechanism and application of MP. This work accomplished the reversible transformation of the mesophase morphology from bulk to spherical type by heat-treating naphthalene-based mesophase pitch (NMP) uniformly dispersed with fullerenes (C60). The effects of C60 loading and reaction temperature on the morphological transformation of mesophase are investigated by polarizing microscope and scanning electron microscopy. The physical induction of NMP by C60 was characterized by thermogravimetric analysis, Fourier transform infrared spectroscopy, X-ray diffractometry and Raman spectroscopy. The results show that the bulk type of NMP can be converted to spherical type at 300–320 °C heat treatment temperature with the addition of 5% C60, and the size of mesophase microbeads increases with increasing temperature. Furthermore, a model is established to explain the unique induction effect of C60 in the reversible transformation process. This work makes the morphological transformation of MP controllable, which provides a new idea for the subsequent research on MP morphology. The controllable transformation of mesophase pitch (MP) exhibits great practical significance for studying the formation mechanism and application of MP. This work accomplished the reversible transformation of the mesophase morphology from bulk to spherical type by heat-treating naphthalene-based mesophase pitch (NMP) uniformly dispersed with fullerenes (C60). The effects of C60 loading and reaction temperature on the morphological transformation of mesophase are investigated by polarizing microscope and scanning electron microscopy. The physical induction of NMP by C60 was characterized by thermogravimetric analysis, Fourier transform infrared spectroscopy, X-ray diffractometry and Raman spectroscopy. The results show that the bulk type of NMP can be converted to spherical type at 300–320 °C heat treatment temperature with the addition of 5% C60, and the size of mesophase microbeads increases with increasing temperature. Furthermore, a model is established to explain the unique induction effect of C60 in the reversible transformation process. This work makes the morphological transformation of MP controllable, which provides a new idea for the subsequent research on MP morphology.
高石墨化度多孔炭的制备及其乙烷/乙烯分离性能
刘汝帅, 唐帆, 史晓东, 郝广平, 陆安慧
, doi: 10.1016/S1872-5805(24)60859-0
摘要(170) HTML(53) PDF(20)
摘要:
乙烷(C2H6)与乙烯(C2H4)的高效分离对于制备聚合物级C2H4至关重要,需要开发选择性高和稳定性好的C2H6/C2H4吸附剂。本文以酚醛树脂为前驱体,FeCl3为铁源,通过在室温下聚合及800 ºC下炭化的方法制备了高石墨化度多孔炭(GC-800),并利用VASP计算证实了石墨化的多孔炭表面与C2H6分子间的结合能更高。石墨化度的增加可以有效提高多孔炭对C2H6的吸附能力,但高温下Fe的催化石墨化过程会破坏多孔炭的微孔结构,从而降低C2H6/C2H4的分离能力。通过调控炭化温度,实现了对多孔炭的石墨化度与孔隙结构的协同优化。拉曼光谱和XPS的数据分析表明,GC-800具有高的石墨化度,且sp2 C的含量高达73%。低温N2物理吸附技术测算出GC-800的比表面积高达574 m2·g−1。在298 K和1 bar的条件下GC-800对C2H6的平衡吸附容量为2.16 mmol·g−1,C2H6/C2H4(1∶1和1∶9,v/v)IAST选择性分别达到2.4和3.8,显著高于大多数报道的高性能C2H6选择性吸附剂。动态穿透实验表明GC-800可以从C2H6和C2H4混合物中一步获得高纯度的C2H4。动态循环测试证实了GC-800具有良好的循环稳定性,含湿条件下GC-800仍然能高效分离C2H6/C2H4 乙烷(C2H6)与乙烯(C2H4)的高效分离对于制备聚合物级C2H4至关重要,需要开发选择性高和稳定性好的C2H6/C2H4吸附剂。本文以酚醛树脂为前驱体,FeCl3为铁源,通过在室温下聚合及800 ºC下炭化的方法制备了高石墨化度多孔炭(GC-800),并利用VASP计算证实了石墨化的多孔炭表面与C2H6分子间的结合能更高。石墨化度的增加可以有效提高多孔炭对C2H6的吸附能力,但高温下Fe的催化石墨化过程会破坏多孔炭的微孔结构,从而降低C2H6/C2H4的分离能力。通过调控炭化温度,实现了对多孔炭的石墨化度与孔隙结构的协同优化。拉曼光谱和XPS的数据分析表明,GC-800具有高的石墨化度,且sp2 C的含量高达73%。低温N2物理吸附技术测算出GC-800的比表面积高达574 m2·g−1。在298 K和1 bar的条件下GC-800对C2H6的平衡吸附容量为2.16 mmol·g−1,C2H6/C2H4(1∶1和1∶9,v/v)IAST选择性分别达到2.4和3.8,显著高于大多数报道的高性能C2H6选择性吸附剂。动态穿透实验表明GC-800可以从C2H6和C2H4混合物中一步获得高纯度的C2H4。动态循环测试证实了GC-800具有良好的循环稳定性,含湿条件下GC-800仍然能高效分离C2H6/C2H4
Semi-quantitative analysis on the structural evolution of mesophase pitch-based carbon foams by Raman and FTIR spectroscopy
LIU Yue, CHANG Sheng-kai, SU Zhan-peng, HUANG Zu-jian, QIN Ji, YANG Jian-xiao
, doi: 10.1016/S1872-5805(24)60867-X
摘要(64) HTML(23) PDF(3)
摘要:
In this work, graphitized carbon foams (GFm) were prepared using mesophase pitch (MP) as a raw material through the foaming (450 °C), pre-oxidation (320 °C), carbonization (1000 °C), and graphitization (2800 °C) processes. Further, the differences in structure and properties of GFm prepared from different MP precursors which were pretreated by ball milling or liquid phase extraction were investigated and compared, and semi-quantitative calculations were conducted on the Raman and FTIR spectra of samples at each preparation stage. Semi-quantitative spectroscopic analysis provided the detailed information on the structure and chemical composition evolutions of MP and its derived GFm. Combined with microscopic observation for confirmation, the evolution mechanism from precursors to GFm during the preparation process was systematically analyzed. The results showed that ball milling could concentrate the mass distribution of aromatics in pitch, which contributed to uniform foaming, obtaining GFm with uniform pore distribution, and fine comprehensive properties. Liquid phase extraction helped to remove light components while retaining large aromatics to form carbonaceous planes with the largest average size during post-treatments, obtaining GFm with the highest graphitization degree and the fewest open holes, thus presenting the best compression resistance (2.47 MPa), the highest thermal conductivity (64.47 W/(m·K)) and the lowest electrical resistance (13.02 μΩ·m). The characterization strategy by combining semi-quantitative spectroscopic analysis with microscopic observation proposed in this work could provide the receivable theory of knowledge for controlling the preparation of MP-derived GFm. In this work, graphitized carbon foams (GFm) were prepared using mesophase pitch (MP) as a raw material through the foaming (450 °C), pre-oxidation (320 °C), carbonization (1000 °C), and graphitization (2800 °C) processes. Further, the differences in structure and properties of GFm prepared from different MP precursors which were pretreated by ball milling or liquid phase extraction were investigated and compared, and semi-quantitative calculations were conducted on the Raman and FTIR spectra of samples at each preparation stage. Semi-quantitative spectroscopic analysis provided the detailed information on the structure and chemical composition evolutions of MP and its derived GFm. Combined with microscopic observation for confirmation, the evolution mechanism from precursors to GFm during the preparation process was systematically analyzed. The results showed that ball milling could concentrate the mass distribution of aromatics in pitch, which contributed to uniform foaming, obtaining GFm with uniform pore distribution, and fine comprehensive properties. Liquid phase extraction helped to remove light components while retaining large aromatics to form carbonaceous planes with the largest average size during post-treatments, obtaining GFm with the highest graphitization degree and the fewest open holes, thus presenting the best compression resistance (2.47 MPa), the highest thermal conductivity (64.47 W/(m·K)) and the lowest electrical resistance (13.02 μΩ·m). The characterization strategy by combining semi-quantitative spectroscopic analysis with microscopic observation proposed in this work could provide the receivable theory of knowledge for controlling the preparation of MP-derived GFm.
Simple synthesis of pitch-derived carbon anode for high-performance potassium-ion batteries
JIANG Ming-chi, SUN Ning, YU Jia-xu, WANG Ti-zheng, Razium Ali Somoro, JIA Meng-qiu, XU Bin
, doi: 10.1016/S1872-5805(24)60868-1
摘要(67) HTML(29) PDF(3)
摘要:
Potassium-ion batteries (PIBs) hold promise for large-scale energy storage, necessitating the development of high-performance anode materials. Carbon with the advantage of structural versatility, is recognized as the most promising anode materials for commercialization. However, the relationship between carbon anode structure and their electrochemical performance remains unclear. Herein, a series of pitch-based soft carbon materials with different structures are fabricated by adjusting the carbonization temperatures at the range of 600–1400 °C, and their electrochemical K-storage performance has been systematically investigated. Among all, MTP700, with a relatively high disordered degree and larger interlayer spacing, exhibits a high reversible capacity of 329.4 mAh g−1 with a high initial coulombic efficiency of 72.81% and a maintained high capacity of 144.2 mAh g−1 at the current rate of 5 C. The study investigated the variation of carbon configurations and K-storage performances in relation to carbonization temperature, elucidating the correlation between the microcrystal size and the low-potential plateau region capacity as well as the structural disordered degree with the sloping region capacity. These findings can enrich the fundamental understanding of the K-storage process in carbon anodes, and thus facilitate the advancement of PIBs. Potassium-ion batteries (PIBs) hold promise for large-scale energy storage, necessitating the development of high-performance anode materials. Carbon with the advantage of structural versatility, is recognized as the most promising anode materials for commercialization. However, the relationship between carbon anode structure and their electrochemical performance remains unclear. Herein, a series of pitch-based soft carbon materials with different structures are fabricated by adjusting the carbonization temperatures at the range of 600–1400 °C, and their electrochemical K-storage performance has been systematically investigated. Among all, MTP700, with a relatively high disordered degree and larger interlayer spacing, exhibits a high reversible capacity of 329.4 mAh g−1 with a high initial coulombic efficiency of 72.81% and a maintained high capacity of 144.2 mAh g−1 at the current rate of 5 C. The study investigated the variation of carbon configurations and K-storage performances in relation to carbonization temperature, elucidating the correlation between the microcrystal size and the low-potential plateau region capacity as well as the structural disordered degree with the sloping region capacity. These findings can enrich the fundamental understanding of the K-storage process in carbon anodes, and thus facilitate the advancement of PIBs.
Ablation behaviour and mechanical performance of ZrB2-ZrC-SiC modified carbon/carbon composites prepared by vacuum filtration combined with reactive melt infiltration
ZHANG Jia-ping, SU Xiao-xuan, LI Xin-gang, WANG Run-ning, FU Qian-gang
, doi: 10.1016/S1872-5805(24)60841-3
摘要(231) HTML(135) PDF(54)
摘要:
The development of advanced aircrafts relies on high performance thermal-structural materials and composites of carbon/carbon (C/C) with ultrahigh-temperature ceramics are ideal candidates. However, traditional routes of compositing are either inefficient and expensive or lead to non-uniform distribution of ceramics in the matrix. Here, vacuum filtration of ZrB2 was successfully applied to introduce ZrB2-ZrC-SiC into C/C as a supplement for reactive melt infiltration ZrSi2, which contributed to the content increase and uniform distribution of the introduced ceramic phases. The mass and linear ablation rates of the composites were reduced by 68.9% and 29.7%, respectively, compared to those of C/C-ZrC-SiC composites prepared through reactive melt infiltration. The ablation performance was improved because of the volatilization of B2O3, taking a part of the heat away, and more uniformly distributed ZrO2 that could promote the formation of ZrO2-SiO2 continuous protective layer. This efficiently resisted the mechanical denudation and hindered the oxygen infiltration. The development of advanced aircrafts relies on high performance thermal-structural materials and composites of carbon/carbon (C/C) with ultrahigh-temperature ceramics are ideal candidates. However, traditional routes of compositing are either inefficient and expensive or lead to non-uniform distribution of ceramics in the matrix. Here, vacuum filtration of ZrB2 was successfully applied to introduce ZrB2-ZrC-SiC into C/C as a supplement for reactive melt infiltration ZrSi2, which contributed to the content increase and uniform distribution of the introduced ceramic phases. The mass and linear ablation rates of the composites were reduced by 68.9% and 29.7%, respectively, compared to those of C/C-ZrC-SiC composites prepared through reactive melt infiltration. The ablation performance was improved because of the volatilization of B2O3, taking a part of the heat away, and more uniformly distributed ZrO2 that could promote the formation of ZrO2-SiO2 continuous protective layer. This efficiently resisted the mechanical denudation and hindered the oxygen infiltration.
RGO@SiC porous films based multilayer electromagnetic shields
LI Jing, Qi Yi-quan, ZHAO Shi-xiang, QIU Han-xun, YANG Jun-he, YANG Guang-zhi
, doi: 10.1016/S1872-5805(24)60855-3
摘要(48) HTML(27) PDF(9)
摘要:
Development of lightweight and flexible thin films for electromagnetic interference (EMI) shielding is of great significance. In this paper, RGO@SiC porous thin films were prepared for EMI shielding. The porous structure was easily obtained by 3 s of solid phase microwave irradiation, which resulted in an efficient reduction of GO and a significant increase of the film thickness from around 20 to 200 μm. The SET of the RGO@SiC porous thin film reached 35.6 dB, while the SER was only 2.8 dB. The addition of SiC whiskers was critical for the multi-reflection, interfacial polarization and dielectric attenuation of EM waves. Further, the multilayer composites with a gradient change from transmission to reflection were constructed by stacking the RGO@SiC porous films and using multi-walled carbon nanotubes buckypaper as the reflection layer. The highest SET reached 75.1 dB with a SER value of 2.7 dB and a thickness of about 1.5 mm. We believe the porous RGO@SiC thin films were promising for designing multilayer or sandwich structure as EMI absorption packaging or lining materials. Development of lightweight and flexible thin films for electromagnetic interference (EMI) shielding is of great significance. In this paper, RGO@SiC porous thin films were prepared for EMI shielding. The porous structure was easily obtained by 3 s of solid phase microwave irradiation, which resulted in an efficient reduction of GO and a significant increase of the film thickness from around 20 to 200 μm. The SET of the RGO@SiC porous thin film reached 35.6 dB, while the SER was only 2.8 dB. The addition of SiC whiskers was critical for the multi-reflection, interfacial polarization and dielectric attenuation of EM waves. Further, the multilayer composites with a gradient change from transmission to reflection were constructed by stacking the RGO@SiC porous films and using multi-walled carbon nanotubes buckypaper as the reflection layer. The highest SET reached 75.1 dB with a SER value of 2.7 dB and a thickness of about 1.5 mm. We believe the porous RGO@SiC thin films were promising for designing multilayer or sandwich structure as EMI absorption packaging or lining materials.
Revealing the correlation of high-frequency performance of supercapacitors with doped nitrogen species
FAN Ya-feng, YI Zong-lin, ZHOU Yi, XIE Li-jing, SUN Guo-hua, WANG Zhen-bing, Huang Xian-hong, SU Fang-yuan, CHEN Cheng-meng
, doi: 10.1016/S1872-5805(24)60849-8
摘要(66) HTML(28) PDF(7)
摘要:
Nitrogen doping strategy has been widely used to enhance the performance of carbon electrodes in supercapacitors, particularly in terms of high-frequency response. However, the charge storage and ion response mechanisms of different nitrogen dopants at high frequencies are still unclear. In this study, we employ carbonized melamine foam with an open surface structure as a simplified model electrode material, enabling a comprehensive analysis of their impact on the ionic response behavior of high-frequency supercapacitors. Through a combination of experiments and first-principles calculations, we uncover that pyrrolic nitrogen, characterized by a higher adsorption energy, enhances the charge storage capacity of the electrode at high frequencies. On the other hand, graphitic nitrogen, with a lower adsorption energy, promotes rapid ion response. Furthermore, we propose the use of adsorption energy as a practical descriptor for electrode/electrolyte design in high-frequency applications, offering a more universal approach for optimizing the performance of N-doped carbon materials. This research contributes to the advancement of high-frequency supercapacitor technology and provides guidance for the development of improved N-doped carbon materials. Nitrogen doping strategy has been widely used to enhance the performance of carbon electrodes in supercapacitors, particularly in terms of high-frequency response. However, the charge storage and ion response mechanisms of different nitrogen dopants at high frequencies are still unclear. In this study, we employ carbonized melamine foam with an open surface structure as a simplified model electrode material, enabling a comprehensive analysis of their impact on the ionic response behavior of high-frequency supercapacitors. Through a combination of experiments and first-principles calculations, we uncover that pyrrolic nitrogen, characterized by a higher adsorption energy, enhances the charge storage capacity of the electrode at high frequencies. On the other hand, graphitic nitrogen, with a lower adsorption energy, promotes rapid ion response. Furthermore, we propose the use of adsorption energy as a practical descriptor for electrode/electrolyte design in high-frequency applications, offering a more universal approach for optimizing the performance of N-doped carbon materials. This research contributes to the advancement of high-frequency supercapacitor technology and provides guidance for the development of improved N-doped carbon materials.
Porous silicon/carbon composite for high-performance lithium-ion batteries
TIAN Zhen-yu, WANG Ya-fei, QIN Xin, Shaislamov Ulugbek, Hojamberdiev Mirabbos, ZHENG Tong-hui, DONG Shuo, ZHANG Xing-hao, KONG De-bin, ZHI Lin-jie
, doi: 10.1016/S1872-5805(24)60850-4
摘要(126) HTML(114) PDF(36)
摘要:
Silicon anodes are promising candidates for lithium-ion batteries. However, their practical application is severely limited due to their significant volume expansion leading to irreversible material fracture and electrical disconnection. This study proposes a new top-down strategy for preparing microsized porous silicon and introducing polyacrylonitrile (PAN) as nitrogen-doped carbon coating, which is designed to maintain the internal space and alleviate the outward expansion of the silicon anode during the lithiation and delithiation process. Subsequently, we explored the effect of temperature on the thermal transition behavior of PAN and the electrochemical behavior of the composite electrode. After the treatment at 400 °C, the PAN coating retained a high nitrogen doping content of 11.35%, which explicitly confirmed the existence of C―N and C―O bonds that improved the ionic-electronic transport properties. This treatment not only retained a more intact carbon layer structure, but also introduced carbon defects, exhibiting remarkably stable cycling even at high rates. When cycled at 4 A g−1, the optimized anode exhibited a specific capacity of 857.6 mAh g−1 even after 200 cycles, demonstrating great potential for high-capacity energy storage applications. Silicon anodes are promising candidates for lithium-ion batteries. However, their practical application is severely limited due to their significant volume expansion leading to irreversible material fracture and electrical disconnection. This study proposes a new top-down strategy for preparing microsized porous silicon and introducing polyacrylonitrile (PAN) as nitrogen-doped carbon coating, which is designed to maintain the internal space and alleviate the outward expansion of the silicon anode during the lithiation and delithiation process. Subsequently, we explored the effect of temperature on the thermal transition behavior of PAN and the electrochemical behavior of the composite electrode. After the treatment at 400 °C, the PAN coating retained a high nitrogen doping content of 11.35%, which explicitly confirmed the existence of C―N and C―O bonds that improved the ionic-electronic transport properties. This treatment not only retained a more intact carbon layer structure, but also introduced carbon defects, exhibiting remarkably stable cycling even at high rates. When cycled at 4 A g−1, the optimized anode exhibited a specific capacity of 857.6 mAh g−1 even after 200 cycles, demonstrating great potential for high-capacity energy storage applications.
Wet-composition-induced amorphous adhesion toward a high interfacial shear strength between carbon fiber and polyetherketoneketone
ZHANG Feng, LI Bo-lan, JIAO Meng-xiao, LI Yan-bo, WANG Xin, YANG Yu, YANG Yu-qiu, ZHANG Xiao-hua
, doi: 10.1016/S1872-5805(22)60646-2
摘要(473) HTML(299) PDF(56)
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.
Cardo poly (ether sulfone) toughened E51/DETDA epoxy resin and its carbon fiber composites
WU Rong-peng, ZHANG Xing-hua, WEI Xing-hai, JING De-qi, SU Wei-guo, ZHANG Shou-chun
, doi: 10.1016/S1872-5805(23)60741-3
摘要(245) HTML(147) PDF(54)
摘要:
A toughener that can effectively improve the interlaminar toughness in carbon fiber composites is crucial for various applications. In this paper, the toughening effects of phenolphthalein-based cardo poly (ether sulfone) (PES-C) on E51/ DETDA epoxy and its carbon fiber composites (CFCs) were investigated. The SEM results showed that PES-C/epoxy blends formed a sea-island phase and bicontinuous phase structure, which was associated with reaction-induced phase separation. After adding 15 g m−2 PES-C, the glass transition temperature (Tg) of the 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% compared to that of the control laminate. The increase in GIIC could be attributed to the cohesive failure and plastic deformation in the interleaving region. A toughener that can effectively improve the interlaminar toughness in carbon fiber composites is crucial for various applications. In this paper, the toughening effects of phenolphthalein-based cardo poly (ether sulfone) (PES-C) on E51/ DETDA epoxy and its carbon fiber composites (CFCs) were investigated. The SEM results showed that PES-C/epoxy blends formed a sea-island phase and bicontinuous phase structure, which was associated with reaction-induced phase separation. After adding 15 g m−2 PES-C, the glass transition temperature (Tg) of the 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% compared to that of the control laminate. The increase in GIIC could be attributed to the cohesive failure and plastic deformation in the interleaving region.
Fluorescence color tuning of dual-emission biomass carbon quantum dots and their application in Fe3+ and Cu2+ detection
Xue Jia-jia, GAN Mei-heng, LU Yong-gen, WU Qi-lin
, doi: 10.1016/S1872-5805(24)60869-3
摘要(38) HTML(25) PDF(3)
摘要:
Using simple and eco-friendly solvothermal treatment, dual-emission biomass carbon quantum dots (D-BCQDs) were successfully synthesized from biomass Viburnum awabuki leaves. The resultant dual emission peaks appeared at 490 and 675 nm under a single 413 nm excitation wavelength. Only by changing the reaction temperature (140–240 °C), multicolor D-BCQDs could emit crimson, red, purplish red, purple, and blue-gray fluorescence, respectively. XPS and FTIR characterization indicated that the tunable fluorescence color mechanism was mainly attributed to surface oxidation defects, nitrogen elemental content, and sp2-C/sp3-C hybridized structural domains. D-BCQDs can not only respectively detect Fe3+ and Cu2+, but also quantify the ratio of Fe3+ and Cu2+ in mixed solutions, demonstrating their potential application in the simultaneous detection of multiple ions. Using simple and eco-friendly solvothermal treatment, dual-emission biomass carbon quantum dots (D-BCQDs) were successfully synthesized from biomass Viburnum awabuki leaves. The resultant dual emission peaks appeared at 490 and 675 nm under a single 413 nm excitation wavelength. Only by changing the reaction temperature (140–240 °C), multicolor D-BCQDs could emit crimson, red, purplish red, purple, and blue-gray fluorescence, respectively. XPS and FTIR characterization indicated that the tunable fluorescence color mechanism was mainly attributed to surface oxidation defects, nitrogen elemental content, and sp2-C/sp3-C hybridized structural domains. D-BCQDs can not only respectively detect Fe3+ and Cu2+, but also quantify the ratio of Fe3+ and Cu2+ in mixed solutions, demonstrating their potential application in the simultaneous detection of multiple ions.
Synergistic enhancement of toughness and viscosity of carbon nanotubes/polyether imide/polyether ether ketone nanocomposites
SONG Jiu-peng, ZHAO Yan, LI Xue-kuan, XIONG Shu, LI Shuang, WANG Kai
, doi: 10.1016/S1872-5805(22)60643-7
摘要(543) HTML(278) PDF(38)
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.