金属有机骨架和共价有机骨架及其衍生物用于超级电容器电极材料的研究进展

金属有机骨架(MOFs)和共价有机骨架(COFs)是一系列结晶多孔材料.由于其高度有序的结构、高的表面积、可调的孔径和拓扑结构、富含氧化还原活性位点的连续骨架,MOFs和COFs及其衍生物在储能领域引起了广泛关注.为了制造高性能超级电容器电极,MOFs和COFs及其衍生物具有结构稳定性好、氧化还原活性位点丰富和电子导电...     

MOFs及其衍生材料在锂离子电池负极中的研究进展

金属有机框架(MOFs)具有较大的比表面积和可调节的孔径，其金属离子和有机配体都具有良好的携电荷能力，近年来作为锂离子电池负极材料受到广泛关注。本文介绍了目前常用的锂离子电池MOFs负极材料，归纳了MOFs材料在锂离子电池负极中的改性策略和合成方法，且系统分析了MOFs及其衍生材料的结构与形貌设计的主要原则，指出了其未来发展趋势及研究挑战。     

基于组分设计的MOFs衍生碳基吸波材料的研究进展

金属有机骨架(MOFs)具有孔隙率高、比表面积大等特点,其衍生物重量轻、带宽宽、损耗能力强,具有有序规整以及易设计性的组分结构而被广泛用于电磁波吸收研究。总结了单金属、双金属及金属氧化物MOFs碳基吸波材料作为微波吸收材料的性能、优势及其在电磁波吸收方面的应用等,分析了不同组分和组分设计对电磁波吸收性能的影响。尽管还面临许多的挑战,但MOFs衍生物作为电磁波吸收材料显示出广阔的发展潜力。     

基于金属有机框架材料构建多相催化剂的研究进展

利用多相催化剂高效催化化学反应在能源化工、环境保护和可持续发展等方面具有重要的意义。基于金属有机框架复合材料(metal-organic frameworks, MOFs)的大比表面积、分散的活性中心和极高的孔隙率且孔结构可调等独特的结构特点,MOFs及其衍生物已被广泛应用于多相催化领域。按照MOFs催化剂活性位点的来源不同,从以下几个方面综述了近年来MOFs在多相催化领域的研究进展：MOFs本身无催化作用,仅仅作为催化剂载体起到携带催化剂和阻止催化剂团聚的作用;在MOFs上修饰官能团后,得到的衍生材料具有催化作用;MOFs自身具有不饱和的活性金属节点,促进反应进行。最后,展望了MOFs在多相催化领域的发展方向和应用前景。希望本篇综述能够帮助研究者更进一步了解MOFs及其衍生材料在构建多相催化剂方面的研究进展,为推动MOFs材料在多相催化方面的应用提供有意义的参考资料。     

硅材料在锂离子电池中的应用研究进展

硅材料作为锂离子电池负极材料具有比容量大的优点,是高容量锂离子负极材料的研究热点之一.综述了近年来锂离子电池硅负极材料的研究进展.分别对硅及含硅材料作为锂离子电池负极材料的发展过程、充放电特性、储锂机理及影响其储锂的各因素进行了分析和总结,并对其存在的问题进行了分析.探讨了采用不同复合物、不同制备方法和合成硅化物等改性方法来提高其循环性能的可行性.指出纳米硅基复合物将是硅负极材料最有希望的发展方向.     

低成本二氧化硅源镁热还原制备锂离子电池多孔硅负极材料的研究进展

硅材料因其超高的理论比容量、较低的放电电压及锂离子扩散势垒,成为最有发展前景的高容量锂离子电池负极材料之一.然而,硅负极在充放电过程中会引起巨大的体积膨胀,严重影响其电化学性能.设计具有纳米尺寸和多孔结构的硅负极材料是实现高容量硅负极的有效途径.但目前大多数的制备方法通常工艺复杂、成本高、产率低,限制了其商业应用.因此...     

锂离子电池硅基负极材料研究进展

硅基负极材料具有比容量大的优点,是高容量锂离子电池理想的负极材料。然而硅基材料在循环过程中容量衰减快,影响了其实用性。从硅复合物粉末和硅薄膜两个重要研究方面对硅基负极材料进行了综述,指出在Si基复合负极材料的研究中,单一途径改性提升循环性能的幅度有限,很难达到实用化阶段。硅的纳米化、无定形化、合金化及复合化等方法的综合运用成为硅基材料研究的主导方向。     

锂离子电池中高容量硅铝/碳复合负极材料的制备与性能研究

锂离子电池用高容量负极材料普遍存在首次不可逆容量高、循环性能差等问题. 本文采用高温固相法制备了硅铝/碳锂离子电池负极材料, 制备出的复合负极材料的比容量远高于目前锂离子电池普遍使用的中间相碳微球, 循环寿命则优于同粒度的硅单体为活性中心的硅碳复合材料. Al引入Si/C复合材料中, 有效抑制了材料的首次嵌锂深度,且减缓了电压滞后现象. 制备的复合负极材料首次可逆容量达到600mAh/g, 首次充放电效率在85\%以上, 25次循环后容量仍保持90%以上.     

锂离子电池用三维网状水系黏结剂的研究进展

硅材料由于具有很高的理论比容量(4200 mAh·g-1)而成为下一代锂离子电池的关键负极材料之一,但是其在嵌/脱锂过程中会产生巨大的体积变化,使电极的循环性能变差.黏结剂作为电极的主要成分之一承担着连接电极组分、维持电极结构稳定的重要作用,使用合适的黏结剂对于改善硅基负极的循环稳定性至关重要.带有极性官能团的水系黏结剂由于可以有效改善硅基负极的电化学性能而成为现在的研究热点.本文综述硅基负极水系黏结剂的研究进展,首先对单一线性结构黏结剂的性质进行归纳总结.在此基础上,对具有三维网状结构的复合黏结剂的研究进展进行重点介绍,详细讨论不同类型三维网状黏结剂的结构和性能特点,以及应用于硅基负极时对电极性能的改善效果.最后,提出硅基负极水系黏结剂所应具备的特性,旨在为硅基负极水系黏结剂的开发和选择提供思路.     

锂离子电池硅基负极材料的研究进展

硅负极材料具有很高的理论比容量(4200mAh/g),但充放电过程中巨大的体积变化导致其循环性能很差,同时较低的电导率以及与常规电解液的不相容性等因素限制了硅作为负极材料在锂离子电池中的应用。因此,目前大部分研究人员都致力于解决其循环性能差的问题。综述了近年来改善硅基负极材料性能的最新进展,指出了硅基材料作为锂离子电池负极材料的研究前景。     

Metal organic framework (MOF) in aqueous energy devices

Aqueous energy devices are under the spotlight of current research due to their safety, low cost and ease of handling. Metal-organic frameworks (MOFs) and their derivatives have spurred extensive exploration as they provide a library of new electrode materials. The rich and structural flexibilities (such as metal nodes, ligands, pore structure) endow MOFs and MOFs-derivatives with vast opportunities for various energy devices. In this review, we discuss the correlation between MOF structural parameters and electrochemical performance for aqueous energy devices in the scope of zinc-based batteries (Zn-ion, Zn-alkaline and Zn-air batteries), potassium-ion batteries and supercapacitors. For each energy device, the effect of determinative factors and structural modulating strategies of MOFs and derivatives are highlighted. Finally, we summarize the challenges and provide our perspective about MOFs and derivatives for future aqueous energy devices.     

Road Map for In Situ Grown Binder-Free MOFs and Their Derivatives as Freestanding Electrodes for Supercapacitors

Among several electrocatalysts for energy storage purposes including supercapacitors, metal–organic frameworks (MOFs), and their derivatives have spurred wide spread interest owing to their structural merits, multifariousness with tailor-made functionalities and tunable pore sizes. The electrochemical performance of supercapacitors can be further enhanced using in situ grown MOFs and their derivatives, eliminating the role of insulating binders whose “dead mass” contribution hampers the device capability otherwise. The expulsion of binders not only ensures better adhesion of catalyst material with the current collector but also facilitates the transport of electron and electrolyte ions and remedy cycle performance deterioration with better chemical stability. This review systematically summarizes different kinds of metal–ligand combinations for in situ grown MOFs and derivatives, preparation techniques, modification strategies, properties, and charge transport mechanisms as freestanding electrode materials in determining the performance of supercapacitors. In the end, the review also highlights potential promises, challenges, and state-of-the-art advancement in the rational design of electrodes to overcome the bottlenecks and to improve the capability of MOFs in energy storage applications.     

Rare-Earth–Modified Metal–Organic Frameworks and Derivatives for Photo/Electrocatalysis

Metal–organic frameworks (MOFs) and their derivatives have attracted much attention in the field of photo/electrocatalysis owing to their ultrahigh porosity, tunable properties, and superior coordination ability. Regulating the valence electronic structure and coordination environment of MOFs is an effective way to enhance their intrinsic catalytic performance. Rare earth (RE) elements with 4f orbital occupancy provide an opportunity to evoke electron rearrangement, accelerate charged carrier transport, and synergize the surface adsorption of catalysts. Therefore, the integration of RE with MOFs makes it possible to optimize their electronic structure and coordination environment, resulting in enhanced catalytic performance. In this review, progress in current research on the use of RE-modified MOFs and their derivatives for photo/electrocatalysis is summarized and discussed. First, the theoretical advantages of RE in MOF modification are introduced, with a focus on the roles of 4f orbital occupancy and RE ion organic coordination ligands. Then, the application of RE-modified MOFs and their derivatives in photo/electrocatalysis is systematically discussed. Finally, research challenges, future opportunities, and prospects for RE-MOFs are also discussed.     

金属有机框架材料载体系统在食品抗菌包装中的应用

目的 综述金属有机框架材料(Metal-organic frameworks,MOFs)作为载体系统在食品抗菌包装领域的研究现状和应用进展,以期为MOFs类抗菌包装材料的研发和应用提供参考。方法 介绍MOFs的基本概念及分类,概述MOFs的制备方法(加热法、机械法和电化学法等),总结归纳近年来MOFs作为载体系统在无机抗菌剂、有机抗菌剂和天然抗菌剂领域的应用,并讨论MOFs作为载体系统的机遇和挑战。结论 MOFs作为一种有机与无机相结合的多孔性复合材料,不仅可有效封装抗菌剂,实现缓释和控释,且将MOFs复合材料作为高分子填料可提高其抗菌性能、力学性能和抗紫外线性能等,因此在制备高效、安全的食品抗菌包装方面具有巨大潜力。     

Benchmarking the Effect of Particle Size on Silicon Anode Materials for Lithium-Ion Batteries (Small 42/2023)

High-capacity silicon has been regarded as one of the most promising anodes for high-energy lithium-ion batteries. However, it suffers from severe volume expansion, particle pulverization, and repeated solid electrolyte interphase (SEI) growth, which leads to rapid electrochemical failure, while the particle size also plays key role here and its effects remain elusive. In this paper, through multiple-physical, chemical, and synchrotron-based characterizations, the evolutions of the composition, structure, morphology, and surface chemistry of silicon anodes with the particle size ranging from 50 to 5 µm upon cycling are benchmarked, which greatly link to their electrochemical failure discrepancies. It is found that the nano- and micro-silicon anodes undergo similar crystal to amorphous phase transition, but quite different composition transition upon de-/lithiation; at the same time, the nano- and 1 µm-silicon samples present obviously different mechanochemical behaviors from the 5 µm-silicon sample, such as electrode crack, particle pulverization/crack as well as volume expansion; in addition, the micro-silicon samples possess much thinner SEI layer than the nano-silicon samples upon cycling, and also differences in SEI compositions. It is hoped this comprehensive study and understanding should offer critical insights into the exclusive and customized modification strategies to diverse silicon anodes ranging from nano to microscale.     

Exploring Critical Factors Affecting Strain Distribution in 1D Silicon‐Based Nanostructures for Lithium‐Ion Battery Anodes

Despite the advantage of high capacity, the practical use of the silicon anode is still hindered by large volume expansion during the severe pulverization lithiation process, which results in electrical contact loss and rapid capacity fading. Here, a combined electrochemical and computational study on the factor for accommodating volume expansion of silicon‐based anodes is shown. 1D silicon‐based nanostructures with different internal spaces to explore the effect of spatial ratio of voids and their distribution degree inside the fibers on structural stability are designed. Notably, lotus‐root‐type silicon nanowires with locally distributed void spaces can improve capacity retention and structural integrity with minimum silicon pulverization during lithium insertion and extraction. The findings of this study indicate that the distribution of buffer spaces, electrochemical surface area, as well as Li diffusion property significantly influence cycle performance and rate capability of the battery, which can be extended to other silicon‐based anodes to overcome large volume expansion.     

Semiconductor Metal–Organic Frameworks: Future Low‐Bandgap Materials

Metal–organic frameworks (MOFs) with low density, high porosity, and easy tunability of functionality and structural properties, represent potential candidates for use as semiconductor materials. The rapid development of the semiconductor industry and the continuous miniaturization of feature sizes of integrated circuits toward the nanometer (nm) scale require novel semiconductor materials instead of traditional materials like silicon, germanium, and gallium arsenide etc. MOFs with advantageous properties of both the inorganic and the organic components promise to serve as the next generation of semiconductor materials for the microelectronics industry with the potential to be extremely stable, cheap, and mechanically flexible. Here, a perspective of recent research is provided, regarding the semiconducting properties of MOFs, bandgap studies, and their potential in microelectronic devices.     

Metal–Organic Framework‐Derived Materials for Sodium Energy Storage

Recently, sodium‐ion batteries (SIBs) are extensively explored and are regarded as one of the most promising alternatives to lithium‐ion batteries for electrochemical energy conversion and storage, owing to the abundant raw material resources, low cost, and similar electrochemical behavior of elemental sodium compared to lithium. Metal–organic frameworks (MOFs) have attracted enormous attention due to their high surface areas, tunable structures, and diverse applications in drug delivery, gas storage, and catalysis. Recently, there has been an escalating interest in exploiting MOF‐derived materials as anodes for sodium energy storage due to their fast mass transport resulting from their highly porous structures and relatively simple preparation methods originating from in situ thermal treatment processes. In this Review, the recent progress of the sodium‐ion storage performances of MOF‐derived materials, including MOF‐derived porous carbons, metal oxides, metal oxide/carbon nanocomposites, and other materials (e.g., metal phosphides, metal sulfides, and metal selenides), as SIB anodes is systematically and completely presented and discussed. Moreover, the current challenges and perspectives of MOF‐derived materials in electrochemical energy storage are discussed.     

锂离子电池负极储锂材料的研究进展

储锂材料是影响锂离子电池性能的关键因素之一,已成为国际上锂离子电池材料研究领域的热点和重点。综述了锂离子电池负极储锂材料的研究进展,但非简单地重复负极储锂材料发展的全部研究。重点关注了三大类负极储锂材料的电化学特性、储锂机理和主要电化学改性途径,并指出了三类负极储锂材料存在的技术问题和今后的研究方向。