MXene的制备及其复合材料在能源光催化领域的应用进展

MXene作为一种拥有层状结构的二维材料,具有良好的吸附催化性能、较宽的光吸收范围、高导热性、高硬度、高熔点、高导电性以及大比表面积等物理和化学特性,在储能、催化、润滑、抗菌、电磁屏蔽等领域有着较高应用价值。本文着重介绍了由前驱体MAX相获得MXene的制备方法,综述了MXene复合材料在光催化固氮、析氢、CO₂还原等能源光催化领域的应用进展。     

多孔碳材料的制备

多孔碳材料不仅具有碳材料化学稳定高、导电性好等优点,由于多孔结构的引入,还具有比表面积高、孔道结构丰富、孔径可调等特点,在催化、吸附和电化学储能等方面都得到了广泛的应用。本文综述了微孔、介孔、大孔及多级孔碳等多孔碳材料的最新研究进展,重点介绍了多孔碳孔道结构的调控,并对多孔碳材料的应用进行了展望。     

氢氧化钾活化制备超级电容器多孔碳电极材料

具有高比表面积、良好导电性的多孔碳材料在超级电容器中有着广泛的应用前景. 大量的研究工作致力于通过物理或者化学手段合成并调控多孔材料的微观结构. 在众多多孔碳材料的制备方式中,氢氧化钾作为一种高效的活化剂,常用于制备具有良好孔径分布和高比表面积多孔碳电极材料. 本文主要结合作者课题组的研究工作,着重概述利用氢氧化钾活化sp²碳纳米材料制备多孔碳材料的机理过程、结构形貌的转变以及所得材料的电化学性能,希望对发展新型的高性能基多孔碳材料的超级电容器电极材料有所帮助.     

大片单层低缺陷MXene的制备及其膜材料的电磁屏蔽性能

采用原位生成氢氟酸法刻蚀Ti₃AlC₂制备了单片层二维过渡金属碳化物(MXene), 用扫描电子显微镜(SEM)、 透射电子显微镜(TEM)及原子力显微镜(AFM)等表征了MXene的微观形貌. 结果表明, 所制备的MXene材料具有大片、 单层及低缺陷等特点. 通过抽滤MXene分散液制备的MXene膜材料具有导电性高(3280 S/cm)及韧性优异等特点. MXene膜的屏蔽性能测试结果表明, 8 μm厚的MXene膜屏蔽效能为60.6 dB, SSE/t值则高达19531.1 dB·cm ²·g ^-1. 推测MXene膜的屏蔽机理是一种以吸收为主的电磁干扰屏蔽机制.     

二维MXene材料的制备与电化学储能应用

将MAX相陶瓷通过液相刻蚀等方法移除A原子层可得到与石墨烯（Graphene）类似二维结构的过渡金属碳或氮化物（MXene）,是近年来二维材料领域出现的新成员。独特的二维结构与丰富可调的组分使得MXene具有优异的导电与机械性能、高亲水表面与离子传输性能,受到越来越广泛的关注。目前已成功制备出的MXene材料有20余种,研究发现MXene应用于锂离子、非锂离子（如Na⁺、K⁺、Mg²⁺、Ca²⁺和Al³⁺）二次电池和电化学超级电容器均表现出优异的性能,是一种很有潜力的电极材料。本文总结对比了MXene材料制备方法,简要概述了MXene材料的电子、电磁与机械性能,重点介绍了MXene在电化学电池与超级电容器储能方面的应用,最后对MXene材料目前存在的主要问题及未来研究与应用前景进行了展望。     

二维材料V2C MXene的制备与应用

MXenes是二维过渡金属碳化物、氮化物和碳氮化物的总称,因其独特的物理和化学性质被广泛应用于储能、催化、电磁等领域。作为MXenes中重要的一员,V₂C MXene具有高导电性和低离子传输势垒的特性,并且多氧化态的钒元素使其也具有赝电容特性。因此,V₂C MXene在许多方面尤其是电化学储能上表现出优异的性能,但是V₂C MXene较高的形成能所导致的制备难度大和结构的不稳定性制约了其发展。本文综述了V₂C MXene在制备、结构、性能和应用方面的研究进展,重点关注制备方法和在电化学储能以及电催化析氢上的应用。同时对V₂C MXene存在的主要问题、未来的研究方向和应用前景进行了展望。     

SiO2阶层多孔结构搭建及块体材料制备机理

借助溶胶-凝胶结合相分离和模板法进行了阶层多孔结构的搭建及二氧化硅多孔块体材料的制备,表征了阶层多孔块体的显微结构及孔结构特性,分析了阶层多孔结构的搭建机理。研究结果表明,三嵌段共聚物聚环氧乙烷-聚环氧丙烷-聚环氧乙烷（P123）的加入不仅诱导共混体系发生相分离,调控大孔结构的形成,同时形成球形胶束并作为模板剂进入骨架,而1,3,5-三甲基苯（TMB）的加入使P123形成的胶束膨胀且更加稳定,在骨架上成功引入了球形介孔,骨架中凝胶粒子相互聚集形成微孔,从而搭建贯通大孔-球形介孔-微孔同时分布的阶层多孔结构,并获得相应的多孔块体材料;当正硅酸甲酯（TMOS）：P123：TMB摩尔比为1：0.015：0.353时,多孔块体材料的阶层多孔结构最优,大孔孔径为0.5-1.5 μm,介孔孔径为3-4 nm,显气孔率66.1%,比表面积为616 m²·g^-1。     

新型多孔氮化硼材料

多孔氮化硼材料是一种新型多孔非氧化物材料,具有高比表面积、可调孔径、良好的化学惰性和热稳定性等特点,在催化、储氢、气体吸附和分离等领域具有巨大的应用潜力,是材料领域研究热点之一。依孔径的不同,多孔氮化硼材料被分为微孔氮化硼、介孔氮化硼、大孔氮化硼和多级孔氮化硼。本文综述了微孔、介孔、大孔及多级孔等类型氮化硼材料的研究进展。重点介绍了不同类型氮化硼材料的制备和性能,并分析了各种制备方法的优缺点,最后探讨了多孔氮化硼材料的发展前景。     

电磁屏蔽材料的研究进展

介绍了电磁屏蔽材料在军用和民用领域的重要性;简要阐述了电磁屏蔽的机理;综述了4种不同电磁屏蔽材料的优缺点以及研究现状,分别为金属型、表面导电型、填充复合型和本征型导电聚合物电磁屏蔽材料;分析并提出了3种提高电磁屏蔽效能的方式,分别为多孔结构设计、多层结构设计、复合填料优化。     

微生物发酵诱导多孔材料: 制备方法和应用

微生物发酵作为一种新的制备多孔材料的方式, 将微生物发酵工程与发泡工程有机结合起来, 克服了传统制备方法需要特殊设备、 操作复杂、 后处理繁琐、 化学药品污染和成本昂贵等缺点, 受到了广泛关注.本文基于微生物发酵多孔材料的研究, 围绕多孔材料的定义和多孔水凝胶的分类及制备方式进行总结.针对微生物发酵诱导制备多孔材料的制备方法, 综合评述了该方法在染料吸附、 海水蒸发脱盐、 电磁屏蔽以及制备新型功能性生物材料等方面的应用.最后, 对微生物诱导制备多孔材料的未来发展进行了展望.     

Recent advance in electromagnetic shielding of MXenes

As a new type of two-dimensional material,MXene's unique layered structure,outstanding electrical conductivity,low density,tunable surface chemistry,and solution processability make it receive extensive attention in various fields,especially for the lightweight shielding mate rials since the report on electromagnetic interference(EMI) shielding of 2D Ti_3 C_2 T_x in 2016.In this review,the progress on the MXe nes material including their synthetic strategies,prope rties and EMI application is highlighted.First,the recent advance on the different synthesis methods and properties of MXene is summarized.According to their intrinsic characteristics,the application of MXene in EMI fields is then discussed.Finally,the challenges and perspective on the future development of MXene in low-cost preparation and practical application are proposed.     

Recent progress in MXene and graphene based nanocomposites for microwave absorption and electromagnetic interference shielding

There is widespread use of telecommunication and microwave technology in modern society, and raised the electromagnetic interference (EMI) issue to alarming situation due to apprehensive demand and growth of 5G technology undesirably disturbing the human health. The two dimensional (2D) materials including graphene and MXenes are already been used for variety of electronic devices due to their exceptional electrical, mechanical, optical, chemical, and thermal properties. MXene is composed of metal carbides, in which mainly metals are the building blocks for dielectrics, semiconductors, or semimetals. However, the strong interfaces with electromagnetic waves (EM) are variable from terahertz (THz) to gigahertz (GHz) frequency levels and are widely used in EMI and Microwave absorption (MA) for mobile networks and communication technologies. The use of different organic materials with metal, organic, inorganic fillers, polymers nanocomposite and MXene as a novel material has been studied to address the recent advancement and challenges in the microwave absorption mechanism of 2D materials and their nanocomposites. In this concern, various techniques and materials has been reported for the improvement of shielding effectiveness (SE), and theoretical aspects of EMI shielding performance, as well stability of 2D materials particularly MXene, graphene and its nanocomposites. Consequently, various materials including polymers, conducting polymers, and metal–organic frameworks (MOF) have also been discussed by introducing various strategies for improved MA and control of EMI shieling. Here in this comprehensive review, we summarized the recent developments on material synthesis and fabrication of MXene based nanocomposites for EMI shielding and MA. This research work is a comprehensive review majorly focuses on the fundamentals of EMI/MA.  The recent developments and challenges of the MXene and graphene based various structures with different polymeric composites are described in a broader perspective.     

Tough and Conductive Nacre-inspired MXene/Epoxy Layered Bulk Nanocomposites

A long-standing quest in materials science has been the development of tough epoxy resin nanocomposites for use in numerous applications. Inspired by nacre, here we report tough and conductive MXene/epoxy layered bulk nanocomposites. The orientation of MXene lamellar scaffolds is enhanced by annealing treatment. The improved interfacial interactions between MXene lamellar scaffold and epoxy through surface chemical modification resulted in a synergistic effect. Tailoring the interlayer spacing of MXene nanosheets to a critical distance resulted in a fracture toughness about eight times higher than that of pure epoxy, surpassing other epoxy nanocomposites. Our nacre-inspired MXene/epoxy layered bulk nanocomposites also show high electrical conductivity that provides self-monitoring capability for structural integrity and exhibits an excellent electromagnetic interference shielding efficiency. Our proposed strategy provides an avenue for fabricating high-performance epoxy nanocomposites.     

碳纳米管/聚合物复合材料

本文简要介绍了碳纳米管的纯化和表面改性方法，着重对碳纳米管/聚合物复合材料的制备方法、微观结构表征及其力学、电学、光学等性能的研究进行了综述；简述了此类复合材料在电学、电磁屏蔽材料及吸波隐身材料、纤维材料以及航天工业等领域的应用，探讨了该研究领域所面临的一些问题及今后的发展方向。     

2D MXenes as Perspective Immobilization Platforms for Design of Electrochemical Nanobiosensors

MXenes are a new group of 2D nanomaterials with fascinating properties including high electrical conductivity, hydrophilic nature, easily tunable structure and high surface area. This is why MXene modified interfaces are extremely promising for the preparation of sensitive electrochemical biosensors. While there are numerous reports on MXene‐based enzymatic biosensors for detection of a wide range of analytes, application of MXene for construction of affinity biosensors is in its infancy. The review article summarizes current state‐of the‐art in the field with a focus on MXene modifications needed for construction of robust and high performance MXene electrochemical biosensors.     

一维聚苯胺纳米材料的制备方法研究进展

一维聚苯胺纳米材料具有电导率高、环境稳定性好、分散性好、比表面积大、扩散路径短等独特性能以及易于大量生产和成本相对低廉等优点,在传感器与传动器、防腐涂料、电磁屏蔽等领域应用潜力大,成为目前研究最为广泛的导电聚合物纳米材料之一,其制备方法也日益成为研究的热点。综述了近年来一维聚苯胺纳米材料制备方法的最新研究进展,介绍了模板法、非模板法和电纺法等制备方法,并对各种不同制备方法的优缺点进行了比较分析。     

3D石墨烯基气凝胶的制备及在超级电容器中的应用

超级电容器作为一种新型的能源存储装置,由于其较高的功率密度、优良的充放电特性、超长的循环寿命,使其在移动电源,新能源汽车等众多领域具有非常广泛的应用前景。3D石墨烯基气凝胶具有多孔结构、大的比表面积、高的导电率、优异的机械性能和电子传输能力,它一直被认为是超级电容器的理想电极材料。本文综述了3D石墨烯基气凝胶的制备方法及其在超级电容器中的应用现状,并展望了其在超级电容器中的应用前景。