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In this introductory paper an attempt is made to give an overview of the area of nanostructured materials irrespective of the synthesis process. The various microstructural features such as clusters or isolated nanoparticles, agglomerated nanopowders, consolidated nanomaterials and nanocomposite materials as well as all materials classes are considered. As an important component of modern research on nanomaterials a section describes the various characterization tools available. Based on these remarks some properties of nanostructured materials will be summarized emphasizing the property–microstructure relationships. Finally, a brief outlook on applications and initial industrial use of nanomaterials is presented.  相似文献   

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纳米磁性材料及其应用   总被引:17,自引:0,他引:17  
纳米磁性材料是纳米材料中最早进入工业化生产,应用十分广泛的一类功能材料,纳米磁性材料的特性不同于常规的磁性材料,其原因在于与磁性相关联的特征物理长庆恰好处于纳米量级,例如,磁单畴尺寸,超顺磁性临界尺寸,交换作用长度,以主电子平均自由路磁程自由路程等大致处于1-100nm量级,当磁性体的尺寸与这些特征物理长度相当时,就会呈现反常的磁学与电学性质,利用这些新特性,已涌现出一系列新材料与众多应用。  相似文献   

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Hydrogen has emerged as an environmentally attractive fuel and a promising energy carrier for future applications to meet the ever-increasing energy challenges. The safe and efficient storage and release of hydrogen remain a bottleneck for realizing the upcoming hydrogen economy. Hydrogen storage based on liquid-phase chemical hydrogen storage materials is one of the most promising hydrogen storage techniques, which offers considerable potential for large-scale practical applications for its excellent safety, great convenience, and high efficiency. Recently, nanopore-supported metal nanocatalysts have stood out remarkably in boosting the field of liquid-phase chemical hydrogen storage. Herein, the latest research progress in catalytic hydrogen production is summarized, from liquid-phase chemical hydrogen storage materials, such as formic acid, ammonia borane, hydrous hydrazine, and sodium borohydride, by using metal nanocatalysts confined within diverse nanoporous materials, such as metal–organic frameworks, porous carbons, zeolites, mesoporous silica, and porous organic polymers. The state-of-the-art synthetic strategies and advanced characterizations for these nanocatalysts, as well as their catalytic performances in hydrogen generation, are presented. The limitation of each hydrogen storage system and future challenges and opportunities on this subject are also discussed. References in related fields are provided, and more developments and applications to achieve hydrogen energy will be inspired.  相似文献   

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介绍了NSM的主要制作方法,包括气相凝固法、机械合金化法和喷雾转化法等。并概述了NSM在工业和尖端科学技术领域里的应用状况和前景。  相似文献   

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纳米材料的合成与制备   总被引:107,自引:5,他引:107  
本文综述了近年来在纳米材料合成与制备领域的一些最新研究进展,包括纳米粉体、块体及薄膜材料的物理与化学方法制备。  相似文献   

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Sensor technology has an important effect on many aspects in our society, and has gained much progress, propelled by the development of nanoscience and nanotechnology. Current research efforts are directed toward developing high‐performance gas sensors with low operating temperature at low fabrication costs. A gas sensor working at room temperature is very appealing as it provides very low power consumption and does not require a heater for high‐temperature operation, and hence simplifies the fabrication of sensor devices and reduces the operating cost. Nanostructured materials are at the core of the development of any room‐temperature sensing platform. The most important advances with regard to fundamental research, sensing mechanisms, and application of nanostructured materials for room‐temperature conductometric sensor devices are reviewed here. Particular emphasis is given to the relation between the nanostructure and sensor properties in an attempt to address structure–property correlations. Finally, some future research perspectives and new challenges that the field of room‐temperature sensors will have to address are also discussed.  相似文献   

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制备块体纳米/超细晶材料的大塑性变形技术   总被引:11,自引:3,他引:11  
综述了采用SPD技术制备块体超细晶(UFG)和纳米晶(NC)材料的几种新方法,如等通道角挤压、高压扭转、多向锻造、多向压缩、板条马氏体冷轧法、累积轧焊法、冷拔、反复弯曲平直法等,分析了采用这些工艺制备的块体纳米材料所共有的微观组织特点。着重阐述了SPD技术的研究进展。  相似文献   

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From a materials science point of view, graphene is essentially a polymer having a giant, two‐dimensional molecular configuration. In this Progress Report, solvated graphene and its derivatives are illustrated from the perspective of soft matter. Firstly, the key appealing features of graphene as a molecular building block for assembling bulk soft materials are highlighed. It is then demonstrated how the intersheet interactions in solution are correlated with the molecular structure of graphene, and how a combination of the unique molecular structure and colloidal interactions can lead to simple, solution‐phase approaches for assembling graphenes into a variety of macroscopic nanoarchitectures. A number of new exciting functions and applications are also highlighted, which are enabled by the solvation effect and in particular, it is discussed why and how solvated graphenes can offer exciting functions that are unattainable with the dried, hard counterpart. The discussion is concluded with some personal perspectives on the future directions in which this emerging class of functional soft materials could be pursued.  相似文献   

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Atomic layer deposition (ALD) is a thin film technology that in the past two decades rapidly developed from a niche technology to an established method. It proved to be a key technology for the surface modification and the fabrication of complex nanostructured materials. In this Progress Report, after a short introduction to ALD and its chemistry, the versatility of the technique for the fabrication of novel functional materials will be discussed. Selected examples, focused on its use for the engineering of nanostructures targeting applications in energy conversion and storage, and on environmental issues, will be discussed. Finally, the challenges that ALD is now facing in terms of materials fabrication and processing will be also tackled.  相似文献   

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形态可控的碳纳米材料由于独特的结构和性能而受到研究者的普遍关注,常见的制备方法有化学气相沉积法(CVD)、乳液法和水热碳化法等。水热碳化法是一种重要的碳纳米材料制备方法,具有成本低、反应条件温和、产物粒径均匀且形态可控等特点。综述了近年来以糖类及淀粉等有机物为原料,采用水热碳化法制备各种形态可控碳纳米材料的研究现状,重点介绍了水热碳化工艺条件对合成碳微球、空心碳微球、核壳结构碳复合材料显微形貌的影响,并提出了水热碳化法制备碳纳米材料研究中存在的问题和今后可能的发展方向。  相似文献   

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The term “engineered zeolitic materials” refers to a class of materials with a rationally designed pore system and active‐sites distribution. They are primarily made of crystalline microporous zeolites as the main building blocks, which can be accompanied by other secondary components to form composite materials. These materials are of potential importance in many industrial fields like catalysis or selective adsorption. Herein, critical aspects related to the synthesis and modification of such materials are discussed. The first section provides a short introduction on classical zeolite structures and properties, and their conventional synthesis methods. Then, the motivating rationale behind the growing demand for structural alteration of these zeolitic materials is discussed, with an emphasis on the ongoing struggles regarding mass‐transfer issues. The state‐of‐the‐art techniques that are currently available for overcoming these hurdles are reviewed. Following this, the focus is set on core–shell composites as one of the promising pathways toward the creation of a new generation of highly versatile and efficient engineered zeolitic substances. The synthesis approaches developed thus far to make zeolitic core–shell materials and their analogues, yolk–shell, and hollow materials, are also examined and summarized. Finally, the last section concisely reviews the performance of novel core–shell, yolk–shell, and hollow zeolitic materials for some important industrial applications.  相似文献   

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实验研究表明,纳米材料的晶粒生长速率远低于传统晶粒长大理论所预测的生长速率,为解释这一异常的晶粒生长行为,研究者提出了各种理论模型。综述了纳米晶粒生长理论模型的研究现状:第一类为动力学模型,通过钉轧晶界实现延缓晶粒的生长,起钉轧晶界作用的有溶质原子、三叉晶界和第二相等;第二类是热力学模型,通过降低晶界能来降低晶粒生长的驱动力,从而实现延缓晶粒的生长,如溶质原子偏析晶界和空位注入模型等。对各种理论模型进行了描述和分析,并展望了其发展方向。  相似文献   

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Sodium–ion batteries (NIBs), due to the advantages of low cost and relatively high safety, have attracted widespread attention all over the world, making them a promising candidate for large‐scale energy storage systems. However, the inherent lower energy density to lithium–ion batteries is the issue that should be further investigated and optimized. Toward the grid‐level energy storage applications, designing and discovering appropriate anode materials for NIBs are of great concern. Although many efforts on the improvements and innovations are achieved, several challenges still limit the current requirements of the large‐scale application, including low energy/power densities, moderate cycle performance, and the low initial Coulombic efficiency. Advanced nanostructured strategies for anode materials can significantly improve ion or electron transport kinetic performance enhancing the electrochemical properties of battery systems. Herein, this Review intends to provide a comprehensive summary on the progress of nanostructured anode materials for NIBs, where representative examples and corresponding storage mechanisms are discussed. Meanwhile, the potential directions to obtain high‐performance anode materials of NIBs are also proposed, which provide references for the further development of advanced anode materials for NIBs.  相似文献   

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Biological nanoparticles found in living systems possess distinct molecular architectures and diverse functions. Glycogen is a unique biological polysaccharide nanoparticle fabricated by nature through a bottom-up approach. The biocatalytic synthesis of glycogen has evolved over time to form a nanometer-sized dendrimer-like structure (20–150 nm) with a highly branched surface and a dense core. This makes glycogen markedly different from other natural linear or branched polysaccharides and particularly attractive as a platform for biomedical applications. Glycogen is inherently biodegradable, nontoxic, and can be functionalized with diverse surface and internal motifs for enhanced biofunctional properties. Recently, there has been growing interest in glycogen as a natural alternative to synthetic polymers and nanoparticles in a range of applications. Herein, the recent literature on glycogen in the material-based sciences, including its use as a constituent in biodegradable hydrogels and fibers, drug delivery vectors, tumor targeting and penetrating nanoparticles, immunomodulators, vaccine adjuvants, and contrast agents, is reviewed. The various methods of chemical functionalization and physical assembly of glycogen nanoparticles into multicomponent nanodevices, which advance glycogen toward a functional therapeutic nanoparticle from nature and back again, are discussed in detail.  相似文献   

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Tubular and fibrous nanostructures of titanates have recently been synthesized and characterized. Three general approaches (template assisted, anodic oxidation, and alkaline hydrothermal) for the preparation of nanostructured titanate and TiO2 are reviewed. The crystal structures, morphologies, and mechanism of formation of nanostructured titanates produced by the alkaline hydrothermal method are critically discussed. The physicochemical properties of nanostructured titanates are highlighted and the links between properties and applications are emphasized. Examples of early applications of nanostructured titanates in catalysis, photocatalysis, electrocatalysis, lithium batteries, hydrogen storage, and solar‐cell technologies are reviewed. The stability of titanate nanotubes at elevated temperatures and in acid media is considered.  相似文献   

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