金属纳米团簇的合成及其光致发光性质的调控

金属纳米团簇是一种既具有出色光物理性质,又具有良好生物相容性的零维材料.利用配体对团簇的热力学稳定产物的选择性和还原剂动力学调控可以合成出结构多样的金属纳米团簇,在光学材料、生物医学和催化材料等领域展示出颇具潜力的应用前景.但金属纳米团簇的稳定性差、发光弱等缺点限制了其实际应用,因此通过聚集诱导发光效应和超分子自组装协同调控金属纳米团簇的稳定性及光学性质,可以构筑出结构与发光可控的金属纳米团簇组装体,有效促进金属纳米团簇的实际可用性.本文简要介绍了不同配体保护的金属纳米团簇的合成,阐述了金属纳米团簇的光致发光性质,总结了聚集诱导发光效应对团簇超分子组装体光致发光性质的影响规律,并分析提出了当前研究仍存在的问题及对未来探究的展望.     

纳米碳分子——合成化学的魅力

碳材料的发展极大地推动了人类科技的进步。碳材料通过碳原子之间不同的键合方式、结构和排列，使其具有丰富的性质，并且更多新型碳材料还不断地被发现或合成出来。作为新型碳材料的纳米碳分子由于其本身所拥有的潜在优良性质，在有机电子学、材料科学如生物材料等领域具有广阔的应用前景，因此被誉为是未来最有开发前景的材料。在过去的四十年里，新型纳米碳分子的发现和创造已彻底改变了碳材料的格局，打开了一扇通往全新科学领域的大门。本文重点介绍了近年来具有新颖拓扑结构的纳米碳分子的结构特征以及如何通过有机合成的手段对其进行精准构筑。     

表面限域效应下的区域选择性脱氢环化合成纳米石墨烯分子

<正>纳米石墨烯作为一类重要的有机半导体材料在分子电子学、自旋电子学和光电子学中有着广泛的应用前景~(1–3)。化学家利用设计的分子前驱体在溶液中自下而上地合成了众多具有不同尺寸和边界结构的纳米石墨烯分子~4,为精细调控纳米石墨烯的电学性质提供了途径。但是溶液法合成过     

Cu2O/Ag纳米复合物的表面增强拉曼光谱

用一种简单的化学还原方法制备了银纳米粒子包覆的氧化亚铜（Cu2O）纳米复合物。扫描电子显微镜显示Cu2O 为八面体型的纳米粒子,表面光滑,结构对称。包覆的Ag部分占据Cu2O粒子表面。通过比较Ag/Cu2O纳米复合物、Ag溶胶及Cu纳米粒子表面吸附的4-巯基吡啶（4-Mpy）分子表面增强拉曼光谱（SERS）发现,利用此方法得到了Cu2O粒子表面吸附分子的拉曼光谱。银纳米粒子所产生的电磁场增强又增强了吸附在Cu2O上的4-Mpy拉曼信号。这种方法为初步研究Cu2O表面吸附分子性质提供了依据,扩宽了SERS的使用范围,使SERS应用在纳米半导体材料上成为可能。     

高分子量聚二茂铁衍生物的性质与应用

综述了近年来高分子量聚二茂铁衍生物性能及应用研究的进展。聚二茂铁衍生物均聚物和嵌段共聚物表现出独特的电、光、磁和氧化不原性质，在材料科学、超分子科学和纳米结构材料方面的应用前景良好。     

纳米晶体材料研究进展

综述了目前纳米晶体材料合成、结构、性质和应用的研究和发展现状。通过惰性气体凝结、机械合金、等离子体技术和其他许多方法可以制得纳米晶体材料。尽管早期的研究者认为纳米晶体材料的晶粒边界结构不同于常规材料, 但目前有关纳米晶体材料结构的研究表明其具有与常规晶体材料相同的晶粒边界结构。纳米晶体材料所具有的诸如扩散和烧结、力学、陶瓷和金属间化合物的延展性、电学、热膨胀、光学、磁学、催化和腐蚀行为等性质优于常规多晶材料, 这些性质具有巨大的潜在应用价值。     

级次纳米结构材料及其液相合成

级次纳米结构材料因其新颖的结构,独特的化学、物理性质,以及形貌和尺寸对这些性质极大地影响,使得它在光、电、磁等方面的性质更加丰富, 为实现由下到上构建纳米器件提供了坚实的基础。由此级次纳米结构材料引起化学家和材料学家的极大兴趣, 成为纳米材料化学领域中引人注目的研究方向之一。本文综述了近年来国内外级次纳米结构材料的最新研究进展,重点介绍了介孔材料、具有级次结构的空心球、气凝胶和其他典型的级次纳米结构,归纳了级次纳米结构制备中的各种液相合成方法及其特点,讨论了级次纳米结构的合成机制及各种影响因素,并在此基础上对级次纳米结构材料在一些领域的应用前景进行了展望。     

聚合物纳米杂化材料的控制合成、自组装及功能化

聚合物纳米杂化材料的制备及功能化是当前国际前沿研究课题之一.特殊结构的聚合物可以通过分子间特殊相互作用,在纳米尺度上自发地组装成具有特殊结构和形态的集合体,这类材料在新材料、电子以及生物医学等领域具有广泛的应用前景.本文介绍国内外,特别是厦门大学在双亲性分子及嵌段共聚物的模板自组装、基于POSS单体纳米构筑单元以及POSS嵌段聚合物自组装的有机/无机纳米杂化材料、模板控制导电高分子材料纳米形态构筑等领域材料的可控合成和组装,与此同时对相关材料的性能及功能化应用进行了简要的讨论.     

手性金团簇的制备、性质及应用

手性作为生命体固有的自然属性广泛存在于从微观到宏观的自然界中,其现象包括具有高度手性偏好的生物小分子(如L-氨基酸和D-糖),具有不对称空间构象的生物大分子(如DNA双螺旋链),以及其他所有由手性分子或手性结构参与的生理和生化过程。研究者们成功地把分子手性引入到金团簇的表面诞生了一种新的材料——手性金团簇,这种新型纳米级的手性材料实现了手性信号从分子尺度到纳米尺度的跨越。作为一类集表面手性、特殊光学活性和金团簇独特性质于一体的新型纳米材料,手性金团簇在手性催化、手性识别、分子检测等领域具有广泛的应用前景。本文主要综述了手性金团簇的制备、表征、性质及应用,并对其发展前景及面临的挑战进行了总结与展望。     

封面图形简介

封面上的图形为一种具有功能组装特性的Ｃ60 衍生物分子的三维结构模型。通过分子设计 ,依靠自组装技术制备Ｃ60 衍生物分子薄膜结构 ,是北京大学纳米科技中心纳米化学研究室刘忠范教授研究组与北京大学稀土材料与化学国家重点实验室甘良兵教授研究组联合进行的一项研究工作。　　Ｃ60 分子的特殊结构以及由此所产生的一系列独特的物理化学性能 ,使其成为纳米科技领域极重要的功能材料。很自然的 ,如何能够把Ｃ60 分子固定在固体基片上形成二维薄膜成为一个焦点和热点问题。因为这是研究Ｃ60分 子各种性质并争取付诸于实际的必要环节。ＳＴ…     

Recent Progresses in the Investigation of Rare-earth Boron Inverse Sandwich Clusters

While rare-earth borides represent a class of important materials in modern industries, there are few fundamental researches on their electronic structures and physicochemical properties. Recently, we have performed combined experimental and theoretical studies on rare-earth boron clusters and their cluster-assembled complexes, revealing a series of rare-earth inverse sandwich clusters with fascinating electronic structures and chemical bonding patterns. In this overview article, we summarize recent progresses in this area and provide a perspective view on the future development of rare-earth boride clusters. Understanding the electronic structures of these clusters helps to design materials of f-element(lanthanide and actinide) borides with critical physiochemical properties.     

Dependence of the Properties of 2D Nanocomposites Generated by Covalent Crosslinking of Nanosheets on the Interlayer Separation: A Combined Experimental and Theoretical Study

Covalently cross-linked heterostructures of 2D materials are a new class of materials which possess electrochemical and photochemical hydrogen evolution properties. It was of considerable interest to investigate the role of interlayer spacing in the nanocomposites involving MoS₂ and graphene sheets and its control over electronic structures and catalytic properties. We have investigated this problem with emphasis on the hydrogen evolution properties of these structures by a combined experimental and theoretical study. We have linked MoS₂ based nanocomposites with other 2D materials with varying interlayer spacing by changing the linker and studied their hydrogen evolution properties. The hydrogen evolution activity for these composites decreases with increasing linker length, which we can link to a decrease in magnitude of charge transfer across the layers with increasing interlayer spacing. Factors such as the nature of the sheets, interlayer distance as well as the nature of the linker provide pathways to tune the properties of covalently cross-linked 2D material rendering this new class of materials highly interesting.     

选择性催化混合单体制备多组分聚酯的研究进展

以聚乳酸和聚碳酸酯等为代表的生物可降解高分子材料已被应用于包装材料和生物医用等领域.然而受链段结构的影响,这类均聚物材料在实际应用中受到了一定限制.将不同性质聚合物链段通过共价键连接形成的嵌段共聚物具有组分均匀、性能可控等优点,是优化材料性能的一种方法.本文概述了环酯、环氧化物和CO2(或环状酸酐)的多元共聚反应合成嵌...     

Energetic materials based on poly furazan and furoxan structures

Furazan and furoxan represent fascinating explosophoric units with intriguing structures and unique properties. Compared with other nitrogen-rich heterocycles, most poly furazan and furoxan-based heterocycles demonstrate superior energetic performances due to the higher enthalpy of formation and density levels. A large variety of advanced energetic materials have been achieved based on the combination of furazan and furoxan moieties with different kinds of linkers and this review provides an overview of the development of energetic poly furazan and furoxan structures during the past decades, with their physical properties and detonation characteristics summarized and compared with traditional energetic materials. Various synthetic strategies towards these compact energetic structures are highlighted by covering the most important cyclization methods for construction of the hetercyclic scaffolds and the following modifications such as nitrations and oxidations. Given the synthetic availabilities and outstanding properties, energetic materials based on poly furazan and furoxan structures are undoubtedly listed as a promising candidate for the development of new-generation explosives, propellants and pyrotechnics.     

Needs and trends in rational synthesis of zeolitic materials

Zeolites are an important class of materials which are widely used in industry as catalysts, adsorbents and ion-exchangers. Their superior properties are closely related to their unique porous framework structure, as well as composition and morphology. The ever-growing needs for zeolitic materials in applications inspire us to think of the rational synthesis of zeolites with desired structures and properties. However, rationalization of zeolitic materials remains one of the most challenging issues in the zeolite research field due to their unclear formation mechanism. Despite this, many efforts have been devoted to synthesize zeolites in a more rational way. In this tutorial review, first, we demonstrate how the geometrical characteristics of zeolite frameworks affect the catalytic performances of the resulting materials; then, we present recent advances in synthetic innovations to target materials, and we further highlight the developments in computer simulations toward ab initio design and synthesis; finally, the future perspective on the rational synthesis of zeolitic materials with desired functions and structures will be described.     

Design of organophosphorus materials for organic electronics and bio-applications

π-Extended molecules are key components for the development of materials science. In fact, polyaromatic structures are fundamental for the scientific and technological progress of fields such as organic electronics and bio-applications. Beneficial properties of π-extended structures are absorption in the visible region, often luminescence, high electron mobilities and stability. Common approaches to adjust the properties of polyaromatic structures to functional setups involve changes in shape and size at the molecular level. Recently, incorporating hetero-elements emerged as successful approach. In this regard, organophosphorus conjugated molecules are new materials holding great promise for potential applications. In this review, we comprehensively discuss the design/development of polyaromatic phosphorus materials and their applicability. We establish structure/property/applicability relationships to provide key guidelines for the engineering of newer, future applications. This article thus provides a source of information for the further development of this rapidly evolving field of research.     

A nonlinear uniaxial stress-strain constitutive model for viscoelastic membrane materials

Membrane materials with the excellent thermal, optical, electrical and chemical properties have attracted significant attention in numerous research fields recently. However, while being used to construct the membrane structures, the mechanical behaviors of membrane materials are more foundational than the other properties in evaluating the structure safety. This paper thus proposes a nonlinear stress-strain constitutive model for revealing the viscoelastic behaviors of membrane materials under uniaxial tensile loading. To this end, the constitutive equations for expressing the uniaxial tensile stress-strain relationships of viscoelastic materials are established gradually from the kinematic equations of the generalized Maxwell model that includes several basic Maxwell models and one basic spring element. Meanwhile, the uniaxial tensile tests of two typical viscoelastic membrane materials were carried out in order to examine the proposed constitutive model. The constitutive model parameters of the stress-strain properties of both membrane materials are accurately identified using the least square method. By comparing the true stress-strain curves between experimental results and constitutive models, good agreements with the maximum differences of 4.67% and 3.41% are acquired for the two employed viscoelastic membrane materials, respectively. These observations are able to validate the accuracy and efficiency of this proposed constitutive model in predicting the uniaxial stress-strain behaviors of viscoelastic membrane materials, which are significant in the nonlinear structural analysis of membrane structures.     

Non‐Brownian Particle‐Based Materials with Microscale and Nanoscale Hierarchy

Colloidal crystals are interesting materials owing to their customizable photonic properties, high surface area, and analogy to chemical structures. The flexibility of these materials has been greatly enhanced through mixing particles with varying sizes, compositions, and surface charges. In this way, distinctive patterns or analogies to chemical stoichiometries are produced; however, to date, this body of research is limited to particles with nanoscale dimensions. A simple method is now presented for bottom‐up assembly of non‐Brownian particle mixtures to create a new class of hierarchically‐ordered materials that mimic those found in nature (both in pore distribution as well as stoichiometry). Additionally, these crystals serve as a template to create particle‐based inverted crystalline structures with customizable properties.     

含Silole共轭聚合物的光电性能

Silole是一类含硅杂环戊二烯,近年来,由于其独特的结构特性、分子的可设计性及多样性,在光电领域得到越来越多研究者们的关注。某些silole小分子在有机发光二极管中用作发光层和电子传输层有出色的表现,但近来对含silole聚合物的研究也颇受重视,在聚集态诱导发光、化学传感器、聚合物发光二极管、聚合物太阳能电池、场效应晶体管中的应用相继有报道。因此silole是一类很有潜力的构筑光电功能材料的杂环化合物。本文根据其母体结构的不同对含silole的聚合物光电性能研究进展进行了综述。     

稀土硫化物的研究进展

稀土硫化物是一类结构复杂、性能丰富、应用广泛的功能材料,在无机颜料、热电材料、光学材料及磁性材料等领域有着独特的优势和广阔的应用前景,是近些年来国际上的研究热点之一.本文总结了稀土硫化物的制备方法及其应用研究进展,对稀土硫化物制备的一些常见方法进行了总结和评述,对稀土硫化物的应用研究进行了总结,重点介绍了γ-稀土倍半硫化物的结构、性能特点以及相应的应用,尤其是它在环保颜料、高温热电材料以及纳米材料等领域中应用;此外,本文对稀土硫化物研究中还存在的一些问题进行了评述,并对未来的相关研究进行了展望.