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Ni2P纳米材料特殊的结构使其在催化领域显示出优异的活性和稳定性。作为催化材料,Ni2P的催化性能主要依赖于其结构、形貌及尺寸大小,实现Ni2P纳米材料的可控合成将是催化材料领域研究的热点。综述了Ni2P纳米材料的控制合成方法、合成机理及其在催化性能方面的研究进展,讨论了Ni2P纳米材料的应用前景,并从电子结构层次对Ni2P催化性能做了定性解释。Ni2P结构中由于P原子的掺入使得"d空穴"增多,费米能级附近的态密度增加,表现出类贵金属的特性,具有很好的催化性能。Ni2P纳米材料的催化脱氢性能将是继加氢性能之后又一个崭新的应用领域。 相似文献
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目前无机纳米材料的研究主要集中于低维无机纳米材料的制备,如纳米颗粒、纳米纤维等,其制备方法已相当成熟,而对高维特殊形貌无机纳米材料的研究相对较少。近年来,具有特殊形貌的高维无机纳米材料因独特的结构和表面性质在催化、太阳能电池、传感器、微波吸收、医学等领域展现出优于低维纳米材料的性能,但制备出的材料种类少,形貌不均一,可控性较差。因此,研究者们致力于特殊形貌无机纳米材料生长机理的研究,为材料制备提供有效的理论依据。制备无机纳米材料的方法有微乳液法、溶胶-凝胶法、电化学法、水/溶剂热法等。其中水/溶剂热法制备的无机纳米材料具有晶粒发育完整、粒度分布均匀、颗粒之间少团聚、原料价格较便宜的优点,因此被广泛应用于特殊形貌无机纳米材料的制备。自组装技术作为超分子领域的新概念,在制备特殊形貌的材料中发挥着重要作用,其主要作用是将低维的纳米结构单元通过氢键、范德华力、静电力等非共价键作用力进行连接而组装成各种复杂的层级结构。现已通过自组装技术合成了片状、棒状、花状、海绵状、树枝状等特殊形貌无机纳米材料。其中片状材料的生长过程如下:第一步是纳米颗粒的奥斯特瓦尔德熟化过程,第二步是熟化的纳米颗粒定向附着自组装成片状材料。棒状材料的生长过程出现了两种情况,第一种与片状形成过程相同,第二种则是先形成片状,然后片状发生卷曲形成棒状材料,棒状材料再定向附着自组装成长径比不同的棒状材料。花状、海绵状、树枝状等复杂形貌的形成则是基于片状或棒状材料,通过氢键自组装而成。自组装过程会受到表面活性剂或模板剂、溶剂、沉淀剂、酸碱度等因素的影响。研究者们发现利用水热法制备纳米材料时,引入合适的表面活性剂或模板剂,能够促使低维纳米结构单元进行有序自组装而形成结晶度好、尺寸均匀的特殊形貌纳米材料。通过改变表面活性剂或模板剂、溶剂、沉淀剂的种类和剂量及酸碱度等因素,影响纳米颗粒的生长方向、生长速率及颗粒之间的作用力,进而控制产品的形貌和尺寸。本文对近年来国内外利用自组装技术制备特殊形貌无机纳米材料的研究成果进行了介绍,分析讨论了自组装过程的影响因素,并对自组装制备特殊形貌无机纳米材料的发展方向和应用前景进行了展望,以期为制备性能优越的特殊形貌纳米材料提供参考。 相似文献
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形貌及尺寸规整可控的纳米晶体的合成是目前十分引人注目的纳米材料研究领域,制备合成中的形貌调控及其功能化是这些纳米材料能够得到应用的关键问题。采用直接水相还原法在聚丙烯酸钠保护下制备了银树枝形纳米结构,并将这种银树枝纳米晶溶胶滴加在经过预处理的玻璃基底上,通过自组装制备了银纳米树枝结构阵列。通过扫描电镜(SEM)观察了这种样品的微观结构,并用透射率测试研究了其光学性能。 相似文献
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《中国材料进展》2016,(4)
由于纳米材料具有不同于宏观块材的特性,诸如量子尺寸效应、小尺寸效应等,越来越多的科学家致力于纳米材料的合成和介观特性的研究,推广其在现实生产生活中的应用。磁性纳米材料,如铁、钴、镍等,具有独特的磁学和催化等介观特性,近年来得到了广泛关注。发展高度可控且温和、简便的合成方法,构筑具有优异特性的新型纳米结构,实现对目标材料物理、化学性质的剪裁,已经发展成为无机纳米材料合成的重要发展方向。目前,磁性纳米材料的合成方法取得了广泛的研究,可以有效实现磁性纳米材料的可控合成及组装。通过对材料的微结构调控可以有效控制材料的尺寸、形貌、成分及表界面性质,从而实现对磁性纳米材料的磁学、催化等介观性质的优化。 相似文献
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Two‐Dimensional Nanomaterials for Biomedical Applications: Emerging Trends and Future Prospects
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David Chimene Daniel L. Alge Akhilesh K. Gaharwar 《Advanced materials (Deerfield Beach, Fla.)》2015,27(45):7261-7284
Two‐dimensional (2D) nanomaterials are ultrathin nanomaterials with a high degree of anisotropy and chemical functionality. Research on 2D nanomaterials is still in its infancy, with the majority of research focusing on elucidating unique material characteristics and few reports focusing on biomedical applications of 2D nanomaterials. Nevertheless, recent rapid advances in 2D nanomaterials have raised important and exciting questions about their interactions with biological moieties. 2D nanoparticles such as carbon‐based 2D materials, silicate clays, transition metal dichalcogenides (TMDs), and transition metal oxides (TMOs) provide enhanced physical, chemical, and biological functionality owing to their uniform shapes, high surface‐to‐volume ratios, and surface charge. Here, we focus on state‐of‐the‐art biomedical applications of 2D nanomaterials as well as recent developments that are shaping this emerging field. Specifically, we describe the unique characteristics that make 2D nanoparticles so valuable, as well as the biocompatibility framework that has been investigated so far. Finally, to both capture the growing trend of 2D nanomaterials for biomedical applications and to identify promising new research directions, we provide a critical evaluation of potential applications of recently developed 2D nanomaterials. 相似文献
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Amorphous/Crystalline Hetero‐Phase Pd Nanosheets: One‐Pot Synthesis and Highly Selective Hydrogenation Reaction
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Nailiang Yang Hongfei Cheng Xiaozhi Liu Qinbai Yun Ye Chen Bing Li Bo Chen Zhicheng Zhang Xiaoping Chen Qipeng Lu Jingtao Huang Ying Huang Yun Zong Yanhui Yang Lin Gu Hua Zhang 《Advanced materials (Deerfield Beach, Fla.)》2018,30(39)
Similar to heterostructures composed of different materials, possessing unique properties due to the synergistic effect between different components, the crystal‐phase heterostructures, one variety of hetero‐phase structures, composed of different crystal phases in monometallic nanomaterials are herein developed, in order to explore crystal‐phase‐based applications. As novel hetero‐phase structures, amorphous/crystalline heterostructures are highly desired, since they often exhibit unique properties, and hold promise in various applications, but these structures have rarely been studied in noble metals. Herein, via a one‐pot wet‐chemical method, a series of amorphous/crystalline hetero‐phase Pd nanosheets is synthesized with different crystallinities for the catalytic 4‐nitrostyrene hydrogenation. The chemoselectivity and activity can be fine‐tuned by controlling the crystallinity of the as‐synthesized Pd nanosheets. This work might pave the way to preparing various hetero‐phase nanostructures for promising applications. 相似文献
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Two-dimensional (2D) nanomaterials are an emerging class of biomaterials with remarkable potential for biomedical applications. The planar topography of these nanomaterials confers unique physical, chemical, electronic and optical properties, making them attractive candidates for therapeutic delivery, biosensing, bioimaging, regenerative medicine, and additive manufacturing strategies. The high surface-to-volume ratio of 2D nanomaterials promotes enhanced interactions with biomolecules and cells. A range of 2D nanomaterials, including transition metal dichalcogenides (TMDs), layered double hydroxides (LDHs), layered silicates (nanoclays), 2D metal carbides and nitrides (MXenes), metal–organic framework (MOFs), covalent organic frameworks (COFs) and polymer nanosheets have been investigated for their potential in biomedical applications. Here, we will critically evaluate recent advances of 2D nanomaterial strategies in biomedical engineering and discuss emerging approaches and current limitations associated with these nanomaterials. Due to their unique physical, chemical, and biological properties, this new class of nanomaterials has the potential to become a platform technology in regenerative medicine and other biomedical applications. 相似文献
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Rong‐Mei Kong Xiao‐Bing Zhang Zhuo Chen Weihong Tan 《Small (Weinheim an der Bergstrasse, Germany)》2011,7(17):2428-2436
Aptamers represent a class of single‐stranded DNA or RNA oligonucleotides that play important roles in biosensing and biomedical applications. However, aptamers can gain more flexibility as molecular recognition tools by taking advantage of the unique chemical and physical properties provided by nanomaterials. Such aptamer–nanomaterial conjugates are having an increasing impact in the fields of biosensing, bioimaging, and therapy. The recent advances and limitations of aptamer‐assembled nanomaterials in biosensing and biomedical applications are briefly introduced and discussed. 相似文献
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As nanotechnology rapidly advanced over the past decades, a variety of nanomaterials have been developed and studied. Among them, SiC nanomaterials have recently attracted increasing attention for their demonstrated unique chemical and physical properties as well as wide potential applications. This article provides a comprehensive review of the recent progress on the synthesis, novel properties, and applications of SiC nanomaterials. It begins with the introduction of various techniques used for the rational design and synthesis of SiC nanomaterials, with an emphasis on vapor-based and solution-based methods. Discussion is then made on the mechanical, luminescent, electrical, thermal, and wetting properties of SiC nanomaterials as well as the characterizations that reveal them. Thereafter, various intriguing applications particularly in composites, field emitters, field effect transistors, sensors, nanoelectromechanical devices, catalyst, supercapacitors, bioimaging probes and microwave absorbers are highlighted. Finally, this review is concluded with an outlook of future research on SiC nanomaterials, major challenges to be met and possible solutions. 相似文献
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In recent years, the unique properties of magnetic functional nanomaterials have received considerable attentions and show promising applications in separation, detection, diagnosis, catalysis, environment remediation and so on. Specifically, introducing magnetic nanomaterials (MNPs) into traditional sensing techniques greatly simplifies detection operation and improves sensing performances, which makes magnetic nanomaterial-based sensing techniques become a hot research topic. Compared with other sensing techniques such as chromatography, fluorescence, mass spectrum and electrochemistry, surface-enhanced Raman scattering (SERS) displays unique properties of high-sensitivity, fingerprint specificity and nondestructive detection. The introduction of MNPs in SERS has proven to be an efficient way to resolve several critical challenges in practical SERS analysis leading to highly efficient target separation and enrichment, high-sensitive detection and precise outcomes analysis. This makes the MNPs involved SERS analysis a powerful technique with very appealing and promising application in various branches of analytical science. In this review, we first briefly introduced the preparation, encapsulation and surface modification of magnetic nanoparticles, assembly of magnetic nanoparticle–plasmonic substrates and then discussed their applications in SERS analysis, including biomedical application, environmental analysis, food safety and chemical reaction monitoring. Finally, we presented some outlooks on further developments of magnetic nanoparticles in SERS applications. 相似文献
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《材料科学技术学报》2015,(6)
Boron nitride(BN) nanostructures with complementary functions to their carbon counterparts are one of the most intriguing nanomaterials.Here we devote a compact review on the syntheses of BN nanomaterials:typical zero-dimensional(OD) fullerenes and nanoparticles,one-dimensional(1D) nanotubes and nanoribbons,two-dimensional(2D) nanosheets as well as three-dimensional(3D) nanoporous BN.Combining low-dimensional quantum confinement and surface effects with unique physical and chemical properties of BN,e.g.excellent electric insulation,wide band gap,and high chemical and thermal stability,BN nanomaterials have drawn particular attention in a variety of potential applications,e.g.luminescence,functional composites,hydrogen accumulators,and advanced insulators,which are also reviewed. 相似文献
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Advancement of Ag–Graphene Based Nanocomposites: An Overview of Synthesis and Its Applications
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Graphene has been employed as an excellent support for metal nanomaterials because of its unique structural and physicochemical properties. Silver nanoparticles (AgNPs) with exceptional properties have received considerable attention in various fields; however, particle aggregation limits its application. Therefore, the combination of AgNPs and graphene based nanocomposites (Ag–graphene based nanocomposites) has been widely explored to improve their properties and applications. Excitingly, enhanced antimicrobial, catalytic, and surface enhanced Raman scattering properties are obtained after their combination. In order to have a comprehensive knowledge of these nanocomposites, this Review highlights the chemical and biological synthesis of Ag–graphene nanocomposites. In particular, their applications as antimicrobial agents, catalysts, and sensors in biomedicine, agricultural protection, and environmental remediation and detection are covered. Meanwhile, the factors that influence the synthesis and applications are also briefly discussed. Furthermore, several important issues on the challenges and new directions are also provided for further development of these nanocomposites. 相似文献
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Muhammad Iqbal Yusuf Valentino Kaneti Jeonghun Kim Brian Yuliarto Yong‐Mook Kang Yoshio Bando Yoshiyuki Sugahara Yusuke Yamauchi 《Small (Weinheim an der Bergstrasse, Germany)》2019,15(6)
Palladium (Pd) plays an important role in numerous catalytic reactions, such as methanol and ethanol oxidation, oxygen reduction, hydrogenation, coupling reactions, and carbon monoxide oxidation. Creating Pd‐based nanoarchitectures with increased active surface sites, higher density of low‐coordinated atoms, and maximized surface coverage for the reactants is important. To address the limitations of pure Pd, various Pd‐based nanoarchitectures, including alloys, intermetallics, and supported Pd nanomaterials, have been fabricated by combining Pd with other elements with similar or higher catalytic activity for many catalytic reactions. Herein, recent advances in the preparation of Pd‐based nanoarchitectures through solution‐phase chemical reduction and electrochemical deposition methods are summarized. Finally, the trend and future outlook in the development of Pd nanocatalysts toward practical catalytic applications are discussed. 相似文献
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Advances in science and nanotechnology have facilitated the development of new methods for the preparation of pure selenium as selenium nanomaterials. They offer remarkable potential for technological applications in the fields of medicine, diagnostics, therapeutics, toxicology, electronics, catalysis and so on. Moreover, selenium nanomaterials also find applications in photographic exposure metres, rectifiers, signal emitting devices and transmitting devices, because of their unique structural, optical and electronic properties. This study describes a detailed advanced report on the synthesis, assembly, characterization and various applications of selenium nanomaterials. In addition, relevant synthesis methods, properties, challenges and opportunities associated with selenium nanomaterials are also presented. 相似文献