Oxidative Intercalation for Monometallic Ni2+‐Ni3+ Layered Double Hydroxide and Enhanced Capacitance in Exfoliated Nanosheets

Monometallic Ni²⁺‐Ni³⁺ layered double hydroxide (LDH) is prepared using a simple oxidative intercalation process and may be further exfoliated into positively charged Ni(OH)₂ unilamellar sheets. The superior capacitive behavior of the unilamellar sheets stranded in carbon nanotubes (CNTs) networks is achieved because of the complete interfacial charge storage arising from the confined Faradaic reactions at the interfacial region. 3D nanosheet/CNT composites are prepared using an in situ electrostatic assembly of positive charged sheets with CNTs bearing negative charges. The restacking of active nanosheets during electrochemical cycling is effectively prohibited. Consequently, the outstanding specific capacitance and remarkable rate capability of the nanosheet/CNT hybrid electrodes are demonstrated, making them promising candidates for high performance supercapacitors, combining high‐energy storage densities with high levels of power delivery.     

Beta‐Sheet‐Forming,Self‐Assembled Peptide Nanomaterials towards Optical,Energy, and Healthcare Applications

Peptide self‐assembly is an attractive route for the synthesis of intricate organic nanostructures that possess remarkable structural variety and biocompatibility. Recent studies on peptide‐based, self‐assembled materials have expanded beyond the construction of high‐order architectures; they are now reporting new functional materials that have application in the emerging fields such as artificial photosynthesis and rechargeable batteries. Nevertheless, there have been few reviews particularly concentrating on such versatile, emerging applications. Herein, recent advances in the synthesis of self‐assembled peptide nanomaterials (e.g., cross β‐sheet‐based amyloid nanostructures, peptide amphiphiles) are selectively reviewed and their new applications in diverse, interdisciplinary fields are described, ranging from optics and energy storage/conversion to healthcare. The applications of peptide‐based self‐assembled materials in unconventional fields are also highlighted, such as photoluminescent peptide nanostructures, artificial photosynthetic peptide nanomaterials, and lithium‐ion battery components. The relation of such functional materials to the rapidly progressing biomedical applications of peptide self‐assembly, which include biosensors/chips and regenerative medicine, are discussed. The combination of strategies shown in these applications would further promote the discovery of novel, functional, small materials.     

Transition metal/carbon nanoparticle composite catalysts as platinum substitutes for bioelectrochemical hydrogen production using microbial electrolysis cells

Various metal nanoparticle catalysts supported on Vulcan XC-72 and carbon-nanomaterial-based catalysts were fabricated and compared and assessed as substitutes of platinum in microbial electrolysis cells (MECs). The metal-nanoparticle-loaded cathodes exhibited relatively better hydrogen production and electrochemical properties than cathodes coated with carbon nanoparticles (CNPs) and carbon nanotubes (CNTs) did. Catalysts containing Pt (alone or mixed with other metals) most effectively produced hydrogen in terms of overall conversion efficiency, followed by Ni alone or combined with other metals in the order: Pt/C (80.6%) > PtNi/C (76.8%) > PtCu/C (72.6%) > Ni/C (73.0%) > Cu/C (65.8%) > CNPs (47.0%) > CNTs (38.9%) > plain carbon felt (38.7%). Further, in terms of long-term catalytic stability, Ni-based catalysts degraded to a lesser extent over time than did the Cu/C catalyst (which showed the maximum degradation). Overall, the hydrogen generation efficiency, catalyst stability, and current density of the Ni-based catalysts were almost comparable to those of Pt catalysts. Thus, Ni is an effective and inexpensive alternative to Pt catalysts for hydrogen production by MECs.     

功能纳米材料在石油开采中的应用进展

评述了功能性纳米材料在石油开采领域中的应用现状和进展;介绍了纳米材料的分类、制备方法、作用机理及现场应用效果等,并总结了功能性纳米材料在石油开采等应用过程中存在的问题。指出纳米材料具有明显有别于传统材料的特异物理化学性能,如高表面能、小尺寸、大比表面积、高晶界原子比率等。功能性纳米材料在石油开采等领域显示出广阔的应用前景。     

X射线Rietveld方法在纳米材料研究领域的应用

纳米材料由于独特的微结构和奇异性能成为当今世界范围内研究与开发的热点。鉴于Rietveld方法在常规固体材料方面广泛而成功的应用,将Rietveld方法引入到纳米研究领域具有重要的意义。简要介绍了Rietveld方法的基本原理及其在纳米材料的晶体结构精修、物相定量分析和微结构分析等方面的应用。     

碳纳米管构成的二维和三维碳纳米材料的研究进展

碳纳米管(CNTs)可以构成水平排列、垂直排列膜以及多种三维结构碳纳米材料.介绍了 CNTs构成的二维和三维碳纳米材料的分类,综述了其制备方法和应用的研究进展,探讨了该研究领域需要解决的问题以及今后可能的发展前景.     

乌克兰与白俄罗斯纳米金刚石的研究现状

简要地介绍了乌克兰和白俄罗斯纳米金刚石的研究现状。重点指出,静压合成的金刚石粉体在超硬材料研究所生产、研究与应用已有三十多年。乌克兰根据DSTU3992-95国家标准,将ASM5 0.1/0粒和ASM1 0.1/0两个等级作为纳米粉体来生产,其产量每月约100kg。白俄罗斯Sinta公司年产107克拉纳米金刚石,还可生产9个类型的纳米金刚石和含金刚石混合物制品。     

纳米材料在生物医学中的应用

本文介绍了纳米材料及其复合材料在生物医学领域各方面的应用     

Formation of Nanocrystalline Transition-Metal Ferrites inside a Silica Matrix

Nanocrystalline transition-metal ferrites were synthesized inside an amorphous silica matrix by the sol–gel method. The formation of spinel ferrites began above 400°C, giving fine particles of about 10 nm at 800°C. This is associated with a specific role of the silica matrix, which facilitates the diffusion of the reacting cations, enhancing the ferrite formation. Above 1000°C the MnFe₂O₄ and CuFe₂O₄ nanoparticles lost their fine nature. The dried gels and crystalline materials were characterized by X-ray diffraction, thermal, FTIR, and BET analyses as well as by high-resolution scanning transmission electron microscopy.     

Nanomaterial-based amplified transduction of biomolecular interactions

This article reviews progress in the development of nanomaterials for amplified biosensing and discusses different nanomaterial-based bioamplification strategies. Signal amplification has attracted considerable attention for ultrasensitive detection of disease markers and biothreat agents. The emergence of nanotechnology is opening new horizons for highly sensitive bioaffinity and biocatalytic assays and for novel biosensor protocols that employ electronic, optical, or microgravimetric signal transduction. Nucleic acids and antibodies functionalized with metal or semiconductor nanoparticles have been employed as amplifying tags for the detection of DNA and proteins. The coupling of different nanomaterial-based amplification platforms and amplification processes dramatically enhances the intensity of the analytical signal and leads to ultrasensitive bioassays. The successful realization of the new nanoparticle-based signal amplification strategies requires proper attention to nonspecific adsorption issues. The implications of such nanoscale materials on amplified biodetection protocols and on the development of modern biosensors are discussed.