2,089 publications from this institution
Nanowires constitute an important class of one-dimensional nanomaterials. Nanowires of a variety of materials have been synthesized and characterized in the last few years. Chemical routes as well as use of templates have dominated the strategies employed for the synthesis of nanowires. Many of the properties of inorganic nanowires are found to have potential technological applications. In this chapter, we present an overview of the synthesis, properties, and applications of nanowires of metals, metal oxides, chalcogenides, nitrides, and other inorganic nanowires.
Hydrogen generation by water splitting is clearly a predominant and essential strategy to tackle the problems related to renewable energy. In this context, the discovery of proper catalysts for electrochemical and photochemical water splitting assumes great importance. There is also a serious intent to eliminate platinum and other noble metal catalysts. To replace Pt by a non‐metallic catalyst with desirable characteristics is a challenge. Borocarbonitrides, (B x C y N z ) which constitutes a new class of 2D material, offer great promise as non‐metallic catalysts because of the easy tunability of bandgap, surface area, and other electronic properties with variation in composition. Recently, B x C y N z composites with excellent electrochemical and photochemical hydrogen generation activities have been found, especially noteworthy being the observation that B x C y N z with a carbon‐rich composition or its nanocomposites with MoS 2 come close to Pt in electrocatalytic properties, showing equally good photochemical activity.
A layered iron sulfate of the composition [H3N(CH2)2NH2(CH2)2NH2(CH2)2NH3][FeII3F6(SO4)2], possessing a distorted Kagome lattice, prepared hydrothermally, is found to exhibit magnetic hysteresis like a ferrimagnet besides the characteristics of a frustrated system, like those of a spin glass.
Based on an isothermal, isobaric simulation the structure and properties of the plastic crystalline phases of C60 and neopentane have been examined. Instantaneous cooling of the plastic crystalline phases of both C60 and neopentane leads to orientational glassy phases. These are accompanied by significant slowing down of reorientational motion. Constant pressure quench experiments on C60 yield a glass transition temperature of around 80 K.
No abstract is provided for this article.
No abstract is provided for this article.
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Null- und eindimensionale Metallcarboxylate wandeln sich in höherdimensionale Strukturen um (siehe Bild). Dahinter steckt ein progressiver Aufbauprozess, der die Möglichkeit bietet, die Synthese solcher Verbindungen zeitlich zu steuern.
No abstract is provided for this article.
Several (La1−y Lny)2−x Srx(Bax)CuO4 systems show superconductivity in the 15–40K region. Marginal metallicity of the non-superconducting phases and the role of the nominal Cu3+ /Cu 2+ ratio are discussed. Possible importance of hole-hole coupling (forming resonating O-O bonds) is indicated.
Chemical approaches have emerged as the preferred means to synthesize nanostructures of various inorganic materials due to superior control over size, shape, and surface functionality. This article provides an overview of the contributions made in the authors' laboratory toward the synthesis of nanocrystals, nanowires, nanotubes, nanowalls, and other nanostructures of several inorganic materials. Thus, thiolized monodisperse metal nanocrystals have been obtained by a ligand exchange process and the stability of their 2D assemblies studied. Nanocrystals of pure CoO and ReO 3 have been synthesized, for the first time, employing a one-pot solvothermal technique. The solvothermal method has also been used to obtain organic soluble nanocrystals of semiconducting materials such as CdS, CdSe, and GaN. Inorganic nanowires and nanotubes have been prepared by several soft chemical routes, including surfactant-assisted synthesis and hydrogel templating. A simple reaction between elemental Se and Te with NaBH 4 in water has been utilized to obtain nanowires of Se and Te. We also describe the nebulized spray pyrolysis (NSP) technique to synthesize carbon nanotubes and nanowires of metals and III-V nitride semiconductors with improved yields. An important new technique for preparing nanocrystalline films of materials is by the reaction of the metal precursors in the organic layer at the interface of two immiscible liquids, with appropriate reagents. Nanocrystalline films of metals, alloys, and semiconductors and ultra-thin single-crystalline films of metal chalcogenides and oxides have been obtained by this technique. Apart from these, we discuss single precursor routes to iron sulfide, GeSe 2 , and III-V nitride nanostructures as well as the first synthesis of GaS and GaSe nanowalls and nanotubes obtained through exfoliation by laser irradiation and thermal treatment.
No abstract is provided for this article.
Infrared spectra of substituted benzoyl chlorides and benzoyl bromides have been studied. The extent of splitting of the carbonyl band in benzoyl chlorides varies with substitution. While benzoyl bromide shows the carbonyl band as a single peak, para-nitrobenzoyl bromide shows a doublet. The results are interpreted in terms of intramolecular vibration effects (Fermi resonance). The intense band in the 860–880 cm−1 region in benzoyl chloride and benzoyl bromide has been assigned to the Ph-C stretching vibration.
