Development of Crystalline Cu2S Nanowires via a Direct Synthesis Process and Its Potential Applications

Large-scale and uniform copper(I) sulfide (Cu₂S) nanowires have been successfully synthesized via a cheap, fast, easily handled, and environmentally friendly approach. In addition to the reductive properties of the biomolecule-assisted method, they also have a strong shape- or size-directing functionality in the reaction process. The field-emission properties of the Cu₂S nanowires in a vacuum were studied by the Folwer–Nordheim (F–N) theory. The Cu₂S nanowires have a low turn-on field at 1.19 V/μm and a high enhancement factor (β) of 19,381. The photocatalytic degradation of Cu₂S nanowires was investigated by the change in the concentrations of rhodamine B (RhB) under UV illumination. These outstanding results of Cu₂S nanowires indicate that they will be developed as good candidates as electron field emitters and chemical photocatalysts in future nanoelectronic devices.

Synthesis and self-assembly of partially sulfonated poly(arylene ether sulfone)s and their role in the formation of Cu2S nanowires

Partially sulfonated poly(arylene ether sulfone)s was synthesized by one-step S_NAr copolymerization and self-assembled into spherical micelles in aqueous solutions, which assisted formation of Cu₂S nanowires on various substrates.

Synthesis and properties of semiconducting iron pyrite (FeS2) nanowires

We report the growth and structural, electrical, and optical characterization of vertically oriented single-crystalline iron pyrite (FeS(2)) nanowires synthesized via thermal sulfidation of steel foil for the first time. The pyrite nanowires have diameters of 4-10 nm and lengths greater than 2 μm. Their crystal phase was identified as cubic iron pyrite using high-resolution transmission electron microscopy, Raman spectroscopy, and powder X-ray diffraction. Electrical transport measurements showed the pyrite nanowires to be highly p-doped, with an average resistivity of 0.18 ± 0.09 Ω cm and carrier concentrations on the order of 10(21) cm(-3). These pyrite nanowires could provide a platform to further study and improve the physical properties of pyrite nanostructures toward solar energy conversion.

Evolution of hierarchical hexagonal stacked plates of CuS from liquid-liquid interface and its photocatalytic application for oxidative degradation of different dyes under indoor lighting

Blue solution of copper(II) acetylacetonate complex, [Cu(acac)(2)] in dichloromethane (DCM) and an aqueous alkaline solution of thioacetamide (TAA) constitute a biphasic system. The system in a screw cap test tube under a modified hydrothermal (MHT) reaction condition produces a greenish black solid at the liquid-liquid interface. It has been characterized that the solid mass is an assembly of hexagonal copper sulfide (CuS) nanoplates representing a hierarchical structure. The as-synthesized CuS nanoplates are well characterized by several physical techniques. An ethanolic dispersion of CuS presents a high band gap energy (2.2 eV) which assists visible light photocatalytic mineralization of different dye molecules. Thus a cleanup measure of dye contaminated water body even under indoor light comes true.

Solution-phase template approach for the synthesis of Cu2S nanoribbons

In this paper, we have developed a solution-phase template approach to synthesize Cu(2)S nanoribbons for the first time. Bi(2)S(3) nanoribbons act as both template and reactant when treated with small CuCl particles, generating Cu(2)S nanoribbons with the assistance of the solvent ethanol. Nanoribbons with different compositions of Bi(2)S(3) and Cu(2)S also could be obtained through controlling the reaction time. This kind of template method is expected to be a general template approach due to its slow reaction rate and simplicity.

Controlled Growth of Large-Area, Uniform, Vertically Aligned Arrays of α-Fe2O3 Nanobelts and Nanowires

Vertically aligned iron oxide nanobelt and nanowire arrays have been synthesized on a large-area surface by direct thermal oxidation of iron substrates under the flow of O(2). The effects of reactive gas pressure, composition, and temperature have been systematically studied. It was found that nanobelts (width, tens of nanometers; thickness, a few nanometers) are produced in the low-temperature region (approximately 700 degrees C) whereas cylindrical nanowires tens of nanometers thick are formed at relatively higher temperatures (approximately 800 degrees C). Both nanobelts and nanowires are mostly bicrystallites with a length of tens of micrometers which grow uniquely along the [110] direction. The growth habits of the nanobelts and nanowires in the two temperature regions indicate the role of growth rate anisotropy and surface energy in dictating the ultimate nanomorphologies.

Controlled reactions on a copper surface: synthesis and characterization of nanostructured copper compound films

We report the synthesis of nanostructured copper compound films on a copper surface under mild conditions. A series of low-dimensional structures including Cu(OH)(2) fibers and scrolls, CuO sheets and whiskers, and Cu(2)(OH)(2)CO(3) rods have been successfully grown on the copper surfaces at ambient temperature and pressure. Most of the structures are phase-pure single crystallites. The films were formed by the direct oxidation of copper in aqueous solutions of NaOH with an oxidant (NH(4))(2)S(2)O(8). The evolution of the ultrafine structures as a function of the reaction conditions has been revealed, from fibers of Cu(OH)(2) to scrolls of Cu(OH)(2) to sheets or whiskers of CuO. By replacing NaOH with NaHCO(3) in the synthesis, square/rectangular rod arrays of Cu(2)(OH)(2)CO(3) were obtained. The controlled reactions allow the large-scale, template-free, cost-effective synthesis of copper compound films with ordered, uniform, stable, ultrafine structures.