CuS Microspheres Research Articles

Amylose-directed synthesis of CuS composite nanowires and microspheres

Reported are the synthesis and characterization of CuS composite nanowires and microspheres in the presence of amylose. The preparation involved first the complexation of amylose with Cu2+ of CuCl2 at 70°C. Cu2+ complexation was confirmed by a conductivity reduction of CuCl2 after amylose addition. Also, the aggregation state of the amylose changed after Cu2+ as revealed by transmission electron microscopy (TEM) and dynamic light scattering (DLS). At the Cu2+ to α-d-glucopyranosyl unit molar ratio r of 0.70 and 1.41, the amylose aggregated into microspheres that were approximately 150 and 250nm in diameter. Adding sodium thiosulfate resulted in the production of an amorphous precipitate consisting presumably of CuS2O3. At r=0.70 and 1.41, CuS2O3 precipitated inside the template of Cu2+/amylose microspheres as nanoparticles, while a twisted nanowire-like structure was produced at r=0.92. CuS2O3 decomposed under heating at 100°C to yield crystalline CuS nanoparticles.

Growth Mechanism and Characterization of Porous CuS Microspheres

In this paper, a facile method was presented to fabricate CuS porous microspheres, which were formed by the intergrowth of CuS polycrystalline nanoslices. The obtained sample has been characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), selected area electronic diffraction (SAED), and scanning electron microscopy (SEM). On the basis of the experimental results, we proposed a self-assemble mechanism to elucidate the formation of CuS nanoslice structure.

Preparation of CuS Hollow Microsphere by a Simple Hydrothermal Method and its Catalytic Property

A simple method was applied to fabricate phase-pure hollow CuS microspheres. The obtained product was characterized by X-ray diffraction, scanning electron microscopy, photoluminescence spectra and UV-Vis absorption spectroscopy. Further, the catalytic activity of CuS spheres was evaluated by the decolorization of Rhodamine B in the presence of hydrogen peroxide solution at room temperature. The results indicated that the product showed a good optical propertie, and the hollow sphere CuS could be an effective catalytic material.

Synthesis of Flower-Like CuS Nanostructured Microspheres Using Poly(ethylene glycol) 200 as Solvent

CuS flower-like microspheres with the diameter of about 3-4 microm constructed by nanoflakes with thickness of about 30-40 nm have been successfully synthesized by a simple wet chemical method. In this reaction system, Poly(ethylene glycol) 200 (PEG 200) was used as solvent, CuCl2 2H2O as cuprum source, and thioacetamide (TAA) as sulfur source. The products were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), and high-resolution transmission electron microscopy (HRTEM) in detail. The XRD patterns revealed that the products were pure hexagonal phase of CuS. Experiments with various parameters indicated that the reaction temperature and molar ratio of CuCl2 2H2O to thioacetamide had strong effects on the sizes and morphologies of CuS crystals. A possible growth mechanism on the formation of CuS microspheres was proposed. The PEG 200 acted as solvent, complexing agent, and soft template in this synthesis. Furthermore, optical studies of the products including UV-Vis absorption spectrum and photoluminescence spectrum have also been carried out.

Controlled synthesis of various hierarchical nanostructures of copper sulfide by a facile microwave irradiation method

Hierarchical flower-like spheres and self-assembled chains of copper sulfide have been synthesized by a facile microwave irradiation. The as-obtained products were characterized by means of X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), selected area electron diffraction (SAED), and energy-dispersive X-ray spectroscopy (EDX), Fourier transform infrared (FTIR) spectroscopy. The SEM and TEM results showed that three-dimensional (3D) flower-like CuS spheres are constructed by a number of two-dimensional (2D) nanosheets as primary building units, whereas the one-dimensional (1D) hierarchical chains are formed by the oriented attachment of the 3D flower-like spheres of CuS. The influences of the additive EDTA, concentration of reactants, microwave power, and reaction time on final morphology and assembled structure of the products were systematically investigated. On the basis of our experimental results, a phenomenological elucidation of the mechanism for the growth of the CuS architectures has been presented, and the driving force for the self-assembly of the nanoplates can be attributed to interfacial tension and the interaction between the hydrophilic surfaces of CuS nanoplates. EDTA acts as both a chelating reagent and a surface capping agent in the synthesis process. Moreover, the optical property of the flower-like CuS microspheres was measured by UV–vis absorption spectroscopy.

Direct electrochemistry of hemoglobin in a nafion and CuS microsphere modified carbon ionic liquid electrode and its electrocatalytic behavior

Direct electrochemistry of hemoglobin (Hb) was realized on a Nafion and CuS microsphere composite film modified carbon ionic liquid electrode (CILE) with N-butylpyridinium hexafluorophosphate (BPPF6) as binder. Scanning electron microscopy (SEM), UV-Vis absorption spectroscopy and cyclic voltammetry were used to characterize the fabricated Nafion/CuS/Hb/CILE. Experimental results showed that a pair of well-defined quasi-reversible redox peaks appeared with the formal potential as -0.386 V (vs. SCE) in pH 7.0 Britton-Robinson (B-R) buffer solution, which was attributed to the Hb heme Fe(III)/Fe(II) redox couples. The electrochemical parameters of Hb in the composite film were carefully investigated with the charge transfer coefficient (α), the electron transfer number (n) and the electron transfer rate constant (ks) as 0.505, 1.196 and 0.610 s -1 , respectively. The composite film provided a favorable microenvironment for retaining the native structure of Hb. The presence of CuS microspheres showed great improvement on the electron transfer rate of Hb with the CILE, which maybe due to the contribution of specific characteristics of CuS microspheres and the inherent advantages of ionic liquid on the modified electrode. The fabricated Hb modified electrode showed good electrocatalytic ability in the reduction of H2O2. The proposed bioelectrode can be used as a new third generation H2O2 biosensor.

Preparation and characteristics of porous CuS microspheres consisted of polycrystalline nanoslices

This paper presents a facile method to fabricate CuS porous microspheres, which were formed by the intergrowth of CuS polycrystalline nanoslices. The obtained sample has been characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), selected area electronic diffraction (SAED), X-ray diffraction (XRD), UV–vis diffusion reflection and Laser Raman. On the basis of the experimental results, we proposed a self-assemble mechanism to elucidate the formation of CuS nanoslice structure. The current–voltage characteristic under different gas atmospheres shows that the as prepared CuS polycrystalline nanoslices are sensitive to ammonia at ppm level and the electrical conductivity is found to be weaker in ammonia than that in air.

Synthesis of ZnS whiskers and their photoluminescence properties

ZnS whiskers were successfully synthesized by the chemical vapor deposition method with the assistance of CuS micro-spheres. The composition, morphology and structure of the samples were characterized by X-ray diffraction, X-ray energy dispersive spectroscopy, scanning electron microscopy, and the temperature-dependent photoluminescence (PL) spectrum over a temperature range from 10 to 250 K was studied. The results show that the as-synthesized ZnS whiskers have an average length of 0.3 mm and diameter of 2.5 μm with a cubic zinc-blende structure. There exist three emission bands in the blue, green and yellow regions, and the emission mechanism is discussed. As the temperature increases, the temperature-dependent PL spectrum shows anomalous behavior, where distinct inverted V-shaped characters of blue and green emission integrated intensity and an inconspicuous S-shape of blue emission peak energy are observed. The transition mechanism is discussed.

Self-assembly of CuS nanoflakes into flower-like microspheres: Synthesis and characterization

Using Cu(S 2CNEt 2) 2 as a single-source precursor and ethylamine solution (65–70%) as the reaction medium, large-scale flower-like CuS microspheres have been synthesized via a solvothermal treatment in the presence of a surfactant. The products were characterized by XRD, SEM, TEM, HRTEM, and UV-vis spectrum. The assembled microspheres, with a diameter of about 2–3 μm, were composed of single-crystalline hexagonal CuS nanoflakes with a thickness of several tens of nanometers. It was revealed that the solvent medium, the surfactant, and the reaction time have great influence on the morphology and size of the resulting CuS products.

Synthesis and characterization of tubular CuS with flower-like wall from a low temperature hydrothermal route

Tubular copper sulfide (CuS) microcrystal and flower-like CuS microsphere have been synthesized by simple hydrothermal route at 75°C using CuCl 2·2H 2O as Cu-precursor, C 2H 5NS as S-source and CTAB as the template. The effect of concentration of reactants and template molecules on morphology has been discussed. X-ray diffraction pattern suggests that the CuS crystals are pure hexagonal phase. The morphology of the products has been studied by scanning electron microscope analysis. The absorption peaks of CuS in UV and near-IR regions indicate that the as-prepared CuS are promising in the development of photoelectric devices.

Water-Induced Thermolytic Formation of Homogeneous Core−Shell CuS Microspheres and Their Shape Retention on Desulfurization

Homogeneous inorganic core−shell microspheres made from hexagonal CuS are synthesized via thermolysis of Cu(R2dtc)2 (R = octyl, dtc = dithiocarbamate) precursor at 130−180 °C under N2 flow, optimally at 180 °C for 0.5 h. Scanning electron microscopy (SEM) analyses indicate that the core−shell microspheres have an average diameter of 1.74 μm (σ = ±12.7%) with a shell thickness of about 225 nm. Their formation is induced by the small amount of water in the precursor. A tentative formation mechanism is speculated. Interestingly, the as-made cupric sulfide CuS microspheres undergo a reduction to tetragonal cuprous sulfide Cu2S microspheres without morphology changes via solid-state annealing at 400 °C under N2 atmosphere. The microspheres made over 400−700 °C are invariably tetragonal Cu2S phase.

Synthesis of hollow CuS nanostructured microspheres with novel surface morphologies

Hollow CuS nanostructured microspheres with novel surface morphologies were synthesized by a facile precipitate-converting reaction. The products were characterized by SEM, XRD, BET measurements and size analysis. The surfaces of the hollow CuS microspheres showed acicular, rod-like, concavo-convex and flat morphologies respectively when using different amounts of thioacetamide as precipitants. The diameters of the hollow CuS microspheres could be tuned to a certain extent by using Cu 2(OH) 2CO 3 microspheres with different sizes as precursors. A solid–solution–solid mechanism for the formation of the hollow CuS nanostructured microspheres was discussed. The method reported here also could be applied for the synthesis of other nanostructured microspheres.