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Cubic MnCO 3 @C composite was first synthesized using one-pot hydrothermal method. The prepared cubic MnCO 3 @C presented a homogeneous core-shell structure, which was composed of cubic MnCO 3 as core, a mixture of amorphous carbon and MnCO 3 as shell, and a separating interlayer. Compared to pure MnCO 3 , core-shell structured MnCO 3 @C exhibited better cycling stability, rate performance and recovery capability. It delivered a reversible capacity of 1020 mAh g −1 which was 94.7% of the initial capacity, and a recovery capacity of 862 mAh g −1 after 80 cycles under current density from 100 mA g −1 to 10000 mA g −1 . The superior electrochemical performance of MnCO 3 @C could be attributed to the improved electronic conductivity and suppressed particle aggregation during the conversion reaction. Voltage profile and cyclic voltammetry test results showed active material transformation in both anode materials during the cycling process. Furthermore, the infrared spectra at different discharge/charge states showed that the conversion reactions of MnCO 3 included not only the transition from MnCO 3 to Mn, but also a further reaction from Li 2 CO 3 to Li 2 O.

A special acanthosphere shaped FeCO 3 anode powder material was synthesized successfully through controlled hydrothermal method. It delivered an initial specific discharge-charge capacity of 2100/1087 mA h g −1 at a current density of 100 mA g −1 , and exhibited a high discharge capacity of 238 mA h g −1 even at a current of 10,000 mA g −1 . Furthermore, its capacity would return to the initial capacity level even if the discharge/charge current got back from 10,000 mA g −1 to 100 mA g −1 . Galvanostatic intermittent titration technique (GITT) method was used to investigate the lithiation mechanism of FeCO 3 electrode, and results showed that the lithium ion diffusion was driven by two step reactions, the first transition from FeCO 3 to Fe and the second reduction of newly grated LiCO 3 , respectively. High diffusion coefficients of Li ions also give the reason for the high capacity under large rate charge-discharge condition.

Mesoporous silica MCM-41 (MS-MCM-41) was synthesized via a hydrothermal treatment using sodium silicate as a silica source extracted from wheat straw ash. The effect of aging temperature to the structure and physical properties of the mesoporous silica was discussed to provide the optimum preparation technique. The more ordered 2D hexagonal structure of mesoporous silica was obtained by applying the hydrothermal treatment procedure. With increasing the hydrothermal aging temperatures from 80 °C to 120 °C, the pore volume and average pore size enlarged accordingly and the BET surface area increased from 724 to 1312 m2/g, respectively.

Monodispersed Fe 3 O 4 /PANI core–shell nanocomposites were synthesized by microemulsion polymerization. Before the polymerization of aniline, Fe 3 O 4 nanoparticles were prepared by thermal decomposition of iron acetylacetonate using benzyl alcohol as the solvent and were surface-modified by oleic acid. Then aniline monomer was polymerized on the surface of Fe 3 O 4 nanoparticles by microemulsion polymerization with sodium dodecyl benzene sulfonate as the surfactant and ammonium persulfate as the oxidant. Fourier transform infrared (FT-IR) spectra indicated that the oleic acid was chemisorbed on the surface of Fe 3 O 4 nanoparticles. Transmission electron microscopy (TEM) analysis showed that the oleic acid modified Fe 3 O 4 nanoparticles had a better dispersity with a diameter around 10 nm. The Fe 3 O 4 /PANI nanocomposites were monodisperse with Fe 3 O 4 as the magnetic core and PANI as the conductive shell. The as-prepared Fe 3 O 4 /PANI nanocomposites showed a superparamagnetic behavior. The paraffin composites with 70 wt.% Fe 3 O 4 /PANI powders provided good electromagnetic wave absorption performance (RL

PPy/TiO2 nanocomposites were successfully prepared by reverse microemulsion polymerization and used as an effective photocatalyst for the degradation of methyl orange. Titanium dioxide (TiO2) was modified by silane coupling agent to improve the dispersity before the polymerization. X-ray diffraction (XRD), transmission electron microscopy (TEM), and Fourier-transform infrared spectra were carried out to characterize the morphology and structure of the samples. TEM analysis shows that TiO2 particles are deposited by polypyrrole (PPy) and the existence of PPy mitigates the agglomeration of TiO2. XRD spectra reveal that the deposition of PPy does not change the structure of TiO2 particles. Uv–vis analysis shows that the PPy/TiO2 nanocomposites have a higher photocatalytic activity under natural light than neat TiO2. The highest degradation rate occurs when the mass ratio of PPy to TiO2 is kept at 0.02. POLYM. COMPOS., 34:1076–1080, 2013. © 2013 Society of Plastics Engineers

Nanostructured SnO 2 was prepared based on the sol–gel method. Aniline monomer was polymerized by microemulsion polymerization in the presence of nanocrystalline SnO 2 to form inorganic–organic nanocomposite materials, in which SnO 2 nanoparticles were embedded within porous polyaniline (PANI). Structural and morphological characterization of SnO 2 and SnO 2 /PANI was carried out using X-ray diffraction (XRD), Fourier transform infrared (FT-IR), transmission electron microscopy (TEM) and scanning electron microscopy (SEM). The XRD pattern suggested that PANI did not modify the crystal structure of SnO 2 . FT-IR spectrum proved that aniline was successfully composited with the nanostructured SnO 2 . TEM analysis showed that the SnO 2 nanoparticles with a diameter of ca. 15 nm were embedded well in the porous PANI. Conductivity analysis indicated that the SnO 2 /PANI nanocomposites had a higher conductivity than that of the pure SnO 2 nanopowders.

Electrically conductive polypyrrole (PPy)/poly(methyl methacrylate) (PMMA) core-shell nanoparticles were synthesized by two-step microemulsion polymerization. PPy core particles were prepared in a four-component microemulsion system, which was formed with surfactant cetyltrimethyl ammonium bromide (CTAB), cosurfactant n-pentanol, water, and pyrrole. Ferric chloride and iodine was added as the oxidant and the dopant, respectively. Then the PPy nanoparticles were coated with PMMA to prepare PPy/PMMA core-shell nanoparticles. The morphology of PPy/PMMA core-shell nanoparticles was characterized with transmission electron microscopy (TEM). Fourier transform infrared (FTIR) spectroscopy was used to characterize the structure of the samples. The electrical conductivities of samples were studied by a Hall effect testing instrument. Despite being coated with a layer of insulation, the conductivity of the composite PPy/PMMA core-shell nanoparticles could still reached to 7.856 × 10−1 S/cm.

In this article, the microparticles of polystyrene-poly(styrene-co-sodium 4-styrenesulfonate) (PS-PSS) coated by polyaniline (PANI) were prepared and hollow PANI microspheres were further obtained by dissolving the core. First, surface-sulfonated monodispersed PS was prepared by copolymerization of sodium 4-styrenesulfonate (SSS) and styrene with dispersion polymerization method. Then aniline was polymerized on the surface of the surface-sulfonated PS (PS-PSS) by chemical oxidative polymerization. After purification, we prepared core-shell (PS-PSS)/PANI particles. Hollow PANI microspheres were prepared by dissolving the plastic PS core of the (PS-PSS)/PANI particles in chloroform. The growth process of PANI on the surface of PS-PSS particles was investigated and the hollow PANI microspheres were characterized. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012

A microemulsion polymerization method to synthesize polypyrrole/Au nanocomposites by direct oxidation of pyrrole using HAuCl 4 as the oxidant is presented. Sodium dodecyl sulfate and n-pentanol is used as the surfactant and the cosurfactant, respectively. The obtained nanocomposite particles have a tetrahedron structure, where Au dispersed as ultra-small clusters of elementary gold are encapsulated by polypyrrole. The morphologies and structures of the nanocomposites have been characterized by high-resolution transmission electron microscopy, transmission electron microscopy, X-ray diffraction, and UV–Vis spectroscopy. Conductivity analysis shows that the conductivity of polypyrrole/Au nanocomposites is 12.6 ± 0.06 S/cm.

The silica/polypyrrole core-shell composites were fabricated by in situ chemical polymerization of pyrrole monomer on the surface of the silica spheres. Silica sol particles with narrow size distributions were prepared by hydrolysis of tetraethoxysilane with sol–gel method. Polypyrrole shell was obtained by chemical polymerization of pyrrole monomer on the surface of the silica spheres in the water–ethanol mixture. It can be seen from the experiment, with the adding of small amount of ethanol cosolvent to the aqueous reaction solution, a uniform coating of polypyrrole appeared on the surface of silica. The core-shell morphology of composite particles prepared with variation ethanol adding amount was analyzed by TEM. Meanwhile, the conductivity of the core-shell composite is found to be enhanced apparently compared with those prepared from pure aqueous system. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012

Conductive polymer particles, polyaniline (PANI)-coated poly(methyl methacrylate–butyl acrylate–acrylic acid) [P(MMA–BA–AA)] nanoparticles, were prepared. The P(MMA–BA–AA)/PANI core–shell complex particles were synthesized with a two-step miniemulsion polymerization method with P(MMA–BA–AA) as the core and PANI as the shell. The first step was to prepare the P(MMA–BA–AA) latex particles as the core via miniemulsion polymerization and then to prepare the P(MMA–BA–AA)/PANI core–shell particles. The aniline monomer was added to the mixture of water and core nanoparticles. The aniline monomer could be attracted near the outer surface of the core particles. The polymerization of aniline was started under the action of ammonium persulfate (APS). The final product was the desired core–shell nanoparticles. The morphology of the P(MMA–BA–AA) and P(MMA–BA–AA)/PANI particles was characterized with transmission electron microscopy. The core–shell structure of the P(MMA–BA–AA)/PANI composites was further determined by Fourier transform spectroscopy and ultraviolet–visible measurements. The conductive flakes made from the core–shell latexes were prepared, and the electrical conductivities of the flakes were studied. The highest conductivity of the P(MMA–BA–AA)/PANI pellets was 2.05 S/cm. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012

In this paper, amorphous hydrated silica in Gramineae plant, named as phytoliths, was extracted and investigated from wheat straw. Porous nano-structured silica was prepared from agricultural waste materials through combustion and acid leaching. The results show that: i) the phytoliths in epidermal cells of wheat straw are round with a diameter of 14–22 μm, while those in trachea are oblong with a length of 18–40 μm and a width of 12–18 μm. These different phytoliths are all core–shell structures with the silica shell and the organism core of the plant cells; ii) The distribution of particle size, surface area, pore diameter and pore volume of nano-structured silica samples decreases with the increase of calcining temperature, and at a higher temperature, some agglomerates are formed. The results of this work are useful for scientists pursuing new synthetic route for valuable and widely applicable nanoscale silica materials, also helping to solve disposal and pollution problems.

Electrically conductive core–shell nanoparticles (PANI/PS-PSS) were synthesized by coating poly (styrene-co-styrene sulfonate) (PS-PSS) nanoparticles with polyaniline (PANI). PS-PSS core particles were prepared in microemulsion system in nitrogen atmosphere and further coated with PANI by using in situ polymerization method at low temperature. The core–shell structure of PANI/PS-PSS composites was determined by transmission electron microscopy (TEM) and FTIR measurements. In addition, the role of the aniline content was also investigated. The stability of the coated latexes and the conductivity of PANI/PS-PSS pellets were investigated. It was found that the core–shell structure of PANI-coated PS-PSS can be obtained when PANI in PANI/PS-PSS copolymer varies from 2.78 to 12.5 wt%. The highest conductivity of PANI/PS-PSS pellets is 1.7 S/cm.

Large quantities of CdS nanowires were successfully synthesized through a one-step poly (ethylene glycol)-assisted solvothermal route. The nanowires obtained were characterized by XRD, SEM, TEM, HRTEM, UV-vis and PL. The single crystalline nanowire is uniform in morphology with a [001] growth direction. Optical properties measurement reveals the quantum confinement effect of the CdS nanowires. Based on the comparative experimental results, a possible growth mechanism of CdS nanowires was proposed that the formation of CdS nanowires was controlled by the number of CdS nucleus at the initial reaction stage. The applicability of the growth mechanism for CdS nanowires was further verified by substituting poly (vinyl alcohol) for poly (ethylene glycol).

An effective solvothermal reaction route has been developed for large-scale synthesis of CdS nanowires. L-cysteine was used as both sulfur source and capping reagent. The nanowires obtained were characterized by XRD, SEM, TEM, HRTEM, UV-Vis and PL. On the basis of time-resolved experiments, a possible growth mechanism was proposed. FTIR analysis confirmed the formation of Cd-cysteine complex and peptide during the reaction. The mechanism was further supported by comparative experiments with other sulfur sources.

Single crystalline α-Fe 2 O 3 cubic particles of narrow size distribution were prepared by a hydrothermal synthesis at 130 °C from a solution of urotropine ((CH 2 )N 4 ) and ferric chloride. About 400 nm faultless cubic particles were observed. Spheres with rough surface were synthesized at 80 °C, while pseudo cubes and some spheres were prepared at 100 °C. For the preparation of α-Fe 2 O 3 cubes, 130 °C is the appropriate temperature.

Single crystalline ZnO nanorods were prepared by the hydrothermal method with synthesized ZnCl2·4Zn(OH)2 as the precursor. Morphologies of the nanorods were controlled by various reaction conditions with cetyltrimethylammonium bromide (CTAB) as the modifying agent. The nanorods were characterized by XRD, TEM, UV-Vis spectra, and IR spectra. The microstructure of holes in nanosize was observed on the surface of the nanorods. The UV-Vis spectra indicate that the as-prepared ZnO nanorods have absorption of visible-light as well as ultraviolet-light. Therefore, these nanorods may be good candidates for visible-light photocatalysis materials from the viewpoint of practical applications. The reason for visible-light absorption was discussed in this article.

Single crystalline ZnO nanorods were achieved by the assembly of nanocrystallines in tens of nanometer under hydrothermal conditions with the assistance of surfactant cetyltrimethylammonium bromide (CTAB). The obtained nanorod has rough surface as a result of oriented attachment growth. Transmission electron microscope (TEM) images showed the morphology evolution of the nanorod at different reaction time. Defects were observed and porous structure was left after the assembly of hundreds of nanocrystalline building blocks. Effect of pH condition on the morphology of the nanorod was also investigated.

Based on the method of bridging coordinated precursor, pure and Cu, Rh doped tin oxide have been synthesized in order to investigate the influence of metal doping and multi-metal doping on the microstructure and optical properties of the host material. We attest to the formation of a chain-like precursor by FTIR analysis. All the studied systems were characterized by XRD, TEM/HRTEM and UV-VIS. Although Cu doping has few effects on the microstructure, it improves the optical properties of the host material. However Rh doping can apparently affect both the microstructure and the optical property. In the co-doped system, Cu doping reduces the effectiveness of Rh doping greatly.

The kinetics of microemulsion copolymerization of styrene and acrylonitrile in oil-in-water microemulsions in the presence of n-butanol as a cosurfactant was investigated. Stable and translucent poly(styrene-co-acrylonitrile) latexes were produced. The variations of initiator concentration, polymerization temperature, monomer feed composition and cosurfactant concentration in the microemulsion copolymerization were studied. In addition, the particle size and molecular weights of copolymerization products were characterized. It was found that the rate of copolymerization decreases pronouncedly and the maximum rate was shifted to a lower conversion with an increase of AN concentration in the monomer feed. The presence of n-butanol can lead to a decrease in polymerization rate and an increase in particle size, but a complex effect on the molecular weight of the copolymer. The obtained experimental results were discussed in terms of the nucleation mechanism, the agglomeration of particles and the effect of microemulsion structure.

Nickel oxide (NiO) nanowire was synthesized by a simple aqueous solution method with urea as precipitant. The structure, morphology and properties of the products were examined by X-ray diffraction (XRD), transmission electron microscopy (TEM), infrared absorption spectra (IR), and UV–visible absorption spectra. The results of the electrical and optical measurements made on these nanowire are discussed. The TEM images show the calcination product is NiO polycrystalline nanowire with diameters 5–15 nm. Thermal stability of this nanowire was studied by calcining the precursor at different temperatures and the breakdown of the precursor nanowire was observed after being calcined at 600 °C for 2 h.

The SnO2 sub-microrod arrays have been fabricated by using PVA-assisted solvothermal method in our experiment for the first time. The analyses of XRD, TEM and SAED show the existence of face-centered cubic phase SnO2 in the as-prepared sub-microrod structures. In addition, the comparative study of the as-prepared and 800°C calcined SnO2 sub-microrod arrays also attests the recrystallizing process between cubic and rutile phase. This phase transition begins at 391.0°C and accomplishes at 448.3°C. By DLA pattern, we proposed a self-assemble model for Sn4+ precipitation on PVA ‘seed’ template to explain the mechanism of SnO2 sub-microrod growth.

The microemulsion copolymerization of styrene and acrylonitrile in an n-butanol/cetyltrimethylammonium bromide/oil/water microemulsion system was studied. The solubilization sites of the two monomers were determined with an NMR technique. The results showed that the solubilization behaviors of the two monomers were quite different. Most of the styrene was solubilized in the palisade layer of the microemulsion, whereas the acrylonitrile had an equilibrium distribution in the aqueous phase and palisade layer of the microemulsion. The reactivity ratios of styrene and acrylonitrile in the microemulsion system were different from those in other media. The effect of the monomer feed composition on the copolymerization kinetics was investigated, and the mechanism of nucleation of the latex particles was examined. The experimental results showed that the copolymerization loci were changed from the microemulsion droplets to the aqueous phase when the concentration of acrylonitrile in the monomer feed reached approximately 80%; this could be further proved by the effect of the monomer feed composition on the copolymerization kinetics. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 203–216, 2005

An epoxy resin (E-51)-modified acrylic–polyurethane emulsion with triethylenetetramine (TETA) serving as the postcrosslinking agent was synthesized. The curing reaction between E-51 and the curing agent TETA during the film-forming course was monitored and identified by an infrared spectrophotometer. The stabilities of the single-pack emulsion during the polymerization course as well as the storage stage were investigated. The effect of the epoxy resin was studied in terms of the dispersion size of the emulsion, the mechanical properties, as well as the swell in water and toluene of the cast film, The emulsion was shown to be stable when the epoxy content was below 20% based on the mass of the polyacrylate in the system. The tensile strength and the modulus and the water and toluene resistance were enhanced with increase of the epoxy resin. In contrast, the elongation at break was decreased. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 470–475, 2003

The role of ammonium polyacrylate (NH4PAA) in the dispersion of nanosized titanium dioxide (TiO2) was investigated experimentally. The adsorption of NH4PAA onto TiO2 has been studied as a function of pH. The adsorption amount of NH4PAA was found to decrease with increasing pH. With increasing NH4PAA concentration, the isoelectric point for nanosized TiO2 particles shifts from pH 5.9 to 2.7. The addition of NH4PAA leads to a lower viscosity in highly concentrated suspensions, and the rheological behavior of the TiO2 suspensions is strongly dependent on the amount of NH4PAA adsorbed.

This study reports a novel series of silicone‐based polyurethane (PU) surfactants by synthesized the addition polymerization of toluene diisocyanate to α,ω‐hydroxy polydimethylsiloxane, polyethylene glycol, and methanol. Their chemical structure was characterized by using Fourier transform infrared analysis. The prepared polymer's surface‐active properties in aqueous solution were investigated including surface tension, foaming, and wetting abilities. The results show this silicone‐based PU surfactants are fully water‐soluble and exhibit excellent surface‐active properties.

Phase diagrams of sodium dodecyl sulfonate (DS)/n‐butanol/styrene/water systems with variable amounts of styrene were constructed at 40°C, and the effects of styrene on microemulsion stability were studied. The solubilization of styrene in these O/W microemulsion systems was investigated by 1H NMR methods. The results show that the solubilization site shifts from the palisade layer to the inner core of microemulsion droplets when the molar fraction of styrene reaches 0.312. The solubilization of acrylamide in cetyltrimethylmethyl ammonium bromide (CTAB)/n‐butanol/10% n‐octane/water reverse microemulsions (W/O) was studied with a 13C NMR method. It was found that the acrylamide was mainly solubilized in the Stern layer of droplets at low acrylamide levels. However, when the mole fraction of acrylamide approaches 0.428, the acrylamide penetrates into the palisade layer and is distributed along the hydrocarbon chain of the surfactant.

The Al90Fe5Ce5 and Al83Zn10Ce7 alloys were analysed with the aim of studying the microstructural evolution under various processing conditions. In addition to the icosahedral phase surrounded by the Al phase, the fine scale distribution of the metastable Al6Fe phase produces on annealing the amorphous Al90Fe5Ce5 alloy. In Al83Zn10Ce7 alloy, the stable intermetallic compound Al2ZnCe2 forms as the primary phase during solidification. The precipitation nanocrystals of Al were accompanied with the intermetallic compound Al2ZnCe2. For the amorphous Al-based alloys, the high glass formation appears to be controlled largely by the suppression of growth of nuclei formed during rapid melt quenching. The competitive nucleation and growth limitation of the various phases are attributed to the complex microstructures characteristic of the Al-based alloys.

Isothermal and non-isothermal differential scanning calorimetry experiments were carried out to study rapidly solidified Al90Fe5Ce5 alloy. Microstructural analysis suggests that icosahedral nanoparticles are homogeneously distributed in the matrix of annealed amorphous Al90Fe5Ce5 alloy. The presence and homogeneous distribution of icosahedral structure units and icosahedral short-range domains appear to be critical for the formation and stability of the amorphous phase.