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Size- and surface-tunable carbon spheres loaded with iron-oxide (α-Fe2O3 or Fe3O4) nanoparticles have been obtained from 4-ferrocenyl-butyric acid via an easy one-step method in a solvothermal system. The composites obtained have been fully characterized by X-ray powder diffraction, scanning and transmission electron microscopy, Fourier transform infrared spectrometry, Raman spectrometry and vibrating sample magnetometry. The results show that the diameters and morphologies of the spheres can be tuned by adjusting the experimental parameters including the reaction temperature, time, medium, and precursor concentration. Most of the iron-oxide nanoparticles are evenly distributed on the surface of the carbon spheres and also the surface of the iron-oxide-loaded carbon spheres has large numbers of functional groups. The α-Fe2O3-loaded carbon spheres show special magnetic properties with a coercivity of 101.5 Oe and a remanent magnetization of 0.203 emu/g at room temperature, while the coercivity and remanent magnetization for the Fe3O4-loaded carbon spheres are 58.4 Oe and 0.174 emu/g, respectively. A possible formation mechanism is proposed and discussed based on the features of the reaction system.

Novel hierarchical layer-by-layer self-assembled one-dimensional (1D) La(OH)CO3 nanostructures, with a diameter of around 700 nm and lengths in the range of 6−8 μm, were synthesized by a developed hydrothermal method using La2O3 and glycine as the starting materials. Various experimental conditions, such as the reaction time, temperature, and the molar ratios of the starting reagents, were studied. The obtained 1D La(OH)CO3 nanostructures can be successfully converted to La2O3 and La(OH)3 nanorods via calcination under appropriate conditions. Analytical methods such as X-ray diffraction, scanning electron microscopy, transmission electron microscopy, and selected area electron microscopy were employed to characterize these products, and the possible growth mechanism of 1D La(OH)CO3 nanostructures was explored. The UV−visible diffuse reflectance absorbance spectra indicate that the 1D nanostructures have enhanced UV-light absorbance properties in contrast to the bulk materials. The electrochemical studies ...

Fabrication techniques for Test Blanket Module (TBM) with CLAM are being under development. Effect of surface preparation on the HIP diffusion bonding joints was studied and good joints with Charpy impact absorbed energy close to that of base metal have been obtained. The mechanical properties test showed that effect of HIP process on the mechanical properties of base metal was little. Uniaxial diffusion bonding experiments were carried out to study the effect of temperature on microstructure and mechanical properties. And preliminary experiments on Electron Beam Welding (EBW), Tungsten Inert Gas (TIG) Welding and Laser Beam Welding (LBW) were performed to find proper welding techniques to assemble the TBM. In addition, the thermal processes assessed with a Gleeble thermal-mechanical machine were carried out as well to assist the fusion welding research.

V 3 O 7 ·H 2 O nanoribbons and V 3 O 7 nanoflowers are firstly obtained via facile oxides-hydrothermal (O-HT) route. V 2 O 5 bulk-phase powder is directly used as precursor. The 1:1 ethanol/water and absolute ethanol are made as solvent for obtaining nanomaterials of vanadium oxides with different morphologies and structures. Characterizations of the samples are carried out using XRD, TG, FTIR, Raman-Spectra, SEM, TEM, HRTEM, SAED, and UV–vis. The large-scale fine ribbon-like V 3 O 7 ·H 2 O nanobelts with thickness ca. 20 nm and length ca. 20–40 μm are obtained in 1:1 (v/v) ethanol/water mixed solvent. The V 3 O 7 nanoflowers are constructed by numerous whisker-like nanocrystal or petal-like are obtained in absolute ethanol solvent with the thickness about 20 nm and the size ca. 2–3 μm. The formation mechanism of the sample is discussed.

BaWO 4 crystals with various morphologies had been synthesized via a biominmetic system of supported liquid membrane in the presence of different additive reagents at room temperature. The X-ray diffraction patterns showed that the obtained BaWO 4 crystals were tetragonal structure. Scanning electron microscopy results of the samples revealed that additive reagents and reacting time could highly affect the morphology and size of BaWO 4 crystals. In fluorescence spectra, there was an excellent blue-shift of luminescence. The growth processes of BaWO 4 crystals with different morphologies were investigated and a possible growth mechanism was discussed.

Two-dimensional handkerchief-like nanostructures of Ni and NiCo magnetic amorphous alloys have been synthesized by a double composite structure-inducing template. High resolution transmission electron microscopy was used to characterize the morphology and the dimensions. The self-assembly of fine handkerchief-like Ni and NiCo nanoalloys is attributed to the cooperation between ion-selected delivery of a hard collodion membrane by nitro-group chemical complexations and the size-controlled action of a reverse microemulsion. Importantly, the coordinations of ethylenediamine with Ni2+ and Co2+ can restrict the structure-inducing action. The phase transformation behavior was recorded by differential scanning calorimetry. Substituting Co for Ni can slow phase transformation, and the kinetic ordering temperature increases with the Co concentration increasing. The magnetic property measurement results show that the saturation magnetizations increase as the Co concentration is increased, but the coercivity is not ...

The electrochemical behaviors of ferulic acid were investigated at the glassy carbon electrode modified with multi-walled carbon nanotube. In pH 5.5, 0.1 mol l−1 HAc-NaAc buffer solution, ferulic acid exhibited a pair of stable and sensitive redox signals at the modified electrode. The reaction mechanism was explored. Through the cyclic voltammetry, trace amount of ferulic acid was detected quantitatively. In the range of 1 × 10−5 to 5 × 10−3 mol l−1, the oxidation peak currents of ferulic acid have a linear relationship to the concentrations, the limit of detection was estimated to be 1 × 10−7 mol l−1 (S/N = 3). The influences of substrate, pH and interference of coexisting substances were investigated for response properties of the electrode. Actual Xiao Yao Pill samples were analyzed and satisfactory results were obtained, which meant that the method could be used to detect the trace amount of ferulic acid in medicament.

Dumbbell-like nanosuperstructures of (3-carboxy-1-acyl-propyl)-ferrocene were successfully prepared by ultrasonic–pHcontrolling–reprecipitation method. The scanning electron microscope shows that as-obtained products were composed of nanorods. The length of the products is about 6–12 μm, the diameter of the two polar coronas and the middle part (waist) are respectively about 2–8 μm and 0.5–2 μm. The diameter of the nanorods that are the basic unit of the superstructures, is about 0.3 μm. X-ray diffraction analysis of the products indicated that the superstructures keep original crystal structure. The optical properties of the products were characterized by FT-IR spectrometer and UV spectrometer, and they display quantum size effect. This paper provides a novel method that has potential application in preparing other organometallic compounds superstructures, and more importantly, the as-obtained superstructures have widely applications. The possible mechanism was also proposed.

The electrochemical responses of phenols can be enhanced effectively by using surfactants at the glassy carbon electrode. The enhancement of surfactant, including cetyl trimethyl ammonium bromide and cetyl pyridinium chloride, on trinitrophenol, 2,4-dinitrophenol, 2,5-dinitrophenol, o-dihydroxy-benzene, p-dihydroxy-benzene, 1-naphthol, 2-naphthol and triphenol has been investigated in HAc–NaAc buffer solution, and most of the results are reported first. The interaction mechanism among the electrode, surfactant and detected phenols was studied comprehensively and two mechanism models were suggested. One is electrostatic effect model and the other is hydrogen bond model. The optimal conditions, such as pH value, concentration of surfactant used, were also studied in detail. For ionized phenols, the optimal concentration of surfactant added was 1.0 × 10−4 mol L−1, which was well below the critical micelle concentration. For nonionized phenols, the respective value was 1.2 × 10−3 mol L−1, which was close to the critical micelle concentration. All of the results obtained will be of great significance to the determination of phenols and substituted phenols.

Thermophilic bacterial strains HEN-Qn1 were incubated at 60 °C in a solution containing calcium chloride. With slow release of CO2 metabolic end products from the bacteria, CaCO3 nanomaterials were found after 12 h through a transmission electron microscope (TEM). CaCO3 nanorods were obtained extracellularly, whereas a unique morphology of nanosphere was observed intracelluarly. A single crystal was further characterized by electron pattern (ED) and X-ray powder diffraction (XRD). Moreover, a putative mechanism has been proposed based on theoretical analyses and experimental evidences. These results indicated that thermophilic bacteria had a well-controlled effect during the crystal growth of inorganic materials, which provided us a promising application of bacteria in biosynthesis of nanomaterials.

In this article, multi-armed nanorods and nanochains of semiconductor selenium were simultaneously synthesised through living bio-membrane bi-templates of garlic at room temperature. The multi-armed nanorods are 60–80 nm in diameter and 1.0–1.5 µm in length; the nanochains are made of a series of nanospheres and each nanosphere is 100–150 nm in its diameter. The X-ray diffraction pattern indicates that these nanocrystals were crystallised in the hexagonal structure and were of high purity. The possible formation mechanism is investigated in the article. It is expected the method reported here can be easily adapted to any future preparation of low-dimension nanomaterials.

This paper describes a bio-template method of the squama inner coat of onion for preparing the SrCrO4 nanostructures including nanospheres, nanorods and dumbbell-shaped superstructure. The method is able to make SrCrO4 nanoparticles with average diameters in the range of 90–170 nm, SrCrO4 nanorods with length in the range 0·70–2 μm, width in the range of 80–180 nm, and SrCrO4 dumbbell-shaped superstructure with length in the range 10–14 μm. The dumbbell-shaped superstructures are assembled by many SrCrO4 nanowires with length in the range 10–14 μm and width in the range 30–50 nm. The products were characterized by transmission electron microscope, powder X-ray diffraction, UV-Vis spectroscopy and luminescence spectrophotometer. A possible formation mechanism was also proposed. In the preparation, the SrCrO4 nanostructures were synthesized at room temperature without any surfactants. This new bio-template method will have potential applications in preparation of the nanoscale materials with different morphologies.

Biomimetic living bi-templates, mung bean sprouts (MBS), were employed to control the crystallization of calcium oxalate dehydrate (COD). Two kinds of crystals in different shapes were simultaneously grown on the outer surface and the inner stem wall of MBS respectively. The whole process is in the living system that material flow and energy exchange ceaselessly. The products were respectively characterized by SEM, XRD. A presumable mechanism is proposed. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

Single crystal calcium sulfate nanotubes are controllably prepared via a facile reverse micelles method at room temperature. These nanotubes have diameters of about 20 nm and lengths of about 420 nm. XRD curves indicate that as-obtained nanotubes is end-centered monoclinic phase with lattice parameters of a = 6.284 A, b = 15.193 A and c = 5.680 A, which is consistent with the values reported in JCPDS card no. 33-0311. Study on the optical properties of as obtained nanotubes shows that calcium sulfate nanotubes possess different optical properties from bulk counterpart. When reaction condition is controlled, nanorods with better crystallinity are obtained. A mechanism of the formation process is also discussed.

A biomimetic supported liquid membrane (SLM) system was employed to control the morphology of manganese carbonate. Some interesting morphologies including nanowire/hollow spheres/twinborn spheres could be readily generated by using EDA (ethylenediamine), EDTA (ethylenediaminetetracid) or NTA (nitrilotriacetic acid) as cooperative modifiers in the mineralization process, under the conditions of pH 10, 0.01% of crystal modifier and ambient temperature. The key factor in this system was the cooperative template effect of SLM and the crystal modifiers. The clarification of fantastic morphogenesis of them could be valuable for understanding of biomineralization processes. A biomimetic supported liquid membrane (SLM) system was employed to control the morphology of manganese carbonate. Some interesting results including nanowires/hollow spheres/twinborn spheres/etc. could be readily generated by using EDA (ethylenediamine), EDTA (ethylenediaminetetracid) or NTA (nitrilotriacetic acid) as cooperative modifiers in the mineralization process. The clarification of fantastic morphogenesis of them could be valuable for the understanding of biomineralization processes..

Using oleic acid as stabilizer, the monodisperse Co–Ni–Cu amorphous alloys nanoparticles were synthesized by the reduction of CuSO4·5H2O, NiCl2·6H2O and CoCl2·6H2O with KBH4 in positive microemulsion (hexane/sodium oleate/water) system. All results show that the as-synthesized spherical particles are air-stable amorphous alloy nanoparticles in room temperature with the size of 4–7 nm in narrow deviation, and are coated by oleic acid. These amorphous alloy nanoparticles have unique soft magnetic property with small coercivity (Hc) of 7.94 Oe for CuNi, 37.65 Oe for CoCu, 42.17 Oe for CoNiCu and 65.09 Oe for CoNi, respectively. After annealed at 923 K for 0.5 h, the Hc of CuNi, CoCu, CoNiCu and CoNi increased significantly to 46.7, 370.04, 337.4 and 305.5 Oe, respectively. It corresponds to the crystallization of amorphous alloy nanoparticles.

Using dibenzo-24-crown-8-ether (DB24C8) as phase transfer catalyst, the monodispersed iron–platinum (FePt) alloy nanoparticles with size of ∼17 nm were synthesized by reduction of H 2 PtCl 6 ·6H 2 O and FeCl 2 ·4H 2 O in the solvothermal system. The structure, magnetic property and electrocatalytic activity of FePt nanoparticles were characterized by transmission electron microscopy (TEM), X-ray diffraction system (XRD), vibration sample magnetometer (VSM) and CHI 820 electrochemical analyser (three electrodes system, the reference electrode is saturated calomel electrode (SCE), the counter electrode is platinum electrode and the glassy carbon electrode is used as working electrode (GCE)), respectively. The results show that the as-synthesized FePt nanoparticles have a chemically disordered fcc structure and can be transformed into chemically ordered fct structure after annealing treatment above 400 °C, simultaneously accompanying with the coercivity changed from 5 to 2400 Oe. CVs of 0.5 M H 2 SO 4 /0.5 M CH 3 OH on GCE modified with FePt nanoparticles monolayer illustrate that the as-synthesized FePt nanoparticles have strong electrocatalytic activity toward the oxidation of CH 3 OH in aqueous solution.

Pure monoclinic (m-) and tetragonal (t-) LaVO4 nanorods are successfully obtained via a facile oxides-hydrothermal method, in which V2O5 and La2O3 bulk powders are directly utilized as precursors without pretreatment. It is found that ethylenediamine tetraacetic disodium salt (EDTA) is a key factor for synthesizing t-LaVO4. The as-obtained products are characterized by X-ray powder diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), transmission electron microscopy (TEM), high-resolution TEM (HRTEM), and selected area electron diffraction (SAED). The FTIR spectra of VO4 around 800 cm−1 are suggested as an effective auxiliary means to identify the crystal phase of LaVO4. UV–Visible spectra of LaVO4 nanomaterials are obvious blue shift compared with the bulk m-LaVO4 materials. The different photoluminescent properties of Eu3+ doped m- and t-LaVO4 are demonstrated. A dissolution–precipitation mechanism is mainly responsible for the anisotropic morphology and phase control evolution of the LaVO4 nanocrystals. The oxides-hydrothermal system is also applicable to prepare other pure LnVO4 (Ln3+: Nd3+, Y3+, Sm3+) and doped LnVO4 nanomaterials.

A traditional facile method was used for the stepwise-assembly synthesis of CaSO4·2H2O nanoparticles, -tubes, -rods, and -wires. Sizes of these nanostructures vary from tens of nanometers to tens of microns. The key point of the stepwise-assembly process is the reaction time. The growth process was studied as a function of the reaction time and this was used to guide the synthesis of other one-dimensional nanomaterials in reverse micelle systems. The results showed that this growth process is somewhat universal in synthesizing inorganic salts with zero/one-dimensional and solid/hollow structures in reverse micelle systems. The growing mechanism was also explored and it was believed to be an assembly-based growth in association and concurrent with the surfactant-templating mechanism. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)

SrWO4 crystals with various morphologies have been synthesized via a system of supported liquid membrane in the presence of different additive reagents at room temperature. The X-ray diffraction patterns show that the obtained SrWO4 crystals belong to tetragonal structure. Scanning electron microscopy results reveal that additive reagents can highly affect the morphology and size of SrWO4 crystals. In fluorescence spectra there is a blue-shift emission peak at room temperature, which shows that it has potential applications in device designs and photoelectron fields. A possible growth mechanism is discussed.

Brush-like CdS arrays composed of well-arranged nanorods have been successfully synthesized for the first time through a novel chemical reaction under the low-temperature hydrothermal condition. The reaction can be described as the solvent-oxidation-hydrolysis reaction among Cd, H2O and thiourea. The products were characterized by X-ray powder diffraction (XRD), transmission electron microscopy (TEM) and photoluminescence (PL). TEM results showed that these nanorods were about 20 nm wide with lengths varying from 1.25 µm to 3.5 µm. XRD pattern indicated that as-obtained CdS was hexagonal phase with good crystallinity. PL spectrum showed the products had novel optical property from the bulk counterpart. The formation mechanism was also explored.

In this paper, the cloud point extraction and separation of scandium and yttrium (III) via use of Triton X‐114 with and without 8‐hydroquiloline (HQ) as an added chelate agent are investigated. The effects of various parameters, such as the aqueous phase pH, HQ concentration, Triton X‐114 concentration, heating temperature, and incubation time, on the cloud point extraction of scandium and yttrium (III) are studied. The results demonstrate that, there are different extraction and separation behaviors for scandium and yttrium (III) with and without HQ as an added chelate. And in contrast to solvent extraction, cloud point extraction is an excellent method to extract and separate scandium and yttrium (III).

CdS hollow/solid nanospheres and their chain-structures were successfully synthesized through supporting liquid membrane (SLM) system with bio-membrane. X-ray powder diffraction (XRD), transmission electron microscopy (TEM), UV–Vis spectroscopy, and photoluminescence (PL) spectroscopy have been used for the characterization of the products. The average diameters of CdS solid/hollow spheres are about 10, 40 nm, respectively. The wall of the hollow spheres is about 5 nm. CdS products are all cubic face-centered structure with the cell constant a = 5.830 A. We also explore the morphology, structure and possible synthesis mechanism. A possible template mechanism has been proposed for the production of the hollow CdS nanocrystals, that is, CdS nanoparticles grow along the non-soakage interface between CHCl3 and reactant solution. During this process, the organic functional groups were crucial to the control of crystal morphologies.

A neotype NdBO 3 crystal structure and its layer-by-layer nanopancakes are first obtained by mixing Nd 2 O 3 and B 2 O 3 in stoichiometric amounts without any additive via a mild oxides-hydrothermal (O-HT) process. Characterizations of the samples are carried out using X-ray powder diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and high-resolution TEM (HRTEM), and electron diffraction (ED). The pseudovaterite hexagonal structure is tentatively identified by XRD and FTIR. Typical nanopancakes are uniform nanosheets with a layer-by-layer self-assembled single-crystal structure. The thickness of each layer is about 50 nm, and the diameter is up to 14 μm. The influences of treatment time, synthesis temperature, filling ratio, and pH value of solution on products are investigated. The results show that the formation processes of NdBO 3 in the O-HT system can be assigned to two stages: M 2 O 3 (M = Nd, B) oxides transformed into hydroxide, M(OH) 3 , and the products formed by the interaction between hydroxides. Both heat-treatment time and temperature are favorable for crystal growth, but pancake-like nanostructures are destroyed beyond the appropriate conditions. Hexagonal phase NdBΟ 3 crystals can only be obtained in a narrow pH region (5 < pH < 7). The formation mechanism of pseudovaterite NdBΟ 3 is discussed. The thermal stability and irreversible phase transition properties of pseudovaterite NdBΟ 3 crystal are studied and confirmed.

The tetragonal YVO4 nanocrystals are facilely prepared via a hydrothermal solid-phase synthesis method directly utilizing bulk phase materials of V2O5 and Y2O3 as precursor. Whether additives (acid and EDTA) exist or not, the reaction can be performed in the mild temperature range from 130 to 200 °C. The products are characterized with XRD, FTIR, TEM and PL. The effect of acid and amounts of EDTA on the morphology of the product is investigated. The YVO4 nanoparticles exhibit novel photoluminescence emission bands at 330 and 606 nm under 254 nm excitation. A growth mechanism of yttrium orthovanadate is proposed.

Strontium tungstate nanorods with uniform morphology were controllably synthesized for the first time via a facile liquid–solid–solution (LSS) process through oil/water interface. These nanorods have diameters of about 50 nm and length of about 500 nm. XRD curves indicated that as-obtained nanorods were body-centered tetragonal phases with lattice parameters of a = 5.416 Å and c = 11.95 Å, which is consistent with the values reported in JCPDS card No. 08-0490. Study on the optical properties of as-obtained nanorods showed that SrWO 4 nanorods possess different optical properties from bulk counterpart. A mechanism of the formation process was also discussed.

This paper describes a facile sy]nthetic method for preparing monodisperse silver nanoparticles by bio-template of the squama inner coat of onion. The method is able to make silver nanoparticles with average diameters in the range of 4.6–7.9 nm with narrow size distribution. The important factors in the synthesis of monodisperse silver nanoparticles were discussed. The nanoparticles were characterized by transmission electron microscope, Powder X-ray diffraction and UV-Vis spectroscopy. A possible formation mechanism was also proposed. Because of its simple apparatus, high yield, convenient operation and mild conditions, this synthetic method will have potential application in preparing nanoparticles.

Ferrocene nanocrystals are successfully prepared by the ultrasonic-solvent-substitution method. Transmission electron microscopy images show that the average diameter of the nanocrystals is about (40+/-5) nm and X-ray diffraction analysis indicated that the products obtained have a high purity. The optical properties of the products are studied by IR and UV/Vis spectroscopy. UV/Vis spectra indicate that, compared with ferrocene bulk material, the nanospheres show an obvious blue shift. Cyclic voltammetry is used to test the electrocatalytic oxidation properties of the ferrocene nanospheres towards ascorbic acid on the glassy carbon electrode. The results show that the ferrocene-nanosphere-modified glassy carbon electrode exhibits a better electrocatalytic effect than that modified by the ferrocene bulk material in phosphate buffer (pH 5.00). The important factors in the preparation of and a possible mechanism for the formation of ferrocene nanospheres is also discussed. The method could potentially be applied to the preparation of nanomaterials of other organometallic compounds.

ZnWO4–TiO2 composite nanofilms on a glass slide were prepared by means of the dip-coating method, in which collodion was used as a dispersant and film-forming agent. The nanofilms are characterized through SEM, XRD, TG/DTA, PL and IR, respectively. SEM and XRD characterization of these films indicated that ZnWO4 and TiO2 particles crystallized in a monoclinic wolframite-type structure and Anatase phase, respectively, and both of these were well dispersed in the nanofilms. Compared with nanoparticles, when TiO2 nanoparticles were added in 3.61% ratio, the PL intensities of ZnWO4 nanofilms were obviously enhanced. FTIR spectra further confirmed the presence of ZnWO4 on the nanofilms.

For the first time, a novel route for preparing AWO4 (A=Zn, Cd) nanofilm on a glass substrate is proposed through the combination of reverse micelle system with dip-coating technology. Here collodion is used as a dispersant and film-forming agent to obtain nanofilm with a good quality and property. SEM and XRD results indicate ZnWO4 and CdWO4 nanoparticles with monoclinic system and wolframite structure are well dispersed on the substrate. The nanofilm’s photoluminescent(PL) bands obviously blue shift compared with bulk materials whereas red shift compared with nanoparticles, which should be due to quantum size effect and film-forming effect. FTIR absorption bands between 400 and 900 cm−1 prove the presence of ZnWO4 or CdWO4 nanoparticles on the substrate.

Rod-shape, branch-shape, bouquet-shape and claw-shape SrCrO4 crystals were synthesized through biomembrane/organic-addition supramolecular templates. The shapes are mainly changed with variance of the organic reagents and organic membranes. Most of the morphologies haven't been reported in the literature. This method may meet with the requirements to synthesize materials of various morphologies and size by using different supramolecular templates. This paper discusses how to control crystals' growth by supramolecular templates. (© 2007 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

A newly luminescent nanomaterial, monoclinic wolframite-type HgWO 4 nanoshuttles (length: 200–300 nm; diameter: 100–150 nm) is prepared through ultrasonic method. For HgWO 4 nanoshuttles, the fluorescent (FL) emitting peaks at 430 and 330 nm obviously blue shift compared with those of corresponding bulk crystals. Meanwhile, the latter almost disappear after ultrasonic irradiation procedure. A UV-visible blue-shifted (about 130 nm) absorption peak is observed at 280 nm and a new absorption peak is observed at 203 nm. FTIR results show all absorption peaks below 800 cm-1 shift to a longer wavenumber region, whereas those above 800 cm-1 remain invariable. All those unique optical performances might result from both quantum size effects and the involvement of the incompact d10 electrons. Moreover, the possible synthesis mechanism of HgWO 4 nanoshuttles is also investigated.

ZnS nanotubes with crossed-channels have been synthesized successfully using a hydrothermal method. A novel hydrothermal reaction of simultaneous solvent-oxidation-hydrolysis has been developed using Zn powder, H2O and NH2CSNH2 as reagents. TEM images show that each branch of the channels is about 400-500 nm long. The inner diameter is 55 nm, the outer diameter is 70 nm, and the interlayer spacing is about 7 nm. XRD data show that the product is well-crystallized in the cubic Sphalerite phase. The peak appears at 293 nm in the UV-Vis absorption spectrum, which is about 50 nm blue shifted from the bulk counterpart. The photoluminescence spectrum of ZnS nanotubes shows that the emission peak occurs at 409 nm when excited at 365 nm.

Partial and full AgCl nanoparticles (NPs) covered Cu@AgCl nanocables were fabricated based on Cu nanowires (NWs) through structure-director-induced assembly process in this work. The full covered Cu@AgCl nanocables, with the average diameter of ∼50nm, consist of Cu NWs core at diameter of ∼20nm and outer AgCl NPs shells with thickness of ∼15nm. Using as UV-driven photocatalysts, as-designed Cu@AgCl nanocables exhibit high performance and stability for the catalytic degradation of 4-chlorophenol pollutants. Compared with the as-prepared Cu NWs, AgCl NPs, partial AgCl NPs covered Cu@AgCl nanocables and the reference photocatalysts P25-TiO2, full AgCl NPs covered Cu@AgCl nanocables exhibit much higher photocatalytic activity (nearly 91% conversion) toward the degradation of 4-chlorophenol with the reaction rate constant (k) of 0.026min(-1). Cu NWs are found to play important roles in quickly transferring photoelectrons, facilitating more effective separation of photoinduced electrons and holes and reducing the charge recombination due to their the high conductivity.

For the first time, Cadmium tungstate (CdWO 4 )–TiO 2 composite nanofilms on a glass substrate were prepared by means of the dip-coating technique, in which collodion was used as a dispersant and film-forming agent. The films were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), thermo gravimetric and thermal analyses (TG/DTA), FTIR and photoluminescence (PL) methods, respectively. SEM and XRD characterization of these films indicated that CdWO 4 particles crystallized in a monoclinic wolframite-type structure whereas TiO 2 particles were Anatase phase; and both of them were well distributed in the nanofilms. FTIR spectra proved the presence of CdWO 4 on the nanofilms. Photoluminescent results showed that the emitting peak of CdWO 4 films blue shifted slightly relative to that of CdWO 4 crystal. Moreover, the PL intensity of CdWO 4 –TiO 2 composite nanofilm was much higher than that of CdWO 4 nanofilm. We ascribed that the introduction of TiO 2 should be responsible for the PL enhancement.

Uniform Pb(OH)Cl nanotubes were synthesized for the first time through a reverse micelles system. The system was consisting of C12E9 as a surfactant, n-pentanol as a cosurfactant, hexamethylene as the continuous oil phase and lead acetate or sodium chloride solution as the dispersed aqueous phase. The obtained Pb(OH)Cl nanotubes have an average outer diameter of 60 nm, inner diameter of about 40 nm, and an length up to 3 μm as TEM picture showed. And the range of the nanotube diameter is from 50 nm to 70 nm. XRD result indicated that Pb(OH)Cl crystallized in an orthorhombic phase. Photoluminescent (PL) spectrum showed that the product emit in near ultraviolet region and visible region at 335 nm and 439 nm respectively. The experimental results show that reaction temperature have effect on the shape of Pb(OH)Cl nanotubes. A possible formation mechanism was also discussed.

Dispersed-well FePt nanoparticles with particle size ~5 nm have been prepared by hydrazine hydrate reduction of H2PtCl6·6H2O and FeCl2·4H2O in ethanol–water system. By employing as-synthesized FePt nanoparticles, the monolayer can be formed by LB Technique. The structural, magnetic properties and electrochemical properties of FePt monolayer were respectively studied by XRD, TEM, VSM and CHI 820 electrochemical workstation. The as-synthesized particle has a chemically disordered fcc structure and can be transformed into chemically ordered fct structure after annealing treatment above 400°C. The coercivity of ordered fct FePt phase can be up to 2515Oe. CVs of 0.5 M H2SO4/0.5M CH3OH on GCE modified with FePt nanoparticles monolayer films illustrate that the as-synthesized FePt is a kind of active electrochemical catalyst.

A biomimetic supported liquid membrane (SLM) system was employed to control the morphology of strontium carbonate. Some interesting morphologies, including rods, shuttles and spheres, can be readily generated by using citric acid, nitrilotriacetic acid and ethylenediaminetetraacetic acid as cooperative modifiers in the mineralization process, under the conditions of pH 10, 0.01% of crystal modifier and ambient temperature. Seeking the cooperative balance of the SLM, the modifier agent and its concentration is the key factor in this system. In addition, this method was successfully applied to the morphology control of other alkaline earth metal carbonates, indicating its general applicability in materials preparation.

In this paper, CdSe (nanotubes, nanorods) and ZnSe (nanorods, nanoslats) were simultaneously synthesized through a biomineralization process through biomembrane bitemplates of mungbean sprouts at room temperature. The XRD patterns indicated that these nanocrystals were crystallized in the hexagonal structure and cubic structure with lattice constants a = 0.423 and c = 0.701 nm (CdSe) and a = 0.567 nm (ZnSe), respectively. The possible formation mechanism was investigated in the paper.Key words: CdSe, ZnSe, nanotubes, nanorods, nanoslats, living biomembrane, bitemplates.

Semiconductor CdS nanotubes with a small ratio of length to diameter and nanospheres were simultaneously synthesized in the light of biomineralization process through living bio-membrane bi-template of mungbean sprouts at room temperature. The outside diameter of the nanotube is 220–240 nm and the inner diameter is 200–220 nm, the length is up to 600–700 nm and the ratio of length to diameter is 2:1. The nanoshpheres are 25 nm in diameter and well distributed. The XRD pattern indicates that these nanocrystals were crystallized in the cubic structure with lattice a = 5.818 A. The optical properties of the products are illustrated, and their possible forming mechanism is explored.

AWO4 (A = Ca, Ba, Sr) nanofilms on a glass substrate are prepared through the combination of the reverse micelle system with the dip-coating technology, in which collodion is used as a dispersant and film-forming agent. The nanofilms are characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), photoluminescence (PL) and IR spectra, respectively. The results indicate that the tungstate nanoparticles having a tetragonal scheelite structure are well distributed on the substrate. PL results indicate that a blue-shift emission band peak of the nanofilms appears when they are excited at 240 nm relative to those of the bulk materials, and a red-shift emission band peak of nanofilms appears compared with nanoparticles, which can be attributed to the quantum size effect. IR spectra reveal that a large absorption band, which is ascribed to the W–O stretching vibration in WO4 tetrahedron, is observed around 820 cm−1.

Two novel dendritic superstructural and fractal BaCrO4 crystals were simultaneously synthesized in the same reaction system via facile vegetal bi-templates, mung bean sprouts (MBS). The two dendritic crystals in different shapes were grown on the outer surface and the inner stem wall of MBS. The two BaCrO4 dendrites are characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), and photoluminescence (PL). The luminescent property indicates that the products have a broad emission band peak may have applications in an electronic light device. A presumable mechanism is also given.

Hydroxyapatite nanoribbon spherulites have been successfully synthesized, with the bioactive eggshell membrane as directing template and in the presence of ethylenediamine, in a one-step reaction under mild conditions. The spherulites are about 2.5 μm in diameter and the extended nanoribbon about 1.1 μm long. The spherulites were modified with fluorescein to obtain a fluorescent probe material with strong luminescence. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)

A series of CdS nanomaterials with different morphologies and structures were self-assembled in a simple reverse micelle solvent system containing cyclohexane, aqueous solution, n-pentanol and surfactant. CdS quasi-nanospheres (i.d. 200–500 nm), CdS nanoshuttles (i.d. 248 nm and length ∼450 nm), CdS nanowires (i.d. ∼46 nm and length 1.65–4.15 μm) and CdS nanotubes (inner i.d. 25 nm, outer i.d. 38 nm and length ∼400 nm long) were produced by employing the surfactant of Tween-80, Peregals, C12E9 and Triton X-100, respectively. The CdS nanomaterials were found to possess different optical properties from the bulk CdS when analyzed by photoluminescence and UV-visible spectroscopy. A mechanism involving the possible formation of nanomaterials based on surfactant microemulsion template was also proposed.

The bactericidal action of silver (0) nanoparticles and amoxicillin on Escherichia coli is studied, respectively. Increasing concentration of both amoxicillin (0–0.525 mg ml−1) and silver nanoparticles (0–40 µg ml−1) showed a higher antibacterial effect in Luria–Bertani (LB) medium. Escherichia coli cells have different bactericidal sensitivity to them. When amoxicillin and silver nanoparticles are combined, it results in greater bactericidal efficiency on Escherichia coli cells than when they were applied separately. Dynamic tests on bacterial growth indicated that exponential and stationary phases are greatly decreased and delayed in the synergistic effect of amoxicillin and silver nanoparticles. In addition, the effect induced by a preincubation with silver nanoparticles is examined. The results show that solutions with more silver nanoparticles have better antimicrobial effects. One hypothesized mechanism is proposed to explain this phenomenon.

The paper provides a novel method of using biomembrane/organic-addition supramolecular templates to control morphologies and sizes of CaWO 4 crystals. The method can be applied for the controlled synthesis of other inorganic crystals.

In this paper, a novel method is reported by which semiconductor materials are synthesized via controlled organism membranes. Semiconductor lead selenide nanorods and nanotubes have been successfully prepared simultaneously through living bio-membrane bi-templates of the mungbean sprout. The lead selenide nanorods are approximately 45 nm in diameter, and up to 1100 nm in length; all of them are single crystalline in structure. Lead selenide nanotubes are 50 nm in diameter, and up to 2000 nm in length, and are poly-crystalline in structure. The characteristics of the products are illustrated by various means, and their possible formation mechanism is explored.

By the employment of supramolecule templates composed of biomembrane and organic reagents, control over the morphologies and sizes of BaWO 4 crystals has been successfully achieved, and a series of flower-like, sphere-like, fasciculus-like, and other morphologies of BaWO 4 were obtained at room temperature. Most of the morphologies are reported for the first time. Furthermore, the control rule of supramolecule templates was also discussed. This method may satisfy the requirements of materials of various morphologies and sizes by using different supramolecule templates, and provide significant theoretical reference to the controlled synthesis of other crystals.

This article describes a novel biomimetic strategy for the synthesis of CaCO3 crystals with different structures by a supported liquid membrane containing a mobile carrier, and first reports the abnormal structure conversion of CaCO3 from calcite to vaterite. Furthermore, we found that the sub-micron-sphere vaterite prepared by the supported liquid membrane was a nano-self-assembled system. This kind of vaterite has a bright future for various applications.