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In this study, cube-like LaB6 was synthesized by Mg coreduction of LaCl3 and B20,3. Then, boron nitride nanoboxes (BNNBs) were produced by nitriding cube-like LaB6, and the latter is not only played as boron source, but also as hard template. The results of characterization (transmission electron microscopy and scanning electron microscopy) indicate that the BN products are hollow structures, the diameter of the nanoboxes is in the range of 200-1000 nm, and the wall thickness of the BN nanoboxes is 16 nm. The specific surface area of BN nanoboxes is 45 m2/g, the pore size is mainly located at 10 nm, and the total pore volume is 0.16 cm3/g. The nitriding of cube-like LaB6 into hollow BNNBs here would provide an alternative route for the synthesis of other hollow BN architectures by other boron-containing materials.

Fe3O4@C core-shell nanorings (R-Fe3O4@C) were fabricated by a synchronous reduction and carbon deposition process. As the anodes for lithium-ion batteries, these R-Fe3O4@C exhibit a high capacity, excellent cycling stability and good rate performance. This ring-shaped core-shell nanostructure design may pave the way to enhance electrochemical performances of electrode materials.

A hydrothermal route has been developed to synthesize lead telluride (PbTe) nanostructures through the reaction between Pb(CH3COO)2 and Na2TeO3. When the surfactant poly(vinyl pyrrolidone) (PVP) was introduced into the solution, uniform PbTe nanorods with a diameter of about 30 nm could be prepared, while absent of PVP, PbTe nanotubes could be synthesized. Furthermore, some interesting Y-, V-, crisscross-shaped PbTe nanotubes were reported for the first time. The resulting materials were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM) and high-resolution TEM (HRTEM). Two different mechanisms are identified to explain the formation of the nanorods and nanotubes herein. A surfactant-assisted oriental attachment mechanism is explained to describe the formation of PbTe nanorods, whereas, we deduce PbTe nanotubes follow a self-generated template route.

Carbon nanocages (CNCs) have been synthesized through a simple approach using different alcohols and ferrous oxalate as reactants at 550 °C for 12 h in a sealed autoclave. The lengths of the sides of the CNCs are about 200-350 nm and the wall thicknesses are about 10-15 nm. The formation mechanism of the CNCs is also discussed, based on the experimental results. These CNCs show excellent removal efficiency for phenolic compounds, ammonia, and total particulate matter from cigarette smoke. The adsorption capability of CNCs prepared from ethanol is much higher than that of other samples. For example, the efficiency of 5 mg CNCs (ethanol) for removing the six phenolic compounds p-dihydroxybenzene, m-dihydroxybenzene, o-dihydroxybenzene, phenol, m-cresol, and o-cresol can reach 57.31%, 62.25%, 65.58%, 75.95%, 54.34% and 59.43%, respectively, while that of the commercial activated carbon (5 mg) can only reach 29.02%, 33.93%, 35.00%, 36.00%, 20.33% and 36.19%, respectively, under the same conditions., (This journal is © The Royal Society of Chemistry 2011)

A general and facile synthetic route has been developed to prepare 1D semiconductor nanomaterials in a binary solution of distilled water and ethanol amine. The influence of the volume ratio of mixed solvents and reaction temperature on the yield and final morphology of products was investigated. Significantly, this is the first time that wurtzite ZnSe ultrathin nanobelts have been synthesized in solution. It has been confirmed that the photocatalytic activity of ZnSe nanobelts in the photodegradation of the fuchsine acid is higher than that of TiO(2) nanoparticles. The present work shows that the solvothermal route is facile, cheap, and versatile. Thus, it is very easy to realize scaled-up production, and brings new light on the synthesis and self-assembly of functional materials.

CuO microspheres with hollow interiors were synthesized by a simple method using urea as an important reagent to generate soft-template. X-ray diffraction pattern, Infrared spectrum, electronic diffraction, field emission scanning electron microscopy images, transmission electron microscopy images and high-resolution transmission electron microscopy investigated the phase structures and morphologies of CuO microspheres. The hollow spheres may be formed through the assembling of nanoparticles with the assistance of gas bubbles and a self-generated template and aggregation process was proposed for the formation mechanism of the CuO spheres.

The gamma-AIOOH (boehmite) nanofiber bundles have been synthesized via a convenient quencher method. Most nanofibers contain even smaller nanowires with an average diameter of 5 nm. A series of contrast experiments reveal that the evolvement from nanosheets to nanofibers occurs in the quencher process. gamma-Al2O3 nanofiber bundles with mesoporous character can be obtained by calcining relevant gamma-AlOOH nanostructures at 500 degrees C.

A two-step synthesis method was developed to fabricate Mn-doped zinc aluminate (ZnAl2O4) nanoparticles, including the first step of ageing, and the second step of crystallization. The effects of preparation conditions, such as ageing temperature, crystallization time, and the pH on the Mn-doped ZnAl2O4 nanoparticles were systematically investigated. The photoluminescence (PL) properties of green phosphor Mn-doped ZnAl2O4 nanoparticles were also discussed. Compared with the bulk sample, the PL spectrum of Mn-doped ZnAl2O4 nanoparticles has distinct blue shift. This procedure provides a facile way for the synthesis of well-crystallized ZnAl2O4:Mn at low temperature.

A simple and efficient microemulsion-based technique, which used the new Tx-100/cyclohexanol/ H2O system, was developed to synthesize SrCrO4 nanowire based nanostructures, including nanowire bundles and flower-like structures at different temperature. X-ray powder diffraction (XRD), field emission scanning electron microscope (FE-SEM), transmission electron microscopy (TEM) and high-resolution TEM (HRTEM) were used to characterize the products. Studies found that the reaction temperatures and the reaction systems have great influences on the final products. Optical properties studies by UV-Vis spectra and photoluminescence (PL) spectra confirmed that the as-obtained nanowires showed distinct optical activity under UV and visible light irradiation.

The 3D beta-In2S3 flowerlike architecture assembled from nanoflakes was prepared via a novel complex-precursor assisted (CPA) solvothermal route. The as-prepared beta-In2S3 powder was characterized by X-ray diffraction pattern (XRD), X-ray photoelectron spectra (XPS), transition electron microscopy (TEM), field emission scanning electron microscopy (FE-SEM), ultraviolet-visible light (UV-vis) spectra, and photoluminescence spectrum. The novel 3D beta-In2S3 nanostructure exhibit a strong quantum confinement effect. FT-IR spectra were used to investigate the coordinative chemical effect in the complex. A possible mechanism was discussed.

SnS2 nanobelts were successfully synthesized through a controllable solution-phase hydrothermal method on a large scale. The nanobelts have a very high yield, which is more than 95%, with widths ranging from 100 to 200 nanometers, lengths up to several micrometers and thicknesses ca. 10 nanometers. X-ray diffraction patterns, electronic diffraction, X-ray photoelectron spectra, field emission scanning electron microscopy images, transmission electron microscopy images and high-resolution transmission electron microscopy investigated the phase structures, compositions, and morphologies of SnS2 nanobelts. Dodecanethiol played important roles in the process of SnS2 nanobelts formation and growth. The formation mechanism of SnS2 nanobelts was investigated and discussed on the basis of the experimental results.

Single-crystalline PbI2 nanobelt bundles have been prepared using lead monoxide powder and hydroiodic acid as reagents at the assistance of dodecylamine. The assembled PbI2 nanobelt bundles can be spilt into nanobelts through long-playing sonication. The prepared nanobelt bundles consist of several nanobelts and the nanobelts have lengths of tens of microns, widths of 50-150 nanometers, and thicknesses ca. 20 nanometers. X-Ray diffraction (XRD), scanning electron microscopy (SEM), field emission scanning electron microscopy (FE-SEM) transmission electron microscopy (TEM), electronic diffraction (ED), and high-resolution transmission microscopy (HRTEM) was used to characterize the as-prepared product. The possible formation mechanism of PbI2 nanobelt bundles was tentatively proposed.

Nanocrystalline niobium nitride (NbN0.9) was successfully synthesized at 600 degrees C through a solid-state reaction. The synthesis was carried out in an autoclave by using NbCl5 and NaN3 as the reactants. The X-ray powder diffraction pattern indicates the formation of cubic NbN0.9. Transmission electron microscopy images show that typical NbN0.9 crystallites are composed of uniform particles with an average size of about 30 nm and nanorod crystallites with a typical size of about 40 x 2500 nm. Magnetic measurements exhibited that a superconducting transition occurred at 15.4 K for the NbN0.9 product.

Titanium nitride hollow spheres were synthesized by the reaction of TiCl4 and NaNH2 at room temperature. X-ray powder diffraction (XRD) pattern could be indexed as cubic TiN with the lattice constants of a = 4.236 A. Transmission electron microscopy (TEM) images showed hollow spheres with diameter about 200 nm. A possible formation mechanism of TiN hollow spheres was discussed.

This article describes a surfactant-assisted approach to the size-controlled synthesis of uniform nanorods of trigonal tellurium (t-Te). These nanorods were grown from a colloidal dispersion of amorphous Te (a-Te) and t-Te nanoparticles at room temperature, which was first formed through the reduction of (NH4)2TeS4 by Na2SO3 in aqueous solution at 80 degrees C. Nuclei formed in the reduction process had a strong tendency to grow along the [001] direction due to the inherently anisotropic structure of t-Te. The formation of Te nanorods could be ascribed to the confined growth through the surfactant adsorbing on the surfaces of the growing Te particles. By employing various surfactants in the synthesis system, Te nanorods with well-controlled diameters and lengths could be reproducibly produced by this method. Both the diameters and lengths of nanorods decreased with the increase of the alkyl length and the polarity of the surfactants. Te nanorods could also be obtained in mixed surfactants, where the different surfactants were used to selectively control the growth rates of different crystal planes. We also observed that the as-synthesized nanorods with uniform size could be self-assembled into large-area smecticlike arrays.

Main observation and conclusion: There is no doubt that SiOx and carbon composite is one of the promising anode materials for lithium‐ion batteries owing to its high capacity and rational cycling stability. Herein, we report a sol‐gel synthesis followed by molten salt carbonization route to fabricate graphene‐like carbon nanosheet wrapped SiOx/C submicrospheres (SiOx/C@2D‐C). The in‐situ generated carbon nanosheets under molten salt condition can further improve the electroconductivity, restrain the volumetric expansion and guarantee the structural integrity of the electrode. As a result, the as‐obtained SiOx/C@2D‐C delivers a discharge capacity of 559 mAh·g−1 at 0.5 A·g−1 after 200 cycles and 548 mAh·g–1 at 1.0 A·g−1 even after 1000 cycles. The full cell assembled with SiOx/C@2D‐C as anode and commercial LiFePO4 as cathode can achieve an energy density of 200 Wh·kg−1 and maintain a capacity of 66.7% after 100 cycles with a working potential of 2.8 V. The approach is simple and cost effective, which is promising for mass production of SiOx‐based materials for high energy LIBs. [ABSTRACT FROM AUTHOR]

Although the preparation of hierarchical structures of transition-metal oxides (TMOs) has been intensively studied in recent years, it is still a great challenge to synthesize hierarchical multicomponent TMOs. Herein, we report a versatile method to fabricate three-component TMOs, namely MnO2@NiO/NiMoO4 nanowires@nanosheets hierarchical porous composite structures (HPCSs). Through a combination of a chemical-solution-based route and subsequent calcination, the as-prepared MnOOH@NiMo precursor is topotactically transformed to MnO2@NiO/NiMoO4 HPCSs without notable structural variation. Ultrathin NiO/NiMoO4 nanosheets become interconnected into a honeycomb analogue with plentiful mesopores. Comparative results demonstrate the vital role of hexamethylenetetramine (HMT), and the solvent system in the formation of the MnOOH@NiMo precursor. When examined as electrode materials for electrochemical capacitors, MnO2@NiO/NiMoO4 HPCSs, with an areal mass loading as high as 5 mg cm−2, deliver a specific capacitance of 918 F g−1 at a current density of 1.0 A g−1 and maintain good cycling stability, which displays better electrochemical performance than electrodes composed of a single component. Note that a high-voltage asymmetric supercapacitor is configured with MnO2@NiO/NiMoO4 HPCSs (still as high as 2 mg cm−2) against activated carbon, and exhibits outstanding cycling stability with a high energy density of 26.5 Wh kg−1 and a power density of 401 W kg−1. These analytical and experimental results clearly confirm the advantages of distinctive 3D multicomponent hierarchical architectures for engineering high-performance electrochemical capacitors. [ABSTRACT FROM AUTHOR]

Hollow structures of transition-metal oxides, particularly mixed-metal oxides, could be promising for various applications such as lithium-ion batteries (LIBs). Compared to the synthesis of metal oxide hollow spheres by the template method, non-spherical metal oxide hollow hexagonal polyhedra have not been developed to date. Herein, we report the controlled hydrothermal synthesis of a new phase of Co3V2O8⋅ n H2O hollow hexagonal prismatic pencils (HHPPs), which is composed of uniform structural units. By varying the amount of NaOH in the presence of NH4+ and without any template or organic surfactant, the hexagonal prismatic pencils gradually transform from solid into hollow structures, with sizes varying from 5 to 20 μm. The structure of pencils can be preserved only in a limited range of the molar ratio of OH−/NH4+. As a new anode material for LIBs, such hollow pencils exhibit impressive lithium storage properties with high capacity, good cycling stability, and superior rate capability. [ABSTRACT FROM AUTHOR]

A facile two-step strategy involving a polyol method and subsequent thermal annealing treatment is successfully developed for the large-scale preparation of ZnCo2O4 various hierarchical micro/nanostructures (twin mcrospheres and microcubes) without surfactant assistance. To the best of our knowledge, this is the first report on the synthesis of ZnCo2O4 mesoporous twin microspheres and microcubes. More significantly, based on the effect of the reaction time on the morphology evolution of the precursor, a brand-new crystal growth mechanism, multistep splitting then in situ dissolution recrystallization accompanied by morphology and phase change, is first proposed to understand the formation of the 3D twin microshperes, providing new research opportunity for investigating the formation of novel micro/nanostructures. When evaluated as anode materials for lithium-ion batteries (LIBs), ZnCo2O4 hierarchical microstructures exhibit superior capacity retention, excellent cycling stability at the 5 A g−1 rate for 2000 cycles. Surprisingly, the ZnCo2O4 twin microspheres show an exceptionally high rate capability up to the 10 A g−1 rate. It should be noted that such super-high rate performance and cycling stability at such high charge/discharge rates are significantly higher than most work previously reported on ZnCo2O4 micro/nanostructures and ZnCo2O4-based heterostructures. The ZnCo2O4 3D hierarchical micro/nanostructures demonstrate the great potential as negative electrode materials for high-performance LIBs. [ABSTRACT FROM AUTHOR]

A new thread for improving the cycling stability of Fe2O3 nanorice is proposed through combining the electrochemical porousness (EP) effect and solid-electrolyte interphase (SEI) thermolysis approach. Starting from solid Fe2O3 nanorice, this process could be applied to prepare porous Fe2O3 nanorice with a good coating of a porous SEI thermolysis layer composed of carbon and Li2O. The interconnecting pores and full coating of the SEI thermolysis layer provides not only mechanical resistance of the Fe2O3 nanorice against pulverization, but also high electrical and ionic conductivity over the electrode throughout long cell cycles. This method results in the enhancement of cycling ability and capacity, which is demonstrated by comparison with the starting Fe2O3 nanorice. After the EP and SEI thermolysis approach, the Fe2O3 nanorice exhibits an energy capacity retention about of 680 mAhg-1 at a current density of 1000 mAg-1 over 250 cycles, which is more than 82% of the initial reversible capacity. Moreover, it also has an excellent rate capability and high coulombic efficiency. This strategy provides a simple and convenient route toward stable charge/discharge cycling for not only Fe2O3, but also for other electrode materials that are subject to large volume changes and low charge voltages. At the same time, it also contributes to a fundamental understanding of improved cycling stability and reversible capacity for electrode materials. [ABSTRACT FROM AUTHOR]

In this work, various novel NiO hierarchical nanostructures, including mesoporous nanotubes by nanoparticles self-assembly, nanowire bundles, dandelions, hollow spheres by rods self–assembly, have been fabricated by a simple hydrothermal process and subsequent thermal decomposition at atmosphere. A detailed study of the effect of experimental parameters on the morphology is also presented. Results and analyses demonstrated that oxalic-acid/NaOH molar ratio has an immense function in the subtle morphology control of NiO products. Electrochemical characterization demonstrated that the mesoporous NiO nanotubes were capable of delivering a specific capacitance (SC) of 405 F g−1at the current density of 0.5 A g−1and offered good capacitance retention of ca.91% after 1500 continuous charge-discharge cycles. This soundly indicates that as electrode material, the as-prepared NiO mesoporous nanostructures could meet key requirements in terms of large power density, outstanding rate capability and excellent electrochemical stability. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, hollow spherical Cu3P nanopowders were synthesized by using copper sulfate pentahydrate (CuSO4⋅5H2O) and yellow phosphorus in a mixed solvent of glycol, ethanol and water at 140–180 ∘C for 12 h. X-ray powder diffraction (XRD), energy dispersive X-ray spectroscopy (EDX), electron diffraction pattern (ED) and transmission electronic microscopy (TEM) studies show that the as-synthesized nanocrystal is pure hexagonal phase Cu3P with a hollow spherical morphology. Based on the TEM observations, a possible aggregation growth mechanism was proposed for the formation of Cu3P hollow structures. Meanwhile, the effects of some key factors such as solvents, reaction temperature and reaction time on the final formation of the Cu3P hollow structure were also discussed. [Copyright &y& Elsevier]

Abstract: Microspheres assembled from carbon nanotubes (MCNTs), with the diameters ranging from 5.5 to 7.5μm, were synthesized by means of pyrolysis of polypropylene and maleated polypropylene in an autoclave. The characterization of structure and morphology was carried out by X-ray diffractometer (XRD), field-emission scanning electron microscopy (FESEM), (high resolution) transmission electron microscope [(HR)TEM)], selected-area electron diffraction (SAED) and Raman spectrum. As a typical morphology, the possible growth process of MCNTs was also investigated and discussed. The results of nitrogen adsorption–desorption indicate that the Brunauer–Emett–Teller (BET) surface area (140.6m2/g) of the MCNTs obtained at 600°C is about twice as that (74.5m2/g) of carbon nanotubes obtained at 700°C. The results of catalytic experiment show that MCNTs based catalyst has higher catalytic activity than the carbon nanotubes based catalyst for the preparation of methanol and dimethoxy-ethane by oxidation of dimethyl ether. [Copyright &y& Elsevier]

Abstract: Bundle-like nanostructures have been synthesized via a hydrothermal treatment with the assistance of cetyltrimethylammonium bromide (CTAB). The as-synthesized bundle-like nanostructures are composed of well-aligned tellurium (Te) nanorods with lengths of 500nm and diameters ranging from 30 to 50nm. The formation mechanism of the Te nanostructures has been investigated and discussed. The concentration of CTAB and hydrothermal treatment temperature played crucial roles, and could be used as the parameters to control morphology of the bundle-like nanostructures. Moreover, the photoluminescence properties of the bundle-like Te nanostructures have also been studied. [Copyright &y& Elsevier]

Main observation and conclusion: There is no doubt that SiOx and carbon composite is one of the promising anode materials for lithium‐ion batteries owing to its high capacity and rational cycling stability. Herein, we report a sol‐gel synthesis followed by molten salt carbonization route to fabricate graphene‐like carbon nanosheet wrapped SiOx/C submicrospheres (SiOx/C@2D‐C). The in‐situ generated carbon nanosheets under molten salt condition can further improve the electroconductivity, restrain the volumetric expansion and guarantee the structural integrity of the electrode. As a result, the as‐obtained SiOx/C@2D‐C delivers a discharge capacity of 559 mAh·g−1 at 0.5 A·g−1 after 200 cycles and 548 mAh·g–1 at 1.0 A·g−1 even after 1000 cycles. The full cell assembled with SiOx/C@2D‐C as anode and commercial LiFePO4 as cathode can achieve an energy density of 200 Wh·kg−1 and maintain a capacity of 66.7% after 100 cycles with a working potential of 2.8 V. The approach is simple and cost effective, which is promising for mass production of SiOx‐based materials for high energy LIBs. [ABSTRACT FROM AUTHOR]

Abstract: Nanocrystalline niobium nitride was synthesized via benzene-thermal reaction of NbCl5 and NaN3 in an autoclave at 380°C. X-ray powder diffraction pattern indicated that the product was cubic NbN, and the cell constant was a = 4.419Å. Transmission electron microscopy image showed that the sample consisted of particles with the diameters of 10–20nm. Benzene solvent played an important role in the formation of nanocrystalline NbN. [Copyright &y& Elsevier]

Abstract Prussian blue (PB) and its analogues (PBAs) have been regarded as one of promising electrode candidates in aqueous batteries, due to its open framework, robust skeleton, and simple preparation protocol. However, intrinsic structure vacancies and poor electron conductivity lower their electrochemical performances, particularly in terms of reversible capacity, rate capability, and cycling stability. Here, truncated cobalt hexacyano-ferrate nanocubes threaded by carbon nanotubes are synthesized with the assistances of citrate and glycerol. The low content of structure vacancies in cobalt hexacyanoferrate, and the intimate contact between it and carbon nanotubes, well address the above issues, resulting in excellent performances in rechargeable aqueous batteries. The reversible capacity reaches 107.2 mAh g−1 at 0.1 A g−1, 87.3% of which is kept at 5 A g−1. After paired with Zn foil as a dual-ion full cell, it delivers a high energy of 107.1 Wh kg−1 cathode at 7.87 kW kg−1 cathode , exhibiting the high energy and high power simultaneously. All these results indicate the promising potential of this composite in rechargeable aqueous batteries. Highlights • Truncated cobalt hexacyanoferrate nanocubes are threaded by carbon nanotubes. • This composite shows reduced structure vacancies and enhanced conductivity. • The specific capacity reaches 107.2 mAh g−1 at 0.1 A g−1 and 95 mAh g−1 at 5 A g−1. • This composite is paired with Zn for dual-ion aqueous batteries. • Full cells deliver an energy density of 107.1 Wh kg−1 at 7.87 kW kg−1. Graphical abstract Image 1 [ABSTRACT FROM AUTHOR]

Highlights: [•] LiNi0.5Mn1.5O4 nanostructures are prepared from urchin-like γ-MnO2. [•] Subsequent annealing brings about different phase and cationic composition. [•] Two-phase intergrowth is observed in the sample without annealing treatment. [•] The special structural characteristics endow the sample enhanced performance. [Copyright &y& Elsevier]

Abstract: MnCO3 microstructures, including 2.3μm microplates with the thickness of 200nm and 3.1μm microspheres stacked with 50nm-thick sheets, were hydrothermally prepared in the assistance of sodium dodecyl benzene sulphonate (SDBS) and dodecyl sulfonic acid sodium (SDS), respectively. With the as-synthesized MnCO3 as precursors followed by annealing at 400°C for 4h, mesoporous γ-MnO2 microplates and microspheres with the pore size of 4–50nm, which basically preserved the initial shapes, were obtained. The Brunauer–Emmett–Teller surface areas of the as-prepared γ-MnO2 microplates and microspheres were 52.1m2 g−1 and 50.2m2 g−1, respectively. The electrochemical property tests over Li+ batteries showed that the initial discharge capacity of γ-MnO2 microplates and microspheres were 1997mAhg−1 and 1533mAhg−1. Noticeably, even after 100cycles, the discharge capacity of γ-MnO2 microplates was still as high as 626mAhg−1, indicating the decent cycle behavior. In addition, mesoporous γ-MnO2 was also applied as adsorbents in water treatment, and γ-MnO2 microplates and microspheres could remove about 55% and 80% of Congo red. [Copyright &y& Elsevier]

Abstract: Three types of Eu3+-doped LaPO4 three-dimensional (3D) microstructures have been hydrothermally prepared by adjusting pH value and the molar ratio of La3+ and Eu3+ to phosphorus of Na5P3O10 (Ln/P) at 180°C. As the pH value was 0.15 and the molar ratio of Ln/P was in the range of 1/1 to 1/4, 5μm urchinlike spheres composed of long nanorods of hexagonal LaPO4:Eu were obtained. As the pH value was 1.00 and the molar ratio of Ln/P was 1/1, 3μm hollow spheres consisting of short nanorods of monoclinic LaPO4:Eu were prepared. Keeping the pH value at 1.0 and the molar ratio of Ln/P at 1/4, 6μm core–shell spheres of monoclinic LaPO4:Eu formed. Luminescent measurements were performed. Hollow spheres of monoclinic LaPO4:Eu had the strongest emission intensity. However, the emission intensity of monoclinic core/shell structure was even lower than that of hexagonal LaPO4:Eu urchinlike spheres. [ABSTRACT FROM AUTHOR]

Abstract: Fe3O4 hollow microsphere chains with lengths of 8–11 μm have been solvothermally synthesized in the mixed solution of glycerol and water with 1 M NaOH. The hollow microspheres have diameters in the range 0.7–1 μm, and the thickness of the shells is 150–300 nm. The shell of the hollow microspheres is constructed by octahedrons of 100–170 nm. However, when the concentration of NaOH is adjusted to 3 M, the octahedron chains with lengths of 30–50 μm can be obtained. The magnetic saturation values of hollow microsphere chains and octahedron chains are 88.1 and 102.4 emu/g at room temperature, respectively. [Copyright &y& Elsevier]

Abstract: The concentration of the Mn(NO3)2 solution has significant influence on the morphologies and the phases of the MnO2 products. A large number of - MnO2 nanowires were prepared via a simple pyrolysis under lower reaction concentration. The nanowires have lengths up to tens of micrometers and diameters in the range of 20–100 nm. The - MnO2 nanobundles and nanoflowers were prepared by increasing the concentration of Mn(NO3)2 solution. The superparamagnetism of - MnO2 nanowires and paramagnetism of - MnO2 nanoflowers indicate their potential applications in magnetic materials. [Copyright &y& Elsevier]

Abstract: Polycrystalline InP hollow nanospheres with an average size of 520nm and shell thickness of about 110nm were obtained by acid treatment of In/InP core–shell nanospheres which were solvothermally synthesized in ethanolamine–water binary solution at 180°C. The sizes of InP hollow nanospheres increased with the increasing reactants quantities. Meanwhile the shell thicknesses of InP hollow nanospheres could be controlled by varying the quantity of yellow phosphorus. The process of In/InP core–shell nanospheres transforming into InP hollow nanospheres was also investigated. The InP products prepared in our experiments can emit blue light, which is different from previous reports and increases the potential application of InP nanomaterial. [Copyright &y& Elsevier]

Abstract: Uniform bismuth selenide hollow nanospheres were synthesized on a large scale in a mixed solvent of ethylene glycol (EG) and oleic acid (OA). The diameter of the Bi2Se3 hollow nanospheres is about 600 nm and the thickness of the shell is about 40 nm. The shape evolution of Bi2Se3 nanostructures with different volume ratios of EG and OA was also observed: nanoflakes in EG solution, hollow nanospheres as of 2/3, and finally flower-like nanostructures in OA solution. [Copyright &y& Elsevier]

Abstract: ZnO nanowires (∼60%) and nanobelts (∼40%) have been fabricated on a large scale via a low temperature one-pot hydrothermal technique. Na2CO3 was introduced not only as alkaline source but also as a controllable reagent for the crystal growth of ZnO. The comparison experiment results indicate that the adding amount of Na2CO3 greatly affect the length/diameter aspect ratios of 1D ZnO nanocrystals. In addition, the introduction of surfactant SDSN was indispensable in controlling the growth of belt-like ZnO. Room temperature photoluminescence spectrum showed a weak UV band emission at 379nm and a strong broad yellow emission around 564nm. A possible mechanism on the formation of the ZnO nanowires was proposed. [Copyright &y& Elsevier]

Abstract: ZnS hollow nanospheres have been hydrothermally synthesized at 200°C for 4h. In same condition ZnS microspheres were obtained when using acrylamide as the surfactant. XRD pattern indicates as-prepared sample is cubic ZnS with cell constant a =5.391Å and the average size of ZnS particles was 6.5nm estimating from the Debye–Scherrer formula. TEM observed the hollow nanospheres have the diameters ranging from 200 to 300nm with a shell thickness of about 40nm. UV–vis and PL spectra recorded the optical properties of the sample, a blue-shift (∼19nm) was observed. It appears that the hollow spheres might be formed by soft-template of gas bubbles of SO2 produced during the reaction. [Copyright &y& Elsevier]

Abstract: The cubic β-In2S3 hollow nanospheres was fabricated via two-step solvothermal approaches using InCl3·4H2O, CS2, and thioacetamide (C2H5NS) as the starting materials. The as-prepared cubic β-In2S3 possessed hollow nanosphere structures, whose outward diameters and shells are −75 and 20nm, respectively. The samples were characterized by XRD, FESEM, TEM, SAED, and HRTEM. The optical properties of the cubic β-In2S3 hollow nanospheres were also investigated. UV–vis (280nm) and PL (367nm) spectra indicate that there exists obvious blue shift compared with the In2S3 bulk materials. [Copyright &y& Elsevier]

Abstract: Mn-doped Zn2SiO4 phosphors with different morphology and crystal structure, which show different luminescence and photoluminescence intensity, were synthesized via a low-temperature hydrothermal route without further calcining treatment. As-synthesized zinc silicate nanostructures show green or yellow luminescence depending on their different crystal structure obtained under different preparation conditions. The yellow peak occurring at 575nm comes from the β-phase zinc silicate, while the green peak centering at 525nm results from the usual α-phase zinc silicate. From photoluminescence spectra, it is found that Zn2SiO4 nanorods have higher photoluminescence intensity than Zn2SiO4 nanoparticles. It can be ascribed to reduced surface-damaged region and high crystallinity of nanorods. [Copyright &y& Elsevier]

Abstract: High-density aligned ZnO nanorods films were grown on zinc-covered Si wafer by using hydrothermal method in the alkali solution containing hydrogen peroxide (H2O2). The growth process involves the oxidation of zinc into oxidized zinc species cluster in the alkali solution containing hydrogen peroxide (H2O2) and the ZnO nanorods growth process in which oxidized zinc species provide seeds for nucleation site of nanorods ZnO crystal growth during hydrothermal process. The hydrogen peroxide plays a key role in formation of oxidized zinc species cluster. Room temperature PL spectrum and Raman spectrum of the sample are also studied and indicate that there is a very low concentration of oxygen vacancies in the highly oriented ordered ZnO nanorods. [Copyright &y& Elsevier]

Abstract: CuO nanotube arrays and nanoflower films have been prepared in large area, respectively. Ordered CuO nanotube arrays were successfully prepared by heating the corresponding Cu(OH)2 nanotube precursors in N2, while CuO nanotube arrays with special nanoplate wall structure were obtained by heating the Cu(OH)2 nanotube precursor in benzene solvent in autoclave solvothermally. Besides, CuO nanoflower film was directly prepared via the oxidation reaction of copper foil in autoclave hydrothermally. The samples have been characterized by X-ray diffraction, scanning electron microscopy and high-resolution transmission electron microscopy. These novel hierarchical CuO nanoarchitectures may be used as nanobuilding blocks for field emitters and other nanoelectronic devices. [Copyright &y& Elsevier]

Abstract: Zn-doped Ni nanotubes with wall thickness in the range of 10–20 and 100–200nm in inner diameter have been synthesized in ethanol via a room-temperature solution synthetic route. Powder X-ray diffraction (XRD) pattern shows that the as-synthesized particles have a chemically disordered fcc structure. The coercivity of the products was investigated to be 515.6Oe at room temperature. The catalytic property of Zn-doped Ni nanotubes was also conducted. [Copyright &y& Elsevier]

Abstract: Arrays of NiO nanoparticles have been synthesized via thermal decomposition of nickel dimethylglyoximate precursor. The structure, morphology and properties of the products were characterized by XRD, TEM, SAED and UV–vis spectrophotometry. TEM reveals that one-dimensional arrays consist of NiO nanoparticles. XRD and SAED indicate that these NiO nanoparticles crystallize with a polycrystalline structure. The optical absorption band gap of NiO nanoparticles is 3.51eV. [Copyright &y& Elsevier]

Abstract: The composite oxide CuO/Mn3O4 and its mesoporous composite were prepared through co-precipitation method. The preparation conditions of CuO/Mn3O4 were tested and ascertained as following: Mn:Cu, 2:1; NaOH solution, 25% (w/w); volume, 6mL; without aging; drying temperature, 90°C; calcination temperature, 200°C; calcination time, 3h. CuO/Mn3O4, the mesoporous solid, and the mesoporous composite were characterized by X-ray power diffraction (XRD), high-resolution transmission electron microscope (HRTEM). The HRTEM image showed that CuO/Mn3O4 had been loaded into the pores of the mesoporous solid and the average diameter of CuO/Mn3O4 particles was about 4nm. The specific surface area and the aperture distribution of the mesoporous solid and the mesoporous composite were measured by N2 adsorption. The catalytic activity and stability of CuO/Mn3O4 and the mesoporous composite were evaluated on a small fixed reaction bed and an online GC. The tar and some other harmful components in cigarette smoke can be reduced by using dual-filters containing the mesoporous composite. Comparing with the reference cigarette smoke, the tar, CO, benzo[α] pyrene and tobacco-specific N-nitrosoamines (TSNAs) in the tested cigarette smoke were reduced by 27.2, 23.8, 30.1, and 38.1%, respectively. [Copyright &y& Elsevier]

Abstract: One-dimensional (1D) nanostructured materials, chromium nitride (CrN) nanorods have been prepared initially via a direct thermal solid-state reaction of anhydrous chromium(III) tetrachloride (CrCl3) and sodium azide (NaN3) at a temperature of 600°C for 12h. The X-ray diffraction pattern of the product is indexed as cubic CrN. Transmission electron microscope images indicate that the sample consists of CrN nanorods with the diameters of 40–60nm and lengths in the range of 500nm to 1μm. X-ray photoelectron spectroscopy (XPS) results show the mole ratio of Cr:N as 1.15:1. The possible reaction mechanism is also discussed. [Copyright &y& Elsevier]

Abstract: Large-scale copper sulfide polycrystalline nanorods have been solvothermally synthesized through a Cu(acac)2 precursor decomposition and reaction route. X-ray diffraction (XRD) showed that the product was hexagonal phase CuS with lattice constants of a =3.795Å and c =16.42Å. Field emission scanning electron microscopy (FESEM) and transmission electron microscopy (TEM) investigated the morphology of the product under the different growth conditions. PL spectra indicated that the rod-shaped product had emission peaks at 414 and 437.5nm when the excitation wavelength was 371.5nm, but the CuS dendrite did not demonstrate emission peaks at the same condition. A mechanism of Cu(acac)2 micronrods decomposition and reaction with CS2 in situ was suggested based on the TEM observation. [Copyright &y& Elsevier]