Microwave-assisted synthesis of sulfide M2S3 (m = Bi, Sb) nanorods using an ionic liquid

Single-crystalline Bi(2)S(3) and Sb(2)S(3) nanorods have been successfully synthesized by the microwave-assisted ionic liquid method. The starting reagents were Bi(2)O(3) or Sb(2)O(3), HCl, Na(2)S(2)O(3), and ethylene glycol (EG) or ethanolamine, and the ionic liquid used was 1-butyl-3-methylimidazolium tetrafluoroborate ([BMIM][BF(4)]). Our experiments showed that the ionic liquid played an important role in the morphology of M(2)S(3) (M = Bi, Sb). Single-crystalline Bi(2)S(3) nanorods could be prepared in the presence of [BMIM][BF(4)]. However, urchinlike Bi(2)S(3) structures consisting of nanorods were formed without using [BMIM][BF(4)]. Single-crystalline Sb(2)S(3) nanorods were obtained in the presence of [BMIM][BF(4)]. However, single-crystalline Sb(2)S(3) nanosheets could be prepared in the absence of [BMIM][BF(4)]. The products were characterized by X-ray powder diffraction (XRD), transmission electron microscopy (TEM), and electron diffraction (ED).     

球磨-溶剂热诱导法合成WS2纳米棒及其摩擦性能

采用行星式高能球磨机，将WS₂与S粉末混合球磨，得到纳米片状结构的前驱体，然后添加分散剂聚乙二醇(PEG)用溶剂热诱导的方法使纳米片状前驱体发生结构转变，制备了棒状结构的WS₂纳米材料。用XRD、SEM、TEM等方法对WS₂纳米棒进行了形貌和结构表征，并对其作为润滑油添加剂的摩擦性能进行了初步的研究。     

Development of one-dimensional nanostructures through the crystallization of amorphous colloids

In this paper we have demonstrated that the crystallization method of amorphous colloids is convenient and feasible in the large-scale production of one-dimensional (1D) nanostructures. For the crystals with highly anisotropic structures, such as orthorhombic, trigonal, and hexagonal crystals, the crystallization generally tends to occur along the (001) axis. The preparation of orthorhombic bismuth sulfide (Bi2S3) nanorods and trigonal selenium ( t-Se) nanowires by the crystallization route was used as typical examples to illustrate the process and mechanism of crystallization. The as-prepared products were characterized with transmission electron microscopy, field-emission scanning electron microscopy, X-ray diffraction, and selected area electron diffraction. Additionally, the detailed crystal growth processes involved in the crystallization of amorphous Bi2S3 colloid were investigated by studying the morphology and structure of intermediates. It demonstrates that the growth of the nanorods is through two key steps: (1) the formation of multiple activated sites on the surface of spherical Bi2S3 colloid and (2) the subsequent preferential growth along these sites.     

Biomolecule-assisted synthesis and electrochemical hydrogen storage of Bi2S3 flowerlike patterns with well-aligned nanorods

Bi2S3 flowerlike patterns with well-aligned nanorods were synthesized using a facile solution-phase biomolecule-assisted approach in the presence of L-cysteine (an ordinary and cheap amino acid), which turned out to serve as both the S source and the directing molecule in the formation of bismuth sulfide nanostructures. Emphatically, no nauseous scent (H2S) appeared in our experiments, which could not be avoided in other previous reports. The morphology, structure, and phase composition of the as-prepared Bi2S3 products were characterized using various techniques (scanning electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy, transmission electron microscopy, selected area electron diffraction, and high-resolution transmission electron microscopy). The formation mechanism for the bismuth sulfide flowerlike assemblies with well-arranged nanorods was also discussed. In addition, other Bi2S3 homogeneous nanostructures (e.g., networklike nanoflakes, nanorod-based bundles, and nanoflakes) were obtained through varying the experimental parameters. Interestingly, we have found that these synthesized bismuth sulfide nanostructures using the biomoleucle-assisted approach could electrochemically charge and discharge with the capacity of 142 (mA h)/g (corresponding to 0.51 wt % hydrogen in single-walled carbon nanotubes) under normal atmosphere at room temperature. A novel two-plateau phenomenon was observed in the synthesized Bi2S3 nanostructures, suggesting that there were two independent steps in the charging process. It has been demonstrated that the bismuth sulfide's morphology and the constant charge-discharge current density had a noticeable influence on their capacity of electrochemical hydrogen storage. These differences in hydrogen storage capacity are likely due to the size and density of space/pores as well as the morphology of different Bi2S3 nanostructures. The novel Bi2S3 nanomaterials may find potential applications in hydrogen storage, high-energy batteries, luminescence, optoelectronic and catalytic fields, as well as in the studies of structure-property relationships. This facile, environmentally benign, and solution-phase biomolecule-assisted method can be potentially extended to the preparation of other metal chalcogenides including FeS, CuS, NiS, PbS, MnS, and CoS nanostructures.     

Bi2S3 nanomaterials: morphology manipulation and related properties

The Bi(2)S(3) nanomaterials with various morphologies such as nanorods, nanowires, nanowire bundles, urchin-like microspheres and urchin-like microspheres with cavities have been successfully synthesized through a simple hydrothermal method. Experimental results indicate that sulfur sources play crucial roles in determining the morphologies of Bi(2)S(3) products. Moreover, formation mechanisms of different Bi(2)S(3) nanostructures are discussed based on understanding of the growth habit of Bi(2)S(3) crystal. Finally, we also studied the morphologies-dependent electrochemical and optical properties of the as-synthesized Bi(2)S(3) nanomaterials.     

离子液体中微波合成纳米结构的Bi2S3和Bi19Br3S27

在不同咪唑基离子液体中, 利用微波辅助法快速合成了不同形貌的Bi2S3纳米粒子和Bi19Br3S27纳米棒. 利用XRD, TEM和SEM对合成产物进行了结构和形貌的表征. 实验结果表明离子液体在合成过程中对产物的相结构和形貌发挥了重要的作用. 实验中还进一步考察了不同实验条件对产物形貌的影响. 对实验的合成机理进行了初步探讨. 对不同形貌和纳米结构的Bi2S3和Bi19Br3S27进行了UV-Vis光谱分析.     

生物分子辅助溶剂热合成硫化锑纳米棒

以SbCl3和L-胱氨酸为反应原料,采用溶剂热法在170℃反应12h,制得硫化锑(Sb2S3)纳米棒.X射线衍射(XRD)、能量分散光谱(EDS)和X射线光电子能谱(XPS)研究表明所得产物为典型的Sb2S3正交结构.场发射扫描电子显微镜(FESEM)和透射电子显微镜(TEM)研究显示,Sb2S3纳米棒长为3～6μm,平均直径约为150nm.讨论了不同反应时间对Sb2S3的形成及其形貌的影响,并根据实验结果对所合成的一维纳米棒可能的形成机理进行了简单的探讨.     

Sonochemical fabrication and characterization of stibnite nanorods

Regular stibnite (Sb(2)S(3)) nanorods with diameters of 20-40 nm and lengths of 220-350 nm have been successfully synthesized by a sonochemical method under ambient air from an ethanolic solution containing antimony trichloride and thioacetamide. The as-prepared Sb(2)S(3) nanorods are characterized by employing techniques including X-ray powder diffraction, X-ray photoelectron spectroscopy, scanning electron microscopy, energy-dispersive X-ray analysis, transmission electron microscopy, selected area electron diffraction, high-resolution transmission electron microscopy, and optical diffuse reflection spectroscopy. Microstructural analysis reveals that the Sb(2)S(3) nanorods crystallize in an orthorhombic structure and predominantly grow along the (001) crystalline plane. High-intensity ultrasound irradiation plays an important role in the formation of these Sb(2)S(3) nanorods. The experimental results show that the sonochemical formation of stibnite nanorods can be divided into four steps in sequence: (1) ultrasound-induced decomposition of the precursor, which leads to the formation of amorphous Sb(2)S(3) nanospheres; (2) ultrasound-induced crystallization of these amorphous nanospheres and generation of nanocrystalline irregular short rods; (3) a crystal growth process, giving rise to the formation of regular needle-shaped nanowhiskers; (4) surface corrosion and fragmentation of the nanowhiskers by ultrasound irradiation, resulting in the formation of regular nanorods. The optical properties of the Sb(2)S(3) amorphous nanospheres, irregular short nanorods, needle-shaped nanowhiskers, and regular nanorods are investigated by diffuse reflection spectroscopic measurements, and the band gaps are measured to be 2.45, 1.99, 1.85, and 1.94 eV, respectively.     

Biomolecule-assisted synthesis of highly ordered snowflakelike structures of bismuth sulfide nanorods

A biomolecule-assisted simple technique has been developed for the spontaneous ordering of the Bi2S3 nanorods into snowflakelike superstructures in high yield under microwave-hydrothermal conditions. In this method, glutathione (GSH) is used as both an assembling agent and a sulfur source. By controlling the molar ratio between bismuth nitrate and glutathione as well as the synthetic temperature, several kinds of Bi2S3 one-dimensional nanomaterials such as snowflakelike structures, nanowires constructed of particles, short nanorods, and fine and long nanowires have been controllably synthesized.     

Monetite formed in mixed solvents of water and ethylene glycol and its transformation to hydroxyapatite

Agglomerated nanorods of hydroxyapatite have been synthesized using monetite as a precursor in a NaOH solution. Monetite consisting of nanosheets has been successfully synthesized by a one-step microwave-assisted method using CaCl(2).2.5H(2)O, NaH(2)PO(4), and sodium dodecyl sulfate (SDS) in water/ethylene glycol (EG) mixed solvents. The effects of the molar ratio of water to EG and the reaction time on the products were investigated. The products were characterized by X-ray powder diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and Fourier transform infrared spectrometry (FTIR).     

Controllable synthesis of NiC2O4·2H2O nanorods precursor and applications in the synthesis of nickel-based nanostructures

A controllable synthesis of NiC₂O₄·2H₂O nanorods precursor was obtained via the microemulsion-mediated solvothermal method and a further synthesis of β-Ni(OH)₂ nanorods, nickel oxide (NiO) sub-microtubes, Ni nanospheres and flower-like nickel complexes nanostructures by using the precursor. The morphologies and crystalline structures were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), selected area electron diffraction (SAED), and the X-ray powder diffraction (XRD). The morphologies and sizes of the precursors can be readily tuned by adjusting experimental parameters of the reverse microemulsion system. The synthesized β-Ni(OH)₂ nanorods composed of fine nanosheets shown excellent electrochemical performance as an electrode material in rechargeable battery systems.     

Controlled synthesis of olive-shaped Bi2S3/BiVO4 microspheres through a limited chemical conversion route and enhanced visible-light-responding photocatalytic activity

Well-defined olive-shaped Bi(2)S(3)/BiVO(4) microspheres were synthesized through a limited chemical conversion route (LCCR), where olive-shaped BiVO(4) microspheres and thioacetamide (TAA) were used as precursors and sulfur source, respectively. The as-synthesized products were characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), high-resolution transmission microscope (HRTEM), X-ray photoelectron spectra (XPS), UV-visible diffuse-reflectance spectroscopy (UV-vis DRS), and photoluminescence (PL) spectra in detail. Compared with pure BiVO(4) microspheres and Bi(2)S(3) nanorods, the Bi(2)S(3)/BiVO(4) products showed obviously enhanced photocatalytic activity for the degradation of rhodamine B (Rh B) in aqueous solution under visible-light irradiation (λ > 400 nm). In addition, the Bi(2)S(3)/BiVO(4) composite microspheres showed good visible-light-driven photocatalytic activity for the degradation of refractory oxytetracycline (OTC) as well. On the basis of UV-vis DRS, the calculated energy band positions, and PL spectra, the mechanism of enhanced photocatalytic activity of Bi(2)S(3)/BiVO(4) was proposed. The present study provides a new strategy to design composite materials with enhanced photocatalytic performance.     

Sb2S3纳米粒子修饰ZnO纳米片微纳分级结构的光电化学性能

采用恒电位方法,选择氯化钾和乙二胺(EDA)为添加剂,在氧化铟锡(ITO)导电玻璃上制备了高度有序的ZnO纳米片阵列,通过二次电沉积得到了ZnO纳米片上生长纳米棒的微纳分级结构.利用化学浴沉积法在ZnO基底上沉积Sb₂S₃纳米粒子制备出了Sb₂S₃/ZnO纳米片壳核结构和Sb₂S₃/ZnO微纳分级壳核结构.利用扫描电子显微镜(SEM)、X射线衍射(XRD)、紫外-可见(UV-Vis)吸收光谱、瞬态光电流等对其形貌、结构组成和光电化学性能进行了表征和分析.结果表明, Sb₂S₃/ZnO纳米片上生长纳米棒分级壳核结构的光电流明显高于Sb₂S₃/ZnO纳米片壳核结构.在Sb₂S₃/ZnO纳米片壳核结构和Sb₂S₃/ZnO微纳分级壳核结构的基础上旋涂一层P3HT薄膜形成P3HT/Sb₂S₃/ZnO复合结构,以上述复合结构薄膜为光活性层组装成杂化太阳电池,其中, P3HT/Sb₂S₃/ZnO分级壳核结构杂化太阳电池的能量转换效率最高,达到了0.81%.     

Dual function of rare earth doped nano Bi(2)O(3): white light emission and photocatalytic properties

Undoped Bi(2)O(3) and single and double doped Bi(2)O(3)?:?M (where M = Tb(3+) and Eu(3+)) nanophosphors were synthesized through a simple sonochemical process and characterized by using X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), high resolution transmission electron microscopy (HRTEM), EDS, diffuse reflectance (DRS) and photoluminescence (PL) spectrophotometry. The TEM micrographs show that resultant nanoparticles have a rod-like shape. Energy transfer was observed from host to the dopant ions. Characteristic green emissions from Tb(3+) ions and red emissions from Eu(3+) ions were observed. Interestingly, the Commission International de l'Eclairage (CIE) coordinates of the double doped Bi(2)O(3)?:?Eu(3+)(0.8%)?:?Tb(3+)(1.2%) nanorods lie in the white light region of the chromaticity diagram and it has a quantum efficiency of 51%. The undoped Bi(2)O(3) showed a band gap of 3.98 eV which is red shifted to 3.81eV in the case of double doped Bi(2)O(3)?:?Eu(3+)(0.8%)?:?Tb(3+)(1.2%) nanorods. The photocatalytic activities of undoped nano Bi(2)O(3) and double doped nano Bi(2)O(3)?:?Eu(3+)(0.8%)?:?Tb(3+)(1.2%) were evaluated for the degradation of Rhodamine B under UV irradiation of 310 nm. The results showed that Bi(2)O(3)?:?Eu(3+)(0.8%)?:?Tb(3+)(1.2%) had better photocatalytic activity compared to undoped nano Bi(2)O(3). The evolution of CO(2) was realized and these results indicated the continuous mineralization of rhodamine B during the photocatalytic process. Thus double doped Bi(2)O(3)?:?Eu(3+)(0.8%)?:?Tb(3+)(1.2%) nanorods can be termed as a bifunctional material exhibiting both photocatalytic properties and white light emission.     

From Zn-Al layered double hydroxide to ZnO nanostructure:Gradually etching by sodium hydroxide

Zn-Al layered double hydroxide(LDH) was used as precursor to produce ZnO nanostructures through dissolution of aluminum hydroxide in caustic soda.The Zn-Al LDH could transform into different nanostructures of ZnO on LDH nanosheets and even pure ZnO nanorods under various NaOH concentration.The formed ZnO nanorods vertically aligned on both LDH sides.UV-vis diverse reflectance spectra show that the obtained ZnO nanorods have a band gap of approximately 3.05 eV.Such ZnO/LDH nanostructures might be used as photocatalyst in the organic pollutant decomposition.     

Synthesis and growth mechanism of Bi2S3 nanoribbons

This article describes a facile solvothermal method by using mixed solvents for the large-scale synthesis of Bi(2)S(3) nanoribbons with lengths of up to several millimeters. These nanoribbons were formed by a solvothermal reaction between Bi(III)-glycerol complexes and various sulfur sources in a mixed solution of aqueous NaOH and glycerol. HRTEM (high-resolution transmission electron microscopy) and SAED (selective-area electron diffraction) studies show that the as-synthesized nanoribbons had predominately grown along the [001] direction. The Bi(2)S(3) nanoribbons prepared by the use of different sulfur sources have a common formation process: the initial formation of NaBiS(2) polycrystals, which serve as the precursors to Bi(2)S(3), the decomposition of NaBiS(2), and the formation of Bi(2)S(3) seeds in the solution through a homogeneous nucleation process; the growth of Bi(2)S(3) nanoribbons occurs at the expense of NaBiS(2) materials. The growth mechanism of millimeter-scale nanoribbons involves a special solid-solution-solid transformation as well as an Ostwald ripening process. Some crucial factors affect nanoribbon growth, such as, solvothermal temperature, volume ratio of glycerol to water, and the concentration of NaOH; these have also been discussed.     

Morphology-Dependent Peroxidase Mimicking Enzyme Activity of Copper Metal-Organic Polyhedra Assemblies

The morphology of nanomaterials (geometric shape and dimension) play a significant role in its various physical and chemical properties. Thus, it is essential to link morphology with performance in specific applications. For this purpose, the morphology of copper metal–organic polyhedra (Cu-MOP) can be modulated through distinct assembly process, which facilitates the exploration of the relationship between morphology and catalytic performance. In this work, the assemblies of Cu-MOP with three different morphologies (nanorods, nanofibers and nanosheets) were facilely prepared by the variation of solvent mixture of N, N-dimethylformamide (DMF) and methanol, revealed the important role of the interaction between the surface group and the solvent on the morphology of these assemblies. Cu-MOP nanofibers exhibited the highest mimetic peroxidase enzyme activity over the Cu-MOP nanosheets and nanorods, which have been utilized in the detection of glucose. Cu-MOPs assemblies with tunable morphology accompanied with adjustable mimic peroxidase activity, had great potential applications in the field of bioanalytical chemistry and biomedicals.     

Bi2S3-sensitized TiO2 nanorods by bottom-up approach for photoelectrochemical solar cell

Journal of Solid State Electrochemistry - Bismuth sulfide (Bi2S3)-sensitized titanium dioxide (TiO2) nanorods have been successfully synthesized by a simple and cost-effective chemical deposition...     

High-yield synthesis of quantum-confined CdS nanorods using a new dimeric cadmium(II) complex of S-benzyldithiocarbazate as single-source molecular precursor

A convenient solvothermal single-source route has been developed for the bulk synthesis of CdS nanorods using new air stable dimeric cadmium(II) complex of S-benzyldithiocarbazate, [Cd(PhCH₂SC(S)NHNH₂)Cl₂]₂, at a relatively low temperature. The decomposition of the precursor was made by heating at 160 °C in hexamethylenediamine (HMDA) to give amine capped CdS nanocrystals having yield ca. 90%; nano-dimensional rods are clearly visible in transmission electron microscope (TEM). The nanorods have been further characterized by X-ray diffraction (XRD), energy dispersed X-ray spectroscopy (EDX), FTIR and optical measurements. The structure of precursor was also established by single crystal X-ray crystallography.     

Top-down fabrication of crystalline metal-organic framework nanosheets

Crystalline metal-organic framework (MOF) nanosheets have been fabricated via top-down delamination from bulk crystals of a layered MOF, {Zn(TPA)(H(2)O)·DMF}(n) (MOF-2), and characterized by Tyndall scattering, scanning electron microscopy and atomic force microscopy measurements. The delaminated MOF-2 nanosheets exhibit remarkable amine intercalation property and reversible amine exchangeability.