The facile synthesis of PbS cubes and Bi2S3 nanoflowers from molecular precursors at room temperature

PbS and Bi₂S₃ nanocrystals with well-controlled sizes and shapes were easily produced from molecular precursors (xanthate) in ethylene diamine (en) solution at room temperature. When lead or bismuth ethylxanthate were added into en solution, the precipitates were instantly formed, and subsequently, PbS cubes and flower-like Bi₂S₃ hierarchical structures were obtained if the mixtures were left still for 5 days under ambient conditions. This work not only provides a facile route to synthesize chalcogenides with well-defined nano- and microstructures in a solution-phase system, but also gives insight into understanding on decomposition behavior of molecular precursors in various solvents.     

A facile photochemical route for the synthesis of gold nanoparticles

Synthesis of high-quality, water-dispersed gold nanoparticles (AuNPs), has been prepared employing luminol as a special reductant, via direct irradiation of the molecular precursors rather than traditional heat of the solvent. The final quality of the photochemically generated nanomaterial was characterized by transmission electron microscopy, resonance light scattering spectra, and cyclic voltammetry. AuNPs could enhance the chemiluminescence intensity of the luminol-H₂O₂ system, attributing to their catalysis. On the basis, we developed a nanoparticle-based chemiluminescence method for the determination of H₂O₂. The results demonstrated that it was possible to detect hydrogen peroxide in the range of 10⁻⁸–10⁻³ M.     

A facile solution phase synthesis of directly ordering monodisperse FePt nanoparticles

The ordered Pt-based intermetallic nanoparticles(NPs)with small size show superior magnetic or catalytic properties,but the synthesis of these NPs still remains a great challenge due to the requirement of high temperature annealing for the formation of the ordered phase,which usually leads to sintering of the NPs.Here,we report a simple approach to directly synthesize monodisperse ordered L1₀-FePt NPs with average size 10.7 nm without further annealing or doping the third metal atoms,in which hexadecyltrimethylammonium chloride(CTAC)was found to be the key inducing agent for the thermodynamic growth of the Fe and Pt atoms into the ordered intermetallic structure in the synthetic process.In particular,10.7 nm L1₀-FePt NPs synthesized by the proper amount of CTAC show a coercivity of 3.15 kOe and saturation magnetization of 45 emu/g at room temperature.The current CTAC-assisted synthetic strategy makes it possible to deeply understand the formation of the ordered Pt-based intermetallic NP in solution phase synthesis.     

Growth and properties of CuInS2 single crystals

CuInS₂ single crystals 14–16 mm in diameter and up to 40 mm in length were grown by the traveling solvent method. The crystals were found to ben-type, with a conductivity of 0.1–10 S/cm, carrier concentration of 10¹⁶–10¹⁷ cm⁻³, and carrier mobility of 150–220 cm²/(V s). The anisotropic thermal expansion of the crystals was measured.     

Solvothermal synthesis of CuInS2 powders and CuInS2 thin films for solar cell application

In this study, a facile solvothermal method was developed to prepare CuInS₂ powders and CuInS₂ thin films. The CuInS₂ powders and CuInS₂ thin films were prepared by solvothermal route using the precursor of Copper (II) chloride, indium (III) nitrate, thiourea, oxalic acid, hexadecyl trimethyl ammonium bromide and ethanol. The morphology, crystallographic structure, chemical composition and optical band gap of CuInS₂ powders and CuInS₂ thin films were investigated using scanning electronic microscope (SEM), X-ray diffraction (XRD), energy dispersive spectrometry (EDS) and UV–vis spectroscopy. The results reveal that both CuInS₂ powders and CuInS₂ thin films are in chalcopyrite phase. The CuInS₂ powders are mainly composed of flower-like microspheres. Both microstructure of the sphere surface and diameter of sphere are affected by indium nitrate concentration in precursors. The CuInS₂ thin films are composed of a large number of uniform flower-like nanosheets, and the nanosheets become smaller in size and denser in distribution density with increasing concentration of thiourea. The optical band gap is found to be 1.44 and 1.52 eV for CuInS₂ powders and CuInS₂ thin films, respectively. The deposition mechanism of the CuInS₂ is discussed.     

Effect of aluminum source on the synthesis of AlN powders from combustion synthesis precursors

In the present work, the carbothermal reduction method was employed to fabricate the AlN powders by utilizing the combustion synthesized precursor derived from the mixed solution comprised of an aluminum source (Al(NO₃)₃ or Al₂(SO₄)₃ or AlCl₃), glucose, nitric acid, and urea. Effects of aluminum source on the particle size and morphology of precursors as well as synthesized AlN powders were studied in detail. The size and morphology of precursors, derived from various aluminum sources, had exhibited significant differences. The precursor from Al(NO₃)₃ source had completed the nitridation reaction at 1500 °C in 2 h. However, the nitridation reactions of the precursors from Al₂(SO₄)₃ or AlCl₃ source furnished at increased temperature of 1550 °C in 2 h. Moreover, the AlN powders from various aluminum sources have been synthesized directly from γ-Al₂O₃ without γ-Al₂O₃ to α-Al₂O₃ phase transition. The AlN powders from Al(NO₃)₃, calcined at 1550 °C for 2 h, were comprised of well-distributed spherical particles with an average size of 80 nm. While the AlN powders from AlCl₃ or Al₂(SO₄)₃ consisted of heterogeneously distributed spherical particles ranging from 100 to 200 nm or from 80 to 150 nm, respectively.     

A facile synthesis of monodisperse Au nanoparticles and their catalysis of CO oxidation

Monodisperse Au nanoparticles (NPs) have been synthesized at room temperature via a burst nucleation of Au upon injection of the reducing agent t-butylamine-borane complex into a 1, 2, 3, 4-tetrahydronaphthalene solution of HAuCl₄·3H₂O in the presence of oleylamine. The as-synthesized Au NPs show size-dependent surface plasmonic properties between 520 and 530 nm. They adopt an icosahedral shape and are polycrystalline with multiple-twinned structures. When deposited on a graphitized porous carbon support, the NPs are highly active for CO oxidation, showing 100% CO conversion at −45 °C. This article is published with open access at Springerlink.com     

A facile and novel way for the synthesis of nearly monodisperse silver nanoparticles

A facile and novel way was reported for the preparation of nearly monodisperse silver nanoparticles with controlled hydrophilic or hydrophobic surface, using trioctylphosphine as the surfactant and stabilizer. The synthesized nanoparticles were characterized by transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HRTEM), selected area electron diffraction (SAED) and UV-vis spectroscopy. The monodisperse silver nanoparticles showed a strong surface plasmon resonance band at 402 nm from the UV-vis spectrum.     

Ag-catalyzed synthesis of ultrafine nickel nanoparticles: A facile way to size control

We report here a facile strategy, Ag-catalyzed reduction of Ni²⁺ ions, for the synthesis of metallic nickel nanoparticles. The phase structure and morphology of particles were analyzed by means of X-ray diffraction and scanning electron microscopy. It was found that the resultant Ni nanoparticles had narrow size distribution, and the control of particle size could be easily achieved through manipulation of the molar ratio between nickel salts and silver seeds. XRD analysis of the final particles showed the crystalline nickel structure and the presence of metallic Ag, which was influenced by the Ni/Ag molar ratio. The effects of reduction temperature on the final particle size were also investigated.     

A facile route to synthesis of AgInS2 nanostructures

AgInS₂ nanoparticles have been synthesized via a facile one-step process using AgNO₃, thiosemicarbazid (TSC) and InCl₃·4H₂O as starting reagents from propylene glycol solution. The effects of concentration of precursors, reaction time and type of sulfur sources on the morphology and particle size were also studied. X-ray diffraction (XRD), energy dispersive X-ray analysis (EDX), scanning electron microscope (SEM), transmission electron microscope (TEM), ultraviolet-visible spectroscopy (UV-Vis) and photoluminescence (PL) spectroscopy were used to characterize the obtained products.     

A facile novel synthesis of delafossite CuFeO2 powders

P-type transparent conducting oxides copper delafossite CuFeO₂ powders have been successfully synthesized by using hydrothermal method. The influence of synthesis conditions on the crystal structure, morphology, optical and magnetic properties was systematically studied using X-ray diffraction, scanning electron microscope (SEM), UV–Vis–NIR scanning spectrophotometer and vibrating sample magnetometer. The results indicated the precipitated precursor at pH value of 12 using 1 M NaOH as a base in the presence of hydrazine hydrate as a reducing agent hydrothermally treated at 280 °C for 96 h was transformed to pure rhombohedral 3R delafossite phase. SEM observations of these powders confirmed their hexagonal like structure. The transmittance of the sample was around 65 %. The optical band gap of delafossite–CuFeO₂ sample prepared was 3.5 eV as a visible transparent material. Furthermore, magnetic properties behavior was identified and paramagnetism property was found at a room temperature. The saturation magnetization and coercive force for the pure sample were 1.2 emu/g and 58.35 Oe, respectively.     

Synthesis of WS2 and MoS2 fullerene-like nanoparticles from solid precursors

Inorganic fullerene-like WS₂ and MoS₂ nanoparticles have been synthesized using exclusively solid precursors, by reaction of the corresponding metal oxide nanopowder, sulfur and a hydrogen-releasing agent (NaBH₄ or LiAlH₄), achieved either by conventional furnace heating up to ∼900 °C or by photothermal ablation at far higher temperatures driven by highly concentrated white light. In contrast to the established syntheses that require toxic and hazardous gases, working solely with solid precursors permits relatively safer reactor conditions conducive to industrial scale-up.      

由有机和无机金属前躯体自蔓延高温合成碳包覆磁纳米粒子(英文)

介绍了一项由自蔓延高温合成(SHS)碳包覆磁纳米粒子的系统研究。采用还原剂NaN3和三种不同氧化剂-聚四氟乙烯、六氯乙烷和六氯苯,实施了SHS制备。研究了金属前躯体(Fe(CO)5或K3[Fe(CN)6])对产物的得率、反应热、形貌、结构和磁性能的影响。结果表明:有机铁前躯体和C2Cl6氧化剂反应体系可获得磁性最佳、得率最高的产物。     

A facile synthesis of lipid stabilized gold nanoparticles: a step towards biodegradable biosensors

A new class of polylactone was successfully synthesized and utilized for the encapsulation and stabilization of gold nanoparticles. Core/shell nanoparticle architecture, in which a layer of this polymer surrounds the nanoparticle core have been investigated both as a means to improve the stability and surface chemistry and as a way of accessing unique physical properties that are not possible from one nano-material alone. Given the fact that only few systems has so far been developed for the encapsulation of nanoparticles, our success in using a new biodegradable biopolymer with inbuilt functionality reveals the robustness of this work. The biodegradability of this polylactone was evaluated using scanning electron microscopy (SEM). The morphology and stability of these gold-polymer hybrids were evaluated by using the transmission electron microscopy (TEM) and UV-VIS spectroscopy.     

A facile, clean and quantitative synthesis of antimony chloride oxide single crystals

The single crystals of antimony chloride oxide (Sb₄O₅Cl₂) were directly obtained through a hydrothermal reaction of SbCl₃ in a diluted aqueous HCl solution at 140 °C for about 30 h and the yield was as high as 99%. The only by-product of this route was HCl, which could be recycled. The purity of the crystals was highly approved by XRD, XPS, elemental analysis and the X-ray single crystal structural analysis.     

A facile and fast approach for the synthesis of doped nanoparticles using a microfluidic device

The microfluidic approach emerges as a new and promising technology for the synthesis of nanomaterials. A microreactor allows a variety of reaction conditions to be quickly scanned without consuming large amounts of raw material. In this study, we investigated the synthesis of water soluble 1-thioglycerol-capped Mn-doped ZnS nanocrystalline semiconductor nanoparticles (TG-capped ZnS:Mn) via a microfluidic approach. This is the first report for the successful doping of Mn in a ZnS semiconductor at room temperature as well as at 80?°C using a microreactor. Transmission electron microscopy and x-ray diffraction analysis show that the average particle size of Mn-doped ZnS nanoparticles is ～3.0?nm with a zinc-blende structure. Photoluminescence, x-ray photoelectron spectroscopy, atomic absorption spectroscopy and electron paramagnetic resonance studies were carried out to confirm that the Mn(2+) dopants are present in the ZnS nanoparticles.