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1.
The urchin-like Bi2S3 nanostructures have been grown by a facile environmentally friendly hydrothermal method. X-ray diffraction (XRD) and Raman spectrum demonstrate that the obtained samples are composed of pure orthorhombic phase Bi2S3. Scanning electron microscopy (SEM) images and transmission electron microscopy (TEM) images reveal that it is produced as uniform urchin-like pattern with spherical symmetry. High-resolution (HR) TEM and selected-area electron diffraction (SAED) demonstrate that the nanowires which grow radially from the center of the urchin-like nanostructures toward all directions are single-crystalline and grow along the [001]. It is found that the reaction time, reaction temperature and thiourea (Tu) play key roles for the formation of urchin-like Bi2S3 nanostructures. The formation mechanism is ascribed to self-assembly and the intrinsic splitting character of the Bi2S3 structure. The urchin-like Bi2S3 composed of porous nanorods, solid nanorods and nanowires could be found potential application in optical, catalysts and sensor devices.  相似文献   

2.
This report focuses on the synthesis of gold‐nickel bimetallic nanostructures. In the presence of amine as the capping agent, thermal decomposition of organometallic precursors CH3AuPPh3 and Ni(PPh3)4 in o‐xylene offered AuNi nanorods. Several preparative parameters possible influencing the morphology of the structure were carefully studied by varying the reaction conditions with respect to the standard procedure. The morphology and composition of the AuNi nanorods were principally characterized by transmission electron microscopy, energy dispersive spectroscopy, and powder X‐ray diffraction. The distribution of the Au as well as Ni atoms was examined by EDS mapping analysis. The mechanism of the formation of the AuNi bimetallic nanorods is proposed on the base of observation of the morphologies of nanostructures at various reaction time intervals.  相似文献   

3.
利用溶剂热法在不同反应溶剂中制备了不同尺寸的Bi2S3纳米管和纳米棒.利用XRD、SEM、TEM、选区电子衍射(SAED)和高分辨透射电镜(HRTEM)对其结构和形貌进行了表征.结果表明,所制备的产物是结晶良好的正交相Bi2S3,反应溶剂的表面张力、粘度大小和反应溶剂中的比例影响纳米粉体的形貌和尺寸.紫外-可见光吸收光谱测量表明,由于尺寸效应所有粉体的吸收谱相对于正交相的Bi2S3块体都出现蓝移.  相似文献   

4.
Graphite‐nanoplate‐coated Bi2S3 composite (Bi2S3@C) has been prepared by a simple, scalable, and energy‐efficient precipitation method combined with ball milling. The Bi2S3@C composite was used as the cathode material for sodium–sulfide batteries. It delivered an initial capacity of 550 mAh g?1 and high stable specific energy in the range of 275–300 Wh kg?1 at 0.1 C, with an enhanced capacity retention of 69 % over 100 cycles. The unique structure demonstrates superior cycling stability, with a capacity drop of 0.3 % per cycle over 100 cycles, compared with that of bare Bi2S3. The sodium storage mechanism of Bi2S3 was investigated based on ex situ X‐ray diffraction and scanning transmission electron microscopy.  相似文献   

5.
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.  相似文献   

6.
A low-temperature solution-phase method has been demonstrated for the synthesis of uniform nanorods of Bi2S3 with diameter of 18 nm and length of below 200 nm. Transmission electron microscopy (TEM), selected-area electron diffraction (SAED), and X-ray diffraction (XRD) studies revealed that these nanorods were grown from a colloidal dispersion of amorphous Bi2S3 particles, which was first formed through a thermal reaction between Bi-thiol complexes Bi(SC12)3 and thioacetamide (TAA) in a pure dodecanethiol (C12SH) solvent at a temperature of 95 °C. Based on these studies, the growth mechanism of Bi2S3 nanorods was properly proposed.  相似文献   

7.
Hexagonal tungsten oxide nanorods have been synthesized by hydrothermal strategy using Na2WO4·2H2O as tungsten source, aniline and sulfate sodium as structure-directing templates. Techniques X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HRTEM), Fourier transform infrared spectroscopy (FTIR) and Raman spectroscopy have been used to characterize the structure, morphology and composition of the nanorods. The h-WO3 nanorods are up to 5 μm in length, and 50–70 nm in diameter.  相似文献   

8.
Well-segregated bismuth sulfide (Bi2S3) nanorods with a high order of crystallinity have been successfully prepared from bismuth(III) monosalicylate [BiO(C7H5O3)] by a simple hydrothermal reaction in H2O at 180 °C. Bismuth(III) monosalicylate and thioglycolic acid act as the starting materials. The products were characterized by powder X-ray diffraction, Ultraviolet–Visible (UV–Vis) spectroscopy, transmission electron microscopy photoluminescence spectroscopy, and Fourier transform infrared spectra. The powder X-ray diffraction pattern shows the product belongs to the orthorhombic Bi2S3 phase. Their UV–Vis spectrum shows the absorbance at 328 nm, with its direct energy band gap of 2.6 eV. Bismuth salicylate, which is known to be a complex, may play a critical role as a precursor and a template for the growth of linear bismuth sulfide nanorods. Finally the influences of the reaction conditions are discussed and a possible mechanism for the formation of Bi2S3 nanorods is proposed.  相似文献   

9.
Self‐assembled Bi2Te3 one‐dimensional nanorod bundles have been fabricated by a low‐cost and facile solvothermal method with ethylene diamine tetraacetic acid as an additive. The phase structures and morphologies of the samples were characterized by X‐ray diffraction, scanning electron microscopy, Fourier‐transform infrared spectrometry, and transmission electron microscope measurements. The growth mechanisms have been proposed based on the experimental results. The full thermoelectric properties of the nanorod bundles have been characterized and show a large improvement in the thermal conductivity attributed to phonon scattering of the nanostructures and then enhance the thermoelectric figure of merit. This work is promising for the realization of new types of highly efficient thermoelectric semiconductors by this method.  相似文献   

10.
通过溶胶-凝胶法以十八烷基三甲基溴化铵(STAB)自组装体为模板和非离子型联二萘酚衍生物(S)作为手性添加剂制备螺旋介孔二氧化硅。样品利用扫描电镜、透射电镜、X-光衍射以及氮气吸附-脱附进行了表征。结果表明:反应混合物中S与STAB的物质的量之比对介孔二氧化硅的形貌及孔结构有很大影响。改变nSnSTAB比,从0.1:1到0.4:1时,其结构从螺旋纳米棒状变为表面具有环形层状孔的纳米棒,孔道由沿着纳米棒长轴方向转变为同心环状。当nSnSTAB=0.5:1时,得到类似皱缩花瓣的纳米颗粒。该手性添加剂的引入并没有改变左右手螺旋纳米棒的比例。  相似文献   

11.
通过溶胶-凝胶法以十八烷基三甲基溴化铵(STAB)自组装体为模板和非离子型联二萘酚衍生物(S)作为手性添加剂制备螺旋介孔二氧化硅。样品利用扫描电镜、透射电镜、X-光衍射以及氮气吸附-脱附进行了表征。结果表明:反应混合物中S与STAB的物质的量之比对介孔二氧化硅的形貌及孔结构有很大影响。改变nS∶nSTAB比,从0.1∶1到0.4∶1时,其结构从螺旋纳米棒状变为表面具有环形层状孔的纳米棒,孔道由沿着纳米棒长轴方向转变为同心环状。当nS∶nSTAB=0.5∶1时,得到类似皱缩花瓣的纳米颗粒。该手性添加剂的引入并没有改变左右手螺旋纳米棒的比例。  相似文献   

12.
以硝酸锌[Zn(NO3)2.6H2O]和尿素[CO(NH2)2]作前驱体,通过微波诱导燃烧技术可控合成具有不同形貌的ZnO纳米晶体,并用热重分析和差热分析进行了研究。对各种生长条件:微波功率,辐射时间和尿素/Zn2+物质的量的比对ZnO纳米晶体形貌的影响作了分析。结果表明:尿素/Zn2+物质的量的比对ZnO纳米材料的形貌具有显著影响。X衍射图表明合成的ZnO纳米结构呈六角形。傅里叶变换红外光谱图中400~500 cm-1处明显的峰为Zn-O的振动峰。ZnO纳米结构的发光光谱在366 nm的带边发射,因缺陷又由许多可见光发射峰组成。用扫描电子显微镜、透射电子显微镜、选区电子衍射研究了花状ZnO纳米结构的增长机理。本方法仅需几分钟就获得的了ZnO纳米结构。  相似文献   

13.
Various morphologies of ZnO nanostructures, such as nanoparticles, nanorods and nanoflowers have been achieved controllably by polymeric sol–gel method. In this approach, zinc nitrate Zn(NO3)2·6H2O, citric acid and ethylene glycol were used as the source of Zn2+, the chelating agent and the solvent agent, respectively. The microstructure of the ZnO nanostructures was characterized by X-ray diffractometry, scanning electron microscopy with the energy dispersive X-ray spectroscopy, transmission electron microscopy, thermogravimetric analysis and Fourier transform infrared spectroscopy. The effect of ethylene glycol to citric acid mole ratio on the morphology and structure of the products was discussed. The ZnO nanoparticles with diameter between 24 ± 2 nm was obtained with EG:CA mole ratio equal to 2:1. The optical properties of as-obtained power were investigated by ultraviolet–visible spectroscopy.  相似文献   

14.
FeMoO4 nanorods and their rare earth (Eu3+ and Tb3+) doped composites with nitrogen doped graphene (NG) were synthesized by facile hydrothermal method in aqueous medium. X-ray diffraction (XRD) analysis of the as-synthesized samples was done to study the phase purity and crystalline nature. FTIR and Raman Spectroscopy have been studied for investigating the bonding in nanostructures. The surface morphology of the samples was investigated with field emission scanning electron microscopy (FE-SEM) and transmission electron microscopy (TEM). The photolumniscent nature of the samples was investigated by the using the fluorescence spectrophotometer. The photocatalytic degradation efficiency of the prepared pure FeMoO4 and its rare earth doped composites with nitrogen doped graphene was evaluated as function of visible light irradiation versus concentration of methylene blue (MB dye). The prepared nanocomposites show enhanced photocatalytic efficiency as compared to the bare FeMoO4 nanorods.  相似文献   

15.
Fe3O4 anisotropic nanostructures that exhibit excellent catalytic performance are rarely used to catalyze Fenton‐like reactions because of the inevitable drawbacks resulting from traditional preparation methods. In this study, a facile, nontoxic, water‐based approach is developed for directly regulating a series of anisotropic morphologies of Fe3O4 nanostructures in a hydrogel matrix. In having the advantages of both the catalytic activity of Fe3O4 and the adsorptive capacity of an anionic polymer network, the hybrid nanocomposites have the capability to effect the rapid removal of cationic dyes, such as methylene blue, from water samples. Perhaps more interestingly, hybrid nanocomposites loaded with Fe3O4 nanorods exhibit the highest catalytic activity compared to those composed of nanoneedles and nanooctahedra, revealing the important role of nanostructure morphology. By means of scanning electrochemical microscopy, it is revealed that Fe3O4 nanorods can efficiently catalyze H2O2 decomposition and thus generate more free radicals (.OH, .HO2) for methylene blue degradation, which might account for their high catalytic activity.  相似文献   

16.
In this work, samples consisting of BiVO4 with exposed (040) facets coupled with Bi2S3 (Bi2S3/BiVO4) were prepared through a one-pot hydrothermal method, using ethylenediaminetetraacetic acid as directing agent and L-cysteine as sulfur source and soft template. X-ray diffraction, field emission scanning electron microscopy, and high-resolution transmission electron microscopy measurements indicated that the Bi2S3 content had a significant influence on the growth of (040) and (121) facets as well as on the morphology of the Bi2S3/BiVO4 samples. When the Bi2S3 content reached 1 mmol, the Bi2S3/BiVO4 samples exhibited a peony-like morphology. The results of transient photocurrent tests and electrochemical impedance spectroscopy measurements confirmed that a more effective charge separation and a faster interfacial charge transfer occurred in Bi2S3/BiVO4 than BiVO4. The enhanced photocatalytic activity of the Bi2S3/BiVO4 samples could be attributed to the improved absorption capability in the visible light region and the enhanced electron-hole pair separation efficiency due to the formation of the Bi2S3/BiVO4 heterostructure. In addition, the Bi2S3/BiVO4 samples showed relative stability and reusability. The simple method presented in this work could be used to fabricate composite photocatalysts with high activity for different applications, such as photocatalytic degradation of organic pollutants, photocatalytic splitting of water, and photocatalytic reduction of carbon dioxide.  相似文献   

17.
《Electroanalysis》2017,29(9):2027-2035
The ultra‐wide two dimensional Bi2S3 nanosheets (2D Bi2S3 Ns) as non‐toxic graphene‐like nanomaterials have been prepared through solvothermal decomposition of a single‐source precursor, Bi(S2CNEt2)3, in ethylenediamine media for 2 h in 180 °C. The morphology, structure, properties and catalytic activity of prepared 2D Bi2S3 Ns were characterized with XRD, field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), UV‐Visible spectroscopy, cyclic voltammetry (CV), amperometry, electrochemical charge/discharge technique and electrochemical impedance spectroscopy (EIS). The SEM image showed the 2D Bi2S3 Ns with a thickness of 15±4 nm and lengths of several micrometers is synthesized. The UV−Vis spectrum of 2D Bi2S3 Ns showed high sensitivity to visible‐near infrared light with its direct energy band gap of ≈1.22 eV. These Bi2S3 Ns showed high electron transfer ability and good electrochemical behavior and also exhibited electro‐catalytic activity toward the reduction‐oxidation of hydrogen peroxide. It is found that Bi2S3 Ns could detect H2O2 at wide linear concentration range (50.0 μM–8.0 mM) with detection limit 8 μM, using amperometry as measuring technique. Also the synthesized Bi2S3 Ns exhibited excellent electrochemical H2 storage properties. As a result, based on above properties, the Bi2S3 Ns can be used as a valuable and useful nanomaterial for H2 storage, high‐energy batteries, electrocatalytic fields and electrochemical sensing.  相似文献   

18.
PbS and Bi2S3 nanostructures were synthesized successfully via a microwave approach. For synthesis of PbS nanoparticles, a new precursor, [bis(salisylate) lead (ΙΙ)]; [Pb(Hsal)2] was used. The products were characterized by X-ray diffraction, scanning electron microscopy, and photoluminescence spectroscopy. Thin film of Bi2S3 was prepared by doctor’s blade technique and solar cell made from ITO/Bi2S3/PbS/Pt layers. I–V characterization was investigated for this cell and fill factor, open circuit voltage and short circuit current values were obtained.  相似文献   

19.
以Cu(NO_3)_2·3H_2O,H_2C_2O_4和Na_2S·9H_2O为原料,利用简易水热方法合成了笼状硫化铜空心球。所得产物用X射线衍射(XRD)、场发射扫描电子显微镜(FE-SEM)、透射电子显微镜(TEM)和高分辨透射电子显微镜(HRTEM)进行了表征,并研究了其可能的形成机理。所得CuS空心球具有较高的光热转换性能,在近红外光辐照下,对肿瘤细胞具有明显的光热毒性。  相似文献   

20.
One dimensional nanostructures of cerium doped dysprosium phosphate (DyPO4:Ce3+) were synthesized via hydrothermal route in the presence of different surfactants [sodium dodecyl sulfate (SDS), dodecyl sulfosuccinate (DSS), polyvinyl pyrollidone (PVP)] and solvent [ethylene glycol and water]. The prepared nanostructures were characterized by Powder X-ray diffraction (PXRD), Fourier transform infrared spectroscopy (FTIR), Field emission scanning electron microscopy (FE-SEM), Transmission electron microscopy (TEM), energy dispersive spectroscopy (EDS), UV-VIS-NIR absorption spectrophotometer and photoluminescence (PL) studies. The PXRD and FTIR results indicate purity, good crystallinity and effective doping of Ce3+ in nanostructures. SEM and TEM micrographs display nanorods, nanowires and nanobundles like morphology of DyPO4:Ce3+. Energy-dispersive X-ray spectra (EDS) of DyPO4:Ce3+nanostructures confirm the presence of dopant. UV-VIS-NIR absorption spectra of prepared compounds are used to calculate band gap and explore their optical properties. Luminescent properties of DyPO4:Ce3+ was studied by using PL emission spectra. The effect of additives and solvents on the uniformity, morphology and optical properties of the nanostructures were studied in detail.  相似文献   

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