共查询到20条相似文献,搜索用时 0 毫秒
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Masoud Salavati-Niasari Mahnaz Dadkhah Mohammad Reza Nourani Alireza Amini Fazl 《Journal of Cluster Science》2012,23(4):1011-1017
A simple thermal decomposition route has been developed to prepare single-phase cubic ZrO2 nanospheres by [Zr(sal)3(H2O)2](NO3) as the new precursor. The ZrO2 nanocrystals have been prepared by bis-aqua, tris-salicylaldehydato zirconium(IV) nitrate; [Zr(sal)3(H2O)2](NO3), as precursor in oleylamine (C18H37N) and triphenylphosphine (C18H15P). To control the particle size, combination of C18H37N and C18H15P were applied as surfactants. The C18H37N and C18H15P play an important role in preventing aggregation of ZrO2 nanocrystals. The products were characterized by X-ray diffraction, transmission electron microscopy, photoluminescence spectroscopy, and Fourier transform infrared (FT-IR) spectroscopy to depict the phase and morphology. The FT-IR spectrum showed the purity of obtained ZrO2 nanocrystals with cubic phase. 相似文献
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Xin‐Gui Li Prof. Dr. Ji Li Mei‐Rong Huang Prof. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2009,15(26):6446-6455
The straight dope : Polythiophene (PTh) nanoparticles with a narrow size distribution were successfully synthesized by a chemical oxidative polymerization (see image). The highest conductivity of virgin PTh is 3.1×10?4 S cm?1 and can be dramatically enhanced to 50 S cm?1 by doping in iodine vapor.
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A simple solvothermal approach was developed to synthesize uniform spherical monodisperse Ni nanoparticles, which can easily disperse in nonpolar solvents to form homogenous colloidal solution. The as-prepared sample was characterized by XRD, TEM, and FTIR. The results indicate that Ni nanoparticles have the structure of face-centered cube and a narrow distribution with a diameter of (3.5±0.5) nm. The FTIR spectrum reveals that the nanoparticles are coated with oleic acid. In the synthetic process, N2H4·H2O was used as a reducing agent and oleic acid as a surfactant. The probable formation mechanism of the spherical nanoparticles was also discussed. 相似文献
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立方介孔相含钇氧化硅的合成与表征 总被引:4,自引:0,他引:4
以低浓度的十六烷基三甲基溴化铵为结构导向剂,在碱性条件下通过水热法合成了具有立方结构的含钇Y MCM 48介孔分子筛材料。XRD测试表明当Y/Si<0.05时可以获得典型的长程有序介孔立方结构相,随Y/Si比的增加,晶胞参数的增大和红外吸收光谱(FTIR)的变化为Y进入介孔分子筛骨架中提供了有力证据。N2吸附-脱附实验给出这种立方介孔材料的BET表面积为1180m2·g-1,BJH平均孔径为3.4nm。紫外 可见漫反射光谱(UV vis)证明钇以一种六配位的形式存在。X射线光电子能谱(XPS)进一步证明钇以三价形式存在于立方介孔分子筛骨架中。 相似文献
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以十六烷基三甲基溴化铵为结构导向剂,通过水热法合成了具有立方结构的含钕Nd-MCM-48介孔分子筛材料。XRD和TEM测试表明当nNd/nSi<0.05时可以获得典型的长程有序介孔立方结构相,随nNd/nSi比的增加,晶胞参数的增大和红外吸收光谱(FT-IR)的变化为Nd进入介孔分子筛骨架中提供了有力证据。N2吸附-脱附实验给出了其BET表面积为1 195 m2·g-1,BJH平均孔径为3.6 nm。紫外-可见漫反射光谱(UV-Vis)证明钕氧形成一种八面体结构。X射线光电子能谱(XPS)进一步证明钕主要以三价形式存在于立方介孔分子筛骨架中。 相似文献
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Au nanoparticles dispersed ZrO2 thin films were prepared from two precursors HAuCl4·4H2O and ZrOCl2·8H2O in air. The structural properties and size of Au particle in ZrO2 film were characterized by X-ray diffraction (XRD) and transmission electron microscopy (TEM). The surface analysis with atomic force microscopy (AFM) showed the effect of monoethanolamine on preventing the migration of Au particles to the surface. The absorption peak of Au particles by the surface plasma resonance was observed and the red shift of absorption peak was discussed. 相似文献
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银纳米粒子的一步合成与表征 总被引:1,自引:1,他引:0
在水和乙醇溶液中,以对巯基苯胺作为还原剂,利用一步法合成了银纳米微粒,并利用拉曼光谱仪考察了对巯基苯胺在银纳米微粒表面的自组装行为.结果表明,合成的银纳米微粒的形貌与介质的pH值密切相关;对巯基苯胺可在银纳米微粒表面自组装. 相似文献
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Eduardo Larios Zulema Molina Amir Maldonado 《Journal of Dispersion Science and Technology》2013,34(5):719-723
We have synthesized copper-gold, core-shell nanoparticles by the microemulsion method. The particles were prepared in two steps, by first reducing copper ions and then gold ions in the aqueous domains of anionic microemulsions. Two surfactants have been used as emulsifiers, AOT and Cu(AOT)2. The latter is the source of copper ions. Gold ions come from aqueous solutions of HAuCl4. Ultraviolet-visible spectroscopy experiments show that copper nanoparticles are created in the first step of the synthesis, and that a gold layer covers them in the second step. Transmission electron microscopy and related techniques confirm the formation of copper (core)-gold (shell) nanocrystals. 相似文献
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Sina Safaei Farshad Asgari Moein Arzi Alireza Hojaji S. Khatiboleslam Sadrnezhaad 《Journal of Cluster Science》2017,28(3):881-889
Magnesium nanopowder has attracted many interests in the recent years, which has a very difficult and costly synthesis process because of its high activity. In this work, magnesium nanoparticles stabilized with amorphous carbon (Mg–C nanoparticles) were synthesized by submerged arc discharge technique in kerosene. The arc discharge was generated between two electrodes of magnesium at the arc current of 1 A and arc voltage of 50 V. Mg–C nanoparticles were characterized by various techniques. Dynamic light scattering result indicated that size of magnesium nanoparticles is about 35 nm. X-ray diffraction showed that the produced sample consisted of hexagonal magnesium and amorphous carbon and there was no presence of magnesium oxides in the pattern. Field emission scanning electron microscopy and transmission electron microscopy results illustrated that the sample has morphology of agglomerated nanospheres. Energy dispersive X-ray spectroscopy demonstrated formation of 57 percent magnesium and 43 percent carbon. Differential scanning calorimetry analysis showed that the amorphous carbon increased ignition temperature of nanoparticles by 180 °C compared to pure magnesium micron-sized powder. Therefore, Mg–C nanoparticles can have many applications in different fields similar to magnesium nanopowders. However, by producing Mg–C nanoparticles, there is no need for vacuum chamber or inert gases during production and after that, since amorphous carbon protects magnesium nanoparticles from oxidation. 相似文献
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Maryam Bayat Meisam Zargar Tamara Astarkhanova Elena Pakina Sergey Ladan Marina Lyashko Sergey I. Shkurkin 《Molecules (Basel, Switzerland)》2021,26(10)
In this investigation, for the first time, we used Fragaria ananassa (strawberry) leaf extract as a source of natural reducing, capping or stabilizing agents to develop an eco-friendly, cost-effective and safe process for the biosynthesis of metal-based nanoparticles including silver, copper, iron, zinc and magnesium oxide. Calcinated and non-calcinated zinc oxide nanoparticles also synthesized during a method different from our previous study. To confirm the successful formation of nanoparticles, different characterization techniques applied. UV-Vis spectroscopy, X-ray Diffraction (XRD) spectroscopy, Field Emission Scanning Electron Microscopy (FESEM) coupled with Energy Dispersive X-ray Spectroscopy (EDS), Photon Cross-Correlation Spectroscopy (PCCS) and Fourier Transformed Infrared Spectroscopy (FT-IR) were used to study the unique structure and properties of biosynthesized nanoparticles. The results show the successful formation of metal-based particles in the range of nanometer, confirmed by different characterization techniques. Finally, the presented approach has been demonstrated to be effective in the biosynthesis of metal and metal oxide nanoparticles. 相似文献
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Photochemical Synthesis of Ultrafine Cubic Boron Nitride Nanoparticles under Ambient Conditions 下载免费PDF全文
Hui Liu Peng Jin Yan‐Ming Xue Cunku Dong Xiang Li Cheng‐Chun Tang Xi‐Wen Du 《Angewandte Chemie (International ed. in English)》2015,54(24):7051-7054
Cubic boron nitride (c‐BN) is a super‐hard material whose hardness increases dramatically with decreasing size. However, c‐BN nanoparticles (NPs) with sizes less than 10 nm have never been obtained. Herein we report a simple strategy towards the synthesis of ultrafine c‐BN NPs with an average size of 3.5 nm. The method, under ambient conditions, exploits a laser‐induced photochemical effect and employs dioxane solution of ammonia borane (AB) as a liquid target. Meanwhile, total dehydrogenation of AB is realized by laser irradiation. Therefore, this approach shows great potential for the preparation of super‐hard NPs as well as controllable dehydrogenation. 相似文献
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YU Ran-bo ZHENG Ming-zhen CHEN Jun DENG Jin-xia LIU Gui-rong XING Xian-ran 《高等学校化学研究》2010,26(2):185-188
Cubic (Zn,Li)TiO3 powders were synthesized through a modified sol-gel route including the Pechini process via a three-step heat treatment.The as-synthesized (Zn,Li)TiO3 could be stable up to 1000°C.The dielectric constant and dielectric loss tangent of all the synthesized (Zn,Li)TiO3 samples at different measurement frequencies showed the similar tendency.At the same frequency,the dielectric constant and the dielectric loss tangent of (Zn,Li)TiO3 samples decreased and increased,respectively,with the lithium doping content increase.The as-prepared (Zn,Li)TiO3 showed improved microwave dielectric properties,and its maximum value of quality factor could reach 34000 GHz. 相似文献
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Surface modified silver nano particles were synthesized in a mixture solvent of water-alcohol with Pyridinium di-n-octadecyldithio phosphate(PyDDP) as a modification agent. Themorphology and structure of DDP-coated Ag (Ag-DDP) nanoparticles were characterized using X-ray powder diffraction(XRD), Transmission electron microscopy(TEM), Fourier transform infrared spectrum (FT-IR) and Thermo gravimetric analysis(TGA). Anti wear properties of Ag-DDP nano particles were tested using a four-ball tribological testing machine. The disperse properties of Ag-DDP nanoparticles were evaluated in solvents such as chloroform, benzen, toluene, liquid paraffin, distilled water and ethanol. The results show that Ag-DDP nanoparticles disperse in organic solvents, but they don’t disperse in water or ethanol. The good disperse properties in organic solvents enable Ag-DDP nanoparticles to be used as oil additives. The XRD pattern of Ag-DDP nanoparticles indicates that they have fcc crystal structure, and the modification layer can prevent the oxidation of Ag nanocores. TEM graphs show that Ag-DDP nanoparticles have a homogeneous grain distribution; the average diameter is about 15nm. FT-IR and TGA curves indicate that the existence of modification layer can prevent the adsorption of water on the surface of nanoparticles. Tribological tests show that Ag-DDP nanoparticles have good anti-wear properties in liquid paraffin, and they can improve the applied load of base oil. 相似文献
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在不引入其它还原剂和稳定剂的情况下, 加热天然生物多聚糖——壳聚糖(CHIT)和氯金酸的混合溶液, 一步反应制备高稳定性的金纳米粒子(GNPs). 采用紫外光谱、红外光谱、热重分析和透射电镜对产品进行了表征. 结果表明: 改变CHIT的浓度能够调控GNPs的光学和结构性质; 老化-时效处理可以作为粒子增长过程中的一个调控手段. 动力学数据证明GNPs的时效处理过程是一个CHIT诱导的自催化生长过程; 红外谱中1713.3 cm-1左右出现的新的吸收带, 可能是作为还原剂参加反应的壳聚糖或者它的水解产物分子中的部分羟基被氧化为羰基引起的. 本文工作也为进一步阐明目前还处于探索阶段的纳米粒子的形成机制以及实现其工业化绿色生产提供了可能性. 相似文献