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In this paper, we report a novel preparation of indium nanoparticles by the reduction of indium chloride in ionic liquid by methanolic solution of NaBH4. The particles are characterized by means of transmission electron microscopy (TEM), X-ray diffraction and UV-visible studies indicated that the powder consist of the cubic phase of indium. The particle size of indium nanoparticles is in the range of 20 nm mean diameter by Transmission electron microscopy (TEM). The samples display a strong surface plasma absorption band at 231 nm, which indicates that the sample is metal indium and the particle size is less than 20 nm. The thermal analysis of the sample indicate indium not indium oxide. Electrochemical studies show that indium nanoparticles have very good electrical properties. 相似文献
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Ohzono T Monobe H Fukuda N Fujiwara M Shimizu Y 《Small (Weinheim an der Bergstrasse, Germany)》2011,7(4):506-513
The ability to control metal patterns at the micro- and nanoscales, along with the development of a simple fabrication method, is important to many applications in the fields of materials science, biological sensing, electronics, and photonics. Herein, a simple approach to fabricating gold micropatterns with controlled roughness is reported. In this approach, gold is evaporated onto a striped liquid micropattern formed on self-organized microwrinkles. Gold nanoribbons with higher roughness form on the liquid part of the substrate because the deposited gold atoms can diffuse, grow, and aggregate at the liquid-air interface, whereas flat gold films form on the solid part. The rough gold nanoribbons formed on the liquid can then be peeled off through contact with water. The extinction spectrum of the rough gold nanoribbons suggests characteristic surface-plasmon absorption. This shows the possibility of using rough gold nanoribbons with controlled shape in plasmonic technology. 相似文献
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Jolly Pal 《Journal of Experimental Nanoscience》2014,9(5):432-443
In this work, gold nanoparticles (AuNPs) were prepared by the microwave irradiation method and comparative studies on the removal of dye by adsorption on activated carbon (AC) and polyvinylpyrrolidone (PVP)-supported AuNPs-coated AC were made. The uniform and stable AuNPs were prepared by the reduction of gold chloride (HAuCl4) using glucose as reducing agent and PVP as a stabilising and capping agent. The resulting AuNPs were characterised by transmission electron microscopy (TEM) and UV-Vis spectroscopy. The TEM technique showed the presence of AuNPs with an average size of 20?nm. The effect of various process parameters has been investigated by following the column adsorption technique at room temperature. Percentage removal of dye increased with the decrease in initial concentration and increased with the increase in contact time. Adsorption data were modelled with the Freundlich isotherms. The Freundlich isotherm model has been applied to the equilibrium adsorption data. Desorption studies were made to elucidate recovery of the adsorbate and adsorbent for the economic competitiveness of the removal system. The adsorption capacity of the water-desorbed adsorbate reduced from 97% to 60% for n?=?6 cycles. 相似文献
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Madhuri Mandal Subrata Kundu Sujit Kumar Ghosh Tarasankar Pal 《Bulletin of Materials Science》2002,25(6):509-511
Gold nanoparticles of different sizes and shapes have been prepared by UV-photoactivation technique using the micelle TX-100
(poly(oxyethylene)iso-octylphenyl ether) as reducing agent, stabilizing agent as well as template which has been authenticated from the plasmon
absorption band and TEM picture. The heating effect on those gold nanoparticles has also been studied. 相似文献
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Firestone MA Dietz ML Seifert S Trasobares S Miller DJ Zaluzec NJ 《Small (Weinheim an der Bergstrasse, Germany)》2005,1(7):754-760
Photochemical reduction of tetrachloroaurate (AuCl4-) ions in the highly constrained aqueous domains of a nanostructured ionogel template, formed via self-assembly of the ionic liquid 1-decyl-3-methylimidazolium chloride (C10mim+Cl-) in water, results in the formation of anisotropic gold nanoparticles with a variety of sizes and morphologies, which include previously unattainable trigonal prismatic nanorods. Unexpectedly, small-angle X-ray scattering studies of the Au-ionogel composite reveal that the in situ formation of the nanoparticles increases the mesoscopic order of the ionogel, which results in its conversion to a near-monodomain structure. The findings demonstrate that nanostructured, ionic liquid-based gels can be used to template the formation of new nanoparticle morphologies with technologically important optical, electronic, and catalytic properties. It may also be possible to design soft templates that permit the fabrication of highly ordered nanoparticle array-hydrogel composites, thereby enabling control and tuning of the collective properties of the encapsulated nanoparticles. 相似文献
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Facial synthesis of polypyrrole/silver nanocomposites at the water/ionic liquid interface and their electrochemical properties 总被引:1,自引:0,他引:1
Polpyrrole (PPy)/silver nanocomposites with their size of around 80-120 nm were successfully synthesized at the interface of water and ionic liquid. High dispersed PPy/silver nanocomposites were obtained in the presence of polyvinylpyrrolidone (PVP) by controlling the reacting conditions. The morphology and structure of the resulting nanocomposites were characterized by transmission electron microscopy, Fourier transform infrared spectroscopy, X-ray diffraction and X-ray photoelectron spectroscopy. It was also found that the electrical conductivity of PPy/silver nanocomposites was much higher than that of pure PPy. Cyclic voltammetric experiments further indicated that the nanocomposite had excellent redox ability: polypyrrole; silver; ionic liquid; interface synthesis; and nanocomposites. 相似文献
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Flower-like ZnO morphology, with different shapes, have been successfully synthesized via a novel and environment-friendly hydrothermal method using zinc acetate and a task specific dicationic dibasic ionic liquid, [mmpim]2[OH]2, which plays an important role in fabrication of ZnO structure. The structure and morphology of the product were characterized by X-ray diffraction and scanning electron microscopy, which show different flower-like morphologies. Photoluminescence spectrum of the product exhibits a strong ultraviolet emission at 391 nm and two weak blue-green emissions at about 450 and 500 nm. 相似文献
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Sheng Peng Youngmin Lee Chao Wang Hongfeng Yin Sheng Dai Shouheng Sun 《Nano Research》2008,1(3):229-234
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 相似文献
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W. D. Drotning 《International Journal of Thermophysics》1985,6(6):705-714
In this study, the thermal expansion of a number of mixed oxide glasses was measured in the solid and liquid regions by gamma densitometry. Conventional density measurement techniques are limited to either the solid or the liquid phase; however, with this noncontacting technique, the density and thermal expansion of both the solid and the liquid phases may be investigated as the temperature is varied and the glass viscosity varies over a wide range. This technique allows the continuous measurement of density as the liquid cools to a supercooled glass or to a crystalline solid. Lead borate glasses were examined in the range 27 to 42 mol % PbO. The liquid-phase volumetric thermal expansion coefficient was observed to decrease with increasing PbO content, in contrast to the solid-phase linear thermal expansion coefficients. In soda-baria phosphate glasses (50 mol% P2O5), liquid-phase volumetric expansion coefficients were found to vary as the solid-phase linear expansion coefficients. Measurements on a lithia-aluminoscilicate glass ceramic were obtained by this method to approximately 400°C above the limit of conventional dilatometry. The gamma densitometry technique can yield density, thermal expansion, glass transition and crystallization information, and quenching-rate dependence data on glasses to temperatures in excess of 1500°C, and thus provides a means for high-temperature characterization of glasses which complements conventional dilatometry, calorimetry, and thermal analysis.Paper presented at the Ninth Symposium on Thermophysical Properties, June 24–27, 1985, Boulder, Colorado, U.S.A. 相似文献
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Pure and high-crystalline copper nanoparticles were synthesized at room temperature by reduction of copper nitrate with hydrazine hydrate in cetyltrimethyl ammonium bromide (CTAB) solution without using any extra gases. A parametric study has been carried out in terms of hydrazine concentration, solution pH, and stirring. Pure copper nanoparticles without oxidation were obtained at 0.1–0.2 M N2H4 and pH = 10. The growth mechanism of various shaped copper nanoparticles is discussed based on structural analysis by transmission electron microscopy and selected area electron diffraction. 相似文献
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Junbo LI Jianlong ZHAO Wenlan WU Ju LIANG Jinwu GUO Huiyun ZHOU Lijuan LIANG 《材料科学前沿(英文版)》2016,10(2):178-186
In this paper, double hydrophilic ionic liquid block copolymers (ILBCs), poly poly[1-methyl-3-(2-methacryloyloxy propylimidazolium bromine)]-block-(N-isopropylacrylamide) (PMMPImB-b-PNIPAAm) was first synthesized by reversible addition-fragmentation chain transfer (RAFT) and then attached on the surface of gold nanoparticles (Au NPs) via a strong gold-sulfur bonding for preparing hybrid nanoparticles (PMMPImB-b-PNIPAAm-@-Au NPs). The hybrid NPs had a three layers micelle-like structure, including a gold core, thermo-responsive inner shell and anion responsive outer corona. The self-assembling behavior of thermal- and anion-response from shell and corona were respectively investigated by change of temperature and addition of (CF3SO2)2N-. The results showed the hybrid NPs retained a stable dispersion beyond the lower critical solution temperature (LCST) because of the space or electrostatic protecting by outer PMMPImB. However, with increasing concentration of (CF3SO2)2N-, the micellization of self-assembling PMMPImB-b-PNIPAAm-@-Au NPs was induced to form micellar structure containing the core with hydrophobic PMMPImB-(CF3SO2)2N- surrounded by composite shell of Au NPs-PNIPAAm via the anion-responsive properties of ILBCs. These results indicated that the block copolymers protected plasmonic nanoparticles remain self-assembling properties of block copolymers when phase transition from outer corona polymer. 相似文献
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提出了一种制备ZnO纳米颗粒的新方法。在金属钠的液氨溶液中还原硝酸锌,所形成的金属Zn自然氧化而制得ZnO颗粒。为了研究表面修饰对产物形貌、粒径和性能的影响,制备了十二烷基磺酸钠(SDS)修饰的ZnO纳米颗粒。采用X射线粉末衍射仪(XRD)、透射电子显微镜(TEM)、傅立叶变换红外光谱仪(FT-IR)、热重及差热分析仪(TG-DTA)等手段对产物进行了表征。结果表明采用该方法可制得具有六方纤锌矿结构的ZnO颗粒,未修饰ZnO颗粒团聚较为严重;修饰的ZnO纳米颗粒呈棒状,分散较好。红外和热分析表明SDS修饰在了ZnO纳米颗粒表面。测试了所制备ZnO颗粒的紫外可见吸收(UV-Vis)和光致发光(PL)谱,均出现了ZnO的特征谱带。提出的方法也适用于制备其它金属或氧化物纳米材料。 相似文献
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Haajira Beevi Habeeb Rahuman Ranjithkumar Dhandapani Santhoshini Narayanan Velmurugan Palanivel Ragul Paramasivam Ramalakshmi Subbarayalu Sathiamoorthi Thangavelu Saravanan Muthupandian 《IET nanobiotechnology / IET》2022,16(4):115
The alarming effect of antibiotic resistance prompted the search for alternative medicine to resolve the microbial resistance conflict. Over the last two decades, scientists have become increasingly interested in metallic nanoparticles to discover their new dimensions. Green nano synthesis is a rapidly expanding field of interest in nanotechnology due to its feasibility, low toxicity, eco‐friendly nature, and long‐term viability. Some plants have long been used in medicine because they contain a variety of bioactive compounds. Silver has long been known for its antibacterial properties. Silver nanoparticles have taken a special place among other metal nanoparticles. Silver nanotechnology has a big impact on medical applications like bio‐coating, novel antimicrobial agents, and drug delivery systems. This review aims to provide a comprehensive understanding of the pharmaceutical qualities of medicinal plants, as well as a convenient guideline for plant‐based silver nanoparticles and their antimicrobial activity. 相似文献
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Djamila Achouri Michelle Sergent Alain Tonetto Philippe Piccerelle Virginie Hornebecq 《Drug development and industrial pharmacy》2015,41(3):493-501
In the field of keratoconus treatment, a lipid-based liquid crystal nanoparticles system has been developed to improve the preocular retention and ocular bioavailability of riboflavin, a water-soluble drug. The formulation of this ophthalmic drug delivery system was optimized by a simplex lattice experimental design. The delivery system is composed of three main components that are mono acyl glycerol (monoolein), poloxamer 407 and water and two secondary components that are riboflavin and glycerol (added to adjust the osmotic pressure). The amounts of these three main components were selected as the factors to systematically optimize the dependent variables that are the encapsulation efficiency and the particle size. In this way, 12 formulas describing experimental domain of interest were prepared. Results obtained using small angle X-rays scattering (SAXS) and cryo-transmission electron microscopy (cryo-TEM) evidenced the presence of nano-objects with either sponge or hexagonal inverted structure. In the zone of interest, the percentage of each component was determined to obtain both high encapsulation efficiency and small size of particles. Two optimized formulations were found: F7 and F1. They are very close in the ternary phase diagram as they contain 6.83% of poloxamer 407; 44.18% and 42.03% of monoolein; 46.29% and 48.44% of water for F7 and F11, respectively. These formulations displayed a good compromise between inputs and outputs investigated. 相似文献