Silver nanoparticles preparation

Figure 4. TEM photograph of silver nanoparticles prepared by the thermolysis of Ci3H27C02Ag (reprinted from Ref. [18], 2006, with permission from Elsevier).

Fig. 6.2 Absorption spectrum of silver nanoparticles prepared from an aqueous solution (70 ml) of AgN03 (0.2 mM) containing polyethylene glycol (0.1 wt%) and ethylene glycol (0.1 M)...

Fig. 18.1 TEM image (the scale bar is 50 nm) and histogram of silver nanoparticles prepared by the electrochemical method (adapted with permission from [14]...

Silver Nanoparticles Preparation. A colloidal suspension of citrate reduced silver nanoparticles was prepared using a modified Lee and Meisel [8] procedure. 

High enhancement of the copper localized surface plasmon absorbency was recorded at the two-layer planar system consisted of copper and silver nanoparticles prepared with successive vacuum evaporation. The result obtained may be caused by strong near-field coupling in the close-packed binary system. The effect may be used for the development of high-absorptive coatings and spectral selective nanoelements in the visible and near infrared spectral ranges. 

R. M. Tilaki,A. Irajizad, S. M. Mahdavi Stability, Size and Optical Properties of Silver Nanoparticles Prepared by Laser Ablation in Different Carrier Media, Appl. Phys. A. 2006, v. 4,215-219. 

Vasilkov, A., Naumkin, A., Nikitin, L. Volkov, L, Podshibikhin, V, and Lisichkm, G. Ul-trahigh molecular weight polyethylene modified with silver nanoparticles prepared by metal-vapour synthesis. AIP Conference Proceedings., 1042,255-257 (2008). 

How are silver nanoparticles prepared in a vegetable oil-based polymer... 

Marsich, E., et al., 2013. Nano-composite scaffolds for bone tissue engineering containing silver nanoparticles preparation, characterization and biological properties. Journal of Materials Science. Materials in Medicine 24 (7), 1799-1807. Available at http //www. ncbi.nlm.nih.gov/pubmed/23553569 (accessed 10.10.14.). 

Another report which involves the use of PVP describes the comparison of silver nanoparticles prepared by y-radiation and by chemical reduction [31]. It was reported that the y-radiation strategy produced silver nanoparticles with a narrower size distribution, with the final size also being tuned by varying the concentration of the silver nitrate precursor. In contrast, the chemical reduction method does not allow such ease in tuning the particle size. 

Figure 3.S (a) Assembly of spherical silver nanoparticles prepared by the microemulsion method on HOPG (b) Sample after annealing at 50°C at atmospheric pressure for 8 days. Adapted with permission from Ref [45] 2007 MacMillan Publishers Ltd.

Let us come back to the sample preparation A drop of solution containing silver nanoparticles dispersed in hexane is deposited on the substrate. The nanocrystals can be removed by washing the substrate and collected in hexane. The absorption spectrum of silver particles recorded before and after deposition remains the same. This indicates that coalescence does not take place. Similar behavior was observed by using HOPG as a substrate [6,35]. 

Competitive reduction of Au(III) and Ag(I) ions occurs simultaneously in solution during exposure to neem leaf extract leads to the preparation of bimetallic Au-core/Ag-shell nanoparticles in solution. TEM revealed that the silver nanoparticles are adsorbed onto the gold nanoparticles, forming a core/sheU structure. Panigrahi et al. [121] reported that sugar-assisted stable Au-core/Ag-shell nanoparticles with particles size of ca. 10 nm were prepared by a wet chemical method. Fructose was found to be the best suited sugar for the preparation of smallest particles. 

In Section 2 the general features of the electronic structure of supported metal nanoparticles are reviewed from both experimental and theoretical point of view. Section 3 gives an introduction to sample preparation. In Section 4 the size-dependent electronic properties of silver nanoparticles are presented as an illustrative example, while in Section 5 correlation is sought between the electronic structure and the catalytic properties of gold nanoparticles, with special emphasis on substrate-related issues. 

Stearate-stabilized silver nanoparticles, C17AgNP, were prepared by the simple one-pot thermolysis of silver stearate, C17COOAg. The powder of C17COOAg (1.0 mmol) was placed in the bottom of three necked flask, and then heated up to 250 °C to afford a liquid. Heating the liquid... 

Table 5. Properties of silver nanoparticles C17AgNP prepared by the controlled thermolysis of C17COOAg.

Jiang LP, Wang AN, Zhao Y et al (2004) A novel route for the preparation of monodisperse silver nanoparticles via a pulsed sonoelectrochemical technique. Inorg Chem Commun 7 506-509... 

Fig. 6.2). TEM observations for the as-prepared, silver nanoparticles showed that the nanoparticles of silver were ca.15 nm in size (Fig. 6.3). 

Salkar RA, Jeevanandam P, Aruna ST, Yuri K, Gedanken A (1999) The sonochemical preparation of silver nanoparticles. J Mater Chem 9 1333-1335... 

Alqudami, A. and Annapoorni, S. (2007) Fluorescence from metallic silver and iron nanoparticles prepared by exploding wire technique. Plasmonics, 2, 5-13. 

In a more simple and cheap way, silver clusters can be prepared in aqueous solutions of commercially available polyelectrolytes, such as poly(methacrylic acid) (PM A A) by photo activation using visible light [20] or UV light [29]. Ras et al. found that photoactivation with visible light results in fluorescent silver cluster solutions without any noticeable silver nanoparticle impurities, as seen in electron microscopy and from the absence of plasmon absorption bands near 400 nm (F = 5-6%). It was seen that using PMAA in its acidic form, different ratios Ag+ MAA (0.15 1-3 1) lead to different emission bands, as discussed in the next section (Fig. 12) [20]. When solutions of PMAA in its sodium form and silver salt were reduced with UV light (365 nm, 8 W), silver nanoclusters were obtained with emission band centered at 620 nm and [Pg.322]

Yu, A., et al., Silver nanoparticle-carbon nanotube hybrid films Preparation and electrochemical sensing. Electrochimica Acta, 2012. 74(0) p. 111-116. 

Li et al. reported first on the decoration of hydrothermal carbon spheres obtained from glucose with noble metal nanoparticles [19]. They used the reactivity of as-prepared carbon microspheres to load silver and palladium nanoparticles onto then-surfaces, both via surface binding and room-temperature surface reduction. Furthermore, it was also demonstrated that these carbon spheres can encapsulate nanoparticles in their cores with retention of the surface functional groups. Nanoparticles of gold and silver could be encapsulated deep in the carbon by in situ hydrothermal reduction of noble-metal ions with glucose (the Tollens reaction), or by using silver nanoparticles as nuclei for subsequent formation of carbon spheres. Some TEM images of such hybrid materials are shown in Fig. 7.4. 

Lochner, N., Wirth, M., Pittner, F., Gabor, F., Preparation, characterization and application of artificial Caco-2 cell surfaces in the silver nanoparticle enhanced fluorescence technique. J Control Release 89, 249-259 (2003). 

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