Silver nanoparticles properties

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. 

Remarkably the position of the final plasmon peak of the alloy particles is dependent on the molar ratio of gold to silver nanoparticles. When the ratio is shifted favoring either metal, an alloy of any desired composition can be formed. This alloying phenomenon indicates that it is possible for true tuneability of the properties of a set of nanoparticles. 

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

Lu LH, Wang HS, Zhou YH, Xi SQ, Zhang HJ, Jiawen HBM, Zhao B (2002) Seed-mediated growth of large, monodisperse core-shell gold-silver nanoparticles with Ag-like optical properties. Chem Commun, pp 144-145... 

Zheng et al. [29] have compared surface properties of the assembled silver nanoparticle electrode/indium-tin oxide (AAgNP/ITO) and roughened silver electrode, using electrochemical... 

Aymonier C, Schlotterbeck U, Antonietti L et al. (2002) Hybrids of silver nanoparticles with amphiphilic hyperbranched macromolecules exhibiting antimicrobial properties. Chem Commun 3018-3019... 

Iliev, V., D. Tomova, L. Bilyarska, A. Eliyas and L. Petrov (2006). Photocatalytic properties of Ti02 modified with platinum and silver nanoparticles in the degradation of oxalic acid in aqueous solution. Applied Catalysis B-Environmental, 63(3 4), 266-271. 

Setua, R, Chakraborty, A., Seth, D., Bhatta, M.U., Satyam, P.V., and Sarkar, N. 2007. Synthesis, optical properties, and surface enhanced Raman scattering of silver nanoparticles in nonaqueous methanol reverse micelles. Journal of Physical Chemistry C, 111 3901. 

The use of antimicrobial additives has been mentioned in section 12.7.2, but another route has also been investigated, the deposition of silver nanoparticles, under formaldehyde-radio frequency plasma conditions, onto food-grade silicone rubber. The bacteriocidal properties of the silver-coated surfaces were investigated by exposing them to Listeria monocytogenes, with no bacteria being detected after exposure times of 12 to 18 hours. 

Yang, Y., Matsubara, S., Xiong, L., Hayakawa, T. and Nogami, M. (2007). Solvothermal synthesis of multiple shapes of silver nanoparticles and their SERS properties. J. Phys. Chem. C 111 9095-9104. 

Metal nanoparticles have attracted considerable interest due to their properties and applications related to size effects, which can be appropriately studied in the framework of nanophotonics [1]. Metal nanoparticles such as silver, gold and copper can scatter light elastically with remarkable efficiency because of a collective resonance of the conduction electrons in the metal (i.e., the Dipole Plasmon Resonance or Localized Surface Plasmon Resonance). Plasmonics is quickly becoming a dominant science-based technology for the twenty-first century, with enormous potential in the fields of optical computing, novel optical devices, and more recently, biological and medical research [2]. In particular, silver nanoparticles have attracted particular interest due to their applications in fluorescence enhancement [3-5]. 

Physical and chemical properties of highly dispersed substances, including nanoparticles, are determined mainly by size effects. A shape and size of metal cores of the biocomposites have been evaluated by transmission electron microscopy (TEM). The metal nanoparticles look as uniform globules (Fig. 1). Average diameter for silver nanoparticles is 10.3 nm. They have monomodal narrow size distribution [6]. Avarage sizes for the other metal particles are the following Au - 7.7 nm, Pt - 4.5 nm, Pd - 9.7 nm. 

Figure 3 compiles selected results obtained for optical limiting properties of materials containing gold or silver nanoparticles. Note that the ordinate axis shows the normalized transmission - that is, the transmission normalized to unity at low input fluence - and not the absolute one. All kinds of materials roughly present the... 

Hilger A, Cuppers N, Tenfelde M, Kreibig U (2000) Surface and interface effects in the optical properties of silver nanoparticles. Eur Phys J D 10 115-118... 

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