Silver nanoparticles electronics applications

The electrodeposition of silver from chloroaluminate ionic liquids has been studied by several authors [45-47], Katayama et al. [48] reported that the room-temperature ionic liquid l-ethyl-3-methylimidazolium tetrafluoroborate ([EMIM]BF4) is applicable as an alternative electroplating bath for silver. The ionic liquid [EMIM]BF4 is superior to the chloroaluminate systems since the electrodeposition of silver can be performed without contamination of aluminum. Electrodeposition of silver in the ionic liquids 1-butyl-3-methylimidazolium tetrafluoroborate ([BMIM]BF4) and l-butyl-3-methylimidazoliumhexafluorophosphate was also reported [49], Recently we showed that isolated silver nanoparticles can be deposited on the surface of the ionic liquid Tbutyl-3-methylimidazolium trifluoromethylsulfonate ([BMIMJTfO) by electrochemical reduction with free electrons from low-temperature plasma [50] (see Chapter 10). This unusual reaction represents a novel electrochemical process, leading to the reproducible growth of nanoscale materials. In our experience silver is quite easy to deposit in many air- and water-stable ionic liquids. 

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]. 

Secheresse reported size-controlled formation of silver nanparticles (43) by direct bonding of ruthenium complex 42 and silver nanoparticles. Oxazole 42 was formed by the reaction of diketone 40 and aldehydes 41 under the influence of NH4OAC. These metallic nanoparticles may find applications in DNA sequencing, catalysis, optics, nanoscale electronics and antimicrocrobials. ... 

The method avoids the use of nonvolatile surfactants and polymers, which may be adsorbed onto the silver nanocubes and interfere with their possible applications in catalysis and anal3d ical devices based on SERS spectroscopy. Figure 8.9 shows the transmission electron microscopy (TEM) image of the nanocube obtained using 310 M CaC. It is evident that the nanocube is composed of smaller silver nanoparticles. The nanocubes show good SERS activity in the presence of adsorbed 4-MBA with excitation at 632.8 nm, and the enhancement factor reaches 7.610 . The nanocubes are produced in a simple and cost-effective way, and they are expected to play an important role in the development of SERS-based anal3Aical devices. The method may represent a novel route for preparation of metal nanocubes, which is a subject of intense interest. 

In recent years, research on polymer-metal nanoeomposites and their properties has attracted considerable attention due to their potential applications in catalysts, electronics and non-linear optics. Polymer-metal composites consist of polymer and metal particles on the surface or interior (core) of the polymer matrix." They exhibit various properties depending on the type of metal and polymer, especially the former. These composites not only combine the advantageous properties of polymers and metals but also exhibit many new characteristics that single-phase materials do not have. Precious metals such as silver and gold have been studied most extensively among polymer-metal nanoeomposites." Many polymer-metal nanoeomposites have been prepared in one step with y-irradiation in an aqueous solution. Choi et al. reported on polyester-silver and nylon-silver nanoeomposites prepared by the dispersion of silver nanoparticles, which were prepared by y-irradiation, on to polyester and nylon during condensation polymerization to obtain antibacterial fibers." It was found that the silver nanoparticles aggregated in the polyester matrix, whereas the silver nanoparticles dramatically dispersed in the nylon matrix. 

Surface plasmons (SPs) are collective electronic excitations near the surfaces of metallic structures. They can usually be described well with classical electromagnetic theory and correspond to electromagnetic fields that are localized and relatively intense near the metallic surfaces [1, 2]. These properties make them potentially useful for a variety of applications in optoelectronics, chemical and biological sensing, and other areas. Metallic nanostructures such as metal nanoparticles and nanostructured thin metal films, particularly those composed of noble metals such as silver or gold, are of special interest because often their SPs can be excited with visible-UV light and are relatively robust. 

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