Applications silver sols

Among the many applications of LB films, the creation or arrangement of colloidal particles in these films is a unique one. On one hand, colloidal particles such as 10-nm silver sols stabilized by oleic acid can be spread at the air-water interface and LB deposited to create unique optical and electrooptical properties for devices [185]. 

Since SERS and SERRS are substance specific, they are ideal for characterisation and identification of chromatographically separated compounds. SE(R)R is not, unfortunately, as generally applicable as MS or FUR, because the method requires silver sol adsorption, which is strongly analyte-dependent. SE(R)R should, moreover, be considered as a qualitative rather than a quantitative technique, because the absolute activity of the silver sol is batch dependent and the signal intensity within a TLC spot is inhomogeneously distributed. TLC-FTIR and TLC-RS are considered to be more generally applicable methods, but much less sensitive than TLC-FT-SERS FT-Raman offers p,m resolution levels, as compared to about 10p,m for FTIR. TLC-Raman has been reviewed [721],... 

Solutions of silver sols (i.e. colloidal dispersions of Ag in aqueous solution) have some application as bactericidal agents. The active agent is Ag, with the metabolism of bacteria being disrupted by its presence. A silver sol exhibits a large metal surface area, and oxidation by atmospheric O2 occurs to some extent to give Ag20. While this is only... 

Polymer adsorption is important in the flocculation and stabilization of colloidal sols and has been reviewed by Vincent et al. (1) and Tadros (2). Polyvinyl alcohol (PVA) has been used in these studies because of its practical application in textiles, adhesives, and coatings. The adsorption of PVA has been studied on silver iodide by Fleer (3) and Koopal (4), and on polystyrene (PS) latex particles by Garvey (5). The adsorption isotherms reported by these workers extend up to 600 ppm PVA. The adsorption at... 

The aim of this work is to explore the applicability of the sol-gel method for the preparation of Ag/Si02 and Cu/Si02 catalysts and to see whether such a method can yield silver and copper species stabilized by the carrier. Characterization of the catalyst structure by several physical and chemical techniques, including N2 adsorption-desorption isotherms, mercury porosimetry measurements, X-ray diffraction and transmission electron microscopy, has been used to correlate the microstructure of Ag/Si02 and Cu/Si02 catalysts with their catalytic performance. 

For the preparation of mesoporous gold containing catalysts, Somorjai demonstrated the application of preformed metal sols in combination with the neutral template hexadecyl amine . Totally carbohydrate-based approaches to starch-stabilized gold and silver nanosols by reduction with glucose were published by Paf and recently by Raveendran . 

Electrodeposited sol-gel-based composite films also showed optical applications. Gu and coworkers [85,86] co-electrodeposited Te0 > -Si02 hybrid films from the TEOS-Te(i-PrO)4 niixed precursor for nonlinear optics. Te(IV) was partially reduced during electrodeposition, as characterized by EDX of the obtained films. The as-prepared films had third-order nonlinear susceptibility ix ) of 5.9 X10 to 4.29 X 10 esu, and the films had of 1.551 X 10 esu after posttreatment annealing. Mandler and coworkers co-electrodeposited TMOS with multiwalled carbon nanotubes (MWCNTs) on ITO and silver. The optimized films electrodeposited on ITO showed transparency of about 50% with nonlinear optical properties, and the optimized films electrodeposited on silver had specular reflectance lower than 0.5% in the wavelength range of 400-15 000 nm, which can be used as antireflection coatings. 

Maduraiveeran, G., Manivasakan, P.. and Ramaraj, R. (2011) Silver nanoparticles embedded three dimensional silicate sol gel matrix modified electrode for nitrite sensor application. Int J. NanotechnoL,... 

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