Synthesis and Experiment on SERS

We attempted to estimate the SERS enhancement factor (EF) using the following equation  

Controlling the size, shape, and structure of metal nanoparticles is very important because of the strong correlation between these parameters and their resulting optical, electrical, and catal3Aic properties [65]. We reported a directed calcium chloride coalescence method, based upon incubating a silver colloid with an aqueous solution of CaCl2, for preparation of silver nanocubes with a particle size of 270 to 950 nm. 

Nickel has been known to be one of the important catalytic, magnetic, and conductive materials. A one-step facile synthesis was devised for preparation of well-dispersed AgNi coreshell nanoparticles with uniform and intact shells [66]. The process is performed by a reduction of silver nitrate and nickel nitrate with sodium borohydride in water-in-oil (W/0) microemulsions of wa-ter/polyoxyethylene (4) nonylphenol (OP-4] and polyoxyethylene [7] nonylphenol (0P-7]/n-heptane. TEM (see Fig. 8.10], X-ray diffraction (XRD], X-ray photoelectron spectroscopy (XPS], and UVvis absorption are utilized to characterize the AgNi coreshell nanoparticles. The thickness of Ni layers on the surface of Ag nanoparticles could be controlled by the dosage of Ni + and Ag+. The AgNi coreshell nanoparticles showed a high catalytic activity for degradation reaction of eosin Y (see Fig. 8.11]. The product may also 

We reported a pelletization method to prepare activity-tunable substrates [67], which is very simple. The results show that SERS activity of the metal pellet varies with the pressure used to make it. Since no chemical process is involved in the preparation of the 

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