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Three different samples of silver colloidal nanoparticles were synthesized via the chemical reduction method using three different stabilizers (citrate, PVP, SDS). The prepared samples were characterized using UV-vis spectra, TEM imaging and XRD analysis. Our results show that absorption spectra of the three samples were stable over time. Slight changes have occurred in the spectrum of the PVP sample, indicating lesser stability of this sample. TEM images show that silver nanoparticles are well dispersed in the three samples and the sizes of these nanoparticles range from 10:1±4:2 nm to 13:5±4:7 nm. XRD curves show that the prepared silver nanoparticles are of FCC crystal structure. The XRD curves were used to calculate the size of our nanocrystals and it is found that the average size of the nanoparticles in the citrate sample is 19.9 nm, in the PVP sample it is 11.5 nm, and in the SDS sample it is 12.5 nm. In conclusion, the prepared samples were stable over time and no considerable aggregation was observed. [ABSTRACT FROM AUTHOR]

Silver colloidal nanoparticles were prepared according to the chemical reduction method in which the ascorbic acid was used as a reducing agent and sodium citrate as a stabilizing agent. The absorption spectra of all prepared samples obtained using the UV-Vis spectrophotometer showed a surface plasmon peak at a wavelength of about 420 nm. The size of the silver nanoparticles was controlled by changing the pH values of the reaction system. At high pH, smaller size silver nanoparticles were obtained compared to low pH values. This difference can be attributed to the difference in the reduction rate of the precursor. In addition to the inverse proportionality between the size and the pH value it is clear that increasing the pH value enables us to obtain spherical nanoparticles while at low pH, rods and triangular particle shapes were formed. Poor balance between nucleation and growth processes could be the cause of this result. [ABSTRACT FROM AUTHOR]