Silver colloidal nanoparticles by electrochemistry: temporal evaluation and surface plasmon resonance

Abstract

The electrochemical technique for obtaining silver nanoparticles has advantages over other methods. For the synthesis, a colloidal silver generator (Colloidal Silver Generator® model 1001) was used, where two electrodes coupled to high purity silver rods (99.99%) were used, with a potential difference of 24 V. Nanoparticle concentration was measured by total dissolved solids, using the SI-Analytic HandyLab 680 FK multiparameter in 200 mL of Milli-Q deionized water, reporting 18 ppm at 1 hour at room temperature. The determination of the resonance wavelength of the surface plasmons was carried out by finding the maximum absorbance by UV-Visible spectrophotometry with λ = 423 nm. The morphology and size of the nanoparticles was determined by Transmission Electron Microscopy, observing spherical morphology and sizes smaller than 50 nm. The chemical composition was determined by X-ray energy dispersed spectroscopy, finding a weight concentration of 93.22% of silver. The results show an optimal synthesis of colloidal silver, with characteristics that will allow the inhibition of microorganisms of interest.