Preparation of silver nanoparticles by laser ablation in water

Abstract

Solutions of silver nanoparticles are obtained by laser ablation in order to analyze the effectivity of this method. The laser used was a Nd:YAG with 1064 nm of wavelength. Characterization of these particles was done using a tranmission electron microscope and a spectrophotometer of double beam, in order to measure both the size and the absorption spectrum of these nanoparticles. The average diameter of the produced nanoparticles increases, from 9 to 22 nm, as the laser pulse energy increases from 9 to 13 mJ. These particles obtained in solution present a strong absorption due to plasmon resonance around 400 nm. It is observed that the peak absorbance of each sample is directly related with the concentration and the size of silver nanoparticles. The position and the maximum value of the peak absorbance variates when ablation time, energy density or laser energy are changed. Ablation efficiency is reduced as time progresses during the process due to the absorption and dispersion of laser light by the nanoparticle solution.