Optical extinction to determine a size distribution of gold nanoparticles fabricated by ultrashort pulsed laser ablation

G. A. TORCHIA; L. SCAFFARDI; P. MORENO; C. MÉNDEZ; L. ROSO; J. O.TOCHO

Tenerife, España

Conferencia; 9th International Conference on Laser Ablation (COLA 2007); 2007

This work presents a method based on measurement of optical extinction spectra to determine the size of spherical gold nanoparticles suspended in solution, produced by using femtosecond laser ablation in deionized water process. The gold nanoparticles were fabricated using a fluence of »1000 J/cm2. By using an improved theoretical model that modifies in term of size the contribution of the free electrons to the dielectric function, it is possible to fit the whole experimental extinction spectrum by a calculated curve considering a particles size distribution. Complementary, in order to verify the particles size distributions, TEM was performed. The results obtained showed that the predominated nanoparticles size ranges from 1 nm to 11 nm radii. Optical extinction measurement together an appropriate theoretical model  represent an efficient, simple, low cost, fast and easier method to describe a broad size distribution of spherical gold nanoparticles independent of the way of the fabrication process.