Stability and optical properties of gold nanoparticles in different liquids produced by laser ablation
|Reza M. Tilaki , Azam Iraji zad , Seyed Mohammad Mahdavi , Mehdi Ranjbar|
Sharif University of Technology, Azadi Avenue, Tehran 14588, Iran
We study the preparation, stability and optical properties of pure gold nanoparticles prepared by pulsed laser ablation from gold target in water and ethanol as liquid carrier media. Nd:YAG laser at wavelength of 1064 nm, 130 mJ/pulse energy, 10 ns duration and reparation rate of 10 Hz has been used for ablation. Optical properties and structures of nanoparticles were investigated by UV/visible and TEM. The shapes of particles are rather spherical in all of the carrier media. Gold nanoparticles in water are stable and exhibit narrow size distribution with mean diameter of about 7 nm. But in ethanol broad size distribution with mean diameter of 18 nm was observed. Some of nanoparticles gathered to form chain like structures. Gold nanoparticles in ethanol completely precipitated after 2 days. Optical extinction spectrum of nano gold in water is sharp with single maximum at 522 nm, whereas in ethanol a red shift with broadening in spectra has been observed. In addition a rather weak peak at 545 nm was appeared which is related to surface plasmon resonance.In present paper we discussed size and stability of nanoparticles by considering the polarity of different media. This study provides a simple method for synthesis and control the properties of gold nanoparticles produced by laser ablation method.
Presentation: Oral at E-MRS Fall Meeting 2006, Symposium D, by Reza M. Tilaki
See On-line Journal of E-MRS Fall Meeting 2006
Submitted: 2006-05-14 16:03 Revised: 2009-06-07 00:44