Formation of gold nanoparticles by laser ablation in aqueous solution of surfactant

Gold nanoparticles were produced by laser ablation of a gold metal plate in an aqueous solution of sodium dodecyl sulfate. The absorption spectrum of the gold nanoparticles was essentially same as that of gold nanoparticles c hemically prepared in a solution. The size distribution of the nanoparticle s thus produced was measured by an electron microscope and was found to shi ft to a smaller size with an increase in surfactant concentration. This beh avior is explained in terms of the dynamic formation model. Dependence of t he nanoparticle abundance on surfactant concentration in the solution shows that stable gold nanoparticles tend to be formed as the surfactant concent ration exceeds 10(-5) M. The gold nanoparticles having diameters larger tha n 5 nm were pulverized into those having diameters of 1-5 nm by a 532-nm la ser.