Laser-Based Formation and Properties of Gold Nanoparticles in Aqueous Solution: Formation Kinetics and Surfactant-Modified Particle Size Distributions

We report on the time evolution of gold nanoparticle (AuNP) optical properties and size distributions as a function of laser irradiation in pure water samples and at sodium dodecylsulphate (SDS) surfactant concentrations above and below the SDS critical micelle concentration in water. Our investigations provide a mechanistic insight into the laser-induced formation kinetics involved in AuNP production via 1064 nm laser irradiation in aqueous solution, as well as the relative stabilities of different AuNP size regimes. Following preparation via laser ablation at 1064 nm, we show that 532 nm laser irradiation in the absence of surfactant generates AuNP that are both small in size and possess a narrow particle size distribution. This distribution remains narrow and shifts to smaller average particle size with increasing surfactant concentration.