Effect of electric fields on tin nanoparticles prepared by laser ablation in water

A pulsed laser beam from an excimer laser was used to ablate a solid tin target immersed in water in the presence of an external electric field. High fluence resulted in the formation of an overheated melt at the target surface resulting in homogeneous nucleation and phase explosion. The ablation products were studied with transmission electron microscopy. It was found that with no external field the size distribution of particles has peaks at ∼1 and ∼10 nm and that externally applied electric fields resulted in a decrease of particle size. A model based on Rayleigh instability and polarization effects was proposed to explain the observations. This work demonstrates a possible approach for controlling nanoparticle size.