O. R. Musaev

Nanoparticle fabrication of hydroxyapatite by laser ablation in water

Synthetic polycrystalline hydroxyapatite was ablated in water with 337 nm radiation from a UV nitrogen pulsed laser. According to transmission electron microscopy micrographs, the ablated particles were approximately spherical and had a size of ∼80 nm. Raman spectroscopic analysis demonstrated that particles had the same structure as the original crystal. X-ray photoelectron spectroscopy showed that the surface chemical composition was close to that of the original material. The characteristics of the ablated particles and estimations of the temperature rise of the hydroxyapatite surface under laser irradiation are consistent with the mechanism of explosive boiling being responsible for ablation. The experimental observations offer the basis for preparation of hydroxyapatite nanoparticles by laser ablation in water.

Fractal character of titania nanoparticles formed by laser ablation

Titania nanoparticles were fabricated by laser ablation of polycrystalline rutile in water at room temperature. The resulting nanoparticles were analyzed with x-ray diffraction, Raman spectroscopy, and transmission electron microscopy. The electron micrograph image of deposited nanoparticles demonstrates fractal properties.

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.