Mössbauer study of iron oxide nanoparticles produced by laser ablation of metallic iron in water and effects of subsequent laser irradiation

Abstract

Laser ablation of a metallic iron block in a flow of water was performed to produce both iron and iron oxide nanoparticles. The X-ray diffraction patterns and Mössbauer spectra for the particles indicated that the resulting material consisted of α-Fe and Fe_0.89O nanoparticles. Transmission microscopy images demonstrated that these particles were spherical with diameters in the range of 5 to 45 nm with an average size of 20 nm. The particles were re-suspended in water and irradiated with laser light, following which the particle size was decreased and the material was further oxidized to amorphous Fe₂O₃. These results establish that laser ablation and laser irradiation have different effects when processing iron and iron oxide particles.