Preparation of silicon and aluminum nanoparticles in an aqueous solution

Abstract

The interest in nanomaterials is due to a significant change in their physical properties compared to massive materials. Changes in the physical and chemical properties of particles containing several hundred or thousands of atoms are determined by changes in the density of electronic states.Aqueous solutions of aluminum and silicon nanoparticles were obtained by laser ablation. Pulsed laser treatment was performed in the mode of double pulses in distilled water. The invested energy was: for aluminum 1000–1500 J, the exposure time is 10–25 min., for silicon-50–1000 J with exposure times from 1 to 10 min.The features of the morphology of the obtained particles, as well as the surface of polycrystalline aluminum and silicon craters, were determined by scanning electron microscopy. It is shown that an ensemble of particles of different sizes from 20 nm to 2.0 microns is formed. Some aluminum particles are cut, which allows us to talk about their cristallinity. It is shown that the structure of the target surface after laser exposure consists of grains separated from each other by thermal etching grooves, since the evaporation of the material occurs primarily along the grain boundaries.

Keywords

• nanoparticles
• laser ablation
• aluminum
• silicon
• two-pulse laser mode