ИССЛЕДОВАНИЕ КОЛЛОИДНЫХ РАСТВОРОВ НАНОЧАСТИЦ, ПОЛУЧЕННЫХ ПРИ ЛАЗЕРНОЙ АБЛЯЦИИ ТВЕРДЫХ ТЕЛ В ЖИДКОСТИ

The results of studies of obtaining nanoparticles in laser ablation of solids in liquids are presented, an experimental facility for obtaining nanoparticles has been developed. The facility uses a ytterbium pulse fiber laser YLP (Russia) with a radiation wavelength of 1064 nm, a pulse duration of 100 ns, a separate radiation power control unit (up to 20 W) and pulse repetition rate (20 – 60 kHz), as well as an automated target transfer system based on the motorized biaxial linear translator 8MTF (Lithuania) and controller CNC USB TB6560 (China), allowing uniform evaporation of the material from the target surface, reducing the size changes of the formed craters, thereby increasing effect the ablation efficiency with prolonged irradiation and the narrowing of the scatter in the sizes of the nanoparticles obtained. The scanning parameters are set and controlled via the computer, the scanning process is displayed on the monitor. The particle size was studied on a laser particle size analyzer SALD-7500nano (Japan). The obtained materials were studied by scanning electron microscopy, energy dispersive X-ray spectroscopy using a scanning electron microscope JCM-6000 (Japan). The facility allows produce colloidal solutions of nanoparticles, for example Ag and Si in ethyl alcohol (C 2 H 5 OH) with an average size of 45 and 33 nm, respectively, to be obtained by laser ablation of volumetric metal and semiconductor targets in liquid, respectively, and the resulting solution of coagulated Si particles was dispersed in an ultrasonic bath. To study the optical properties of the obtained colloidal solutions of Ag and Si, a spectrophotometer SF-56 (Russia) and quartz cuvettes with an optical path length of 10 mm was used, ethanol was used as a comparison. For a solution of silver nanoparticles, a minimum of light transmission at a wavelength of 390 nm is observed, this is due to the absorption of radiation at this wavelength as a result of surface plasmon resonance. A solution of silicon nanoparticles transmits radiation starting at a wavelength of more than 300 nm, and is almost completely (up to 95% in the 600 – 1100 nm region) transparent in the visible red and infrared regions of the spectrum.