Diagnostics and characterization of nanoparticles in dusty glow discharge plasma

This paper presents the results of a comprehensive experimental study of dusty plasma containing nanoparticles, with a particular focus on the correlation between the characteristics of synthesized carbon nanoparticles and the parameters of low-temperature gas discharge plasma. The effects of discharge parameters-such as pressure, applied voltage, and processing time-on electron temperature and nanoparticle formation dynamics were investigated. It was found that the electron temperature reaches its maximum value (1.3 eV) at a pressure of 1 Torr and an applied voltage of 1 kV during the initial stage of the discharge (short times). A further increase in voltage or time, or a decrease in pressure, leads to a decrease in electron temperature. Using the laser attenuation method, the time-dependent evolution of nanoparticle density and size was determined. An increase in particle diameter, from 115 to 195 nm, was observed over time, accompanied by a decrease in particle concentration, from ~ 3*10¹³ m^-3 to ~ 0.4*10¹³ m^-3, within the plasma volume. The properties of the particles synthesized during a short synthesis time in the plasma volume and at maximum electron temperatures were characterized using scanning electron microscopy for surface morphology, transmission electron microscopy for internal structure, Raman spectroscopy for structural order and defects, photoluminescence spectroscopy and UV-Vis spectrophotometry for optical properties, and X-ray photoelectron spectroscopy for chemical composition and bonding states. The nanoparticles were found to have a predominantly spherical shape and an amorphous structure. Photoluminescence in the range of 400-600 nm was also recorded, attributed to the size effect and the presence of surface defects. The results provide deeper insight into the relationship between plasma parameters and the resulting properties of synthesized nanomaterials, offering valuable prospects for the controlled synthesis of nanoparticles in applied nanotechnology.