An affordable technique for nitrogen-carbon nanoparticle synthesis: Dense medium plasma and statistical analysis of the production affecting factors

Within the scope of the thesis, the process factors (parameters) affecting the production process with liquid phase dense medium plasma technology (dense medium plasma), which a limited number of researchers worked on, were determined and carbon-based nanoparticles were produced. The properties acquired by nanoparticles vary according to their size. Since these dimensions vary according to the application area to be used, it is important to be able to choose levels according to the application area. The effect of these factors affecting the production process created by using dense medium plasma technology on nanoparticle size, which is the critical quality feature of nanoparticles, was investigated using statistical experimental design. In the thesis study, statistical analyzes were carried out using full factorial experimental design, which is one of the experimental design methods. In order to optimize factor values, four factors were specified, two levels for each factor were determined, and 24 full factorial experimental design method was used. With the aim of achieving controlled nanoparticle size production, time, distance between electrodes, flow velocity and amine were chosen as four factors that can affect this production. The lower and upper levels of the factors time 45 seconds- 90 seconds, distance between electrodes 2 milimeters- 5 milimeters, flow rate 3 liters/ minute- 6 liters/ minute, amine 0.5 mililiter- 2 mililiters. Scanning electron microscopy analysis was used for morphological and surface analysis of nanoparticles, energy dispersion spectrometer (EDX) and electron spectroscopy for chemical analysis (ESCA) was used to perform elemental analysis. Nanoparticle sizes were measured in pixels with Image J program, and this pixel measurement length was converted to nano value, the size distribution was obtained from these values and analyzed by statistical analysis in Minitab 19 program. As a result of this study, time, distance between electrodes, flow velocity and amine factors were found to be significant, besides being significant in double and triple interactions, interactions between some factors were found to be insignificant.