Study of the Characteristics and Photocatalytic Application of ZnO Nanoparticles Synthesized by Cold Plasma

This thesis explores the synthesis, characterization, and photocatalytic applications of zinc oxide nanoparticles (ZnO NPs) produced using a Gliding Arc Discharge (GAD) plasma method. The study primarily investigates the influence of discharge duration on the structural, optical, and photocatalytic properties of ZnO NPs. Characterization techniques such as X-ray diffraction (XRD), scanning electron microscopy (SEM), and UV-visible spectroscopy were employed to evaluate the physical and chemical properties of the nanoparticles. The results show that increasing from 10 min to 60 min the discharge duration leads to a decrease in particle size from 28 nm to 25 nm, higher band gap energies, and improved thermal stability. The ZnO NPs exhibited excellent photocatalytic performance in the degradation of organic pollutants, with degradation efficiencies of 92.9%, 71%, and 88% for Brilliant Cresyl Blue (BCB), Methylene Blue (MB), and Congo Red (CR) dyes, respectively, under UV light. Furthermore, under sunlight, the ZnO NPs achieved up to 97% photodegradation efficiency of CR dye after 150 minutes, with optimal performance at pH 8. The study also demonstrated the effectiveness of combining GAD plasma with ZnO NPs for aspirin degradation, achieving a 96.72% degradation efficiency within 90 minutes. These findings highlight the potential of GAD plasma-synthesized ZnO NPs for practical applications in wastewater treatment, offering a sustainable and efficient solution for organic pollutant degradation. The synthesized ZnO NPs also demonstrated stability and reusability over multiple cycles, showcasing their potential for large-scale environmental applications