Non-Thermal Plasma Enhanced Highly Efficient Photocatalytic Degradation of Aspirin in Water Using ZnO Nanoparticles

The presence of pharmaceutical contaminants such as acetylsalicylic acid (aspirin) in aquatic systems poses significant risks to environmental and human health. Here, we report a synergistic treatment approach combining ZnO nanoparticle photocatalysis with non-thermal plasma (NTP) activation to achieve rapid and efficient aspirin degradation in water. ZnO nanoparticles were synthesized via the GAD plasma method and characterized by XRD, SEM, TEM, UV–Vis, and PL spectroscopy, confirming their hexagonal wurtzite structure, nanoscale morphology, and high optical activity. Photocatalytic experiments under UV irradiation achieved substantial aspirin removal, which was further enhanced when coupled with gliding arc discharge plasma treatment, reaching over 99% degradation and significant total organic carbon (TOC) reduction. The combined process exploits reactive oxygen and nitrogen species generated at the plasma liquid interface, promoting accelerated electron hole separation and radical-driven oxidation at the nano-geo interface. This work demonstrates a green, highly efficient hybrid advanced oxidation process for pharmaceutical pollutant mitigation, contributing to sustainable water remediation strategies.