Eco-friendly synthesis of ZnO nanoparticles using Siirt pistachio thin shell extract: promising applications in photocatalysis and antibacterial solutions.

Green synthesis has gained considerable attention as a sustainable and environmentally friendly approach to nanomaterial fabrication. In this study, zinc oxide (ZnO) nanoparticles (NPs) were synthesized using an aqueous extract of Siirt pistachio thin shells, which acted as a natural reducing, stabilizing, and capping agent due to its rich phytochemical content. This green route eliminates the use of toxic chemicals, offering a cost-effective and scalable alternative for nanoparticle production. The synthesized ZnO NPs were characterized by SEM, TEM, XRD, EDX, and FTIR analyses, revealing predominantly spherical morphology with an average crystallite size of approximately 20 nm calculated by the Debye-Scherrer equation. Photocatalytic activity was assessed through methylene blue (MB) dye degradation under visible light, following a pseudo-first-order kinetic model with a rate constant of 0.0462 min^-1, while antibacterial performance was evaluated via disk diffusion, showing significant inhibition zones against various pathogenic bacteria. The results demonstrate that the ZnO NPs exhibit excellent photocatalytic and antimicrobial properties, highlighting the potential of this green synthesis method for wide-ranging applications in environmental remediation, antimicrobial surface coatings, food packaging, cosmetics, and biomedical technologies.