Dye degradation, pathogen control, photocatalytic and antibacterial phenomena of green-synthesized ZnO-polypyrrole nanocomposites

The escalating pollution from textile and industrial wastewater necessitates the development of efficient methods for contaminant removal. This study investigates the catalytic and biological activities of biosynthesized zinc oxide (ZnO) nanoparticles (NPs) and their polypyrrole nanocomposites (ZnO-P). ZnO NPs were synthesized using Eucalyptus teriticornis leaf extract, while ZnO-P nanocomposites were prepared with varying polymer concentrations. The materials were characterized, and their photocatalytic efficiency was tested against Brilliant Blue and Crystal Violet dyes under sunlight. The ZnO-P composites demonstrated superior photocatalytic activity, achieving up to 97.01% degradation of dyes, attributed to enhanced charge separation and light absorption. The results confirmed that the antioxidant activity of the nanocomposites increased significantly. The antibacterial activity was also investigated, with the ZnO-PP nanocomposites showing enhanced inhibition of S. aureus and E. coli, surpassing the performance of ZnO NPs alone. The better performance is credited to the synergistic effects of Polypyrrole, which enhanced charge separation, extended light absorption, and improved interaction with bacterial membranes. These results suggest that ZnO-P nanocomposites are auspicious materials for wastewater treatment and antibacterial applications.