Aesculus hippocastanum extract-mediated biosynthesis of silver-decorated zinc oxide nanoparticles and investigation of their photocatalytic, antibacterial, and antioxidant properties

In this research, silver-decorated zinc oxide nanoparticles (ZnO–Ag NPs) were fabricated using Aesculus hippocastanum fruit extract (ZnO–Ag@AHFE NPs), and their catalytic and antimicrobial properties were studied. The nanoparticles were identified using XRD, TEM, and FT-IR analyses, which confirmed their spherical morphology, uniform structure, and particle sizes ranging from 50 to 70 nm. The ZnO–Ag@AHFE NPs illustrated high antibacterial performance compared to the extract and ZnO NPs alone, achieving a minimum inhibitory concentration (MIC) of 125 µg/mL against Escherichia coli and Pseudomonas aeruginosa. Additionally, the ZnO–Ag@AHFE NPs exhibited outstanding photocatalytic efficiency, degrading methylene blue and rhodamine B dyes by 97.6% and 94.3%, respectively, surpassing the performance of other catalysts. Antioxidant assays revealed that the nanoparticles inhibited 85% of DPPH free radicals, underscoring their potential in biological applications. This study presents a green method using A. hippocastanum fruit extract, offering an innovative approach to enhance the antibacterial, catalytic, and antioxidant properties of ZnO–Ag NPs. These findings highlight the transformative potential of green synthesis strategies for the development of multifunctional nanomaterials.