Hydrothermal synthesis of Ag/Ni15O16 nanocomposite: Exploiting green chemistry for environmental and biomedical applications

Nanomaterials have remarkable potential to open novel opportunities in materials science, biological research, and the photocatalytic industry. Globally increasing threats, health issues, and environmental problems have driven ambitious research toward sustainable resolutions. Nanomaterials possess promise; yet, their efficacy is limited by inadequate conductivity and conventional synthesis methods. Novel oxygen-rich nickel oxide (Ni15O16) nanoparticles (NPs) were obtained in the present research work, replacing stochiometric NiO, and their properties were improved by forming a nanocomposite (NC) with silver metal using a facile green hydrothermal method. Citrullus colocynthis (L.) Schrad dry fruit extract was used as a reducing and stabilizing agent. The synthesized nanomaterials were approximately characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), Fourier-transform infrared spectroscopy (FTIR), and Energy-dispersive X-ray spectroscopy (EDX). The synthesized nanoparticles and nanocomposites have been evaluated for their potential to degrade organic dyes and their antimicrobial effects. The Ag/Ni15O16 NCs demonstrated exceptional photocatalytic degradation against the Congo red (CR) dye, with 99.6 % degradation achieved in 70 min, as reported in the results. With a percentage zone of inhibition (ZOI) of 96.057 % against the Phytophthora infestans fungal strain and a ZOI of 27 ±0.4 mm for the E. coli and 24 ±0.5 mm for the S. aureus bacterial strains, Ag/Ni15O16 NCs show remarkable antifungal and antibacterial potential. Ag/Ni15O16 exhibits significant antioxidant potential with a scavenging capacity of 81.90 % and 90.3 % for 2,2-Diphenyl-1-Picrylhydrazyl Radical Scavenging Capacity (DPPH RSC) and Hydroxyl Radical Scavenging Capacity (HRSC), respectively.