Phytogenic single-step assembly of Ag/rGO nanocomposites using Citrus macroptera peel extract: A multifunctional platform for catalysis and antibacterial applications

Herein, we report the phytogenic, single-step synthesis of silver/reduced graphene oxide (Ag/rGO) nanocomposites utilizing Citrus macroptera peel extract as a sustainable, dual reducing and stabilizing agent. Spectroscopic and diffractometric analyses (UV–vis, FTIR, Raman, EDX, and XRD) confirmed the synchronized bio-reduction of graphene oxide (GO) and silver ions (Ag + ), yielding highly crystalline metallic ‘Ag’ anchored on an exfoliated reduced graphene oxide (rGO) matrix. Electron microscopy (SEM and TEM) analyses established the homogeneous immobilization of ultrafine, spherical silver nanoparticles (AgNPs) in the tens-of-nanometers scale across wrinkled, semi-transparent, and exfoliated rGO nanosheets. Benefiting from a synergistic interfacial electron-transfer mechanism, the Ag/rGO nanocomposite demonstrated vastly superior catalytic efficiency for 4-nitrophenol reduction (9 min, 97.5 s −1 g −1 ) compared to pristine AgNPs (18 min, 87.2 s −1 g −1 ) and their corresponding physical mixtures (AgNPs & rGO synthesized using same extract). Furthermore, the hybrid material exhibited potent, broad-spectrum antibacterial activity against critical pathogens, including Escherichia coli , Staphylococcus aureus , Vibrio cholerae , and Salmonella typhi . This study establishes a green, waste-to-wealth fabrication strategy for multifunctional nano-architectures, offering potential solutions for environmental remediation and biomedical applications.