green synthesis and characterization of core-shell fullerene-silver hybrid nanocomposite by means of citric acid

Hybrid nanomaterials combining metals with fullerene provide unique synergistic properties, enabling the development of a new generation of advanced materials. this study reports the green synthesis and comprehensive characterization of a novel core-shell hybrid nanomaterial composed of silver nanoparticles (ag nps) encapsulated within a fullerene-citric acid (fca) nanocomposite matrix. the fca nanocomposite was first synthesized via two distinct pathways: a conventional thermal method and a greener enzymatic approach utilizing novozym 435. this fca product served a dual function as both a reducing agent and a stabilizer in the subsequent synthesis of silver nanoparticles from silver nitrate. successful formation of the ester bond in fca was confirmed by ft-ir spectroscopy, showing a characteristic peak around 1730 cm⁻¹. uv-vis spectroscopy of the final hybrid revealed two key absorption peaks, one at ~268 nm corresponding to the π-π* transitions of the fullerene moiety and a distinct surface plasmon resonance (spr) band at ~423 nm, confirming the formation of ag nps. electron microscopy (fesem and tem) analysis demonstrated spherical nanoparticles with an average size of approximately 25 nm and provided clear evidence of the core-shell structure, where ag nps form the core surrounded by the fca shell. the presented methodology offers an efficient route to stable fullerene-metal hybrid nanostructures with potential for advanced applications in catalysis, sensing, and biomedicine.