Biomimetic synthesis, characterization and mechanism of formation of stable silver nanoparticles using Averrhoa carambola L. leaf extract

Abstract Stable silver nanoparticles (SNPs) are synthesized using aqueous leaf extract (both dry and fresh leaf) of Averrhoa carambola L. The biomolecules present in the leaf extract played the role of reducing as well as stabilizing agents in making and stabilising silver nanoparticles which has been explained through mechanisms on the basis of results obtained from UV–vis analysis, FT-IR analysis, zeta potential, particle size analysis, DLS, TEM and reaction kinetics studies. The effect of process variables on the yield, particle size, shape, kinetics of formation and stability of nanoparticles was studied. The novelty of this present study is the synthesis of very stable SNPs in aqueous phase by a single step reaction at room temperature without using any external stabilizing agent and reducing agent which is not possible by the existing protocols. Study of the mechanism of formation and stabilization of SNPs by biomolecules of A. carambola L. yet is another important aspect of this work. This developed eco-friendly method for synthesis of SNPs could prove a better substitute for the existing protocols and thus can be an efficient alternative for the large scale synthesis of SNPs