We report the synthesis of various shaped silver nanoparticles mediated by ZnCl2 salt. It has been demonstrated that the salt, PVP/AgNO3 mole ratio, and the type of polyol (EG, DEG,and GL) significantly determined twinning probability, which is an index of silver seed growth origin. High twining probability arising from low PVP/Ag+ ratio and 50 mole% salt favours 1D grown nanowires and nanorods, whereas low twining amidst high mole% salt (150) in DEG offered 2D grown nanoflakes and nanosheets. Other shaped silver nanoparticles have been found. Accidentally, we arrived at a core-shell heterostructure of Ag-ZnO nanocomposite with Ag core enrichment when mole% of the salt was made up to 300. Growth kinetic of nanosphere obtained was monitored, and effect of salt mediation was found crucial. Structural evolution of shaped Ag nanoparticles and nanocomposites have been monitored using XRD, SEM, EDX, TEM, and UV/vis. 1. Introduction Nanostructured materials have received broad attention due to their distinguished performance in electronics, optics, and photonics [1]. With reduction in size, novel electrical, mechanical, chemical, and optical properties are introduced, which are largely believed to be the result of surface and quantum confinement effects. They have been widely exploited for use in photography, catalysis, biological labeling, photonics, optoelectronics, information storage, and formulation of magnetic ferrofluids [2–4]. Among the various metal nanostructures, silver nanoparticles (SNs) have been widely investigated because they exhibit unprecedented optical, electronic, and chemical properties, depending on their sizes and shapes, thus opening many possibilities for diverse technological applications [5–7]. Generally, silver nanoparticles have been produced by various methods including chemical reduction of silver ions with or without [8, 9] stabilizing agents, thermal decomposition of organic solvents, and electrospining [10]. Using these methods [8–14], silver nanoparticles with spherical, octahedral, tetrahedral, hexagonal, cubic, wire, coaxial cable, triangular prism, disc, and belt shapes have been produced. Apart from metal-silver nanobimetallics [15–19], functionalization or core-shell of silver-metal oxide nanocomposites is limited in the literature. Ag-ZnO electrical contact material was only recently produced using mechanochemical synthesis route [20]. Polymer functionalized silver has been reported [21]. Furthermore, the presence of various ions has been shown to influence the shape and size of metallic nanostructures produced via the
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