{111}-Faceted silver nanoplates: an automated and customized design for functionality

Abstract

Silver nanoparticles (Ag-NPs) exhibit the highest efficiency of localized surface plasmon resonance (LSPR) excitation that can be tuned to any wave length in the visible spectrum. Its performance depends to a large extent on its physicochemical characteristics such as size and shape; which, in turn, can be modulated by the selective growth of their crystalline facets. We used a simple direct chemical reduction method with a precise manipulation of seed-mediated growth control through an automated single-phase continuous flow-batch system to induce customized geometries on Ag-NPs. Optimization of the experimental design was carried out from a multivariate analysis, where the height/width ratio of LSPR band was used as response signal. Proposed methodology controls the critical steps in the synthesis of Ag-NPs that modulate their morphology to attain customized surface plasmon resonance in an interval of 380 nm (spherical-shaped nanoparticles) to 925 nm ({111}- faceted prism-shaped nanoplates) absorptions, leading to a versatile platform to extend their potential applications. Although the present work focused on silver nanoparticles, we believe that this methodology can be extended to any free-electron metals.