Synthesis of silver nanoplates with controlled shapes by reducing silver nitrate with poly(vinyl pyrrolidone) in N-methylpyrrolidone

Abstract

This article describes a simple approach to the synthesis of Ag nanoplates with controlled shapes by reducing silver nitrate (AgNO₃) with poly(vinyl pyrrolidone) (PVP) in N-methylpyrrolidone (NMP). The hydroxyl end groups of PVP have been shown to serve as a mild reductant for the kinetically controlled synthesis of Ag nanoplates. Here, we demonstrated that Ag nanoplates with tunable size and aspect ratio could be formed with high yields in a kinetically controlled synthesis using NMP as the reaction medium. NMP plays a critical role in the formation and growth of the nanoplate morphology. The reaction time and weight ratio of PVP to AgNO₃ could both be adjusted to permit the shape-controlled synthesis of Ag nanoplates, that is, with control over the nanoplate size and aspect ratio. Shape control permitted tuning of the localized surface plasmon resonance (LSPR) peaks of these Ag nanoplates over the visible and near-IR regions.