Maneuvering the growth of silver nanoplates: use of halide ions to promote vertical growth

Abstract

The unique shape and crystalline structure of Ag nanoplates provide an interesting model system for investigating the roles of capping agents in controlling the evolution of the nanostructure shape during growth. This article describes a simple approach to the synthesis of Ag nanoplates with well-controlled shapes in which halide ions (including Cl⁻, Br⁻, and I⁻) guide the well-defined kinetically controlled synthetic route. The presence of iodide ions promoted vertical growth in the nanoplate structure, resulting in small thick nanoplates. The time, during the nanoplate growth process, at which iodide ions were added could be adjusted to control the shapes of the Ag nanoplates by controlling the lateral and vertical dimensions of the nanoplates. This shape control method permitted tuning of the localized surface plasmon resonance (LSPR) peaks of the Ag nanoplates over the visible and near-IR regions of the spectrum.