Precise control of silver nanoplate dimensions and optical properties via pH, EDTA and AMP mediated synthesis

Abstract

We present a seed-mediated synthesis method for producing silver nanoplates (AgNPTs) with customizable size and thickness, ensuring high yield and precise optical properties. This approach leverages ethylenediaminetetraacetic acid (EDTA) as a key component in the synthesis process, utilizing small single-crystal silver seeds. The interaction between Ag+ ions and EDTA at varying pH levels dynamically regulates silver complexation and reduction kinetics during seed overgrowth, leading to the formation of truncated nanoplates with superior optical responses. By adjusting the pH within the range of 8–10.5, we can manipulate the growth of the nanoplates, enabling a flexible optical response ranging from 519 to 1006 nm due to changes in their size and thickness. Additionally, nanoplate overgrowth extends plasmon resonance up to approximately 2000 nm. The incorporation of Adenosine 5′ monophosphate (AMP) not only enhances nanoplate stability but also allows for precise thickness adjustment independent of growth kinetics. This method provides a systematic approach to tailor nanoplate morphology and optical properties with unprecedented precision. The role of EDTA is attributed to its complexation ability with Ag+ and its assistance in facet evolution, supported by density functional theory (DFT) simulations of surface energies modified by EDTA adsorption. Furthermore, DFT calculations confirm that AMP can further modify the surface energies of different facets, enabling precise thickness control