Seed mediated synthesis of highly stable CTAB capped triangular silver nanoplates for LSPR sensing

Abstract

Triangular silver nanoplates synthesized using conventional method with trisodium citrate as capping agent shows degradation of its sharp edges over a period of time making them suitable for use only in a limited time-frame. In this work, we present a new approach to synthesize triangular nanoplates using seed mediated method and cetyltrimethylammonium bromide (CTAB) as a single capping agent in very low concentration of 0.4 mM. The seed nanoparticles as well as nanoplates synthesized in this work showed higher stability over an observation period of ten days. Also, the method allows the fine tuning of nanoplate size by tuning the seed volume in the synthesis process. The synthesized nanoplates were examined morphologically as well as through UV–vis spectroscopy utilizing lab-built setup. These nanoplates also show good bulk refractive index sensitivity of 167 nm/RIU for ∼45 nm edge length triangular nanoplates.