Size-controlled synthesis of gold bipyramids using an aqueous mixture of CTAC and salicylate anions as the soft template

Abstract

One-dimensional (1D) gold (Au) bipyramids are successfully synthesized through a facile seed-mediated method using cetyltrimethylammonium chloride (CTAC), Au seed nanoparticles, Ag⁺ ions, and ascorbic acid. The length and optical properties of the synthesized Au bipyramids are controlled with precision by varying the amount of salicylate anions (Sal⁻) added during the synthesis. The micelles formed from CTA⁺–Sal⁻ mixtures in aqueous solutions act as effective templates for the size-controlled synthesis of 1D nanocrystals.