Synthesis of crooked gold nanocrystals by electrochemical technique

In this article, we demonstrate the synthesis of crooked gold nanocrystals (CGNCs) by an electrochemical technique using micelle templates formed by two surfactants with different amounts of isopropanol solvent, the primary surfactant being hexadecyltrimethylammonium bromide (C(16)TABr) and the cosurfactant being tetradodecylammonium bromide (TC(12)ABr). To investigate the influence of isopropanol solvent on the CGNCs, the amount of isopropanol was varied in the range from 50 to 300 mu L. It was found that the aspect ratios (gamma) of CGNCs were in the range from 1.06 to 1.46, and the UV-vis optical absorption measurement revealed a pronounced redshift of the surface plasmon band from 532 to 560 nm. The CGNCs were composed of many large gold grains with small gold nuclei, and it was determined that several grains are present within each of the CGNCs using a dark-field transmission electron microscopy (TEM) image. It is suggested that the CGNCs have a polycrystalline structure. The CGNCs have been determined to be pure gold with a face-centered cubic (fcc) structure by electron diffraction (ED) analysis.