Synthesis of the gold nanodumbbells by electrochemical method

The gold nanoparticles with novel dumbbells-like structures have been successfully fabricated by an electrochemical method using micelle template formed by two surfactants, the primary surfactant being cetyltrimethylammonium bromide (CTABr) and the co-surfactant being tetradecyltrimethylammonium bromide (TTABr). The shape of gold nanoparticles can be modified to form dumbbell structure by addition of acetone solvent during the electrolysis. The gold nanodumbbells have been determined to be single-crystalline with a face-centered cubic (FCC) structure by X-ray diffraction (XRD) analysis. The lattice constant calculated from this selected-area electron diffraction (SAED) pattern is 4.068 A. Transmission electronic microscopy (TEM) suggests that shape of gold nanodumbbell is fatter in two ends and thinner in the middle section to compare with the normal nanorod shape. These gold nanodumbbells exhibit aspect ratio (gamma) of around 3.