Preparation of gold nanorods of high quality and high aspect ratio

Abstract

We report the synthesis of gold nanorods (NRs) by seed-mediated growth method. A small amount of different shapes such as triangles, hexagons and a large amount of rods are obtained by varying the proportion of seed to metal salt, adding NaOH to growth solution as well as using the seed solution of CTAB-capped agent. The gold nanorod (NR) formation yield is improved. Meanwhile, the growth mechanism of high yield gold NRs is discussed. The high quality single size NRs can be separated from polydisperse samples using surfactant-assisted nanorod self-assembly. The gold NRs synthesized were characterized by transmission electron microscopy (TEM) and UV-vis spectroscopy.

Keywords

gold nanorods (NRs) / seed-mediated growth method / transmission electron microscopy (TEM) / growth mechanism of gold NRs

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