Aspect ratio controlled synthesis of gold nanorods

Au nanorods were synthesized by using seed-mediated methods. The aspect ratio of the Au nanorods was controlled by temperature and the amount of surfactant used and the rods were characterized by TEM, HRTEM and UV-VIS spectrophotometer. Au nanorods with high aspect ratio could be prepared by decreasing the temperature used and controlling the surfactant concentration. The UV-VIS absorption spectra of the nanorods also showed variations in the aspect ratio. These results suggest that Au nanorods form, via an anisotropic growth mechanism, and that the surfactant plays a role in this process.