Abstract:Rod-like gold nanoparticles can be formed from HAuCl4 aqueous solution with ultraviolet (UV) irradiation in the absence of templates, avoiding possible poisonous surfactant embedded into the surface of functional gold nanoparticles applied in biomedicine. The aspect ratio of nanorods ranges from 1.1 to 4.4 with the concentration of HAuCl4 0.2 mM, which can be verified by HRTEM images and the absorption spectrum. It is found that the nanocluster with several atoms occurs prior to the formation of nanorods, h...