Electrochemical synthesis and absorption properties of gold nanorods

Suspended gold nanorods have been synthesized via an electrochemical method. The absorption spectrum features show two peaks at 520 nm and 650 nm, which result from the transverse and longitudinal surface plasmon resonance. The spectra at different growth stages indicate that the absorption peaks split and shift after electrolysis, which correspond to the anisotropy growth of nanorods. The quasi-static calculation results indicate that with increasing the mean aspect ratio of the nanorods, the longer wavelength absorption peak decreases and red shifts obviously, whereas the shorter wavelength absorption peak blue shifts slightly.