GOLD NANORODS - ELECTROCHEMICAL SYNTHESIS AND OPTICAL-PROPERTIES

Aqueous solutions containing a high yield of suspended gold nanorods h ave been successfully synthesized via an electrochemical method. The c ontrol of preparing gold nanorods with different aspect ratios can be attained. Their absorption spectral features show a dominant surface p lasma band corresponding to the longitudinal resonance, SP1, and its l ambda(max) shifts markedly to the red as the aspect ratio is increased . Meanwhile, the dependence of lambda(max) for longitudinal resonance on the mean aspect ratio shows a deviation from the classical electros tatic model prediction at mean aspect ratios around 4 +/- 1, where it limits the validity of the classical electrostatic approximation.