Synthesis and Manipulation of High Aspect Ratio Gold Nanorods Grown Directly on Surfaces

Here we describe the synthesis of Au nanorods directly on glass surfaces using seed-mediated deposition of Au from AuCl4- onto surface-attached 3?5 nm diameter Au nanoparticles (AuNPs) in the presence of cetyltrimethylammonium bromide (CTAB). The average length (200 nm to 1.2 ?m) and aspect ratio (6?22) of the nanorods increases with increasing AuCl4- concentration. Short, low aspect ratio Au nanorods are manipulated with an atomic force microscopy (AFM) tip, while longer, high aspect ratio nanorods are bent and broken with the AFM tip.