Size-tunable synthesis of gold nanorods using pyrogallol as a reducing agent

A novel and facile seed-mediated method for the preparation of monodispersed gold nanorods (GNRs) is presented by introducing pyrogallol as a reductant. Fast Fourier transformation of high-resolution transmission electron microscopy reveals that the synthesized GNRs are single crystalline. The longitudinal surface plasmon resonance of GNRs can be finely tuned by varying silver ion concentrations or seed amounts. Also, both thick (diameter > 30 nm) and thin (diameter < 10 nm) GNRs with exceptional monodispersity can be well prepared by this method. These findings indicate that this method has a greater performance in controlling the morphology of GNRs than that of traditional approach with ascorbic acid as a reductant.