Shape control synthesis of multi-branched gold nanoparticles

Multi-branched gold nanoparticles (MBGNs) were prepared by a seed-mediated growth method using assistance of AgNO3 and cetyltrimethylammonium bromide (CTAB) acting as the surface modifiers of the particle. The size of MBGNs was changed from 150 to 1500 nm, in which the branches with length up to 100 nm were formed. The formation of the branches was discussed as the selective growth of surfaces restricted by the Ag+–CTAB complex. The surface plasmon resonance properties were strongly affected by the morphology of MBGNs and tuned over the wide wavelengths.