Controlled synthesis of gold nanoflowers assisted by poly(vinyl pyrrolidone)–sodium dodecyl sulfate aggregations

Gold nanoflowers with high-yield and good size monodispersity were synthesized in aqueous solution through a facile route under the assistance of poly(vinyl pyrrolidone) (PVP)–sodium dodecyl sulfate (SDS) aggregations. In this route, HAuCl4 was directly reduced by PVP without any additional reducing agents and sodium hydroxide (NaOH) was added to induce the formation of nanoflowers. The synthesized nanoflowers are 100 nm in dimension consisting of a solid core and many short and obtuse protrusions (5–10 nm). UV–vis spectroscopy and transmission electron microscope (TEM) were used to monitor the shape evolutionary process of the nanoflowers to get a better understanding on their formation mechanism. The presence of PVP–SDS aggregations at a proper SDS concentration was essential to the synthesis of typical three-dimensional (3D) nanoflowers with many protrusions. Moreover, the influences of SDS, NaOH and HAuCl4 concentrations on the morphology of the products were investigated in detail.