Seed-mediated growth of gold nanoparticles using self-assembled monolayer of polystyrene microspheres as nanotemplate arrays

Arrays of noble metal nanoparticles show potential applications in (bio-)sensing,optical storage, surface-enhanced spectroscopy, and waveguides. For all suchpotential devices, controlling the size, morphology, and interparticle spacing ofthe nanoparticles is very important. Here, we combine seed-mediated growth withnanosphere lithography to study the controllable growth of gold nanoparticles (AuNPs), in which the self-assembly monolayer of polystyrene (PS) on a silicon surfaceis used to guide the modification of alkanesilanes and the subsequent adsorption ofgold seeds; seed-mediated growth is applied to controlling the morphology and sizeof Au NPs. The size of adsorption region (determining the number of adsorbed goldseeds) is controlled by etching PS microspheres with oxygen plasma or annealing PSmicrospheres at the glass transition temperature. The size and morphology of the AuNPs are controlled by changing growth conditions. In such a way, we have achievedthe dual control of the obtained Au NPs. Preliminary results show that this strategyholds a great promise. This approach can also be extended to a wide range ofmaterials and substrates.