Synthesis of Silver Nanodisks Using Polystyrene Mesospheres as Templates

The remarkable size and shape dependence of physical, optical, and electronic properties of metal and semiconductor nanocrystals make them compelling components of modern materials chemistry.1-3 When spherical metal particles are transformed into nanoscale rods or triangular prisms, the surface plasmon resonances are strongly affected, typically red-shifting and even splitting into distinctive dipole and quadrupole plasmon modes.4 Colloid chemists have recently made much progress in preparing monodispersed spherical nanocrystals via ambient temperature wet-chemical routes or organometallic methods.2 Although the synthesis of spherical nanocrystals is well developed for many materials, systematic manipulation of the shapes of nanocrystals is a significant challenge. Recent work devoted to making nonspherical nanocrystals via anisotropic inorganic nanocrystal growth in liquid media (including electrochemical growth) has yielded Au rods,5 BaCrO4 rods,6 TiO