Synthesis and Surface Engineering of Plasmonic Nanoparticles

When light interacts with plasmonic nanoparticles, their free electrons are driven by the alternating electric field and collectively oscillate at a resonant frequency leading to a phenomenon known as surface plasmon resonance. The frequency and amplitude of the resonance are sensitive to particle size and shape, which determine how the free electrons are polarized and distributed on the surface. As a consequence, control of the size and shape of plasmonic nanoparticles represents the most powerful means to tailor and finely tune their optical properties. In this chapter, a few among the most important techniques enabling size/shape-controlled growth of metal nanoparticles will be reviewed. Some examples of postsynthesis nanoparticle purification and surface modification toward plasmonic applications will also be provided.