Multi-functionalization of lithographically designed gold nanodisks by plasmon-mediated reduction of aryl diazonium salts.

Plasmon-driven surface functionalization of nanoparticles is receiving increasing attention as it allows locally tailored chemical reactivity to be generated on the nanoparticle surface. The extension to surface multi-functionalization still represents a major breakthrough in chemistry. We address this issue by triggering regiospecific surface double-functionalization under plasmon excitation, using diazonium salts as surface functionalization agents.

Nanoplasmonics tuned "click chemistry".

Nanoplasmonics is a growing field of optical condensed matter science dedicated to optical phenomena at the nanoscale level in metal systems. Extensive research on noble metallic nanoparticles (NPs) has emerged within the last two decades due to their ability to keep the optical energy concentrated in the vicinity of NPs, in particular, the ability to create optical near-field enhancement followed by heat generation. We have exploited these properties in order to induce a localised "click" reaction in the vicinity of gold nanostructures under unfavourable experimental conditions. We demonstrate that this reaction can be controlled by the plasmonic properties of the nanostructures and we propose two physical mechanisms to interpret the observed plasmonic tuning of the "click" chemistry.