DIFFER researcher Rifat Kamarudheen will defend his PhD thesis titled "Plasmon-Driven Synthesis of Hierarchical Nanostructures" on 6 July 2020. The defense will take place online.
The ability of plasmonic nanoparticles to focus light into nanoscale volumes has rendered them a wide variety of applications such as photodetection, nanofabrication, drug delivery, heterogeneous catalysis, and nanoparticle syntheses. These nanoparticles can redistribute the energy they pick up from light in multiple ways - by scattering light, by generating intense electromagnetic spots on their surface, by ejecting hot charge carriers and by photothermal heating of the nanoparticles. In typical plasmon-activated reactions, these processes occur simultaneously on ultrafast timescales and are therefore challenging to discern between them. Understanding the mechanism of plasmon-decay is key to rationally design efficient chemical processes. For example, if one is interested in activating a chemical reaction using intraband hot charge carriers, one should design nanoparticle morphologies with sharp features (tips and corners) which resonate at wavelengths above the interband threshold and ensure that the heat generation is minimal. In this thesis, Rifat Kamarudheen utilizes light-activated nanoparticle syntheses as as a platform to discern and quantify the contributions of plasmon-decay mechanisms.