Plasmonic hot-nanocavity: multi-step synthesis of shape-complex nanoparticles for near-field focusing

As life has evolved from simple molecules into complex biological systems through countless reactions, adaptations, and iterative steps over millions of years, the synthesis of plasmonic components has similarly advanced toward increasingly intricate structures. The rational design of shape-complex nanostructures is now achievable through multistep synthetic routes and precisely engineered chemical toolkits. Here, we present the synthetic pathways of plasmonic nanostructure synthesis, demonstrating how sequential reactions and combinatorial strategies facilitate the creation of plasmonic hotnanocavities, designed for near-field focusing. These complex nanocavities act as clusters of hot zones, enabling the formation of 'hot cavities'—defined as multiple strong and uniformly distributed hot zones emerging across individual plasmonic nanoparticles.