Nanotechnology

Nanocrystal

Organic chemistry

Nanostructure

Surface energy

Nucleation

Adsorption

Engineering

Physical chemistry

Surface diffusion

Composite material

Surface engineering

Chemistry

Metallurgy

Materials science

Metal

Ostwald ripening

Chemical engineering

Angewandte Chemie International Edition

Engineering the nucleation and growth of plasmonic metals (Ag and Au) on their pre‐existing seeds is expected to produce nanostructures with unconventional morphologies and plasmonic properties that may find unique applications in sensing, catalysis, and broadband energy harvesting. Typical seed‐mediated growth processes take advantage of the perfect lattice match between the deposited metal and seeds to induce conformal coating, leading to either simple size increases (e.g., Au on Au) or the formation of core–shell structures (e.g., Ag on Au) with limited morphology change. In this work, we show that the introduction of a thin layer of metal with considerable lattice mismatch can effectively induce the nucleation of well‐defined Au islands on Au nanocrystal seeds. By controlling the interfacial energy between the seed and the deposited material, the oxidative ripening, and the surface diffusion of metal precursors, we can regulate the number of islands on the seeds and produce complex Au nanostructures with morphologies tunable from core‐satellites to tetramers, trimers, and dimers.

Surface Engineering and Controlled Ripening for Seed‐Mediated Growth of Au Islands on Au Nanocrystals