From brush conformation to 3D Supraparticles: Programmable self‐assembly of polymer‐grafted nanoparticles in emulsion confinement

This review highlights recent advances in the self‐assembly of polymer‐grafted nanoparticles (PGNPs) within the three‐dimensional (3D) confinement of emulsion droplets to construct supraparticles with programmable superstructures. PGNPs serve as versatile building blocks, where the interparticle interactions can be precisely tailored by engineering the macromolecular parameters of the grafted chains, such as chemical composition, grafting density, and molecular weight. In emulsion systems, the interplay between interfacial energy, entropic forces, and isotropic shrinkage during solvent evaporation drives the formation of highly ordered architectures, including Mackay icosahedral supracrystals and symmetry‐broken polyhedral clusters that are often inaccessible in bulk phases. We provide an in‐depth analysis of the assembly mechanisms, focusing on the role of polymer brush conformation and the physical constraints imposed by the emulsion environment. Furthermore, the potential applications of these 3D supraparticles in next‐generation plasmonic sensing, spatially compartmentalized catalysis, and shape anisotropy‐directed assembly are discussed, offering a perspective on future research directions in the field of programmable colloidal matter.