Core/Shell Gold Nanoparticles by Self-Assembly and Crosslinking of Micellar, Block-Copolymer Shells

摘要

Core/shell nanoparticle architectures, in which a layer of inorganic or organic material surrounds an inorganic nanoparticle core, have been investigated both as a means to improve the stability and surface chemistry of the core nanoparticle and as a way of accessing unique physical properties that are not possible from one nanomaterial alone. As examples, silica shells isolate metal and semiconductor particle surfaces from interfacial chemistry;[1], [2] gold shells allow covalent attachment of thiol ligands to particles[3] and generate unique optical signatures;[4] semiconductor shells increase the quantum yield of semiconductor nanoparticle cores;[5] and polymeric shells aid the compatibility of nanoparticles in polymer hosts.[6] Whereas inorganic shells are typically grown from the surface of the particle core, a number of methods have been described for generating organic polymer shells, including polymerization from particle-bound initiators,[7] direct attachment of functionalized polymers to surfaces,[8] layer-by-layer deposition,[9] and synthesis of the particle in the presence of polymeric ligand.[10], [11] In all of these cases, the specific chemical interaction of the particle surface and the surface-bound polymer must be explicitly tailored in order to form the shell.