Quaternization-Assisted Assembly of Polymer-Tethered Gold Nanoparticles into Superlattices with a Tunable Structure

Programmable organization of functional inorganic nanoparticles(NPs) into well-defined hierarchical superstructures has raised considerableconcern due to the enhanced magnetic, electronic, and optical propertiesarising from the strong plasmonic coupling effect. However, the spontaneousself-assembly of inorganic NPs into uniform superlattices with thedesired or tunable shape remains a formidable challenge. Herein, wereport the quaternization-assisted hierarchical assembly of gold nanoparticles(AuNPs) tethered with polystyrene (PS) and quaternized poly-(2-vinylpyridine)(P2VP) ligands into controllable superstructures in emulsion droplets.The quaternization interaction between bromoalkyl molecular additives(e.g., C (n) H2n+1Br) and P2VP ligands results in the increase ofthe hydrophilicity degree of quaternized P2VP ligands and triggersthe interfacial instability of emulsion droplets, achieving the continuoustransformation of generated superstructures from solid assembliesto hollow colloidosomes and then to the multilayer sheet-like superlattices.Furthermore, the degree of quaternization can be readily tuned bythe added content of additives and the length of the alkyl chain,providing a unique and promising approach to prepare contrivable superstructuresand functional materials.