Effect of the number ratio and size ratio on the formation of binary superlattices assembled from polymer-tethered spherical nanoparticles of two sizes†

Binary superlattices (BNSLs) with unique configurations are of great interest, attributed to the interaction between two kinds of nanoparticles, providing potential applications in sensing, electronic and optical fields. Here, polystyrene (PS) tethered spherical gold nanoparticles (AuNPs) with two core diameters spontaneously assembled into BNSLs via emulsion-confined self-assembly. BNSLs with specific stoichiometry and interparticle gaps of the NPs are prepared by tuning the number and size ratios of the two types of NPs. Moreover, after introducing long ligands, binary NPs are separated into macrophase separation or mixed together, depending on the interaction between polymer chains tethered to the AuNPs. Finally, PS-tethered AuNPs provide more possibilities for fabricating multifunctional BNSLs.