Patchy Nanoparticles with Well-Defined Valency and Configuration via Surface Patterning of Grafted Amphiphilic...

Using Brownian dynamics simulations, this study examined the surface patterning and directed assembly of hairy nanoparticles (NPs) fabricated by uniformly grafting a single NP core with multiple copolymers, each featuring an inner solvophobic block (A) and an outer solvophilic block (B). In a selective solvent, these A blocks initially collapse into numerous small nanodomains (patches) that subsequently fuse to minimize interfacial energy─a process that reduces patch number (valency) and increases patch size, ultimately yielding patchy NPs with well-defined valency and configuration. By systematically varying the NP diameter, the A-block length, the grafting density, the A-A interaction parameter, and the B-to-A block length ratio, we achieved patchy NPs spanning a broad valency range from n = 1 to 12. They adopt spherical, linear, triangular, tetrahedral, triangular dipyramidal, octahedral, pentagonal dipyramidal, snub disphenoidal, triaugmented triangular prismatic, gyroelongated square dipyramidal, augmented sphenocoronal, and icosahedral configurations. A linear relationship was observed between the valency and the average ratio of NP diameter to A-blocks' unperturbed root-mean-square end-to-end distance for each corresponding valency. The linear slope is influenced by both the grafting density and the B-to-A block length ratio but not by the A--A interaction parameter. Finally, employing the obtained multivalent patchy NPs (X, n = 1-12) as central hubs and 1-valent patchy NPs (Y) as satellite ligands, we demonstrated the directed assembly of a series of colloidal molecules (CMs, XY₁-XY₁₂), with architectures faithfully replicating the patch configurations of X. Our findings lay the groundwork for the rational design of customized patchy NPs with higher valency and their corresponding CMs.