Unraveling the Self-Assembly of Heterocluster Janus Dumbbells into Hybrid Cubosomes with Internal Double-Diamond Structure

Liu, HK (Liu, Hong-Kai)^[ 1,2,3 ] ; Ren, LJ (Ren, Li-Jun)^[ 1,2,3 ] ; Wu, H (Wu, Han)^[ 1,2,3 ] ; Ma, YL (Ma, Yong-Li)^[ 1,2,3 ] ; Richter, S (Richter, Sven)^[ 4 ] ; Godehardt, M (Godehardt, Michael)^[ 4 ] ; Kubel, C (Kuebel, Christian)^[ 5,6 ] ; Wang, W (Wang, Wei)^[ 1,2,3 ]

JOURNAL OF THE AMERICAN CHEMICAL SOCIETY, 2019, 141(2): 831-839

DOI: 10.1021/jacs.8b08016

Abstract

Cubosomes are bicontinuous cubic-phase particles generated by amphiphile self-assembly with bicontinuous cubic phases, which creates an intricate network of interconnected nanochannels that endow these materials with special functions for advanced applications. On the other hand, clusters are an attractive class of molecules that exhibit intriguing functions and properties that differ from those of atoms and nanoparticles. Inspired by lipid self-assembly and attracted to the new functionalities of clusters, we prepared special heterocluster Janus dumbbells (HCJDs) composed of dissimilar nanoclusters: namely, a polyoxometalate and a polyhedral oligomeric silsesquioxane. HCJDs resemble conventional amphiphiles and, as such, they self-assemble in solution into faceted hybrid cubosomes via the transformation of vesicles into spongelike aggregates. Multiple mechanisms that lead to equilibrium, including molecular self-assembly, vesicle accumulation, membrane fusion, inner-structure reorganization, and cubic crystal growth, contributed to the overall process. On the basis of these results, we proposed a strategy for self-assembly from basic molecular design that goes beyond traditional amphiphiles to the construction of micro- or nanomaterials with hierarchical structures and advanced functions.