We report the construction of dumbbell-shaped hybrid molecules for programming their hierarchical supramolecular nanostructures through a synergetic self-assembly. Our first dumbbell-shaped hybrid molecule is a POM-organic-POSS cocluster produced by covalently coupling a POM cluster and a POSS cluster together through an organic tether. Structural analyses demonstrated a highly ordered lamellar morphology with a 4.9 nm periodicity, indicating a strong thermodynamic force driving a nanoscale phase separation of the POM and POSS blocks. The POM clusters were arranged in an orderly fashion within the POM-containing layer with a 1.38 nm periodicity because of fixed shape and size of the cluster. This investigation provides in-depth understanding of how to construct hierarchical supramolecular nanostructures at a nanoscale less than 5 nm by manipulating and controlling the topological shape of hybrid molecules.

Clusters with diverse structures and functions have been used to create novel cluster-assembled materials (CAMs). Understanding their self-assembly process is a prerequisite to optimize their structure and function. Herein, two kinds of unlike organo-functionalized inorganic clusters are covalently linked by a short organic tether to form a dumbbell-shaped Janus co-cluster. In a mixed solvent of acetonitrile and water, it self-assembles into a crystal with a honeycomb superstructure constructed by hexagonal close-packed cylinders of the smaller cluster and an orderly arranged framework of the larger cluster. Reconstruction of these structural features via coarse-grained molecular simulations demonstrates that the cluster crystallization and the nanoscale phase separation between the two incompatible clusters synergistically result in the unique nano-architecture. Overall, this work opens up new opportunities for generating novel CAMs for advanced future applications.

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We report our findings on the macromolecule-to-amphiphile conversion process of a polyoxometalate-polymer hybrid and the assembled hybrid vesicles formed by aggregation of the hybrid amphiphile. The polyoxometalate-polymer hybrid is composed of a polyoxometalate (POM) cluster, which is covered by five tetrabutylammonium (Bu(4)N(+)) countercations, and a polystyrene (PS) chain. Through a cation-exchange process the Bu(4)N(+) countercations can be replaced by protons to form a hybrid amphiphile composed of a hydrophilic, protonated POM cluster and a hydrophobic PS chain. By implementing a directed one-dimensional diffusion and analyzing the diffusion data, we confirmed that the diffusion of solvated protons rather than macromolecules or aggregates is the key factor controlling the conversion process. Once the giant hybrid amphiphiles were formed, they immediately assembled into kinetically favored vesicular aggregates. During subsequent annealing these vesicular aggregates were transformed into thermodynamically stable vesicular aggregates with a perfect vesicle structure. The success in the preparation of the POM-containing hybrid vesicles provides us with an opportunity of preparing POM-functionalized vesicles.

A bottom‐up strategy for the preparation of hierarchical hybrid materials with good thermostability is reported. The hybrid molecule was constructed from a Wells–Dawson‐type polyoxometalate (POM) cluster and a poly(ethylene glycol) (PEG) chain through covalent‐bond formation. The large distinction between the POM cluster and PEG chain results in a microphase separation to form POM and PEG layers that further alternatively arrange into hybrid lamellae with a sub‐20 nm thickness. Then the hybrid lamellae could simultaneously organize into spherulitic superstructures. Because of this hierarchical structuring, strong electrostatic interactions between POM clusters are maximized within the POM layers. This gives rise to thermostability. Structurally, the hybrid lamellae and the superstructures are unchanged, even at 160 °C, and indeed the shear storage modulus of the hybrid material remains nearly constant within this same temperature range. This study demonstrates the concept of bottom‐up hybridization, in which rationally selecting building blocks, designing the hybrid molecule, and then manipulating hierarchical structures can generate thermostable hybrid materials.

The heterogenization of a polyoxometalate (POM) catalyst by direct covalent immobilization in polymer matrices with uniform macropores and high specific surface areas was reported. Via click chemistry, organically modified POM clusters were mainly "clicked" on the functionalized channel surface of a macroporous resin. The appraisement of the catalytic performance via catalysis on tetrahydrothiophene (THT) oxidation, demonstrates that the solid catalyst is efficient and has a high selectivity. More attractively, it could be reused several times without detectable catalytic activity loss. And no POM species were detected in the filtrate, stemming from the strong covalent bonding between the POM clusters and the macroporous resin surface. Evidently, such a catalyst heterogenization strategy helps to overcome the fatal leaching problem. Therefore the POM heterogeneous material can become an ideal candidate for industrial processes and will also have great potential in practical application not only for oxidative catalysis.

Cluster materials have attracted much attention because of their unique chemical and physical properties, hitherto unseen in bulk materials. Inspired by the lipid self‐assembly principle, a series of heterocluster Janus molecules (HCJMs) with atomic precision have been rationally designed and synthesized by connecting different clusters via covalent bonds for the construction of nanomaterials and nano‐objects. Due to their amphiphilicity, HCJMs self‐assemble into cluster‐containing nanomaterials or nano‐objects with versatile ordered structures beyond those observed in conventional crystals. Their hybrid composition and nanoscale size are also greatly advantageous in the study of their fine structure by electron microscopy techniques, and enable their formation mechanisms to be unraveled. Finally, the influence of the characteristics of the HCJMs on the structure and properties of the self‐assembled nano‐objects are explored comprehensively. This synthesis strategy will promote further development of cluster materials with advanced functions via rational molecular design toward the construction of hierarchical nanostructures via molecular self‐assembly.