Cluster-assembled materials: Ordered structures with advanced properties

Abstract

Cluster-assembled materials (CAMs) present delicate structures and tailored properties, which have gained extensive interest in recent years. Due to the noncovalent linkage and size of sub-1 nm, clusters present polymer-like solution behaviors distinct from conventional nanocrystals, whereby a variety of CAMs with different constructions have been fabricated. To our knowledge, the morphologies and properties of CAMs are closely connected, which are strongly dependent on the structure and coordination state of cluster building blocks. For the CAMs with superior performances, the specific arrangement and surroundings of clusters at subnanometer scale usually result in well-organized structures. In this review, we will summarize the recent progress of CAMs with highly ordered structures and advanced properties, where polyoxometalate cluster assemblies as well as cluster–nuclei co-assemblies are involved. The application potentials of CAMs are then discussed, especially on the cluster arrangements and interactions at subnanometer scale. However, current researches are far from reaching the point, and future efforts are needed before the nature of cluster-based nanostructures can be sufficiently revealed. We hope this article can offer unique insights and instructive understanding to the CAMs.