Cluster-based materials: design and applications

fullerene is an example of such a cluster. Clusters, protected by ligands or supported on a substrate, can also form cluster-assembled materials with unique properties. In contrast, atoms in an existing crystal can be replaced by corresponding superatoms to form "cluster-based materials". While several perspectives and review articles have been published to highlight the unique structure- and composition-specific properties of isolated clusters and cluster-assembled materials, it is during the past few years that attention has been focused on cluster-based materials. This review focuses on the recent developments in the design, synthesis, and applications of clusters with uncommon properties and highlights their potential as building blocks of cluster-based materials. The topics include isolated clusters enabling unusual reactions, their role in the design and synthesis of materials such as super-electrides, solid state electrolytes with fast ionic conductivity and stable interfaces, moisture resistant hybrid perovskite solar cells, thermoelectric materials with high figure of merit, and a new class of single-superatom catalysts. Also outlined are the challenges and opportunities going forward.