Distinct Contributions of the Surface/Interface/Core of Metal Clusters to Catalytic Properties

ConspectusTraditional metal nanoparticles have been widely utilized as heterogeneous catalysts in both fundamental scientific research and industrial applications. Their catalytic performances are commonly statistical and represent averaged results from all of the nanoparticles due to their inherent size polydispersity and structure heterogeneity. Recently, metal clusters (1-2 nm) with precise compositions and well-defined structures have provided opportunities to precisely correlate the catalytic properties with the structure and composition of the clusters at the atomic level. Specifically, the distinct metal core, interface, and surface structures of these clusters render them ideal for exploring the contributions of the surface/interface/core of cluster-based catalysts to catalytic properties.In this Account, we introduce the correlation of the catalytic properties of clusters with their ligand, interface, and metal kernel, ultimately mapping out the key factors that dictate the catalytic activity and selectivity. We first preview atomically precise clusters and the structural characteristics of the surface, interface, and kernel. Then, we emphasize the modulation of catalytic properties of cluster catalysts through the ligand, interface, and core. (i) Surface ligand: An efficient surface modification via ligand exchange is able to not only remarkably enhance the catalytic activity but also effectively modulate the product selectivity. (ii) Metal-ligand interface and cluster-cluster interface: The metal-ligand interface can enable the catalytic sites to directly control the whole catalytic process through the synergy between the metal atom and the ligand. Additionally, the interfaces between the clusters and their surrounding environment can cooperatively tailor the catalytic activity and selectivity. (iii) Metal core: The one-atom variation in the cluster kernel composition can effectively tune the overall electronic structures of clusters, thereby indirectly improving their catalytic activities. Furthermore, the central atom within an open core can also act as the active site to directly participate in and facilitate the catalytic reaction. Ultimately, looking to the future of catalysis science, there are still many challenges, but atomically precise metal clusters deserve more future efforts to unravel fundamental catalysis. Therefore, we offer several perspectives on the future research of precise catalysis using atomically precise cluster catalysts. We anticipate that this Account can provide fundamental insight into the unique contributions of the surface/interface/core of heterogeneous catalysts to their overall catalytic performances. By learning these fundamental principles, we will ultimately be able to design high-performance catalysts for a variety of catalytic processes.