Molecular models for Ce/Co oxides: insights into atomic structures and electronic properties

Doory Dan, Khalil A. Abboud, and George Christou*

University of Florida

Cerium dioxide nanoparticles (CNPs) have gained substantial interest in a wide range of fields owing to their superior catalytic activity over their bulk counterparts in various important chemical processes. With smaller CNPs becoming increasingly important, we have established molecular bottom-up routes to obtain ultra-small (< 3 nm) CNPs as molecular cerium-oxo-carboxylate clusters. These offer all the advantages of molecular chemistry, including their isolation as single-sized crystalline products, which enables structural characterization to atomic resolution by single-crystal X-ray crystallography. Given their strong resemblance to the bulk material, we classify these clusters as ‘molecular nanoparticles (MNPs)’. More recently, we have extended this approach towards CeO₂ MNPs with transition metals (such as Mn) supported on their surface. Interestingly, despite numerous 3d/4f clusters in the literature, there are no reports of Ce/Co clusters possessing structural features of the CeO₂ fluorite lattice. The structures and characterizations of a family of new Ce/Co clusters will be presented.