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Comprehensive Summary: Recent progress in colloidal synthesis has realized the preparations of uniform nanocrystal (NC) model catalysts with rich and well‐controlled morphologies that were employed to explore structure‐activity relationships of powder catalysts, similar to single‐crystal‐based model catalysts under ultrahigh vacuum conditions but can work at the same conditions as powder catalysts without the "materials gap" and "pressure gap". In this perspective, the CeO2‐based NC model catalysts with various morphologies are included and their relevant progresses are critically reviewed. The detailed descriptions of morphology‐controlled synthesis and characterizations of uniform CeO2 NCs, and morphology‐dependent catalysis of CeO2‐based NC model catalysts containing pure CeO2 NCs, CeO2‐supported oxide catalysts, and CeO2‐supported metal catalysts, provide us a comprehensive cognition in CeO2‐involved catalytic reactions and also open up a new approach for the fundamental studies of complex heterogeneous catalysis. Finally, a concept of oxide‐based NC model catalysts and outlook of oxide NCs acting not only as model catalysts for the fundamental study but also as the support in tailoring structures and optimizing performance of oxide‐involved catalysts are discussed. [ABSTRACT FROM AUTHOR]

Metal‐organic frameworks (MOFs) have attracted significant attention as porous catalyst platforms due to the synthetic modularity of these materials and the diversity of lattice‐confined catalytic active sites that are readily embedded within periodic crystalline frameworks. MOFs offer platforms to heterogenize molecular catalysts, stabilize novel coordination motifs, and leverage confinement effects in catalysis. Crystallinity allows diffraction‐based methods to be employed in the characterization of these catalysts. Access to crystalline MOFs typically requires reversible construction of the metal−ligand (M−L) bonds that connect the SBUs, which provides a mechanism to anneal defects during crystallization. While the required M−L bond reversibility is often promoted by synthesis at elevated temperature, access to crystalline materials based on either transition metals with characteristic slow exchange kinetics or highly basic donor ligands remains a synthetic challenge. Here, we highlight synthetic strategies that leverage M−L exchange kinetics to access MOFs based on kinetically inert ions and extensions of these strategies to the assembly of atomically precise multimetallic materials. [ABSTRACT FROM AUTHOR]