Unraveling the physical chemistry and materials science of CeO2-based nanostructures

CeO2-based nanostructures have recently aroused interest for various applications because of their higher OSC and redox properties, allowing them to facilely switch between the oxidation states of Ce4+ and Ce3+. There are many studies that have been focused on the morphology-dependent catalysis and identification of the true active sites during catalysis reactions. Probing the intrinsic properties of CeO2 nanostructures, including the surface structure and reduction, oxygen vacancy, grain boundary, morphology, and dynamic structure under environmental conditions, is essential in clarifying their physical and chemical properties and expanding their potential applications. In this review, we summarize recent significant achievements in characterizing CeO2 nanostructures and related catalytic phenomena through advanced techniques. Several studies using model CeO2 catalysts have been selected to show the importance of strong metal-support interactions. A deep insight into the active sites in morphologically controllable CeO2 that exposes the highly active facets is expected to guide the design of nanocatalysts.