In Situ TEM Study of Atomic Level Phase Transformation

Ceria (CeO₂) and cerium-based oxides can release lattice oxygen under oxygen lean condition and storage oxygen under oxygen rich condition. This property, characterized as the oxygen storage capacity (OSC) or redox functionality, has made it a material of considerable interest in applications such as vehicle three-way exhaust clean-up, water-gas shift reactions, gas sensors, carbon dioxide capture, and fuel cell electrodes. In this talk, I will present some recent progress on understanding atomic-level redox behavior of cerium-based oxides using environmental transmission electron microscopy (E-TEM), and on the synthesis and characterization of shape/crystal structure-controlled CeO₂ and CeO₂-ZrO₂ for designing new automotive catalytic converter washcoat and catalyst supporting materials.