Hollow Multi-Shelled Structures of CoO Dodecahedron with Unique Crystal Orientation for Enhanced Photocatalytic CO Reduction.

Structure and facet control are considered to be effective routes to enhance catalytic performance. We successfully synthesized hollow multi-shelled structures (HoMSs) of a CoO dodecahedron by adopting metal-organic frameworks (MOFs) as templates and using the sequential templating approach (STA). Importantly, owing to the topological arrangement of metal atoms in MOFs, the CoO nanocrystals in HoMSs are assembled in the desired orientation, forming a unique shell with dominant exposure of (111) facets. This process is defined as "genetic inheritance" in this work. In addition, these exposed facets possess high activity for photocatalytic CO reduction. Adding this to the properties inherited from HoMSs, i.e., multiple interfaces and strong solar light harvesting, these CoO HoMSs present high catalytic activity for CO photoreduction. The catalytic activity of quadruple-shelled (QS) CoO HoMSs was about 5 and 3 times higher than that of CoO nanoparticles and CoO HoMSs without facet control, respectively.