Hierarchical ceria nanoarchitecture enabling accelerated lattice oxygen activation for efficient redox reactions

Precisely engineered nanoarchitectures can unlock new catalytic active sites. We introduce nanomace, a ceria (CeO2) nanostructure integrating cubic and rod-like domains within a single framework. The chemically coherent interface generates highly active oxygen sites, enabling faster CO conversion than conventional morphologies and surpassing physically mixed rods and cubes. Enhanced lattice oxygen reactivity is confirmed by facile redox cycling in in situ Raman and synchrotron-based ambient-pressure XPS, and fast lattice oxygen exchange in isotopic studies. As a support, nanomace amplifies activity across multiple reactions: Au-, Pd-, and Rh-loaded nanomace outperform commercial, rod, and cube CeO2 by up to 14.4-fold in water gas shift, CH4 combustion, and N2O decomposition. Molecular dynamics simulations reveal preferential lattice oxygen activation at the integrated interface. By establishing interface sites as uniquely reactive, nanomace demonstrates structural integration as a powerful strategy for next-generation redox catalysis.