Controlling Dynamic Structural Transformation of Atomically Dispersed CuO_<i>x</i> Species and Influence on Their Catalytic Performances

Abstract

Understanding the dynamic structural transformation of subnanometric metal species is a key to the establishment of the structure–function relationship for heterogeneous catalysts composed of single atoms and subnanometric clusters. Unlike noble metal catalysts, the evolution of non-noble metal catalysts containing singly dispersed atoms and clusters during redox treatments and under reaction conditions has not been well understood yet. In this work, with spectroscopic techniques and aberration-corrected electron microscopy, the control of dynamic structural transformations of supported CuOx species (from single ions to nanoclusters and nanoparticles) by the combination of the redox and water treatment has been systematically studied. Furthermore, their catalytic properties for two deNOx reactions (NO + CO, NH3 + NO + O2) have also been demonstrated to be strongly related to the dispersion of Cu2+ species, providing insights into the active sites in these model reactions for deNOx applications.