Reversible interconversion and functional division of highly dispersed Cu species during CO + NO reaction

Abstract

CuOCeO2 system has been widely studied in recent decades. Electronic-scale understanding the function and evolution of Cu species in catalytic reaction is benefit for exploring the catalytic potential of Cu-based catalysts. In this work, Cu+-rich CuOCeO2 catalysts was prepared by template method. The studies show that the synergistic effect of CuO/CeO2 is benefit the reversible interconversion between Cu+ and Cu0, and the rapid conversion between Cu+ and Cu0 contribute the high catalytic performance. Cu+ is responsible for the oxidation of CO, and Cu0 is dedicated to the selective reduction of NO. The isolated energy levels of the Cu species near the Fermi levels coordinate with Ce 4f orbitals for the electron transfer between the two phases. This electronic-level description of Cu evolution should have important guiding significance for the exploration of the potential of Cu-based catalysts.