Hollow Mn-doped CeO2@Co3O4 catalyst for NO reduction by CO

Selective catalytic reduction of NO using CO (CO-SCR) is a promising technology for the purification of NO in the flue gas. However, the presence of O2 significantly inhibits the activity of the CO-SCR catalyst. Herein, we synthesize a hollow Mn-doped CeO2@Co3O4 catalyst (Mn-CeO2@Co3O4), which achieved 82% NO conversion, 100% CO conversion, and 78% N2 selectivity under 5 vol% O2 at 200 °C, superior to those of CeO2@Co3O4 and Co3O4@CeO2 catalysts. The characterization results indicate that the strong electronic interaction at the heterointerfaces between Co3O4 and CeO2 plays a crucial role in promoting selective adsorption of NO. Furthermore, the Mn doping into the Co3O4 lattice of the catalyst facilitates the conversion of N2O intermediates, thereby enhancing the overall activity. This research provides a new strategy for the design and synthesis of CO-SCR catalysts.