Microscopic Investigation of CO Oxidation Reaction by Copper–Manganese Oxide Catalysts

The catalytic oxidation of CO is a significant process for environmental and human health protection. The CuMnO_x (hopcalite) catalyst is a good candidate for the CO oxidation reaction, owing to advantages such as low cost and good catalytic activity at low temperature. In this study, a combination of reactive force field molecular dynamic simulations and density functional theory calculations was employed to investigate the CO oxidation reaction catalyzed by CuMnO_x. We examined the effect of three factors (oxygen content of CuMnO_x catalyst, pressure, and free O₂ concentration) on enhancing the CO conversion. The CuMnO₄ catalyst exhibited superior performance in the CO oxidation reaction. The main oxygen source of the oxidation product (CO₂) was found to be the lattice oxygen atoms of the CuMnO_x catalyst. The energy barrier of the oxidation reaction between CO and the lattice oxygens was relatively low, showing that this reaction was kinetically favored. The present results provide microscopic insight into the CO oxidation reaction catalyzed by CuMnO_x, which is expected to elucidate the corresponding mechanism and thus guide the design of highly active catalysts.

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