Facile synthesis of a CuMnOx catalyst based on a mechanochemical redox process for efficient and stable CO oxidation

Abstract

Considering the large amount of carbon monoxide produced by human activities causing serious problems to the environment, it can be seen that the low-temperature catalytic combustion of CO is a desirable route for CO removal. Herein, we reported an efficient and stable copper–manganese catalyst (CuMnO_x-MR) based on a mechanochemical redox process. Interestingly, more oxygen vacancies and lattice defects emerged in CuMnO_x-MR due to the molecular-scale redox reaction between Cu⁺ and MnO₄⁻. Meanwhile, the mechanochemical redox process was completed by solvent-free and rapid (1 h) ball milling. Moreover, the ball milling could continually break CuMnO_x-MR particles to generate a high degree of interstitial porosity (up to 59 m² g⁻¹). Compared with the control samples, CuMnO_x-MR exhibited a lower catalytic temperature (T₉₀ = 140 °C) in the CO oxidation reaction and performed well in the stability test (150 °C, 100 h). Finally, the CuMnO_x-MR showed good resistance to H₂O (4.2 vol% moisture, 100 h) and SO₂ (100 ppm), which suggests its potential for practical applications.