Mn-Ni Co-Doping Stimulated the Co3O4 Catalyst for a High-Performance Propane Oxidation Catalyst

The development of advanced non-noble metal catalysts holds importance for a high-performance oxidation reaction. In this study, dual Mn- and Ni-atom-doped Co3O4 was engineered to simultaneously regulate the surface and structure of Co3O4 for enhancing the catalytic propane oxidation reaction. The incorporation of Mn increases the specific surface area, facilitates lattice distortion, and creates more active oxygens. Ni doping effectively improves the oxygen mobility and the low-temperature oxidation reactivity. Meanwhile, both Mn and Ni doping increase the acidity of the Co3O4 surface. Benefiting from the synergistic effect of Mn and Ni doping, the co-doped Mn-Ni-Co3O4 exhibits the largest amount of exposed active oxygens, highest intrinsic oxidation ability, and abundant acidic sites. Consequently, the Mn-Ni-Co3O4 catalyst achieves enhanced propane activation and catalytic oxidation activity, with an exceptional propane conversion rate of 3.5 μmol g−1 s−1 at 195 °C, which is about 3.9 times that of the original Co3O4. In addition, the Mn-Ni-Co3O4 catalyst maintains stable performance during a 30 h hydrothermal test. This work presents a Mn-Ni co-doping strategy that enables synergistic modulation of surface structure and properties, simultaneously tuning oxygen vacancy (OV) formation, surface acidity, and oxygen mobility, leading to catalytic performance superior to that of single-element-doped catalysts.