Fe-doped MnO₂ as an efficient catalyst for low temperature propane oxidation

Manganese oxides were received extensive attention on account of its low cost, variable valence state and excellent redox properties. Herein, we successfully prepared various Fe-doped MnO₂ catalysts to further improve the catalytic activity of MnO₂ on propane. Physicochemical characterization results displayed that with the increase of Fe doping amounts, the crystalline phase of MnO₂ gradually changed from α-MnO₂ and β-MnO₂ to Fe₂O₃, the particle size of catalysts decreased and the specific surface area increased. However, increasing the content of Fe could not monotonically enhance the catalytic performance of catalysts on propane. When the molar ratio of Fe/Mn was 0.25, the largest amount of Mn⁴⁺ species and lattice oxygen species were exposed on the surface of Mn8Fe2, and showed the best low temperature reducibility, which was ascribed to the synergistic effect between Mn and Fe was enhanced. It presented optimal catalytic activity for propane oxidation with temperature of propane conversion at 90% (T₉₀) as low as 279 °C under 0.1% propane and 5% O₂. This work provided a new way to design and synthesize efficient non-noble metal catalysts for the elimination of propane, which had certain application value.