Cobalt-Doped MnO₂ Nanofibers for Enhanced Propane Oxidation

We develop a host–guest strategy to construct cobalt-doped MnO2 nanofibers with dual reactive sites, which exhibit high activity for propane deep oxidation. After the incorporation of cobalt (the actual molar ratio of Co/Mn up to 0.15), no distinct changes of crystal structure and morphology of MnO2 nanofibers were observed, as evidenced by X-ray diffraction and transmission electron microscopy. The optimized MnCo0.2 nanofibers possessed the advantages of Mn and Co and exhibited the propane conversion of 50% (T50) and 90% (T90) at 205 and 223 °C, respectively. The Co-related species is more responsible for reducing the light-off temperature (T50), whereas the Mn-related species helps more to decrease complete oxidation temperature (T90). Furthermore, the in situ diffuse reflectance infrared Fourier transform spectroscopy results revealed the roles of Co-related species and Mn-related species during propane adsorption and oxidation. The finding demonstrates the win-win effect of two active oxides and provides a solution for developing highly efficient propane oxidation catalysts.