Low-Temperature Oxidation of Toluene over MnO-CeO Nanorod Composites with High Sinter Resistance: Dual Effect of Synergistic Interaction on Hydrocarbon Adsorption and Oxygen Activation.

Synergistic interaction derived by a heterointerface structure on the surface of metal oxide catalysts has a crucial role in improving the catalytic activity. In this work, MnO nanoparticles were dispersed on the surface of CeO nanorods to generate a MnO-CeO heterointerface structure, and its effect on toluene adsorption and catalytic oxidation performance was investigated. The results show that MnO is well dispersed on CeO nanorods, and the interaction of Mn-Ce significantly reduces the strength of the Ce-O bond and increases the conversion of Ce to Ce, which further promotes the activation of oxygen. Compared to MnO on SiO without synergistic interaction, the enhancement of toluene adsorption on this novel MnO-CeO hetero-interface structure can also make a great contribution to the improvement of the catalytic reaction process. Among them, the synergistic effect of CeO-MnO could reduce the temperature of 90% toluene conversion to 210 °C (this value is 83 °C lower than that over pure CeO nanorods). In addition, the fresh MnO-CeO catalyst not only shows excellent stability and moisture resistance but also retains highly low-temperature activity even after thermal aging at 750 °C for 100 h.