Facilitating the dry reforming of methane with interfacial synergistic catalysis in an Ir@CeO_2-x catalyst.

Abstract

The dry reforming of methane provides an attractive route to convert greenhouse gases (CH₄ and CO₂) into valuable syngas, so as to resolve the carbon cycle and environmental issues. However, the development of high-performance catalysts remains a huge challenge. Herein, we report a 0.6% Ir/CeO_2-x catalyst with a metal-support interface structure which exhibits high CH₄ (~72%) and CO₂ (~82%) conversion and a CH₄ reaction rate of ~973 μmol_CH4 g_cat^-1 s^-1 which is stable over 100 h at 700 °C. The performance of the catalyst is close to the state-of-the-art in this area of research. A combination of in situ spectroscopic characterization and theoretical calculations highlight the importance of the interfacial structure as an intrinsic active center to facilitate the CH₄ dissociation (the rate-determining step) and the CH₂* oxidation to CH₂O* without coke formation, which accounts for the long-term stability. The catalyst in this work has a potential application prospect in the field of high-value utilization of carbon resources.