A novel Ni–MoCxOy interfacial catalyst for syngas production via the chemical looping dry reforming of methane

Abstract

<h2>Summary</h2> Modulating the oxygen-metal interface that enables efficient and selective C–H activation remains challenging. Herein, we present a novel MoC_xO_y oxygen carrier for syngas production via the chemical looping CH₄–CO₂ reforming (CL-DRM) reaction. Molybdenum carbide additive induces the re-dispersion of Ni particles from Al₂O₃ surface to α-MoC driven by the strong interaction between Ni and α-MoC. A dynamic structure transformation between MoC_x and MoC_xO_y occurs and new Ni–MoC_xO_y interfaces form during the redox cycling, which is discovered to be crucial for the low-temperature CH₄ activation using surface construction experiments and <i>in-situ</i> spectroscopic methods. As a result, Ni–(α-MoC)/Al₂O₃ exhibits near 100% selectivity to syngas with a H₂/CO ratio of 2:1 at 500°C, which is a significantly lower temperature than that of conventional systems. This study first employs molybdenum carbide as an oxygen storage material (OSM) in CL-DRM reaction, paving the way of utilizing transition metal carbides as OSMs in chemical looping processes.