Insights into Light-Enhanced Interfacial Oxygen Migration for Highly Active Dry Reforming of Methane

Oxygen migration on catalyst surfaces is crucial for transforming two greenhouse gases (CH 4 and CO 2 ) into syngas through dry reforming of methane (DRM), as it drives key elementary reactions, generates reactive oxygen vacancies and suppresses carbon deposition. An efficient light-enhanced oxygen-migration strategy was successfully implemented with an Ir/CeO 2 photothermal catalyst in this work. Recordable photothermal catalytic production rates of 6.56 and 8.55   mol·g -1 ·h -1 for H 2 and CO have been achieved at 700 °C with a light intensity of 28   kW·m -2 . Compared with dark conditions, the yields of H 2 and CO under light exposure are increased by 106% and 57%, respectively, with the conversions of CH 4 and CO 2 reaching 50% and 64%. Furthermore, the pivotal role of the pronounced oxygen-migration-mediating capability of Ir clusters supported on CeO 2 has been unveiled by integrating theoretical calculations with a suite of in-situ characterizations. Photogenerated electrons transfer from CeO 2 to the Ir species, enhancing their ability to induce oxygen migration and generate oxygen vacancies, thereby leading to a significant increase in photothermal catalytic DRM performance. This work not only successfully developed an efficient photothermal catalyst for DRM but also proposed an innovative view to inspire the mechanism of light-enhanced catalysis based on oxygen migration.