Discovery of a Robust Ru 1 –O–Ce Single Atom Catalyst for Coke-Free Dry Reforming of Methane

Dry reforming of methane (DRM) represents a key route for CO 2 utilization and methane valorization, yet catalyst coking and sintering under harsh conditions limits its large-scale application. Here, we discover a single-atom catalyst featuring Ru 1 –O–Ce sites that operates stably for DRM over 600 h at 40–225 L g cat –1 h –1 without detectable coking. Further anchoring Ru 1 –O–Ce sites on commercial particulate Al 2 O 3 enables 2000-h catalytic stability at 750 °C, with CH 4 /CO 2 conversions approaching thermodynamic equilibrium. Mechanistic studies reveal that Ru 1 –O–Ce sites partially dissociate methane at Ru 1, and CH x species react with nearby O atoms to form CH x O intermediates; CO 2 is efficiently activated at formed oxygen vacancies to restore Ru 1 –O–Ce sites. This bifunctional behavior aligns CH 4 and CO 2 activation, ensuring coke-free DRM progression and opening new avenues for designing stable, effective single-atom catalysts for methane reforming.