Resolving the Activity–Stability Trade‐Off in Methane Dry Reforming via Ru‐Preferential CH 4 Activation on Isolated Ni–Ru Dual Sites
Jingyi Wang, Ming Li, Min Liu, Xingmin Liu, Guofei Xia, Zhan GaoABSTRACT
Dry reforming of methane, the endothermic co‐conversion of CH 4 and CO 2 into syngas (H 2 /CO), is typically limited by low‐temperature activity and carbon‐induced deactivation at high temperatures. Here, a geometrically isolated dual‐site architecture is established by co‐anchoring Ni and Ru atomic sites on defect‐rich CeO 2 . The optimized 1NiRu/CeO 2 catalyst achieves CH 4 /CO 2 conversions of 21.46%/24.10% and a H 2 /CO ratio of 0.91 at 500°C, and approaches equilibrium (86.77%/92.78%) at 750°C. 1NiRu/CeO 2 demonstrates outstanding stability over 150 h, with negligible carbon deposition compared to 1Ru/CeO 2 . Operando spectroscopy and theoretical calculations reveal preferential CH 4 activation at Ru sites in the isolated Ni‐Ru dual‐site structure. The Ru δ+ −O v −Ce 3+ interfacial sites preferentially dissociate CH 4 into CH 3 * species that are further oxidized to CH 3 O * via a low‐barrier, lattice oxygen‐mediated pathway, while Ni δ+ −O v −Ce 3+ sites readily activate CO 2 and replenish O lattice . This oxidative pathway effectively suppresses CH x deep dehydrogenation and, coupled with Ni‐driven CO 2 activation, establishes a self‐sustaining O lattice /O v redox cycle. This synergistic cycle enables a site‐selective division of labour for CH 4 /CO 2 activation, thereby maintaining coke‐resistant activity across 400°C–750°C. This work establishes a generalizable strategy for isolated dual‐site catalyst design, where Ru‐preferential CH 4 activation and vacancy‐governed interfacial cooperation orchestrate low‐temperature activity, stability, and coke resistance, enabling efficient and durable CH 4 /CO 2 valorization via dry reforming.