The influence of Ni stability, redox, and lattice oxygen capacity on catalytic hydrogen production via methane dry reforming in innovative metal oxide systems

Finding a robust catalytic system for hydrogen production via dry reforming of methane (DRM) remains a challenge. Herein, MNi_0.9Zr_1−xY_xO₃ (M = Ce, La, and La_0.6Ce_0.4; x = 0.00, 0.05, 0.07, and 0.09) catalyst was prepared by the sol–gel method, tested for DRM and characterized by surface area and porosity, X-ray diffraction, H₂-temperature programmed reduction, thermogravimetry, and transmission electron microscopy. In La_0.6Ce_0.4NiO₃ catalyst, the substitution of Ni by 0.1% Zr results in a constant high catalytic activity (83% hydrogen yield at 800°C) due to the presence of reducible “NiO-species interacted strongly with the support” (stable metallic Ni over reduced catalyst) and redox input by ceria phase for laying instant lattice oxygen during lag-off period of CO₂. Substitution of Ni by Zr and Y in the CeNiO₃ catalyst system nurtures Ni₃Y (providing highly stable metallic Ni for CH₄ decomposition) and cerium yttrium oxide phases (providing strong redox input). CeNi_0.9Zr_0.01Y_0.09O₃ shows 85% H₂ yield at 800°C.