Synergistic Promotion of Ni/La ₂ O ₃ Catalysts by Copper for Efficient Dry Reforming of Methane

ABSTRACT The catalytic performance of Ni/La 2 O 3 and Ni–Cu/La 2 O 3 for dry reforming of methane (DRM) was investigated, focusing on reducibility, stability, and coke resistance. Cu incorporation lowered the Ni reduction temperature, as revealed by temperature‐programmed reduction (TPR), enhancing hydrogen spillover and oxygen vacancy formation. X‐ray photoelectron spectroscopy (XPS) confirms that Cu stabilizes the oxygen lattice, minimizes carbonate accumulation, and facilitates CO 2 activation. Catalytic tests at 850°C demonstrated 78% CH 4 conversion and 96% CO 2 conversion for Ni–Cu/La 2 O 3 , compared to 55% and 72% for Ni/La 2 O 3 , respectively. X‐ray diffraction (XRD) and field emission scanning electron microscopy (FESEM) confirmed that Cu prevents Ni sintering, maintaining high dispersion. Carbon deposition analysis showed 0.50 wt.% total carbon for Ni–Cu/La 2 O 3 , slightly higher than Ni/La 2 O 3 (0.42 wt.%), but with a 40% reduction in graphitic carbon. The synergistic effect between Cu and Ni optimizes Ni dispersion, modulates electronic properties, and weakens Ni–La 2 O 3 interactions, improving CH 4 activation and carbon removal. Ni–Cu/La 2 O 3 exhibits outstanding activity and resistance to deactivation, making it a highly effective and stable catalyst for CO 2 conversion and syngas production in DRM, with a strong synergy between Ni and Cu, along with the stabilizing influence of the La 2 O 3 support, enhancing its overall performance and durability.