Gd–Ru Nanoparticles Supported on Zr_0.5Ce_0.5O₂ Nanorods for Dry Methane Reforming

Dry reforming of methane is considered a potential reaction for the utilization of waste greenhouse gases to generate valuable chemicals. However, catalyst deactivation under a harsh reaction condition appears as the main obstacle toward its commercialization. In the present work, a facile hydrothermal synthesis procedure was adopted to prepare a robust Ru-based catalyst. Among the various combinations, a 1% Ru supported over Zr0.5Ce0.5O2 nanorod catalyst showed enhanced coke resistance and almost stable activity during 200 h activity analysis. Promotion of Ru/Zr0.5Ce0.5O2 with an optimum amount of Gd2O3 improved catalyst stability, which was attributed to the strong interaction of Ru with Gd2O3 leading to smaller Ru particle size (∼5 nm) and an improved OSC was inhibiting coke deposition. Promotion with 0.5% Gd2O3 further lowered the apparent activation energy of methane conversion to ∼20.6 kcal/mol without changing the reaction orders significantly. DFT calculation confirmed, due to the orbital similarity, methane cracking is preferred over Ru atoms and CO2 activation occurred on Gd atoms.