The dependence of the catalytic activity and coke resistance of Ni-based catalysts on the support type was investigated in the dry reforming of methane (DRM). Catalysts were prepared using incipient wetness impregnation and analyzed using ICP-OES, BET-BJH, XRD, H₂-chemisorption, H₂-TPR, and CO₂-TPD. DRM was performed at 600–750 °C at 144,000 mL/g_cat∙h of GHSV (CH₄/CO₂/N₂ = 1/1/1). Ni/Al₂O₃ and Ni/MgO catalysts formed NiAl₂O₄ and NiO-MgO solid solutions, respectively, owing to strong binding between the metal and support. In contrast, MgO-Al₂O₃ and MgAl₂O₄ supports suppressed NiAl₂O₄ and NiO-MgO solid solution formation, due to Mg addition, with high metal dispersions of 4.6 and 6.6%, respectively. In the DRM reaction, the Ni/MgO-Al₂O₃ and Ni/MgAl₂O₄ catalysts showed high CH₄ conversions of 78.1 and 76.8%, respectively, compared with Ni/Al₂O₃ and Ni/MgO at 750 °C. A stability test was performed at 600 °C for 20 h. A coke study of the spent catalysts was performed using SEM and TGA. Alkaline-earth metal-containing catalysts Ni/MgO-Al₂O₃ and Ni/MgAl₂O₄ with strong CO₂ adsorption properties showed 20 wt% reduction in carbon deposition compared to commercial catalysts. Therefore, the support and basic properties of the catalyst significantly influenced the catalyst performance and coke resistance in the DRM.

Ni/zeolite 13X catalyst synthesized by deposition–precipitation exhibits improved low-temperature performance for NH₃ decomposition owing to high dispersion and uniform deposition of active Ni on the surface and in the pores of the zeolite support.

Herein, a B₅‐site‐rich Ru/MgAl₂O₄ nanocatalyst for the production of CO_x‐free hydrogen from ammonia (NH₃) is synthesized using the polyol method. The polyol method enables size‐sensitive Ru‐nanoparticle growth and controlled B₅‐site formation on the catalyst by tuning the carbon‐chain length of the polyol solvent used, obviating the use of a separate stabilizer and enhancing electron donation from Ru (with a high surface electron density) and π‐back bonding. The Ru/MgAl₂O₄ (BG) catalyst synthesized using butylene glycol (a long‐carbon‐chain solvent) contains 2.5 nm Ru particles uniformly dispersed on its surface and abundant B₅ sites at (0 0 2)/(0 1 1). Moreover, the Ru/MgAl₂O₄ (BG) catalyst exhibits lower activation energy (48.9 kJ mol⁻¹) and higher H₂ formation rate (565–1,236 mmol g_cat⁻¹ h⁻¹ at 350−450 °C and a weight hourly space velocity of 30,000 mL g_cat⁻¹ h⁻¹) during the NH₃ decomposition reaction than catalysts with a similar Ru particle size and high metal dispersion synthesized by the impregnation and deposition–precipitation methods. This high performance is possibly because the abundant electron‐donating B₅ sites on the catalyst surface accelerate the recombination–desorption of N₂, which is the rate‐determining step of the NH₃ decomposition reaction at low temperatures. Thus, this study facilitates clean hydrogen production.