The methanation of CO₂ via the Sabatier process is gaining interest for power-to-gas (P2G) application. In this work, CO₂ methanation activity and stability were investigated over Ni/GDC (gadolinium-doped-ceria) catalysts at atmospheric pressure varying reaction temperature (T_SET = 300–600 °C) and space velocity (GHSV = 10,000–50,000 h⁻¹). Powder catalysts with different Ni content (15–50 wt.%) were synthesized by the solution combustion synthesis (SCS). The same method was adopted to in situ deposit the Ni/GDC (50 wt.%Ni) coating layer on the cordierite monolith (500 cpsi). The catalysts were characterized by N₂ adsorption-desorption, X-ray diffraction (XRD), H₂ temperature programmed reduction (H₂-TPR), CO₂ temperature programmed desorption (CO₂-TPD), X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM) and scanning electron microscopy (SEM). Temperature profiles along the structured catalytic bed were discussed to interpret the experimental results.

Catalytic performance increased by increasing the Ni content due to enhanced metal-to-support interaction, basicity and oxygen vacancies. Uniform, thin and high-resistance catalytic layers were in situ deposited on the cordierite monoliths by the fully reproducible SCS method. Structured catalysts showed high methane productivity per unit weight of catalyst due to simultaneous low catalytic loading and high flow rate. Excellent stability was observed over 200 h of time-on-stream. The results reported in this manuscript pinpointed on the important aspects of realizing CO₂ methanation on structured catalysts, providing a platform for further optimization studies.

通过Sabatier工艺进行的CO ₂甲烷化在功率燃气（P2G）应用中引起了人们的兴趣。在这项工作中，研究了在大气压力变化的反应温度（T _SET  = 300–600°C）和空速（GHSV = 10,000–50,000 h ）下，Ni / GDC（ga掺杂二氧化铈）催化剂对CO ₂甲烷化活性和稳定性的影响。^-1）。通过固溶燃烧合成法（SCS）合成了具有不同镍含量（15-50 wt。％）的粉末催化剂。采用相同的方法在堇青石整料（500cpsi）上原位沉积Ni / GDC（50wt。％Ni）涂层。催化剂通过N ₂吸附-解吸，X射线衍射（XRD），H ₂表征。程序升温还原（H ₂ -TPR），CO ₂程序升温脱附（CO ₂ -TPD），X射线光电子能谱（XPS），透射电子显微镜（TEM）和扫描电子显微镜（SEM）。讨论了沿着结构化催化床的温度分布，以解释实验结果。

由于增强的金属与载体之间的相互作用，碱度和氧空位，增加了镍含量，从而提高了催化性能。通过完全可重复的SCS方法将均匀，薄而高电阻的催化层原位沉积在堇青石整料上。由于同时低的催化剂负载和高的流速，结构化催化剂显示出每单位重量催化剂高的甲烷生产率。在运行时间超过200小时的过程中，观察到了极好的稳定性。该手稿中报道的结果指出了在结构化催化剂上实现CO ₂甲烷化的重要方面，为进一步优化研究提供了平台。