The highly ordered and designable properties of MOFs make them competitive precursors to constructing high-performance catalysts for CO₂ methanation, however, only a few studies have investigated the facilitation effect of promoters. Herein, a series of carbon encapsulated NiFe alloy nanoparticles core-shell catalysts (Ni_xFe@C, x refers to the ratio of Ni to Fe) were successfully prepared by a method of pyrolyzing Ni-MOF-74 after impregnation in Fe³⁺ solution for CO₂ hydrogenation to CH₄, and their composition and structural characteristics were explored in detail by PXRD, N₂ adsorption/desorption measurements, TEM, and XPS, etc. Fe-doped catalysts exhibited significantly enhanced CO₂ methanation activity compared to the monometallic Ni catalysts, especially Ni₇Fe@C, which reached 72.3 % CO₂ conversion with CH₄ selectivity of 99.3 % at 350 °C, and showed a CO₂ conversion of 53.3 % at 300 °C, twice that of Ni@C. The specific effects of the Fe addition on the composition and structure of the catalysts were also investigated via a combination of experiments and DFT calculations, which indicates that appropriate incorporation of Fe was conducive to promoting the dispersion of metal particles and the adsorption ability of CO₂ and CO, and thus resulted in significantly improved catalytic performance. This work provides a promising route for the rational design of MOF-derived CO₂ methanation catalysts and makes a new attempt to investigate the influence of promoters.

MOFs高度有序和可设计的特性使其成为构建高性能CO ₂甲烷化催化剂的竞争前体，然而，只有少数研究调查了促进剂的促进作用。^{本文采用Ni-MOF-74浸渍Fe 3+}后热解的方法，成功制备了一系列碳包覆NiFe合金纳米粒子核壳催化剂（Ni _x Fe@C，x为Ni与Fe的比值）。CO ₂加氢制CH _{4溶液，并通过PXRD、N 2}对其组成和结构特征进行了详细探讨与单金属 Ni 催化剂相比，Fe 掺杂催化剂的 CO ₂甲烷化活性显着提高，尤其是 Ni _{7 Fe@C，其 CO 2}转化率为 72.3 % ，CH ₄选择性为 99.3 % 在 350 °C 下，CO ₂转化率在 300 °C 下为 53.3 %，是 Ni@C 的两倍。还结合实验和DFT计算研究了Fe的加入对催化剂组成和结构的具体影响，表明适当的Fe掺入有利于促进金属颗粒的分散和CO _{2的吸附能力。}和 CO，从而显着提高了催化性能。_{该工作为MOF衍生CO 2}甲烷化催化剂的合理设计提供了一条有前景的途径，并为研究促进剂的影响提供了新的尝试。