Tailoring Ni‐MOFs by Microwave‐Assisted Synthesis for Efficient CO 2 Methanation

ABSTRACT Ni‐containing metal–organic frameworks (MOFs) have emerged as promising precursors for CO 2 hydrogenation due to their tunable structural properties. In this work, Ni‐MOFs were synthesized by a microwave‐assisted solvothermal method using 2‐methylimidazole as the organic ligand. The materials were characterized by x‐ray diffraction, thermogravimetric analysis (TGA), Raman and infrared spectroscopy, scanning electron microscopy (SEM), N 2 adsorption–desorption, and CO 2 temperature‐programmed desorption. The results showed that longer synthesis times promoted higher crystallinity, lower defect density, and improved structural organization. Microwave‐assisted synthesis also favored the formation of more homogeneous structures, directly influencing the properties of the derived catalysts after thermal decomposition and reduction. Catalytic evaluation revealed that the catalyst derived from the more organized MOF achieved the highest CO 2 conversion (>60%), producing both CO and CH 4 . In contrast, the catalyst derived from the less organized MOF exhibited lower CO 2 conversion but higher selectivity toward CH 4 . These results demonstrate that microwave‐assisted synthesis is an effective strategy for tuning the structural properties of Ni‐MOF precursors and controlling the catalytic behavior of the derived materials in CO 2 methanation.