Preparation of metal–organic framework nanosheets with electron‐rich groups for SO ₂ adsorption

Abstract Metal–organic frameworks (MOFs), as a new type of porous crystalline materials, hold great promise for gas purification in electrical insulation equipment, especially for the selective capture of SO 2 produced from the decomposition of SF 6 . However, challenges remain in the design and synthesis of MOF‐based adsorbents with salient SO 2 adsorption performance due to the limited effective interactions with SO 2 molecules. This study reports the successful direct synthesis of two‐dimensional (2D) MOFs nanosheets coordinated by Zr 4+ and tridentate carboxylic organic ligands with nitrogen‐containing electron‐rich groups within the organic ligands. The resulting MOF nanosheets exhibit enhanced interactions with SO 2 molecules due to the spatial location and electronic properties of the nitrogen groups, thereby conducing to the adsorption of SO 2 . Additionally, by precisely controlling the positioning of nitrogen groups, the Zr‐BTB‐NH 2 (BTB‐NH 2 : 1,1′:3′,1″‐Terphenyl]‐4,4″‐dicarboxylic acid, 3,3″‐diamino‐5′‐(3‐amino‐4‐carboxyphenyl) and Zr‐TPY (TPY: 4′‐(4‐carboxyphenyl)‐[2,2′:6′,2″‐terpyridine]‐5,5″‐dicarboxylic acid) MOFs synthesised in this study achieve differentiated SO 2 adsorption capacities of 39.3 cm³·g⁻ 1 and 66.3 cm³·g⁻ 1 , respectively, surpassing those of several previously reported MOFs. This strategy provides a novel design strategy for developing efficient SO 2 absorbents and lays a foundation for the further development of absorbents promising for gas remediation in electrical insulation equipment.