Electrochemical Synthesis of Metal‐Organic Frameworks Based on Zinc(II) and Mixed Ligands Benzene‐1,4‐Dicarboxylate (BDC) and 4,4′‐Bipyridine (Bpy) and its Preliminary Study on CO2 Adsorption Capacities

AbstractEfficient and environmentally friendly synthesis methods for metal‐organic frameworks (MOFs) have emerged as a compelling topic in the organometallic field. In this study, we successfully electro‐synthesized a MOF based on mixed ligands, benzene‐1,4‐dicarboxylate (BDC) and 4,4′‐bipyridine (Bpy), denoted as MOF‐508b, and investigated its CO2 adsorption capacity, comparing it with that of Zn‐BDC and Zn‐Bpy coordination polymers. Unlike the circular shapes of Zn‐BDC and Zn‐Bpy, MOF‐508 adopts a three‐dimensional structure upon binding with the pillar ligand, featuring mesoporous pore sizes. MOF‐508b demonstrates superior stability at room temperature, exhibiting a thermal stability of 400 °C. The CO2 capture potential of the materials was assessed under low‐pressure conditions at room temperature. The pillared layer of MOF‐508b results in the reduction of open metal sites, facilitating the binding of active CO2 through coordination, thereby influencing its optimum CO2 adsorption capacity (2.51 mmol g−1), which was found to be lower than that of Zn‐Bpy (3.83 mmol g−1) and Zn‐BDC (4.46 mmol g−1). The adsorption mechanism on MOF‐508b follows the Weber‐Morris model, emphasizing diffusion within particles over direct attachment to the material surface.