Enhancement of Hydrothermal Stability and CO₂ Adsorption of Mg-MOF-74/MCF Composites

High Resolution Image Download MS PowerPoint Slide Hierarchical porous composite Mg-MOF-74/MCFs were successfully synthesized using a simple and facile method under in situ solvothermal conditions. Textural structures and morphologies of the composites were characterized by X-ray diffraction (XRD), N 2 adsorption–desorption isotherms, and scanning electron microscopy (SEM), transmission electron microscopy (TEM), and thermogravimetric analysis (TGA). The results demonstrate that a large amount of nanosized Mg-MOF-74 particles is incorporated into the pores of mesocellular siliceous foams (MCFs) without remarkable aggregation and the composites possess microporous and mesoporous characteristics of both components. In addition, CO 2 adsorption properties of the composites were tested in a fixed bed with/without hydrothermal treatment. The total CO 2 adsorption capacities were calculated by breakthrough curves. The CO 2 adsorption capacity of the composites reaches 1.68 mmol/g, which is smaller than that of pristine Mg-MOF-74. However, the total CO 2 adsorption capacity of the composites after hydrothermal treatment reaches 2.66 mmol/g, which is larger than that of Mg-MOF-74 (2.39 mmol/g) under the same condition. XRD patterns and SEM images of the composites demonstrate that the hydrothermal stability and CO 2 adsorption performance of the composites were improved compared with those of pristine Mg-MOF-74 after hydrothermal treatment.