Abstract
Metal-Organic Frameworks (MOFs) represent a promising class of porous materials for carbon capture due to their high surface area, tunable pore structure, and chemical versatility. However, optimizing their intrinsic CO2 adsorption capacity and selectivity often requires further refinement. This study investigates the impact of post-synthetic modification (PSM) on the CO2 adsorption performance of a robust zirconium-based MOF, UiO-66. Specifically, we employed amine grafting techniques using diethylenetriamine (DETA) to introduce basic sites within the MOF pores. The modified materials were thoroughly characterized using X-ray diffraction, nitrogen physisorption, Fourier-transform infrared spectroscopy, and thermogravimetric analysis, confirming the successful incorporation of amine groups while retaining the structural integrity. CO2 adsorption isotherms measured at 298 K demonstrated a significant enhancement in CO2 uptake, particularly at low pressures, for the amine-functionalized UiO-66 compared to the pristine MOF. This improvement is attributed to the increased interaction between the acidic CO2 molecules and the basic amine sites. Our findings highlight PSM as an effective strategy for tailoring MOF properties, offering a viable pathway towards developing more efficient adsorbents for carbon capture applications.
