ALUMINIUM-BASED METAL–ORGANIC FRAMEWORK 53 COORDINATED WITH MANGANESE FOR CARBON CAPTURE

Advanced adsorbents for carbon capture applications are becoming more and more popular due to the pressing demand for effective materials to address rising carbon dioxide (CO₂) impacts. This study investigates the development and characterization of a bimetallic aluminium/manganese-based metal–organic framework for carbon capture. The framework was designed with varying ratios of manganese, with various reaction times and temperatures. Comprehensive characterization included Brunauer–Emmett–Teller (BET) surface area analysis, scanning electron microscopy (SEM), X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), X-ray fluorescence (XRF), and thermogravimetric analysis (TGA). The BET measurements are expected to predict textural properties that reveal higher surface areas for samples under moderate conditions and lower Mn/Al ratios, while SEM analysis is expected to reveal morphological analysis, well-defined MOF crystals with increasing Mn/Al altering particle size and surface texture; excessive manganese might lead to aggregation. XRD is expected to confirm MOF-53's crystalline structure and successful manganese integration, while XRF is expected to present a high concentration of Al and Mn oxides. The FTIR spectra should display characteristic bands for the framework and the organic linker, with possible shifts or the broadening of Al–O and Mn–O bands at higher Mn concentrations. TGA is expected to show good thermal stability at temperatures up to 250°C but may show reduced stability at high Mn/Al ratios. Al/Mn-MOF-53 synthesized at 100°C for 48 hours with a Mn/Al ratio of 0.2 is expected to have the highest CO₂ uptake through sorption measurements. Overall, the characterization results are anticipated to evidently demonstrate the influence of manganese content and process conditions on framework integrity and performance, confirming that lower manganese incorporation and moderate synthesis parameters yield materials best suited for carbon capture due to their stability, maximized surface area, and accessible pore structure.