Facile Synthesis of MgO-Modified Carbon Adsorbents with Microwave-Assisted Methods: Effect of MgO Particles and Porosities on CO₂ Capture

In this study, magnesium oxide (MgO)-modified carbon adsorbents were fabricated using a nitrogen-enriched carbon precursor by microwave-Assisted irradiation for CO₂ capture. The X-ray diffraction (XRD) patterns showed the characteristic diffraction peaks of MgO at 43° and 62.5°, and no impurities were apparent. By changing the microwave reaction time, the spherical structure of the parent material was transformed to a hybrid structure with MgO crystalline particles in a carbon matrix. The morphology evolution and properties of the prepared materials were also investigated using transmission electron microscopy and N₂ adsorption, respectively. On optimising the conditions, the prepared sample attained a high CO₂ uptake of 1.22 mmol/g (5.3 wt.%) under flue gas conditions (15% CO₂ in N₂). It was found that MgO affected the CO₂ capture behaviour by enhancing the fundamental characteristics of the carbon surfaces.