International Journal of Science, Engineering and TechnologyAuthors: Dr. Sarika Sharma
Abstract: When atmospheric carbon dioxide (CO₂) concentrations increase rapidly due to human activities, the need for scalable carbon removal technology has grown considerably. Direct Air Capture (DAC) is a successful negative emission approach which is able to remove CO₂ by extracting it from the air and cleaning molecules to its target level even in an atmosphere. However, due to very low atmospheric CO₂ concentrations (∼400 ppm) and moisture, for DAC materials to be used, high selectivity and stability are essential attributes and low regeneration energy. To improve the application of DAC in dilute environments, metal-organic frameworks (MOFs) are a new class of very porous nanomaterials whose unique chemical and structural properties have made them promising for DAC applications. Functionalized MOFs (i.e., amine-grafted materials and hybrid ultra microporous structures) exhibit improved adsorption performance and are able to capture CO₂ even in humid conditions. Recent progress of MOF-based DAC technology in solid sorbents and membranes, and the relationship of molecular structure and CO₂ capture efficiency, also contribute to this. In this review, we also discuss the best computational and machine learning approaches for rapid screening and optimization of MOFs to ensure high-performance materials from a wide range of chemical compounds. Many challenges such as moisture sensitivity, high synthesis costs, structural instability, and energy-intensive regeneration are among the critical difficulties for MOF-based DAC systems to be achieved at large scale. To eliminate such limitations, innovative design solutions such as surface functionalization as well as scalable synthesis routes with high productivity of materials, and process integration should be adopted. Nanostructured MOFs represent a new path to global decarbonization with efficient and flexible DAC systems. Further interdisciplinary research in materials science, process engineering, and techno-economic analysis will translate laboratory results into carbon capture technologies that are compatible with net-zero climate targets at the scale of commercial production.
DOI: https://zenodo.org/records/19384942
