The influence of different functional groups on enhancing CO2 capture in metal-organic framework adsorbents

Background: Among various technically and economically viable techniques for carbon capture and storage, the utilization of advanced porous materials in an adsorption process emerges as a particularly promising strategy to mitigate CO2 emissions. Metal-organic frameworks (MOFs) have exhibited exceptional potential in capturing carbon dioxide due to their intrinsic characteristics, including high surface area, permanent porosity, and impressive pore volume. To enhance the CO2 adsorption uptake in MOF materials, interior modifications of pores or surface functionalization with diverse functional groups, such as methyl, azide, amine, amide, hydroxyl, sulfide, and alkali metals are regarded as highly effective procedures. Methods: The objective of this paper is to offer a comprehensive review of various functional groups employed in ligand functionalization and their impact on improving carbon capture specifications in MOF materials. Additionally, the effects of alkali and alkaline earth metal incorporation inside MOF structures will be briefly reviewed. In the end, different proposed mechanisms for CO2 adsorption on pristine and functionalized MOFs are investigated. Significant Findings: According to the findings, MOFs modified by amine functional groups are considered as promising candidates for improving CO2 capture. This review provides valuable insights into selecting functional groups for MOF modification with higher capability in CO2 adsorption and separation.