Regulating porous liquids properties via mixed-ligands strategy for CO₂ capture

Addressing global warming and advancing carbon neutrality, efficient Carbon Capture, Utilization and Storage (CCUS) is pivotal, with carbon capture as its critical first step. Porous solid materials, despite their high adsorption capacity, face limitations in continuous industrial application due to poor cyclic utilization and integration with fluid transport systems. Porous Liquids (PLs), emerging as a solution by merging solid porosity with liquid fluidity, combine selective sorption with processability but remain constrained by component-dependent property control, lacking precise tuning of porous hosts. This study introduces a mixed-ligand strategy to engineer PLs via surface functionalization of porous hosts. By using UiO-66-OH, we modulated surface -OH content by adjusting BDC/BDC-OH ligands ratios during synthesis, followed by grafting KH560 and M2070 to fabricate PLs. Increasing -OH content enabled progressive polymer grafting, transitioning solids to liquids with tunable viscosity. The resulting PLs exhibited enhanced CO₂ sorption and selectivity for CO₂/CH₄ and CO₂/N₂ separation. This approach achieves precise PL customization, aligning material properties with industrial needs and advancing PLs applications in carbon capture, and provides a foundation for tailored PLs design, bridging fundamental research to practical decarbonization technologies.