Solvent-Treated Zirconium-Based Nanoporous UiO-66 Metal-Organic Frameworks for Enhanced CO2 Capture

Metal-organic framework (MOF)-derivednanoscale porous materialsare widely deployed in carbon capture, but the CO2 capacityis varied by different post-treatments, and its mechanism is stillunclear. Herein, we prepared UiO-66 and treated it with methanol solventand thermal activation approaches, which showed similar to 3 times enhancedCO(2) capacities from 15.1 to 45.0 mg/g and excellent recyclabilityof 10 cycles. The methanol treatment efficiently removes the residualguest molecules, including N,N-dimethylformamide,dangling organic linkers, and their derivatives, in the micropores(similar to 0.8 nm) of UiO-66 and improves the surface area, pore volume,and void fraction to enhance the CO2 capacity close tothe ideal UiO-66 materials. The molecular dynamics simulation alsoproved a good linear relationship between the surface areas, voidfraction, and CO2 capacity. This work provides a deep understandingof the MOF's activation mechanism and its applications in CO2 capture.

Automated summary

It is found that treating UiO-66 with methanol solvent and thermal activation can significantly enhance its CO2 adsorption capacity. Methanol treatment effectively removes residual impurities in the micropores of UiO-66 and improves its surface area, pore volume, and void fraction, leading to a close-to-ideal CO2 adsorption capacity.