Rationally “clicked” post-modification of a highly stable metal–organic framework and its high improvement on CO2-selective capture

Abstract

Based on the imperativeness of CO₂ capture and sequestration to reduce increasing anthropogenic CO₂ emissions, an efficient CO₂-selective sorbent, MIL-101-triazo-NH₂, was developed by grafting CO₂-philic triazole and amine groups into a highly stable mesoporous metal–organic framework, MIL-101, via click chemistry. Compared to pristine MIL-101, MIL-101-triazo-NH₂ exhibits a remarkably improved CO₂ uptake capability up to 128.3 cm³ g⁻¹ (20.1 wt%) at 1 atm and 273 K, and a significantly enhanced selectivity towards CO₂ over N₂. The improved performance of MIL-101-triazo-NH₂ on both the CO₂ uptake capability and selectivity demonstrates that the construction of analogues of solution-based absorbents through “clicked” post-modification of porous materials could be a reliable strategy for the fabrication of CO₂-selective solid adsorbents with optimized separation efficiency and easy regeneration ability.