Fine-Tuning a Robust Metal–Organic Framework toward Enhanced Clean Energy Gas Storage

The development of adsorbents with molecular precision offers a promising strategy to enhance storage of hydrogen and methaneconsidered the fuel of the future and a transitional fuel, respectivelyand to realize a carbon-neutral energy cycle. Herein we employ a postsynthetic modification strategy on a robust metal–organic framework (MOF), MFU-4l, to boost its storage capacity toward these clean energy gases. MFU-4l-Li displays one of the best volumetric deliverable hydrogen capacities of 50.2 g L–1 under combined temperature and pressure swing conditions (77 K/100 bar → 160 K/5 bar) while maintaining a moderately high gravimetric capacity of 9.4 wt %. Moreover, MFU-4l-Li demonstrates impressive methane storage performance with a 5–100 bar usable capacity of 251 cm3 (STP) cm–3 (0.38 g g–1) and 220 cm3 (STP) cm–3 (0.30 g g–1) at 270 and 296 K, respectively. Notably, these hydrogen and methane storage capacities are significantly improved compared to those of its isoreticular analogue, MFU-4l, and place MFU-4l-Li among the best MOF-based materials for this application.