Topology-driven design of an ultraporous red MOF for high-performance hydrogen storage

The development of new topological metal–organic frameworks (MOFs) with ultrahigh porosity and tunable architectures is essential for advancing gas storage technologies. Simultaneously, MOFs showing high porosity typically suffer from low mechanical and chemical stability. We present here the synthesis of CU-6-M (M = Fe or Cr), a novel ultraporous MOF featuring an unprecedented red topology and interconnected hierarchical pore cavities. CU-6-Fe and Cr exhibit exceptional gravimetric Brunauer–Emmett–Teller (BET) areas as high as 7,144 m2 g-1. This unique topological framework enables them to deliver record-high total gravimetric hydrogen uptakes (up to 17 wt.%) and excellent volumetric capacity (up to 45.6 g L-1), surpassing the U.S. Department of Energy (DOE) 2025 target. Under practical temperature–pressure swing conditions (77 K, 100 bar → 160 K, 5 bar), CU-6-M achieves gravimetric and volumetric deliverable capacities up to 15.5 wt.% and 44.3 g L⁻¹, respectively. Furthermore, CU-6-Cr shows exceptional stability in air, highlighting its potential for on-board hydrogen storage applications. A comprehensive structure–property analysis, uncovered through molecular simulations, provides deep insights into topology-enhanced energy storage.