Tricking Inert Metals into Water-Absorbing MOFs

In a recent issue of Chem, Towsif Abtab et al. describe a Cr³⁺-based metal-organic framework (MOF) that can capture a record-shattering 200% of its weight in water. Remarkably, whereas the Fe³⁺ and Al³⁺ variants of the framework collapse upon water exposure, the Cr³⁺ version shows no decline in crystallinity or capacity after 100 cycles of water uptake. Synthesized via a cation exchange process of Cr²⁺ for Fe³⁺, the achievement of the highly porous Cr³⁺ structure points the way toward additional MOF topologies with exceptional stability enabled by inert metals. In a recent issue of Chem, Towsif Abtab et al. describe a Cr³⁺-based metal-organic framework (MOF) that can capture a record-shattering 200% of its weight in water. Remarkably, whereas the Fe³⁺ and Al³⁺ variants of the framework collapse upon water exposure, the Cr³⁺ version shows no decline in crystallinity or capacity after 100 cycles of water uptake. Synthesized via a cation exchange process of Cr²⁺ for Fe³⁺, the achievement of the highly porous Cr³⁺ structure points the way toward additional MOF topologies with exceptional stability enabled by inert metals.