Structural resolution and mechanistic insight into hydrogen adsorption in flexible ZIF-7.

Flexible metal-organic frameworks offer a route towards high useable hydrogen storage capacities with minimal swings in pressure and temperature step-shaped adsorption and desorption profiles. Yet, the understanding of hydrogen-induced flexibility in candidate storage materials remains incomplete. Here, we investigate the hydrogen storage properties of a quintessential flexible metal-organic framework, ZIF-7.

Surviving Under Pressure: The Role of Solvent, Crystal Size, and Morphology During Pelletization of Metal-Organic Frameworks.

As metal-organic frameworks (MOFs) gain traction for applications, such as hydrogen storage, it is essential to form the as-synthesized powder materials into shaped bodies with high packing densities to maximize their volumetric performance. Mechanical compaction, which involves compressing the materials at high pressure, has been reported to yield high monolith density but often results in a significant loss in accessible porosity. Herein, we sought to systematically control (1) crystal size, (2) solvation, and (3) compacting pressure in the pelletization process to achieve high packing density without compromising the porosity that makes MOFs functional.

Boron Trifluoride Gas Adsorption in Metal-Organic Frameworks.

Coordinatively unsaturated metal-organic frameworks (MOFs) were studied for boron trifluoride (BF) sorption. MOF-74-Mg, MOF-74-Mn, and MOF-74-Co show high initial uptake (below 6.7 × 10 bar) with negligible deliverable capacity.

Phosphine Gas Adsorption in a Series of Metal-Organic Frameworks.

For the first time, phosphine adsorption has been evaluated in a series of metal-organic frameworks (MOFs). Open-metal coordination sites were found to significantly enhance the ability of MOFs to adsorb highly toxic phosphine gas, with the identity of the open-metal site also modulating the amount of gas adsorbed. The MOFs studied outperform activated carbon, a commonly used material to capture phosphine.