Benchtop <i>In Situ</i> Measurement of Full Adsorption Isotherms by NMR

Physisorption using gas or vapor probe molecules is the most common characterization technique for porous materials. The method provides textural information on adsorbent as well affinity a specific adsorbate, typically through equilibrium pressure measurements. Here, we demonstrate how low-field NMR can be used to measure full adsorption isotherms, and by selectively measuring 1H spins of adsorbed molecules, rather than those in phase, this “NMR-relaxorption” insights about local dynamics beyond what learned from physisorption alone. potential double-barreled approach was illustrated set microporous metal–organic frameworks (MOFs). For methanol ZIF-8, identifies multiple guest populations assigned MeOH clusters pore center, bound at cage windows defect sites. UiO-66(Zr), sequential filling demonstrated accurate topologies are directly obtained, MIL-53(Al), structural phase transitions accurately detected linked with two dimeric chemical species localized positions framework.