Hydrogen Storage in a Potassium‐Ion‐Bound Metal–Organic Framework Incorporating Crown Ether Struts as Specific Cation Binding Sites

Abstract

AbstractTo develop a metal–organic framework (MOF) for hydrogen storage, SNU‐200 incorporating a 18‐crown‐6 ether moiety as a specific binding site for selected cations has been synthesized. SNU‐200 binds K+, NH4+, and methyl viologen(MV2+) through single‐crystal to single‐crystal transformations. It exhibits characteristic gas‐sorption properties depending on the bound cation. SNU‐200 activated with supercritical CO2 shows a higher isosteric heat (Qst) of H2 adsorption (7.70 kJ mol−1) than other zinc‐based MOFs. Among the cation inclusions, K+ is the best for enhancing the isosteric heat of the H2 adsorption (9.92 kJ mol−1) as a result of the accessible open metal sites on the K+ ion.