Synthesis and Hydrogen Sorption Properties of Carborane Based Metal−Organic Framework Materials

The synthesis and hydrogen uptake properties of metal−organic framework (MOFs) materials based on carboranes have been investigated. These are the first MOFs to make use of boron-rich components as building blocksspecifically, the deprotonated form of 1,12-dihydroxycarbonyl-1,12-dicarba-closo-dodecaborane. In evacuated form the initially obtained compound, featuring zinc-coordinated solvent molecules, displays modest H2 uptake at 77 K and 1 atm. Upon removal of the coordinated solvent, however, the uptake triples (2.1 wt. %), the heat of adsorption substantially increases, and the structure adjusts such that the pore size decreases.