Hydrogen storage in a highly interpenetrated and partially fluorinated metal-organic framework.

A partially fluorinated metal-organic framework, Zn(bpe)(tftpa)·cyclohexanone [bpe = 1,2-bis(4-pyridyl)ethane; tftpa = tetrafluoroterephthalate], has been synthesized, and its H2 storage properties are reported. The structure is highly interpenetrated yet contains templating cyclohexanone molecules, which can be easily removed to give a porous material with fluorine atoms exposed to the pore surface. The material adsorbs 1.04 wt % H2 at 77 K and 1 atm with an adsorption enthalpy (Qst) of 6.2 kJ/mol, which represents a slight enhancement in the binding strength due to the presence of fluorine atoms over comparable metal-organic frameworks, which bind through purely physisorptive methods.