Toward hydrogen storage material in fluorinated zirconium metal-organic framework (MOF-801): A periodic density functional theory (DFT) study of fluorination and adsorption

In this study, the structural properties and hydrogen adsorption energy of the fluorinated metal-organic framework (MOF)-801 were evaluated using density functional theory (DFT). We calculated the Zr-F bond distance to be approximately 0.225 nm, which is longer than the bond distance in zirconium fluoride compounds. Due to the electronegativity of F, this site was considered as an adsorption site for hydrogen. We determined the adsorption energy to be -5 kcal/mol per hydrogen (H-2) molecule, which is higher than that of H-2 in pristine MOF. This value is also slightly lower than the adsorption energy in a metal-decorated MOF. The introduction of F atoms is determined to enhance the binding capacity of MOF-801. (C) 2020 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.