Synthesis and hydrogen adsorption properties of a new iron based porous metal-organic framework

A new metal-organic framework [Fe3O(OOC-C6H4-COO)(3)(H2O)(3)]Cl center dot(H2O)(x) was synthesized with a specific surface area of 2823 m(2)/g and a lattice parameter of 88.61 angstrom. Isostructural with MIL-101, this compound exhibits similar hydrogen adsorption properties, with maximum adsorption capacity of 5.1wt.% H at 77 K. The adsorption enthalpy of hydrogen for MIL-101 and ITIM-1 (MIL-101Fe) at zero coverage was calculated for a wide temperature range of 77 K divided by 324 K, considering corrections for the variation of hydrogen gas entropy with the temperature. The resulted adsorption enthalpy is 9.4 kJ/mol for MIL-101, in excellent agreement with the value reported in literature from microcalorimetric measurements, and a value of 10.4 kJ/mol at zero coverage was obtained for ITIM-1 (MIL-101Fe). Copyright (C) 2010, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.