An Ab Initio Force Field for Predicting Hydrogen Storage in IRMOF Materials

Abstract

An ab initio force field that describes interactions between hydrogen molecules and IRMOF materials is proposed. The force field parameters were derived by fitting to ab initio data that includes higher-order electron correction and extended basis-set effects and validated by calculating adsorption isotherms and isosteric heats of adsorption of H2 in IRMOF-1 using GCMC simulations performed at 77 and 298 K, in a broad range of pressure from 0.0 to 8.0 MPa. Excellent agreements with experimental data were obtained. The force field was then applied to predict hydrogen-storage capacities for eight additional IRMOF materials. It was identified that the void fraction of volume (VFV) has a strong impact on the adsorption capacity, and its impacts on gravimetric and volumetric adsorption uptakes exhibit opposite trends. An overall optimal VFV is ca. 87% for IRMOFs at 77 K and 8.0 MPa.

Hydrogen storage in porous structures of adamantane-based nitrogen-heterocyclic ring with diamond-like structure

“…The performance in hydrogen storage of the porous materials can also be forecasted by the radius ( r ) which is the distances between the center of the pore in materials and the nearest H atom. Bigger radius always related to smaller density, large percent pore volume, surface area per gram ( S S1 ), and also to large gravimetric H 2 adsorption . If we consider the VDW radius of H atom (1.20 Å), the diameters of them are 17.08, 30.24, 15.46, and 23.82 Å, respectively.…”

“…We set both the equilibration and production steps up to 5 × 10 6 . The gravimetric H 2 adsorption percent and the volumetric H 2 adsorption capacity are calculated using the similar formula that mentioned by Fu and Sun . In this article, the excess adsorbed amounts ( N exc , in number.)…”

Screening of hypothetical metal–organic frameworks for H2 storage

“…26,29,30 A different attempt has been made by trying to parameterise a Lennard-Jones force field for the MOF-H 2 interaction with data from ab initio MP2 calculations. 31,32 In a similar way, Matanovic et al 33 performed rigorous quantum calculations to study the H 2 binding in porous materials with state of the art accuracy and showed the intrinsic difficulties of the subsequent GCMC simulations in reproducing the potential energy surface.…”

Effect of flowthrough cooling heat removal on the performances of MOF-5 cryo-adsorptive hydrogen reservoir for bulk storage applications

“…Hydrogen stored in these reservoirs, nevertheless, suffers from technical limitations such as low net volumetric energy density in the case of CGH 2 and fuel-loss due to liquid hydrogen boil-off in the case of LH 2 [1e3]. Adsorptive hydrogen storage on microporous metal-organic frameworks (MOFs) is a potential alternative hydrogen storage approach which could overcome the above limitations of conventional hydrogen storage technologies [4,5]. However, unlike CGH 2 approach, adsorptive hydrogen storage approach requires the hydrogen stored in the adsorbent medium to be maintained at cryogenic temperatures for attaining high volumetric storage density [6].…”