A computational approach towards understanding hydrogen gas adsorption in Co-MIL-88AElectronic supplementary information (ESI) available: The charge density difference for H2 at the hollow site, the electronic density of state of H2 and the μ3-O atoms, the density of adsorbed hydrogen molecules, the vibrational frequency of the adsorbed H2, the contribution of the electrostatic interaction with respect to the dispersion one, the average distance of H2 molecule and the nearest atoms, and the stru

• Main Authors: Xuan Huynh, Nguyen Thi, Na, O My, Chihaia, Viorel, Son, Do Ngoc
• Format: Journal Article
• Language: English
• Published: 14.08.2017
• ISSN: 2046-2069
• DOI: 10.1039/c7ra05801b

Unsaturated metal centers in metal-organic framework MIL-88A are able to significantly enhance the amount of gas adsorbed at ambient temperatures and low pressures. This material has been investigated for various applications; however, it has not yet been tested for hydrogen storage. In this research, we examined the interaction of hydrogen gas (H 2 ) with Co-MIL-88A by using the van der Waals dispersion-corrected density functional theory calculations. The H 2 molecule was found to adsorb most favorably at the hollow site of the metal trimers in Co-MIL-88A because of the maximum overlap between the bonding state of the H 2 molecule and the total density of state of the Co-MIL-88A. In addition, the hydrogen adsorption isotherms were also assessed by grand canonical Monte Carlo simulations. The results showed that Co-MIL-88A is one of the most effective H 2 storage materials. The hydrogen adsorption is most favorable at the hollow site of Co-MIL-88A.