Enhancement of Hydrogen Adsorption in Metal−Organic Frameworks by Mg²⁺ Functionalization: A Multiscale Computational Study

Abstract

By means of multiscale theoretical techniques, we examined the ability of Mg 2+ to enhance H 2 storage in metal-organic frameworks. Ab initio calculations showed that Mg 2+ increases more than five times the interaction energy between the hydrogen molecules and the new proposed organic linker of the IRMOF-10, reaching the value of 4.73 kcal/mol. The substituted group of the linker may host up to five hydrogen molecules with an average interaction energy of 3.1 kcal/mol per H 2 molecule. GCMC atomistic simulations verified that the proposed material can be qualified among the highest adsorbing materials for volumetric storage of H 2 , especially under ambient conditions. This functionalization strategy can be applied in many different framework structures to enhance their gas storage abilities.

Effect of modified linkers of MOF-5 on enhancing interaction energies: A theoretical study

“…However, so far there is no binding energy results available in literature to validate our calculations except for unmodified linker, benzene dicarboxalate mentioned above. Our investigation is in agreement with previous studies that showed modification of MOFs models increases the interaction energies between hydrogen molecule and MOFs[11,25,[37][38][39][40][41] . From the investigations it can be concluded that using density functional theory based on PW91/DN level (GGA functional) and M06-2X methods is reliable for accurate H 2 binding energies on the models of modified linkers.Table3.…”

Hydrogen Production and Its Storage from Solar Energy

“…In general, hydrogen can be stored in different forms [5]. The possible approaches to store hydrogen are physical storage of compressed hydrogen gas in high pressure tanks (up to 700 bar), physical storage of cryogenic hydrogen (cooled to -253°C, at pressures of 6-350 bar in insulated tanks) and the storage in the solid matrix [6][7][8][9][10]. Among these methods, the cheapest and safest storage is the adsorption of hydrogen in special solids.…”

Adsorption, reduction and storage of hydrogen within ZSM-5 zeolite exchanged with various ions: A comparative theoretical study

“…In addition, we deduced that Fe III /ZSM-5 zeolite may not be suitable for hydrogen storage because the adsorbed H 2 molecules are facile to decompose but difficult to restore [12,19]. Some other metal ions within zeolites, e.g., Mg II [9,16,25], were suggested as good candidates for hydrogen storage. Areán et al [9,10,[25][26][27][28][29] characterized the thermodynamics of H 2 adsorption in metal-exchanged zeolites and metal-organic frameworks (MOF), and observed a positive correlation between the enthalpy and entropy changes (DH 0 and DS 0 ).…”

“…Some other metal ions within zeolites, e.g., Mg II [9,16,25], were suggested as good candidates for hydrogen storage. Areán et al [9,10,[25][26][27][28][29] characterized the thermodynamics of H 2 adsorption in metal-exchanged zeolites and metal-organic frameworks (MOF), and observed a positive correlation between the enthalpy and entropy changes (DH 0 and DS 0 ). To the best of our knowledge, most of the computational works were related with the adsorption of a single H 2 molecule, and only a few with two H 2 molecules [10,22].…”