Density Functional Theory Study of Li-Functionalized Nanoporous R-Graphyne–Metal–Organic Frameworks for Reversible Hydrogen Storage
Rohit Y. Sathe, Mohd. Ussama, Hyeonhu Bae, Hoonkyung Lee, T. J. Dhilip Kumar
Abstract
Hydrogen is the most convenient recourse to shift from fossil fuels to an efficient and sustainable source of energy in automobiles. Achieving a high hydrogen weight percentage while storing hydrogen is the prime challenge in using hydrogen fuel. In the current study, a nanoporous metal–organic framework of 2.069 nm pore size having R-graphyne as a linker (GR–MOF) is reported for the first time. Employing density functional theory, the hydrogen sorption characteristics of GR–MOF functionalized with Li and its mechanism are investigated. A Kubas-like mechanism is observed in the process of hydrogen adsorption with sorption energies in the 0.25–0.27 eV range, with the highest hydrogen weight percentage of 11.95%. It is observed during the van ‘t Hoff desorption and Born–Oppenheimer molecular dynamics study that GR–MOF reversibly stores hydrogen under operable thermodynamic conditions (100–300 K, 1–3 atm). GR–MOF stands out to be a prospective material for reversible hydrogen storage under the norms set by the Department of Energy, USA.