Hydrogen as an energy currency: Encapsulation of inorganic Ga12N12 with alkali metals for efficient H2 adsorption as hydrogen storage materials

Abstract

Demand of efficient energy storage materials increases day by day due to high energy production rate. Hydrogen energy is considered as currency for next generation because it has numerous applications in routine life where industry has safely used hydrogen for decades in petroleum refining, glass purification, fertilizer production, pharmaceuticals, and aerospace applications. In this line, an attempt has been made to design new systems for possible hydrogen storage. Advanced quantum chemical techniques are used by employing Density Functional Theory (DFT) at B3LYP/6-31G(d,p) level. Incorporation of metals in inorganic nanoclusters always enhanced the adsorption of an analyte. In this study, the design of new gallium nitride (G12N12) nanoclusters by encapsulation with alkali metals (Li, Na and K) has been presented. Adsorption of H2 on these deigned systems is examined through various parameters like interaction energy, band gap, dipole moment, natural bonding orbitals analysis, and molecular electrostatic potential analysis. Further, global indices of reactivity are also used to unveil the natural stability and reactivity of these designed systems. Presence of different charge sites in designed systems indicated that the adsorption of hydrogen significantly enhances the charge shifting rate. Large values of natural bonding orbitals also found in support of large dipole moment values. Overall, narrow band gap with maximum charge transfer rate is found in all the designed systems, which suggested that these designed systems are efficient candidates for maximum hydrogen adsorption and storage purposes. Finally, a recommendation has been made for the experimentalists to consider these novel systems for the development of next generation hydrogen storage materials.