Exploration of adsorption behavior, electronic nature and NLO response of hydrogen adsorbed Alkali metals (Li, Na and K) encapsulated Al12N12 nanocages

Abstract

Due to the increasing demand of Al[Formula: see text]N[Formula: see text] in optoelectronics and sensing materials, we intended to investigate the adsorption behavior, electronic nature and NLO response of hydrogen and different metals decorated Al[Formula: see text]N[Formula: see text] nanocages. Different systems are designed by hydrogen adsorption and encapsulation of metals (Li, Na and K) in Al[Formula: see text]N[Formula: see text]. Density functional theory at B3LYP functional with conjunction of 6-31G([Formula: see text], [Formula: see text] basis set is utilized in order to gain optimized geometries. Different calculations including linear and first-order hyperpolarizability are conducted at same level of theory. Instead of chemiosorption, a phyisosorption phenomenon is seen in all hydrogen adsorbed metal encapsulated Al[Formula: see text]N[Formula: see text] nanoclusters. The [Formula: see text] analysis confirmed the charge separation in hydrogen adsorbed metal encapsulated nanocages. Molecular electrostatic potential (MEP) analysis cleared the different charge sites in all the systems. Similarly, frontier molecular orbitals analysis corroborated the charge densities shifting upon hydrogen adsorption on metal encapsulated AlN nanocages. HOMO–LUMO band gaps suggest effective use of H2-M-AlN in sensing materials. Global indices of reactivity also endorsed that all hydrogen adsorbed metal encapsulated systems are better materials than pure Al[Formula: see text]N[Formula: see text] nanocage for sensing applications. Lastly, linear and first hyperpolarizability of H2-M-AlN nanocages are found to be greater than M-AlN and pure AlN nanocages. Results of these parameters recommend metal encapsulated nanocages as efficient contributors for the applications in hydrogen sensing and optoelectronic devices.