High capacity hydrogen storage structure based on a two-dimensional material (Ga2C6) with strong adsorption properties

Abstract

The use of solid-state devices is a promising approach to address the current technological requirements for sustainable clean energy applications. Within this context, it has become apparent that density functional theory (DFT) has emerged as a powerful tool to study intrinsic electronic characteristics and shows great potential to lead the way to novel materials exploration. Here, we have investigated H2 adsorption on Ga2C6 monolayer, a prospective model for the storage of H2 molecule because of its structural stability. The hydrogen molecules favor being adsorbed at the carbon hexagon center with a binding energy of 0.39 eV. The thermodynamic stability of the Ga2C6 monolayer upon adsorption of 22H2 molecules was evaluated at room temperature using ab-initio molecular dynamics (AIMD) simulations. It is found from the electronic structure analysis that the semiconducting Ga2C6 sheet maintain its behavior after 22H2 molecules were adsorbed. Owing to the small activation energy of about 0.0198 eV, the process of H2 molecule migration at the surface easy proceeds. This investigation demonstrates a strong (GC) gravimetric capacity around 9.65 wt%, and a desorption temperature (TD) around 213.68 K. The above findings imply that the Ga2C6 monolayer may serve as a suitable medium for hydrogen adsorption.