The high hydrogen adsorption rate material based on graphane decorated with alkali metals

TL;DR

This study explores alkali metal-decorated graphane as a high-capacity hydrogen storage material, demonstrating it can meet and exceed DOE targets through ab initio calculations and thermodynamic analysis.

Contribution

It introduces a novel approach of chemically bonding alkali metals to graphane for enhanced hydrogen storage capacity.

Findings

Li-graphane can adsorb 3 H2 molecules per metal atom at 300 K.

Hydrogen storage capacities exceed DOE requirements.

Li-graphane shows the most promising thermodynamic stability.

Abstract

The graphane with chemically bonded alkali metals (Li, Na, K) was considered as potential material for hydrogen storage. The ab initio calculations show that such material can adsorb as many as 4 hydrogen molecules per Li, Na and K metal atoms. These values correspond to 12.20 wt%, 10.33 wt% and 8.56 wt% of hydrogen, respectively and exceed the DOE requirements. The thermodynamic analysis shows that Li-graphane complex is the most promising for hydrogen storage with ability to adsorb 3 hydrogen molecules per metal atom at 300 K and pressure in the range from 5 to 250 atm.