Hydrogen Storage On Lithium Chloride / Lithium Bromide Surface At Cryogenic Temperature.pdf

# Hydrogen Storage on Lithium Chloride/Lithium Bromide Surface at Cryogenic Temperatures

This research article explores the potential of Lithium chloride (LiCl) and Lithium bromide (LiBr) as templates for low-temperature hydrogen storage. Using density functional theory (DFT), the authors study the structure and chemical reactivity of these materials, focusing on quasisorption—a process where molecular hydrogen interacts with building blocks through electrovalent interaction.

## Key Findings:

- High Gravimetric Weight Percentage: Both LiCl and LiBr demonstrate promising results, absorbing up to 10 H2 molecules per molecule with gravimetric weight percentages of 32.00% for LiCl and 18.71% for LiBr.
- Spontaneous Hydrogen Adsorption: The Gibbs free energy changes indicate a spontaneous hydrogen adsorption process at cryogenic temperatures, suggesting these materials are suitable for low-temperature storage.
- Comparative Analysis: The study compares LiF, LiCl, and LiBr, highlighting their reactivity parameters, including hardness, electronegativity, electrophilicity, and NBO charge transfer interactions.

## Methodology:

The researchers utilized Gaussian 16w software for optimizing ground state geometries using various functionals and basis sets (CAM-B3LYP, ωB97X-D, LanL2DZ, and 6-311+G(d,p)). Frequency calculations were performed to ensure the stability of the optimized structures.

## Significance:

The article contributes to the ongoing search for efficient hydrogen storage methods, particularly at cryogenic temperatures. LiCl and LiBr emerge as potential candidates due to their high storage capacities and reversible adsorption-desorption mechanisms, aligning with the US Department of Energy's 2015 targets for green fuel development.