Improving the hydrogen storage and ammonia detection and capture in BeN3 monolayer via lithium decoration and strain engineering

Abstract

Hydrogen and ammonia are promising candidates for future energy applications due to their potential for clean and efficient power generation. However, their storage remains a critical challenge, necessitating the search for advanced materials with high capacity and reversibility. This study explores the potential of the new BeN 3 monolayer for hydrogen storage, ammonia detection, and capture using density functional theory. Due to weak adsorption of hydrogen molecules, a one-sided lithium decoration was introduced to enhance storage capacity. Lithium atoms preferentially bind to nitrogen sites with an energy of −1.37 eV and diffusion barriers of 1.00 eV and 0.62 eV along two stable positions, indicating stability without aggregation. The decorated monolayer can adsorb 16H 2 molecules, achieving a gravimetric storage capacity of 6.83 wt%, surpassing the DOE's 2025 target of 6.5 wt%. This modification increases the adsorption energy of hydrogen molecules from −0.06 eV to −0.18 eV in a fully occupied monolayer, demonstrating a promising strategy for improving storage. Additionally, band gap variation after NH 3 adsorption on intrinsic BeN 3 indicates potential for ammonia detection. Biaxial strain engineering was applied for capture tailoring, with an 8 % strained monolayer showing phonon stability and adsorption energy of −0.58 eV, enabling effective capture and release control.

Topics & Concepts