First-principles insights of na-decorated B7N5 monolayer for advanced hydrogen storage

Abstract

Hydrogen is a versatile energy source, emerging as a promising alternative to traditional fossil fuels. Recently, two-dimensional (2D) materials have gained significant attention. Among these, new stable B₇N₅ monolayer have been discovered, demonstrating promising optical properties and enhanced absorption. In this context, our study explores the potential of Na decoration on B₇N₅ for hydrogen storage using density functional theory (DFT) simulations. The Na@B₇N₅ system can be saturated with up to 32 H₂ molecules, showcasing an impressive gravimetric capacity of 7.70 wt%. Ab initio molecular dynamics (AIMD) simulations at 200 K and 300 K indicate fast desorption dynamics and reversible hydrogen storage. At the same time, the system retains its structural integrity at 290 K and pressures above 10 bar, making it an ideal substrate for H₂ storage.