The B₃N₃Li₆-nH₂ complex is investigated as a lightweight superalkali-based hydrogen storage system. DFT and ADMP simulations reveal reversible physisorption of H₂ molecules with adsorption energies in the optimal range (–0.123 to –0.100 eV), thermal stability up to 500 K, and a high storage capacity of ∼20.69 wt%.

Abstract

Efficient hydrogen storage is critical for enabling a sustainable energy future, demanding materials with exceptional capacity, reversibility, and stability under diverse conditions. Here, we investigate the hexalithioborazine (B₃N₃Li₆) as a promising hydrogen storage system, leveraging its unique structural and electronic properties using density functional theory. Systematic adsorption energy analysis reveals highly favorable adsorption energies ranging from −0.123 to −0.100 eV, ensuring reversible hydrogen uptake. Remarkably, the B₃N₃Li₆-6H₂ complex achieves a hydrogen storage capacity of 9.44 wt%, surpassing DOE benchmarks, while adsorption extends up to 15H₂ molecules, attaining an unprecedented capacity of 20.69 wt%. The stabilization arises from strong ion-induced dipole interactions between Li-atoms and H₂ molecules, facilitated by charge transfer and polarization. Thermal stability of the B₃N₃Li₆-6H₂ system is validated through atom density matrix propagation (ADMP) simulations across a broad temperature range (0–500 K), demonstrating stability even at elevated temperatures. These findings may suggest B₃N₃Li₆ as a transformative material for next-generation hydrogen storage technologies, bridging the theoretical potential and practical application gap.