Enhanced hydrogen storage via NaH and GO composites: Structural, morphological and spectroscopic insights

In this work, a novel composite material composed of NaH and GO was prepared and investigated for hydrogen storage. The composite was prepared using ball milling techniques and was also characterized by Raman spectroscopy, XRD, BET measurements, and SEM. Raman spectroscopy established hydrogenation induced the formation of large defects in the GO matrix and shifts in phonon modes of NaH vibrational modes, establishing structural changes through hydrogen interaction. XRD findings indicated lattice contraction and decrease in crystallite size upon hydrogen absorption, and secondary phases such as NaOH and NaO₂H₃ were also present due to the sensitivity of NaH to environmental oxygen and humidity. BET analysis revealed a surface area of 9.42 m²/g with an average pore diameter of ≤68.79 nm, and SEM images confirmed a well-dispersed, fractured morphology for hydrogen uptake. Hydrogen storage capacities at 5, 10, and 15 bar showed pressure-dependent behavior, and the composite was observed to achieve a maximum capacity of 1.9 wt% at 15 bar. The interaction between GO and NaH enhances structural stability, surface accessibility, and defect density, making the NaH+GO composite a promising candidate for high-efficiency solid-state hydrogen storage applications.