In Situ Hydrothermal Assembly of MoS ₂ /h-BN Nanoscale Heterostructures on Nickel Foam: Structure–Mechanism Insights & Electrochemical Hydrogen Storage

Solid-state hydrogen storage requires nanomaterials with high surface accessibility, fast and reversible adsorption kinetics, and structurally coherent interfaces. In this study, MoS2/h-BN van der Waals heterostructures were synthesized via an in situ hydrothermal route, yielding hierarchical nanoscale flower-like MoS2 assemblies anchored onto disc-like h-BN. Structural analysis revealed a MoS2/MoO3 core–shell configuration during early nucleation and a vdW-dominated misaligned interface between MoS2 (0.65 nm) and h-BN (0.33 nm), as confirmed by high-resolution transmission electron microscopy (HR-TEM). Electrochemical evaluation showed that the heterostructures deliver a hydrogen-storage capacity of 539.1 mAh g–1, representing a 120% increase over that of pristine h-BN (244.8 mAh g–1). The electrochemical impedance spectroscopy (EIS) analysis demonstrated a 20% reduction in charge-transfer resistance (∼15 Ω vs ∼12 Ω), along with a significantly enhanced capacitive contribution, indicating a transition from diffusion-limited chemisorption in h-BN to faster, physisorption-assisted storage in the MoS2/h-BN heterostructure. These quantitative insights confirm that rational interface engineering in 2D/2D heterostructures can modulate adsorption mechanisms, accelerate hydrogen-storage kinetics, and enable the development of high-performance solid-state hydrogen-storage nanomaterials.