Developing low-cost catalysts with high activity and durability is critical for on-demand H2 generation from sodium borohydride (NaBH4). Herein, amorphous NiB nanoparticles (1–10 wt% Ni) supported on calcium-deficient hydroxyapatite (HAP) were prepared by wet impregnation. Structural and surface analyses (XRD, TEM, XPS, N2 adsorption) show well-crystallized HAP, mesoporosity, and uniformly dispersed NiB nanoparticles ( \(\approx \) 30–50 nm). The 10 NiB/HAP catalyst delivers a hydrogen generation rate of 620 mL.gNi-1. min-1 at 303 K, exhibits zero-order kinetics with respect to NaBH4 with an apparent activation energy of 57.2 kJ.mol-1, and retains 58.3% of its initial activity after five consecutive cycles. XPS reveals Ni2+-dominated surfaces for the fresh catalyst and the emergence of Ni0/borate species after reaction, consistent with in-situ reduction during hydrolysis. Based on the observed surface functionalities and dispersion, we propose that BH4- activation at NiB domains is assisted by Brønsted –POH groups and Lewis-acidic Ca-vacancy sites on HAP, facilitating water activation and hydride–proton coupling. These results identify NiB/HAP as a scalable, low-cost catalyst for portable hydrogen supply.
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