In Situ Etching-Growth Synthesis of Ce-Doped NiCo-LDH/CeO ₂ Catalyst for Efficient Hydrogen Generation from Concentrated NaBH ₄ Hydrolysis

Sodium borohydride (NaBH₄) is a high-density, chemically stable hydrogen carrier for on-demand generation. In concentrated solutions, however, the rapid heat release and gas evolution often damage catalysts, creating a need for efficient and stable noble-metal-free catalysts. Herein, we report a Ce-doped NiCo-LDH/CeO₂ catalyst via an in situ etching-growth strategy. The layered double hydroxide (LDH) nanosheets are effectively anchored on the CeO₂ support, while Ce incorporation within the LDH layers creates abundant oxygen vacancies and enables reversible Ce³⁺/Ce⁴⁺ redox cycling, enhancing electron transfer and structural stability. The catalyst achieves an outstanding hydrogen generation rate of 3026.4 mL·min⁻¹·g⁻¹ and a low activation energy of 49.21 kJ·mol⁻¹ in concentrated NaBH₄ solution, comparable to that of precious metals. It retains 88% of its initial activity after five consecutive cycles. Furthermore, the scaled-up catalyst was successfully integrated into a continuous hydrogen generation system, demonstrating excellent scalability and potential for practical hydrogen supply applications.