DOI: https://doi.org/10.55373/mjchem.v28i4.64

Keywords: Hydrogen storage, hydrolysis, borohydrides, catalysis, boron nitride

Abstract

Sodium borohydride (NaBH₄) is emerging as a highly promising hydrogen storage material due to its exceptional gravimetric hydrogen storage capacity (10.7 wt%). Its ability to rapidly release hydrogen through hydrolysis under ambient conditions makes it an ideal candidate for on-demand power generation in fuel cells. However, without a catalyst, the hydrolysis kinetics of NaBH₄ remain slow. Traditionally, Co-B alloy has been used as an effective catalyst, though it tends to agglomerate, reducing both activity and durability. In this study, amorphous hexagonal boron nitride (h-BN) was successfully synthesized and employed as a support material to improve the stability of Co particles, forming the Co/BN catalyst. A systematic investigation of transition metal-based catalysts (Co/BN, Ni/BN, Cu/BN, and Sn/BN) for NaBH₄ hydrolysis revealed 10 wt% Co/BN as the most active catalyst, achieving a hydrogen yield of 3.6 mol H₂/mol NaBH₄ at 30 °C with an activation energy of 29.23 kJ mol⁻¹. These findings provide valuable insights into catalytic mechanisms and contribute to the development of an efficient, cost-effective hydrogen production method using Co-based catalysts in heterogeneous reactions.