Effect of MgCl2 on the Dehydrogenation Properties of NaAIH4 for Solid State Hydrogen Storage

Hydrogen is a promising energy carrier, emitting only water as a by-product. However, issues like security and storage complexity impede its widespread use. Solid-state storage, with its high volumetric capacity and safety, is ideal. Sodium aluminium hydride (NaAlH4) stands out for its high hydrogen storage capacity, low cost, and abundance. Despite these advantages, its commercialization is limited by slow sorption kinetics and high decomposition temperature. This study uses magnesium chloride (MgCl2) as a catalyst to improve NaAlH4's dehydrogenation properties. Temperature-programmed desorption showed that doping NaAlH4 with 10 wt.% MgCl2 lowers the onset hydrogen release temperature. At 300 °C, MgCl2-doped NaAlH4 desorbs about 1.6 wt.% hydrogen in 120 minutes, compared to 0.53 wt.% for undoped NaAlH4. SEM analysis revealed that MgCl2-doped NaAlH4 particles are homogeneously dispersed with less agglomeration. These factors are crucial in reducing breakdown temperature and improving kinetics. MgCl2 effectively enhances NaAlH4's hydrogen storage capacity.