While borohydrides, such as NaBH₄, were often used as supplements to improve hydrogen storage properties of Mg/MgH₂ systems, they have long suffered from high decomposition temperature and irreversible dehydrogenation process. Here, we report that NaBH₄ can reversibly serve as a hydrogen storage host and reactant for Mg/MgH₂ systems under mild reaction conditions with the help of Al/AlH₃. 90 wt%MgH₂–5 wt.%AlH₃–5 wt.%NaBH₄ (M-5AB) has been successfully synthesized using the conventional mechanical alloying technique. The dehydrogenation activation energy and enthalpy are 20% and 9% reduced than those of pure Mg/MgH₂. After 10 hydrogen absorption and desorption cycles, the hydrogen storage capacity of M-5AB can reach 6.35 wt%. The X-ray diffraction (XRD) and the transmission electron microscope (TEM) measurements revealed that the interface of additives and Mg/MgH₂ decompose to Mg₁₇Al₁₂, MgAlB₄ and NaH phases. The Mg₁₇Al₁₂ and MgAlB₄ phases reduces the barrier of free energies of hydrogenated and dehydrogenated states, helping NaBH₄ to recover after rehydrogenation. These discoveries indicate that Al species can boost the decomposition and reformation of NaBH₄, providing a wider degree of freedom for the material design of Mg-based hydrogen storage materials.

虽然硼氢化物如NaBH _{4经常被用作改善Mg/MgH 2}体系储氢性能的补充剂，但它们长期以来一直受到高分解温度和不可逆脱氢过程的困扰。在这里，我们报道了在 Al/AlH _{3的帮助下，NaBH 4}可以在温和的反应条件下可逆地作为 Mg/MgH ₂体系的储氢主体和反应物。90 wt% MgH ₂ –5 wt.%AlH ₃ –5 wt.%NaBH ₄ (M-5AB) 已使用传统的机械合金化技术成功合成。脱氢活化能和焓比纯Mg/MgH _{2降低20%和9%}. 经过10次吸放氢循环后，M-5AB的储氢能力可达6.35 wt%。X射线衍射(XRD)和透射电子显微镜(TEM)测量表明，添加剂和Mg/MgH ₂的界面分解为Mg ₁₇ Al ₁₂、MgAlB ₄和NaH相。Mg ₁₇ Al ₁₂和MgAlB ₄相降低了氢化和脱氢态的自由能势垒，有助于NaBH ₄在再氢化后恢复。这些发现表明Al可以促进NaBH _{4的分解和重整}，为镁基储氢材料的材料设计提供了更大的自由度。