LiBH (LB in short) with a hydrogen capacity as high as 18.5 wt% and a low molecular weight (21.78 g mol) is among the most promising candidates for the hydrogen-based economy. However, current major technologies in (re)generation of LB rely heavily on energy-intensive processes, which greatly prohibits practical scaling-up of applications. Here we report a sustainable and effective approach to (re)generate LB via converting renewable H in crystalline water into H, achieving a desirable yield of ∼50%. This one-step synthesis method relies on the reaction between spent fuels, specifically LiBO·HO, and Mg-based alloys to form LB under ambient atmosphere. Notably, our approach surpasses the efficiency of other conventional method, such as LiH-B-H and MgH-LiBO systems, which not only bypasses the energy-intensive dehydration procedure of LiBO·HO (∼470 ℃) but also eliminates the use of costly hydrides or high-pressure H. Our findings indicate that Mg participated in the regeneration process prior to Al in Mg-Al alloys and [BH] is gradually evolved from other intermediate species [BH(OH)] ( = 0, 1, 2, 3). By combining hydrogen release and efficient storage of hydrogen-rich substrate in a closed materials cycle, this study may shed light on a promising step toward application of renewable hydrogen in a fuel cell-based hydrogen economy.

中文翻译：

---

利用乏燃料中的自维持氢实现 LiBH4 的一步再生——储存可再生氢的一种途径

LiBH（简称LB）具有高达18.5 wt%的氢容量和低分子量（21.78 g mol），是氢基经济最有前途的候选材料之一。然而，当前LB（再）生成的主要技术严重依赖于能源密集型工艺，这极大地阻碍了应用的实际规模化。在此，我们报告了一种可持续且有效的方法，通过将结晶水中的可再生 H 转化为 H 来（重新）生成 LB，实现了约 50% 的理想产率。这种一步合成方法依赖于乏燃料（特别是LiBO·H2O）与镁基合金在环境大气下反应形成LB。值得注意的是，我们的方法超越了其他传统方法的效率，例如LiH-BH和MgH-LiBO系统，它不仅绕过了LiBO·H2O（〜470℃）的能源密集型脱水程序，而且消除了昂贵的氢化物的使用我们的研究结果表明，Mg 在 Mg-Al 合金中先于 Al 参与再生过程，并且 [BH] 是从其他中间物质 [BH(OH)] ( = 0, 1, 2, 3 ）。通过在封闭材料循环中结合氢释放和富氢基质的有效存储，这项研究可能为可再生氢在基于燃料电池的氢经济中的应用迈出了有希望的一步。