Ultra-lightweight compositionally complex alloys with large ambient-temperature hydrogen storage capacity

• Published in: Materials today (Kidlington, England) England), 2023-07, Vol.67, p.113-126
• Main Authors: Shang, Yuanyuan, Lei, Zhifeng, Alvares, Ebert, Garroni, Sebastiano, Chen, Ting, Dore, Roberto, Rustici, Mauro, Enzo, Stefano, Schökel, Alexander, Shi, Yunzhu, Jerabek, Paul, Lu, Zhaoping, Klassen, Thomas, Pistidda, Claudio
• Format: Article
• Language: English
• Subjects: Compositionally complex alloy; Functional property; Hydrogen storage material; Metal hydride
• ISSN: 1369-7021; 1873-4103
• DOI: 10.1016/j.mattod.2023.06.012

[Display omitted] In the burgeoning field of hydrogen energy, compositionally complex alloys promise unprecedented solid-state hydrogen storage applications. However, compositionally complex alloys are facing one main challenge: reducing alloy density and increasing hydrogen storage capacity. Here, we report TiMgLi-based compositionally complex alloys with ultralow alloy density and significant room-temperature hydrogen storage capacity. The record-low alloy density (2.83 g cm−3) is made possible by multi-principal-lightweight element alloying. Introducing multiple phases instead of a single phase facilitates obtaining a large hydrogen storage capacity (2.62 wt% at 50 °C under 100 bar of H2). The kinetic modeling results indicate that three-dimensional diffusion governs the hydrogenation reaction of the current compositionally complex alloys at 50 °C. The here proposed approach broadens the horizon for designing lightweight compositionally complex alloys for hydrogen storage purposes.