A review of body-centered cubic-structured alloys for hydrogen storage: composition, structure, and properties

Abstract

Hydrogen energy has gained widespread recognition for its environmentally friendly nature, high energy density and abundant resources, making it a promising energy carrier for a sustainable and clean energy society. However, safe and efficient hydrogen storage remains a significant challenge due to its inherent leakiness and flammability. To overcome these challenges, alloys featuring body-centered cubic (BCC) structures have emerged as compelling candidates for hydrogen storage, owing to their exceptional capacity to achieve high-density hydrogen storage up to 3.8 wt% at ambient temperatures. Nonetheless, their practical application faces limited dehydriding capacity, complex activation processes, high costs and poor cyclic stability. Various modification strategies have been explored to overcome these limitations, including lattice regulation, element substitution, rare earth doping and heat treatment. This progress report presents an overview of the previous advancements to enhance five crucial aspects (high-V, medium-V, low-V, V-free and high-entropy alloys) in composition design and hydrogen storage properties within BCC-structured alloys. Subsequently, an in-depth analysis is conducted to examine the relationship between crystal structures and hydrogen storage properties specific to BCC-structured alloys, covering aspects such as composition, crystal structure, hydrogen storage capacity, enthalpy and entropy. Furthermore, this review explores current challenges in this field and outlines directions for future research. These insights provide valuable guidance for the design of innovative and cost-effective hydrogen storage alloys.

Graphical abstract