Improving solid-state hydriding and dehydriding properties of the LiBH4 plus MgH2 system with the addition of Mn and V dopants

The hydriding process of the 2LiH + MgB2 mixture is controlled by outward diffusion of Mg and inward diffusion of Li and H within MgB2 crystals to form LiBH4. This study explores the feasibility of using transition metal dopants, such as Mn and V, to enhance the diffusion rate and thus the hydriding kinetics. It is found that Mn can indeed enhance the hydriding kinetics of the 2LiH + MgB2 mixture, while V does not. The major factor in enhancing the diffusion rate and thus the hydriding kinetics is related to the dopant's ability to induce the lattice distortion of MgB2 crystals. This study demonstrates that the kinetics of the diffusion controlled solid-state hydriding process can be improved by doping if the dopant is properly selected.