Hydrogen storage performance of 2LiH + MgB2 doped with hydrothermal-synthesized ZrO2 nanorods

In this study, we synthesized ZrO 2 nanorods through a hydrothermal process as a catalyst precursor for the reversible hydrogen storage reaction between 2LiH + MgB 2 and 2LiBH 4  + MgH 2. The 2LiH + MgB 2 composites doped with the ZrO 2 nanorods demonstrated superior and stable hydriding/dehydriding kinetics upon cycling. The XRD , SEM and HRTEM results revealed that the doped ZrO 2 nanorods were transformed into ZrB 2 nanoparticles with a size of a few nanometers during the first hydrogenation. The initial nanosize of the ZrO 2 catalyst precursor accounted for the formation of extremely fine ZrB 2 nanoparticles , which acted as heterogeneous nuclei of MgB 2 . The present study provides a new route for performance enhancement of complex hydride composites through manipulating the nanostructure of catalysts.