MoSe2 hollow nanospheres decorated with FeNi3 nanoparticles for enhancing the hydrogen storage properties of MgH2

The FeNi 3 , MoSe 2 and MoSe 2 @FeNi 3 hollow nano-spheres synthesized by wet chemical method are used for the first time to improve the hydrogen storage properties of the MgH 2 . The results show that they all possess excellent catalytic activity in the hydrogen desorption/sorption reactions of MgH 2 . Because of the synergistic catalytic effect of MoSe 2 and FeNi 3 , the MoSe 2 @FeNi 3 has the most outstanding catalytic effect. In detail, the onset dehydrogenation temperature of MgH 2 is reduced from 310 °C to 194 °C, and its maximum dehydrogenation rate is increased by 19.8 times by the introduction of 10 wt% MoSe 2 @FeNi 3 . Furthermore, the 10 wt% MoSe 2 @FeNi 3 -doped MgH 2 sample, 5.8 wt% H 2 can be absorbed in 0.5 min at 150 °C. However, the un-doped MgH 2 sample hardly absorbs hydrogen under the same conditions. The onset hydrogen absorption temperature of the composite is only 73 °C. More importantly, it has an excellent cycling stability. These improvements are because the in situ formed MgSe, Mo, Mg 2 Ni and Fe can serve as active species, and they as well as their homogeneous distribution on MgH 2 matrix can remain stable during dehydrogenation/hydrogenation. In addition, the presence of Mg 2 Ni can convert MgH 2 to an easier pathway of hydrogen absorption/desorption. These help to facilitate the hydrogen storage performance of MgH 2 .