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

The FeNi3, MoSe2 and MoSe2@FeNi3 hollow nano-spheres synthesized by wet chemical method are used for the first time to improve the hydrogen storage properties of the MgH2. The results show that they all possess excellent catalytic activity in the hydrogen desorption/sorption reactions of MgH2. Because of the synergistic catalytic effect of MoSe2 and FeNi3, the MoSe2@FeNi3 has the most outstanding catalytic effect. In detail, the onset dehydrogenation temperature of MgH2 is reduced from 310 degrees C to 194 degrees C, and its maximum dehydrogenation rate is increased by 19.8 times by the introduction of 10 wt% MoSe2@FeNi3. Furthermore, the 10 wt% MoSe2@FeNi3-doped MgH2 sample, 5.8 wt% H-2 can be absorbed in 0.5 min at 150 degrees C. However, the un-doped MgH2 sample hardly absorbs hydrogen under the same conditions. The onset hydrogen absorption temperature of the composite is only 73 degrees C. More importantly, it has an excellent cycling stability. These improvements are because the in situ formed MgSe, Mo, Mg2Ni and Fe can serve as active species, and they as well as their homogeneous distribution on MgH2 matrix can remain stable during dehydrogenation/hydrogenation. In addition, the presence of Mg2Ni can convert MgH2 to an easier pathway of hydrogen absorption/desorption. These help to facilitate the hydrogen storage performance of MgH2. (c) 2020 Elsevier B.V. All rights reserved.