Study on nanostructured MgH2 with Fe and its oxides for hydrogen storage applications

The Catalytic Role of D-block Elements and Their Compounds for Improving Sorption Kinetics of Hydride Materials: A Review

“…They concluded that the rate-limiting step was affected during hydrogen de/absorption, due to the morphological and structural growth of the material; however, the maximum storage capacity was mostly unaffected. Recently, Gattia et al reported reduced activation energy of MgH 2 + 5 wt% Fe sample, which was found to be the main reason for the improvement of the sorption kinetics [97]. In 2020, Antiqueira et al also reported extremely fast kinetics of MgH 2 catalyzed by Fe [98].…”

The hydrogen storage properties of MgH2–Fe7S8 composites

“…The reduced apparent activation energy above demonstrated gives the indication that the dopant Fe 7 S 8 contributes to decreasing the energy barrier in the desorption process of MgH 2 , which is directly responsible for the superior improvement on the dehydrogenation properties. In recent literature 25 , activation energies for milled MgH 2 + 5 wt.% Fe, MgH 2 +5 wt.% Fe 2 O 3 and MgH 2 + 5 wt.% Fe 3 O 4 calculated by Kissinger plot were: 220.69 kJ/mol, 231.90 kJ/mol and 304.45 kJ/mol, respectively, which indicates that the addition of Fe 7 S 8 may be superior to the catalytic effect of some other additives. In addition to the hydrogen desorption behaviors, the modified impact of Fe 7 S 8 on hydrogen uptake performance on MgH 2 is also investigated by reabsorbing the dehydrogenated MgH 2 and MgH 2 -Fe 7 S 8 composites under 3 MPa of H 2 .…”

“…Chen et al 24 found that doping 5 wt.% Fe nanosheets into MgH 2 reduced the onset desorption temperature and hydrogen could be released at 182.1 o C and absorbed at 75 o C for the composite. Gattia et al 25 reported that Fe and its oxides were suitable catalyst for hydrogen storage as it largely drastically speed up reaction kinetics.…”

Enhanced Hydrogen Storage Performance of MgH2 by the Catalysis of a Novel Intersected Y2O3/NiO Hybrid

“…Common methods to improve the hydrogen storage performance of MgH 2 include alloying [9][10][11][12][13][14][15][16][17][18], nanoconfinement [19,20], nano-crystallization [21][22][23][24][25][26], and catalyst doping [27][28][29][30][31][32][33][34][35]. Alloying of Mg by combining with other metal elements, such as Al, Ni, and Ge, can produce less stable Mg-based hydrides.…”

“…One typical example is Mg 2 NiH 4 , which has a low theoretical capacity of only 3.6 wt%, though its dehydrogenation temperature is decreased to 255 • C at 1 bar equilibrium H 2 pressure [34]. Nano-crystallization is effective in modifying the thermodynamics and kinetics of MgH 2 , especially the latter [19][20][21][22][23][24][25][26]. For thermodynamic modification, theoretical calculations suggest that when the grain size of MgH 2 is reduced to 0.9 nm, the decomposition enthalpy is only 63 kJ mol −1 H 2 , corresponding to a theoretical desorption temperature of only 200 • C [36].…”