Magnesium is one of the main candidates for hydrogen storage, mainly because of its low price, availability and high gravimetric capacity of above 6 wt.%.
Used without a catalyst, however, magnesium exhibits the disadvantages of high operating temperature and slow kinetics. Thus the developpment of an applicable catalyst is very significant
Without catalysis, magnesium hydride forms does not form easily and, even at 350 and 400oC, the reaction is slow and difficult to complete.
In our experiments, magnesium powder was intermixed by a brief ball milling with one of our catalytic compounds and the catalyzed sample was exposed to hydrogen at room temperature under hydrogen pressure of 10 bars, without any preheating or activation. The immediate hydrogen uptake of the magnesium sample occurred, ultimately reaching over 6.5 wt.% capacity. After hydrogenation, the material exhibited an x-ray diffraction pattern characteristic for MgH2.
Catalyzed Magnesium Preparation
starting material: commercial Mg shavings
before and after ball milling
ball milled Mg catalyst particle on Mg powder
Hydrogen Absorption by the Catalyzed Magnesium
Absorption in excess of 6 wt.% at room temperature
Complete hydrogenation at room temperature:
formation of magnesium hydride MgH2
x-ray diffraction confirmation of the reaction completion
Reversible cyling of the Catalyzed Magnesium Hydride
Reversible Hydrogen Storage Material
- Hydrogen capacity : > 6 wt.%
- Re-hydrogenation can be done at any temperature between RT and above
- Very low cost and abundant availability of the material
- High stability of the hydride = indefinite storage without losses or boil off
Magnesium - based hydrogen storage systems
Mg -Ni, Mg-Al etc.
lower temperature of operation at the cost of reduced capacity as compared to pure MgH2
Other examples of Mg - based systems
Mg - Na system
MgH2 + NaH ⇒ NaMgH3 (6 wt.%)
Mg - Ti system
Mg – Ti system - immiscible, - no equilibrium phases
Formed a metastable fcc phase within a certain range of compositions
Absorption at room temperature of a catalyzed Mg-Ti sample
Fcc phase – absorbed hydrogen without crystallographic transformation
Please contact us with inquires related to purchase of our hydrogen generators, catalysts or catalyzed materials at email@example.com