Magnetized/charged MgH2-based hydrogen storage materials

Abstract

We propose two methods to facilitate the Mg–H bond cleavage of magnesium hydride MgH2. We found via density functional calculations that Mn (or Fe), when inserted between two MgH2, exhibits a much higher catalytic activity than the other 3d transition metal elements because of the induced spin polarization of the MgH2. We also found that an ionized MgH2 (MgH2+) has considerably softer Mg–H bonds. We can thus significantly reduce the H2 desorption temperatures from MgH2 to practical levels, ∼400K, by forming an alloy hydride with Mn (or Fe), and/or ionizing the MgH2.