A study of the effect of the addition of nanostructured carbonaceous catalysts in the dehydrogenation mechanism of magnesium borohydride

作者：Paduani C^*

来源：Journal of Materials Chemistry A, 2015, 3(2): 819-824.

DOI：10.1039/c4ta05825a

In this work first principles calculations based on density functional theory are performed to study the effect of using carbon fullerenes C-60 (buckyballs) or C-67 (nanohorns) as catalyzing agents in the dehydrogenation of magnesium borohydride. This study focuses on thermodynamic quantities, i. e., the energy changes following H-removal with and without the catalysts. The calculated energy cost for H-removal from Mg(BH4)(2) is 4.18 eV, which decreases to 4.08 eV when adding C-60 and to 3.32 eV in the presence of C-67. With a combined addition of titanium besides the carbonaceous catalysts the H-removal energy cost decreases to 4.04 eV and 2.78 eV, in the presence of C-60 and C-67, respectively. This arises from the weakening of the B-H bonds which takes place through an interplay mechanism of charge transfer between the Mg(BH4)(2) cluster and the catalysts.

• 出版日期2015