Author/Authors :
Li, H-W Tohoku University - Institute for Materials Research, Japan , Miwa, K Toyota Central R D Labs Incorporated, Japan , Ohba, N Toyota Central R D Labs Incorporated, Japan , Fujita, T Tohoku University - WPI Advanced Institute for Materials Research, Japan , Sato, T. Tohoku University - Institute for Materials Research, Japan , Yan, Y Tohoku University - Institute for Materials Research, Japan , Towata, S Toyota Central R D Labs Incorporated, Japan , Chen, M W Tohoku University - WPI Advanced Institute for Materials Research, Japan , Orimo, S Tohoku University - Institute for Materials Research, Japan
Abstract :
Experimental and theoretical studies on Mg(BH4)2 were carried out from the viewpoint of the formation of the intermediate compound MgB12H12 with B12H12 cluster. The full dehydriding and partial rehydriding reactions of Mg(BH4)2 occurred according to the following multistep reaction: mathrm {Mg(BH4)2 rightarrow 1/6 MgB12H12 + 5/6 MgH2 +13/6 H2 leftrightarrow MgH2+2B+3H2 leftrightarrow Mg+2B +4H2. The dehydriding reaction of Mg(BH4)2 starts at approximately 520 K, and 14.4 mass% of hydrogen is released upon heating to 800 K. Furthermore, 6.1 mass% of hydrogen can be rehydrided through the formation of MgB12H12. The mechanism for the formation of MgB12H12 under the present rehydriding condition is also discussed
