Hydrogen storage properties of Mg[BH₄]₂
- Matsunaga, Tomoya EMPA, Department Environment, Energy and Mobility, Abt. 138 “Hydrogen & Energy”, Dübendorf, Switzerland - University of Fribourg, Physics Department, Switzerland
- Buchter, Florian EMPA, Department Environment, Energy and Mobility, Abt. 138 “Hydrogen & Energy”, Dübendorf, Switzerland - University of Fribourg, Physics Department, Switzerland
- Mauron, Phillipe EMPA, Department Environment, Energy and Mobility, Abt. 138 “Hydrogen & Energy”, Dübendorf, Switzerland - University of Fribourg, Physics Department, Switzerland
- Bielmann, Michael EMPA, Department Environment, Energy and Mobility, Abt. 138 “Hydrogen & Energy”, Dübendorf, Switzerland - University of Fribourg, Physics Department, Switzerland
- Nakamori, Y. Institute for Materials Research, Tohoku University, Sendai Japan
- Orimo, S. Institute for Materials Research, Tohoku University, Sendai Japan
- Ohba, N. Toyota Central Research and Development Laboratories, Inc., Nagakute, Aichi, Japan
- Miwa, K. Toyota Central Research and Development Laboratories, Inc., Nagakute, Aichi, Japan
- Towata, S. Toyota Central Research and Development Laboratories, Inc., Nagakute, Aichi, Japan
- Züttel, Andreas EMPA, Department Environment, Energy and Mobility, Abt. 138 “Hydrogen & Energy”, Dübendorf, Switzerland - University of Fribourg, Physics Department, Switzerland
-
18.05.2007
Published in:
- Journal of Alloys and Compounds. - 2008, vol. 259, no. 1-2, p. 583-588
English
Among the large variety of possible complex hydrides only few exhibit a large gravimetric hydrogen density and stability around 40 kJ mol⁻¹H₂. Mg[BH₄]₂ is based on theoretical approaches a complex hydride with an equilibrium hydrogen pressure of approximately 1 bar at room temperature and a hydrogen content of 14.9 mass%. The reaction of Li[BH₄] with MgCl₂ at elevated temperatures was investigated as a possible route to synthesize Mg[BH₄]₂. Li[BH₄] reacts with MgCl₂ at a temperature >523 K at a pressure of 10 MPa of hydrogen, where the product contains LiCl and Mg[BH₄]₂. The desorption pc-isotherm of the product obtained at 623 K shows two flat plateaus, which indicates that the decomposition of the product consists of a two-step reaction. The products of the first and the second decomposition reaction were analyzed by means of X-ray diffraction and found to be MgH₂ and Mg, respectively. The enthalpy for the first decomposition reaction was determined to be ΔH = −39.3 kJ mol⁻¹H₂ by the Van’t Hoff plot of the equilibrium measurements between 563 K and 623 K, which is significantly lower than that for pure Li[BH₄] (ΔH = −74.9 kJ mol⁻¹H₂). However, only the second reaction step (MgH₂ → Mg) is reversible at the condition up to 623 K at 10 MPa of hydrogen.
- Faculty
- Faculté des sciences et de médecine
- Department
- Département de Physique
- Language
-
- English
- Classification
- Physics
- License
- License undefined
- Identifiers
-
- RERO DOC 9696
- DOI 10.1016/j.jallcom.2007.05.054
- Persistent URL
- https://folia.unifr.ch/unifr/documents/300800
Statistics
Document views: 28
File downloads:
- zuettel_hsp.pdf: 44