TY - JOUR
T1 - Thermodynamical stability and electronic structure of a perovskite-type hydride, NaMgH3
AU - Ikeda, K.
AU - Kato, S.
AU - Shinzato, Y.
AU - Okuda, N.
AU - Nakamori, Y.
AU - Kitano, A.
AU - Yukawa, H.
AU - Morinaga, M.
AU - Orimo, S.
N1 - Funding Information:
The authors would like to thank Dr. H. Yamada and Ms. M. Iwabuchi for technical support. The synchrotron radiation experiments were performed at the BL19B2 in the SPring-8 with the approval of the Japan Synchrotron Radiation Research Institute (JASRI) (Proposal No. 2005B0899), collaborated with Honda R&D Co., Ltd. This work was partially supported by the ‘Grant-in-Aid for Exploratory Research #15656003’ of the Ministry of Education, Culture, Sports, Science and Technology, and by the ‘Nano-Material Developing Project’ of Institute for Materials Research, Tohoku University. One of the authors (K.I.) is grateful for the Research Fellowships of the Japan Society for the Promotion of Science for Young Scientists.
PY - 2007/10/31
Y1 - 2007/10/31
N2 - Thermodynamical stability and electronic structure of a perovskite-type hydride, NaMgH3, exhibiting reversible decomposition and recombination reactions, were studied experimentally. NaMgH3 decomposes in two steps accompanying hydrogen desorption reactions, and the enthalpy change (ΔH) and the entropy change (ΔS) are calculated to be ΔH(1) = -93.9(6) kJ/mol H2 and ΔS(1) = -116.2(9) J/K mol H2 for the first step, and ΔH(2) = -102.2(4) kJ/mol H2 and ΔS(2) = -125.9(6) J/K mol H2 for the second step, respectively. Maximum entropy method (MEM)/Rietveld analysis of synchrotron X-ray diffraction profiles indicated that NaMgH3 contains two hydrogen anions at the different occupation sites.
AB - Thermodynamical stability and electronic structure of a perovskite-type hydride, NaMgH3, exhibiting reversible decomposition and recombination reactions, were studied experimentally. NaMgH3 decomposes in two steps accompanying hydrogen desorption reactions, and the enthalpy change (ΔH) and the entropy change (ΔS) are calculated to be ΔH(1) = -93.9(6) kJ/mol H2 and ΔS(1) = -116.2(9) J/K mol H2 for the first step, and ΔH(2) = -102.2(4) kJ/mol H2 and ΔS(2) = -125.9(6) J/K mol H2 for the second step, respectively. Maximum entropy method (MEM)/Rietveld analysis of synchrotron X-ray diffraction profiles indicated that NaMgH3 contains two hydrogen anions at the different occupation sites.
KW - Crystal structure and symmetry
KW - Hydrogen storage materials
KW - Mechanical alloying
KW - Synchrotron radiation
KW - X-ray diffraction
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U2 - 10.1016/j.jallcom.2007.03.093
DO - 10.1016/j.jallcom.2007.03.093
M3 - Article
AN - SCOPUS:35148845267
SN - 0925-8388
VL - 446-447
SP - 162
EP - 165
JO - Journal of Alloys and Compounds
JF - Journal of Alloys and Compounds
ER -