Experimental and Theoretical Investigations on the Influence of A on the Hydrogen Sorption Properties of ANiy Compounds, A = {Y, Sm, Gd}

The phase stability, electronic structure, magnetic and mechanical properties of ANiy compounds, A = {Y, Sm, Gd}, y = {2, 3, 72, 195, 4, 5}, and A2Ni7H8 hydrides have been investigated by systematic first-principles calculations. Supported by a discussion to understand the role of A and y parameters, the results are compared with published and new experimental data regarding the heat of formation of some compounds and their hydrides. The main results can be summarized as follows: (i) ANi3 and A2Ni7 are clearly stable by the density functional theory calculation, whereas the stability of ANiy for y>72 is not highlighted distinctively, in agreement with the difficulty to identify a single phase by experimental synthesis for some compounds such as Y5Ni19; (ii) ANiy compounds are found more rigid for A = Y and may explained the difficulty to observe Y5Ni19 in comparison with Sm5Ni19 and Gd5Ni19; and (iii) the calculated and measured heats of formation of A2Ni7H8 hydrides are found in good agreement, around −2...

[1]  Junxian Zhang,et al.  Relationship between H2 sorption, electrochemical cycling and aqueous corrosion properties in A5Ni19 hydride-forming alloys (A = Gd, Sm) , 2018, Journal of Power Sources.

[2]  Junxian Zhang,et al.  Relationship between H 2 sorption properties and aqueous corrosion mechanisms in A 2 Ni 7 hydride forming alloys (A = Y, Gd or Sm) , 2016 .

[3]  Junxian Zhang,et al.  Structural and Hydrogen Storage Properties of Y2Ni7 Deuterides Studied by Neutron Powder Diffraction , 2015 .

[4]  A. Hoshikawa,et al.  Hydrogenation and structural properties of Gd2Ni7 with superlattice structure , 2012 .

[5]  Junxian Zhang,et al.  Structural Stability of ABy Phases in the (La,Mg)–Ni System Obtained by Density Functional Theory Calculations , 2011 .

[6]  A. Hoshikawa,et al.  Synthesis of new compound Gd5Ni19 with a superlattice structure and hydrogen absorption properties. , 2011, Inorganic chemistry.

[7]  B. Knosp,et al.  Elaboration and characterization of unreported (Pr,Nd)5Ni19 hydrides , 2011 .

[8]  Yumiko Nakamura,et al.  Synthesis and crystal structure of a Pr5Ni19 superlattice alloy and its hydrogen absorption-desorption property. , 2011, Inorganic chemistry.

[9]  B. Knosp,et al.  Elaboration and characterization of magnesium-substituted La5Ni19 hydride forming alloys as active materials for negative electrode in Ni-MH battery , 2009 .

[10]  M. Sato,et al.  Mg substitution effect on the hydrogenation behaviour, thermodynamic and structural properties of the La2Ni7-H(D)2 system , 2008 .

[11]  H. Fjellvåg,et al.  Crystal chemistry and metal-hydrogen bonding in anisotropic and interstitial hydrides of intermetallics of rare earth (R) and transition metals (T), RT3 and R2T7 , 2008 .

[12]  T. Sakai,et al.  Stacking structures and electrode performances of rare earth-Mg-Ni-based alloys for advanced nickel-metal hydride battery , 2007 .

[13]  M. Latroche,et al.  Homogeneity range and order–disorder transitions in R1−xNi2 Laves phase compounds , 2006 .

[14]  M. Sato,et al.  Novel intermetallic hydrides , 2006 .

[15]  M. Gupta,et al.  Relationship between compressibility and hydrogen absorption in some Haucke compounds , 2005 .

[16]  M. Latroche.  Structural and thermodynamic properties of metallic hydrides used for energy storage , 2004 .

[17]  J. Joubert,et al.  Intermetallic compounds as negative electrodes of Ni/MH batteries , 2001 .

[18]  A. Savin,et al.  Classification of chemical bonds based on topological analysis of electron localization functions , 1994, Nature.

[19]  Axel D. Becke,et al.  A Simple Measure of Electron Localization in Atomic and Molecular-Systems , 1990 .

[20]  M. Gupta.  Electronic properties of LaNi5 and LaNi5H7 , 1987 .

[21]  T. Masumoto,et al.  Hydrogen induced amorphization in RNi2 laves phases , 1987 .

[22]  Y. Kitano,et al.  Polytypes of the intermetallic compound Sm5Ni19 , 1982 .

[23]  A. Switendick.  Band Structure Calculations for Metal Hydrogen Systems* , 1979 .

[24]  Y. Khan.  Variation of period with valence electron concentration in RTy one‐dimensional long‐period superstructures , 1974 .

[25]  K. Buschow,et al.  The crystal structure of rare-earth nickel compounds of the type R2Ni7 , 1970 .