Density Functional Theory study of the hydrogen storage in a vacancy zone of an iron-nickel cell

G. CANTO; I. SALAZAR-EHUAN; J. GONZÁLEZ-SÁNCHEZ; A. TAPIA; R. QUIJANO; S. SIMONETTI

INTERNATIONAL JOURNAL OF HYDROGEN ENERGY

PERGAMON-ELSEVIER SCIENCE LTD

Lugar: Amsterdam; Año: 2014 vol. 39 p. 8744 - 8748

0360-3199

Calculations using the SIESTA code have been performed to study the location of one and two hydrogens in a vacancy zone of a Fe50Ni50 cell. H debilitates the original metalemetal bonds by forming strong interactions with the metallic matrix. The FeeH interaction is stronger than the NieH interaction. The Hemetal exchange contributes to this process. After first H atom adsorption, the strength of the nearest FeeFe, FeeNi and NieNi bonds decreases to about 89%, 15% and 1%, respectively. Then, the FeeFe bond is the most affected. The adsorption of an additional H atom modified the metalemetal strength in a lesser percent. Then, no additional decohesion is observed in the metallic bonds when two H atoms are present but in this case more metallic bonds are affected. The HeH interaction is small; an H2 molecule is not formed in the vacancy zone of the Fe50Ni50 cell.