Hydrogen absorption studies in ZrMnFe0.7Co0.3

The hydrogen absorption, kinetics of hydrogen absorption and thermodynamics of dissolved hydrogen in C14 Laves phase alloy ZrMnFe0.7Co0.3 are studied in the ranges 1 less than or equal to P (bar) less than or equal to 30 and 303 less than or equal to T (K) less than or equal to 473. Substituting Co at Fe site in ZrMnFe leads to the contraction of the lattice and subsequently increases the plateau pressure with a reduction in hydrogen intake capacity. The relative partial molar enthalpy and entropy of dissolved hydrogen in ZrMnFe0.7Co0.3-H are found to be in the ranges -(6-11) kJ (mol H)(-1) and -(20-42) J K-1 (mol H)(-1) respectively. The presence of alpha, (alpha + beta) and beta phases as seen in the P-C isotherms, is further confirmed by thermodynamic studies and kinetics of hydrogen absorption. (C) 2000 International Association for Hydrogen Energy. Published by Elsevier Science Ltd. All rights reserved.