الملخص الإنجليزي
A b s t r a c t:
In the present work, the bonding length, electronic structure, stability, and dehydrogenation properties of the Perovskite-type ZrNiH3 hydride, under different uniaxial/biaxial strains are investigated through ab-initio calculations based on the plane-wave pseudopotential (PW-PP) approach. The findings reveal that the uniaxial/biaxial compressive and tensile strains are responsible for the structural deformation of the ZrNiH3 crystal structure, and its lattice deformation becomes more significant with decreasing or increasing the strain magnitude. Due to the strain energy contribution, the uniaxial/biaxial strain not
only lowers the stability of ZrNiH3 but also decreases considerably the dehydrogenation enthalpy and decomposition temperature. Precisely, the formation enthalpy and decomposition temperature are reduced from 67.73 kJ/mol.H2 and 521 K for non-strained ZrNiH3 up to 33.73 kJ/mol.H2 and 259.5 K under maximal biaxial compression strain of ε ¼ 6%, and to 50.99 kJ/mol.H2 and 392.23 K for the maximal biaxial tensile strain of ε ¼ þ6%. The same phenomenon has been also observed for the uniaxial strain, where the formation enthalpy and decomposition temperature are both decreased to 39.36 kJ/mol.H2 and 302.78 K for a maximal uniaxial compressive strain of ε ¼ - 12%, and to 51.86 kJ/mol.H2 and 399 K under the maximal uniaxial tensile strain of ε¼þ12%. Moreover, the densities of states analysis suggests that the strain-induced variation in the dehydrogenation and structural properties of ZrNiH3 are strongly related to the Fermi level value of total densities of states. These ab-initio calculations demonstrate insightful novel approach into the development of Zr-based intermetallic hydrides for hydrogen storage practical applications. © 2021 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.
