Solid-state hydrogen storage: Theoretical study of ScPd3H4 hydride

Abstract

In the present study, we present a comprehensive theoretical study of the structural, mechanical, optical, and thermodynamic properties of ScPd3 and its hydride ScPd3H4 for potential applications in solid-state hydrogen storage. This analysis is presented using the CASTEP software, based on density functional theory (DFT). Our calculations show that geometric optimization confirmed the experimental lattice parameters of these materials and the stability of the studied structures after hydrogen incorporation. The calculated electronic structure revealed that ScPd3 and ScPd3H4 exhibit metallic character, indicating that hydrogen insertion does not affect the nature of the chemical bond. However, this study shows that hydrogen influences certain optical properties (polarizability and absorption). The enthalpy of formation (ΔHf) of the ScPd3H4 compound has been calculated and is found to be 37.31 kJ/mol·H2 lower than that of some hydrogen storage materials. This is favorable for stationary hydrogen storage applications.