Theoretical modeling of experimental isotherms for hydrogen storage in La0.9Ce0.1Ni5 alloy.

This research reports the results of an experimental and numerical analysis of the La 0.9 Ce 0.1 Ni 5 alloy's hydrogen absorption and desorption isotherms at three distinct temperatures (T = 313 K, 333 K, and 353 K). We first determined the morphological and structural properties, as well as the hydrogen storage isotherms, of the intermetallic La 0.9 Ce 0.1 Ni 5 experimentally. The experimental isotherms were then compared to a mathematical model based on statistical physical theory. Due to the good agreement between the experimental isotherms and the proposed model, the insertion and release of hydrogen atoms (n α , n β), geometric densities of receptor sites (N αm , N βm), and absorption-desorption energies (P α , P β) were determined. Moreover, thermodynamic functions like enthalpy, entropy, Gibbs free energy, and internal energy were calculated using these parameters. The findings demonstrated that the intermetallic compound's CaCu 5 structure promotes the formation of stable metal hydrides through attractive interactions, ensuring that hydrogen atoms are securely trapped in the metal lattice, thereby enhancing the material's hydrogen storage capacity. • The suggested alloy isotherms were determined experimentally at various temperatures. • A numerical model has been developed to adjust the experimental data of hydrogen storage by the La 0.9 Ce 0.1 Ni 5 alloy. • The numerical and experimental results demonstrate a good agreement. [ABSTRACT FROM AUTHOR]