Study of the physical properties of hydride double perovskite CsD2Nb3H10 (D = Ba and Sr) materials: computational insights for hydrogen storage applications

Abstract

The physical and hydrogen storage capacity properties of perovskite materials are commonly explored using computational strategies. In the current study, the structural, optoelectronic, stability, mechanical, thermodynamic, and hydrogen storage properties of the CsD₂Nb₃H₁₀ (D = Ba and Sr) compounds were investigated and determined for the first time. Using the GGA functional of the PBE method in the CASTEP code, a novel CsD₂Nb₃H₁₀ (D = Ba or Sr) perovskite material was investigated. The results showed that the CsD₂Nb₃H₁₀ (D = Ba or Sr) structure is (a = b ≠ c) tetragonal in phase with a space group of p4/mmm. Owing to its electronic properties, CsD₂Nb₃H₁₀ (D = Ba or Sr) showed a zero-bandgap (0.0 eV) metallic behavior. The perovskite material CsD₂Nb₃H₁₀ (D = Ba, Sr) has volumetric preservation ratios of gravimetric ratios of 5.875 and 6.870 weight percent. Additionally, 69.094 and 75.426 g H₂ per L were noted and deemed appropriate for storage. In order to study light-matter interactions, optical factors were studied. The mechanical attributes of CsD₂Nb₃H₁₀ (D = Ba and Sr), such as their modulus (B, E, and G), mechanical index (6.292 and 1.319), compressibility (0.033 and 0.023 GPa), and elastic anisotropy (9.995 and 0.374), were evaluated. The density (4.757 and 4.452 g m⁻³), minimum thermal conductivity (0.586 and 0.887 W m⁻¹ K⁻¹), melting temperature (638.557 and 734.643 K), and Debye temperature (147.878 and 332.726 K) of the materials were also investigated. This analysis demonstrates the potential utility of CsD₂Nb₃H₁₀ (D = Ba and Sr) for hydrogen storage purposes. We aim to perform experiments on the CsD₂Nb₃H₁₀ (D = Ba, Sr) composite in the coming years to validate current findings and explore additional energy applications, such as photovoltaic catalysis.