Perovskite hydrides XBeH3 (X = Al, Ga, In) for solid-state hydrogen storage applications: First-principles insights into storage capacity, desorption temperature, mechanical, vibrational and optoelectronic characteristics

초록

The creation of advanced, sustainable and green energy technologies significantly relies on the scrutiny of effective hydrogen (H-2) storage substances. Perovskite hydrides with tunable structure, stability and multifunctional characteristics are emerging candidates being reported for hydrogen technologies for storage in solid-state form. In the present exploration, density functional theory (DFT) is used to evaluate the structural, hydrogen-storage, electronic, mechanical, thermodynamic (TD) and optical attributes of XBeH3 (X = Al, Ga, In). The examined variants of hydride materials are all observed to be in a stable cubic lattice, crystallizing in the Pm-3m space group (No. 221). The comprehensive scrutiny of hydrogen storage (HS) traits is conducted for the analysis of the potential of hydrides. The storage capacities (SC) of AlBeH3, GaBeH3 and InBeH3 hydrides are 7.75, 3.70 and 2.38 wt.%, respectively. The desorption temperature for the release of H-2 is reported to be 347, 303 and 251K, for AlBeH3, GaBeH3 and InBeH3, respectively, which is compatible with the optimal effective desorption range (233-358 K). Among these hydrides, AlBeH3 has the best HS performance (7.75 wt.% and 347 K) of the three compositions, suggesting it is promising as an efficient substance for storage technologies. The mechanical analysis of elastic coefficients, elastic moduli, ratios (Pugh and Poisson) and anisotropic parameters demonstrates that XBeH3 hydrides exhibit brittleness with mechanical stability and anisotropy. The electronic parameters and optical aspects reveal that AlBeH3, GaBeH3 and InBeH3 metallic hydrides, paving the way for easier hydrogen desorption. Ab initio molecular dynamics (AIMD) simulation shows variation of total energy versus simulation time, which suggests minimal total energy variation and confirms TD stability. The predicted metrics, such as stability, H-2 SC and desorption aspects, recommend experimental validation and highlight the compatibility of hydrides for advanced solid-state HS systems.

키워드