Research Article

Unveiling the Potential of Ternary Hydrides: An Ab Initio Study on Rb2CaH4 and Cs2CaH4 for Solid-State Hydrogen Storage

Number: 10 June 30, 2026
EN

Unveiling the Potential of Ternary Hydrides: An Ab Initio Study on Rb2CaH4 and Cs2CaH4 for Solid-State Hydrogen Storage

Abstract

Efficient solid-state hydrogen storage remains a pivotal challenge for sustainable energy systems. This study presents a comprehensive first-principles investigation into the structural, electronic, mechanical, and thermodynamic properties of ternary hydrides Rb2CaH4 and Cs2CaH4 using density functional theory. Both compounds are found to crystallize in a thermodynamically stable tetragonal I4/mmm structure. Electronic structure analysis reveals an insulating character with wide band gaps of 3.32 eV and 3.03 eV, respectively, ensuring stability during hydrogen desorption cycles. Mechanical calculations indicate that these hydrides exhibit brittle behavior characterized by mixed ionic-covalent bonding. Crucially, the gravimetric hydrogen storage capacities are determined as 1.88 wt% for Rb2CaH4 and 1.30 wt% Cs2CaH4. While gravimetric values are modest, volumetric capacities (~40-44 g H2/L) align with DOE 2025 targets. Thermodynamic modeling predicts desorption temperatures above 600 K, suggesting these materials are particularly viable candidates for stationary high-temperature thermal energy storage applications rather than mobile uses

Keywords

References

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Details

Primary Language

English

Subjects

Metrology, Applied and Industrial Physics

Journal Section

Research Article

Publication Date

June 30, 2026

Submission Date

January 1, 2026

Acceptance Date

May 21, 2026

Published in Issue

Year 2026 Number: 10

APA
Yamçıçıer, S. (2026). Unveiling the Potential of Ternary Hydrides: An Ab Initio Study on Rb2CaH4 and Cs2CaH4 for Solid-State Hydrogen Storage. International Journal of Chemistry and Technology, 10, 1-12. https://doi.org/10.32571/ijct.1854071
AMA
1.Yamçıçıer S. Unveiling the Potential of Ternary Hydrides: An Ab Initio Study on Rb2CaH4 and Cs2CaH4 for Solid-State Hydrogen Storage. Int. J. Chem. Technol. 2026;(10):1-12. doi:10.32571/ijct.1854071
Chicago
Yamçıçıer, Sümeyra. 2026. “Unveiling the Potential of Ternary Hydrides: An Ab Initio Study on Rb2CaH4 and Cs2CaH4 for Solid-State Hydrogen Storage”. International Journal of Chemistry and Technology, nos. 10: 1-12. https://doi.org/10.32571/ijct.1854071.
EndNote
Yamçıçıer S (June 1, 2026) Unveiling the Potential of Ternary Hydrides: An Ab Initio Study on Rb2CaH4 and Cs2CaH4 for Solid-State Hydrogen Storage. International Journal of Chemistry and Technology 10 1–12.
IEEE
[1]S. Yamçıçıer, “Unveiling the Potential of Ternary Hydrides: An Ab Initio Study on Rb2CaH4 and Cs2CaH4 for Solid-State Hydrogen Storage”, Int. J. Chem. Technol., no. 10, pp. 1–12, June 2026, doi: 10.32571/ijct.1854071.
ISNAD
Yamçıçıer, Sümeyra. “Unveiling the Potential of Ternary Hydrides: An Ab Initio Study on Rb2CaH4 and Cs2CaH4 for Solid-State Hydrogen Storage”. International Journal of Chemistry and Technology. 10 (June 1, 2026): 1-12. https://doi.org/10.32571/ijct.1854071.
JAMA
1.Yamçıçıer S. Unveiling the Potential of Ternary Hydrides: An Ab Initio Study on Rb2CaH4 and Cs2CaH4 for Solid-State Hydrogen Storage. Int. J. Chem. Technol. 2026;:1–12.
MLA
Yamçıçıer, Sümeyra. “Unveiling the Potential of Ternary Hydrides: An Ab Initio Study on Rb2CaH4 and Cs2CaH4 for Solid-State Hydrogen Storage”. International Journal of Chemistry and Technology, no. 10, June 2026, pp. 1-12, doi:10.32571/ijct.1854071.
Vancouver
1.Sümeyra Yamçıçıer. Unveiling the Potential of Ternary Hydrides: An Ab Initio Study on Rb2CaH4 and Cs2CaH4 for Solid-State Hydrogen Storage. Int. J. Chem. Technol. 2026 Jun. 1;(10):1-12. doi:10.32571/ijct.1854071