Exploration of Physical Properties of Sodium‐Based Perovskite Hydrides ANaH
3
(A = Hf, Nb, Pd, Ru) for Hydrogen Storage Applications: First Principles Study
Aug 2026· Advanced Physics Research· 0 citations· 71 references
Abstract
In this work, first‐principles density functional theory (DFT) was used to investigate the structural, mechanical, thermodynamic, electronic, and hydrogen storage properties of sodium hydride perovskites ANaH
3
(A = Hf, Nb, Pd, Ru). All compounds crystallize in a stable cubic perovskite structure with negative formation energies. Ab initio molecular dynamics simulations at 500 K show minimal energy fluctuations, and phonon analysis confirms dynamical stability. Mechanical properties indicate overall stability, with HfNaH
3
, NbNaH
3
, and RuNaH
3
being ductile, while PdNaH
3
is slightly brittle. The calculated Debye temperatures (818.17–945.61 K) suggest high lattice rigidity and thermal stability. Electronic structure results reveal metallic behavior for HfNaH
3
and NbNaH
3
, whereas PdNaH
3
and RuNaH
3
exhibit narrow indirect bandgaps. Density of states analysis indicates strong hybridization between transition metal d and hydrogen s orbitals, reflecting robust metal–hydrogen interactions. Hydrogen storage performance shows gravimetric capacities of 1.48–2.54 wt.% and volumetric capacities of 100.49–118.93 gH
2
L
−
1
, with desorption temperatures of 280.52–369.11 K, indicating favorable low‐temperature hydrogen release. Finally, these findings provide critical insights into the design and optimization of sodium‐based hydride perovskites as efficient and reversible hydrogen storage materials.
The global movement toward sustainable energy has created growing interest in green hydrogen as a key technology for future energy systems. However, the safe and efficient storage of hydrogen remains a significant challenge. In this study, first-principles calculations were used to examine the phase stability, optoelectronic behavior, and hydrogen storage capability of Al-based metal perovskites XAlH
3
(X = Ga, In, and Tl). The main aim of the research was to assess whether these metal perovskite hydrides could be suitable for solid-state hydrogen storage applications. The calculated formation energies and elastic constants confirm that the XAlH
3
compounds are thermodynamically and mechanically stable. In addition, the positive phonon dispersion results show that all three materials are dynamically stable. The electronic band structure analysis indicates that these hydrides have metallic characteristics. Furthermore, the estimated B/G ratio and Cauchy pressure values suggest that the XAlH
3
materials possess ductile behavior. We also investigated the optical responses of XAlH
3
hydrides in detail. The thermal stability of these hydrides was confirmed by the thermodynamic evaluations and AIMD simulations. The calculated gravimetric hydrogen capacity of GaAlH
3
, InAlH
3
, and TlAlH
3
is found to be 3.03, 2.09, and 1.29 wt%, respectively. Furthermore, the calculated volumetric hydrogen storage capacities for GaAlH
3
, InAlH
3
, and TlAlH
3
are 96.66, 86.63, and 82.43 gH
2
/L, respectively. Desorption temperatures for GaAlH
3
, InAlH
3
, and TlAlH
3
are 397.53 K, 555.64 K, and 218.06 K, respectively. Overall, this study indicates that Al-based perovskite hydrides may be promising materials for solid-state hydrogen storage, and the investigation of XAlH
3
hydrides offers a useful pathway for advancing hydrogen storage technologies.
Abdullah Al Mahmud, Jahirul Islam, S. Aldaghfag et al.· Modern physics letters B· 0 citations
First-principles and ab initio molecular dynamics (AIMD) simulations were employed to investigate the physical properties and hydrogen storage properties of novel cubic XHfH3 (X = K, Rb, and Cs) perovskite hydrides. To the best of our knowledge, this is the first theoretical study of these compounds. Negative formation energies (-1.60 to -1.35 eV/atom) confirm their thermodynamic stability, while AIMD simulations demonstrate structural integrity at 300 K and elevated temperatures over 10 ps. Phonon dispersion calculations reveal the dynamical stability of the Rb- and Cs-based compounds through the absence of imaginary phonon modes. Electronic band structure calculations using both GGA-PBE and HSE06 functionals indicate metallic behavior for all hydrides. Mechanical analysis confirms elastic stability and reveals a gradual transition from brittle to ductile behavior with increasing alkali cation size. Optical calculations show metallic characteristics with tunable plasmonic response and absorption behavior. Thermodynamic properties exhibit strong temperature-dependent phonon contributions, reflected in the evolution of enthalpy, entropy, and Gibbs free energy. Among the studied compounds, KHfH3 exhibits the highest hydrogen storage performance, with a gravimetric capacity of 1.35 wt.% and a volumetric capacity of 72 g H2/L. These findings highlight XHfH3 hydrides as promising candidates for hydrogen storage and multifunctional energy-related applications.
Istiak Ahmed Ovi, Tasmi Akter, M. S. Ahmad et al.· ChemPhysChem· 0 citations
First‐principles density functional theory (DFT) computations were conducted to examine the structural, electrical, optical, mechanical, and hydrogen storage properties of the rare‐earth‐based perovskite hydrides XLiH3 (X = Tm, Yb). The cubic structures were optimized in space group Pm3¯m$Pm\bar{3}m$ with approximately equal lattice parameters (∼3.61 Å; ∼47 Å3). The stability of the cubic framework aligns with tolerance and octahedral factor criteria. Thermodynamic stability is evidenced by the negative formation energies of −0.489 and −0.456 eV/atom for TmLiH3 and YbLiH3, respectively. The electronic structure analysis demonstrates metallic characteristics, indicating improved electrical conductivity and efficient charge transfer. The compounds demonstrate strong mechanical, dynamic, and thermal stability, confirmed by standard elastic‐stability assessments, phonon analyses, and ab initio molecular dynamics stability at around 300 K. The evaluation of hydrogen storage reveals gravimetric capacities of 1.69 wt.% for TmLiH3 and 1.65 wt.% for YbLiH3, with substantial volumetric capacities of 107 and 107.1 g H2/L, respectively, and suitable desorption temperatures of 381.36 and 336.69 K.
S. Shahrear, Md Saiduzzaman, Md. Al Momin et al.· Advanced Theory and Simulati...· 0 citations
This study investigates novel hydrogen storage materials Na
2
XH
6
(X = V, Cr and Co) using first-principles density functional theory (DFT) within the GGA-PBE approximation, as implemented in the CASTEP code. The structural, electronic, mechanical, optical and thermal properties are systematically analyzed. Gravimetric capacities (Cwt.%) are 5.88%, 5.81% and 5.45% for Na
2
VH
6
, Na
2
CrH
6
and Na
2
CoH
6
, respectively. Geometry optimization yields stable structures with lattice constants of 7.65Å, 7.50 Å and 7.24Å. Negative formation enthalpies confirm thermodynamic stability, while band structure analysis reveals metallic character. Mechanical stability is verified by calculated elastic constants (C
11
, C
12
and C
44
) satisfying the Born-Huang criteria.
R. Oualaid, Youssef El Bid, N. El Biaze et al.· E3S Web of Conferences· 0 citations
First-principles density functional theory calculations were performed using CASTEP to investigate the physical and hydrogen storage properties of cubic ACaH
3
(A = Be, Mg, Sr, and Ba) hydrides and to determine how A-site cation identity influences their behavior. The optimized lattice constants of BeCaH
3
, MgCaH
3
, SrCaH
3
, and BaCaH
3
are 4.091, 4.193, 4.362, and 4.464 Å, respectively, while the corresponding formation energies are -0.702, -1.031, -1.408, and -1.455 eV/atom, indicating energetically favorable formation relative to the constituent elemental states. All four hydrides exhibit metallic electronic structures, with bands crossing the Fermi level, whereas charge density and population analyses reveal predominantly ionic metal hydrogen bonding with a limited covalent contribution. The cubic elastic stability criteria are satisfied throughout the series, while phonon calculations reveal composition dependent soft modes in the ideal cubic phases at 0 K. BeCaH
3
is the softest and most elastically anisotropic member and is the only ductile compound, whereas SrCaH
3
exhibits the highest shear resistance and stiffness. The gravimetric and volumetric hydrogen storage capacities are, respectively, 5.770 wt.% and 72.93 g H
2
L
-1
for BeCaH
3
, 4.470 wt.% and 67.90 g H
2
L
-1
for MgCaH
3
, 2.295 wt.% and 60.04 g H
2
L
-1
for SrCaH
3
, and 1.663 wt.% and 55.99 g H
2
L
-1
for BaCaH
3
. The corresponding lowest estimated desorption temperatures are 82.680, 150.596, 693.382, and 716.070 K, respectively. Across the series, the increasingly negative formation energy is accompanied by decreasing hydrogen storage capacity and a progressively higher temperature requirement for hydrogen release. Overall, A-site substitution strongly influences the hydrogen storage capacity and thermodynamic requirement for hydrogen release, supporting further experimental evaluation of these ACaH
3
hydrides particularly BeCaH
3
as solid state hydrogen storage materials.
Sahed Mahmud, Md Saiduzzaman, M. N. Khan et al.· Modern physics letters B· 0 citations
Next-generation clean-energy technologies seek efficient solid-state energy storage materials for hydrogen-based energy systems that exhibit thermodynamically stable properties and multifunctional optoelectronic performance. In the current article, the structural, hydrogen-storage, mechanical, electronic, optical, thermodynamic, and photocatalytic properties of the A
2
LuCuH
6
(A = Li, Na, K) cubic double perovskite hydrides are systematically investigated using first principles density functional theory calculations. The optimized lattice constant gradually rises from 7.78 Å in Li
2
LuCuH
6
to 7.94 Å in Na
2
LuCuH
6
and 8.18 Å in K
2
LuCuH
6
, and the bulk modulus gradually reduces from 43.48 to 39.29 GPa, showing gradually increasing lattice softening. Negative formation enthalpies of -43.08, -48.71, and − 54.99 kJ/mol verify their thermodynamic stability. The gravimetric hydrogen-storage capacities are recorded as 2.34, 2.08, and 1.87 wt%, while the volumetric capacities are 21.33, 20.06, and 18.35 gH
2
/L for Li, Na, and K-based compounds, respectively. The computed hydrogen desorption temperatures are 329.61, 372.54, and 420.73 K, which show tunable hydrogen-release behavior. The indirect semiconducting band gaps in the range of 1.46–2.01 eV at ambient pressure with strong optical absorption in the visible-UV range. In addition, the favorable band-edge alignment is indicative of photocatalytic suitability for overall water splitting, and the pressure-dependent thermodynamic parameters indicate lattice rigidity and a decrease in anharmonic effects under compression, which demonstrates the multi-functional energy potential of these hydride perovskites.
Ali Mustafa Khan, M. U. Sohaib, Sikander Azam et al.· Scientific Reports· 0 citations