The magneto-mechanical hysteresis damping of Fe-Ga alloys is inversely proportional to internal stress. However, the mechanism by which residual stress influences magneto-mechanical hysteresis damping remains unclear. In this study, an Fe83Ga17 alloy with a < 001 > crystallographic orientation was selected as the research subject. The nanoindentation method was employed to determine the residual stress of alloys subjected to different heat-treatment processes. After characterizing the phase structure, magnetostriction coefficient, and Young's modulus, the effects of residual stress on magneto-mechanical hysteresis damping were investigated by analyzing changes in residual stress and damping of samples after various heat treatments. The results show that two samples-one quenched at 730 degrees C and then annealed at 300 degrees C, and the other only quenched at 730 degrees C-both exhibit uniform phase structures. Although the former sample exhibits a lower magnetostriction coefficient and Young's modulus than the latter, its residual stress is reduced by 98% compared to the latter, leading to an 84% increase in magneto-mechanical hysteresis damping, with the total damping value reaching 0.078. These findings provide a design basis for the application of Fe-Ga alloys in devices such as precision structural vibration reduction and vibration energy harvesting.

This study investigated the relationship between Mn segregation, damping capacity, and mechanical properties of a Mn-Cu damping alloy after aging at different temperatures. The results showed that after aging, the alloy underwent spinodal decomposition, forming Mn-segregated regions, while alpha-Mn precipitates appeared at the grain boundaries. The microstructure resulting from spinodal decomposition promoted martensitic transformation, created twin boundaries, and enhanced damping capacity. As the aging temperature increased, the Mn content in the Mn-rich regions gradually rose, thereby raising the martensitic transformation temperature. The twin density first increased and then decreased, which may be attributed to the precipitation and broadening of the alpha-Mn phase along the grain boundaries of the Mn-rich regions when the aging temperature was too high. At an aging temperature of 425 degrees C, the tan delta reaches a maximum of 0.05, and the martensitic transformation temperature reaches 100 degrees C, at which point the tan delta remains 0.04. After aging at 425 degrees C, a preferred orientation along <001> develops. The [001] orientation has the largest Schmid factor, which is most favorable for the reversible motion of twin boundaries under external stress, thus achieving the highest energy dissipation. To summarize, by promoting the creation of fine {011} twins by means of spinodal decomposition and by increasing the [001] oriented grain fraction through texture development, aging enhances the damping properties of the Mn-Cu alloy. In particular, the aging at 425 degrees C can provide the best combination of the microstructure and texture conditions, providing the highest damping performance in a wide temperature range.

The development of high-entropy alloys (HEAs) for hydrogen storage is hopeful for addressing critical limitations of conventional metal hydrides, such as high activation barriers, limited capacity, and poor cycling stability. Here, we report the novel AB(2)-type (A = Ti, Zr; B = Cr, Mn, Fe, Co, Ni) C14 Laves phase HEAs, namely TiZrCrFeCoNi, TiZrCrMnFeCo, and TiZrCrMnFeNi, integrating thermodynamic calculations, arc-melting synthesis, microstructural characterization, hydrogen storage testing, and first-principles calculations. It is shown TiZrCrFeCoNi has very low affinity for hydrogen, which is mainly attributed to the relatively small cell volume. TiZrCrMnFeCo is able to absorb and release 0.94 wt% hydrogen rapidly at room temperature after a 400 degrees C thermal activation. Replacing Co with Ni atoms has a significant effect of improving hydrogen storage capacity. Strikingly, TiZrCrMnFeNi alloy, with outstanding kinetic and excellent cycling performance, can reversibly absorb and desorb hydrogen at room temperature with a capacity of 1.66 wt% without any activation treatment. Additionally, the ground-state structural and electronic properties of AB(2)-type HEAs were clarified by firstprinciples calculations.

The incorporation of transition metal Ni and rare-earth elements La and Y into Mg-based alloys significantly enhances hydrogen storage performance through synergistic effects. To optimize storage capacity and glass-forming ability (GFA), a Mg90La2Y2Ni6 alloy was designed and synthesized via induction casting and melt spinning. The amorphous alloy was further subjected to crystallization annealing at 400 °C to obtain a crystallized alloy. Structural analyses (XRD, SEM, HRTEM) revealed that the cast alloy comprised Mg, Mg2Ni, La2Mg17, and YNi3 phases. Melt spinning produced amorphous–nanocrystalline composites, with the amorphous fraction increasing with spinning rate. The crystallized alloy exhibited a phase composition similar to the cast alloy, but with finer, uniformly dispersed precipitates that provided enhanced diffusion pathways. Hydrogen storage properties were evaluated by Sievert apparatus and DSC. The crystallized alloy demonstrated markedly improved hydrogen absorption/desorption kinetics compared with the cast alloy. Specifically, the desorption activation energy decreased from 67.84 kJ/mol (cast) to 58.56 kJ/mol (crystallized, 30 m/s spinning rate). In addition, the initial hydrogen desorption temperature was reduced from 323.5 °C to 288.2 °C. Thermodynamic analysis further confirmed a decrease in desorption enthalpy, indicating reduced hydride stability. Overall, the melt spinning–crystallization annealing route effectively tailors the microstructure and thermodynamics of Mg-based alloys, leading to lower activation energy, reduced desorption temperature, and enhanced hydrogen storage performance.

The inherent drawbacks of sluggish kinetics and excessive thermodynamic stability limit the practical deployment of Mg-based hydrogen storage materials. In this study, multi-component Mg90La2Ce2Ni3Al3-xBax (x = 0, 0.3, 0.6, 0.9, 1.2) alloys were fabricated. X-ray diffraction analyses reveal that Ba-containing alloys develop a multi-phase structure comprising Mg, La2Mg17, CeMg12, AlNi, and the Mg17Ba2 phase. The Mg17Ba2 induces a reversible transformation between Ba2Mg7H18 and Ba2MgH6, which occurs alongside the primary hydrogenation and dehydrogenation reactions of MgH2 and Mg. Importantly, the generated LaH3, CeH2.73, and Ba2Mg7H18/ Ba2MgH6 hydrides, in conjunction with the AlNi phase, introduce numerous phase boundaries within the alloys. This structural change creates numerous nucleation sites for MgH2/Mg and diffusion channels for hydrogen atoms. Consequently, the activation and hydrogen absorption and desorption properties of the alloys are significantly enhanced. Kinetic analysis using the Johnson-Mehl-Avrami-Kolmogorov model demonstrates that Ba doping accelerates the growth of MgH2 and facilitates the diffusion of hydrogen atoms during hydrogenation. Furthermore, both the calculated dehydrogenation activation energy and the peak dehydrogenation temperature of the alloys significantly decrease with the introduction of Ba element, confirming its pivotal role in enhancing the performance of Mg-based alloys.

The application of Mg-based hydrogen storage materials is limited by their high thermodynamic stability and sluggish kinetics. In this work, alkaline-earth elements are incorporated into multi-component Mg90La2Ce2-Ni3Al1.8M1.2 (M = Ca, Sr, Ba) alloys to promote the in situ formation of catalytic hydride phases. Activation induces phase transformations: the Ca1.2 alloy forms stable CaH2, while Sr1.2 and Ba1.2 develop the reversible hydride systems SrMgH4/SrH2 and Ba2Mg7H18/Ba2MgH6, respectively. These hydrides work synergistically with the LaH3, CeH2.73, and AlNi phases, significantly enhancing the reaction kinetics. Among the alloys, Sr1.2 exhibits the best overall performance. At 633 K, the time required to reach a 5 wt% H2 capacity during hydrogenation is 385 s for Ca1.2, 90 s for Sr1.2, and 750 s for Ba1.2; the corresponding dehydrogenation times are 190 s, 127 s, and 165 s, respectively. Furthermore, the peak dehydrogenation temperatures are 689.7 K for Ca1.2, 622.5 K for Sr1.2, and 620.5 K for Ba1.2, highlighting the effective enhancement provided by the Sr-and Babased hydrides.

Mg95-xEuxNi5 (x = 0-4) alloys were prepared by melt-spinning to clarify the role of Eu substitution in Mg-Ni hydrogen storage alloys. XRD and SEM-EDS reveal that Eu addition converts the binary Mg-Mg2Ni system into a multiphase structure (Mg, Mg2Ni, Eu2Mg17), the TEM and SAED characterizations further confirmed this result. Moderate Eu levels (x = 1-2) refine the microstructure and promote fine Eu-based intermetallic, whereas excessive Eu (x >= 3) leads to coarse dendrites and phase segregation. P-C-T and kinetic measurements show that appropriate Eu doping enhances the activation behavior, lowers plateau pressure, reduces hysteresis, and accelerates hydrogen absorption/desorption. The x = 1-2 alloys exhibit the best kinetics and the lowest activation energies (86.31, 87.31 kJ & sdot;mol-1) while retaining over 90% capacity after 50 cycles. DFT calculations indicate that Eu incorporation increases the density of states near the Fermi level, enhances charge polarization, and reduces hydrogen dissociation energy (-1.4125 eV), thus facilitating H2 activation and diffusion. These results show that controlled Eu doping effectively tailors the microstructure and electronic structure of Mg-Ni alloys, leading to improved thermodynamics, kinetics, and cycling durability.

The inherent limitations of Mg-based hydrogen storage materials, such as sluggish kinetics and high thermodynamic stability, have hindered their practical application. To address these challenges, a series of multi-component Mg90La2Ce2Ni3Al3-xSrx (x = 0, 0.3, 0.6, 0.9, 1.2) alloys were synthesized. X-ray diffraction analysis shows that the alloys are composed of a main Mg phase and secondary phases of La2Mg17, CeMg12, and AlNi, while the Sr-containing alloys also contain a Mg17Sr2 phase. The Mg17Sr2 phase promotes a reversible transformation between SrMgH4 and SrH2, which occurs simultaneously with the MgH2/Mg reaction. Importantly, the generated hydrides LaH3, CeH2.73, and SrMgH4/SrH2, together with the AlNi phase, introduce numerous phase boundaries that provide additional nucleation sites for Mg/MgH2 and create improved pathways for hydrogen diffusion. Furthermore, increasing Sr incorporation reduces both the dehydrogenation activation energy and the peak dehydrogenation temperature. Specifically, as Sr content rises from 0 to 1.2, the dehydrogenation activation energy decreases from 108.18 kJ/mol to 80.19 kJ/mol, and the peak dehydrogenation temperature drops from 676.5 K to 620.5 K. These comprehensive results demonstrate that the addition of Sr can effectively enhance the hydrogen storage performance of Mg-based alloys.

Fe-Ga alloys exhibit significant potential for developing multifunctional integrated devices that combine low-field large magnetostriction with vibration-damping capabilities. Substituting Ga with inexpensive Al is an effective strategy to reduce production costs. However, the phase transformation behavior and the associated property modulation mechanisms in ternary Fe-Ga-Al alloys remain inadequately understood. In this study, a <001>-textured Fe₈₃Ga₁₄Al₃ alloy was employed to investigate phase evolution behaviors and their effects on magnetostriction and damping properties during aging at 300–500 °C. Experimental results confirm that magneto-mechanical hysteresis damping (MMHD) is the primary damping mechanism in the alloy. Specimens aged at 300 °C contain numerous fine L6₀ nanoprecipitates with high coherency relative to the matrix, achieving superior overall properties with a saturation magnetostriction of 198 × 10⁻⁶, MMHD of 0.050, and total damping of 0.068, thereby attaining a well-balanced combination of magnetostriction and damping performance. Higher aging temperatures induce gradual coarsening of the L6₀ phase and partial phase transformation toward the L1₂ phase, which collectively degrade both the magnetostriction and damping properties. This study established a correlation among aging conditions, phase composition, and functional properties, providing reliable theoretical guidance and experimental reference for the development of low-cost, high-performance magnetostriction-damping integrated alloys.

This study investigated the influence of Mn content (70 wt.%, 75 wt.%, and 80 wt.%) on the microstructure, mechanical properties and damping capacity of Mn-Cu alloys using X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), mechanical testing and dynamic mechanical analysis (DMA). The results indicate that during cooling after aging, the Mn-Cu alloy undergoes martensitic transformation, resulting in a dual-phase structure of fcc and fct. The 70 wt.% Mn alloy exhibits a mixed-grain structure with mostly long, straight twin bands, while the 75 wt.% and 80 wt.% Mn alloys consist of fine equiaxed grains with mostly intersecting twin bands. The microstructure determines the properties of the alloy. As the Mn content increases, the mechanical properties initially increase and then decrease, and the 75 wt.% Mn alloy has the best mechanical performance (UTS = 534 MPa, YS = 263 MPa). In contrast, the damping capacity shows a decreasing trend, and the 70 wt.% Mn alloy exhibits the best damping capacity (tanδ = 0.064). The main damping peak of tanδ in Mn-Cu alloys is derived from the relaxation of the twin boundaries, and the less obvious secondary peak is the internal friction peak of martensitic transformation.

To address the poor microwave absorption performance of single-component materials, rGO/Fe3O4/PPy and rGO/Fe3O4/PEDOT ternary nanocomposites with dual electromagnetic loss mechanisms were prepared via microemulsion polymerization, resulting in significantly enhanced microwave absorption properties. Analysis of their structural morphology and microwave absorption performance reveals that, in addition to dipole polarization induced by internal defects within the composites, conduction loss arising from conductivity differences between components, and interfacial polarization effects among multiple constituents, the granular morphology of PEDOT facilitates more effective integration with rGO and Fe3O4 compared to the film-like structure of PPy. This enhanced integration increases the number of microscopic interfaces within the rGO/Fe3O4/PEDOT ternary nanocomposite and augments its internal conductive network, thereby intensifying both conduction loss and interfacial polarization effects. Consequently, the rGO/Fe3O4/PEDOT composite exhibits the highest internal relaxation loss, the greatest dielectric loss value, and optimal microwave absorption performance. Its minimum reflection loss reaches -83.16 dB at a matching thickness of 3.4 mm and a frequency of 7.20 GHz, with an effective absorption bandwidth (reflection loss below -10 dB) of 4.58 GHz (ranging from 5.12 to 9.70 GHz).

Magnesium hydride (MgH2) is a promising solid-state hydrogen-storage material because of its high theoretical hydrogen capacity, but its practical application remains limited by sluggish sorption kinetics and high thermodynamic stability. In this work, a dual-phase Mg/MgH2-Ti3C2Tx composite was prepared by hydrogenation-assisted reactive ball milling using metallic Mg as the starting material. The optimized Mg-5 wt% Ti3C2com-posite exhibits a dehydrogenation onset temperature of 173 degrees C, which is 113 degrees C lower than that of the Ti3C2-free sample, and releases 6.20 wt% H2within 1 min at 300 degrees C. It also shows enhanced hydrogen absorption over 100-300 degrees C. Kinetic analysis indicates that Ti3C2addition reduces the apparent dehydrogenation activation energy from 118.8 to 71.39 kJ Mol-1. Structural characterizations reveal a defect-rich microstructure with uniformly dispersed Ti-containing species and abundant Mg/MgH2heterointerfaces. Comparative experiments further show that etched Ti3C2is more effective than its parent Ti3AlC2MAX phase in promoting hydrogen sorption. XPS and DFT results support the important role of Ti-centered species in the hydrogen sorption process. In addition, the Mg-5 wt% Ti3C2composite retains 90.3% of its dehydrogenation capacity after 30 cycles at 300 degrees C. These results show that hydrogenation-assisted reactive milling is an effective route for constructing active Mg/MgH2-Ti3C2composites with improved hydrogen-storage performance

Slow hydrogen absorption/desorption kinetics and high thermal stability are regarded as major setbacks for the real application of Mg-based hydrogen storage alloys. Overcoming these shortcomings, the Mg25-xYxNi10 (x = 0, 1, 3, 5, 7) alloys with nanocrystalline and amorphous structures were synthesized by melt spinning technology to improve their hydrogen absorption/desorption properties. The dehydrogenation activation energy of the alloy was estimated using the Arrhenius and Kissinger methods. The starting dehydrogenation temperature and thermodynamic parameters (Delta H, Delta S) of Y partially substituted Mg alloys prepared by melt spinning technique were significantly decreased. The partial substitution of Y for Mg is the main reason for the decrease in the hydrogen storage capacity of Mg-Y-Ni alloys, and the hydrogen absorption capacity increases in the beginning and then declines with the spinning rate rising. Partial substitution of Mg by Y and melt spinning resulted in a significant improvement in the dehydrogenation kinetics of the alloy along with a slight decrease in the hydrogen absorption kinetics. The dehydrogenation activation energy of the alloys decreased significantly with increasing Y content and spinning rate, when the spinning rate was increased from 0 m/s to 30 m/s, the Ede decreased from 68.61 kJ/mol to 53.84 kJ/mol, and when the Y content was increased from 0 to 7, the Edek-value of the alloy decreased from 65.96 kJ/mol to 48.86 kJ/mol. The decrease in dehydrogenation activation energy was also considered to be the main reason for the enhanced dehydrogenation kinetics of the alloys.

V2C MXene has shown potential as a catalyst for Mg-based hydrogen storage, but its catalytic role in the complete Mg-* MgH2-* Mg cycle and its distinction from the corresponding V2AlC MAX precursor remain insufficiently clarified. Herein, Mg-V2C composites were prepared from metallic Mg by hydrogen-assisted ball milling, with Mg-V2AlC composites fabricated under identical conditions as a benchmark. Structural analyses show that V2C is fragmented during milling, producing an interface-rich microstructure composed of Mg/MgH2matrices, dispersed V-containing domains, and disordered V-C-related components. Compared with V2AlC, V2C more effectively promotes Mg hydrogenation during milling and MgH2dehydrogenation, leading to a higher MgH2 fraction, lower dehydrogenation temperature, and faster hydrogen sorption kinetics. Among the investigated compositions, Mg-7 wt% V2C exhibits the most balanced overall performance, delivering high reversible capacity and rapid sorption kinetics. Its apparent dehydrogenation activation energy is reduced from 118.8 kJ mol-1H2 for pristine Mg to 62.34 kJ mol-1H2, much lower than that of Mg-7 wt% V2AlC (106.01 kJ mol-1H2). PCT analysis indicates that V2C mainly enhances hydrogen sorption kinetics without markedly altering absorption thermodynamics, while avoiding the Al-induced hydride stabilization observed in V2AlC. Kinetic fitting suggests R2-type apparent dehydrogenation behavior for Mg-V2C, distinct from the A2-type behavior of pristine Mg and Mg-V2AlC. XPS and DFT results further support the role of V2C-derived surfaces in hydrogen activation. These results demonstrate the MXene-specific catalytic advantage of V2C over V2AlC for Mg-based hydrogen storage.

To lower the hydrogen desorption temperature of Mg-base alloys, the microstructural evolution, hydrogen absorption/desorption thermodynamics and kinetics of Mg92La1.5Ce1.5Ni5-xAlx (x = 0, 0.5, 1.0, 1.5) alloys are studied. The x = 0 alloy consists of Mg and REMgx main phases and Mg2Ni minor phase. Partial Al substitution for Ni induces Mg2Ni decomposition into AlNi and Al3.16Mg1.84, gradually eliminating Mg2Ni phase. Al also reacts with REMgx to generate REAla phase. Among the Al-containing phases, only AlNi remains stable during cycling and delivers sustained catalysis. Accordingly, the activation energy decreases significantly from 110.2 kJ mol-1 (x = 0) to 92.4 kJ mol-1 (x = 1.0), reducing the hydrogen desorption peak temperature by 23-26 degrees C. Moreover, the enthalpy change also reaches the minimum at x = 1.0, weakening hydride stability. The work provides a rational element design strategy for in-situ introducing catalytic phase to enhance the hydrogen storage performance of Mg-based alloys.

ABSTRACT To address the poor microwave absorption performance of single‐component materials, rGO/Fe 3 O 4 /PPy and rGO/Fe 3 O 4 /PEDOT ternary nanocomposites with dual electromagnetic loss mechanisms were prepared via microemulsion polymerization, resulting in significantly enhanced microwave absorption properties. Analysis of their structural morphology and microwave absorption performance reveals that, in addition to dipole polarization induced by internal defects within the composites, conduction loss arising from conductivity differences between components, and interfacial polarization effects among multiple constituents, the granular morphology of PEDOT facilitates more effective integration with rGO and Fe 3 O 4 compared to the film‐like structure of PPy. This enhanced integration increases the number of microscopic interfaces within the rGO/Fe 3 O 4 /PEDOT ternary nanocomposite and augments its internal conductive network, thereby intensifying both conduction loss and interfacial polarization effects. Consequently, the rGO/Fe 3 O 4 /PEDOT composite exhibits the highest internal relaxation loss, the greatest dielectric loss value, and optimal microwave absorption performance. Its minimum reflection loss reaches ‐83.16 dB at a matching thickness of 3.4 mm and a frequency of 7.20 GHz, with an effective absorption bandwidth (reflection loss below ‐10 dB) of 4.58 GHz (ranging from 5.12 to 9.70 GHz).

Magnetic refrigeration is a promising technology capable of achieving sub-Kelvin temperatures without using 3He. However, conventional magnetocaloric materials suffer from drawbacks such as high driving magnetic fields, low magnetic entropy change (GSM), and structural instability, limiting their practical application. In this work, KGdF4 with different crystal structures was synthesized, and the structure dependence of the magnetocaloric effect (MCE) was investigated. Notably, in the cubic KGdF4 (C-KGdF4), the chemical disorder of Gd3+/K+, increases the Gd3+-Gd3+ distance and weakens the dipolar interactions, and thus leads to a large -GSM = 30.5 J kg- 1 K- 1 at 1.3 K at the magnetic field change of 10 kOe, which is more than three times of that of the commercial Gadolinium Gallium Garnet (Gd3Ga5O12, GGG) under the same conditions. Furthermore, the magnetic ordering temperature of 0.6 K of the C-KGdF4 is lower than most reported Gd-based magnetocaloric materials. These excellent magnetocaloric performances suggest that C-KGdF4 is a highly promising candidate for ultra-lowtemperature magnetic refrigeration.

MXenes, with their unique layered structures and exceptional physicochemical properties, have emerged as highly promising materials for solid-state hydrogen storage. This review provides a comprehensive analysis of MXenes' intrinsic hydrogen storage capabilities and their catalytic effects on solid-state hydrogen storage materials. It begins with an overview of MXenes' fundamental properties and synthesis methods, followed by an in-depth examination of their intrinsic hydrogen storage performance, summarizing both theoretical calculations and experimental findings. Key attributes, such as high hydrogen storage capacities and reversible adsorption-desorption characteristics, are highlighted. The review also explores the catalytic role of MXenes in improving the hydrogen storage performance of light metal hydrides and complex hydrides, particularly in reducing dehydrogenation temperatures and enhancing reaction kinetics. Recent advancements in MXene-facilitated hydrogen storage are summarized, and insights into future research directions are presented to optimize their use in efficient hydrogen storage systems. While MXenes hold significant potential for advancing solid-state hydrogen storage technologies and promoting hydrogen as a clean energy carrier, challenges remain, including complex synthesis processes, limited long-term stability, and sensitivity to environmental conditions. Furthermore, structural and compositional variations in MXenes can significantly influence their catalytic activity, necessitating deeper investigations into the kinetics of hydrogen absorption and release. This review consolidates the latest research progress and outlines strategies to address these challenges, aiming to enhance the practical application of MXenes in solid-state hydrogen storage systems.

The development of ultra-low-temperature magnetocaloric materials (MCMs) is crucial for advanced cryogenic refrigeration technologies. Rare-earth fluorides exhibit promising magnetocaloric properties, but the high magnetic ordering temperatures (T0) limit their performance below 2 K. Single-phase KLnF4 (Ln = Tb, Dy, Ho, Er, Tm) compounds with a trigonal structure were successfully synthesized by introducing the diamagnetic K* ions into LnF3 via solid-state sintering. Structural analysis confirms that the K* incorporation increases the distance between Ln3+ ions, suppressing dipolar interactions and reducing T0 to below 2 K. Notably, KHoF4 exhibits a 16.5 % higher magnetic entropy change (-Delta SM) than HoF3, attributed to the lower magnetic anisotropy of the trigonal KHoF4 with higher symmetry. The effects of these two aspects overcome the negative impact caused by the decrease of the magnetic ion concentration. These findings demonstrate that K* incorporation is a dualfunctional strategy for simultaneously modulating transition temperatures and magnetocaloric performance of rare-earth fluorides. This work provides a scalable approach to designing ultra-low-temperature MCMs with various refrigeration windows.

To enhance the rates of hydrogen absorption and desorption in magnesium-based alloys while preserving their substantial hydrogen storage capacity, researchers have incorporated rare earth elements like lanthanum (La) and yttrium (Y), as well as the transition metal nickel (Ni). This combination is designed to destabilize magnesium-hydrogen bonds, thereby enhancing the kinetics of both hydrogenation and dehydrogenation. These elements work together synergistically, accelerating these processes to optimize alloy performance. Additionally, indium (In) is introduced to form a solid solution with the magnesium matrix, aiming to adjust the thermodynamic properties of the alloy. This adjustment influences the formation and stability of the Mg(In) solid solution, thereby maximizing hydrogen storage capabilities. Indium plays a crucial role in fine-tuning the behavior of alloy under different conditions, offering a novel strategy for enhancing hydrogen storage performance. The as-cast alloys Mg90La2Y2Ni6-xInx (x = 0, 0.6, 0.9, 1.2) were subjected to characterization using X-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM) with the objective of investigating phase transformations and structural evolution both before and after hydrogenation. The results indicate the presence of various phases, including Mg, Mg2Ni, La2Mg17, and YNi3. The addition of indium results in the formation of Mg(In) and Mg2Ni(In) solid solutions, which cause lattice contraction in Mg and lattice expansion in Mg2Ni. The isothermal and non-isothermal hydrogen absorption and desorption kinetics were investigated using a Sievert apparatus and differential scanning calorimetry (DSC). The findings indicate that the hydrogen absorption capacity of the alloys reaches 5 wt% at temperatures between 260 degrees C and 360 degrees C, with complete hydrogen desorption achievable at 260 degrees C. Among these, the Mg90La2Y2Ni4.8In1.2 alloy exhibits the optimal hydrogen desorption capacity. As the concentration of indium increases, the initial dehydrogenation temperature decreases from 323.5 degrees C to 282.3 degrees C. The calculations indicate that the absolute enthalpy change for hydrogen desorption decreases from 77.53 kJ/mol to 74.34 kJ/mol, suggesting that the addition of indium effectively reduces the thermal stability of hydrides in the alloy. Additionally, the incorporation of indium coarsens the alloy microstructure, leading to a reduction in the activation energy for hydrogen release to 68.97 +/- 3.37 kJ/mol. This modification enhances the practical applicability of Mg-based alloys for hydrogen storage by facilitating hydrogen desorption under milder conditions.