Hydrogen Storage Applications Research Articles

Multi-objective optimisation of ionic liquid parameters for hydrogen compressors by Taguchi and grey relational analysis methods

The ionic liquid compressor developed in recent decades possesses a prospective application for hydrogen storage. The design of this new compressor considering multiple design parameters and objectives is critical for product development. This study investigated the percentage contribution of four design parameters of the ionic liquid to compressor performance by Taguchi and ANOVA. A two-objective optimisation was conducted to identify the near-optimal setting of ionic liquid parameters combining the Taguchi and grey relational analysis (GRA) methods considering both the liquid mass taken off and the specific energy consumption. It was found that the liquid height was the most influential parameter with percentage contributions of 84.65 % and 90.08 % to the liquid mass taken off and specific energy consumption, respectively. The optimal setting is obtained as the liquid height of 15 mm, liquid density of 1600 kg/m3, liquid viscosity of 50 mPa∙s and surface tension of 0.052 N/m.

Utilizing Nanostructured Materials for Hydrogen Generation, Storage, and Diverse Applications.

The rapid advancement of refined nanostructures and nanotechnologies offers significant potential to boost research activities in hydrogen storage. Recent innovations in hydrogen storage have centered on nanostructured materials, highlighting their effectiveness in molecular hydrogen storage, chemical storage, and as nanoconfined hydride supports. Emphasizing the importance of exploring ultra-high-surface-area nanoporous materials and metals, we advocate for their mechanical stability, rigidity, and high hydride loading capacities to enhance hydrogen storage efficiency. Despite the evident benefits of nanostructured materials in hydrogen storage, we also address the existing challenges and future research directions in this domain. Recent progress in creating intricate nanostructures has had a notable positive impact on the field of hydrogen storage, particularly in the realm of storing molecular hydrogen, where these nanostructured materials are primarily utilized.

Sustainable stationary hydrogen storage application selection with interval-valued intuitionistic fuzzy AHP

The transition to a hydrogen-based economy necessitates a comprehensive evaluation of different hydrogen storage options, considering their sustainability performance. This study innovatively applies the Interval-Valued Intuitionistic Fuzzy Analytic Hierarchy Process (IVIF-AHP) to evaluate and compare four hydrogen storage options: Compressed Hydrogen Gas (CHG), Cryogenic Liquid Hydrogen (CLH), Metal Hydride (MH), and Underground Hydrogen (UH). The evaluation criteria are derived from four dimensions of sustainability: economic, environmental, social, and technical performance, each further decomposed into sub-criteria. The study's novelty lies in using a novel intuitionistic fuzzy AHP, offering a more nuanced and robust understanding of the trade-offs between the various options and effectively capturing the vagueness and subjectivity inherent in human decision-making. Through this methodology, CHG emerged as the most promising option with a preference score of 0.487, closely followed by UH with a score of 0.453. The lowest preference score was accorded to MH, with a score of 0.301. These quantitative insights underscore the relative sustainability performance of each technology under the defined criteria. The findings contribute to the growing body of literature on sustainable hydrogen storage, providing policymakers and practitioners with a multicriteria decision-making tool that captures the complexity of sustainability considerations. This study underlines the critical role of holistic, multicriteria evaluations in advancing sustainable hydrogen storage. It encourages further exploration and validation of its approach in different contexts and with updated technological advancements.

Computational study of effects of doping Ni and Pd on CoAl for hydrogen storage capacity, elastic and electronic properties

Intermetallic compounds in B2 structure which have low density, fracture, and high strength have important applications in different engineering applications. For energy storage apparatus, the researchers have investigated new materials to improve effective efficiency in energy storage devices such as batteries and green energy technologies. The investigation of transition metal–aluminide alloys has increased due to their attractive elastic features. Like many hydrogen storage alloys, B2-type hydrogen storage alloys such as ZrCo utilize the systems of hydrogen storage in atomic gaps. If hydrogen atoms settle in the interstitial spaces, lattice expansion forms due to lattice distortion. Since plastic and elastic deformations change pressure and temperature, they are important for the material during hydrogen desorption and absorption. According to the literature, element doping effects boost hydrogen storage sufficiency. The effects of Ni- and Pd-substituted dopants on hydrogen storage, electronic and elastic features of a Cobalt-Aluminum alloy were performed using the first-principles calculations with and without spin-polarized configurations. Obtained lattice parameters for Co8Al8 are good agreement with literature values. Interstitial H doping has changed the crystal structure from cubic (BCC) to tetragonal. It is concluded that all investigated CoAl alloys included H doping has negative formation energies showing thermodynamically stabilities. All investigated alloys are stable mechanically and dynamically. Doping of H2 atoms to CoAl changes from a brittle to ductile nature. Also, Ni contributions improve ductility behavior to improve the cycle performance of the Co7NiAl8 and Co8Al7Ni alloy. It can be concluded from electronic band structure that they exhibite metallic behavior. Our obtained gravimetric and volumetric capacities which are comparable with B2 hydrogen storage material such as ZrCo, FeAl, indicate that CoAl alloys may be suitable for hydrogen storage applications.

Ab initio insight into the physical properties of MgXH3 (X = Co, Cu, Ni) lead-free perovskite for hydrogen storage application.

Renewable energy systems are vital for a sustainable future, where solid-state hydrogen storage can play a crucial role. Perovskite hydride materials have attracted the scientific community for hydrogen storage applications. The current work focuses on the theoretical study using density functional theory (DFT) to evaluate the characteristics of MgXH3 (X = Co, Cu, Ni) hydrides. The structural, vibrational, electronic, mechanical, thermodynamic, and hydrogen storage properties of these hydrides were investigated. The equilibrium lattice parameters were calculated using the Birch-Murnaghan equation of state-to-energy volume curves. The elastic constants (Cij) and relevant parameters, such as Born criteria, were calculated to confirm the mechanical stability of the hydrides. The Cauchy pressure (Cp) revealed brittle or ductile behavior. The outcomes of the Pugh ratio, Poisson ratio, and anisotropy were also calculated and discussed. The absence of negative lattice vibrational frequencies in phonon dispersion confirmed the lattice's dynamic stability. The heat capacity curves of thermodynamic properties revealed that hydrides can conduct thermal energy. The metallic character and ample interatomic distances of hydrides were confirmed by the band structure and population analysis, which confirmed that hydrides can conduct electrical energy and adsorb hydrogen. The density of state (DOS) and partial DOS unveiled the role of specific atoms in the DOS of the crystal. The calculated gravimetric hydrogen storage capacity of MgCoH3, MgCuH3, and MgNiH3 hydrides was 3.64, 3.32, and 3.49wt%, respectively. Our results provide a deeper understanding of its potential for hydrogen storage applications through a detailed analysis of MgXH3 (X = Co, Cu, Ni) perovskite hydride material.

Enhancement of hydrogen storage using functionalized MoSe2/Graphene monolayer and bilayer systems: DFT study

Utilizing the spin-polarized density-functional theory (DFT), we present an investigation of the adsorption properties of hydrogen-gas molecules on ten different substrates, which are based upon defected and TM-doped MoSe2 monolayer (ML) and MoSe2/graphene bilayer (BL) systems (TM = Ni, Cu). Particularly, Ni, and Cu substitutional doping at Se site showed distinct high H2 uptake capacity and thus to be good candidates for H2 storage. On these latter catalysts, H2 molecule exhibited physisorption with moderate respective energies Eads = −0.307 and −0.362 eV, attributed to the enhancement in electric dipole moment and spin splitting (magnetism) induced in the substrate. The desorption processes of the H2 molecule are found to cost energies of about 0.46 and 0.44 eV, respectively. Moreover, the H2 molecule can move parallel to the substrate after crossing potential barriers of 0.56 and 0.65 eV, respectively. Furthermore, the gravimetric uptake density can further be improved by increasing the dopants concentrations. For instance, by increasing the number of Ni dopants from one to two atoms in the computational sample 4 × 4 PCs of MoSe2 ML, the gravimetric density raises from 1.28 wt% to 3.6 wt% (almost triple). This should corroborate the candidacy of TM-doped @Se MoSe2 for hydrogen storage applications. PAC Numbers31.15.E; 68.43.-h; 68.43.Mn; 68.65.Pq; 73.43.Cd; 75.70.Rf.

Hydrogen storage mechanism of metal–organic framework materials based on metal centers and organic ligands

AbstractThe effective storage and utilization of hydrogen energy is expected to solve the problems of energy shortage and environmental pollution currently faced by human society. Metal–organic framework materials (MOFs) have been shown by scientists to be very potential hydrogen storage materials. However, the current design methods and strategies for MOFs are still generally in the trial‐and‐error stage, and the research works are at the overall level. To solve the problems of directional design and rational construction of new MOFs, this work uses the principles and methods of coordination chemistry and crystal engineering to carry out the theoretical design and mechanism research of new MOFs for high‐efficiency hydrogen storage application scenarios. In this study, the structures selected for theoretical calculation were divided into two types: different ligands for the same metal (IRMOFs, MOF‐205, and DUT‐23‐Zn) and different metals for the same ligand (DUT‐23‐M [(M = Co, Ni, Cu, and Zn]). The model construction process, hydrogen loading with temperature, specific surface area, hydrogen adsorption energy, charge density and hydrogen storage mechanism of the above structures were analyzed, and the key indicators that may affect the hydrogen storage performance of MOFs were summarized: type and quantity of coordination metals, temperature, pressure, adsorption site and specific surface area.

Exploring the structural, elastic, phonon, optoelectronics, and thermoelectric properties of tetragonal complex metal hydride X2MgH4 (X=K, Rb, and Cs) compounds for hydrogen storage applications

Hydrogen storage is of great interest to researchers due to its renewable and clean energy properties. Therefore, there is a continuous search for innovative compounds that can provide hydrogen storage conditions. A first-principles study of X2MgH4 (X = K, Rb, and Cs) compounds has been carried out to investigate their physical properties using the Generalized Gradient Approximation (GGA) with the SIESTA package. The elastic, optical, structural, electronic, phonon, and thermoelectric properties of X2MgH4 (X = K, Rb, and Cs) compounds with tetragonal crystal structures have been investigated. The electronic properties of X2MgH4 (X = K, Rb, and Cs) compounds are insulators. All three compounds fulfil the Born stability condition. The gravimetric hydrogen storage capacities of X2MgH4 (X = K, Rb, and Cs) compounds are 3.8, 2.02, and 1.37 wt%, respectively. X2MgH4 (X = K, Rb, and Cs) crystals are dynamically stable. The thermoelectric and optical properties of X2MgH4 (X = K, Rb, and Cs) compounds are also discussed.

Effect of high-pressure torsion on first hydrogenation of Laves phase Ti0.5Zr0.5(Mn1-xFex)Cr1 (x = 0, 0.2 and 0.4) high entropy alloys

Laves phase high-entropy alloys are considered as good candidates for hydrogen storage applications. However, they usually suffer from poor first hydrogenation kinetics, the so-called activation process. In this paper, we attempt to solve the activation problem of the Ti0.5Zr0.5(Mn1-xFex)Cr1 (x = 0, 0.2 and 0.4) by high-pressure torsion (HPT). The HPT process was carried out under 6 GPa pressure for 5 revolutions in air on samples synthesized by arc melting. The hydrogenation kinetics were measured using a Sievert’s type apparatus at room temperature under 2 MPa of hydrogen pressure. While the as-cast alloys become totally inert to hydrogen after air exposure, the HPT-processed samples absorb 1.6–1.8 wt% of hydrogen at room temperature in a few seconds even after air exposure for 2 months. The easy activation of alloys processed by HPT is due to the formation of lattice defects that act as nucleation points. These results confirm that HPT processing is an effective strategy to develop active hydrogen storage materials.

A DFT investigation: High-capacity hydrogen storage in metal-decorated doped germanene

Germanene is a two-dimensional nanomaterial that has been successfully synthesized and has promising applications in sensing and energy storage. Recent research has focused on exploring the potential of M-decorated (M = K, Ca, and Sc) X-doped (X = B, Al, and Ga) germanene for hydrogen storage. In this theoretical work, a strong binding between K, Ca, and Sc metal atoms and doped germanene is revealed, suggesting that metal atoms adsorbed on doped germanene are energetically stable. Among the systems studied, Sc-decorated boron-doped germanene has a gravimetric hydrogen storage capacity of 5.32 wt%, close to the technical targets of the Department of Energy of the United States. Moreover, a three-atom Sc cluster on boron-doped germanene can adsorb up to 11 hydrogen molecules, with an average adsorption energy of 0.35 eV, desorption temperatures between 285 and 363 K and pressures between 5 and 100 bar. The desorption times are of the order of microseconds under ambient temperature conditions. Sc-decorated Al(Ga)-doped germanene systems could also be suitable for hydrogen storage at slightly increased temperatures or pressures, but K- and Ca-decorated monolayers are not. In summary, these findings demonstrate that Sc-decorated B-doped germanene can be a substrate for practical applications in hydrogen storage.

Magnetocaloric and hydrogen storage multi-functional properties of Eu4Ga8Ge16 compounds

We investigated the anisotropic magnetic, electrical transport, and heat capacity of Eu4Ga8Ge16 single crystals. Magnetization measurements with temperature and magnetic field revealed a complex behavior. Specifically, we observed anisotropic metamagnetic transitions at low magnetic field, and inverse hysteresis at high magnetic fields. These phenomena can be attributed to a Heisenberg ferromagnetic spin chain aligned along the a-axis. Additionally, this ferromagnetic behavior is interspersed with antiferromagnetic interactions between adjacent Heisenberg spin chains. We also noticed an anomalous increase in electrical resistivity at low temperature under magnetic fields, as well as different temperature-exponents of ρ(T) depending on crystal directions, which are attributed to the anisotropic scattering of carriers due to anisotropic magnetic interactions. We also evaluated the magnetocaloric effect and found a substantial magnetic entropy change than those of type-I Eu-based clathrates. The high entropy change (-ΔSM = 13.5 J kg−1 K−1) and adiabatic temperature difference (ΔTad = 7.8 K) near Néel temperature TN = 7.9 K reveal that the Heisenberg spin chain system might be advantageous for inducing a larger magnetic entropy change. Furthermore, we measured the hydrogen storage capacity of Eu4Ga8Ge16 as a multifunctional property because the zeolite-like cage structure can be a good candidate for hydrogen storage applications. Although the hydrogen storage capacity is considerably lower than that of the leading-edge materials, the hydrogen storage capacity can be improved further when we control the Eu-deficiency to place the hydrogen molecule at the cage site, because the hydrogen molecules reside at the (Ga,Ge) framework not in the cage site for fully occupied Eu atomic chain compounds. Hence, Eu4Ga8Ge16 emerges as a versatile substrate for engineering multifunctional energy materials, excelling in both low-temperature magnetocaloric effects and hydrogen storage potential.

Computational study on alkali and alkaline earth metal decorated B20 cluster for hydrogen storage application

Computational study on alkali and alkaline earth metal decorated B20 cluster for hydrogen storage application

2D N-doped layered mesoporous carbon sheets for high-performance electrochemical hydrogen storage

The rapid growth in energy demands and environmental concerns have drawn great attention to the development of new functional materials for sustainable energy technologies. As an emerging material, mesoporous carbon-based materials exhibit unique properties and have been considered promising candidates for electrochemical hydrogen storage applications. However, pure mesoporous carbon as electrode material may suffer from sluggish electrolyte transportation kinetic and poor hydrophilicity. Two-dimensional layered structure with high exposure area and nitrogen doping, which provides the improved accessibility of ions as well as the hydrophilicity of carbon materials, can cope with these two challenges. Here, the nitrogen-doped layered mesoporous carbon sheets, prepared by the double-hard-template route, were characterized using various technologies and investigated the electrochemically stored hydrogen energy properties. The results exhibit that hydrogen storage can be achieved around 104 mAh g−1 at 100 mA g−1, and the capacity retention was 85.4% at 2 A g−1. Moreover, it also displays superior cycling stability with a retention of 98% upon 300 cycles. According to the obtained results, the layered mesoporous carbon sheets demonstrated suitable capacity as a potential and promising active material for hydrogen-proton-related devices.

Machine learning-based high-throughput screening of Mg-containing alloys for hydrogen storage and energy conversion applications

The development of novel materials for hydrogen storage and conversion applications is expected to facilitate the transition to clean energy. In particular, near-ambient hydrogen storage, thermal energy storage, and lithium conversion electrodes are selected in this study as the applications for which the development of novel Mg-containing materials is of great importance. We utilize a machine learning model, based on the graph neural network, developed for predicting hydride formation enthalpy in intermetallic compounds, to perform high-throughput screening based on the atomic composition and crystal structure of the starting intermetallic compounds. Trends and structure-property relations are discussed, as well as the possibilities for tailoring the stability of Mg-containing hydrides by alloying. For 636 compounds identified as stable by DFT calculations, we predict hydride formation enthalpy and equilibrium potential of metal hydride conversion electrode for Li-ion batteries. Based on the predicted enthalpy of hydride formation, 32 intermetallics are identified as suitable for near-ambient hydrogen storage applications. Among them, MgBe13, seen as a promising material to achieve a high gravimetric density of hydrogen, is additionally studied using DFT. Further investigation of the Na-Mg-Al alloys is proposed as a good route in the search for new thermal energy storage materials. Binary Mg-containing intermetallics are discussed as conversion-type negative electrodes in Li-ion batteries.

Optimizing reactor structure to increase MgH2 dispersion and improve hydrolysis performance

Hydrogen has attracted wide attention due to its high calorific value, good combustion performance, non-toxic, and green characteristics. MgH2 has obvious advantages in hydrogen storage due to its high hydrogen storage density, mild hydrolysis conditions, rich raw materials, etc. However, poor hydrolysis kinetics limits its application in hydrogen storage. Different from research on MgH2 material modification, the physical method was employed to increase the MgH2 dispersion and improve the hydrolysis kinetics. Furthermore, hydrolysis reactors, including tubular, flaky and finned units, were designed and optimized. The results indicate that enhancing the dispersion of magnesium hydride can significantly improve the hydrolysis kinetics. The use of hydrolysis reactors with highly dispersed MgH2 can effectively enhance the controllability and continuity during the hydrolysis process. This can be attributed to the reduction in the surface coating of unreacted magnesium hydride by the generated magnesium hydroxide, as well as the improved transfer performance between the fresh hydrolysis solution and solid magnesium hydride. The findings of this study can further expand the range of reactor types for magnesium hydride hydrolysis and provide new insights for designing controllable and continuous hydrolysis reactors.

Hydrogen storage properties of surface oxidized LiBH4 system catalyzed with NiO nanorods and nanoplates

This paper highlights the hydrogen storage performance of surface oxidized LiBH4 (Lithium borohydride) system incorporated with NiO nanostructures under 250 °C. Surface oxidized LiBH4 system was impregnated with hydrothermally synthesized mesoporous NiO nanorods (NiONR) and NiO nanoplates (NiONP) using simple ultrasonication method. Hydrogen sorption and desorption studies has been investigated for LiBH4/NiONR and LiBH4/NiONP systems for the first time. The Brunauer-Emmett-Teller results showed that the specific surface area of NiONR, NiONP, LiBH4/NiONR and LiBH4/NiONP systems were 77.92, 88.12, 96.67 and 101.65 m2/g, respectively. Hydrogenation followed by isothermal dehydrogenation at 250 °C revealed that the LiBH4/NiONR and LiBH4/NiONP systems released ∼3.44 wt% and 4.02 wt% of hydrogen respectively in 60 min. Using the Kissinger's relation, the activation energy (Ea) was calculated as 69.28 and 63.23 kJ/mol for LiBH4/NiONR and LiBH4/NiONP systems, respectively. The dehydrogenation rate of LiBH4/NiONP system was found to be greater than that of LiBH4/NiONR system due to its large surface area and lower activation energy. The reported results revealed that nickel oxide nanostructures incorporated surface oxidized LiBH4 systems provide new opportunities for the solid-state hydrogen storage applications.

A Computational Model to Optimize the Electrochemical Reduction of CO2 to Formic Acid Using an Enzymatic Catalyst

This work documents the development and subsequent analysis of a transient electrochemical model to predict the electrochemical conversion of CO2 to formic acid (FA) using an enzymatic catalyst. FA has been of recent interest for its applications in hydrogen storage and formic acid-based fuel cells [1]. This process uses an electrochemical charge mediator, commonly methyl viologen (MV) or ethyl viologen (EV) [2], which is initially reduced to a more negative species (i.e. from EV2+ to EV+), then re-oxidized upon reacting with the enzymatic catalyst to produce FA (as HCOO-) from CO2 and protons from the anode.Using an enzymatic catalyst can enable greater selectivity to a particular carbon product compared to traditional metal-based catalysts, which can produce an array of different products [3]. The model was developed in conjunction with experimental investigation to serve as a benchmark for the optimal product conversion of CO2 assuming a stable solution pH and catalyst stability. The model employs transport-based equations for each ionic species of the charge carrier, which will vary based on the initial concentration selected and the applied voltage. Kinetic parameters to determine reaction values are fit to align with existing experimental data.The model uses Butler-Volmer kinetics to estimate the total current in the system as a function of the applied voltage and as a function of estimated experimental parameters. A bulk solution is considered for the electrolytes, but species concentrations are varied across a small diffusion layer (~50 um) between the electrolyte and electrode [4]. For predicting the conversion of CO2 into FA using the enzymatic catalyst and charge carrier species, Michaelis-Menten kinetics are used with appropriate catalyst parameters derived using sampling reactions with a known potassium formate solution and UV-vis spectroscopy.Among the products formed, molecular O2 is factored into the model as it will adversely limit the maximum current in the cell at higher applied voltage, and subsequently will limit the rate of production and efficiency. An O2 scavenger, such as sodium thiosulfate, can limit the contribution of molecular oxygen in the solution, but will not eliminate it. The model assumes that pH remains constant due to the presence of electrolyte buffer in the solution, although the influx of protons will cause a drop in the pH if not immediately converted to FA, and this more acidic solution has been shown to be a significant limitation due to the performance and stability of the catalyst.The results can be analyzed as a function of multiple parameters and operating conditions, although among the most interesting to study are those for the applied voltage and initial charge carrier concentration. There, it can be shown on contour plots that optimal regions for efficiency exist around -0.8 to -1.1 V (vs. Ag/AgCl), and charge carrier concentrations of 0.1 – 10 mM. The trends obtained are in alignment with what has previously been hypothesized [2] but can now also be analyzed in conjunction with other experimental parameters, including the design (sizing) of the electrochemical cell.The primary benefits of the model are in (1) predicting optimal performance when experimental imperfections are removed, (2) rapidly predicting a range of product selectivity and efficiency due to limited resources used to run experiments, primarily for the catalyst, and (3) providing a templating a template with which to iterate upon and consider other value added products, by altering parameters to account for a different catalyst, electrolyte, or charge mediator. The model is presently being developed to include provisions for operating in a flow cell reactor, where considerations to flow rate must be considered and time delay between reduction and production cells. To best match with existing experimental data, additional effects such as pH deterioration and variations in the kinetics with voltage (which can be investigated by cyclic voltammetry experiments) will need to be considered. REFERENCES: Singh AK, Singh S, Kumar A. Hydrogen energy future with formic acid: a renewable chemical hydrogen storage system. Catalysis Science & Technology. 2016;6(1):12-40.Moreno D, Thompson J, Omosebi A, Landon J, Liu K. Electrochemical analysis of charge mediator product composition through transient model and experimental validation. Journal of Applied Electrochemistry. 2022 Nov;52(11):1573-84.Ikeyama S, Amao Y. An Artificial Co‐enzyme Based on the Viologen Skeleton for Highly Efficient CO2 Reduction to Formic Acid with Formate Dehydrogenase. ChemCatChem. 2017 Mar 8;9(5):833-8.Morrison AR, van Beusekom V, Ramdin M, van den Broeke LJ, Vlugt TJ, de Jong W. Modeling the electrochemical conversion of carbon dioxide to formic acid or formate at elevated pressures. Journal of The Electrochemical Society. 2019 Feb 12;166(4):E77. Figure 1

A first-principles study to investigate the physical properties of Sn-based hydride perovskites XSnH3 (X = K, Li) for hydrogen storage application

Based on density functional theory, the present study used the Cambridge serial total energy package code to figure out the structural, electronic, magnetic, optical, and mechanical properties of perovskite hydrides XSnH3 (X = K, Li). The band gap, total density of states, and partial density of states of the hydrides under consideration have been calculated, confirming the metallic behavior via the overlapping of the conduction and valence bands with a zero-band gap. The XSnH3 lattice parameters, determined using generalized gradient approximations, are 4.3 Å for KSnH3 and 4.1 Å for LiSnH3. Both of these materials are found to be hard, antiferromagnetic, and anisotropic in nature. The Poisson's ratio indicates that LiSnH3 is brittle while KSnH3 is ductile. The B/G ratio also confirms the brittleness of LiSnH3 and the ductility of KSnH3. The hydrogen storage capacity of KSnH3 and LiSnH3 is calculated to be 1.88 wt % and 2.35 wt %. Both materials have the potential to store hydrogen, as evidenced by the storage properties, but it is determined that LiSnH3 is the superior material to utilize for use in applications involving hydrogen storage.

Improved hydrogen storage properties of MgH2 by Mxene (Ti3C2) supported MnO2

MgH2 is a promising high-capacity solid hydrogen storage material. In this work, MnO2-doped Ti3C2 (Ti3C2@MnO2) was synthesized and used as a catalyst to improve the hydrogen storage performance of MgH2. We found that the dehydrogenated 10 wt% Ti3C2@MnO2-doped MgH2 sample exhibited good hydrogen adsorption ability even at room temperature (30 °C), and could absorb 5.13 wt% of hydrogen in 400 s at 75 °C. The re‑hydrogenated Ti3C2@MnO2-doped MgH2 sample started to release hydrogen at 182 °C and required 484 s to completely release hydrogen at 275 °C with a dehydrogenation capacity of 6.4 wt%. The Ti3C2@MnO2 composite did not change the thermodynamic properties of MgH2. In the MgH2 + Ti3C2@MnO2 sample, Ti3C2, TiO2, MnO2, MnO, and Mn combined with MgH2 to form Ti3C2/MgH2, TiO2/MgH2, MnO2/MgH2, MnO/MgH2, and Mn/MgH2 multiphase interfaces, which improved the hydrogen storage performance of MgH2. The findings of this work may provide a new strategy for preparing novel and efficient catalysts for hydrogen storage applications.

Efficient hydrogen storage in LiMgF3: A first principle study

The utilization of hydrogen energy as a sustainable and renewable energy carrier has sparked considerable interest, but effective storage remains a challenge. To address this, researchers have turned their attention to hydride materials, which offer safe and efficient hydrogen storage capacity. In this study, we employed density functional theory calculations to investigate the structural and optoelectronic properties of LiMgF3-xHx (x = 0, 1, 2, and 3) hydrides, aiming to gain insights into their potential role in hydrogen storage. The optimized lattice parameter decreases from 3.95 to 3.86 Å with the inclusion of hydrogen. Further, we analyzed the density of states and band structure of each LiMgF3-xHx (x = 0, 1, 2, and 3) perovskite hydride, which depicts the decreasing trend in the bandgap due to increasing concentration of H. The Burstein-Moss shift and bandgap renormalization effects have been determined to assess the shifting of the absorption edge, which results in the narrowing of the bandgap. Furthermore, optical parameters were examined within the range of 0–10 eV, demonstrating a significant redshift in the absorption spectra in the UV region. The alteration in the optical properties and bandgap reduction are discussed in detail. Among the various hydrogen insertions, LiMgH3 displayed the highest static refractive index [n (0) = 2.01] and dielectric function, exhibiting minimal losses in absorption. These results emphasize that LiMgH3 is a promising candidate for hydrogen storage applications. Interestingly, the gravimetric and volumetric hydrogen storage capacities improved significantly from 1.4 to 8.8 wt% and 26.93–86.59 g.H2/l, respectively, which is a consequence of the increasing concentration of hydrogen in the host compound. This work might provide a significant contribution to both present and future research on practical hydrogen storage applications.