Solid Hydrogen Storage Research Articles

The role of hydrogen in the synthesis of High-entropy alloys and their hydrides

The aim of this work is to present the new technique processes of formation of stable hydrides of High-entropy alloys (HEAs) with high hydrogen content. The essence of the proposed method is the sequential use of self-propagating high-temperature synthesis (SHS) method for producing the metal hydrides, followed by the formation of alloys in the hydride cycle (HC) method. Preliminary, the hydrides of three compositions of metal mixtures were synthesized in SHS: 0.2TiH2+0.2ZrH2+0.2HfH2+0.2VH2+0.2NbH2, 0.3TiH2+0.15ZrH2+0.15HfH2+0.2VH2+0.2NbH2 and 0.3TiH2+0.1ZrH2+0.1HfH2+0.2VH2+0.2NbH2+0.1MgH2. From the synthesized mixtures of metal hydrides, the HEAs were produced in HC. The resultant hard alloys Ti0.2Zr0.2Hf0.2V0.2Nb0.2, Ti0.3Zr0.15Hf0.15V0.2Nb0.2 and Ti0.3Zr0.15Hf0.15V0.2Nb0.2Mg0.1 without crushing combusted in Н2 at РH2 = 5-30atm. in SHS mode. As a result, the hydrides of HEAs (Ti0.2Zr0.2Hf0.2V0.2Nb0.2)Н2.05, (Ti0.3Zr0.15Hf0.15V0.2Nb0.2)H2.05 and (Ti0.3Zr0.1Hf0.1V0.2Nb0.2 Mg0.1)H182 were synthesized with H2 content between 2.17-2.42wt.% and H/Me = 1.82-2.05. The repeating the hydrogenation-dehydrogenation processes for 1-3 times confirmed the exceptional cyclic stability of hydrides and the reversible high hydrogen storage capacity of the alloys. The regularities and the mechanism of formation of HEAs and their hydrides were elucidated. The applicability of combination of SHS and HC methods for synthesis of solid solutions of BCC structure HEAs and of their hydrogen-rich hydrides was demonstrated. The remarkable advantages of the developed efficient, low-energy consuming, waste-free and safe method for the synthesis of HEAs and their hydrides can be of commercial interest and attractive to industry, given the current needs for the development of renewable energy, in particular, the solid hydrogen storage facilities.

Characteristics of constant pressure dehydrogenation and construction of linear diffusion model for solid hydrogen storage materials: A case study of TiMn1.5 alloy

Solid-state hydrogen storage is considered to be the most promising hydrogen storage technology because of its high volumetric capacity and good security. The process of hydrogenation and dehydrogenation of solid hydrogen storage materials can be characterized by a diffusion kinetic model, which can be used to guide the safe and efficient application of hydrogen storage materials. Currently, experimental study on the dehydrogenation characteristics under constant pressure outer boundary condition has not been carried out methodically, and a simple and reliable diffusion kinetic model under this condition should be established based on the experimental results. In this study, an experimental platform for hydrogen absorption and constant pressure dehydrogenation of solid hydrogen storage materials was independently established. The TiMn1.5 alloy and its interstitial hydrides were taken as the experimental research objects to conduct constant pressure dehydrogenation tests, and the dehydrogenation properties at different temperatures were systematically studied. The results show that the dehydrogenation rate decreases with the increase of testing time. The ultimate capacity of hydrogen release increases first and then decreases with the increasing temperature, reaching the maximum value at 30 °C. It is found that the diffusion coefficient increases linearly with time during constant pressure dehydrogenation process. On this basis, a linear diffusion kinetic model is established. The initial diffusion coefficient D0 calculated by the new model has a quadratic polynomial relationship with temperature, and the increase coefficient α of diffusion coefficient has a linear relationship with temperature. According to the mathematical expressions, the dehydrogenation process of TiMn1.5 alloy at different temperatures can be predicted. The research results can provide theoretical guidance for the safe, efficient and controllable application of hydrogen storage materials.

Parametric Analysis of a Novel Array-Type Hydrogen Storage Reactor with External Water-Cooled Jacket Heat Exchange

Hydrogen energy is a green and environmentally friendly energy source, as well as an excellent energy carrier. Hydrogen storage technology is a key factor in its commercial development. Solid hydrogen storage methods represented by using metal hydride (MH) materials have good application prospects, but there are still problems of higher heat transfer resistance and slower hydrogen absorption and release rate as the material is applied to reactors. This study innovatively proposed an array-type MH hydrogen storage reactor based on external water-cooled jacket heat exchange, aiming to improve the heat transfer efficiency and absorption reaction performance, and optimize the absorption kinetics encountered in practical applications of LaNi5 hydrogen storage material in reactors. A mathematical model was built to compare the hydrogen absorption processes of the novel array-type and traditional reactors. The results showed that, with the same water-cooled jacket, the hydrogen absorption rate of the array-type reactor can be accelerated by 2.78 times compared to the traditional reactor. Because of the existence of heat transfer enhancement limits, the increase in the number of array elements and the flow rate of heat transfer fluid (HTF) has a limited impact on the absorption rate improvement of the array-type reactor. To break the limits, the hydrogen absorption pressure, as a direct driving force, can be increased. In addition, the increased pressure also increases the heat transfer temperature difference, thereby further improving heat transfer and absorption rate. For instance, at 3 MPa, the hydrogen absorption time can be shortened to 147 s.

Performance optimization of hydrogen storage reactors based on PCM coupled with heat transfer fins or metal foams

Metal hydride is a type of solid hydrogen storage material that offers excellent hydrogen absorption and desorption reaction properties. However, there is a strong thermal effect during the reaction process when the materials are applied in reactors. Thus, effective thermal management techniques are crucial for promoting efficient reactions. Prior studies on the subject have shown that phase change materials can be coupled with metal hydride reactors to transfer the reaction heat. To further enhance the transfer of heat and reaction efficiency of the metal hydride reactors based on phase change materials, this study explored heat transfer enhancement methods on the phase change materials side, including adding heat transfer fins and discussing the fin parameters and composite foam metal. The findings of the study showed that in comparison to the reactor without fins, the absorption rate of adding 10 sets of fins can increase by 28%, and as the number of fins increased to 14, this value could increase to 39.4%. The use of Y-shaped fins did not substantially improve the reaction rate, mainly due to the sufficient number of straight fins, and the heat transfer area reaching the limit of the fin enhanced the process of heat transport. Thus, the improved method of using copper foam is further considered. Compared with the reactor with and without fins, the absorption rate of the copper foam coupled reactor is increased by 23.4% and 61.3%, respectively.

Solar Hydrogen Production and Storage in Solid Form: Prospects for Materials and Methods.

Climatic changes are reaching alarming levels globally, seriously impacting the environment. To address this environmental crisis and achieve carbon neutrality, transitioning to hydrogen energy is crucial. Hydrogen is a clean energy source that produces no carbon emissions, making it essential in the technological era for meeting energy needs while reducing environmental pollution. Abundant in nature as water and hydrocarbons, hydrogen must be converted into a usable form for practical applications. Various techniques are employed to generate hydrogen from water, with solar hydrogen production-using solar light to split water-standing out as a cost-effective and environmentally friendly approach. However, the widespread adoption of hydrogen energy is challenged by transportation and storage issues, as it requires compressed and liquefied gas storage tanks. Solid hydrogen storage offers a promising solution, providing an effective and low-cost method for storing and releasing hydrogen. Solar hydrogen generation by water splitting is more efficient than other methods, as it uses self-generated power. Similarly, solid storage of hydrogen is also attractive in many ways, including efficiency and cost-effectiveness. This can be achieved through chemical adsorption in materials such as hydrides and other forms. These methods seem to be costly initially, but once the materials and methods are established, they will become more attractive considering rising fuel prices, depletion of fossil fuel resources, and advancements in science and technology. Solid oxide fuel cells (SOFCs) are highly efficient for converting hydrogen into electrical energy, producing clean electricity with no emissions. If proper materials and methods are established for solar hydrogen generation and solid hydrogen storage under ambient conditions, solar light used for hydrogen generation and utilization via solid oxide fuel cells (SOFCs) will be an efficient, safe, and cost-effective technique. With the ongoing development in materials for solar hydrogen generation and solid storage techniques, this method is expected to soon become more feasible and cost-effective. This review comprehensively consolidates research on solar hydrogen generation and solid hydrogen storage, focusing on global standards such as 6.5 wt% gravimetric capacity at temperatures between -40 and 60 °C. It summarizes various materials used for efficient hydrogen generation through water splitting and solid storage, and discusses current challenges in hydrogen generation and storage. This includes material selection, and the structural and chemical modifications needed for optimal performance and potential applications.

Fabrication of V2O3-TiO2-rGO ternary heterojunction composite to enhance the hydrogen storage performance of MgH2

The application prospects of MgH2 as a potential solid hydrogen storage material are limited by its stable thermodynamic properties and slow hydrogenation/dehydrogenation kinetics. In this study, a ternary heterogeneous composite material V2O3-TiO2-rGO (V-T-rGO) was synthesized using the ultrasonic hydrothermal method and doped into MgH2 through ball milling to improve its hydrogen storage performance. The experimental results demonstrated that the MgH2 + V-T-rGO samples exhibit superior hydrogen storage properties compared with single-doped V2O3, TiO2, rGO or V-T materials. Specifically, it can uptake hydrogen at room temperature, and adsorbs 5.00 wt% H2 in just 4 min at 150 °C, and releases 5.87 wt% H2 within 6 min at 325 °C, demonstrating a faster reaction rate and successful hydrogen absorption. Additionally, the hydrogenation/dehydrogenation activation energies of MgH2 + V-T-rGO samples are measured at 27.1/72.3 kJ·mol−1, representing a reduction of 51.2/59.2 kJ·mol−1 compared to MgH2 alone. Mechanistic analysis revealed that the multiphase composite system produced synergistic catalytic effects, providing abundant active sites and hydrogen diffusion channels to enhance the hydrogen storage performance of MgH2. This study presents an innovative approach for constructing transition metal oxide heterostructured materials and holds significant reference value for applications in the field of hydrogen storage.

A parametric study on hydrogen storage in AB5 hydride alloys: Heat and mass transfer, thermodynamics, and design

The design of heat exchangers plays an important role in the performance of solid-state hydrogen storage devices. In this study, three different designs of hydrogen storage devices were investigated, incorporating phase change material (PCM), specifically, RT25HC into their walls in various shapes. A mathematical model, validated using previous experimental data, was employed to calculate heat and mass transfer and determine the reaction time period. The calculations were conducted using ANSYS Fluent, with a constant hydrogen supply pressure of 10 bars and a temperature of 295 K. The absorption properties of the storage reactor were investigated through various parameters such as liquid fraction, hydrogen concentration, and natural convection heat transfer coefficients. Results showed that the geometric structure and PCM distribution significantly impacted the performance of the hydrogen storage devices. Design 1, with a centralized PCM distribution, demonstrated moderate heat transfer rates and a longer reaction time. Design 2, featuring a more distributed PCM layout, improved heat transfer rates and reduced hydrogen kinetics time by 40%. Design 3, which optimized the geometric structure with advanced PCM shapes, achieved the highest heat transfer rates and improved hydrogen kinetics time by 50%. This design also enabled the storage of thermal energy at a high density, ranging from 10.2 J/g to approximately 190.5 J/g. The study provides critical information on the design of efficient solid hydrogen storage processes. The findings suggest significant potential for improved performance in industrial applications such as electric vehicles and domestic energy supply. The high efficiency of the large-scale reactor is due to its well-designed system, which effectively converts chemical energy into thermal energy. Optimizing the reactor geometry and PCM distribution is crucial for achieving superior hydrogen storage and retrieval performance.

Hydrogen Storage Properties of Metal-Modified Graphene Materials

The absence of adequate methods for hydrogen storage has prevented the implementation of hydrogen as a major source of energy. Graphene-based materials have been considered for use as solid hydrogen storage, because of graphene’s high specific surface area. However, these materials alone do not meet the hydrogen storage standard of 6.5 wt.% set by the United States Department of Energy (DOE). They can, however, be easily modified through either decoration or doping to alter their chemical properties and increase their hydrogen storage capacity. This review is a compilation of various published reports on this topic and summarizes results from theoretical and experimental studies that explore the hydrogen storage properties of metal-modified graphene materials. The efficacy of alkali, alkaline earth metal, and transition metal decoration is examined. In addition, metal doping to further increase storage capacity is considered. Methods for hydrogen storage capacity measurements are later explained and the properties of an effective hydrogen storage material are summarized.

Ternary Fe–Ni–B particles supported on Cu(OH)2–Cu foam: A highly efficient and stable catalyst for hydrolysis of ammonia borane

Ammonia borane (NH3BH3) as a solid chemical hydrogen storage material with a high hydrogen content can be hydrolyzed under mild conditions to release hydrogen. In this work, Fe–Ni–B/Cu(OH)2–Cu foam was synthesized by combining in situ growth and electroless plating. Compared with the binary Fe–B/Cu(OH)2–Cu foam and Ni–B/Cu(OH)2–Cu foam prepared by the same method, the ternary Fe–Ni–B/Cu(OH)2–Cu foam has superior catalytic performance. The Fe–Ni–B/Cu(OH)2–Cu foam catalyst was able to achieve a maximum hydrogen production rate of 5.6 ml min−1 cm−2 at 298 K with an activation energy as low as 46.3 kJ mol−1. And more importantly, its catalytic efficiency has hardly decayed after ten cycles. These excellent properties are due to its low activation energy and the large specific surface, multi–site Cu(OH)2–Cu–foam carrier.

Efficient hydrogen absorption and dehydrogenation of synergistically catalyzed Mg10Fe by MoS2 and Y2O3 via one-step synthesis and multistage regulation

To effectively deal with the long preparation period and low hydrogen absorption capacity issue of Mg-based hydrogen storage materials. One-step multistage control strategy and high-pressure hydrogenation have been employed to prepare Mg10Fe-M (M = MoS2 or Y2O3 or both) composites. The phase composition, microstructure, morphology, non-isothermal dehydrogenation thermodynamics and isothermal dehydrogenation kinetics at different milling time (2, 4, 8 h) were explored, and the catalytic hydrogen absorption and discharge mechanism of Mg10Fe–MoS2–Y2O3 was proposed. The addition of MoS2 nanoflowers and Y2O3 powder can synergistically regulate and improve the hydrogenation capacity and dehydrogenation temperature of Mg10Fe. The hydrogen absorption and dehydrogenation of Mg10Fe–MoS2–Y2O3 in short time milling for 2 h are 3.64 wt% and 3.27 wt% respectively. After extending the milling time to 8 h, the thermodynamic and kinetic behavior of Mg10Fe-M (M = MoS2 or Y2O3 or both) is greatly improved. Kinetically, the hydrogenation or dehydrogenation capacity increases significantly, Mg10Fe–MoS2 doesn't need activation, and the hydrogenation capacity reaches 5.42 wt% at 623 K, with a yield of about 85.9 % in 60 min. Thermodynamically, the initial dehydrogenation peak temperature drops to about 310 °C, and the apparent activation energy also decreases significantly, among which Mg10Fe–MoS2–Y2O3 was 91.87 kJ/mol. These are attributed to the fact that MoS2 nanoflowers provide many active sites for H2 adsorption and H atom dissociation. Synchro-efficient synthesis and regulation of Mg-rich composite hydrogen storage materials are expected to shorten the synthesis cycle, improve the hydrogen storage performance, and lay a material foundation for the design and development of solid hydrogen storage devices.

Optimization of V-Ti-Fe hydrogen storage alloy based on orthogonal experiments

Vanadium-based solid solution hydrogen storage alloys have attracted much attention because of their high hydrogen capacity, mild hydrogen absorption- desorption conditions, and high safety. However, the V-Ti-Fe alloys, developed at low cost, have a relatively low effective capacity and is unsuitable for practical production. In this work, (VxFe100-x)100-yTiy-z%Ce (x=0.83,0.85,0.87; y=16,18,20; z=1,2,3) alloys are designed by orthogonal method to investigate the effect of compositions on the microstructure and hydrogen storage properties. It is shown that the effective hydrogen capacity and desorption plateau pressure of the (VxFe100-x)100-yTiy-z%Ce alloy are related to multiple factors, such as lattice constants, tetrahedral interstitials of the BCC and BCT phases, electron concentration and Vickers hardness. The optimized alloy (V87Fe13)82Ti18-1 %Ce based on the orthogonal experiments shows a reversible hydrogen storage capacity of 2.17 wt% and a desorption plateau pressure of 0.373 MPa at 70°C. The reversible hydrogen capacity of (V87Fe13)82Ti18-1 %Ce is superior to most V-Ti-Fe alloys.

MXenes and MXene-Based Metal Hydrides for Solid-State Hydrogen Storage: A Review.

Hydrogen-driven energy is fascinating among the everlasting energy sources, particularly for stationary and onboard transportation applications. Efficient hydrogen storage presents a key challenge to accomplishing the sustainability goals of hydrogen economy. In this regard, solid-state hydrogen storage in nanomaterials, either physically or chemically adsorbed, has been considered a safe path to establishing sustainability goals. Though metal hydrides have been extensively explored, they fail to comply with the set targets for practical utilization. Recently, MXenes, both in bare form and hybrid state with metal hydrides, have proven their flair in ascertaining the hydrides' theoretical and experimental hydrogen storage capabilities far beyond the fancy materials and current state-of-the-art technologies. This review encompasses the significant accomplishments achieved by MXenes (primarily in 2019-2024) for enhancing the hydrogen storage performance of various metal hydride materials such as MgH2, AlH3, Mg(BH4)2, LiBH4, alanates, and composite hydrides. It also discusses the bottlenecks of metal hydrides for hydrogen storage, the potential use of MXenes hybrids, and their challenges, such as reversibility, H2 losses, slow kinetics, and thermodynamic barriers. Finally, it concludes with a detailed roadmap and recommendations for mechanistic-driven future studies propelling toward a breakthrough in solid material-driven hydrogen storage using cost-effective, efficient, and long-lasting solutions.

ZIF‐8 decorated FeMo nanoparticles: H2 Production from the catalytic hydrolysis of ammonia‐borane

AbstractAmmonia‐Borane (AB) is considered a promising solid hydrogen storage material due to its high hydrogen content (19.6 wt%) and its use for safe hydrogen transport. The most effective way to produce H2 from AB is to perform the hydrolysis reaction in the presence of a suitable catalyst. In this study, Fe0.2Mo0.8/ZIF‐8 nanocatalyst was synthesized in two steps: (i) synthesis by following the colloidal synthesis technique by thermal decomposition of Mo(CO)6 and Fe(acac)3 in the presence of OM and ODE at high temperatures, and (ii) the resulting colloidal Fe0.2Mo0.8 NPs were decorated into ZIF‐8. The as‐prepared Fe0.2Mo0.8/ZIF‐8 catalyst was identified using advanced characterization techniques such as ICP‐OES, P‐XRD, SEM, SEM–EDX, TEM, TEM‐EDX, XPS, and BET. The catalytic activities of the Fe0.2Mo0.8/ZIF‐8 catalyst in the hydrolysis of AB were investigated in different parameters (temperature, catalyst [Fe0.2Mo0.8] and substrate [H3NBH3] concentration, and recyclability). The results show that high crystallinity Fe0.2Mo0.8 NPs with a uniform 1.31 ± 0.13 nm distribution were formed on the ZIF‐8 surface. Fe0.2Mo0.8/ZIF‐8 catalyst provides a maximum H2 generation rate of 184.2 mLH2 (g catalyst)−1 (min)−1 at 343 K. This uniquely cost‐effective, active and durable Fe0.2Mo0.8/ZIF‐8 catalyst has strong potential for H2‐based fuel cell (PEM: Proton Exchange Membrane) applications where AB is a suitable H2 carrier.Highlights FeMo NPs were synthesized by a colloidal synthesis method and decorated into ZIF‐8. FeMo/ZIF‐8 catalyst is an active catalyst in the hydrolysis of AB. FeMo/ZIF‐8 catalyst showed an initial TOF value of 449.85 mol(H2)·molFe0.2Mo0.8−1·h−1 in the AB hydrolysis at 338 K.

Solid hydrogen storage with palladium-graphene composites: Synthesis, characterization, and mechanistic insights

Efficient and safe hydrogen storage is a pivotal challenge for the advancement of hydrogen energy technologies. To address this, the engineering of high-performance solid-state hydrogen storage materials through the loading of transition metals (TM) on carbon-based solids has gained considerable interest. However, the mechanics for TM such as Palladium that bolster hydrogen storage have not well addressed yet. This work presents hydrogen absorptions with metal Pd nanoparticles loaded on reduced graphene oxide (Pd-rGO), including material preparation, structural characterization, hydrogen storage performance, and quantum chemical mechanistic insights. A simple material synthesis strategy has been explored and Pd-rGO composites are successfully prepared with graphite powder as raw materials by an easy reduction-oxidation process. Then, Pd-rGO composites are characterized using X-ray diffraction, Fourier-transform infrared spectroscopy, Raman, transmission electron microscopy, and nitrogen adsorption-desorption isotherms methods to clarify the detailed structural characteristics of Pd-rGO with different loading amounts. It is found that Pd nanoparticles with an average particle size of 10 nm are uniformly dispersed on the surface of rGO. The materials have high defect severity and increased specific surface areas with Pd loading. The hydrogen adsorption capacity of Pd-rGO can be increased by 64 % compared with that without Pd loading due to the hydrogen spillover effect. In addition, the intensification mechanism of hydrogen storage of Pd-rGO composites is further understood by using density functional theory calculations and surface interaction analysis.

Analysis Of the Current Situation and Prospective Study of Hydrogen Preparation and Storage

The research, development, and practical application of renewable energies are becoming a major trend with environmental problems such as increasingly serious global warming and the depletion of oil resources. Hydrogen is an ideal alternative energy source due to its cleanness and high combustion ratio. It is recognized as the most likely replacement for the existing coal and oil systems as the future energy base of the global economy. But as things stand, the hydrogen reserve technology and hydrogen storage technology at the current stage all have certain advantages and disadvantages. Based on this background, the study summarizes the current state of the art of hydrogen energy production technologies such as direct hydrogen production from fossil fuel, hydrogen production from electrolysis of water, hydrogen production from biomass, as well as four types of hydrogen storage methods, namely, high-pressure gaseous hydrogen storage, low-temperature liquid hydrogen storage, solid hydrogen storage, and organic liquid hydrogen storage, and analyzes the advantages and disadvantages of each technology. Among them, hydrogen production from electrolyzed water and bio-hydrogen production are the technologies with higher potential but still need to improve economic competitiveness. The high-pressure gaseous hydrogen storage technology can also be brought to market on a wide scale after cost reduction.

A novel carbon-induced-porosity mechanism for improved cycling stability of magnesium hydride

MgH2 has been extensively studied as one of the most ideal solid hydrogen storage materials. Nevertheless, rapid capacity decay and sluggish hydrogen storage kinetics hamper its practical application. Herein, a Ni/C nano-catalyst doped MgH2 (MgH2Ni/C) shows an improved hydrogen absorption kinetics with largely reduced activation energy. Particularly, the MgH2Ni/C displays remarkable cycling stability, which maintains a high capacity of 6.01 wt% (98.8 % of initial capacity) even after 50 full hydrogen ab/desorption cycles, while the undoped MgH2 counterpart retains only 85.2 % of its initial capacity. Detailed microstructure characterizations clearly reveal that particle sintering/growth accounts primarily for the deterioration of cycling performance of undoped MgH2. By comparison, MgH2Ni/C can maintain a stable particle size with a growing porous structure during long-term cycling, which effectively increases the specific surface of the particles. A novel carbon-induced-porosity stabilization mechanism is proposed, which can stabilize the proportion of rapid hydrogen absorption process, thus dominating the excellent cycling performance of MgH2Ni/C. This study provides new insights into the cycling stability mechanism of carbon-containing Mg-based hydrogen storage materials, thus promoting their practical applications.

Dipole-induced hydrogen bonds enhanced P/O co-doped Lyocell-based porous carbon fiber cloth for hydrogen storage under ambient pressure

Currently, the hydrogen storage application of carbon-based adsorbent materials is mostly implemented under the pressure conditions of 30–300 bar, while there is few targeted studies conducted on the unsaturated adsorption under ambient pressure conditions. Therefore, based on industrialized Lyocell biopolymer fiber precursors and the enhancement effects of dipole-induced hydrogen bonds (DIHB), this work presents a facile construction strategy for P/O co-doped Lyocell-based porous carbon fiber cloth (Ly-ACF-F40). By the technical route of thermal stabilization---sonication assisted phosphoric acid activation---hydrogen bonds introduced by interfacial fluorination, the constructed Ly-ACF-F40 acquires a high specific surface area (1870 m2/g) and total pore volume (1.277 cm3/g), and an excellent hydrogen storage capacity of 3.22 wt% under ambient pressure conditions (77 K, 1 bar). The study directly demonstrated in the experiment that dipole induced hydrogen bonding H(I)-H(II)···F can effectively enhance the atmospheric hydrogen storage density on the basis of other eliminating influencing factors of specific surface area. The simple construction strategy of porous carbon-based materials can provide reference for the research of unsaturated adsorption hydrogen storage materials under ambient pressure conditions, also assist in the application and promotion of low-cost solid hydrogen storage materials.

The relationship between thermal management methods and hydrogen storage performance of the metal hydride tank

Solid-state hydrogen storage tanks are key equipment for fuel cell vehicles and hydrogen storage. However, the low heat transfer properties of hydrogen storage tanks result in the inability to meet the hydrogen supply requirements of fuel cells. In this study, different thermal management approaches were explored through the design of LaNi5-based solid-state hydrogen storage tanks. We experimentally studied the effects of different internal heat transfer methods, that is, expanded natural graphite (ENG), copper foam, and copper fins on the hydrogen absorption and desorption performance. We also studied the effects of external cooling methods with natural convection, air cooling, and water cooling, respectively. Under the same external cooling method of natural convection, a solid hydrogen storage tank filled with 5 wt.% ENG has similar performance to a tank filled with copper foam. Compared to natural convection, air and water cooling can significantly improve the heating performance of metal hydride (MH) beds by increasing the external heat transfer coefficient. The effect of water cooling is better than that of air cooling, and in these two enhanced performance conditions, the tank filled with copper foam performs better than with ENG. In the case of water cooling, by adding copper fins to a hydrogen storage tank filled with 5 wt.% ENG, the tank was saturated with hydrogen absorption in only 29.4 min, which is 55.6 % shorter than the hydrogen uptake time in a hydrogen storage reactor without copper fins. And its stable hydrogen desorption (1 NL/min) has reached 98.1 % of the total hydrogen released. The results show that the effective thermal conductivity and heat transfer area of metal hydride bed play key roles in improving heat transfer and reaction rate. In addition, heat transfer is more important than mass transfer to improve the performance of the hydrogen storage tank.

Research Progress of Hydrogen Storage Materials

Hydrogen energy has become increasingly popular as a clean and renewable source of energy in recent years due to the high levels of carbon pollution worldwide. This essay examines the current research status on various hydrogen storage techniques and materials for hydrogen energy. There are currently three primary hydrogen storage methods: high-pressure gaseous hydrogen storage, low-temperature liquid hydrogen storage, and solid-state hydrogen storage. The most widely employed method in China is high-pressure gaseous hydrogen storage. It entails compressing hydrogen fuel into a container under high pressure. As a result, high-pressure gaseous hydrogen storage is commonly used for stationary hydrogen storage. Low temperature liquid hydrogen storage involves compressing the hydrogen at first and then cooling it down with liquefaction technology. However, due to the strict requirements for compression and container insulation, its actual performance is often limited. This paper focuses on the study of solid hydrogen storage materials. The physical adsorption materials that are successively introduced include carbon-based hydrogen storage materials, metal-organic frameworks (MOFs), and Covalent organic frameworks (COFs). In the current study, carbon-based hydrogen storage materials show better performance only in low-temperature and high-pressure environments, but MOFs and COFs have great prospects in hydrogen storage. The chemical absorption hydrogen storage materials introduced in this paper are metal alloy hydrogen storage and hydrogenation complexes hydrogen storage, mainly rare earth-based hydrogen storage materials and magnesium-based hydrogen storage materials. Among them, magnesium-based hydrogen storage materials have become one of the most promising hydrogen storage materials due to their low cost and good hydrogen storage performance.

Large-scale production of BCC solid solution hydrogen storage alloy

In this work, 52Ti–12V–36Cr + 4 wt% Zr alloy was synthesized at laboratory and large scales for comparative analysis of the hydrogen storage performance. A 5 g and 2 kg BCC solid solution alloy is synthesized by arc melting and induction melting, respectively. Crystal structure investigation revealed that both samples crystallized into a primary BCC phase and a secondary laves phase with no significant difference in the overall XRD pattern. First hydrogenation studies showed the maximum hydrogen storage capacity of arc melted alloy (AM) and induction melted alloys (IM) alloy are 3.5 wt% and 2.9 wt%, respectively, at room temperature under a hydrogen pressure of 20 bar. No visible incubation period was observed in AM alloy, whereas IM alloy showed an incubation period of 32 min with slower kinetics. The appearance of the incubation period and sluggish kinetics can be due to the formation of a passive layer during induction melting that changes the hydrogen sorption properties. The microstructural analysis confirmed the carbon contamination from the induction melting crucible and formation of the TiC phase in the matrix, which was absent in the AM alloy, significantly affecting hydrogen storage capacity. The enthalpy and entropy of 2 kg alloy are −65.84 kJ/mol and 188.92 J/mol-K.