Solid-state Hydrogen Storage Research Articles

Nano-enhanced solid-state hydrogen storage: Balancing discovery and pragmatism for future energy solutions

Nano-enhanced solid-state hydrogen storage: Balancing discovery and pragmatism for future energy solutions

Magnesium hydrogen storage: Temperature control via particle swarm with nonlinear inertia strategy

Magnesium-based hydrogen storage has garnered significant attention in the field of hydrogen storage due to its notable advantages, including high hydrogen storage capacity and low material cost. However, the relatively high thermodynamic stability of magnesium-based hydrogen storage materials necessitates heating the material to a specific temperature during the hydrogen charging and discharging processes, severely limiting the practical application and further development of this technology.Therefore, this paper aims to design a temperature control system for a magnesium-based solid-state hydrogen storage bottle. The system employs an optimized particle swarm optimization (PSO) algorithm to determine PID parameters, enabling rapid preheating of the hydrogen storage bottle and maintaining a stable operating temperature. Furthermore, by incorporating an appropriate penalty function, the system effectively suppresses temperature overshoot, preventing adverse effects on hydrogen storage performance caused by transient high temperatures, thereby ensuring the safety and stability of the hydrogen storage process.

Mxene-supported NbVH nanoparticles as efficient catalysts for reversible hydrogen storage in magnesium borohydride

Bimetallic niobium vanadium hydride nanoparticles (NbVH NPs) anchored on Ti3C2 were synthesized using a facile ball milling method as an effective catalyst for the dehydrogenation kinetics and reversibility of Mg(BH4)2. It was found that the onset dehydrogenation temperature of the Mg(BH4)2 + 30NbVH NPs@Ti3C2 composite was 105.7 °C and released 9.07 wt% of hydrogen at 330 °C, while undoped Mg(BH4)2 only released 4.2 wt% of H2 from 248 °C to 330 °C. Additionally, the Mg(BH4)2 + 30NbVH NPs@Ti3C2 composite achieved remarkable hydrogen release of over 9.44 wt% at a temperature as low as 230 °C, indicating unexpected dehydrogenation kinetics. In the reversible hydrogen desorption tests, Mg(BH4)2 + 30NbVH NPs@Ti3C2 released 5.98 wt% of H2 in the 2nd cycle at 250 °C and maintained a reversible capacity of 4.35 wt% after 10 cycles, demonstrating a remarkable enhancement in reversibility. The enhancement in the dehydrogenation kinetics of Mg(BH4)2 could be attributed to the greatly reduced activation energies from 343 kJ·mol−1 and 138.3 kJ·mol−1 to 103.7 kJ·mol−1 and 124 kJ·mol−1. Investigations on the evaluation of catalyst and Mg(BH4)2 during reversible hydrogen storage have revealed that NbVH NPs actually acted as a “bidirectional hydrogen pump”, facilitating both the hydrogen release and uptake from Mg(BH4)2. This strategy of multi-component hydrides may show a new way to design effective catalysts for solid-state hydrogen storage materials.

Effective thermal conductivity of LaNi5 powder beds for hydrogen storage: Measurement and theoretical analysis

Accurately measuring and analyzing the effective thermal conductivity of metal hydride beds is critical to design the structure of solid-state hydrogen storage tanks. On the basis of the steady-state radial heat flow method, a measurement cell of effective thermal conductivity was manufactured. The effective thermal conductivities of nonactivated and activated LaNi5 powder beds were measured in helium, nitrogen, and argon atmospheres with the temperature changing from 20 to 60 °C and pressure from 0.1 to 4.0 MPa. Then, the effective thermal conductivities were further analyzed using the Zehner–Schlünder–Damköhler model. Results show that the effective thermal conductivities can be enhanced by increasing gas thermal conductivity, gas pressure, and bed temperature. In addition, the effective thermal conductivities can be accurately predicted using the modified Zehner–Schlünder–Damköhler model considering the Smoluchowski effect (error < ± 5 %). With the use of the modified Zehner–Schlünder–Damköhler model, the contributions of different heat transfer pathways to the entire heat transfer of LaNi5 powder beds were analyzed. Approximately 70 %–91 % of the effective thermal conductivity of LaNi5 powder beds is contributed by the conduction of the particle–gas–particle pathway.

A density functional theory study of defective and doped structures of MgB2 and their interaction with hydrogen

The LiBH4+MgH2 system exhibits promising potential for solid-state hydrogen storage, yet the sluggish rehydrogenation of MgB2 poses a significant challenge. In this study, we utilize density functional theory (DFT) simulations to investigate the energetics of hydrogen in pure, defective, and doped MgB2 in equilibrium with molecular hydrogen. Our findings reveal that the B-Frenkel defect process is the thermodynamically most favorable in MgB2. The calculated solution energy for hydrogen at the interstitial site indicates low hydrogen solubility, even at mild temperatures. Incorporating hydrogen into a pre-existing B vacancy enhances the process, facilitated by doping of O on the B site. Additionally, Li doping on the Mg site enhances incorporation by forming strong Li–H bonds, predicting lower activation barriers for hydrogen dissociation and diffusion. Doping MgB2 with O and F at the B site significantly enhances hydrogen solubility. These dopants make MgB2 a promising material for high-capacity and fast-kinetics hydrogen storage applications, and further research into these effects can lead to advancements in energy storage technology.

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.

Advances and Prospects of Nanomaterials for Solid-State Hydrogen Storage.

Hydrogen energy, known for its high energy density, environmental friendliness, and renewability, stands out as a promising alternative to fossil fuels. However, its broader application is limited by the challenge of efficient and safe storage. In this context, solid-state hydrogen storage using nanomaterials has emerged as a viable solution to the drawbacks of traditional storage methods. This comprehensive review delves into the recent advancements in nanomaterials for solid-state hydrogen storage, elucidating the fundamental principles and mechanisms, highlighting significant material systems, and exploring the strategies of surface and interface engineering alongside catalytic enhancement. We also address the primary challenges and provide future perspectives on the development of nanomaterial-based hydrogen storage technologies. Key discussions include the role of nanomaterial size effects, surface modifications, nanocomposites, and nanocatalysts in optimizing storage performance.

Unraveling the kinetic mechanism of atomic hybrids for the catalytic dehydrogenation of MgH2

Herein, we report the multi-metal atomic catalysts for solid-state dehydrogenation of MgH2. It aims to reveal the multi-element synergy in catalysts for solid-state hydrogen storage. The kinetic measurements and fitting reveal two mechanisms: one shows a maximum rate at the early stage, such as V and Cr; the other needs a temperature-sensitive preparation time for its maximum rate, such as Ni. The combination of two catalyst components demonstrates the best kinetics: V and Cr boost the initial dehydrogenation, and Ni benefits the further hydrogen transfer which alleviates the rate of decay. This work provides guidelines for the design of multi-element doped catalysts for MgH2 dehydrogenation.

Mechanical processing and thermal stability of the equiatomic high entropy alloy TiVZrNbHf under vacuum and hydrogen pressure

This study investigates the potential of nanostructuring the equiatomic high entropy alloy TiVZrNbHf by high-pressure torsion to improve its already promising hydrogen absorption properties. The detailed microstructural analysis of the material after processing demonstrates that a homogenous single-phase nanocrystalline structure can be obtained despite shear band development. Due to the metastable character of many high entropy alloys, this analysis was complemented by investigating the thermal stability of the alloy under both vacuum and hydrogen pressure. For the latter, the material was characterized via in situ X-ray diffraction during hydrogen charging at 500 °C, giving a detailed insight into the phase evolution during initial absorption and subsequent cycling. These experiments evidenced the inherent metastability of TiVZrNbHf, which resulted in its decomposition into a bcc, hcp, and C14 Laves phase under both vacuum and hydrogen atmospheres. Despite decomposition, the material retained its nanocrystalline structure under hydrogen pressure, presumably due to hydride formation, while significant grain growth occurred under vacuum. These findings deepen the understanding of the deformation and hydrogen charging behavior of this promising high entropy alloy, suggesting an approach for engineering such alloys for enhanced stability and performance, particularly in solid-state hydrogen storage applications.

Picturing the Gap Between the Performance and US-DOE's Hydrogen Storage Target: A Data-Driven Model for MgH2 Dehydrogenation.

Developing solid-state hydrogen storage materials requires a comprehensive understanding of the dehydrogenation chemistry of a solid-state hydride. Transition state search and kinetics calculations are essential to understanding and designing high-performance solid-state hydrogen storage materials by filling in the knowledge gap that current experimentscannot measure. However, the ab initio analysis of these processes is expensive and time-consuming. Searching for descriptors to accurately predict the energy barrier is urgently needed, to accelerate the prediction of hydrogen storage material properties and identify the opportunities and challenges. Herein, we develop a data-driven model to describe and predict the dehydrogenation barriers of a typical solid-state hydrogen storage material, MgH2, based on the combination of the crystal Hamilton population orbital of Mg-H bond and the distance between atomic hydrogen.All the parameters in this model can be directly calculated with significantly less computational cost than conventional transition state search, so that the dehydrogenation performance of hydrogen storage materials can be predicted efficiently. Finally, we found that this model leads to excellent agreement with typical experimental measurements reported to date and provides clear design guidelines on how to propel the performance of MgH2 closer to the target set by the United States Department of Energy (US-DOE).

Exploring Nanomaterials for Hydrogen Storage: Advances, Challenges, and Perspectives.

Hydrogen energy heralded for its environmentally friendly, renewable, efficient, and cost-effective attributes, stands poised as the primary alternative to fossil fuels in the future. Despite its great potential, the low volumetric density presents a formidable challenge in hydrogen storage. Addressing this challenge necessitates exploring effective storage techniques for a sustainable hydrogen economy. Solid-state hydrogen storage in nanomaterials (physically or chemically) holds promise for achieving large-scale hydrogen storage applications. Such approaches offer benefits, including safety, compactness, lightness, reversibility, and efficient generation of pure hydrogen fuel under mild conditions. This article presents solid-state nanomaterials, specifically nanoporous carbons (activated carbon, carbon fibers), metal-organic frameworks, covalently connected frameworks, nanoporous organic polymers, and nanoscale metal hydrides. Furthermore, new developments in hydrogen fuel cell technology for stationary and mobile applications have been demonstrated. The review outlines significant advancements thus far, identifies key barriers to practical implementation, and presents a perspective for future sustainable energy research. It concludes with recommendations to enhance hydrogen storage performance for cost-effective and long-lasting utilization.

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.

Solubility of Hydrogen in a WMoTaNbV High-Entropy Alloy.

The WMoTaNbV alloy has shown promise for applications as a solid state hydrogen storage material. It absorbs significant quantities of H directly from the atmosphere, trapping it with high energy. In this work, the dynamics of the absorption of hydrogen isotopes are studied by determining the activation energy for the solubility and the solution enthalpy of H in the WMoTaNbV alloy. The activation energy was studied by heating samples in a H atmosphere at temperatures ranging from 20 °C to 400 °C and comparing the amounts of absorbed H. The solution activation energy EA of H was determined to be EA=0.22±0.02 eV (21.2 ± 1.9 kJ/mol). The performed density functional theory calculations revealed that the neighbouring host atoms strongly influenced the solution enthalpy, leading to a range of theoretical values from -0.40 eV to 0.29 eV (-38.6 kJ/mol to 28.0 kJ/mol).

Magnesium-Based Hydrogen Storage Alloys: Advances, Strategies, and Future Outlook for Clean Energy Applications.

Magnesium-based hydrogen storage alloys have attracted significant attention as promising materials for solid-state hydrogen storage due to their high hydrogen storage capacity, abundant reserves, low cost, and reversibility. However, the widespread application of these alloys is hindered by several challenges, including slow hydrogen absorption/desorption kinetics, high thermodynamic stability of magnesium hydride, and limited cycle life. This comprehensive review provides an in-depth overview of the recent advances in magnesium-based hydrogen storage alloys, covering their fundamental properties, synthesis methods, modification strategies, hydrogen storage performance, and potential applications. The review discusses the thermodynamic and kinetic properties of magnesium-based alloys, as well as the effects of alloying, nanostructuring, and surface modification on their hydrogen storage performance. The hydrogen absorption/desorption properties of different magnesium-based alloy systems are compared, and the influence of various modification strategies on these properties is examined. The review also explores the potential applications of magnesium-based hydrogen storage alloys, including mobile and stationary hydrogen storage, rechargeable batteries, and thermal energy storage. Finally, the current challenges and future research directions in this field are discussed, highlighting the need for fundamental understanding of hydrogen storage mechanisms, development of novel alloy compositions, optimization of modification strategies, integration of magnesium-based alloys into hydrogen storage systems, and collaboration between academia and industry.

Innovative Design of Solid-State Hydrogen Storage and Proton Exchange Membrane Fuel Cell Coupling System with Enhanced Cold Start Control Strategy

This paper presents an innovative thermally coupled system architecture with a parallel coolant-heated metal hydride tank (MHT) designed to satisfy the hydrogen supply requirements of proton exchange membrane fuel cell s(PEMFCs). This design solves a problem by revolutionising the cold start capability of PEMFCs at low temperatures. During the design process, LaNi5 was selected as the hydrogen storage material, with thermodynamic and kinetic properties matching the PEMFC operating conditions. Afterwards, the MHT and thermal management subsystem were customised to integrate with the 70 kW PEMFC system to ensure optimal performance. Given the limitations of conventional high-pressure gaseous hydrogen storage for cold starting, this paper provides insights into the challenges faced by the PEMFC-MH system and proposes an innovative cold start methodology that combines internal self-heating and externally assisted preheating techniques, aiming to optimise cold start time, energy consumption, and hydrogen utilisation. The results show that the PEMFC-MH system utilises the heat generated during hydrogen absorption by the MHT to preheat the PEMFC stack, and the cold start time is only 101 s, which is 59.3% shorter compared to that of the conventional method. Meanwhile, the cold start energy consumption is reduced by 62.4%, achieving a significant improvement in energy efficiency. In conclusion, this paper presents a PEMFC-MH system design that achieves significant progress in terms of time saving, energy consumption, and hydrogen utilisation.

Advancements in Solid-State Hydrogen Storage: A Review on the Glass Microspheres.

Glass microspheres, with their unique internal structure and chemical stability, offer a promising solution for the challenges of hydrogen storage and transmission, potentially advancing the utility of hydrogen as a safe and efficient energy source. In this review, we systematically evaluate various treatment and modification strategies, including fusion, sol-gel, and chemical vapor deposition (CVD), and compare the performance of different types of glass microspheres. Our synthesis of current research findings reveals that specific low-cost and environmentally friendly modification techniques can significantly enhance the hydrogen storage efficiency of glass microspheres, with some methods increasing storage capacity by up to 32% under certain conditions. Through a detailed life-cycle and cost-benefit assessment, our study highlights the economic and sustainability advantages of using modified glass microspheres. For example, selected alternative materials used in lightweight vehicles have been shown to reduce density by approximately 10% while reducing costs. This review not only underscores the contributions of modified glass microspheres to overcoming the limitations of current hydrogen storage technologies but also provides a systematic framework for improving their performance in hydrogen storage applications. Our research suggests that modified glass microspheres could help to make hydrogen energy more commercially viable and environmentally friendly.

Current Research Status on The Production, Storage, And Application of Hydrogen Energy

With the development of society, the demand for energy has significantly increased, and the hydrogen energy industry is an important engine for optimizing energy structure and promoting the transformation of traditional energy. Hydrogen energy is a clean and renewable energy source with abundant sources. The unit mass of hydrogen contains a large amount of energy and can be applied in a wide range of fields. Therefore, analyzing and comparing the hydrogen energy industry chain will contribute to the healthy development of the hydrogen energy industry. This article first investigates the initial stage of development, current situation, and policies of hydrogen energy in China, Japan, and the United States, in order to gain a deeper understanding of the research status and planning of hydrogen energy in different countries. Secondly, the current mature hydrogen production methods (reforming hydrogen, electrolysis hydrogen) and hydrogen storage methods (high-pressure hydrogen storage, solid-state material hydrogen storage, organic liquid hydrogen storage materials) Hydrogen application are analyzed, and their advantages are proposed. Finally, based on research analysis, the future hydrogen energy market is introduced. This research result also provides certain reference value for enterprises that need to transform and enter the hydrogen energy field.

Modeling hydrogen storage at room temperature: Adsorbent materials for boosting pressure reduction in compressed H2 tanks

Energy storage systems are required for an efficient integration of renewables into the grid to achieve a net zero energy system. Hydrogen compressed at 700 bar, is one of the key energy storage technologies. This study evaluates the effectiveness of solid-state hydrogen storage, particularly physisorption in porous materials, to enhance storage performance and safety at room temperature by reducing the operating tank pressure. We model dynamically the entire storage system, comparing adsorbent materials to traditional compression in terms of maximum tank pressure and round-trip storage efficiency. Different energy system applications with varied cycle frequencies and discharge durations were examined. Results indicate that porous material-based systems exhibit higher efficiency for long-duration energy storage services than the compressed hydrogen. Notably, bulk density plays a pivotal role in storage performance. For instance, IRMOF-1 with a bulk density of 500 kg/m3, shows a 70 % pressure reduction compared to compressed hydrogen systems. In contrast, when its bulk density is reduced to 130 kg/m3, the maximum tank pressure is even 30 % higher than the compressed tank. We emphasize the need for comprehensive material characterization, highlighting the significance of parameters like bulk density for determining the most performing hydrogen adsorbent material in terms of maximum tank pressure and efficiency. As general outcome, the best performing material depends on the specific target or system requirements, such as pressure, volume, cost, or weight.

Improved dehydrogenation performance of LiAlH4 doped with BaMnO3

Due to its high gravimetric capacity of hydrogen (10.5 wt%), LiAlH4 has been regarded as a promising material for solid-state hydrogen storage material for onboard usage. However, high decomposition temperature, poor kinetics and irreversibility retard its application. To counter this problem, various weight percentages of BaMnO3 are introduced into the LiAlH4 system as an additive in this work. As a result, the starting hydrogen release of LiAlH4 was reduced to 109−115 °C and the second desorption temperature occurred at around 134−158 °C, much lower than pure LiAlH4. The isothermal desorption kinetics also proved that faster desorption kinetics can be observed at 90 °C for 80 min. About 2.00−2.60 wt% of H2 could be desorbed by the composite, whereas only <1.00 wt% of H2 was desorbed by undoped LiAlH4. Additionally, adding BaMnO3 reduced the activation energies by 30 kJ/mol for the first stages and 34 kJ/mol for the second stages. Based on the X-ray diffraction result, the active species formed of MnO2 and Ba or Ba−containing materials are believed to be responsible for the noticeable enhancement in the desorption properties of LiAlH4.

Sorption properties of nanostructured ball-milled porous silicon for solid-state hydrogen storage up to 80 bar

Solid-state storage is a feasible solution to store hydrogen compared to commercially available techniques. The disadvantage of using metal and complex hydrides for storage is the elevated temperature operation (>400 °C) and slow reaction kinetics. Porous materials like carbon nanostructures, metal-organic frameworks, zeolites, and porous polymers possess high surface energy and hydrogen affinity. However, cryogenic temperature operation and low storage at ambient conditions are major limitations for practical storage applications. Modifying the material morphology and storage parameters to enhance hydrogen storage is under intense investigation. This study focuses on nanostructuring porous silicon (PS), evaluating its structural characteristics, and investigating its ability to store hydrogen at up to 80 bar. The challenges of large particle size and low-pressure hydrogen storage in the novel porous material is addressed with possible mechanisms. The discussion explored the potential of utilizing interconnected pores via nanoscale engineering and increased charging pressure to optimize hydrogen exposure. Nanostructuring the hand-grinded porous Si (HGPS) reduces crystallite size, boosts surface energy and enhances thermodynamics. At 80 bar and 120 °C, the ball-milled PS (BMPS) exhibits a hydrogen storage capacity of 10.7 wt%. The isosteric heat of adsorption is utilized to optimize storage conditions to achieve useable capacity. The hydrogen adsorption pressure is optimized between 40 and 60 bar, where the storage capacity ranges from 2 wt% and 6 wt% (meeting the hydrogen storage target set by the US Department of Energy). X-ray Photoelectron Spectroscopy investigates surface states and bonding involving silicon hydrides. The effect of nanostructuring on decomposition energy is observed by differential scanning calorimetry. The decreased crystallite size, examined through X-ray diffraction and Raman spectroscopy, exposes nanopores accessible to hydrogen. The accessibility enhances storage capacity in free and surface-affixed states, rendering BMPS for reversible storage applications. The lower temperature requirement for hydrogen adsorption and release from storage material aligns with Sustainable Development Goal 7 (SDG 7) on affordable and clean energy.