Pristine [formula omitted] monolayer as highly efficient reversible hydrogen storage material under ambient temperature and pressure

First principle studies on triphenylene-hexathiol-based metal-organic framework for hydrogen storage application

Hydrogen is a promising candidate for renewable energy storage and transportation due to its high energy density and zero carbon emissions. Its practical applications face challenges related to safe, efficient storage and release systems. This review article investigates advanced nanostructured materials for hydrogen storage, including metal acetylide and cyanide complexes, B,N-doped γ-graphyne nanotubes (γ-GNT), lithium-phosphide double helices, and Ni-decorated carbon-based clusters. Density Functional Theory (DFT) based computations are used to analyze binding energies, thermodynamic stability, and adsorption mechanisms. Ni-decorated C12N12 nanoclusters demonstrate enhanced storage capacities, binding up to eight H2 molecules with a favorable N-(μ-Ni)-N configuration. Lithium-phosphide double helices show potential for 9.6 wt% hydrogen storage within a stable, semiconducting framework. Functionalization of γ-GNT with OLi2 at boron-doped sites significantly enhances storage potential, achieving optimal hydrogen binding energies for practical applications. Additionally, metal acetylide and cyanide complexes, stabilized by noble gas insertion, display thermodynamically favorable hydrogen adsorption. These results highlight the potential of these functionalized nanostructures for achieving high-capacity, reversible hydrogen storage. The nanostructures in this study, such as γ-graphyne nanotubes (γ-GNT), lithium-phosphide double helices, metal acetylide and cyanide complexes, and Ni-decorated carbon-based clusters, are selected based on their ability to exhibit complementary hydrogen adsorption mechanisms, including physisorption and chemisorption. γ-GNT offers high surface area and tunable electronic properties, ideal for physisorption enhanced by heteroatom doping. Lithium-phosphide double helices facilitate Kubas-like chemisorption through unsaturated lithium centers. Metal acetylide and cyanide complexes stabilize hydrogen adsorption via charge transfer and conjugated frameworks, while Ni-decorated clusters combine polarization-induced physisorption. These materials represent a strategic approach to addressing the challenges of hydrogen storage through diverse and synergistic mechanisms. The review also addresses challenges and outlines future directions to advance hydrogen's role as a sustainable fuel.

Metal-decorated Tri-graphene as a high-performance reversible hydrogen storage medium: A first-principles study

High capacity and reversible hydrogen storage on two dimensional C2N monolayer membrane

Stabilized Li-decoration and enhanced hydrogen storage on reduced graphene oxides

A highly cross-linked polymeric complex (MTF-Fe) with exposed under-coordinated iron metals is synthesized through the reaction of Fe-modified-melamine with terephthaldehyde for room temperature hydrogen storage via physisorption. The MTF-Fe shows a hydrogen storage capacity of 1.7 wt% at 298K and 100 atm. As a service to our authors and readers, this journal provides supporting information supplied by the authors. Such materials are peer reviewed and may be re-organized for online delivery, but are not copy-edited or typeset. Technical support issues arising from supporting information (other than missing files) should be addressed to the authors. Please note: The publisher is not responsible for the content or functionality of any supporting information supplied by the authors. Any queries (other than missing content) should be directed to the corresponding author for the article.

Hydrogen storage on lithium decorated zeolite templated carbon, DFT study

Green fabrication of cost-effective and sustainable nanoporous carbons for efficient hydrogen storage and CO2/H2 separation

The shift from fossil fuels to renewable energy sourcesis essentialfor reducing global carbon emissions and addressing climate change.Developing advanced materials for efficient hydrogen storage enablesthe development of sustainable energy solutions in this context. Herein,we propose sodium-decorated TPHE-graphene as a high-performance two-dimensionalmaterial for hydrogen storage. Density functional theory calculationsand molecular dynamics simulations demonstrate that TPHE-grapheneexhibits dynamical, thermal, energetic, and mechanical stability.The monolayer displays metallic behavior and a high Young’smodulus of 250.46 N/m. Upon sodium decoration, strong chemisorptionoccurs with a binding energy of −2.08 eV and minimal tendencyfor Na atom clustering. Hydrogen adsorption analysis reveals thateach Na atom can bind up to five H2 molecules, resultingin a gravimetric storage capacity of 9.52 wt %. The calculated H2 adsorption energies range from −0.22 to −0.18eV, falling within the ideal range for reversible adsorption underambient conditions. These findings highlight Na-decorated TPHE-grapheneas a structurally robust and efficient hydrogen storage material well-suitedfor future green energy applications.

An evolving energy solution: Intermediate hydrogen storage

Employing density functional theory simulations, we have predicted Y-decorated Ψ-graphene as a potential hydrogen storage material for fuel cell vehicle (FCV) applications. The system is stable at ambient and higher temperatures as substantiated by ab initio molecular dynamics simulations and is capable of holding 8.31 wt. % of hydrogen, higher than the U.S. Department of Energy (DOE) target. Each Y atom attached on Ψ-graphene can adsorb seven H2 molecules with a mean binding energy of −0.39 eV per H2 and a desorption temperature of 496.55 K—highly suitable for fuel cell applications. The Y atom binds strongly with the Ψ-graphene sheet, evident from the binding energy of −3.06 eV. The presence of a diffusion energy barrier of 0.4–0.7 eV for the diffusion of Y atom across Ψ-graphene may prevent metal–metal clustering. The flow of charge is found to be from Y atom 4d orbitals toward the C 2p orbitals of Ψ-graphene. Hydrogen molecules are found to bind reversibly by Kubas interactions involving charge donation and back donation between Y atom 4d orbitals and 1s orbitals of hydrogen, allowing for a suitable binding energy for FCV applications. Considering the stability of the system, optimum binding energy, and desorption temperature as per U.S. DOE targets; adequate barrier energy for diffusion; and excellent gravimetric hydrogen storage capability of the material, we propose Y-decorated Ψ-graphene as a potent hydrogen storage material for FCV applications.

High-density storage of gases remains a major technological hurdle for many fields. The U.S. Department of Energy (DOE), for example, reduced their hydrogen storage targets for automotive applications due to the inability of technologies to reach the system-level targets.1 Without significant improvements in hydrogen storage density, hydrogen as a transportation fuel remains unfeasible. In other fields, the low volumetric and gravimetric storage densities of oxygen gas cylinders can be cumbersome or prohibitively expensive for applications like terrestrial and marine breathing apparatus’ or manned space exploration. Emerging technologies such as sorbents and chemical complexes show potential for gas storage. However, the ability to achieve application-specific gas delivery rates and high storage densities, while operating reversibly at ambient temperature, remains elusive.2, 3 In contrast, it may be possible to achieve high gas storage densities and potentially high gas delivery rates using nanocapillaries when used in conjunction with a membrane electrode assembly (MEA). Hoop stress calculations show that the pressure tolerances of cylinders are inversely proportional to the radius. Indeed, glass microcapillaries have already theoretically4 and experimentally5 demonstrated the capacity to achieve DOE hydrogen storage targets at a materials-level. This technology can be further improved by reducing the capillary radius to the nanoscale; however, the capping and pressurization of the gas in micro- or nanocapillaries remains problematic. Presented here is the fabrication of nanocapillary arrays capped by an MEA for highly reversible storage of gases with the potential for high rate pumping and high-density storage. Very high aspect ratio and densely packed nanocapillary arrays are produced through aluminum anodization. The nanocapillary arrays are capped with either a PEM or an alkaline (anion) exchange membrane (AEM) complete with catalyst nanoparticles on either side of the membrane to form an MEA. This MEA is used to provide controllable electrochemical pumping of hydrogen or oxygen gas into and out of the nanocapillaries. The MEA also serves as a high pressure seal. A theoretical discussion of the potential volumetric and gravimetric storage densities of hydrogen and oxygen in nanocapillary arrays will be presented together with experimental results of electrochemical gas compression into lab-scale devices. The evaluation of both commercial catalyst materials and fabricated nanoparticle catalysts (<10 nm) for hydrogen and oxygen pumping will be discussed. In addition, the performance of both PEM and AEM for electrochemical pumping of oxygen will be compared. A discussion of the electrochemistry within nanocapillaries compared to planar MEAs will be given including the charge transport/transfer processes. The potential failure mechanisms and the technical obstacles to the implementation of our electrochemical membrane approach, together with the current state of the technology and overall storage capacities, will be presented. 1. Hydrogen, Fuel Cells and Infrastructure Technologies Program: Multi-Year Research, Development and Demonstration Plan. US Department of Energy, Energy Efficiency and Renewable Energy 2012. 2. Zhou, L., Progress and problems in hydrogen storage methods. Renewable and Sustainable Energy Reviews 2005, 9 (4), 395-408. 3. Pukazhselvan, D.; Kumar, V.; Singh, S., High capacity hydrogen storage: basic aspects, new developments and milestones. Nano Energy 2012, 1 (4), 566-589. 4. Zhevago, N.; Glebov, V., Hydrogen storage in capillary arrays. Energy Conversion and Management 2007, 48 (5), 1554-1559. 5. Zhevago, N.; Denisov, E.; Glebov, V., Experimental investigation of hydrogen storage in capillary arrays. International Journal of Hydrogen Energy 2010, 35 (1), 169-175.

The lack of safe, efficient, and economical hydrogen storage technologies is a hindrance to the realization of the hydrogen economy. Reported herein is a reversible formate-based carbon-neutral hydrogen storage system that is established over a novel catalyst comprising palladium nanoparticles supported on nitrogen-doped mesoporous carbon. The support was fabricated by a hard template method and nitridated under a flow of ammonia. Detailed analyses demonstrate that this bicarbonate/formate redox equilibrium is promoted by the cooperative role of the doped nitrogen functionalities and the well-dispersed, electron-enriched palladium nanoparticles.

Ultrastrong and ductile additively manufactured precipitation-hardening medium-entropy alloy at ambient and cryogenic temperatures

Exploring yttrium doped C24 fullerene as a high-capacity reversible hydrogen storage material: DFT investigations