Hydrogen storage materials and methods of use thereof

Abstract

This invention relates to hydrogen storage materials, and to devices, systems and methods utilizing the hydrogen storage materials.

Description

HYDROGEN STORAGE MATERIALS AND METHODS OF USE THEREOF CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims the benefit of priority under 35 U.S.C. §119(e) to U.S. Provisional Patent Application No. 63 / 450,606 filed March 7, 2023, the contents of which is incorporated herein by reference in its entirety. STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT

[0002] This invention was made with government support under Grant No. N00014-23-1- 2034 awarded by the U.S. Department of the Navy, Office of Naval Research. The government has certain rights in the invention. FIELD OF INVENTION

[0003] This invention relates to hydrogen storage materials, and to devices, systems and methods utilizing the hydrogen storage materials. BACKGROUND

[0004] All publications herein are incorporated by reference to the same extent as if each individual publication or patent application was specifically and individually indicated to be incorporated by reference. The following description includes information that may be useful in understanding the present invention. It is not an admission that any of the information provided herein is prior art or relevant to the presently claimed invention, or that any publication specifically or implicitly referenced is prior art.

[0005] Global energy demand has seen a substantial increase in the past decade, from 408 EJ in 2000 to 585 EJ in 2019, fueled by the world’s population growth and advanced technologies. As fossil fuels are the main source to fulfill this demand, global concerns on climate change and air and water pollutions are mounting. Hydrogen (^ଶ) is one of the most suitable options among all the sustainable sources to address these concerns as it has one of the highest energy contents per unit mass (142 MJ / kg) compared with all other fuels, and the only product of ^ଶcombustion is water vapor, which makes it a zero-emission fuel. Projections indicate that ^ଶ^will provide 18% 4865-9272-1067.1 Page 1 of 49094876-000007WOPTof the total global energy demand by 2050. This transition, however, requires these prerequisites to be fulfilled: identifying suitable ^ଶproduction sources and optimizing ^ଶ^ production techniques and storage methods. Among these, ^ଶ^storage is a key enabling technology for the deployment of ^ଶ^in applications including stationary power, portable power, and transportation. Besides the high storage capacity, the storage systems must have both acceptable operating temperatures and pressures, fast charging and discharging rates, and minimal energy required for the discharging process.

[0006] In the future landscape of sustainable energies and in combating global climate challenges, hydrogen plays a crucial role in both stationary and portable energy systems that currently supply 18% of the total energy demand. High-capacity, safe, and cost-effective hydrogen storage is critical for advancing the hydrogen economy but remains a dauting challenge. A range of advanced material systems including metal hydrides, metal-organic frameworks, and 2D materials have been explored in efforts to achieve high storage capacity, but high operating pressures, low charging / discharging rates, and energy intensive discharging processes have hindered their development and deployment.

[0007] Despite these progresses in materials design, identifying materials with high storage capacities at low operating pressures accompanied by high charging and discharging rates without the prerequisite of high temperatures for discharging remains a challenge. As such, there is an ongoing need for improvements in materials, devices, methods, and systems for hydrogen storage. The embodiments of the present invention address that need. SUMMARY OF THE INVENTION

[0008] In various embodiments, the present invention provides a hydrogen storage material, the hydrogen storage material comprising: a mesoporous zeolite, wherein the mesoporous zeolite comprises a plurality of mesopores. In some embodiments, the mesoporous zeolite is a modified zeolite Y. In some embodiments, the plurality of mesopores have a pore size of 1.0 nm to 50.0 nm. In some embodiments, the pore size is 2.0 nm to 3.0 nm, or wherein the pore size is 2.4 nm. In some embodiments, the mesoporous zeolite comprises a surface area of 1100 m2g-1. In some embodiments, the mesoporous zeolite is a powder. In some embodiments, the mesoporous zeolite comprises at least one concave surface. In some embodiments, the mesoporous zeolite comprises an aluminosilicate framework, or the mesoporous zeolite comprises a FAU crystal4865-9272-1067.1Page 2 of 49094876-000007WOPTstructure. In some embodiments, the mesoporous zeolite comprises a hydrogen storage capacity of about 1.23 wt% to about 2.1 wt% based on the total weight of the mesoporous zeolite at a pressure of about 6 bar to about 10 bar. In some embodiments, the mesoporous zeolite has a hydrogen charging time of 0.16 hours at a pressure of 10 bar, or the mesoporous zeolite has a hydrogen discharging time of 1.42 hours at a temperature of 273 K.

[0009] In various embodiments, the present invention provides a hydrogen storage system, comprising: an inlet port; a reaction chamber, wherein the reaction chamber is in communication with the inlet port, and wherein the reaction chamber contains a hydrogen storage material of the present invention; and an outlet port, wherein the outlet port is in communication with the reaction chamber. In some embodiments, the reaction chamber further contains water, or at least one promoter, or both water and at least one promoter. In some embodiments, the at least one promoter is tetrahydrofuran (THF) or tetrahydrothiophene (THT).

[0010] In various embodiments, the present invention provides a method for storing hydrogen, the method comprising: providing a hydrogen storage material of the present invention; providing water, or at least one promoter, or both water and at least one promoter; contacting the hydrogen storage material with the water, the at least one promoter, or both; filling at least a portion of the plurality of mesopores of the hydrogen storage material with the water, the at least one promoter, or both to provide an activated hydrogen storage material; and contacting the activated hydrogen storage material with hydrogen gas under conditions suitable for storing hydrogen in at least a portion of the plurality of mesopores of the hydrogen storage material. In some embodiments, the hydrogen gas is stored in the form of at least one hydrogen hydrate in at least a portion of the plurality of mesopores of the hydrogen storage material. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Exemplary embodiments are illustrated in referenced figures. It is intended that the embodiments and figures disclosed herein are to be considered illustrative rather than restrictive.

[0012] FIG. 1A – FIG. 1D depicts in accordance with various embodiments of the invention, (FIG.1A) Schematic of a material platform for high-capacity hydrogen storage in which a powder of mesoporous zeolite Z3 with a pore diameter of 2.4 nm is placed at the bottom of the chamber. Hydrogen gas (green) is stored in the form of hydrogen hydrate in the Z3 pores. (FIG. 1B) The role of zeolite (FAU type) pore diameter on hydrogen solubility compared to the bulk4865-9272-1067.1Page 3 of 49094876-000007WOPTmaterial. The ordering of water molecules in pores spanning 2 to 3 nm leads to approximately 2- fold enhancement of hydrogen solubility. (FIG.1C) The role of concavity of pores with dimensions much smaller than critical nucleus size (~6.82 nm) on shape function. A reduced value of f(m,x) corresponds to a lower Gibbs energy barrier for hydrate nucleation. (FIG. 1D) The role of pore size on the nucleation rate of hydrogen hydrates compared to the bulk medium.

[0013] FIG. 2A - FIG. 2D depicts in accordance with various embodiments of the invention, bonding nature of water molecules probed by FTIR spectroscopy for (FIG. 2A) bulk water and THF and (FIG. 2B) Z3 filled with water and THF solution. Compared to the bulk material, Z3 has fewer DA bonds and more DDAA bonds indicating the formation of ice-like structures at the water-pore wall interface. The ratio of DDAA to DA bonds is 1.57 for Z3 compared to 0.94 for bulk water. (FIG.2C) Pore size distribution (PSD) of Z3. The PSD profile confirms the presence of narrow mesopores, around 2 nm. (FIG. 2D) Powder X-ray diffraction pattern of Z3 confirming the zeolite FAU crystal structure without any detectable impurities.

[0014] FIG. 3A - FIG. 3B depicts in accordance with various embodiments of the invention, (FIG.3A) Temporal pressure of the system during hydrate formation in sample Z3 at 10 bar, which is approximated as a quasi-isobaric process. (FIG.3B) Temporal temperature of the system during hydrate formation in sample Z3 at 10 bar.

[0015] FIG. 4A – FIG. 4C depicts in accordance with various embodiments of the invention, (FIG. 4A) Hydrogen storage capacity of zeolites with various pore dimensions are compared with Z3 offering 2.1% storage capacity, which is the maximum capacity of the cubic hydrogen hydrate structure for 10 mol % THF solution. (FIG.4B) Hydrogen storage capacity of Z3 vs bulk water and THF are shown (Papadimitriou, N. I., Tsimpanogiannis, I. N., Papaioannou, A. T. & Stubos, A. K. Evaluation of the hydrogen-storage capacity of pure H2 and binary H2-THF hydrates with Monte Carlo simulations. Journal of Physical Chemistry C 112, 10294–10302 (2008)), which suggest that storage capacity can be boosted by more than 200 times by Z3 structures. (FIG.4C) Storage capacity of Z3 is compared with other state-of-the-art materials in the pressure range of 4-10 bar. Z3 offers 2-5 times higher storage capacity than the other material structures.

[0016] FIG. 5A – FIG. 5B depicts in accordance with various embodiments of the invention, (FIG. 5A) Hydrogen charging times of various material storage media are compared, and their corresponding pressures are labeled on each bar. (FIG.5B) Hydrogen discharging times4865-9272-1067.1Page 4 of 49094876-000007WOPTof various materials are compared. For some materials, the temperatures in the range of 750 K are required for H2discharge. Sample Z3 provides ambient temperature discharging with short discharging times. The combined fast charging and discharging times with minimal energy makes Z3 a superior material for hydrogen storage.

[0017] FIG. 6A – FIG. 6D depicts in accordance with various embodiments of the invention, Pore size distribution (PSD) of (FIG.6A) zeolite with 1.9 nm pores, (FIG.6B) activated Al2O3, (FIG.6C) zeolite with 2.1 nm pores, and (FIG.6D) nano powder SiO2measured through BET experiments with N2at 77k.

[0018] FIG. 7A – FIG. 7B depicts in accordance with various embodiments of the invention, (FIG. 7A) The role of pore diameter of different materials on hydrogen solubility compared to the bulk material. (FIG.7B) The role of pore diameter of zeolite 13X on hydrogen solubility compared to the bulk material. The ordering of water molecules in 2 nm pore leads to an approximate 2-fold enhancement of hydrogen solubility.

[0019] FIG. 8A – FIG. 8B depicts in accordance with various embodiments of the invention, (FIG.8A) Pore size distribution (PSD) of mesoporous carbon. The PSD profile confirms the presence of some micropores, around 1.8 nm, and narrow mesopores in the region around 2– 3 nm. (FIG.8B) FTIR spectrum of mesoporous carbon filled with water / THF. In comparison with bulk water and THF solution, the ratio of DDAA bonds to DA bonds is 1.10 versus 0.94 for bulk water.

[0020] FIG. 9A – FIG. 9B depicts in accordance with various embodiments of the invention, (FIG.9A) Pore size distribution (PSD) of zeolite 13X, 4 nm. (FIG.9B) FTIR spectrum of zeolite 4 nm filled with water / THF. The ratio of DDAA bonds to DA bonds is 1.25 versus 0.94 for bulk water.

[0021] FIG. 10A – FIG. 10B depicts in accordance with various embodiments of the invention, (FIG.10A) Pore size distribution (PSD) of zeolite 13X with 10 nm pores. (FIG.10B) FTIR spectrum of zeolite (10 nm pores) filled with water / THF. The ratio of DDAA bonds to DA bonds is 1.21 versus 0.94 for bulk water.

[0022] FIG. 11A – FIG. 11C depicts in accordance with various embodiments of the invention, (FIG.11A) Picture of the experimental setup. (FIG.11B) Picture of the experimental setup. (FIG. 11C) Schematic of the experimental setup. The stainless-steel chamber includes 6 ports at the top. The ^ଶ^gas tank is connected to the chamber through a regulator. The pressure4865-9272-1067.1Page 5 of 49094876-000007WOPTtransducer is connected to the top port to measure the pressure of the gas during the experiment. A vacuum pump and safety valve are also connected to the top ports. The other port is used for the thermocouple to measure temperature of the H2storage material (e.g., zeolite) during the experiment. The chamber is connected to a circulating jacket and its temperature is controlled by a refrigerant circulator. Both the thermocouple and pressure transducer are connected to the data acquisition systems, which are connected to the lab computer to record the data.

[0023] FIG. 12A – FIG. 12D depicts in accordance with various embodiments of the invention, (FIG.12A) Pressure-time curve during ^ଶ^hydrate formation in sample Z3 at 6 bar. Two distinct steps of hydrogen dissolution and hydrate nucleation and growth are separated by an induction period. No pressure change suggests a saturation condition in the system. (FIG. 12B) Temperature-time curve for the ^ଶ^hydrate formation in sample Z3 at 6 bar. (FIG.12C) Pressure- time curve during ^ଶ^hydrate formation in sample Z3 at 6 bar. (FIG.12D) Temperature-time curve for the ^ଶ^hydrate formation in sample Z3 at 6 bar.

[0024] FIG. 13A – FIG. 13D depicts in accordance with various embodiments of the invention, (FIG.13A) Pressure-time curve during ^ଶ^hydrate formation in sample Z3 at 8 bar. Two distinct steps of hydrogen dissolution and hydrate nucleation and growth are separated by an induction period. No pressure change suggests a saturation condition in the system. (FIG. 13B) Temperature-time curve for the ^ଶ^hydrate formation in sample Z3 at 8 bar. (FIG.13C) Pressure- time curve during ^ଶ^hydrate formation in sample Z3 at 8 bar. (FIG.13D) Temperature-time curve for the ^ଶ^hydrate formation in sample Z3 at 8 bar.

[0025] FIG. 14A – FIG. 14D depicts in accordance with various embodiments of the invention, (FIG. 14A) Pressure-time curve during ^ଶ^hydrate formation in sample Z3 at 10 bar. Two distinct steps of hydrogen dissolution and hydrate nucleation and growth are separated by an induction period. No pressure change suggests a saturation condition in the system. (FIG. 14B) Temperature-time curve for the ^ଶ^hydrate formation in sample Z3 at 10 bar. (FIG.14C) Pressure- time curve during ^ଶ^hydrate formation in sample Z3 at 10 bar. (FIG. 14D) Temperature-time curve for the ^ଶ^hydrate formation in sample Z3 at 10 bar.

[0026] FIG. 15A – FIG. 15D depicts in accordance with various embodiments of the invention, (FIG.15A) Pressure-time curve during ^ଶ^hydrate formation in sample zeolite 13X with 4 nm pores at 6 bar. Two distinct steps of hydrogen dissolution and hydrate nucleation and growth4865-9272-1067.1Page 6 of 49094876-000007WOPTare separated by an induction period. No pressure change suggests a saturation condition in the system. (FIG.15B) Temperature-time curve for the ^ଶ^hydrate formation in the zeolite sample with 4 nm pores at 6 bar. (FIG.15C) Pressure-time curve during ^ଶ^hydrate formation in sample zeolite 13X with 4 nm pores at 6 bar. (FIG.15D) Temperature-time curve for the ^ଶ^hydrate formation in the zeolite sample with 4 nm pores at 6 bar.

[0027] FIG. 16A – FIG. 16D depicts in accordance with various embodiments of the invention, (FIG.16A) Pressure-time curve during ^ଶ^hydrate formation in zeolite 13X with 4 nm pores at 8 bar. Two distinct steps of hydrogen dissolution and hydrate nucleation and growth are separated by an induction period. No pressure change suggests a saturation condition in the system. (FIG.16B) Temperature-time curve for the ^ଶ^hydrate formation in zeolite 13X with 4 nm pores at 8 bar. (FIG.16C) Pressure-time curve during ^ଶ^hydrate formation in zeolite 13X with 4 nm pores at 8 bar. (FIG. 16D) Temperature-time curve for the ^ଶ^hydrate formation in zeolite 13X with 4 nm pores at 8 bar.

[0028] FIG. 17A – FIG. 17D depicts in accordance with various embodiments of the invention, (FIG.17A) Pressure-time curve during ^ଶ^hydrate formation in zeolite 13X with 4 nm pores at 10 bar. Two distinct steps of hydrogen dissolution and hydrate nucleation and growth are separated by an induction period. No pressure change suggests a saturation condition in the system. (FIG.17B) Temperature-time curve for the ^ଶ^hydrate formation in zeolite 13X with 4 nm pores at 10 bar. (FIG.17C) Pressure-time curve during ^ଶ^hydrate formation in zeolite 13X with 4 nm pores at 10 bar. (FIG. 17D) Temperature-time curve for the ^ଶ^hydrate formation in zeolite 13X with 4 nm pores at 10 bar.

[0029] FIG. 18A – FIG. 18D depicts in accordance with various embodiments of the invention, (FIG.18A) Pressure-time curve during ^ଶ^hydrate formation in zeolite 13X with 10 nm pores at 12 bar. Two distinct steps of hydrogen dissolution and hydrate nucleation and growth are separated by an induction period. No pressure change suggests a saturation condition in the system. (FIG.18B) Temperature-time curve for the ^ଶ^hydrate formation in zeolite 13X with 10 nm pores at 12 bar. (FIG.18C) Pressure-time curve during ^ଶ^hydrate formation in zeolite 13X with 10 nm pores at 12 bar. (FIG. 18D) Temperature-time curve for the ^ଶ^hydrate formation in zeolite 13X with 10 nm pores at 12 bar.4865-9272-1067.1Page 7 of 49094876-000007WOPT

[0030] FIG. 19A – FIG. 19B depicts in accordance with various embodiments of the invention, (FIG.19A) Pressure-time curve during ^ଶ^hydrate formation in zeolite 13X with 10 nm pores at 10 bar. (FIG. 19B) Temperature-time curve for the ^ଶ^hydrate formation in the same zeolite sample at 10 bar.

[0031] FIG. 20A – FIG. 20B depicts in accordance with various embodiments of the invention, (FIG.20A) Pressure-time curve during ^ଶ^hydrate formation in activated carbon with 1.8 nm pores at 11 bar. (FIG. 20B) Temperature-time curve for the ^ଶ^hydrate formation in the same sample at 11 bar. DESCRIPTION OF THE INVENTION

[0032] All references cited herein are incorporated by reference in their entirety as though fully set forth. Unless defined otherwise, technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs.

[0033] One skilled in the art will recognize many methods and materials similar or equivalent to those described herein, which could be used in the practice of the present invention. Other features and advantages of the invention will become apparent from the following detailed description, taken in conjunction with the accompanying drawings, which illustrate, by way of example, various features of embodiments of the invention. Indeed, the present invention is in no way limited to the methods and materials described. For purposes of the present invention, the following terms are defined below. For convenience, certain terms employed herein, in the specification, examples and appended claims are collected here.

[0034] Unless stated otherwise, or implicit from context, the following terms and phrases include the meanings provided below. Unless explicitly stated otherwise, or apparent from context, the terms and phrases below do not exclude the meaning that the term or phrase has acquired in the art to which it pertains. Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. It should be understood that this invention is not limited to the particular methodology, protocols, and reagents, etc., described herein and as such can vary. The definitions and terminology used herein are provided to aid in describing particular embodiments, and are not4865-9272-1067.1Page 8 of 49094876-000007WOPTintended to limit the claimed invention, because the scope of the invention is limited only by the claims.

[0035] As used herein the term “comprising” or “comprises” is used in reference to compositions, methods, systems, articles of manufacture, apparatus, devices, and respective component(s) thereof, that are useful to an embodiment, yet open to the inclusion of unspecified elements, whether useful or not. It will be understood by those within the art that, in general, terms used herein are generally intended as “open” terms (e.g., the term “including” should be interpreted as “including but not limited to,” the term “having” should be interpreted as “having at least,” the term “includes” should be interpreted as “includes but is not limited to,” etc.). Although the open- ended term “comprising,” as a synonym of terms such as including, containing, or having, is used herein to describe and claim the invention, the present invention, or embodiments thereof, may alternatively be described using alternative terms such as “consisting of” or “consisting essentially of.”

[0036] Unless stated otherwise, the terms “a” and “an” and “the” and similar references used in the context of describing a particular embodiment of the application (especially in the context of claims) can be construed to cover both the singular and the plural. The recitation of ranges of values herein is merely intended to serve as a shorthand method of referring individually to each separate value falling within the range. Unless otherwise indicated herein, each individual value is incorporated into the specification as if it were individually recited herein. All methods described herein can be performed in any suitable order unless otherwise indicated herein or otherwise clearly contradicted by context. The use of any and all examples, or exemplary language (for example, “such as”) provided with respect to certain embodiments herein is intended merely to better illuminate the application and does not pose a limitation on the scope of the application otherwise claimed. The abbreviation, “e.g.” is derived from the Latin exempli gratia, and is used herein to indicate a non-limiting example. Thus, the abbreviation “e.g.” is synonymous with the term “for example.” No language in the specification should be construed as indicating any non- claimed element essential to the practice of the application.

[0037] “Optional" or “optionally” means that the subsequently described circumstance may or may not occur, so that the description includes instances where the circumstance occurs and instances where it does not.4865-9272-1067.1Page 9 of 49094876-000007WOPT

[0038] In some embodiments, the numbers expressing quantities of reagents, properties such as concentration, reaction conditions, and so forth, used to describe and claim certain embodiments of the invention are to be understood as being modified in some instances by the term “about.” Accordingly, in some embodiments, the numerical parameters set forth in the written description and attached claims are approximations that can vary depending upon the desired properties sought to be obtained by a particular embodiment. In some embodiments, the numerical parameters should be construed in light of the number of reported significant digits and by applying ordinary rounding techniques. Notwithstanding that the numerical ranges and parameters setting forth the broad scope of some embodiments of the invention are approximations, the numerical values set forth in the specific examples are reported as precisely as practicable. The numerical values presented in some embodiments of the invention may contain certain errors necessarily resulting from the standard deviation found in their respective testing measurements.

[0039] Groupings of alternative elements or embodiments of the invention disclosed herein are not to be construed as limitations. Each group member can be referred to and claimed individually or in any combination with other members of the group or other elements found herein. One or more members of a group can be included in, or deleted from, a group for reasons of convenience and / or patentability. When any such inclusion or deletion occurs, the specification is herein deemed to contain the group as modified thus fulfilling the written description of all Markush groups used in the appended claims.

[0040] In various embodiments, materials of the present invention as disclosed herein may be synthesized using any synthetic method available to one of skill in the art. Non-limiting examples of synthetic methods used to prepare various embodiments of materials of the present invention are disclosed in the Examples section herein.

[0041] Herein, we report a paradigm in the development of sustainable materials for hydrogen storage with a storage capacity of 2.1 wt% at low operating pressure (10 bar) with unprecedented fast charging / discharging rates and discharging at ambient temperature. This material platform stores H2in the form of a hydrogen hydrate with long-term stability.

[0042] Herein, we report a material paradigm in the development of sustainable materials for hydrogen storage with a high storage capacity of 2.1 wt% at 10 bar, surpassing the capacity of current materials by several folds, with fast charging / discharging and ambient temperature4865-9272-1067.1Page 10 of 49094876-000007WOPTdischarging. The material platform is a modified zeolite with rationally tuned pores and modified surface chemistry that exhibits long-term stability and stores hydrogen gas in the form of hydrogen hydrates. The selected pore dimensions enhance the hydrogen solubility through restructuring of water molecules, and the surface chemistry of the material leads to enhanced double donor- acceptor bonds with water molecules for enhanced hydrogen storage capacity. In various embodiments, the material of the present invention addresses long-standing hurdles of high operating pressure and slow formation kinetics of hydrogen hydrates (Florusse, L. J. et al. Stable Low-Pressure Hydrogen Clusters Stored in a Binary Clathrate Hydrate. Science (1979) 306, 469– 471 (2004); Davoodabadi, A., Mahmoudi, A. & Ghasemi, H. The potential of hydrogen hydrate as a future hydrogen storage medium. iScience 24, 101907 (2021); Lee, H. et al. Tuning clathrate hydrates for hydrogen storage. Nature 434, 743–746 (2005)) as a promising green platform for hydrogen storage.

[0043] Hydrogen hydrate functions based on trapping ^ଶmolecules in the lattices structure of host molecules (i.e., water). In comparison with the other methods, hydrogen storage through hydrates has promising advantages including ambient condition discharging, low-cost material, operational safety, and no negative environmental impacts (e.g., no generated pollutant / toxic substances) (Di Profio, P., Arca, S., Rossi, F. & Filipponi, M. Comparison of hydrogen hydrates with existing hydrogen storage technologies: Energetic and economic evaluations. Int J Hydrogen Energy 34, 9173–9180 (2009)). Despite these promising features of hydrogen hydrates, the required high storage pressures and / or low storage temperatures, low storage capacities, and slow charging rates have hindered their commercial deployment. Through a rationally designed morphological and functional material platform, we boosted the storage capacity of hydrates by 200 times and the formation rate by 10 times (Lee, H. et al. Tuning clathrate hydrates for hydrogen storage. Nature 434, 743–746 (2005); Ho, L. N., Schuurman, Y., Farrusseng, D. & Coasne, B. Solubility of Gases in Water Confined in Nanoporous Materials: ZSM-5, MCM-41, and MIL-100. Journal of Physical Chemistry C 119, 21547–21554 (2015)). In various embodiments of the present invention, the hydrogen storage capacity of the developed material is 2-5 times that of state-of-the-art materials at low pressures of 5-12 bar.

[0044] The storage of ^ଶmolecules in hydrate structures occurs through physical entrapment of ^ଶmolecules in water cages as opposed to a chemical reaction. The mechanism is primarily governed by van der Waals (dispersion) forces, intermolecular interactions, and4865-9272-1067.1Page 11 of 49094876-000007WOPThydrogen bonding, where the strong hydrogen bonds hold the host framework together. Phase diagrams of water-hydrogen at a temperature range of 200-330 K and pressures up to 2.5 GPa show various forms of hydrogen hydrates including classical clathrate hydrates with cubic structure II (sII) (unit cell of 136 water molecules + different numbers of hydrogen molecules in large and small cavities), hydrogen-filled ice Ih(unit cell of 64 water molecules with maximum 32 H2molecules), hydrogen-filled ice II (C1 phase, unit cell of 288 water molecules with maximum 48 H2molecules), and hydrogen-filled ice Ic (C2 phase, unit cell of 64 water molecules and 64 H2molecules) (Vos, W. L., Finger, L. W., Hemley, R. J. & Mao, H. Novel H2-H2O clathrates at high pressures. Phys Rev Lett 71, 3150–3153 (1993); Zhdanov, R. K. et al. Phase diagram and composition of water based crystalline phases in hydrogen – Water binary system. Solid State Commun 294, 6–10 (2019)). In addition, it has been shown in previous literature reports that H2could be incorporated in a hydrate with cubic structure (I) (contains two pentagonal dodecahedron (512) cages and six tetrakaidecahedron (51262) cages) (Grim, R. G. et al. Synthesis and Characterization of sI Clathrate Hydrates Containing Hydrogen. The Journal of Physical Chemistry C 116, 18557–18563 (2012)) and hexagonal hydrate structure H (sH) (three pentagonal dodecahedron (512) cages, two irregular dodecahedron (435663) cages, and one icosahedron (51268) cage) (Strobel, T. A., Koh, C. A. & Sloan, E. D. Water Cavities of sH Clathrate Hydrate Stabilized by Molecular Hydrogen. J Phys Chem B 112, 1885–1887 (2008). Each water cage of the host structure usually contains one gas molecule; however, for small molecules like ^ଶ, multiple occupancy is possible. Mostly, the storage of ^ଶin hydrate structures happens at high pressures (e.g., 200 MPa at 273 K) (Qian, G. R., Lyakhov, A. O., Zhu, Q., Oganov, A. R. & Dong, X. Novel hydrogen hydrate structures under pressure. Sci Rep 4, 1–5 (2014)) or low temperatures (e.g., 0.1 MPa at 100K). In previous literature reports, it has been shown that second guest molecules, referred to as promoters, can facilitate hydrate formation at the expense of lower hydrogen storage capacity. For example, Lee et al. (Lee, H. et al. Tuning clathrate hydrates for hydrogen storage. Nature 434, 743–746 (2005)) decreased the required pressure for ^ଶstorage from 200 MPa to 12 MPa by filling the larger cavity (hydrate cages) with tetrahydrofuran (THF) to stabilize the hydrate structure. Through studies of various promoters, it was found that THF is the most efficient second guest molecules for hydrate formation (Davoodabadi, A., Mahmoudi, A. & Ghasemi, H. The potential of hydrogen hydrate as a future hydrogen storage medium. iScience 24, 101907 (2021)). Frankcombe et al. (Frankcombe, T. J. & Kroes, G. J. Molecular dynamics simulations of type-sII4865-9272-1067.1Page 12 of 49094876-000007WOPThydrogen clathrate hydrate close to equilibrium conditions. Journal of Physical Chemistry C 111, 13044–13052 (2007)) performed molecular dynamics (MD) simulations of ^ଶ-containing type-sII hydrate and found two different levels of ^ଶ^mobility. Although no migration of ^ଶ^was observed in small cages, ^ଶwas remarkably mobile in large cages, which can lead to migration of the ^ଶout of the hydrate phase into the gas phase. The presence of promoter molecules, such as THF, leads to their occupation of large cages, which can block ^ଶmigration paths. The ^ଶcontained within the large cages would thus maintain “mechanical” resistance against hydrate cage collapse, which demonstrates the stabilizing effect of promoters.

[0045] Rather than stabilize hydrate formation through a mixture of water, H2gas, and second guest molecules, in various embodiments of the present invention described herein we introduce a host framework material for hydrogen hydrate formation. The framework material has five distinct features: (1) It provides a platform for interfacial hydrate formation rather than bulk hydrate formation; (2) Through rational selection of pore dimensions, the water molecules are layered in the pore of the host material leading to 2-3 times enhanced hydrogen absorption; (3) The curvature of the pores in the host framework enhances the nucleation rate of hydrate particles; and (4) The chemistry of pore surface allows for restructuring of water molecules at the interface leading to the formation of DDAA (double donor-double acceptor bonds) and consequently a high nucleation rate and high hydrogen storage capacity, demonstrated by FTIR spectroscopy. The host material is schematically shown in FIG.1A which is a powder form of zeolite Y synthesized with a pore size of 2.4 nm and a surface area of 1100 m2g-1using a process developed by Garcia- Martinez and coworkers that offers controlled mesoporosity (García-Martínez, J., Johnson, M., Valla, J., Li, K. & Ying, J. Y. Mesostructured zeolite Y—high hydrothermal stability and superior FCC catalytic performance. Catal Sci Technol 2, 987 (2012).; Chawla, A., Linares, N., Rimer, J. D. & García-Martínez, J. Time-Resolved Dynamics of Intracrystalline Mesoporosity Generation in USY Zeolite. Chemistry of Materials 31, 5005–5013 (2019)).

[0046] Herein we refer to this hierarchical FAU-type zeolite as Z3. The procedure for the development of Z3 is provided in the Examples section herein, under the heading titled Materials. The pores are filled with a solution of THF and water with 10 mol% THF concentration. Compared to slow diffusion of hydrogen gas in bulk water for bulk hydrate formation, this structure directs the hydrate formation to confined water in the pores. Furthermore, the aluminosilicate framework of Z3 provides a 3D configuration for hydrogen-gas water interaction rather than the 2D planar4865-9272-1067.1Page 13 of 49094876-000007WOPTinterface of water-H2in a bulk hydrate formation configuration. We examined hydrogen solubility in various pore sizes of a representative zeolite sample (zeolite 13X) through the experimental procedure discussed in the Examples section herein, under the heading titled Hydrogen solubility in various pore sizes. Without limitation, the optimal pore size was found to be 2-3 nm for maximum hydrogen solubility as shown in FIG.1B. In FAU-type zeolite with this pore diameter, the water molecules form an ordered ice-like structure in the pores, which confines gas molecules in the regions of low water density and leads to an approximate 2-fold enhancement of hydrogen solubility in the structured water. Even though gas solubility enhancement is observed in pores a few nm in size, the solubility in 1 nm pores is lower because the high curvature of the surface prevents water from strongly ordering. Conversely, gas solubility in 10 nm pores is almost similar to that in the bulk liquid (Coasne, B. & Farrusseng, D. Gas oversolubility in nanoconfined liquids: Review and perspectives for adsorbent design. Microporous and Mesoporous Materials 288, 109561 (2019); Ho, L. N., Schuurman, Y., Farrusseng, D. & Coasne, B. Solubility of Gases in Water Confined in Nanoporous Materials: ZSM-5, MCM-41, and MIL-100. Journal of Physical Chemistry C 119, 21547–21554 (2015)). For a pore filled with water / THF, hydrogen hydrate nuclei are formed on a concave surface. The high concavity of the zeolite pore walls leads to a drastic drop in the Gibbs energy barrier (ο^כൌ ο^^^^^^^^ǡ ^^^^ for hydrate nucleation through the shape function f(m,x), FIG. 1C. It is noted that the concavity affects the value of x in this function, as discussed in the Examples section herein, under the heading titled Physics of hydrogen hydrate nucleation. Consequently, the reduced shape function and concomitantly the reduced Gibbs energy barrier leads to significant enhancement in the hydrogen hydrate nucleation rate, as shown in FIG.1D.

[0047] The chemistry of the pore surface and its interaction with water plays a critical role in hydrate nucleation and hydrogen storage. In the work described herein, we took advantage of the Si-OH groups of Z3 to activate ice-like bonds at the interface of mesopores (Bregante, D. T. et al. The shape of water in zeolites and its impact on epoxidation catalysis. Nat Catal 4, 797–808 (2021)). The ice-like structure through its effect on interfacial energy, ^, will further enhance the nucleation rate of hydrates. The calculation of m in the shape function is not straightforward, but as the interface of water-Z3 resembles that of the water-ice interface, we expect the value of ^ to approach 1, as discussed in the Examples section herein, under the heading titled Surface energy of the interfaces. Herein, we examined the bonding type of water molecules in the bulk solution of4865-9272-1067.1Page 14 of 49094876-000007WOPTwater / THF and water / THF confined in pores of Z3 through FTIR spectroscopy (FIG.2A and FIG. 2B). We observed that water confined in Z3 pores shows enhanced DDAA bonds compared to DA bonds, suggesting the formation of ice-like structures in the confined water. For the Z3 material, the ratio of DDAA to DA bonds is 1.57, while this ratio is 0.94 for bulk water. We conducted FTIR spectroscopy for commercial zeolites with other pore sizes and for mesoporous carbon as shown in the Examples section herein, under the heading titled Pore dimension distribution and surface chemistry. For all materials examined, we did not observe an enhanced effect of DDAA to DA ratio comparable to that of Z3. For zeolites with 4 nm and 10 nm pores, this ratio drops to 1.25 and 1.21, respectively. For mesoporous carbon, the ratio shows a much lower value of 1.10. FIG. 2C shows a narrow distribution of pore sizes in Z3 and thus confirms the uniformity of the pore dimensions in Z3. Furthermore, we conducted X-ray diffraction of Z3 to confirm its crystallinity (FAU framework type). Overall, the optimal pore size and specific surface chemistry of Z3 enables a decrease in the Gibb’s energy barrier for hydrogen hydrates to nucleate at much lower pressures than in bulk systems.

[0048] In the present invention, we used the developed material framework of Z3 for hydrogen storage through hydrogen hydrates. The experimental platform and procedure are discussed in the Examples section herein under the heading titled Experimental setup for hydrogen storage and the heading titled Experimental procedure for hydrogen storage. The closed system includes water, 10 mol% THF promoter, the material framework, and H2gas. In the system, the material framework is placed at the bottom of the chamber, and the chamber is filled with hydrogen gas to initiate hydrogen storage. As shown in FIG.3A, the hydrate formation occurs in two distinct steps: (i) hydrogen diffusion in water and (ii) hydrate nucleation and growth. These two steps are separated by an induction period. This period is characterized by the time to attain stable hydrate nuclei that can grow continuously into bulk hydrate crystals. As hydrogen gas diffuses in the water or hydrate phase nucleates, the pressure in the chamber drops. This behavior resembles quasi- isobaric conditions at ~10 bar since the pressure change is less than 0.5 bar. The pressure variation in the hydrate formation process within Z3 is shown in FIG.3A. Within 10 min, we observe that the water confined in the pores is fully saturated with hydrogen gas and no further hydrogen can dissolve in the water. For bulk water, based on the diffusion coefficient of hydrogen gas in water (4.5u10-5cm-2s-1) and considering bulk water as a semi-infinite medium, hydrogen molecules4865-9272-1067.1Page 15 of 49094876-000007WOPTdiffuse within 300 ^^ length of bulk water phase suggesting that hydrate formation is limited to approximately this length scale.

[0049] After the induction period, the hydrate phase nucleates at the pore wall-water interface as it is characterized by a drop in hydrogen pressure and a release of heat as indicated by an enthalpic increase in the liquid-solid phase (an exothermic process). We probed the temperature of the system as a function of time for the Z3 sample, as shown in FIG. 3B. We emphasize that control experiments were conducted before each experiment to accurately capture the kinetics of hydrate formation, as described in the Examples section herein under the heading titled Experimental procedure for hydrogen storage. In addition to sample Z3, we probed hydrogen hydrate formation in mesoporous zeolite 13X (FAU type) with pores 4 nm and 10 nm in the course of our work, as described in the Examples section herein under the heading titled Experimental procedure for hydrogen storage. Through integration of the temperature-time curves, we determined the heat released in the system through hydrate formation, as described in the Examples section herein under the heading titled Hydrogen storage capacity. This information along with the enthalpy of phase change allows the determination of hydrogen hydrate formation for each material framework. Having the amount of hydrogen stored through pressure drop curves (FIG. 3A) and the mass of the formed hydrogen hydrate, we determined the hydrogen storage capacity of Z3 and zeolites with other pore sizes (FIG.4A). At a pressure of ~10 bar, Z3 possess a hydrogen storage capacity of 2.1 wt%, which is approaching the maximum storage capacity of cubic hydrogen hydrate structure II for a solution of water and 10 mol% THF (i.e., ~2.1 wt%)32. The storage capacity of 4.1 wt% can be achieved for pure water, but requires a much higher pressure. As we limited the operating pressure range between 4-12 bar in this work, we did not examine hydrogen hydrate formation in pure water. For zeolite 13X with 4 nm pore size, the hydrogen storage capacity is 1.9 wt% at 10 bar. In zeolite 13X with 10 nm pore size, we could not form hydrogen hydrate up to a pressure of 10 bar, but approaching 12 bar, we achieved a hydrogen storage capacity of 1.1 wt%. Without being bound by theory, this finding suggests that hydrogen solubility at few nanometer pores play a critical role for hydrate formation at these low operating pressures. To emphasize the dramatic role of restructuring water molecules in confined spaces and DDAA water bonds for hydrate formation, we compared the hydrogen storage capacity of Z3 with bulk water at various pressures (FIG.4B). The effect of restructuring water and tuning the bonding nature of the water-pore wall enhanced the storage capacity by more than two orders of magnitude.4865-9272-1067.1Page 16 of 49094876-000007WOPTWe should emphasize that we conducted the hydrogen storage experiments with mesoporous carbon of 1.8 nm pore diameter as a control, but no hydrate formation could be measured as described in the Examples section herein under the heading titled Experimental procedure for hydrogen storage; therefore, it is apparent that the combination of optimal pore size and surface chemistry is required to achieve this unprecedented hydrogen storage capacity.

[0050] FIG.4C compares the hydrogen storage capacity of Z3 with other state-of-the-art materials in the operating pressure range of 4-12 bar. We chose this pressure range based on system feasibility for onboard light-duty vehicles and portable power applications. We note further that we limited the temperature range of storage materials to -40 to 85oC based on the DOE target for 2025. Under these ranges of operating conditions, Z3 offers 2-5 times higher storage capacity compared to the state-of-the-art materials and promises a disruptive platform for hydrogen storage technologies. In addition to high storage capacity, Z3 has other advantages on charging / discharging rates compared to the state-of-the-art materials as discussed below.

[0051] The hydrogen charging rate plays an important role in the implementation of hydrogen storage technologies. The charging times of various state-of-the-art materials are shown in FIG.5A. The charging pressure for each material is depicted on each graph. Despite having the lowest charging pressure and highest storage capacity, Z3 surprisingly exhibits the shortest charging time compared to other materials. For most of the materials, the discharging of hydrogen is achieved through high temperatures or under vacuum conditions, which significantly limits the deployment of these structures in various applications. The discharging time of various hydrogen storage materials along with their corresponding discharging temperature is provided in FIG.5B. For some of these materials, temperatures approaching 700 K are required for H2discharging. The mesoporous zeolite Z3 has one of the lowest discharging times at ambient discharging temperature. These performance criteria demonstrate the many advantages and potential utility that Z3 offers as a H2storage material.

[0052] Hydrogen storage systems are crucial to the successful transition to sustainable energy and also offer strategies to address climate challenges. High storage capacity at moderate pressure and temperature, fast charging and discharging along with low-cost and safety are the principle merits of these systems. In various embodiments of the present invention described herein, we introduced a new high-performance material as a paradigm to store hydrogen in the molecular structure of water with no deleterious environmental effects. As water and ice are4865-9272-1067.1Page 17 of 49094876-000007WOPTomnipresent media in nature, the introduced concept has an immense potential to be implemented in large stationary or compact mobile settings. We envision that the localized interfacial and confined hydrogen storage described herein will enable safe hydrogen deployment in a broad spectrum of energy systems from power generation to land and ocean transportation.

[0053] Table 1. Hydrogen storage capacity of zeolites with various pore diameters. Released Enthalpy of Mass of Material sensible hydrate hydrogen Consumed Storage h dro en ca acit

[0005] abe . ydrogen storage capac ty o state-o -t e-art mater a s compared to an embodiment of the present invention Z3. Reference MaterialPressureStorage capacity (bar)(wt%)4865-9272-1067.1Page 18 of 49094876-000007WOPT10 1.5 6 0.19 Reference 6: Zhou, C. & Szpunar, J. A. Hydrogen Storage Performance in Pd / Graphene Nanocomposites. ACS Appl Mater Interfaces 8, 25933–25940 (2016). Reference 7: Zhou, C., Szpunar, J. A. & Cui, X. Synthesis of Ni / Graphene Nanocomposite for Hydrogen Storage. ACS Appl Mater Interfaces 8, 15232–15241 (2016). Reference 8: Morris, L., Trudeau, M. L., Reed, D., Book, D. & Antonelli, D. M. Thermodynamically neutral Kubas-type hydrogen storage using amorphous Cr(iii) alkyl hydride gels. Physical Chemistry Chemical Physics 17, 9480–9487 (2015). Reference 9: Klontzas, E., Tylianakis, E. & Froudakis, G. E. Designing 3D COFs with enhanced hydrogen storage capacity. Nano Lett 10, 452–454 (2010). Reference 10: Lai, Q., Pratthana, C., Yang, Y., Rawal, A. & Aguey-Zinsou, K. F. Nanoconfinement of Complex Borohydrides for Hydrogen Storage. ACS Appl Nano Mater 4, 973– 978 (2021). Reference 11: Liu, S. et al. Hydrogen storage in incompletely etched multilayer Ti2CTx at room temperature. Nat Nanotechnol 16, 331–336 (2021).4865-9272-1067.1Page 19 of 49094876-000007WOPTReference 12: Morris, L. et al. A manganese hydride molecular sieve for practical hydrogen storage under ambient conditions. Energy Environ Sci 12, 1580–1591 (2019). Reference 13: Blankenship, T. S., Balahmar, N. & Mokaya, R. Oxygen-rich microporous carbons with exceptional hydrogen storage capacity. Nat Commun 8, (2017). Reference 14: Lin, K. S., Adhikari, A. K., Su, Y. H., Shu, C. W. & Chan, H. Y. Synthesis, characterization, and hydrogen storage study by hydrogen spillover of MIL-101 metal organic frameworks. in Adsorption vol.18483–491 (2012). Reference 15: Srivastava, S. & Upadhyaya, R. K. Investigations of AB5-type hydrogen storage materials with enhanced hydrogen storage capacity. Int J Hydrogen Energy 36, 7114–7121 (2011). Reference 16: Qin, C. et al. High-pressure hydrogen storage performances of ZrFe2 based alloys with Mn, Ti, and V addition. Int J Hydrogen Energy 45, 9836–9844 (2020).

[0055] Table 3. Charging time of state-of-the-art H2storage materials compared to an embodiment of the present invention Z3. Reference MaterialPressureCharging time (MPa)(h)4865-9272-1067.1Page 20 of 49094876-000007WOPT24 LiNH2 / MgH25 14 Ref, ., , . ., , . ., , . . , M. D. Reversible hydrogen storage by NaAlH4 confined within a titanium-functionalized MOF-74(Mg) nanoreactor. ACS Nano 6, 9807–9817 (2012). Reference 11: Liu, S. et al. Hydrogen storage in incompletely etched multilayer Ti2CTx at room temperature. Nat Nanotechnol 16, 331–336 (2021). Reference 18: Cho, E. S. et al. Graphene oxide / metal nanocrystal multilaminates as the atomic limit for safe and selective hydrogen storage. Nat Commun 7, (2016). Reference 19: Lee, H. et al. Tuning clathrate hydrates for hydrogen storage. Nature 434, 743–746 (2005). Reference 20: Jeon, K. J. et al. Air-stable magnesium nanocomposites provide rapid and high- capacity hydrogen storage without using heavy-metal catalysts. Nat Mater 10, 286–290 (2011). Reference 21: Song, M., Bobet, J.-L. & Darriet, B. Improvement in hydrogen sorption properties of Mg by reactive mechanical grinding with Cr2O3, Al2O3 and CeO2. J Alloys Compd 340, 256– 262 (2002). Reference 22: Prendergast, J. W. Hydrogen desorption and absorption for activated magnesium hydride. (University of Birmingham, 2010). Reference 23: Hu, Y. H. & Ruckenstein, E. Hydrogen storage of Li 2NH prepared by reacting Li with NH 3. Ind Eng Chem Res 45, 182–186 (2006). Reference 24: CHEN, Y., SEQUEIRA, C., CHEN, C., WANG, X. & WANG, Q. Metal hydride beds and hydrogen supply tanks as minitype PEMFC hydrogen sources. Int J Hydrogen Energy 28, 329–333 (2003).4865-9272-1067.1Page 21 of 49094876-000007WOPT

[0056] Table 4. Discharge time of state-of-the-art H2 storage materials compared to an embodiment of the present invention Z3. Reference MaterialTemperatureDischarging time (K)(h)Reference 25: Ward, P. A. et al. Reversible hydrogen storage in a LiBH4-C60 nanocomposite. Journal of Physical Chemistry C 117, 22569–22575 (2013). Reference 22: Prendergast, J. W. Hydrogen desorption and absorption for activated magnesium hydride. (University of Birmingham, 2010).4865-9272-1067.1Page 22 of 49094876-000007WOPTReference 21: Song, M., Bobet, J.-L. & Darriet, B. Improvement in hydrogen sorption properties of Mg by reactive mechanical grinding with Cr2O3, Al2O3 and CeO2. J Alloys Compd 340, 256– 262 (2002). Reference 24: CHEN, Y., SEQUEIRA, C., CHEN, C., WANG, X. & WANG, Q. Metal hydride beds and hydrogen supply tanks as minitype PEMFC hydrogen sources. Int J Hydrogen Energy 28, 329–333 (2003). Reference 23: Hu, Y. H. & Ruckenstein, E. Hydrogen storage of Li 2NH prepared by reacting Li with NH 3. Ind Eng Chem Res 45, 182–186 (2006). Reference 26: CHEN, Y., WU, C., WANG, P. & CHENG, H. Structure and hydrogen storage property of ball-milled LiNH2 / MgH2LiNH2 / MgH2 mixture. Int J Hydrogen Energy 31, 1236– 1240 (2006). Reference 19: Lee, H. et al. Tuning clathrate hydrates for hydrogen storage. Nature 434, 743–746 (2005). Reference 27: Yu, X. B., Granty, D. M. & Walker, G. S. Low-temperature dehydrogenation of LiBH4 through destabilization with TiO2. Journal of Physical Chemistry C 112, 11059–11062 (2008). Reference 11: Liu, S. et al. Hydrogen storage in incompletely etched multilayer Ti2CTx at room temperature. Nat Nanotechnol 16, 331–336 (2021). Reference 28: Ahmad, M., Rafi-Ud-din, Pan, C. & Zhu, J. Investigation of hydrogen storage capabilities of ZnO-based nanostructures. Journal of Physical Chemistry C 114, 2560–2565 (2010). Reference 29: Papadimitriou, N. I., Tsimpanogiannis, I. N., Peters, C. J., Papaioannou, A. T. & Stubos, A. K. Hydrogen storage in sH hydrates: A Monte Carlo study. Journal of Physical Chemistry B 112, 14206–14211 (2008). Reference 30: Hügle, T., Kühnel, M. F. & Lentz, D. Hydrazine borane: A promising hydrogen storage material. J Am Chem Soc 131, 7444–7446 (2009). Reference 31: Gosalawit-Utke, R. et al. LiF-MgB2 system for reversible hydrogen storage. Journal of Physical Chemistry C 114, 10291–10296 (2010).

[0057] Various Non-Limiting Embodiments of the Invention

[0058] Non-Limiting Embodiments include those listed below.4865-9272-1067.1Page 23 of 49094876-000007WOPT

[0059] Embodiment 1. A hydrogen storage device, comprising: a container; and a host framework material.

[0060] Embodiment 2. The device of embodiment 1, further comprising at least one promoter.

[0061] Embodiment 3. The device of embodiment 2, wherein the at least one promoter is water, tetrahydrofuran (THF), or a combination thereof.

[0062] Embodiment 4. The device of any one of embodiments 1-3, further comprising hydrogen gas.

[0063] Embodiment 5. The deice of any one of embodiments 1-4, further comprising at least one hydrogen hydrate.

[0064] Embodiment 6. The device of any one of embodiments 1-5, wherein the host framework material comprises a porous material.

[0065] Embodiment 7. The device of embodiment 6, wherein the porous material comprises nanopores.

[0066] Embodiment 8. The device of embodiment 6 or embodiment 7, wherein the porous material comprises mesopores.

[0067] Embodiment 9. The device of any one of embodiments 6-8, wherein the porous material comprises pores having a diameter of about 1 nm to about 50 nm.

[0068] Embodiment 10. The device of any one of embodiments 6-9, wherein the porous material is a mesoporous material.

[0069] Embodiment 11. The device of any one of embodiments 6-10, wherein the porous material is a zeolite.

[0070] Embodiment 12. The device of embodiment 11, wherein the zeolite has a FAU crystal structure.

[0071] Embodiment 13. The device of embodiment 11 or embodiment 12, wherein the zeolite is a modified zeolite Y.

[0072] Embodiment 14. The device of embodiment 13, wherein the modified zeolite Y comprises a pore size of 2.4 nm and a surface area of 1100 m2g-1.

[0073] Embodiment 15. The device of embodiment 13 or embodiment 14, wherein the modified zeolite Y comprises nanopores.4865-9272-1067.1Page 24 of 49094876-000007WOPT

[0074] Embodiment 16. The device of any one of embodiments 13-15, wherein the modified zeolite Y comprises mesopores.

[0075] Embodiment 17. The device of any one of embodiments 6-10, wherein the porous material is a mesoporous zeolite.

[0076] Embodiment 18. The device of embodiment 17, wherein the mesoporous zeolite has a FAU crystal structure.

[0077] Embodiment 19. The device of embodiment 17 or embodiment 18, wherein the mesoporous zeolite is a modified zeolite Y.

[0078] Embodiment 20. The device of embodiment 19, wherein the modified zeolite Y comprises a pore size of 2.4 nm and a surface area of 1100 m2g-1.

[0079] Embodiment 21. The device of embodiment 19 or embodiment 20, wherein the modified zeolite Y comprises nanopores.

[0080] Embodiment 22. The device of any one of embodiments 19-21, wherein the modified zeolite Y comprises mesopores.

[0081] Embodiment 23. The device of any one of embodiments 1-22, wherein the device has a charging time of 0.16 hours at a pressure of 10 bar.

[0082] Embodiment 24. The device of any one of embodiments 1-23, wherein the device has a storage capacity of about 1.23 wt% to about 2.1 wt% at a pressure of about 6 bar to about 10 bar.

[0083] Embodiment 25. The device of any one of embodiments 1-23, wherein the device has a storage capacity of 2.1 wt% at a pressure of 10 bar, and wherein the device has a storage capacity of 1.7 wt% at a pressure of 8 bar, and wherein the device has a storage capacity of 1.23 wt% at a pressure of 6 bar.

[0084] Embodiment 26. The device of any one of embodiments 1-25, wherein the device has a discharge time of 1.42 hours at a temperature of 273 K.

[0085] Embodiment 27. A method of storing hydrogen, the method comprising: introducing hydrogen gas into a device of any one of embodiments 1-26 under conditions suitable for the storage of hydrogen gas.

[0086] Embodiment 28. The method of embodiment 27, wherein the hydrogen gas is stored in the form of at least one hydrogen hydrate.4865-9272-1067.1Page 25 of 49094876-000007WOPT

[0087] Embodiment 29. A method for storing hydrogen, the method comprising: introducing hydrogen gas into a device of any one of embodiments 1-26 under conditions suitable for the formation of at least one hydrogen hydrate.

[0088] Embodiment 30. A material for storing hydrogen, the material comprising: a modified zeolite Y.

[0089] Embodiment 31. The material of embodiment 30, wherein the modified zeolite Y comprises a pore size of a pore size of 2.4 nm and a surface area of 1100 m2g-1.

[0090] Embodiment 32. The material of embodiment 30 or embodiment 31, wherein the modified zeolite Y is a powder.

[0091] Embodiment 33. The material of any one of embodiments 30-32, wherein the modified zeolite Y has any geometric shape.

[0092] Embodiment 34. The material of any one of embodiments 30-33, wherein the modified zeolite Y has at least one concave surface.

[0093] Embodiment 35. The material of any one of embodiments 30-34, wherein the modified zeolite Y comprises nanopores.

[0094] Embodiment 36. The material of any one of embodiments 30-35, wherein the modified zeolite Y comprises mesopores.

[0095] Embodiment 37. A device for forming and / or storing hydrogen hydrate, comprising: a container; and a host framework material.

[0096] Embodiment 38. The device of embodiment 37, further comprising at least one promoter.

[0097] Embodiment 39. The device of embodiment 38, wherein the at least one promoter is water, tetrahydrofuran (THF), or a combination thereof.

[0098] Embodiment 40. The device of any one of embodiments 37-39, further comprising hydrogen gas.

[0099] Embodiment 41. The device of any one of embodiments 37-40, further comprising at least one hydrogen hydrate.

[0100] Embodiment 42. The device of any one of embodiments 37-41, wherein the host framework material comprises a porous material.

[0101] Embodiment 43. The device of embodiment 42, wherein the porous material comprises nanopores.4865-9272-1067.1Page 26 of 49094876-000007WOPT

[0102] Embodiment 44. The device of embodiment 42 or embodiment 43, wherein the porous material comprises mesopores.

[0103] Embodiment 45. The device of any one of embodiments 42-44, wherein the porous material comprises pores having a diameter of amount 1 nm to about 50 nm.

[0104] Embodiment 46. The device of any one of embodiments 42-45, wherein the porous material is a mesoporous material.

[0105] Embodiment 47. The device of any one of embodiments 42-46, wherein the porous material is a zeolite.

[0106] Embodiment 48. The device of embodiment 47, wherein the zeolite has a FAU crystal structure.

[0107] Embodiment 49. The device of embodiment 47 or embodiment 48, wherein the zeolite is a modified zeolite Y.

[0108] Embodiment 50. The device of embodiment 49, wherein the modified zeolite Y comprises a pore size of 2.4 nm and a surface area of 1100 m2g-1.

[0109] Embodiment 51. The device of embodiment 49 or embodiment 50, wherein the modified zeolite Y comprises nanopores.

[0110] Embodiment 52. The device of any one of embodiments 49-51, wherein the modified zeolite Y comprises mesopores.

[0111] Embodiment 53. The device of any one of embodiments 42-46, wherein the porous material is a mesoporous zeolite.

[0112] Embodiment 54. The device of embodiment 53, wherein the mesoporous zeolite has a FAU crystal structure.

[0113] Embodiment 55. The device of embodiment 53 or embodiment 54, wherein the mesoporous zeolite is a modified zeolite Y.

[0114] Embodiment 56. The device of embodiment 55, wherein the modified zeolite Y comprises a pore size of 2.4 nm and a surface area of 1100 m2g-1.

[0115] Embodiment 57. The device of embodiment 55 or embodiment 56, wherein the modified zeolite Y comprises nanopores.

[0116] Embodiment 58. The device of embodiments 55-57, wherein the modified zeolite Y comprises mesopores.4865-9272-1067.1Page 27 of 49094876-000007WOPT

[0117] Embodiment 59. The device of any one of embodiments 37-58, wherein the device has a charging time of 0.16 hours at a pressure of 10 bar.

[0118] Embodiment 60. The device of any one of embodiments 37-59, wherein the device has a storage capacity of about 1.23 wt% to about 2.1 wt% at a pressure of about 6 bar to about 10 bar.

[0119] Embodiment 61. The device of any one of embodiments 37-59, wherein the device has a storage capacity of 2.1 wt% at a pressure of 10 bar, and wherein the device has a storage capacity of 1.7 wt% at a pressure of 8 bar, and wherein the device has storage capacity of 1.23 wt% at a pressure of 6 bar.

[0120] Embodiment 62. The device of any one of embodiments 37-61, wherein the device has a discharge time of 1.42 hours at a temperature of 273 K.

[0121] Embodiment 63. A method for forming at least one hydrogen hydrate, the method comprising: introducing hydrogen gas into a device of any one of embodiments 37-62 under conditions suitable for the formation of at least one hydrogen hydrate.

[0122] Embodiment 64. A material for forming hydrogen hydrate, comprising: a modified zeolite Y.

[0123] Embodiment 65. The material of embodiment 64, wherein the modified zeolite Y comprises a pore size of 2.4 nm and a surface area of 1100 m2g-1.

[0124] Embodiment 66. The material of embodiment 64 or embodiment 65, wherein the modified zeolite Y is a powder.

[0125] Embodiment 67. The material of any one of embodiments 64-66, wherein the modified zeolite Y has any geometric shape.

[0126] Embodiment 68. The material of any one of embodiments 64-67, wherein the modified zeolite Y has at least one concave surface.

[0127] Embodiment 69. The material of any one of embodiments 64-68, wherein the modified zeolite Y comprises nanopores.

[0128] Embodiment 70. The material of any one of embodiments 64-69, wherein the modified zeolite Y comprises mesopores.

[0129] Embodiment 71. A system for storing hydrogen, comprising: a container; and a host framework material.4865-9272-1067.1Page 28 of 49094876-000007WOPT

[0130] Embodiment 72. The system of embodiment 71, further comprising at least one promoter.

[0131] Embodiment 73. The system of embodiment 72, wherein the at least one promoter is water, tetrahydrofuran (THF), or a combination thereof.

[0132] Embodiment 74. The system of any one of embodiments 71-73, further comprising hydrogen gas.

[0133] Embodiment 75. The system of any one of embodiments 71-74, further comprising at least one hydrogen hydrate.

[0134] Embodiment 76. The system of any one of embodiments 71-75, wherein the host framework material comprises a porous material.

[0135] Embodiment 77. The system of embodiment 76, wherein the porous material comprises nanopores.

[0136] Embodiment 78. The system of embodiment 76 or embodiment 77, wherein the porous material comprises mesopores.

[0137] Embodiment 79. The system of any one of embodiments 76-78, wherein the porous material comprises pores having a diameter of about 1 nm to about 50 nm.

[0138] Embodiment 80. The system of any one of embodiments 76-79, wherein the porous material is a mesoporous material.

[0139] Embodiment 81. The system of any one of embodiments 76-80, wherein the porous material is a zeolite.

[0140] Embodiment 82. The system of embodiment 81, wherein the zeolite has a FAU crystal structure.

[0141] Embodiment 83. The system of embodiment 81 or embodiment 82, wherein the zeolite is a modified zeolite Y.

[0142] Embodiment 84. The system of embodiment 83, wherein the modified zeolite Y comprises a pore size of 2.4 nm and a surface area of 1100 m2g-1.

[0143] Embodiment 85. The system of embodiment 83 or embodiment 84, wherein the modified zeolite Y comprises nanopores.

[0144] Embodiment 86. The system of any one of embodiments 83-85, wherein the modified zeolite Y comprises mesopores.4865-9272-1067.1Page 29 of 49094876-000007WOPT

[0145] Embodiment 87. The system of any one of embodiments 76-80, wherein the porous material is a mesoporous zeolite.

[0146] Embodiment 88. The system of embodiment 87, wherein the mesoporous zeolite has a FAU crystal structure.

[0147] Embodiment 89. The system of embodiment 87 or embodiment 88, wherein the mesoporous zeolite is a modified zeolite Y.

[0148] Embodiment 90. The system of embodiment 89, wherein the modified zeolite Y has a pore size of 2.4 nm and a surface area of 1100 m2g-1.

[0149] Embodiment 91. The system of embodiment 89 or embodiment 90, wherein the modified zeolite Y comprises nanopores.

[0150] Embodiment 92. The system of any one of embodiments 89-91, wherein the modified zeolite Y comprises mesopores.

[0151] Embodiment 93. The system of any one of embodiments 71-92, wherein the device has a charging time of 0.16 hours at a pressure of 10 bar.

[0152] Embodiment 94. The system of any one of embodiments 71-93, wherein the device has a storage capacity of about 1.23 wt% to about 2.1 wt% at a pressure of about 6 bar to about 10 bar.

[0153] Embodiment 95. The system of any one of embodiments 71-93, wherein the device has a storage capacity of 2.1 wt% at a pressure of 10 bar, and wherein the device has a storage capacity of 1.7 wt% at a pressure of 8 bar, and wherein the device has a storage capacity of 1.23 wt% at a pressure of 6 bar.

[0154] Embodiment 96. The system of any one of embodiments 71-95, wherein the device has a discharge time of 1.42 hours at a temperature of 273 K.

[0155] Embodiment 97. A method of storing hydrogen, the method comprising: introducing hydrogen gas into a system of any one of embodiments 71-96 under conditions suitable for the storage of hydrogen gas.

[0156] Embodiment 98. The method of embodiment 97, wherein the hydrogen gas is stored in the form of at least one hydrogen hydrate.

[0157] Embodiment 99. A method for storing hydrogen, the method comprising: introducing hydrogen gas into a system of any one of embodiments 71-96 under conditions suitable for the formation of at least one hydrogen hydrate.4865-9272-1067.1Page 30 of 49094876-000007WOPT

[0158] Additional non-limiting embodiments include those listed below:

[0159] In various embodiments of the present invention, the modified zeolite Y is referred to herein as Z3.

[0160] In various embodiments, the present invention provides a material for storing hydrogen, the material comprising: a mesoporous zeolite. In some embodiments, the mesoporous zeolite is a modified zeolite Y. In some embodiments, the modified zeolite y comprises a pore size of 2.4 nm and a surface area of 1100 m2g-1. In some embodiments, the modified zeolite Y is a powder. In some embodiments, the modified zeolite Y has any geometric shape. In some embodiments, the modified zeolite Y has at least one concave surface. In some embodiments, the modified zeolite Y comprises nanopores. In some embodiments, the modified zeolite y comprises mesopores.

[0161] In various embodiments, the present invention provides a material for forming hydrogen hydrate, comprising: a mesoporous zeolite. In some embodiments, the mesoporous zeolite is a modified zeolite Y. In some embodiments, the modified zeolite y comprises a pore size of 2.4 nm and a surface area of 1100 m2g-1. In some embodiments, the modified zeolite Y is a powder. In some embodiments, the modified zeolite Y has any geometric shape. In some embodiments, the modified zeolite y has at least one concave surface. In some embodiments, the modified zeolite Y comprises nanopores. In some embodiments, the modified zeolite Y comprises mesopores. In some embodiments, the material further comprises at least one promoter. In some embodiments, the at least one promoter is water, tetrahydrofuran (THF), or a combination thereof. In some embodiments, the at least one promoter is tetrahydrofuran (THF), or tetrahydrothiophene (THT), or a combination thereof. In some embodiments, the at least one promoter is water, tetrahydrofuran (THF), tetrahydrothiophene (THT), or a combination thereof. In some embodiments, the at least one promoter is tetrahydrofuran (THF).

[0162] In various embodiments, the present invention provides a method for forming at least one hydrogen hydrate, the method comprising: contacting hydrogen gas with a mesoporous zeolite under conditions suitable for the formation of at least one hydrogen hydrate. In some embodiments, the hydrogen gas is contacted with the mesoporous zeolite in the presence of a at least one promotor. In some embodiments, the at least one promoter is water, tetrahydrofuran (THF), or a combination thereof. In some embodiments, the mesoporous zeolite is a modified zeolite Y. In some embodiments, the modified zeolite Y comprises a pore size of 2.4 nm and a4865-9272-1067.1Page 31 of 49094876-000007WOPTsurface area of 1100 m2g-1. In some embodiments, the modified zeolite y is a powder. In some embodiments, the modified zeolite Y has any geometric shape. In some embodiments, the modified zeolite Y has at least one concave surface. In some embodiments, the modified zeolite Y comprises nanopores. In some embodiments, the modified zeolite Y comprises mesopores. In some embodiments, the at least one promoter is tetrahydrofuran (THF), or tetrahydrothiophene (THT), or a combination thereof. In some embodiments, the at least one promoter is water, tetrahydrofuran (THF), tetrahydrothiophene (THT), or a combination thereof. In some embodiments, the at least one promoter is tetrahydrofuran (THF).

[0163] In some embodiments, the mesopores have a pore size of about 1.0 nm to about 50.0 nm in diameter, or any value in this range. In some embodiments, the mesopores have a pore size of about 2.0 nm to about 50.0 nm in diameter, or any value in this range. In some embodiments, the mesopores have a pore size of 1.0 nm to 50.0 nm in diameter, or any value in this range. In some embodiments, the mesopores have a pore size of 2.0 nm to 50.0 nm in diameter, or any value in this range. In some embodiments, the mesopores have a pore size of 1.0 nm, 2.0 nm, 3.0 nm, 4.0 nm, 5.0 nm, 6.0 nm, 7.0 nm, 8.0 nm, 9.0 nm, 10.0 nm, 11.0 nm, 12.0 nm, 13.0 nm, 14.0 nm, 15.0 nm, 16.0 nm, 17.0 nm, 18.0 nm, 19.0 nm, 20.0 nm, 21.0 nm, 22.0 nm, 23.0 nm, 24.0 nm, 25.0 nm, 26.0 nm, 27.0 nm, 28.0 nm, 29.0 nm, 30.0 nm, 31.0 nm, 32.0 nm, 33.0 nm, 34.0 nm, 35.0 nm, 36.0 nm, 37.0 nm, 38.0 nm, 39.0 nm, 40.0 nm, 41.0 nm, 42.0 nm, 43.0 nm, 44.0 nm, 45.0 nm, 46.0 nm, 47.0 nm, 48.0 nm, 49.0 nm, or 50.0 nm in diameter.

[0164] In some embodiments, the mesopores have a pore size of about 1.0 nm to about 50.0 nm, or any value in this range. In some embodiments, the mesopores have a pore size of about 2.0 nm to about 50.0 nm, or any value in this range. In some embodiments, the mesopores have a pore size of 1.0 nm to 50.0 nm, or any value in this range. In some embodiments, the mesopores have a pore size of 2.0 nm to 50.0 nm, or any value in this range. In some embodiments, the mesopores have a pore size of 1.0 nm, 2.0 nm, 3.0 nm, 4.0 nm, 5.0 nm, 6.0 nm, 7.0 nm, 8.0 nm, 9.0 nm, 10.0 nm, 11.0 nm, 12.0 nm, 13.0 nm, 14.0 nm, 15.0 nm, 16.0 nm, 17.0 nm, 18.0 nm, 19.0 nm, 20.0 nm, 21.0 nm, 22.0 nm, 23.0 nm, 24.0 nm, 25.0 nm, 26.0 nm, 27.0 nm, 28.0 nm, 29.0 nm, 30.0 nm, 31.0 nm, 32.0 nm, 33.0 nm, 34.0 nm, 35.0 nm, 36.0 nm, 37.0 nm, 38.0 nm, 39.0 nm, 40.0 nm, 41.0 nm, 42.0 nm, 43.0 nm, 44.0 nm, 45.0 nm, 46.0 nm, 47.0 nm, 48.0 nm, 49.0 nm, or 50.0 nm.4865-9272-1067.1Page 32 of 49094876-000007WOPT

[0165] In some embodiments, the pores have a pore size of 1.0 nm to 50.0 nm, or any value in this range. In some embodiments, the pores have a pore size of 2.0 nm to 50.0 nm, or any value in this range. In some embodiments, the pores have a pore size of 1.0 nm, 2.0 nm, 3.0 nm, 4.0 nm, 5.0 nm, 6.0 nm, 7.0 nm, 8.0 nm, 9.0 nm, 10.0 nm, 11.0 nm, 12.0 nm, 13.0 nm, 14.0 nm, 15.0 nm, 16.0 nm, 17.0 nm, 18.0 nm, 19.0 nm, 20.0 nm, 21.0 nm, 22.0 nm, 23.0 nm, 24.0 nm, 25.0 nm, 26.0 nm, 27.0 nm, 28.0 nm, 29.0 nm, 30.0 nm, 31.0 nm, 32.0 nm, 33.0 nm, 34.0 nm, 35.0 nm, 36.0 nm, 37.0 nm, 38.0 nm, 39.0 nm, 40.0 nm, 41.0 nm, 42.0 nm, 43.0 nm, 44.0 nm, 45.0 nm, 46.0 nm, 47.0 nm, 48.0 nm, 49.0 nm, or 50.0 nm.

[0166] In some embodiments, the pores have a diameter of about 1.0 nm to about 50 nm, or any value in this range. In some embodiments, the pores have a diameter of about 2.0 nm to about 50 nm, or any value in this range. In some embodiments, the pores have a diameter of 1.0 nm to 50 nm, or any value in this range. In some embodiments, the pores have a diameter of 2.0 nm to 50 nm, or any value in this range. In some embodiments, the pores have a diameter of 1.0 nm, 2.0 nm, 3.0 nm, 4.0 nm, 5.0 nm, 6.0 nm, 7.0 nm, 8.0 nm, 9.0 nm, 10.0 nm, 11.0 nm, 12.0 nm, 13.0 nm, 14.0 nm, 15.0 nm, 16.0 nm, 17.0 nm, 18.0 nm, 19.0 nm, 20.0 nm, 21.0 nm, 22.0 nm, 23.0 nm, 24.0 nm, 25.0 nm, 26.0 nm, 27.0 nm, 28.0 nm, 29.0 nm, 30.0 nm, 31.0 nm, 32.0 nm, 33.0 nm, 34.0 nm, 35.0 nm, 36.0 nm, 37.0 nm, 38.0 nm, 39.0 nm, 40.0 nm, 41.0 nm, 42.0 nm, 43.0 nm, 44.0 nm, 45.0 nm, 46.0 nm, 47.0 nm, 48.0 nm, 49.0 nm, or 50.0 nm.

[0167] In some embodiments, the activated hydrogen storage material is contacted with the hydrogen gas at a pressure of about 4 bar to about 12 bar, or any value in this range. In some embodiments, the activated hydrogen storage material is contacted with the hydrogen gas at a pressure of 4 bar to 12 bar, or any value in this range. In some embodiments, the activated hydrogen storage material is contacted with the hydrogen gas at a pressure of 4 bar, 5 bar, 6, bar, 7 bar, 8 bar, 9 bar, 10 bar, 11 bar, or 12 bar.

[0168] In some embodiments, the hydrogen storage material is contacted with the hydrogen gas at a pressure of about 4 bar to about 12 bar, or any value in this range. In some embodiments, the hydrogen storage material is contacted with the hydrogen gas at a pressure of 4 bar to 12 bar, or any value in this range. In some embodiments, the hydrogen storage material is contacted with the hydrogen gas at a pressure of 4 bar, 5 bar, 6, bar, 7 bar, 8 bar, 9 bar, 10 bar, 11 bar, or 12 bar.4865-9272-1067.1Page 33 of 49094876-000007WOPT

[0169] In some embodiments, the porous material is a mesoporous zeolite, mesoporous silica, mesoporous metal oxide, or mesoporous metal nitride.

[0170] Additional non-limiting embodiments include those listed below:

[0171] Embodiment 100. A hydrogen storage material, the hydrogen storage material comprising: a mesoporous zeolite, wherein the mesoporous zeolite comprises a plurality of mesopores.

[0172] Embodiment 101. The hydrogen storage material of embodiment 100, wherein the mesoporous zeolite is a modified zeolite Y.

[0173] Embodiment 102. The hydrogen storage material of embodiment 100, wherein the plurality of mesopores have a pore size of 1.0 nm to 50.0 nm.

[0174] Embodiment 103. The hydrogen storage material of embodiment 102, wherein the pore size is 2.0 nm to 3.0 nm.

[0175] Embodiment 104. The hydrogen storage material of embodiment 102, wherein the pore size is 2.4 nm.

[0176] Embodiment 105. The hydrogen storage material of embodiment 100, wherein the mesoporous zeolite comprises a surface area of 1100 m2g-1.

[0177] Embodiment 106. The hydrogen storage material of embodiment 100, wherein the mesoporous zeolite is a powder.

[0178] Embodiment 107. The hydrogen storage material of embodiment 100, wherein the mesoporous zeolite comprises at least one concave surface.

[0179] Embodiment 108. The hydrogen storage material of embodiment 100, wherein the mesoporous zeolite comprises an aluminosilicate framework.

[0180] Embodiment 109. The hydrogen storage material of embodiment 100, wherein the mesoporous zeolite comprises a FAU crystal structure.

[0181] Embodiment 110. The hydrogen storage material of embodiment 100, wherein the mesoporous zeolite comprises a hydrogen storage capacity of about 1.23 wt% to about 2.1 wt% based on the total weight of the mesoporous zeolite at a pressure of about 6 bar to about 10 bar.

[0182] Embodiment 111. The hydrogen storage material of embodiment 100, wherein the mesoporous zeolite has a hydrogen charging time of 0.16 hours at a pressure of 10 bar.4865-9272-1067.1Page 34 of 49094876-000007WOPT

[0183] Embodiment 112. The hydrogen storage material of embodiment 100, wherein the mesoporous zeolite has a hydrogen discharging time of 1.42 hours at a temperature of 273 K.

[0184] Embodiment 113. A hydrogen storage system, comprising: an inlet port; a reaction chamber, wherein the reaction chamber is in communication with the inlet port, and wherein the reaction chamber contains a hydrogen storage material of embodiment 100; and an outlet port, wherein the outlet port is in communication with the reaction chamber.

[0185] Embodiment 114. The hydrogen storage system of embodiment 113, wherein the reaction chamber further contains water, or at least one promoter, or both water and at least one promoter.

[0186] Embodiment 115. The hydrogen storage system of claim 113, wherein the at least one promoter is tetrahydrofuran (THF) or tetrahydrothiophene (THT).

[0187] Embodiment 116. A method for storing hydrogen, the method comprising: providing a hydrogen storage material of embodiment 100; providing water, or at least one promoter, or both water and at least one promoter; contacting the hydrogen storage material with the water, the at least one promoter, or both; filling at least a portion of the plurality of mesopores of the hydrogen storage material with the water, the at least one promoter, or both to provide an activated hydrogen storage material; and contacting the activated hydrogen storage material with hydrogen gas under conditions suitable for storing hydrogen in at least a portion of the plurality of mesopores of the hydrogen storage material.

[0188] Embodiment 117. The method of embodiment 116, wherein the at least one promoter is tetrahydrofuran (THF) or tetrahydrothiophene (THT).

[0189] Embodiment 118. The method of embodiment 116, wherein the hydrogen gas is stored in the form of at least one hydrogen hydrate in at least a portion of the plurality of mesopores of the hydrogen storage material.

[0190] Embodiment 119. The method of embodiment 116, wherein the activated hydrogen storage material is contacted with the hydrogen gas at a pressure of about 4 bar to about 12 bar.

[0191] Additional non-limiting embodiments include those listed below:

[0192] Embodiment 120. A hydrogen storage material, the hydrogen storage material comprising: a mesoporous zeolite, wherein the mesoporous zeolite comprises a plurality of mesopores.4865-9272-1067.1Page 35 of 49094876-000007WOPT

[0193] Embodiment 121. The hydrogen storage material of embodiment 120, wherein the mesoporous zeolite is a modified zeolite Y.

[0194] Embodiment 122. The hydrogen storage material of embodiment 120, wherein the plurality of mesopores have a pore size of 1.0 nm to 50.0 nm.

[0195] Embodiment 123. The hydrogen storage material of embodiment 122, wherein the pore size is 2.0 nm to 3.0 nm, or wherein the pore size is 2.4 nm

[0196] Embodiment 124. The hydrogen storage material of embodiment 120, wherein the mesoporous zeolite comprises a surface area of 1100 m2g-1.

[0197] Embodiment 125. The hydrogen storage material of embodiment 120, wherein the mesoporous zeolite is a powder.

[0198] Embodiment 126. The hydrogen storage material of embodiment 120, wherein the mesoporous zeolite comprises at least one concave surface.

[0199] Embodiment 127. The hydrogen storage material of embodiment 120, wherein the mesoporous zeolite comprises an aluminosilicate framework, or wherein the mesoporous zeolite comprises a FAU crystal structure.

[0200] Embodiment 128. The hydrogen storage material of embodiment 120, wherein the mesoporous zeolite comprises a hydrogen storage capacity of about 1.23 wt% to about 2.1 wt% based on the total weight of the mesoporous zeolite at a pressure of about 6 bar to about 10 bar.

[0201] Embodiment 129. The hydrogen storage material of embodiment 120, wherein the mesoporous zeolite has a hydrogen charging time of 0.16 hours at a pressure of 10 bar, or wherein the mesoporous zeolite has a hydrogen discharging time of 1.42 hours at a temperature of 273 K.

[0202] Embodiment 130. A hydrogen storage system, comprising: an inlet port; a reaction chamber, wherein the reaction chamber is in communication with the inlet port, and wherein the reaction chamber contains a hydrogen storage material of embodiment 120; and an outlet port, wherein the outlet port is in communication with the reaction chamber.

[0203] Embodiment 131. The hydrogen storage system of embodiment 130, wherein the reaction chamber further contains water, or at least one promoter, or both water and at least one promoter.

[0204] Embodiment 132. The hydrogen storage system of embodiment 131, wherein the at least one promoter is tetrahydrofuran (THF) or tetrahydrothiophene (THT).4865-9272-1067.1Page 36 of 49094876-000007WOPT

[0205] Embodiment 133. A method for storing hydrogen, the method comprising: providing a hydrogen storage material of embodiment 120; providing water, or at least one promoter, or both water and at least one promoter; contacting the hydrogen storage material with the water, the at least one promoter, or both; filling at least a portion of the plurality of mesopores of the hydrogen storage material with the water, the at least one promoter, or both to provide an activated hydrogen storage material; and contacting the activated hydrogen storage material with hydrogen gas under conditions suitable for storing hydrogen in at least a portion of the plurality of mesopores of the hydrogen storage material.

[0206] Embodiment 134. The method of embodiment 133, wherein the hydrogen gas is stored in the form of at least one hydrogen hydrate in at least a portion of the plurality of mesopores of the hydrogen storage material. EXAMPLES

[0207] The following examples illustrate some embodiments and aspects of the invention. It will be apparent to those skilled in the relevant art that various modifications, additions, substitutions, and the like can be performed without altering the spirit or scope of the invention, and such modifications and variations are encompassed within the scope of the invention as defined in the claims which follow. The following examples do not in any way limit the invention.

[0208] Experimental Methods

[0209] Materials.

[0210] Analytical grade hydrogen (99.9%) was supplied from Matheson industrial gas supplier, deionized water from fisher chemical (W5), THF with a purity of 99.9% from Sigma- Aldrich (1002717184), zeolite Y from Zeolyst (CBV720, Si / Al ratio of 15), zeolite 13X from ACS materials (MSZ13015, Si / Al ratio of 5) with pore size of 1.9 nm, zeolite 13X from Sigma-Aldrich (1003320272, Si / Al ratio of 1.23) with measured pore size of 2.1 nm, zeolite 4a from Thermoscientific (L05466.30) with measured pore size of 4.73 nm, zeolite 4a with Sorbent Media with measured pore size of 10.9 nm, and porous carbon from ACS Material (CNP00001). To render a uniform distribution of mesopores in zeolite Y (sample Z3), we used a protocol established by Garcia-Martinez and coworkers ( García-Martínez, J., Johnson, M., Valla, J., Li, K. & Ying, J. Y. Mesostructured zeolite y - High hydrothermal stability and superior FCC catalytic performance. Catal Sci Technol 2, 987–994 (2012)). This technique utilizes a surfactant-assisted post-synthesis treatment of FAU-type zeolites that proceeded without disruption of the chemical or physical4865-9272-1067.1Page 37 of 49094876-000007WOPTproperties of the zeolite. The proposed mechanism involves a crystal rearrangement process upon the formation of micelles that promote the restructuring of the zeolite framework, as reported in the literature (See García-Martínez, J., Johnson, M., Valla, J., Li, K. & Ying, J. Y. Mesostructured zeolite y - High hydrothermal stability and superior FCC catalytic performance. Catal Sci Technol 2, 987–994 (2012)).

[0211] Hydrogen solubility in various pore sizes.

[0212] An experimental procedure was conducted to examine hydrogen solubility in a representative zeolite sample (zeolite 13X) with varying pores diameters, activated carbon, activated Al2O3, and nano powder SiO2. We initially measured pore size distribution in these different materials using BET analysis of N2adsorption / desorption isotherms, as shown in FIG. 6A – FIG. 6D. Since water molecules are restructured inside the pores, there is an association between pore diameter and hydrogen solubility. It has been shown in FIG. 7A – FIG.7B that the ideal pore size for maximum hydrogen solubility is between 2 to 3 nm. At these dimensions, water molecules form ordered ice-like structures within the pores causing confinement of gas molecules in the regions of low water density and leading to an approximate 2-fold enhancement of hydrogen solubility in the water structure. Even though gas solubility enhancement is observed in pores a few nm in size, the solubility in 1 nm pores is lower because the high curvature of the pore surface prevents water from ordering. Also, the solubility in pores larger than 6 nm is almost similar to bulk liquid water.

[0213] Physics of hydrogen hydrate nucleation.

[0214] Hydrates are ice-like crystalline compounds that can form at temperatures higher than the water-ice phase transition temperature. Nucleation rate according to the classical nucleation theory is written as: ^^ ൌ ^^^^^ିכ ^^ οீ^ (Equation 1)where K is the kinetic constant, ^^is the Boltzmann constant and T is the system temperature. ο^כis the Gibbs energy barrier for heterogeneous nucleation, which is given by (Fletcher, N. H. Size Effect in Heterogeneous Nucleation. J Chem Phys 29, 572 (1958).4865-9272-1067.1Page 38 of 49094876-000007WOPT^^^గ^య ο^כൌఊಹೈଷ^οீೇమ^^^^ǡ ^^ (Equation 2) where ^ு^^is thewater (i.e. hydrogen hydrate-water), ο^^^is the volumetric free energy of phase-change, and ^^^ǡ^^ is the surface function. The parameter^ depends on the surface energy of the interfaces (^ ൌ ^^^^ ൌ ^^ௌ^െ ^ௌு^Ȁ^ு^), where ^ௌ^denotes solid-water interfacial energy, ^ௌுdenotes solid-hydrates interfacial energy, and ^ு^denotes water-hydrate interfacial energy. The term ^ denotes the ratio of the nucleating surface radius (R) to the critical nucleolus radius (^^). The ^^^ǡ ^^ functional form for concave pore surfaces is given by: ^ା^௫ ଷ ଷ ^^^ǡ ^^ ൌ^^^ െ ^ ^ െ ^ଷ^^ା௫^ା௫ଶ ௫ା^ଶ^^ʹ െ ͵^^^^ ^ ^^^^ ൨ ^ ͵^^ ^^^െ ^^^ (Equation 3)ൌଶThe^ ^^ǡ ^^ function varies between 0 and 1, in which ^^^ǡ ^^ equal to 1 represents the homogenous nucleation limit (i.e. no involved surfaces) and ^^^ǡ ^^ equal to 0 corresponds to nucleation with no sub-cooling ( Hakimian, A., Nazifi, S. & Ghasemi, H. Physics of Ice Nucleation and Growth on a Surface. Ice Adhesion 87–110 (2020)). We plotted ^^^ǡ ^^ for concave surfaces in FIG.1C for different values of m. For the range −1≤ ^ < 1, when ^ is smaller than 1, the curvature of the pore surface can affect the ^^^ǡ ^^ function. That is, the mean radius of surface curvature should be less than the critical nucleus radius (x < 1). For x > 1, ^^^ǡ ^^ is independent of surface roughness, which is in agreement with results of Eberle et al. (Eberle, P., Tiwari, M. K., Maitra, T. & Poulikakos, D. Rational nanostructuring of surfaces for extraordinary icephobicity. Nanoscale 6, 4874–81 (2014) where ^^^ǡ ^^ approaches zero as the pore radius of curvature approaches zero. This suggests a drastic drop in the free energy barrier for nucleation based on equation (2), and therefore a higher nucleation rate.

[0215] Surface energy of the interfaces.

[0216] The exact calculation of ^ is difficult as we do not have accurate information on the interfacial energies. During the hydration process for Z3 material, a hydrated layer of water4865-9272-1067.1Page 39 of 49094876-000007WOPTforms on the surface of the pores and nucleated hydrate interacts with the hydrated layer. Due to substantial number of hydrophilic Si-OH groups present on the surface of Z3 mesopores, we posit an ice-like structure of water at this interface. Ice and hydrogen hydrates have closely similar structures. As the interface of water-Z3 resembles a water-ice interface, once water transforms to hydrate nucleus, we expect the ^ௌுapproaches zero and consequently the m value approaches 1. We again emphasize that this is an approximate value that does not alter the conclusions of this work. As shown in FIG.1C, for all ^ values, the role of the radius of curvature is significant. We determined the critical nucleus radius (^^) of hydrogen hydrate, which is written as ^^ൌଶ^ఊಹೈ^οீೡ^ (Equation 5) The critical nucleus is 6.82 nm at= 0.0245 Nm-1and ο^௩= 7.17E6 Jm-3); thus, only for the pores with diameters less than 6.82 nm, the Gibbs energy can be tuned significantlythrough pore curvature. For example, for m=0.95 and pores with 3 nm diameter, the x value is 0.22 for which ^^^ǡ ^^ becomes 6.12E-5 (i.e.30 times reduction in Gibbs energy barrier compared to bulk nucleation). Therefore, nanoconfinement can tune the Gibbs energy barrier to small values to increase the rate of hydrate nucleation. A similar conclusion was made by Liang et al. (Liang, H., Möhler, O., Griffiths, S. & Zou, L. Enhanced Ice Nucleation and Growth by Porous Composite of RGO and Hydrophilic Silica Nanoparticles. Journal of Physical Chemistry C (2020)) in which they found pore size and hydrophilicity can enhance the kinetics of ice nucleation by facilitating water molecule collection and subsequently rearranging water into a hexagonal structure on the surface.

[0217] Pore dimension distribution and surface chemistry.

[0218] We conducted a hydrogen storage experiment with mesoporous carbon of 1.8 nm pore diameter, FIG.8A – FIG.8B. We were unable to form hydrogen hydrates within the carbon pores despite carbon having a smaller pore dimension comparable to Z3 and much smaller than zeolite 13x with a pore diameter of 10 nm. The advantage of zeolites compared to carbon is the specific surface chemistry. FTIR spectroscopy of water filled mesoporous carbon is shown in FIG. 8A – FIG. 8B. The ratio of DDAA to DA bonds in carbon structures is 1.10 while this value is 0.94 for bulk water. As discussed later, this ratio is much higher for zeolite structures due to the4865-9272-1067.1Page 40 of 49094876-000007WOPThigh density of Si-OH groups in mesoporous zeolites. That is, surface chemistry plays a critical role in hydrate formation.

[0219] The pore size distribution and nature of water bonds in zeolite 13X with 4 nm pores is shown in FIG. 9A – FIG. 9B; and the ratio of DDAA to DA bonds is 1.25. The pore size distribution and nature of water bonds in zeolite 13X with 10 nm pores is shown in FIG.10A – FIG.10B; and the ratio of DDAA to DA bonds is 1.21.

[0220] Experimental setup for hydrogen storage.

[0221] The closed system is defined as ^ଶ^ / THF / ^ଶmixture and the porous material platform. The schematic of the experimental setup and pictures of the actual setup are shown in FIG. 11A – FIG. 11C. The experiments were conducted in a cylindrical stainless-steel chamber with an inner diameter of 6 cm and an internal volume of 300 mL. The chamber has six ports at the top, as shown in FIG.11A – FIG.11C, where were used for ^ଶinjection, safety valve, vacuum pump, pressure transducer, thermocouple, and exit valve. A Polyscience cooling system was used to maintain the experimental chamber at the specific temperature, which was measured by a J type Omega thermocouple (0.1 K uncertainty). The pressure was recorded by an ASHCROFT pressure transducer (0.1% uncertainty). A National Instruments data acquisition system was used to record the temperature and pressure of the chamber with 0.02 s interval.

[0222] Experimental procedure for hydrogen storage.

[0223] The required concentration of water / THF solution (10 mol% THF) was prepared by adding a known quantity of THF in deionized (DI) water. In order to maintain homogeneity of the prepared solution, it was mixed using a magnetic stirrer for approximately 5 min. For the case of hydrate formation with a material platform, we injected a specific quantity of water / THF solution (10 mol% THF) into the pores of Z3 in proportion to the total volume of its pores. Once it became completely wet, we placed the sample inside the chamber and connected it to the circulating cooling jacket. The vacuum pump was then turned on to achieve almost vacuum condition (~50 Pa) inside the chamber. In order to ensure elimination of any air bubbles in the chamber, it was pressurized with ^ଶ^ gas to approximately 0.5 MPa and depressurized to atmospheric pressure three times. The cooling temperature was then set at 263 K and once reaching steady state, ^ଶ^was introduced into the chamber and pressurized to 10 bar. It can be assumed that this was a quasi-isobaric experiment since the pressure dropped during the experiment is less than 1 bar as a result of gas consumption. It should be noted that the same state applies to all other4865-9272-1067.1Page 41 of 49094876-000007WOPTpressures as well. During H2diffusion and the induction time, the system remains isothermal; however, owing to the exothermicity of hydrogen hydrate formation, the temperature of the system rises while the pressure of the system drops. The pressure drops for two reasons: (i) H2consumption to form hydrogen hydrates, and (ii) the temperature decrease leads to pressure drops. To eliminate the effect of temperature on pressure drop, we also conducted a control experiment with an empty chamber (i.e., without water and porous material) to subtract this factor from our calculations. We also used the control experiment to calculate the cooling rate of the chamber, which was then used to calculate the total heat released from hydrate formation. Pressure and temperature of the system were continuously recorded until no further changes were observed and the system stabilized. After completion of ^ଶ^formation, dissociation of hydrogen hydrate was done by increasing the temperature of the system to room temperature, and the release rate of the stored ^ଶwas measured by recording the pressure changes inside the chamber during dissociation. The ^ଶ^release process was completed when no further pressure change was observed inside the chamber. The raw data for Z3 at pressures of 6, 8, and 10 bar are shown in FIG.12A – FIG.12D; FIG.13A – FIG.13D; and FIG.14A – FIG.14D. The raw data for zeolite 13X with 4 nm pores at pressures of 6, 8, and 10 bar are shown in FIG.15A – FIG.15D; FIG.16A – FIG.16D; and FIG. 17A – FIG.17D. The raw data for zeolite 13X with 10 nm pores at pressures of 12 and 10 bar are shown in FIG.18A – FIG.18D; and FIG.19A – FIG.19B. We emphasize that we could not form hydrogen hydrates in zeolite 13X with 10 nm and 10 bar (or other lower pressures). In addition, the raw data for mesoporous carbon at 11 bar (FIG.20A – FIG.20B) indicate no hydrogen hydrate formation.

[0224] Hydrogen storage capacity.

[0225] The nucleation / growth of hydrate is realized by a sharp jump in the temperature of the system due to the exothermic nature of hydrate formation. FIG.2B shows the time-dependence of temperature in the system. Here, as a conservative estimate, we assumed adiabatic condition for the system during hydrate nucleation and growth; thus, all the thermal energy released in the hydrate formation process is converted into sensible heat of the system. By integration of the temperature-time curve (Table 1), we could determine the total change in sensible heat of the system. Having this change and the enthalpy of hydrate formation, we determined the mass of hydrogen hydrate formed in the material platform.4865-9272-1067.1Page 42 of 49094876-000007WOPT

[0226] The various methods and techniques described above provide a number of ways to carry out the application. Of course, it is to be understood that not necessarily all objectives or advantages described can be achieved in accordance with any particular embodiment described herein. Thus, for example, those skilled in the art will recognize that the methods can be performed in a manner that achieves or optimizes one advantage or group of advantages as taught herein without necessarily achieving other objectives or advantages as taught or suggested herein. A variety of alternatives are mentioned herein. It is to be understood that some preferred embodiments specifically include one, another, or several features, while others specifically exclude one, another, or several features, while still others mitigate a particular feature by inclusion of one, another, or several advantageous features.

[0227] Furthermore, the skilled artisan will recognize the applicability of various features from different embodiments. Similarly, the various elements, features and steps discussed above, as well as other known equivalents for each such element, feature, or step, can be employed in various combinations by one of ordinary skill in this art to perform methods in accordance with the principles described herein. Among the various elements, features, and steps some will be specifically included and others specifically excluded in diverse embodiments.

[0228] Although the application has been disclosed in the context of certain embodiments and examples, it will be understood by those skilled in the art that the embodiments of the application extend beyond the specifically disclosed embodiments to other alternative embodiments and / or uses and modifications and equivalents thereof.

[0229] Preferred embodiments of this application are described herein, including the best mode known to the inventors for carrying out the application. Variations on those preferred embodiments will become apparent to those of ordinary skill in the art upon reading the foregoing description. It is contemplated that skilled artisans can employ such variations as appropriate, and the application can be practiced otherwise than specifically described herein. Accordingly, many embodiments of this application include all modifications and equivalents of the subject matter recited in the claims appended hereto as permitted by applicable law. Moreover, any combination of the above-described elements in all possible variations thereof is encompassed by the application unless otherwise indicated herein or otherwise clearly contradicted by context.

[0230] All patents, patent applications, publications of patent applications, and other material, such as articles, books, specifications, publications, documents, things, and / or the like,4865-9272-1067.1Page 43 of 49094876-000007WOPTreferenced herein are hereby incorporated herein by this reference in their entirety for all purposes, excepting any prosecution file history associated with same, any of same that is inconsistent with or in conflict with the present document, or any of same that may have a limiting affect as to the broadest scope of the claims now or later associated with the present document. By way of example, should there be any inconsistency or conflict between the description, definition, and / or the use of a term associated with any of the incorporated material and that associated with the present document, the description, definition, and / or the use of the term in the present document shall prevail.

[0231] It is to be understood that the embodiments of the application disclosed herein are illustrative of the principles of the embodiments of the application. Other modifications that can be employed can be within the scope of the application. Thus, by way of example, but not of limitation, alternative configurations of the embodiments of the application can be utilized in accordance with the teachings herein. Accordingly, embodiments of the present application are not limited to that precisely as shown and described.

[0232] Various embodiments of the invention are described above in the Detailed Description. While these descriptions directly describe the above embodiments, it is understood that those skilled in the art may conceive modifications and / or variations to the specific embodiments shown and described herein. Any such modifications or variations that fall within the purview of this description are intended to be included therein as well. Unless specifically noted, it is the intention of the inventors that the words and phrases in the specification and claims be given the ordinary and accustomed meanings to those of ordinary skill in the applicable art(s).

[0233] The foregoing description of various embodiments of the invention known to the applicant at this time of filing the application has been presented and is intended for the purposes of illustration and description. The present description is not intended to be exhaustive nor limit the invention to the precise form disclosed and many modifications and variations are possible in the light of the above teachings. The embodiments described serve to explain the principles of the invention and its practical application and to enable others skilled in the art to utilize the invention in various embodiments and with various modifications as are suited to the particular use contemplated. Therefore, it is intended that the invention is not limited to the particular embodiments disclosed for carrying out the invention.4865-9272-1067.1Page 44 of 49094876-000007WOPT

[0234] While particular embodiments of the present invention have been shown and described, it will be obvious to those skilled in the art that, based upon the teachings herein, changes and modifications may be made without departing from this invention and its broader aspects and, therefore, the appended claims are to encompass within their scope all such changes and modifications as are within the true spirit and scope of this invention.4865-9272-1067.1Page 45 of 49094876-000007WOPT

Claims

CLAIMS What is claimed is:

1. A hydrogen storage material, the hydrogen storage material comprising: a mesoporous zeolite, wherein the mesoporous zeolite comprises a plurality of mesopores.

2. The hydrogen storage material of claim 1, wherein the mesoporous zeolite is a modified zeolite Y.

3. The hydrogen storage material of claim 1, wherein the plurality of mesopores have a pore size of 1.0 nm to 50.0 nm.

4. The hydrogen storage material of claim 3, wherein the pore size is 2.0 nm to 3.0 nm, or wherein the pore size is 2.4 nm.

5. The hydrogen storage material of claim 1, wherein the mesoporous zeolite comprises a surface area of 1100 m2g-1.

6. The hydrogen storage material of claim 1, wherein the mesoporous zeolite is a powder.

7. The hydrogen storage material of claim 1, wherein the mesoporous zeolite comprises at least one concave surface.

8. The hydrogen storage material of claim 1, wherein the mesoporous zeolite comprises an aluminosilicate framework, or wherein the mesoporous zeolite comprises a FAU crystal structure.

9. The hydrogen storage material of claim 1, wherein the mesoporous zeolite comprises a hydrogen storage capacity of about 1.23 wt% to about 2.1 wt% based on the total weight of the mesoporous zeolite at a pressure of about 6 bar to about 10 bar.4865-9272-1067.1Page 46 of 49094876-000007WOPT10. The hydrogen storage material of claim 1, wherein the mesoporous zeolite has a hydrogen charging time of 0.16 hours at a pressure of 10 bar, or wherein the mesoporous zeolite has a hydrogen discharging time of 1.42 hours at a temperature of 273 K.

11. A hydrogen storage system, comprising: an inlet port; a reaction chamber, wherein the reaction chamber is in communication with the inlet port, and wherein the reaction chamber contains a hydrogen storage material of claim 1; and an outlet port, wherein the outlet port is in communication with the reaction chamber.

12. The hydrogen storage system of claim 11, wherein the reaction chamber further contains water, or at least one promoter, or both water and at least one promoter.

13. The hydrogen storage system of claim 12, wherein the at least one promoter is tetrahydrofuran (THF) or tetrahydrothiophene (THT).

14. A method for storing hydrogen, the method comprising: providing a hydrogen storage material of claim 1; providing water, or at least one promoter, or both water and at least one promoter; contacting the hydrogen storage material with the water, the at least one promoter, or both; filling at least a portion of the plurality of mesopores of the hydrogen storage material with the water, the at least one promoter, or both to provide an activated hydrogen storage material; and contacting the activated hydrogen storage material with hydrogen gas under conditions suitable for storing hydrogen in at least a portion of the plurality of mesopores of the hydrogen storage material.4865-9272-1067.1Page 47 of 49094876-000007WOPT15. The method of claim 14, wherein the hydrogen gas is stored in the form of at least one hydrogen hydrate in at least a portion of the plurality of mesopores of the hydrogen storage material.4865-9272-1067.1Page 48 of 49094876-000007WOPT

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