WO2019083694A1 - Methods of forming hydrogen clusters - Google Patents

Abstract

A method includes inducing interstitial stress within a lattice structure of a crystalline metallic material in a closed environment to generate a plurality of defects and dislocations in the lattice structure. The method further includes cycling one or more isotopes of hydrogen within the closed environment between a gaseous phase and a hydride phase by varying temperature while maintaining constant pressure to form clusters within the plurality of defects and dislocations generated in the lattice structure, each cluster including multiple atoms of the one or more isotopes of hydrogen.

Description

METHODS OF FORMING HYDROGEN CLUSTERS

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] The present application claims priority to and benefit from U.S. Provisional Patent Application Serial No. 62/577,360 titled "Methods for Forming Hydrogen

Clusters", filed on October 26, 2017, the content of which is incorporated by reference herein.

TECHNICAL FIELD

[0002] The present invention relates to defect / dislocation site formation techniques, and more particularly to formation of gas clusters in defect / dislocation areas within metal based substances.

BACKGROUND

[0003] A gas-loaded heat generator is capable of producing thermal energy by interaction between one or more isotopes of hydrogen and a crystalline metallic material with affinity to hydrogen. The crystalline metallic material be a base for reversible reactions of absorption and desorption. Most metallic materials that reversibly react with gaseous hydrogen and/or its isotopes represent alloys or intermetallic compounds, usually in a combination of metals with higher hydrogen affinity and with non-hydrogen affinity.

[0004] The material could be pulverized or filmed to maximize gas contact due to its increased surface area to improve the efficiency of the gas-loaded heat generator.

However, in most instances, the metallic material nonetheless absorbs and desorbs gaseous hydrogen and/or its isotopes into its lattice as a single atom to form a chemically stable beta phase hydride or deuteride. Forming dislocations /defects in metallic micro- structure materials may increase gas contact thereby improving efficiency of the gas- loaded heat generation; however, standard techniques provide a relatively low density of such dislocations /defects sites, which hampers the ability to prepare commercially viable gas-loaded heat generation devices. Thus, there is an ongoing need for further advancements in this area of technology.

SUMMARY

[0005] The following presents a simplified summary of the disclosure in order to provide a basic understanding to those of skill in the art. This summary is not an extensive overview of the disclosure and is not intended to identify key/critical elements of embodiments of the invention or to delineate the scope of the invention. The sole purpose of this summary is to present some concepts disclosed herein.

[0006] According to one embodiment, a method comprises inducing interstitial stress within a lattice structure of a crystalline metallic material in a closed environment to generate a plurality of defects and dislocations in the lattice structure, and cycling one or more isotopes of hydrogen within the closed environment between a gaseous phase and one or more of a hydride phase and a solid solution phase by varying temperature while maintaining constant pressure to form clusters within the plurality of defects and dislocations generated in the lattice structure, each cluster including multiple atoms of the one or more isotopes of hydrogen. [0007] In one or more embodiments, the pressure is set at a predefined value at which an inter-phase equilibrium between a solid solution a phase and a hydride β phase occurs for the one or more isotopes of hydrogen.

[0008] In one or more embodiments, the temperature is varied on either side of a critical temperature T_c at which an inter-phase equilibrium between a solid solution a phase and a hydride β phase occurs for the one or more isotopes of hydrogen.

[0009] In one or more embodiments, the varying temperature while maintaining constant pressure induces the interstitial stress within the lattices structure of the crystalline metallic structure.

[0010] In one or more embodiments, the method further comprises loading and deloading of the one or more isotopes of hydrogen within the lattice structure of the crystalline metallic material.

[0011] In one or more embodiments, the cycling the one or more isotopes of hydrogen within the closed environment between a gaseous phase and a hydride phase comprises phase change of the one or more isotopes of hydrogen between a solid solution a phase and a metal hydride β phase.

[0012] In one or more embodiments, the forming the clusters of the one or more isotopes of hydrogen comprises trapping the one or more isotopes of hydrogen within the plurality of defects and dislocations generated in the lattice structure.

[0013] In one or more embodiments, the cycling the one or more isotopes of hydrogen within the closed environment between the gaseous phase and the hydride phase comprises switching between a hydrogen absorption process and a hydrogen desorption process.

[0014] In one or more embodiments, the cycling the one or more isotopes of hydrogen within the closed environment between a gaseous phase and a hydride phase comprises switching between an exothermic reaction associated with a solid solution a phase and an endothermic reaction associated with the hydride β phase.

[0015] In one or more embodiments, the crystalline metallic material comprises nanoscale particles.

[0016] In one or more embodiments, a population of the one or more isotopes of hydrogen in a hydride β phase is reduced and a population of the one or more isotopes of hydrogen in a solid solution a phase is increased when the temperature is increased.

[0017] In one or more embodiments, a population of the one or more isotopes of hydrogen in a hydride β phase is increased and a population of the one or more isotopes of hydrogen in a solid solution a phase is decreased when temperature is decreased.

[0018] In one or more embodiments, the method further comprises thermally insulating the closed environment.

[0019] According to another embodiment, the method comprises inducing interstitial stress within a lattice structure of a crystalline metallic material in a closed environment to generate a plurality of defects and dislocations in the lattice structure; cycling one or more isotopes of hydrogen within the closed environment between a gaseous phase and one or more of a hydride phase and a solid solution phase by varying pressure while maintaining constant temperature to form clusters within the plurality of defects and dislocations generated in the lattice structure, each cluster including multiple atoms of the one or more isotopes of hydrogen.

[0020] In one or more embodiments, the temperature is set at a predefined value at which an inter-phase equilibrium between a solid solution a phase and a hydride β phase occurs for the one or more isotopes of hydrogen.

[0021] In one or more embodiments, the temperature is varied on either side of a predefined pressure P_c at which an inter-phase equilibrium between a solid solution a phase and a hydride β phase occurs for the one or more isotopes of hydrogen.

[0022] In one or more embodiments, the varying pressure while maintaining constant temperature induces the interstitial stress within the lattices structure of the crystalline metallic structure.

[0023] In one or more embodiments, the method further comprises loading and deloading of the one or more isotopes of hydrogen within the lattice structure of the crystalline metallic material.

[0024] In one or more embodiments, the cycling the one or more isotopes of hydrogen within the closed environment between a gaseous phase and a hydride phase comprises phase change of the one or more isotopes of hydrogen between a solid solution a phase and a metal hydride β phase. [0025] In one or more embodiments, forming the clusters of the one or more isotopes of hydrogen comprises trapping the one or more isotopes of hydrogen within the plurality of defects and dislocations generated in the lattice structure.

[0026] In one or more embodiments, the cycling the one or more isotopes of hydrogen within the closed environment between the gaseous phase and the hydride phase comprises switching between a hydrogen absorption process and a hydrogen desorption process.

[0027] In one or more embodiments, the cycling the one or more isotopes of hydrogen within the closed environment between a gaseous phase and a hydride phase comprises switching between an exothermic reaction associated with a solid solution a phase and an endothermic reaction associated with the hydride β phase.

[0028] In one or more embodiments, the crystalline metallic material comprises nanoscale particles.

[0029] In one or more embodiments, a population of the one or more isotopes of hydrogen in a hydride β phase is increased and a population of the one or more isotopes of hydrogen in a solid solution a phase is decreased when the pressure is increased.

[0030] In one or more embodiments, a population of the one or more isotopes of hydrogen in a hydride β phase is decreased and a population of the one or more isotopes of hydrogen in a solid solution a phase is increased when pressure is decreased.

[0031] In one or more embodiments, the method further comprises thermally insulating the closed environment. [0032] In a further embodiment, the method comprises inducing interstitial stress within a lattice structure of a crystalline metallic material in a closed environment to generate a plurality of defects and dislocations in the lattice structure, and cycling one or more isotopes of hydrogen within the closed environment between a gaseous phase and one or more of a hydride phase and a solid solution phase by varying temperature and pressure to form clusters within the plurality of defects and dislocations generated in the lattice structure, each cluster including multiple atoms of the one or more isotopes of hydrogen.

[0033] In one or more embodiments, the temperature is varied on either side of a critical temperature T_c and on either side of a predefined pressure P_c at which an interphase equilibrium between a solid solution a phase and a hydride β phase occurs for the one or more isotopes of hydrogen.

[0034] In one or more embodiments, the varying the temperature and the pressure induces the interstitial stress within the lattices structure of the crystalline metallic structure.

[0035] In one or more embodiments, the method further comprises loading and deloading of the one or more isotopes of hydrogen within the lattice structure of the crystalline metallic material.

[0036] In one or more embodiments, the cycling the one or more isotopes of hydrogen within the closed environment between a gaseous phase and a hydride phase comprises phase change of the one or more isotopes of hydrogen between a solid solution a phase and a metal hydride β phase. [0037] In one or more embodiments, forming the clusters of the one or more isotopes of hydrogen comprises trapping the one or more isotopes of hydrogen within the plurality of defects and dislocations generated in the lattice structure.

[0038] In one or more embodiments, the cycling the one or more isotopes of hydrogen within the closed environment between the gaseous phase and the hydride phase comprises switching between a hydrogen absorption process and a hydrogen desorption process.

[0039] In one or more embodiments, the cycling the one or more isotopes of hydrogen within the closed environment between a gaseous phase and a hydride phase comprises switching between an exothermic reaction associated with a solid solution a phase and an endothermic reaction associated with the hydride β phase.

[0040] In one or more embodiments, the crystalline metallic material comprises nanoscale particles.

[0041] In one or more embodiments, a population of the one or more isotopes of hydrogen in a hydride β phase is reduced and a population of the one or more isotopes of hydrogen in a solid solution a phase is increased when the temperature is increased.

[0042] In one or more embodiments, a population of the one or more isotopes of hydrogen in a hydride β phase is increased and a population of the one or more isotopes of hydrogen in a solid solution a phase is decreased when temperature is decreased. [0043] In one or more embodiments, a population of the one or more isotopes of hydrogen in a hydride β phase is increased and a population of the one or more isotopes of hydrogen in a solid solution a phase is decreased when the pressure is increased.

[0044] In one or more embodiments, a population of the one or more isotopes of hydrogen in a hydride β phase is decreased and a population of the one or more isotopes of hydrogen in a solid solution a phase is increased when pressure is decreased.

[0045] In one or more embodiments, the method further comprises thermally insulating the closed environment.

BRIEF DESCRIPTION OF THE DRAWINGS

[0046] The present invention will now be described more fully hereinafter with reference to the accompanying drawings, in which embodiments of the invention are shown. However, this invention should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art. Like numbers refer to like elements throughout.

[0047] FIG. 1 is a partial schematic view of a multilayer thin film structure.

[0048] FIG. 2 is a schematic view of a dislocation core formed in a lattice of the device of FIG. 1.

[0049] FIG. 3 is a schematic partial view of an interface between layers of the FIG. 1 device along which dislocation cores have been formed. [0050] FIG. 4 shows a graph displaying a pressure-composition isotherm

corresponding to isotopes of hydrogen in a solid solution a phase and a hydride β in a crystalline metallic material; FIG. 4 further displays a van't Hoff diagram.

[0051] FIG. 5 shows a graph displaying pressure concentration isotherms

corresponding to a change in a population of hydrogen in a solid solution a phase and in a hydride β in the crystalline metallic material when a closed environment is cycled between absorption and desorption processes.

[0052] FIG. 6 is a graph displaying pressure concentration isotherms corresponding to a change in the population of hydrogen in the solid solution a phase and in the hydride β in the crystalline metallic material when a closed environment is cycled between absorption and desorption processes while varying temperature under isobar conditions.

[0053] FIG. 7 is a graph displaying temperature concentration isobars corresponding to a change in isotopes of hydrogen in a solid solution a phase and in a hydride β in the crystalline metallic material when a closed environment is cycled between absorption and desorption processes while varying pressure under isotherm conditions.

[0054] FIG. 8 represents a set of graphs displaying pressure concentration isotherms corresponding to a change in isotopes of hydrogen in a solid solution a phase and in a hydride β in the crystalline metallic material when a closed environment is cycled between absorption and desorption processes while varying temperature and pressure.

[0055] FIG. 9 represents another set of graphs displaying pressure concentration isotherms corresponding to a change in isotopes of hydrogen in a solid solution a phase and in a hydride β in the crystalline metallic material when a closed environment is cycled between absorption and desorption processes while varying temperature and pressure.

DETAILED DESCRIPTION

[0056] These descriptions are presented with sufficient details to provide an understanding of one or more particular embodiments of broader inventive subject matters. These descriptions expound upon and exemplify particular features of those particular embodiments without limiting the inventive subject matters to the explicitly described embodiments and features. Considerations in view of these descriptions will likely give rise to additional and similar embodiments and features without departing from the scope of the inventive subject matters. Although the term "step" may be expressly used or implied relating to features of processes or methods, no implication is made of any particular order or sequence among such expressed or implied steps unless an order or sequence is explicitly stated.

[0057] Any dimensions expressed or implied in the drawings and these descriptions are provided for exemplary purposes. Thus, not all embodiments within the scope of the drawings and these descriptions are made according to such exemplary dimensions. The drawings are not made necessarily to scale. Thus, not all embodiments within the scope of the drawings and these descriptions are made according to the apparent scale of the drawings with regard to relative dimensions in the drawings. However, for each drawing, at least one embodiment is made according to the apparent relative scale of the drawing.

[0058] Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood to one of ordinary skill in the art to which the presently disclosed subject matter pertains. Although any methods, devices, and materials similar or equivalent to those described herein can be used in the practice or testing of the presently disclosed subject matter, representative methods, devices, and materials are now described.

[0059] Following long-standing patent law convention, the terms "a", "an", and "the" refer to "one or more" when used in the subject specification, including the claims. Thus, for example, reference to "a device" can include a plurality of such devices, and so forth.

[0060] Unless otherwise indicated, all numbers expressing quantities of components, conditions, and so forth used in the specification and claims are to be understood as being modified in all instances by the term "about". Accordingly, unless indicated to the contrary, the numerical parameters set forth in the instant specification and attached claims are approximations that can vary depending upon the desired properties sought to be obtained by the presently disclosed subject matter.

[0061] As used herein, when referring to a value or to an amount of mass, weight, time, volume, concentration, and/or percentage it can encompass variations of, in some embodiments +/-20%, in some embodiments +/- 10%, in some embodiments +1-5%, in some embodiments +/-1%, in some embodiments +/-0.5%, and in some embodiments +/- 0.1%, from the specified amount, as such variations are appropriate in the presently disclosed subject matter.

[0062] For the purposes of promoting an understanding of the principles of the invention, reference will now be made to the embodiments illustrated in the drawings and specific language will be used to describe the same. It will nevertheless be understood that no limitation of the scope of the invention is thereby intended. Any alterations and further modifications in the described embodiments, and any further applications of the principles of the invention as described herein are contemplated as would normally occur to one skilled in the art to which the invention relates.

[0063] The embodiments of the instant invention are directed to methods for an improved hydrogenation process of crystalline metallic material. The invention advantageously results in clusters of hydrogen atoms, rather than single hydrogen atoms, being attached to defects and deformations present in the lattice structure of the crystalline metallic material. The invention further advantageously results in the formation of new dislocations and defects in the crystalline material where new clusters could be formed. The invention furthermore advantageously results in the increase in the size of each cluster formed in such dislocations and defects.

[0064] In one embodiment, new dislocation and defects are formed within the lattice structure, and clusters of increased size are formed in the newly formed dislocation and defects by inducing interstitial stress within a lattice structure of a crystalline metallic material in a closed environment to generate a plurality of defects and dislocations in the lattice structure. Further, one or more isotopes of hydrogen within the closed environment are cycled between a gaseous phase and a hydride phase by varying temperature while maintaining constant pressure to form clusters within the plurality of defects and dislocations generated in the lattice structure, each cluster including multiple atoms of the one or more isotopes of hydrogen. [0065] The process as explained herein advantageously increases the probability and concentration of atoms of one or more isotopes of hydrogen being trapped into vacancies, defects and dislocations present in the lattice structure of the crystalline metallic material, thereby maximizing the overall quantity of hydrogen and/or its isotopes absorption by the crystalline metallic material bulk.

[0066] The "one or more isotopes of hydrogen" may interchangeably be also referred to herein as just "hydrogen". Further, as used herein, a vacancy is defined a type of point defect in a crystal.

[0067] Crystalline solids exhibit a periodic crystal structure. The positions of atoms or molecules occur on repeating fixed distances, determined by the unit cell parameters. However, the arrangement of atoms or molecules in most crystalline materials is not perfect. The regular patterns are interrupted by crystallographic defects. Crystals inherently possess imperfections, sometimes referred to as crystalline defects. A defect in which an atom is missing from one of the lattice sites is often referred to as a "vacancy" defect. Vacancies occur naturally in all crystalline materials. Vacancies are formed during solidification due to vibration of atoms, local rearrangement of atoms, plastic deformation and ionic bombardments. The creation of a vacancy can result from supplying energy required to break the bonds between an atom inside the crystal and its nearest neighbor atoms. Once that atom is removed from the lattice site, it is put back on the surface of the crystal and some energy is retrieved because new bonds are established with other atoms on the surface. However, there is a net input of energy resulting from a vacancy formation because there are fewer bonds between surface atoms than between atoms in the interior of the crystal. [0068] Point defect in a crystal is where an atom is missing or is in an irregular place in the lattice structure. Point defects include self-interstitial atoms, interstitial impurity atoms, substitutional atoms and vacancies. Dislocations in a crystal are areas were the atoms are out of position in the crystal structure. Dislocations are generated and move when a stress is applied.

[0069] As used herein, the term "hydride" refers to anions of all isotopes of hydrogen. The processes as described herein advantageously result in improved efficiency of thermal energy production by a gas-loaded heat generator relying on a gas such as hydrogen for thermal energy production. As used herein, the term "solid solution phase" refers to the phase where hydrogen forms an integral part of the lattice structure of the crystalline metallic material; the term "solid solution phase" also refers to the a phase hydrogen atoms. Hydrogen may exhibit two phases - an a phase and a β phase - in an equilibrium condition. For example, the left side graph of FIG. 4 shows a phase diagram of hydrogen showing two phases of hydrogen, i.e., the solid solution a phase and the hydride β phase formed over a range of plateau pressure for three different temperatures Ti, T₂ and T₃. A phase is defined as a homogenous portion of a system that has uniform physical and chemical characteristics, i.e., it is a physically distinct from other phases, chemically homogenous and mechanically separable portion of a system. A diagram that depicts existence of different phases of a system under equilibrium is termed as phase diagram. Phase diagrams are helpful in predicting phase transformations and the resulting microstructures, which may have equilibrium or non-equilibrium character. A phase diagram may be classified based on the number of components in the system, and a binary phase diagram is a map that represents the relationships between temperature and the compositions and quantities of phases at equilibrium, which influence the microstructure of an alloy. Many microstructures develop from phase transformations, the changes occurring when the temperature is altered. This may involve the transition from one phase to another, or the appearance or disappearance of a phase. A binary equilibrium phase diagram, such as those illustrated in each of FIGS. 5-9, for example, represents the relationships between temperature and the compositions and the quantities of phases of a system under equilibrium. Thus, each of FIGS. 5-9 illustrates how the quantities of hydrogen in each of the two phases - the solid solution a phase and the hydride β phase - changes depending on changes in temperature and / or pressure that a closed system containing both the microstructure and the hydrogen is subjected to.

[0070] A cluster of hydrogen atoms may form in the lattice structure of a crystalline metallic material during a normal absorption reaction when the crystalline metallic material is in the process of absorbing hydrogen. A cluster of hydrogen may also form during the normal desorption reaction that occurs when the reaction conditions are reversed. Since the absorption of hydrogen is a reversible reaction, by reversing the process conditions, the crystalline material may commence to release the absorbed hydrogen. As the bulk material is cycled repeatedly between an absorption phase and a desorption phase, the interstitial stress caused by the varying conditions results in the formation of new defects and deformations. This leads to the formation of clusters comprising those atoms of the isotopes of hydrogen that transfer repeatedly between a solid solution a phase and a hydride β phase as the closed environment is subjected to temperature and pressure conditions on either side of an inter-phase equilibrium between the a and β phases. The inter-phase equilibrium region is also referred to herein as the "plateau" region. Inter-phase equilibrium as used herein refers to the equilibrium which exists between the two phases / states of hydrogen - the solid solution a phase and the hydride β phase under certain conditions. In general, inter-phase equilibrium is a stage when chemical potential of each component present in the system (i.e., the solid solution a phase and the hydride β phase) stays steady with time. For example, in FIG. 4, the region in center portion of the horizontal axis where α + β phase exists represents this plateau region where the equilibrium between the a and β phases occurs. In other words, the chemical potential of the solid solution a phase hydrogen and the hydride β phase hydrogen stays steady with time within the plateau region.

[0071] Any hydrogen transferring out of a lattice location during the cycling between the absorption and desorption processes may advantageously be attracted to an existing cluster present in a defect / deformation due to the higher bonding energy associated with each cluster, resulting in the increase in size of existing clusters. Further, the interstitial stress caused by the cycling creates new vacancies / defects / deformations, and hydrogen in the ambience surrounding the crystalline metallic material as well as hydrogen transferring out of a lattice location during the cycling may get trapped in newly formed vacancies within the lattice structure; the hydrogen may also trapped in the newly formed defect / deformation locations. This newly trapped / lodged hydrogen in turn will develop into clusters comprising several hydrogen atoms as the system continues to cycle between the absorption and desorption processes.

[0072] Accordingly, by increasing the traffic of hydrogen and/or its isotopes, the number of clusters and the size of each of the clusters can advantageously be increased. In one form, several new stress-created dislocation voids suitable for the formation of such clusters are created at the interfaces between thin films by cyclic loading and deloading of hydrogen while controlling and adjusting the temperature and pressure within the closed environment. In another form, the size of each of these clusters is increased by the cyclic loading and deloading of hydrogen. The density of clusters as well as the size of each cluster is increased by increasing the traffic of hydrogen by changing its state repeatedly between a solid solution a phase and a hydride β phase as the closed environment is subjected to predetermined temperature and pressure conditions by adjusting the temperature and pressure within the closed environment, i.e., by adjusting the temperature and pressure to which the crystalline metallic material and the one or more isotopes of hydrogen are subjected to.

[0073] The process as described herein results in a hydrogenation process of metallic material whereby the hydrogenation occurs not only in the lattice structure of the crystalline metallic material but also in locations of defects and dislocations in the form of clusters with multiple atoms and higher bonding energy. Once the cluster is formed during an absorption reaction, during the desorption reaction when the hydrogen atoms transfer out of lattice, those same atoms forming clusters in the defects and dislocations of the lattice structure nonetheless continue to stay embedded in, and attached to, the cluster because of the higher bonding energy associated with each cluster. Where there is more traffic of hydrogen, there is increased density of clusters and increased size of clusters, and cycling between absorption and desorption process results in increased traffic of hydrogen through the microstructure of the crystalline metallic material. The invention thus advantageously maximizes the probability of the cluster formation using the maximized traffic of hydrogen and/or its isotopes in plateau region with hysteresis where a solid solution a phase and a hydride β phase with increased interstitial stress due frequent phase changes.

[0074] The invention thus maximizes cluster formation and the size of each cluster by maximizing traffic of hydrogen and/or its isotopes in the plateau region with hysteresis where solid solution a phase hydrogen and hydride β phase hydrogen co-exist by generating increased interstitial stress resulting from the frequent phase changes. By generating interstitial stress in the bulk crystalline metallic material, the defect density within the lattice structure of the bulk crystalline metallic material is increased resulting in two advantageous outcomes: (1) forming clusters consisting of multiple atoms within existing defects and dislocations and increasing the size of each of these clusters, and (2) creating new and additional defects and dislocations where new clusters could be formed. This in turn may advantageously result in improved efficiency of thermal energy production by a gas-loaded heat generator relying on a gas such as hydrogen for thermal energy production, the hydrogen being supplied by the crystalline metallic material loaded with hydrogen clusters as described herein.

[0075] Referring now to FIG. 1, as illustrated in FIG. 1, in one embodiment, the crystalline metallic material represents a multilayer thin film device 120. Device 120 includes two multilayer thin film stacks 126 on opposite sides of base/substrate 124. Each stack 126 includes alternating inner layers 128 of different types of metals designated as palladium (Pd) and nickel (Ni), respectively. Between each inner layer 128 of Pd and Ni, a Pd/Ni interface 130 is formed, only a few of which are specifically designated to preserve clarity. In one form, the base 124 is fabricated from stainless steel or aluminum; however, other materials may be used in different embodiments. In one alternative embodiment, the alternating inner layers 128 are of two dissimilar metallic materials. In a further embodiment, the alternating layers 128 are a metal and an oxide of metal, such as alternating inner layers of Pd and PdO. In another embodiment, one layer 128 for each interface 130 is comprised of a material that readily forms a hydride and the other layer 128 for such interface 130 is comprised of material in which isotopes of hydrogen are readily accepted. By way of non-limiting example, Pd and Ti readily form hydrides and Ni readily accepts hydrogen loading. In still another form, one of the alternating inner layers 128 includes one of the group consisting of Pd, Ti, Ni, Li, Au, Ag, U, and alloys thereof, and the other of the alternating inner layers 28 includes a different one of this group. This form is intended to include alternating layers each comprised of a different alloy of Pd, Ti, Ni, Li, Au, Ag, and/or U.

[0076] FIG. 2 illustrates an atomic lattice 140 with a representative dislocation core 142 formed along interface 130 in a portion 144 of two internal layers 128 of device 120 (not to scale). A number of hydrogen atoms comprise cluster 146 in core 142, which may be comprised of one or more hydrogen isotopes - 1H, 2H or D(euterium),and 3H or T(ritium)). In one form, dislocation core 142 is structured to receive a cluster 146 of more than one hydrogen atom or isotope thereof. In another form, dislocation core 142 is structured to receive a cluster 146 of at least 100 hydrogen atoms or isotopes thereof. In an even more preferred form, the dislocation core 142 is structured to receive a cluster 146 of at least 1,000 hydrogen atoms or isotopes thereof.

[0077] As shown in FIG. 3, a number of dislocation cores 142 are shown

schematically along interface 130 formed between inner layer 128 of Pd and inner layer 128 of Ni for device 120. In FIG. 3, the Pd layer is more specifically designated by reference numeral 162 and the Ni layer is more specifically designated by reference numeral 164. It should be understood that the nature of Pd as a more favorable hydride forming substance than Ni likely results in the formation of dislocation cores 142 in layer 162 at interface 130. The dislocation cores 142 contain mismatched atomic structures due to the different materials on each side of the interface 130 - making it susceptible to stress-created dislocations and defects, such that a large density of dislocation sites and defect sites for cluster formation can be obtained with some degree of uniformity along the surface area of interface 130. The use of multiple thin film layers with many interfaces 130 approximates a nearly uniform three-dimensional volume for dislocation and defect formation, and correspondingly for cluster sites to form in those dislocations and defects.

[0078] In one embodiment, formation of device 120 includes providing a first layer of a first type of material and a second layer of a second type of material dissimilar from the first type of material and preparing an interface between the first layer and the second layer to increase a quantity of dislocation sites and defect sites there along in

correspondence with a predefined target. After forming, the device 120 is placed in a closed environment wherein temperature and pressure can be monitored and regulated. In an alternate embodiment, the multilayer thin film device 120 itself may be formed within the closed environment. After placement of the multilayer thin film device 120 within the closed environment, one or more isotopes of hydrogen are supplied into the closed environment to form hydrogen clusters in the dislocation sites and defect sites. The final product that is loaded with increased number of clusters and increased size of each cluster may advantageously be used as a power supply / generation component, or as a charged particle source, or the like.

[0079] Referring now to FIG. 4, the graph on the left side illustrates a pressure- composition isotherm corresponding to isotopes of hydrogen in a solid solution a phase and a hydride β in a metallic structure. The vertical axis (e.g., the y-axis) represents the plateau pressure in bars whereas the horizontal axis (e.g., the x-axis) represents the concentration of hydrogen as a hydrogen to metal ratio (H/M). The thermodynamic aspects of metal hydride formation are illustrated in the pressure-composition isotherms shown in FIG. 4. At small hydrogen to metal ratios (H/M < 0.1) below a certain pressure, one or more isotopes of hydrogen are dissolved in the metal as a solid solution a phase. As the hydrogen concentration increases and pressure rises, the stable metal hydride β phase nucleates and grows. While the two phases co- exist, a plateau at constant pressure is observed, the width of which determines the hydrogen storage capacity of the material. The two-phase region ends at a critical temperature (T_c) beyond which the transition from a to β phase is continuous. Each of the three curves on the left side graph corresponds to a pressure concentration isotherm curve.

[0080] The graph on the right side of FIG. 4 illustrates a van't Hoff diagram. As illustrated on the graph on the right side, the plateau pressure correlates to the change in enthalpy (AH) and entropy (AS) as a function of temperature as represented by the Van't Hoff equation: ln(Peq/Po) = AH/RT - AS/R. In this equation, while enthalpy determines the strength of the metal-hydrogen bond, entropy corresponds to the change from molecular hydrogen to hydrogen in the hydride phase. [0081] In one embodiment, the crystalline metallic material to be loaded with gas represents palladium. Palladium hydride is metallic palladium that contains a substantial quantity of hydrogen within its crystal lattice. Hydrogen absorption by palladium is reversible. Despite its name, it is not an ionic hydride but rather an alloy of palladium with metallic hydrogen that can be written PdHx. At room temperature, palladium hydrides may contain two crystalline phases, a and β (sometimes called α'). Pure a phase exists at x < 0.017 whereas pure β phase is realized for x > 0.58; intermediate x values correspond to α-β mixtures. In FIG. 4, the crystalline structure shown on the left side illustrates how solid solution a phase hydrogen is arranged in the lattice structure of crystalline metallic material. In the same FIG. 4, the crystalline structure shown on the right side illustrates hydride β hydrogen is arranged in the lattice structure of crystalline metallic material.

[0082] Referring now to FIG. 5, the absorption process / reaction (represented by the pressure concentration isotherm curve on top) wherein the gaseous form of hydrogen and/or its isotopes is transformed to a metallic form of proceeds in four steps: (1) physisorption of gaseous hydrogen and/or its isotopes by van der Waals force; (2) chemisorption via H-H dissociation of exothermic reaction; (3) H atom solvation to form alpha phase solid solution of endothermic reaction; and (4) chemical reaction to form beta phase hydride of exothermic reaction. The desorption process / reaction follows the same but reversed procedure, the desorption process represented by the pressure concentration isotherm curve on the bottom of FIG. 5. The reversible process comes with hysteresis loss due to the irreversibility of energy balance between the exothermic reaction associated with the absorption of hydrogen by the crystalline metallic structure and the endothermic reaction associated with the desorption of hydrogen from the crystalline metallic structure. FIG. 5 illustrates this hysteresis loss by the gap between the two by the pressure-concentration isotherm curves. In FIG. 5, the vertical axis represents the log value of pressure at equilibrium while the horizontal axis represents the concentration of one or more isotopes of hydrogen in the solid solution a phase and in the metal hydride β phase.

[0083] Referring now to FIG. 6, FIG. 6 corresponds to a method of swinging temperature within the closed environment containing the crystalline metallic material and the one or more isotopes of hydrogen under isobaric condition. In one embodiment, increased traffic of hydrogen and/or its isotopes atom inner bulk is realized by inducing interstitial stress within a lattice structure of a crystalline metallic material in a closed environment to generate a plurality of defects and dislocations in the lattice structure by cycling one or more isotopes of hydrogen within the closed environment between a gaseous phase and a hydride phase by varying temperature while maintaining constant pressure. This cycling results in the formation of clusters within the plurality of defects and dislocations generated in the lattice structure, each cluster including multiple atoms of the one or more isotopes of hydrogen. In other words, the number and size of hydrogen clusters is increased by changing the bulk temperature while keeping the gas pressure stable and then the equilibrium plateau pressure changes as shown by the three pressure concentration isotherm curves in FIG. 6. As the plateau region varies with the given gas pressure, it has a drastic effect on the solid solution a phase and the hydride β phase, as represented by the displacement of the dot corresponding to the pressure along a horizontal line. For example, when the bulk temperature is increased, the population of β phase is drastically reduced while the population of the a phase is drastically increased (location of the dot closest to the left margin in FIG. 6); by contrast, when the bulk temperature is decreased, the population of β phase is drastically increased but the alpha phase is drastically decreased (the dot closest to the right margin in FIG. 6).

[0084] Cycling hydrogen within the closed environment between a gaseous phase and a hydride phase β, or between a gaseous phase and a solid solution a phase, or between a hydride phase β and a solid solution a phase, causes or increases interstitial stress within the bulk of the crystalline metallic material due to the structural and density discrepancy between the phases. In other words, varying temperature while maintaining constant pressure induces interstitial stress within the lattices structure of the crystalline metallic structure. As a result, new defects and deformations are generated where hydrogen and/or its isotopes atoms are trapped while they cycle between both phases. In one embodiment, the pressure within the closed environment is set at a predefined value at which an interphase equilibrium between a solid solution a phase and a hydride β phase occurs for the one or more isotopes of hydrogen. Further, the temperature within the closed

environment is varied on either side of a critical temperature T_c at which an inter-phase equilibrium between a solid solution a phase and a hydride β phase occurs for the one or more isotopes of hydrogen. The cycling the one or more isotopes of hydrogen within the closed environment between the gaseous phase and the hydride phase results in switching between a hydrogen absorption process and a hydrogen desorption process within the closed environment. The swinging of temperature while maintain pressure results in the loading and deloading of the one or more isotopes of hydrogen within the lattice structure of the crystalline metallic material, and in the trapping of the one or more isotopes of hydrogen within the plurality of defects and dislocations generated in the lattice structure Cycling the one or more isotopes of hydrogen within the closed environment between a gaseous phase and a hydride phase comprises switching between an exothermic reaction associated with a solid solution a phase and an endothermic reaction associated with the hydride β phase.

[0085] In one embodiment, the crystalline metallic material comprises nanoscale particles to increase the density and size of the clusters formed within the crystalline metallic material. As used herein, nanoscale particles are defined as particles between 1 and 100 nanometres (nm) in size with a surrounding interfacial layer. The interfacial layer is an integral part of a nanoscale particle, fundamentally affecting all of its properties. The interfacial layer typically consists of ions, inorganic and organic molecules. Further, as used herein, a nanoscale particle may also represent a nano-object with all three external dimensions in the nanoscale, whose longest and shortest axes do not differ significantly, with a significant difference typically being a factor of at least 3. In one or more embodiments, microscale / nanoscale particles are structured to form nanoscale voids between its constituents and/or with one or more of layers of stack 126 (see FIG. 1), from which dislocation cores result. Specifically, the thickness of the structure involved is desirably selected to obtain the dislocation site density. Generally, dislocation sites form around the intersections of the microscale / nanoscale structures where a void occurs between layers. With preformed nanoscale voids in the stack 126 (see FIG. 1), loading without cycling can achieve a higher dislocation site and corresponding hydrogen isotope cluster density. [0086] In one embodiment, the population of the one or more isotopes of hydrogen in a hydride β phase is reduced and a population of the one or more isotopes of hydrogen in a solid solution a phase is increased when the temperature is increased. In one embodiment, the population of the one or more isotopes of hydrogen in a hydride β phase is increased and a population of the one or more isotopes of hydrogen in a solid solution a phase is decreased when temperature is decreased.

[0087] Referring now to FIG. 7, FIG. 7 illustrates a method of swinging pressure within the closed environment containing the crystalline metallic material and the one or more isotopes of hydrogen under an isothermal condition. In this embodiment, increased traffic of hydrogen and/or its isotopes atom inner bulk is realized by cycling one or more isotopes of hydrogen within the closed environment between a gaseous phase and a hydride phase by varying pressure while maintaining constant temperature. This results in the formation of clusters within the plurality of defects and dislocations generated in the lattice structure, each cluster including multiple atoms of the one or more isotopes of hydrogen. In other words, the number and size of hydrogen clusters is increased by changing the bulk pressure while keeping the gas temperature stable and then the equilibrium plateau pressure changes as shown in the temperature concentration isobar curves as shown in FIG. 7. As the plateau changes with the given gas temperature, it has a drastic effect on the solid solution a phase and the hydride β phase, as represented by the displacement of the dot corresponding to the temperature along a horizontal line.

[0088] For example, when the bulk pressure is decreased, the population of β phase is drastically reduced while the population of the a phase is drastically increased (location of the dot closest to the left margin in FIG. 7); by contrast, when the bulk pressure is increased, the population of β phase is drastically increased but the alpha phase is drastically decreased (the dot closest to the right margin in FIG. 7). Cycling the hydrogen within the closed environment under such conditions as shown in FIG. 7 between a gaseous phase and a hydride phase causes and increases interstitial stress within the bulk of the crystalline metallic material due to the structural and density discrepancy of both phases; in other words, varying pressure while maintaining constant temperature induces interstitial stress within the lattices structure of the crystalline metallic structure. As a result, new defects and deformations are generated where hydrogen and/or its isotopes atoms are trapped while they cycle between both phases.

[0089] In one embodiment, the temperature within the closed environment is set at a predefined value at which an inter-phase equilibrium between a solid solution a phase and a hydride β phase occurs for the one or more isotopes of hydrogen. Further, the pressure within the closed environment is varied on either side of a predefined pressure P_c at which an inter-phase equilibrium between a solid solution a phase and a hydride β phase occurs for the one or more isotopes of hydrogen. The cycling the one or more isotopes of hydrogen within the closed environment between the gaseous phase and the hydride phase results in switching between a hydrogen absorption process and a hydrogen desorption process within the closed environment.

[0090] The swinging of pressure while maintaining constant temperature results in the loading and deloading of the one or more isotopes of hydrogen within the lattice structure of the crystalline metallic material, and in the trapping of the one or more isotopes of hydrogen within the plurality of defects and dislocations generated in the lattice structure. This cycling the one or more isotopes of hydrogen within the closed environment between a gaseous phase and a hydride phase comprises switching between an exothermic reaction associated with a solid solution a phase and an endothermic reaction associated with the hydride β phase.

[0091] In one embodiment, the crystalline metallic material comprises nanoscale particles to increase the density and size of the clusters formed within the crystalline metallic material. In one embodiment, the population of the one or more isotopes of hydrogen in a hydride β phase is reduced and a population of the one or more isotopes of hydrogen in a solid solution a phase is increased when the pressure is decreased. In one embodiment, the population of the one or more isotopes of hydrogen in a hydride β phase is increased and a population of the one or more isotopes of hydrogen in a solid solution a phase is decreased when pressure is increased.

[0092] Referring now to FIG. 8, FIG. 8 illustrates a method of combining the steps of swinging both temperature and pressure. Particularly, the left side graph of FIG. 8 illustrates pressure concentration isotherms corresponding to increasing temperature while simultaneously reducing pressure. The right side graph of FIG. 8 illustrates pressure concentration isotherms corresponding to decreasing temperature while simultaneously increasing pressure. The steps illustrated in the left side and right graphs are alternated repeatedly to induce interstitial stress within a lattice structure of a crystalline metallic material in a closed environment to generate a plurality of defects and dislocations in the lattice structure. This results in the formation of clusters within the plurality of defects and dislocations generated in the lattice structure, each cluster including multiple atoms of the one or more isotopes of hydrogen. The set of graphs shown in FIG. 8 illustrate that when the population of solid solution a phase and a hydride β phase are more or less equal in a single bulk, increasing the bulk temperature and simultaneously decreasing the gas pressure converts most of the hydrogen to a solid solution a phase as indicated on the left side graph of FIG. 8; similarly, increasing the bulk pressure and simultaneously decreasing the gas temperature converts most of the hydrogen to a hydride β phase as indicated on the right side graph of FIG. 8.

[0093] In this embodiment, increased traffic of hydrogen and/or its isotopes atom inner bulk is realized by cycling one or more isotopes of hydrogen within the closed environment between a gaseous phase and a hydride phase by varying pressure and temperature as illustrated in FIG. 8 to form clusters within the plurality of defects and dislocations generated in the lattice structure. Each cluster includes multiple atoms of the one or more isotopes of hydrogen. In other words, the number and size of hydrogen clusters is increased by changing the bulk pressure and bulk temperature as shown in FIG. 8 alternately and this process of alternating is repeated. As plateau changes with the given gas temperature, it has a drastic effect on the solid solution a phase and the hydride β phase, as represented by the displacement of the dot corresponding to the temperature along a horizontal line.

[0094] For example, when the bulk pressure is decreased and the bulk temperature is simultaneously increased, the population of β phase is drastically reduced while the population of the a phase is drastically increased (location of the dot close to the left margin in the left side graph); by contrast, when the bulk pressure is increased while the bulk temperature is simultaneously reduced, the population of β phase is drastically increased but the alpha phase is drastically decreased (the dot close to the right margin in the right side graph). [0095] Cycling the hydrogen within the closed environment under such conditions as shown in FIG. 8 causes and increases interstitial stress within the bulk of the crystalline metallic material due to the structural and density discrepancy of both phases; in other words, varying pressure and temperature in the manner shown in FIG. 8 induces interstitial stress within the lattices structure of the crystalline metallic structure. As a result, new defects and deformations are generated where hydrogen and/or its isotopes atoms are trapped while they cycle between both phases.

[0096] The cycling the one or more isotopes of hydrogen within the closed environment between the gaseous phase and the hydride phase results in switching between a hydrogen absorption process and a hydrogen desorption process within the closed environment. The swinging of pressure and temperature as illustrated in FIG. 8 results in the loading and deloading of the one or more isotopes of hydrogen within the lattice structure of the crystalline metallic material, and in the trapping of the one or more isotopes of hydrogen within the plurality of defects and dislocations generated in the lattice structure. This cycling of one or more isotopes of hydrogen within the closed environment between a gaseous phase and a hydride phase comprises switching between an exothermic reaction associated with a solid solution a phase and an endothermic reaction associated with the hydride β phase.

[0097] In one embodiment, the crystalline metallic material comprises nanoscale particles to increase the density and size of the clusters formed within the crystalline metallic material. In one embodiment, the population of the one or more isotopes of hydrogen in a hydride β phase is reduced and a population of the one or more isotopes of hydrogen in a solid solution a phase is increased when the pressure is decreased while the temperature is simultaneously increased. In one embodiment, the population of the one or more isotopes of hydrogen in a hydride β phase is increased and a population of the one or more isotopes of hydrogen in a solid solution a phase is decreased when pressure is increased while the temperature is simultaneously decreased.

[0098] The inventors have further observed that when the both bulk temperature and the gas pressure is increased simultaneously there is no drastic change in the respective populations of a phase and β phase materials, as shown in FIG. 9. As shown on the left side graph of FIG. 9, the effect of increasing pressure on the respective populations of a phase and β phase materials is cancelled out by the effect of simultaneously increasing temperature; as shown in the left side graph of FIG. 9, the dot just moves upwards along a vertical line, indicating that no change in the respective populations of a phase and β phase materials has been effectuated.

[0099] Similarly, as shown on the right side graph of FIG. 9, the effect of decreasing pressure on the respective populations of a phase and β phase materials is cancelled out by the effect of simultaneously decreasing temperature; as shown in the right side graph of FIG. 9, the dot just moves downwards along a vertical line, indicating that no change in the respective populations of a phase and β phase materials has been effected.

[00100] By controlling the behavior of phase transition related to the gas pressure and the bulk temperature appropriately, the speed of phase transfer between both phases possibly can be advantageously controlled, and accordingly the rate of the cluster formation can be advantageously controlled. Embodiments of the present invention thus present numerous advantages over known methods of loading and deloading hydrogen within a lattice structure of crystalline metallic materials. Embodiments of the present invention also present numerous advantages over known methods of forming defects and dislocations in the lattice structure of crystalline metallic materials. Further, embodiments of the present invention present numerous advantages over known methods by increasing the number of clusters of hydrogen formed within defects and dislocations in the lattice structure of crystalline metallic materials. Additionally, embodiments of the present invention present numerous advantages over known methods by increasing the size of each of the clusters of hydrogen formed within defects and dislocations in the lattice structure of crystalline metallic materials.

[00101] The present invention may, of course, be carried out in other ways than those specifically set forth herein without departing from essential characteristics of the invention. The present embodiments are to be considered in all respects as illustrative and not restrictive, and all changes coming within the meaning and equivalency range of the appended claims are intended to be embraced therein.

Claims

CLAIMS What is claimed is:

1. A method, comprising:

inducing interstitial stress within a lattice structure of a crystalline metallic material in a closed environment to generate a plurality of defects and dislocations in the lattice structure;

cycling one or more isotopes of hydrogen within the closed environment between a gaseous phase and one or more of a hydride β phase and a solid solution a phase by varying temperature while maintaining constant pressure to form clusters within the plurality of defects and dislocations generated in the lattice structure, each cluster including multiple atoms of the one or more isotopes of hydrogen.

2. The method of claim 1, wherein the pressure is set at a predefined value at which an inter-phase equilibrium between a solid solution a phase and a hydride β phase occurs for the one or more isotopes of hydrogen.

3. The method of claim 1, wherein the temperature is varied on either side of a

critical temperature T_c at which an inter-phase equilibrium between a solid solution a phase and a hydride β phase occurs for the one or more isotopes of hydrogen.

4. The method of claim 1, wherein the varying temperature while maintaining constant pressure induces the interstitial stress within the lattices structure of the crystalline metallic structure.

5. The method of claim 1, further comprising loading and deloading of the one or more isotopes of hydrogen within the lattice structure of the crystalline metallic material.

6. The method of claim 1, wherein the cycling the one or more isotopes of hydrogen within the closed environment between a gaseous phase and a hydride phase comprises phase change of the one or more isotopes of hydrogen between a solid solution a phase and a metal hydride β phase.

7. The method of claim 1, wherein forming the clusters of the one or more isotopes of hydrogen comprises trapping the one or more isotopes of hydrogen within the plurality of defects and dislocations generated in the lattice structure.

8. The method of claim 1, wherein the cycling the one or more isotopes of hydrogen within the closed environment between the gaseous phase and the hydride phase comprises switching between a hydrogen absorption process and a hydrogen desorption process.

9. The method of claim 1, wherein the cycling the one or more isotopes of hydrogen within the closed environment between a gaseous phase and a hydride phase comprises switching between an exothermic reaction associated with a solid solution a phase and an endothermic reaction associated with the hydride β phase.

10. The method of claim 1, wherein the crystalline metallic material comprises

nanoscale particles.

11. The method of claim 1, wherein a population of the one or more isotopes of

hydrogen in a hydride β phase is reduced and a population of the one or more isotopes of hydrogen in a solid solution a phase is increased when the temperature is increased.

12. The method of claim 1, wherein a population of the one or more isotopes of

hydrogen in a hydride β phase is increased and a population of the one or more isotopes of hydrogen in a solid solution a phase is decreased when temperature is decreased.

13. The method of claim 1, further comprising:

thermally insulating the closed environment.

14. A method, comprising: inducing interstitial stress within a lattice structure of a crystalline metallic material in a closed environment to generate a plurality of defects and dislocations in the lattice structure;

cycling one or more isotopes of hydrogen within the closed environment between a gaseous phase and one or more of a hydride β phase and a solid solution a phase by varying pressure while maintaining constant temperature to form clusters within the plurality of defects and dislocations generated in the lattice structure, each cluster including multiple atoms of the one or more isotopes of hydrogen.

15. The method of claim 14, wherein the temperature is set at a predefined value at which an inter-phase equilibrium between a solid solution a phase and a hydride β phase occurs for the one or more isotopes of hydrogen.

16. The method of claim 14, wherein the temperature is varied on either side of a predefined pressure P_c at which an inter-phase equilibrium between a solid solution a phase and a hydride β phase occurs for the one or more isotopes of hydrogen.

17. The method of claim 14, wherein the varying pressure while maintaining constant temperature induces the interstitial stress within the lattices structure of the crystalline metallic structure.

18. The method of claim 14, further comprising loading and deloading of the one or more isotopes of hydrogen within the lattice structure of the crystalline metallic material.

19. The method of claim 14, wherein the cycling the one or more isotopes of

hydrogen within the closed environment between a gaseous phase and a hydride phase comprises phase change of the one or more isotopes of hydrogen between a solid solution a phase and a metal hydride β phase.

20. The method of claim 14, wherein forming the clusters of the one or more isotopes of hydrogen comprises trapping the one or more isotopes of hydrogen within the plurality of defects and dislocations generated in the lattice structure.

21. The method of claim 14, wherein the cycling the one or more isotopes of

hydrogen within the closed environment between the gaseous phase and the hydride phase comprises switching between a hydrogen absorption process and a hydrogen desorption process.

22. The method of claim 14, wherein the cycling the one or more isotopes of

hydrogen within the closed environment between a gaseous phase and a hydride phase comprises switching between an exothermic reaction associated with a solid solution a phase and an endothermic reaction associated with the hydride β phase.

23. The method of claim 14, wherein the crystalline metallic material comprises nanoscale particles.

24. The method of claim 14, wherein a population of the one or more isotopes of hydrogen in a hydride β phase is increased and a population of the one or more isotopes of hydrogen in a solid solution a phase is decreased when the pressure is increased.

25. The method of claim 14, wherein a population of the one or more isotopes of hydrogen in a hydride β phase is decreased and a population of the one or more isotopes of hydrogen in a solid solution a phase is increased when pressure is decreased.

26. The method of claim 14, further comprising:

thermally insulating the closed environment.

27. A method, comprising:

inducing interstitial stress within a lattice structure of a crystalline metallic material in a closed environment to generate a plurality of defects and dislocations in the lattice structure;

cycling one or more isotopes of hydrogen within the closed environment between a gaseous phase and one or more of a hydride β phase and a solid solution a phase by varying temperature and pressure to form clusters within the plurality of defects and dislocations generated in the lattice structure, each cluster including multiple atoms of the one or more isotopes of hydrogen.

28. The method of claim 27, wherein the temperature is varied on either side of a critical temperature T_c and on either side of a predefined pressure P_c at which an inter-phase equilibrium between a solid solution a phase and a hydride β phase occurs for the one or more isotopes of hydrogen.

29. The method of claim 27, wherein the varying the temperature and the pressure induces the interstitial stress within the lattices structure of the crystalline metallic structure.

30. The method of claim 27, further comprising loading and deloading of the one or more isotopes of hydrogen within the lattice structure of the crystalline metallic material.

31. The method of claim 27, wherein the cycling the one or more isotopes of

hydrogen within the closed environment between a gaseous phase and a hydride phase comprises phase change of the one or more isotopes of hydrogen between a solid solution a phase and a metal hydride β phase.

32. The method of claim 27, wherein forming the clusters of the one or more isotopes of hydrogen comprises trapping the one or more isotopes of hydrogen within the plurality of defects and dislocations generated in the lattice structure.

33. The method of claim 27, wherein the cycling the one or more isotopes of

hydrogen within the closed environment between the gaseous phase and the hydride phase comprises switching between a hydrogen absorption process and a hydrogen desorption process.

34. The method of claim 27, wherein the cycling the one or more isotopes of

hydrogen within the closed environment between a gaseous phase and a hydride phase comprises switching between an exothermic reaction associated with a solid solution a phase and an endothermic reaction associated with the hydride β phase.

35. The method of claim 27, wherein the crystalline metallic material comprises

nanoscale particles.

36. The method of claim 27, wherein a population of the one or more isotopes of hydrogen in a hydride β phase is reduced and a population of the one or more isotopes of hydrogen in a solid solution a phase is increased when the temperature is increased.

37. The method of claim 27, wherein a population of the one or more isotopes of hydrogen in a hydride β phase is increased and a population of the one or more isotopes of hydrogen in a solid solution a phase is decreased when temperature is decreased.

38. The method of claim 27, wherein a population of the one or more isotopes of hydrogen in a hydride β phase is increased and a population of the one or more isotopes of hydrogen in a solid solution a phase is decreased when the pressure is increased.

39. The method of claim 27, wherein a population of the one or more isotopes of hydrogen in a hydride β phase is decreased and a population of the one or more isotopes of hydrogen in a solid solution a phase is increased when pressure is decreased.

40. The method of claim 1, further comprising:

thermally insulating the closed environment.