Method for fabricating a three-dimensional energy storage foam based on graphen oxide / vanadiu oxide composite

Abstract

A synthesis method for fabricating a three-dimensional energy storage foam comprising: preparing a first solution by dissolving a pre-determined amount of a polyvinyl alcohol in a pre-heated water, obtaining a second solution by adding a pre-determined amount of a vanadium salt to the first solution, producing a colloid mixture by adding a graphene oxide mixture to the second solution, obtaining a graphene oxide / polyvinyl alcohol / vanadium oxide composite by heating the colloid mixture in a pre-determined temperature under a hydrothermal condition for a pre-determined heating time, and fabricating the three-dimensional energy storage foam by heating the graphene oxide / polyvinyl alcohol / vanadium oxide composite to remove the polyvinyl alcohol under a calcining condition such that a plurality of vanadium oxide with a formula of V2O3 is decorated between the graphene oxide layers. The produced three-dimensional energy storage foam is configured to use as a working electrode for electrochemical hydrogen storage.

Description

Ref- 1403-02-8767METHOD FOR FABRICATING A THREE-DIMENSIONAL ENERGY STORAGE FOAM BASED ON GRAPHEN OXIDE / VANADIU OXIDE COMPOSITETECHNICAL FIELD

[0001] The present disclosure is generally related to an exemplary synthesis method for fabricating an exemplary three-dimensional energy storage foam, and more particularly to an exemplary synthesis method for fabricating an exemplary energy storage graphene oxide / vanadium oxide composite foam with a specific surface area in a range of 2.0 m2 / g to 3.0 m2 / g for electrochemical hydrogen storage.BACKGROUND

[0002] In recent decades, energy demand has increased mainly due to the growth of world population, industrialization and development of countries. However, fossil fuels as the main supplier of the energy demand are non-renewable as well as the continuous consumption of these energy sources has destructive effects such as atmospheric pollution, greenhouse gas emissions, global warming and climate change. Therefore, finding and developing renewable and pollution-free energy sources for the huge energy demand worldwide like sun energy, wind energy, ocean energy, hydrogen, etc. have received more attention as some of renewable energy sources. Among these renewable energy sources, hydrogen is very popular as a clean, nonpolluting, environmentally friendly, non-toxic, versatile, and high energy density energy source. Furthermore, hydrogen is one of the most abundant elements on Earth, and water is its only byproduct.

[0003] Production of hydrogen, for example, from electrolysis of water, storage and then its recovery are the three main steps that must be done for the optimal use of hydrogen as anRef- 1403-02-8767 energy source. There are variety methods for hydrogen storage such as a compress hydrogen, a liquid hydrogen, and a material based hydrogen storage. Hydrogen storage utilizing the compress hydrogen and liquid storage has limitations such as a low storage density, a need for expensive equipment and materials, and safety warnings. In contrast, in material based hydrogen storage method, there is no need to use the expensive and dangerous transportation due to on-site production, storage as well as recovery. In this method, hydrogen can be stored in three different ways in materials: a physical hydrogen storage, a chemical hydrogen storages, and an electrochemical hydrogen storage. Recent years, the electrochemical hydrogen storage as a promising method has received more attention.

[0004] Various materials as an electrode have been introduced for electrochemical hydrogen storage. Carbonaceous materials are one of the most important families of materials used as electrodes for electrochemical hydrogen storage. These materials are cheaper and have good electronic conductivity, high strength-to-weight ratio, low density, chemical stability, and high thermal resistance, making them suitable for electrochemical hydrogen storage applications. Carbon nanotubes, nanofibers, fullerene and graphene and its derivatives (oxide(GO) and reduced graphene oxide (rGO)) are examples of a wide range of the carbon materials that have been used for the electrochemical hydrogen storage.

[0005] On the other hand, vanadium oxide especially in its nanostructure form, due to its layered structure and reduction-oxidation property, can affect an amount of guest atom storage and absorption. Therefore, combination of the vanadium oxide with graphene derivatives like graphene oxide can have a synergic effect on the electrochemical hydrogen storage. This combination can be in a form of composite which a decoration of vanadium oxide particles between a plurality of graphene oxide layers can enhance a strength of the graphene oxide / vanadium oxide composite.Ref- 1403-02-8767

[0006] . Thus, there is a need to develop a facile, cost-effective, and easy-to-use synthesis methods for controlled production of a three-dimensional energy storage graphene oxide / vanadium oxide composite with a high specific surface area and storage capacity wherein the vanadium oxide with a formula of V2O3 is decorated between the plurality of graphene oxide layers.SUMMARY

[0007] This summary is intended to provide an overview of the subject matter of the present disclosure, and is not intended to identify essential elements or key elements of the subject matter, nor is it intended to be used to determine the scope of the claimed implementations. Its sole purpose is to present some concepts of one or more exemplary aspects in a simplified form as a prelude to the more detailed description that is presented later. The proper scope of the present disclosure may be ascertained from the claims set forth below in view of the detailed description below and the drawings.

[0008] One or more exemplary embodiments describe an exemplary synthesis method for fabricating an exemplary a three-dimensional energy storage foam. The exemplary synthesis method may comprise preparing an exemplary first solution by dissolving an exemplary predetermined amount of an exemplary polyvinyl alcohol in an exemplary pre-heated water, obtaining an exemplary second solution by adding an exemplary pre-determined amount of an exemplary vanadium salt to the exemplary first solution, producing an exemplary colloid mixture by adding an exemplary graphene oxide mixture to the exemplary second solution, obtaining an exemplary graphene oxide / polyvinyl alcohol / vanadium oxide composite by heating the exemplary colloid mixture under an exemplary hydrothermal condition for an exemplary pre-determined heating time, and fabricating the exemplary three-dimensional energy storage foam by heating the exemplary graphene oxide / polyvinyl alcohol / vanadiumRef- 1403-02-8767 oxide composite to remove the exemplary polyvinyl alcohol under an exemplary calcining condition. The exemplary three-dimensional energy storage foam may be configured to storing an energy in at least one storage device.

[0009] In one or more exemplary embodiments, ammonium metavanadate may be used to obtain the exemplary first solution. In one or more exemplary embodiments, the exemplary hydrothermal condition to form the exemplary colloid mixture may comprise an exemplary temperature in an exemplary range of 150 °C to 220 °C. In one or more exemplary embodiments, the exemplary pre-determined heating time may be in a range of 2 h to 4 h. In one or more exemplary embodiments, the exemplary calcining condition may comprise an exemplary calcining temperature in an exemplary range of 350 °C to 450 °C in presence of an exemplary reducing atmosphere. In some exemplary embodiments, the exemplary reducing atmosphere may comprise argon, hydrogen, nitrogen, and / or a combination thereof. In an exemplary embodiment, the exemplary reducing atmosphere may comprises an exemplary mixture of argon and hydrogen in an exemplary weight ratio of 95:5. In one or more exemplary embodiments, the exemplary pre-determined amount of the exemplary polyvinyl alcohol may be in an exemplary range of 0.2 g to 0.3 g. In one or more exemplary embodiments, an exemplary concentration of the exemplary graphene oxide mixture may be in a range of 0.1 g / ml to 0.5 g / ml. In one or more exemplary embodiments, the exemplary pre-determined amount of the vanadium salt may be in a range of 0.05 g to 0.30 g. In one or more exemplary embodiments, the exemplary energy storage may be an exemplary electrochemical hydrogen storage. In one or more exemplary embodiments, the exemplary at least one storage device may be an exemplary electrochemical capacitor and / or an exemplary battery. In one or more exemplary embodiments, the exemplary three dimensional energy storage foam may comprise an exemplary graphene oxide / vanadium oxide composite such that an exemplary vanadium oxide formula of the exemplary graphene oxide / vanadium oxide composite may be V2O3 andRef- 1403-02-8767 the exemplary vanadium oxide may be decorated between an exemplary plurality of graphene oxide layers.

[0010] In one or more exemplary embodiments, the exemplary three-dimensional energy storage foam produced by the exemplary synthesis method may comprise an exemplary specific area surface in an exemplary range of 2.0 m2 / g to 3.0 m2 / g. In one or more exemplary embodiments, an exemplary storage capacity of the exemplary three-dimensional energy storage foam may be 30 mAhg1at an exemplary current density of 1 Ag’1. In one or more exemplary embodiments, the exemplary produced three-dimensional energy storage foam may comprise an exemplary specific storage capacity of 23 Fg-1at an exemplary current density of 1 Ag1.

[0011] This Summary may introduce a number of concepts in a simplified format; the concepts are further disclosed within the “Detailed Description” section. This Summary is not intended to configure essential / key features of the claimed subject matter, nor is intended to limit the scope of the claimed subject matter.BRIEF DESCRIPTION OF THE DRAWINGS

[0012] The novel features which are believed to be characteristic of the present disclosure, as to its structure, organization, use and method of operation, together with further objectives and advantages thereof, will be better understood from the following drawings in which an exemplary embodiment will now be illustrated by way of example. It is expressly understood, however, that the drawings are for the purpose of illustration and description only and are not intended as a definition of the limits of the present disclosure. Exemplary embodiments will now be described by way of example in association with the accompanying drawings in which:Ref- 1403-02-8767

[0013] FIG. 1 illustrates flowchart of an exemplary synthesis method for fabricating an exemplary three-dimensional energy storage foam, consistent with one or more exemplary embodiments of the present disclosure;

[0014] FIG. 2 illustrates (a) an exemplary produced graphene oxide / vanadium oxide composite and (b) an exemplary produced graphene oxide / polyvinyl alcohol / vanadium oxide composite foam using an exemplary synthesis method, consistent with one or more exemplary embodiments of the present disclosure;

[0015] FIG. 3 illustrates a plot of XRD pattern analysis of (a) an exemplary graphene oxide, (b) an exemplary graphene oxide / polyvinyl alcohol / vanadium oxide composite, and (c) an exemplary graphene oxide / vanadium oxide composite foam, consistent with one or more exemplary embodiments of the present disclosure;

[0016] FIG. 4 illustrates an exemplary spectra of Fourier transformation infrared spectroscopy (FTIR) of (a) an exemplary graphene oxide / polyvinyl alcohol / vanadium oxide composite and (b) an exemplary graphene oxide / vanadium oxide composite foam, consistent with one or more exemplary embodiments of the present disclosure;

[0017] FIG. 5 illustrates field-emission scanning electron microscope (FESEM) images of (a) an exemplary graphene oxide / polyvinyl alcohol / vanadium oxide composite and (b) an exemplary graphene oxide / vanadium oxide composite foam, consistent with one or more exemplary embodiments of the present disclosure;

[0018] FIG. 6 illustrates a plot of an exemplary cyclic voltammetry (a) an exemplary graphene oxide / polyvinyl alcohol / vanadium oxide composite and (b) an exemplary graphene oxide / vanadium oxide composite foam at a scan rate of 10, 30, 50, 70, and 100 mV / s, consistent with one or more exemplary embodiments of the present disclosure;

[0019] FIG. 7 illustrates a plot of an exemplary cyclic voltammetry (a) an exemplary graphene oxide / polyvinyl alcohol / vanadium oxide composite and (b) an exemplary grapheneRef- 1403-02-8767 oxide / vanadium oxide composite foam at a scan rate of 50 mV / s, consistent with one or more exemplary embodiments of the present disclosure;

[0020] FIG. 8 illustrates a plot of an exemplary specific capacitance of an exemplary graphene oxide / polyvinyl alcohol / vanadium oxide composite and an exemplary graphene oxide / vanadium oxide composite foam at a scan rate of 10, 30, 50, 70, and 100 mV / s, consistent with one or more exemplary embodiments of the present disclosure;

[0021] FIG. 9 illustrates charge / discharge curves of (a) an exemplary graphene oxide / polyvinyl alcohol / vanadium oxide composite and (b) an exemplary graphene oxide / vanadium oxide composite foam at a current density of 1 Ag-1, consistent with one or more exemplary embodiments of the present disclosure; and

[0022] FIG. 10 illustrates a Specific capacitance plot of an exemplary graphene oxide / polyvinyl alcohol / vanadium oxide composite and an exemplary graphene oxide / vanadium oxide composite foam at a current density of 1 Ag1, consistent with one or more exemplary embodiments of the present disclosure.DETAILED DESCRIPTION

[0023] In the following detailed description, numerous specific details are set forth by way of examples to provide a thorough understanding of the relevant teachings related to the exemplary embodiments. However, it should be apparent that the present teachings may be practiced without such details. In other instances, well known methods, procedures, components, and / or circuitry have been described at a relatively high-level, without detail, in order to avoid unnecessarily obscuring aspects of the present teachings.

[0024] The following detailed description is presented to enable a person skilled in the art to make and use the methods and devices disclosed in one or more exemplary embodiments of the present disclosure. For purposes of explanation, specific nomenclature is set forth toRef- 1403-02-8767 provide a thorough understanding of the present disclosure. However, it will be apparent to one skilled in the art that these specific details are not required to practice the disclosed exemplary embodiments. Descriptions of specific exemplary embodiments are provided only as representative examples. Various modifications to the exemplary implementations will be plain to one skilled in the art, and the general principles defined herein may be applied to other implementations and applications without departing from the scope of the present disclosure. The present disclosure is not intended to be limited to the implementations shown, but is to be accorded the widest possible scope consistent with the principles and features disclosed herein.

[0025] Disclosed herein is an exemplary cost-effective and easy-to-use synthesis method for producing an exemplary three-dimensional energy storage foam with a high electrochemical hydrogen storage performance. In an exemplary embodiment, “energy storage foam” may refer to a porous substance with a plurality of nano and / or macro pores that can absorb and store a plurality of hydrogen atom within the plurality of nano and / or macro pores. In an exemplary embodiment, a hydrothermal process may be used for synthesizing an exemplary three-dimensional energy storage foam. In an exemplary embodiment, “hydrothermal process” and / or “hydrothermal method” may refer to a method that a crystalline substance produce from a high-temperature aqueous solution at a high pressure. Some benefits from utilizing an exemplary hydrothermal process may include, but are not limited to, an environmental-friendly and cost-effective method, producing an exemplary crystalline substance with a specific pore size and distribution, and producing a various nanostructure with different morphology by adjusting exemplary parameters, such as solvent, temperature, and pressure.FIG. 1 illustrates flowchart of exemplary synthesis method 100 for fabricating an exemplary three-dimensional energy storage foam, consistent with one or more exemplary embodiments of the present disclosure. In an exemplary embodiment, an exemplary synthesis method 100Ref- 1403-02-8767 may include: preparing an exemplary first solution by dissolving an exemplary pre-determined amount of an exemplary polyvinyl alcohol in an exemplary pre-heated water(102); obtaining an exemplary second solution by adding an exemplary pre-determined amount of an exemplary vanadium salt to the exemplary first solution (104); producing an exemplary colloid mixture by adding an exemplary graphene oxide mixture to the exemplary second solution (106); obtaining an exemplary graphene oxide / polyvinyl alcohol / vanadium oxide composite by heating the exemplary colloid mixture under a hydrothermal condition for an exemplary predetermined heating time (108); and fabricating the exemplary three-dimensional energy storage foam by heating the exemplary graphene oxide / polyvinyl alcohol / vanadium oxide composite to eliminate the exemplary polyvinyl alcohol under an exemplary calcining condition (110). In an exemplary embodiment, the exemplary three-dimensional energy storage foam produced by the exemplary synthesis method 100 may be configured to store an exemplary energy in at least one exemplary storage device.

[0026] In further detail with respect to step 102, step 102 may comprise preparing an exemplary first solution by dissolving an exemplary pre-determined amount of an exemplary polyvinyl alcohol in an exemplary pre-heated water. In an exemplary embodiment, dissolving the exemplary polyvinyl alcohol with an exemplary pre-determined amount in a pre-heated water may include adding an exemplary pre-determined amount of the exemplary polyvinyl alcohol in an exemplary range of 2.0 g to 3.0 g to a pre-demined volume of an exemplary preheated water in an exemplary first container. An exemplary first container may comprise, for example, bur is not limited to, beakers, flasks, bottles, vials, barrels, tanks, buckets, and other types of containers that are well-known by those skilled in the art. In an exemplary embodiment, an exemplary water used for forming an exemplary first solution may include deionized water, distilled water, double-distilled water, or ultrapure water. “Ultrapure water”Ref- 1403-02-8767 may refer to a water that has been purified using a combination of ultrafiltration technologies and ultraviolet photo-oxidation system. In an exemplary embodiment, dissolving the exemplary polyvinyl alcohol with a pre-determined amount in pre-heated water may comprise dissolving 2.0-0.30 g of an exemplary polyvinyl alcohol with an exemplary average molecular weight of 70000-80000 g / mol in a pre-determined volume of pre-heated distilled water in a range of 25 ml to 50 ml with an exemplary temperature in a range of 70 °C to 100 °C, more particularly an exemplary temperature of 75-85 °C, in an exemplary solution tank, while stirring, e.g., using a magnetic stirrer or an agitation machine (with a speed between about 200 rpm and 300 rpm), for a time duration of about 40- 50 minutes.

[0027] In further detail with respect to step 104, step 104 may comprise obtaining an exemplary second solution by adding an exemplary pre-determined amount of an exemplary vanadium salt to the exemplary first solution. In an exemplary embodiment, adding an exemplary vanadium salt with an exemplary pre -determined amount to the exemplary first solution may comprise adding an exemplary vanadium salt powder with a pre-determined amount in an exemplary range of 0.05 g to 0.3 g to an exemplary first solution at an exemplary temperature in an exemplary range of 70 °C to 100 °C in an exemplary container (e.g., an exemplary solution tank) while stirring, e.g., using a magnetic stirrer or an agitation machine (with a speed between about 200 rpm and 300 rpm), for a time duration of about 10-20 minutes. In an exemplary embodiment, adding an exemplary vanadium salt with an exemplary predetermined amount to the exemplary first solution may comprise adding exemplary ammonium metavanadate with a pre-determined amount in an exemplary range of 0.05 g to 0.3 g to an exemplary first solution at an exemplary temperature of 70 °C to 100 °C, more particularly in an exemplary range of 75 °C to 85 °C in an exemplary container (e.g., an exemplary solution tank) while stirring, e.g., using a magnetic stirrer or an agitation machine (with a speed betweenRef- 1403-02-8767 about 200 rpm and 300 rpm), for a time duration of about 10-20 minutes until a color of an exemplary second solution turns to yellow.

[0028] In further detail with respect to step 106, step 106 may comprise producing an exemplary colloid mixture by adding an exemplary graphene oxide mixture to an exemplary second solution. In an exemplary embodiment, adding an exemplary graphene oxide mixture to an exemplary second solution may comprise adding a pre-determined volume of graphene oxide mixture with a pre-determined concentration to an exemplary second solution in an exemplary container (e.g., an exemplary solution tank). In an exemplary embodiment, adding an exemplary graphene oxide mixture to an exemplary second solution may comprise adding 10ml to 15ml of graphene oxide mixture with a pre-determined concentration in a range of 0.1 g / ml to 0.5 g / ml to an exemplary second solution in an exemplary container (e.g., an exemplary solution tank) while stirring, e.g., using a magnetic stirrer or an agitation machine (with a speed between about 200 rpm and 300 rpm), for a time duration of about 4 h to 6 h at a temperature level of about 70- 100 °C. In an exemplary embodiment, adding an exemplary graphene oxide mixture to an exemplary second solution may comprise adding 5ml of graphene oxide mixture with a pre-determined concentration in a range of 0.1 g / ml to 0.5 g / ml, more particularly in a range of 0.10 g / mol to 2.0 g / mol, to an exemplary second solution in an exemplary container (e.g., an exemplary solution tank) while stirring, e.g., using a magnetic stirrer or an agitation machine (with a speed between about . . . rpm and . . . rpm), for a time duration of about 240- 360 minutes at a temperature level of about 75- 85 °C.

[0029] In an exemplary embodiment, preparing an exemplary graphene oxide mixture may comprise adding an exemplary pre-determined amount of an exemplary graphene oxide powder with an exemplary average particle size in a range of lOnm to 50nm to an exemplary pre-determined volume of an exemplary water in an exemplary second container at a room temperature. An exemplary second container may comprise, for example, but is not limited to,Ref- 1403-02-8767 beakers, flasks, bottles, vials, barrels, tanks, buckets, and other types of containers that are well- known by those skilled in the art. In an exemplary embodiment, an exemplary water used for forming an exemplary graphene oxide mixture may include deionized water, distilled water, double-distilled water, or ultrapure water. In an exemplary embodiment, preparing an exemplary graphene oxide mixture may comprise adding 0.1g to 0.5 g of an exemplary graphene oxide powder with an exemplary average particle size in a range of lOnm to 50nm to distilled water with an exemplary pre-determined volume in a range of 10ml to 15ml in an exemplary second container at a room temperature.

[0030] In further detail with respect to step 108, step 108 may comprise obtaining an exemplary graphene oxide / polyvinyl alcohol / vanadium oxide composite by heating an exemplary colloid mixture under a hydrothermal condition for an exemplary pre-determined heating time. In an exemplary embodiment, heating an exemplary colloid mixture may comprise introducing an exemplary colloid mixture from an exemplary first container to an exemplary third container and placing the exemplary third container containing an exemplary colloid mixture to an exemplary synthesis reactor, more particularly an exemplary hydrothermal synthesis reactor, and heating exemplary third container containing an exemplary colloid mixture under an exemplary hydrothermal condition that an exemplary hydrothermal condition may comprise an exemplary temperature in a range of 150 °C to 200 °C, more particularly 180 °C for an exemplary heating time in a range of 2h to 4h. An exemplary third container may comprise, for example, but is not limited to, vials, bottles, tanks, buckets, flasks, beakers, barrels, and other types of containers that are well-known by those skilled in the art.

[0031] In further detail with respect to step 110, step 110 may comprise fabricating an exemplary three-dimensional energy storage foam by heating an exemplary graphene oxide / polyvinyl alcohol / vanadium oxide composite to eliminate the exemplary polyvinyl alcohol as well as reduce an exemplary vanadium oxide under an exemplary calciningRef- 1403-02-8767 condition. In an exemplary embodiment, heating an exemplary graphene oxide / polyvinyl alcohol / vanadium oxide composite may comprise introducing an exemplary graphene oxide / polyvinyl alcohol / vanadium oxide composite to an exemplary heating apparatus and exposing an exemplary graphene oxide / polyvinyl alcohol / vanadium oxide composite to an exemplary calcining condition for an exemplary calcining duration time. In an exemplary calcining condition may comprise an exemplary calcining temperature in an exemplary range of 350 °C to 450 °C in presence of an exemplary reducing atmosphere. An exemplary heating apparatus may comprise, for example, but is not limited to, a tube furnace, a vacuum furnace, or any other heating apparatuses that are well-known for those skilled in the art.. In an exemplary embodiment, argon, nitrogen, hydrogen, and / or a combination thereof can be used as an exemplary reducing atmosphere. In an exemplary embodiment, heating an exemplary graphene oxide / polyvinyl alcohol / vanadium oxide composite may comprise introducing an exemplary graphene oxide / polyvinyl alcohol / vanadium oxide composite to an exemplary heating apparatus (for example an exemplary tube furnace) and exposing an exemplary graphene oxide / polyvinyl alcohol / vanadium oxide composite to an exemplary calcining temperature in an exemplary range of 350 °C to 450 °C for an exemplary calcining duration time in a range of 3 h to 5 h in present of an exemplary mixture of argon and hydrogen which an exemplary weigh ratio of argon to hydrogen (Ar: Hi) may be 95:5.

[0032] In an exemplary embodiment, an exemplary graphene oxide / polyvinyl alcohol / vanadium oxide composite produced by step 108 may be dried at a room temperature for at least 48 h and then an exemplary dried graphene oxide / polyvinyl alcohol / vanadium oxide composite may be transferred to an exemplary heating apparatus to fabricate an exemplary three-dimensional energy storage foam.

[0033] In an exemplary embodiment, an exemplary produced three-dimensional energy storage foam may comprise an exemplary graphene oxide / vanadium oxide composite that anRef- 1403-02-8767 exemplary vanadium oxide in a formula of V2O3 may be decorated between a plurality of graphene oxide layers.

[0034] In an exemplary embodiment, an exemplary produced three-dimensional energy storage foam may comprise a specific surface area in an exemplary range of 2.0 g / m2to 3.0 g / m2.

[0035] In an exemplary embodiment, an exemplary produced three-dimensional energy storage foam may comprise a storage capacity and an exemplary specific storage capacity of 30 mAhg1and 23 F g-1, respectively, at an exemplary current density of 1 Ag1.

[0036] EXAMPLES

[0037] Hereinafter, one or more exemplary embodiments will be described in further detail with reference to examples. It will be obvious to a person having ordinary skill in the art that these examples may be for illustrative purposes only and are not to be interpreted to limit the scope of the present disclosure.Example 1: Synthesis of an Energy Storage Graphene Oxide / Vanadium Oxide Composite Foam

[0038] In this example, exemplary graphene oxide / vanadium oxide composite were synthesized based on an exemplary process similar to synthesis method 100. To synthesize exemplary graphene oxide / vanadium oxide composite, first an exemplary first solution with a may be prepared in a solution tank. In an exemplary embodiment, an exemplary first solution may be prepared by dissolving 2.0-3.0 g polyvinyl alcohol (with an average molecular weight of 70000-80000 g / mol) in 20-30 ml pre-heated distilled water with a temperature of 75-85 °C, followed by stirring at about 200-300 rpm for about 40-50 minutes at a temperature of about 75-85 °C.Ref- 1403-02-8767

[0039] Afterwards, an exemplary second solution may be prepared in the solution tank by adding an exemplary vanadium salt to the exemplary first solution. In an exemplary embodiment, an exemplary second solution may be obtained by adding 0.3g of ammonium metavanadate with a formula of NH4VO3 to the first solution. Followed by stirring at about 200-300 rpm for about 10 h to 14 h at a temperature of about 75-85 °C.

[0040] Following that, an exemplary colloid mixture may be prepared by adding an exemplary graphene oxide mixture to the exemplary second solution. In an exemplary embodiment, an exemplary colloid mixture may be prepared by adding 4ml to 5ml of an exemplary graphene oxide with a concentration of 0.1 -0.2 g / ml to the exemplary second solution at a temperature in a range of 75-85 °C, followed by stirring at about 200-300 rpm for about 20-40 minutes.

[0041] Afterward, an exemplary graphene oxide / polyvinyl alcohol / vanadium oxide composite may be prepared by exposing the exemplary colloid solution to a hydrothermal condition in an exemplary hydrothermal synthesis reactor. In an exemplary embodiment, an exemplary graphene oxide / polyvinyl alcohol / vanadium oxide composite may be produced by pouring the exemplary produced colloid mixture of graphene oxide, polyvinyl alcohol, and NH4VO3 into an exemplary vial and introducing the exemplary vial containing the exemplary graphene oxide / polyvinyl alcohol / NH4VO3 colloid mixture to an exemplary autoclave for exposing the exemplary colloid mixture to an exemplary heating temperature in a range of 150- 200 °C at a high pressure 100-200 bar for about 2h to 4h, followed by, drying the exemplary produced graphene oxide / polyvinyl alcohol / vanadium oxide composite at a room temperature for about 24h tO 48 h.

[0042] Following that, an exemplary graphene oxide / vanadium oxide composite foam may be fabricated by heating the exemplary dried graphene oxide / polyvinyl alcohol / vanadiumRef- 1403-02-8767 oxide composite in an exemplary heating apparatus under an exemplary calcining condition. In an exemplary embodiment, an exemplary graphene oxide / vanadium oxide composite foam may be produced by transferring the exemplary dried graphene oxide / polyvinyl alcohol / vanadium oxide composite to an exemplary tube furnace and exposing the exemplary dried graphene oxide / polyvinyl alcohol / vanadium oxide composite to an exemplary reducing atmosphere including a mixture of argon and hydrogen in a weight ratio of 95:5 at a calcining temperature about 350-450 °C for about 3h to 5h. In this exemplary embodiment, an exemplary graphene oxide / vanadium oxide composite foam may be prepared which an exemplary vanadium oxide with a formula of V2O3 may be decorated between the exemplary graphene oxide layers and the exemplary polyvinyl alcohol may be eliminated. The exemplary produced graphene oxide / vanadium oxide composite foam may be used as an exemplary electrochemical hydrogen storage material in an exemplary capacitor.

[0043] Furthermore, in an exemplary embodiment, an exemplary dried graphene oxide / poly vinyl alcohol / vanadium oxide composite (GPVC) may be produced similar to method 100 without exposing to an exemplary calcining condition as mentioned- above to compare the dried graphene oxide / polyvinyl alcohol / vanadium oxide composite to the exemplary produced graphene oxide / vanadium oxide composite foam (GVCF). Fig. 2 a-b illustrates an exemplary produced graphene oxide / polyvinyl alcohol / vanadium oxide composite (GPVC) and graphene oxide / vanadium oxide composite foam (GVCF), respectively, consistent with one or more exemplary embodiments of the present disclosure. An exemplary compositions and calcining condition (temperature and reducing atmosphere) of the produced dried graphene oxide / polyvinyl alcohol / vanadium oxide composite (GPVC) as well as graphene oxide / vanadium oxide composite foam (GVCF), are listed in Table. 1.Table.l: composition and calcining condition of exemplary produced GVCF and GPVCRef- 1403-02-8767.. . Graphene oxide C „a ,lci .ni .ng ,, , .Sample , . PVA (g .) N ..H..4V . O..3 ( .g .) „ Temperat ,ure . R . educi ,ng mixture (g / ml) ” ” AtmosphereI ^7GVCF 0.1-0.2 2.0-3.0 0.3 350-450 Ar:H2(95:5) wt%GPVC 0.1-0.2 2.0-3.0 0.3Example 2: Characterization of Graphene Oxide / Vanadium Oxide Composite Foam

[0044] In this example, exemplary produced graphene oxide / vanadium oxide composite foam (GVCF) and graphene oxide / polyvinyl alcohol / vanadium oxide composite (GPVC) in “Example 1” were characterized by field-emission scanning electron microscopy (FESEM), powder X-ray diffraction (XRD), and Fourier transformation infrared spectroscopy (FTIR) analysis. Average pore radius as well as specific surface area of the exemplary GPVC and GVCF were evaluated using Brunauer-Emmett-Teller (BET) analysis.

[0045] An exemplary GVCF synthesized through an exemplary method similar to method 100 (as set forth in Example 1) may exhibit a rhombohedral crystal structure of the V2O3 phase (JCPDS No. 34-0187), as evidenced by exemplary results of XRD pattern analysis. FIG. 3 illustrates plots of XRD pattern analysis of (a) exemplary graphene oxide (b) exemplary graphene oxide / polyvinyl alcohol / vanadium oxide composite, and (c) exemplary graphene oxide / vanadium oxide composite foam, consistent with one or more exemplary embodiments of the present disclosure. In further detail with respect to XRD plots, results from the XRD analysis demonstrated that addition of the vanadium oxide precursor cause formation of V5O12.6H2O (JCPDS No. 45-1401) after applying the exemplary hydrothermal conditions. While, appearance of peaks at angles of 24.3, 33.1, 36.3, and 54.2 degrees (29) correspond to the (012), (104), (110), and (116) planes after the calcination step confirms the formation of vanadium trioxide, Notably, no phase impurity was detected in this analysis.Ref- 1403-02-8767

[0046] FTIR spectra of exemplary produced GPVC and GVCF confirmed vanadium's presence by detecting oxygen-vanadium bonds in a range of 1006 cm1to 1013 cm1and 732 cm1to 747 cm-1 (FIG.4 (a-b))). Peaks centered at 559 cm1, 749 cm1, and 991 cm1is related to asymmetric / symmetric vibrations of V-O-V and V=O bonds, respectively., and the band at 997 cm1is attributed to the symmetric stretching of the (V3+=O) bond. Furthermore, a broad peak at 3441 cm1is related to the O-H stretching vibration of hydroxyl groups. Also, the peaks at 1085 cm1, 1430 cm1, and 1648 cm1are attributed to stretching vibrations of the C-O-C, OH, and C=C bonds, respectively. Additionally, the peak at 2947 cm1is corresponded to stretching vibrations of the methylene group (CH2). As illustrated in FIG.4b , a gradual decrease in the intensity of C=C and CO2 peaks of exemplary synthesized GVCF is observed which indicates that reducing oxygen content in exemplary synthesized GVCF occurred due to applying an exemplary calcining conditions. This reduction could also be attributed to lattice structure defects caused by the incorporation of vanadium atoms.

[0047] Furthermore, FIG. 5 (a-b) and (c-d) illustrate field-emission scanning electron microscope (FESEM) images of exemplary synthesized GPVC and exemplary synthesized GVCF, respectively. FESEM images demonstrate variations in nanoparticle morphology before and after calcination. Exemplary synthesized GVCF shows a formation of vanadium oxide particles with a higher crystallinity as well as porosity compare to exemplary synthesized GPVC, due to elimination of organic materials and functional oxygen groups. Therefore, the graphene oxide foam loaded with oxide particles exhibits structural advantages for hydrogen storage.

[0048] In addition, the exemplary BET results reveal that specific surface area of exemplary produced GPVC and GVCF is about 1.7 g / m2and 2.7 g / m2, respectively. Calcination of the graphene oxide / vanadium oxide composite foam improves the exemplary surface area due to eliminating the exemplary polyvinyl alcohol results in increasing theRef- 1403-02-8767 crystallinity of vanadium oxide. A higher specific surface area of exemplary synthesized GVCF can increase hydrogen adsorption due to enhancing interaction between exemplary synthesized GVCF as an exemplary working electrode and electrolyte.

[0049] Furthermore, exemplary produced GPVC and GVCF indicate an average pore radius of 29.0 nm and 6.8 nm, respectively. The exemplary porous structure of exemplary synthesized products is corresponded to the presence of nitrogen under an exemplary hydrothermal conditions as well as addition of NH4VO3as a vanadium source. The addition of N2during hydrothermal treatment increases the average pore size, while calcination reduces the average pore size due to PVA combustion.

[0050] Example 3: Electrochemical Hydrogen Storage Performance of Graphene Oxide / Vanadium Oxide Composite Foam

[0051] In this example, electrochemical hydrogen storage performance of exemplary fabricated graphene oxide / vanadium oxide composite foam (GVCF) as well as exemplary fabricated graphene oxide / polyvinyl alcohol / vanadium oxide composite (GPVC) in “Example 1” were evaluated in presence of KOH aqueous solution (3M) by cyclic voltammetry (CV) at scan rates of 10, 30, 50, 70, and 100 mV s’1and galvanostatic charge / discharge (GCD) at a current density of 1 A g1.

[0052] The electrochemical behavior as well as hydrogen adsorption / desorption process of exemplary synthesized GPVC and GVCF were examined by cyclic voltammetry (CV) at various scan rates of 10, 30, 50, 70, and 100 mV s’1. The exemplary results of CV (as illustrated in FIG.6) indicate that a hydrogen storage primarily occurs through an exemplary electrochemical doublelayer adsorption due to the absence of exemplary redox peaks in both CV profiles of GPVC and GVCF. Furthermore, GPVC and GVCF indicates an exemplary anodic peaks at -0.5V and cathodic peaks at -1.07V that confirm an effective hydrogen oxidation and adsorption by these two synthesized products. These results illustrate that presence of vanadium oxide can induceRef- 1403-02-8767 a significant surface area modification. Presence of decorated vanadium trioxide on graphene oxide layers of exemplary GVCF resulted in a higher specific surface area as well as micropore volume compared to exemplary GPVC that can enhance hydrogen storage capacity and electrochemical performance of exemplary GVCF due to promoting an exemplary interaction between exemplary GVCF as the working electrode and electrolyte.

[0053] FIG.7 illustrates an exemplary cyclic voltammetry (CV) plot of (a) exemplary GPVC and (b) exemplary GVCF at a scan rate of 50 mV s’1, consistent with one or more exemplary embodiments of the present disclosure. As illustrated in FIG.7, exemplary GVCF indicated a higher hydrogen adsorption. The exemplary results suggest that hydrogen atom adsorption enhance on surface of exemplary GVCF due to presence of vanadium trioxide decorated on surface of graphene oxide layers.

[0054] Furthermore, presence of vanadium oxide with formula of V2O3 in exemplary GVCF can enhance exemplary specific storage capacity of exemplary GVCF in various scan rates as illustrated in FIG.8. As can be seen in FIG.8, exemplary specific storage capacities of exemplary GVCF at scan rates of 10, 30, 50, 70, and 100 mV s’1are 23.0, 16.0, 12.3, 10.4, and 8.3 Fg’1, respectively, at a current density of 1 Ag’1. While, exemplary specific storage capacities of exemplary GPVC at these scan rates are 5.17, 3.60, 3.10, 2.70, and, 2.30 Fg’1, respectively, at a current density of 1 Ag’1. These exemplary results, confirm that chemical and physical structure of vanadium (crystalline V2O3) has a significant effect on electrochemical hydrogen storage of an exemplary graphene oxide foam. On the other hand increasing the scan rates from 10 to 100 mV-s-i results in decreased the specific storage capacity due to reduced reaction efficiency between exemplary synthesized products as the working electrode and electrolyte.

[0055] FIG. 9 illustrates charge / discharge curves of (a) exemplary graphene oxide / polyvinyl alcohol / vanadium oxide composite (GPVC) and (b) exemplary grapheneRef- 1403-02-8767 oxide / vanadium oxide composite foam (GVCF) at a current density of 1 Ag-1, consistent with one or more exemplary embodiments of the present disclosure. As illustrated in FIG.9, presence of exemplary vanadium oxide on the surface of exemplary graphene oxide has increased an exemplary charge / discharge rate as well as an exemplary charge / discharge capacity. An exemplary charge / discharge rate of exemplary GPVC is about 50 seconds while an exemlary GVCF’s charge / discharge rate was reached to 220 seocnds at exemplary current density of 1 Ag1. These exemplary results indicates that a greater hydrogen absorption was occurred in exemplary electrolyte by increasing exemplary charge / discharge rate resulted in an increament of exemplary storage hydrogen capacity

[0056] Additionally, a storage capacity of 7.2 mAh g1for exemplary graphene oxide / polyvinyl alcohol / vanadium oxide composite (GPVC) is reached to 30 mAh g1for exemplary graphene oxide / vanadium oxide composite foam (GVCF) at a current density 1 Ag1(FIG.10). These exemplary results confirmed that calcining exemplary GPVC under a calcining temperature in a range of 350 to 450 C and synthesizing exemplary graphene oxide / vanadium oxide composite foam can decorate vanadium oxide particles with a formula of V2O3 in a crystalline form between a graphene oxide layers as well as eliminating exemplary polyvinyl alcohol results in providing more sites for hydrogen atom adsorption, leading to increasing storage capacity of exemplary graphene oxide / vanadium oxide composite foam (GVCF).

[0057] All these exemplary results confirm that the exemplary disclosed method consistent with one or more exemplary embodiments of the present disclosure for synthesizing an exemplary graphene oxide / vanadium oxide composite foam has a significant effect on electrochemical hydrogen storage performance of the produced product and exemplary produced graphene oxide / vanadium oxide composite foam is a suitable candidate as an energy storage substrate.Ref- 1403-02-8767

[0058] While the foregoing has described what are considered to be the best mode and / or other examples, it is understood that various modifications may be made therein and that the subject matter disclosed herein may be implemented in various forms and examples, and that the teachings may be applied in numerous applications, only some of which have been described herein. It is intended by the following claims to claim any and all applications, modifications and variations that fall within the true scope of the present teachings.

[0059] Unless otherwise stated, all measurements, values, ratings, positions, magnitudes, sizes, and other specifications that are set forth in this specification, including in the claims that follow, are approximate, not exact. They are intended to have a reasonable range that is consistent with the functions to which they relate and with what is customary in the art to which they pertain.

[0060] The scope of protection is limited solely by the claims that now follow. That scope is intended and should be interpreted to be as broad as is consistent with the ordinary meaning of the language that is used in the claims when interpreted in light of this specification and the prosecution history that follows and to encompass all structural and functional equivalents. Notwithstanding, none of the claims are intended to embrace subject matter that fails to satisfy the requirement of Sections 101, 102, or 103 of the Patent Act, nor should they be interpreted in such a way. Any unintended embracement of such subject matter is hereby disclaimed.

[0061] Except as stated immediately above, nothing that has been stated or illustrated is intended or should be interpreted to cause a dedication of any component, step, feature, object, benefit, advantage, or equivalent to the public, regardless of whether it is or is not recited in the claims.

[0062] It will be understood that the terms and expressions used herein have the ordinary meaning as is accorded to such terms and expressions with respect to their corresponding respective areas of inquiry and study except where specific meanings have otherwise been setRef- 1403-02-8767 forth herein. Relational terms such as first and second and the like may be used solely to distinguish one entity or action from another without necessarily requiring or implying any actual such relationship or order between such entities or actions. An element proceeded by “a” or “an” does not, without further constraints, preclude the existence of additional identical elements in the process, method, article, or apparatus that comprises the element.

[0063] Unless otherwise stated, all measurements, values, ratings, positions, magnitudes, sizes, and other specifications that are set forth in this specification, are approximate, not exact. They are intended to have a reasonable range that is consistent with the functions to which they relate and with what is customary in the art to which they pertain.

[0064] It will be understood that the terms and expressions used herein have the ordinary meaning as is accorded to such terms and expressions with respect to their corresponding respective areas of inquiry and study, except where specific meanings have otherwise been set forth herein. Relational terms such as “first” and “second” and the like may be used solely to distinguish one entity or action from another without necessarily requiring or implying any actual such relationship or order between such entities or actions.

[0065] The Abstract of the Disclosure is provided to allow the reader to quickly ascertain the nature of the technical disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims. In addition, in the foregoing Detailed Description, it may be seen that various features are grouped together in various implementations. This is for purposes of streamlining the disclosure, and is not to be interpreted as reflecting an intention that the claimed implementations require more features than are expressly recited in each claim. Rather, as the following claims reflect, inventive subject matter lies in less than all features of a single disclosed implementation. Thus, the following claims are hereby incorporated into the Detailed Description, with each claim standing on its own as a separately claimed subject matter.Ref- 1403-02-8767While various implementations have been described, the description is intended to be exemplary, rather than limiting and it will be apparent to those of ordinary skill in the art that many more implementations and implementations are possible that are within the scope of the implementations. Although many possible combinations of features are shown in the accompanying figures and discussed in this detailed description, many other combinations of the disclosed features are possible. Any feature of any implementation may be used in combination with or substituted for any other feature or element in any other implementation unless specifically restricted. Therefore, it will be understood that any of the features shown and / or discussed in the present disclosure may be implemented together in any suitable combination. Accordingly, the implementations are not to be restricted except in light of the attached claims and their equivalents. Also, various modifications and changes may be made within the scope of the attached claims.

Claims

Ref- 1403-02-8767What is claimed is:

1. A synthesis method for fabricating a three-dimensional energy storage foam comprising: preparing a first solution by dissolving a pre-determined amount of a polyvinyl alcohol in a pre-heated water; obtaining a second solution by adding a pre-determined amount of a vanadium salt to the first solution; producing a colloid mixture by adding a graphene oxide mixture to the second solution; obtaining a graphene oxide / polyvinyl alcohol / vanadium oxide composite by heating the colloid mixture in a pre-determined temperature under a hydrothermal condition for a predetermined heating time; and fabricating the three-dimensional energy storage foam by heating the graphene oxide / polyvinyl alcohol / vanadium oxide composite to remove the polyvinyl alcohol under a calcining condition, wherein the three-dimensional energy storage foam is configured to storing an energy in at least one storage device .

2. The synthesis method of claim 1, wherein the vanadium salt is ammonium metavanadate.

3. The synthesis method of claim 1 or 2, wherein the three dimensional energy storage foam comprises graphene oxide / vanadium oxide composite wherein a vanadium oxide formula of the graphene oxide / vanadium oxide composite is V2O3 which is decorated between a plurality of graphene oxide layers.Ref- 1403-02-87674. The synthesis method of claim 1, wherein the hydrothermal condition comprises a temperature in a range of 150 °C to 220 °C.

5. The synthesis method of claim 1, wherein the pre-determined heating time is in a range of 2 h to 4 h.

6. The synthesis method of claim 1, wherein the calcining condition comprises a calcining temperature in a range of 350 °C to 450 °C in presence of a reducing atmosphere.

7. The synthesis method of claim 5, wherein the reducing atmosphere comprises argon, hydrogen, nitrogen, or a combination thereof.

8. The synthesis method of claim 5, wherein the reducing atmosphere comprises a mixture of argon and hydrogen in a weight ratio of 95: 5.

9. The synthesis method of claim 1, wherein the pre-determined amount of the polyvinyl alcohol is in a range of 0.2 g to 0.3 g.

10. The synthesis method of claim 9, wherein a concentration of the graphene oxide mixture is in a range of 0.1 g / ml to 0.5 g / ml.

11. The synthesis method of claim 1 or 2, wherein the pre-determined amount of the vanadium salt is in a range of 0.05 g to 0.30 g.

12. The synthesis method of claim 1, wherein the energy is an electrochemical hydrogen.

13. The synthesis method of claim 1, wherein the at least one storage device is an electrochemical capacitor and a battery.

14. A three-dimensional energy storage foam produced by a method of any one of claims 1-13.

15. The three-dimensional energy storage foam of claim 14, wherein a specific area surface of three-dimensional energy storage foam is in a range of 2.0 m2 / g to 3.0 m2 / g.Ref- 1403-02-876716. The three-dimensional energy storage foam of claim 14, wherein a storage capacity of the three-dimensional energy storage foam is 30 mAhg1at a current density of 1 Ag-1.

17. The three-dimensional energy storage foam of claim 14, wherein a specific storage capacity of the three-dimensional energy storage foam is 23 F g-1at a current density of 1 Ag1.

18. A synthesis method for fabricating an energy storage graphene oxide / vanadium oxide composite foam comprising: preparing a first solution by dissolving an amount of a polyvinyl alcohol in a range of 0.2 g to 0.3 g in a pre-heated waterat at a temperature of 70 °C to 80 °C ; obtaining a second solution by adding an amount of a vanadium salt in a range of 0.05 g to 0.30 g to the first solution; producing a first colloid mixture by adding a graphene oxide mixture to the second solution in a concentration in a range of 0.1 g / ml to 0.5 g / ml; obtaining a graphene oxide / polyvinyl alcohol / vanadium oxide composite by heating the colloid mixture at a temperature of 150 °C to 220 °C under a hydrothermal condition for a predetermined heating time in a range of 2 h to 4 h; and fabricating the graphene oxide / vanadium oxide composite foam by heating the graphene oxide / polyvinyl alcohol / vanadium oxide composite at a calcining temperature of 350 °C to 450 °C to remove the polyvinyl alcohol under a reducing atmosphere of argon and hydrogen at an argon: hydrogen weight ratio of 95:5, wherein a vanadium oxide formula is V2O3 which is decorated through a plurality of graphene oxide layers.

Images