Magnetic carbon nanomaterial and its manufacturing method

Abstract

To provide a method and a device for manufacturing a magnetic carbon nano material product that may include carbon nano-tubes (CNTs) (at least a portion of which are magnetic CNTs (mCNTs)).SOLUTION: The method and the device use carbon dioxide (CO2) as a reactant in an electrolytic reaction to produce mCNTs. In one embodiment according to the present disclosure, a magnetic additive component is included as a reactant in the method and as part of one or more components in the system or composition to facilitate the magnetic material addition process, the carbide nucleation process, or both during the electrosynthesis reaction to produce magnetic carbon nano-materials.SELECTED DRAWING: Figure 1C

Description

[Technical Field]

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims priority to and the benefit of U.S. Provisional Patent Application No. 63 / 022,284, filed May 8, 2020, which is incorporated herein by reference in its entirety.

[0002] Technical Field

[0002] This disclosure relates generally to the production of carbon nanomaterials. In particular, this disclosure relates to methods, systems and compositions for producing magnetic carbon nanomaterials. [Background technology]

[0003]

[0003] Multi-walled carbon nanotubes (CNTs) consist of concentric walls of cylindrical graphene sheets. Graphene is a sp 2 CNTs are two-dimensional, honeycomb-structured materials formed by a single layer of hybrid orbital carbon atoms. CNTs have the highest measured tensile strength of any material (93,900 MPa). CNTs have many useful properties, including high electrical and thermal conductivity, flexibility, and they can also be chemically modified. These useful properties mean that CNTs have a steadily increasing number of applications.

[0004]

[0004] A known process by which CNTs are produced is chemical vapor deposition, CVD. CVD of CNTs is expensive and it has a high carbon footprint. Summary of the Invention [Means for solving the problem]

[0005]

[0005] Embodiments of the present disclosure relate to methods, systems, and compositions for producing electrosynthesized carbon nanomaterial (CNM) products comprising various nanostructures, including carbon nanotubes (CNTs), at least some of which are magnetic CNTs (mCNTs) or other magnetic carbon nanostructures or morphologies. The methods and apparatus can use carbon dioxide (CO2) as a carbon source, where the carbon is a reactant in an electrolysis reaction to produce magnetic CNM (mCNM) products, which may include mCNTs. The electrolysis reaction effects mass transfer of carbon from the carbon source to the mCNM. In certain embodiments of the present disclosure, iron is included as a reactant in the method and as part of one or more components in the apparatus to facilitate the magnetic material addition process, the carbide nucleation process, or both, during the electrolysis reaction to produce mCNM products comprising mCNTs containing iron or iron carbide. In other embodiments of the present disclosure, nickel or nickel carbide is included as a reactant in the method and as part of one or more components in the apparatus to facilitate the magnetic material addition process, the carbide nucleation process, or both, during the electrolytic reaction to make mCNM products comprising mCNTs containing nickel or nickel carbide.

[0006]

[0006] Certain embodiments of the present disclosure relate to a method for making an mCNM product. The method includes heating an electrolyte medium to obtain a molten electrolyte medium. The molten electrolyte medium is then placed between an anode and a cathode of an electrolytic cell. The method further includes placing a magnetic additive component in the electrolytic cell. The method also includes applying an electric current to the cathode and anode in the electrolytic cell and recovering the mCNM product from the cathode.

[0007]

[0007] Certain embodiments of the present disclosure relate to methods for selecting one or more specific structural / morphological properties of mCNM products, which can be influenced by a magnetic field with respect to their position and / or their orientation. Without being bound by any particular theory, the mCNM products can be used in one or more medical applications, such as drug delivery and imaging; for precise positioning; in consumer electronics; in information storage; in wastewater treatment; in electrochemical sensors; and / or as catalysts in various chemical reactions.

[0008] As used herein, the term "selecting a nanomaterial morphology" refers to any process that contributes to controlling the structure and / or morphology of an electrosynthesized mCNM product. In certain embodiments of the present disclosure, the selected morphology of the mCNM may include the following CNM morphologies: carbon nanotubes, carbon nanofibers, carbon nano-onions, carbon nanoscaffolds, carbon nanospheres, carbon nanohelices, carbon nanoplatelets, graphene, or a combination thereof. In certain embodiments of the present disclosure, selecting a nanomaterial morphology may result in an electrosynthesized mCNM product that is a portion, a majority, substantially all, or all of a single CNM morphology. For example, selecting a nanomaterial morphology may include applying a nanomaterial selection component, with respect to current and / or chemical composition, to produce an electrosynthesized mCNM product that is a portion, a majority, substantially all, or all of one of mCNTs, magnetic carbon nanofibers, magnetic carbon nano-onions, magnetic carbon nanoscaffolds, magnetic carbon nanospheres, magnetic carbon nanohelices, magnetic carbon nanoplatelets, or magnetic graphene.

[0009] In some embodiments of the present disclosure, selecting a nanomaterial morphology includes applying a current to the cathode and the anode as a direct current (DC). For example, a DC electrolytic current can select for mCNM products that include a CNT morphology.

[0010] In some embodiments of the present disclosure, the step of selecting a nanomaterial morphology includes applying an electric current to the cathode and the anode as an alternating current (AC). For example, an AC electrolysis current can select a CNM product having a nano-onion morphology.

[0011]

[0011] In another embodiment, the step of selecting a nanomaterial morphology includes adding ZnO to a molten electrolyte medium and applying an AC electrolysis current that can select a CNM product having a graphene platelet morphology.

[0012] In another embodiment, the step of selecting a nanomaterial morphology includes adding iron oxide to an electrolyte medium and selecting a high density current for carbon nanohelix production.

[0013] In another embodiment, the step of selecting the nanomaterial morphology includes adding MgO to a molten electrolyte medium and selecting an electrical current for hollow carbon nanosphere production.

[0014]

[0014] Certain embodiments of the present disclosure relate to a system including an electrolytic cell for producing one or more magnetic carbon nanomaterial products. The electrolytic cell includes one or more walls defining a plenum and an anode and a cathode positioned within the plenum. The plenum is configured to receive and hold a molten electrolyte medium between the anode and the cathode. The electrolytic cell is further configured to receive magnetic material additive or carbide growth components, optional nanomaterial selection components, and an electric current applicable to the anode and cathode to initiate an electrolytic reaction to produce the one or more magnetic carbon nanomaterial products.

[0015]

[0015] Without being bound by any particular theory, embodiments of the present disclosure relate to an electrolytic reaction in which carbon dioxide (CO2) is split in a molten electrolyte medium to produce mCNM products comprising carbon nanotubes (mCNTs) via a magnetic material addition process, a carbide nucleation process, or both. Magnetic carbon nanomaterials comprising mCNTs have a variety of applications, such as medical treatments that direct treatment to a localized region of interest. Magnetic carbon nanomaterials comprising mCNTs can also be used as renewable catalysts.

[0016] Other embodiments of the present disclosure relate to electrosynthesis processes for producing mCNM products in the absence of CO. Without being bound by any particular theory, certain embodiments of the present disclosure relate to electrolytic reactions that partition carbonate salts in a molten electrolyte medium to provide a carbon source for producing mCNM products comprising carbon nanotubes (mCNTs) by a magnetic material addition process, a carbide nucleation process, or both.

[0017]

[0017] Certain embodiments of the present disclosure relate to the use of a container made of a material containing iron and / or nickel to receive and hold a molten electrolyte medium. Additionally or alternatively, iron and / or nickel from the anode can migrate to the cathode as carbon nanotubes grow. For example, energy dispersive X-ray spectroscopy (EDS) elemental analysis confirms the presence of iron in the carbon nanotubes, and X-ray diffraction (XRD) analysis confirms the presence of iron carbide. Excess iron in the electrolyte medium can be achieved by using an iron-containing container, using an iron-rich alloy such as Incoloy for the anode, using an iron-containing alloy for the cathode, providing an additional source of iron through an iron-based additive that can be introduced into the electrolyte medium, the electrolyte medium itself, or a combination thereof. Rather than a nucleation promoter, excess iron can result in magnetic material additions, i.e., graphene layers, also known as graphitic carbon, coated iron carbide nodules on the outer surface of the structure in mCNT products such as mCNTs, and iron carbide in the structure of mCNMs such as mCNTs.

[0018]

[0018] Certain embodiments of the present disclosure relate to a composition that is an electrolyte medium for making a magnetic carbon nanomaterial product. The electrolyte medium includes a carbonate salt; and a magnetic material additive component or a carbide growth component, or both.

[0019]

[0019] Without being bound by any particular theory, by using CO2 from the atmosphere or CO2 from anthropogenic sources as a carbon source to provide carbon as a reactant in the electrolytic reactions of the present disclosure, embodiments of the present disclosure can reduce the greenhouse gas footprint of processes and systems for making mCNM products, which may include mCNTs and / or other magnetic nanostructures.

[0020]

[0020] These and other features of the present disclosure will become more apparent in the following detailed description, in which reference is made to the accompanying drawings. [Brief explanation of the drawings]

[0021] [Figure 1A]

[0021] Figure 1 shows two photographs and one line drawing: Figure 1A is a photograph of an electrolysis unit according to an embodiment of the present disclosure. [Figure 1B] FIG. 2 is a line graph showing electrolysis gas output concentration (%) over time (h) recovered from the headspace of an electrolysis cell during an electrolysis reaction in Li2CO3 at approximately 770°C, where line Y1 represents carbon dioxide concentration without Li2O, line Z1 is oxygen without Li2O, line Y2 represents carbon dioxide with 1 m Li2O, and line Z2 represents oxygen with 1 m Li2O. [Figure 1C]

[0021] A photograph of a carbon nanomaterial product according to an embodiment of the present disclosure bonded to a magnet. [Figure 2A]

[0022] Figure 2 shows three images and one line graph of a carbon nanomaterial product according to an embodiment of the present disclosure: Figure 2A is a scanning electron microscope (SEM) image of a carbon nanomaterial product (scale bar is 50 μm). [Figure 2B]

[0022] Transmission electron microscope (TEM) image of the carbon nanomaterial product (scale bar is 200 nm). [Figure 2C]

[0022] Figure 2C is another TEM image of the carbon nanomaterial product at a higher magnification than the image in Figure 2C (scale bar is 2 nm). [Figure 2D] 2C is a line graph showing the inter-wall spacing of 10 carbon nanotubes in the carbon nanomaterial product taken along line 2C in FIG. 2C. [Figure 3A]

[0023] 3A and 3B show SEM images of a carbon nanomaterial product according to an embodiment of the present disclosure: Figure 3A is an SEM image at a first magnification (scale bar is 200 μm); [Figure 3B]

[0023] Second, SEM image at higher magnification (scale bar is 10 μm). [Figure 3C]

[0023] Another SEM image at a third magnification (scale bar is 10 μm). [Figure 3D]

[0023] High resolution SEM image at first magnification (scale bar is 3 μm). [Figure 3E]

[0023] Second, a high-resolution SEM image at higher magnification (scale bar is 1 μm). [Figure 4A]

[0024] Figure 4 shows the results of X-ray diffraction (XRD) analysis of carbon nanomaterial products made according to embodiments of the present disclosure. Figure 4A shows the XRD analysis when the electrolyte medium used in the method of manufacture was melted about one day before starting the electrolysis process. [Figure 4B]

[0024] The XRD analysis is shown when the electrolyte medium used in the method of manufacture is freshly melted. [Figure 4C]

[0024] Figure 1 shows XRD of a library of compounds related to carbon nanomaterial products. [Figure 5A]

[0025] Figure 5 shows energy dispersive X-ray spectroscopy (EDS) of three points of a carbon nanomaterial product made according to an embodiment of the present disclosure when the electrolyte medium used in the method of manufacture was melted about one day before starting the electrolysis process. Figure 5A shows data obtained at a first location within the product. [Figure 5B]

[0025] Data obtained at a second location within the product is shown. [Figure 5C]

[0025] Data obtained at a third position within the product are shown. [Figure 6]

[0026] 1 shows EDS elemental analysis data including a top row showing bright field (BF), dark field (DF), and high angle annular dark field (HAADF) images from a high-resolution TEM of a first region (in the rectangle added to the image) of a carbon nanomaterial product made in accordance with an embodiment of the present disclosure taken at a first magnification (scale bar is 500 nm); a middle row showing BF, DF, and HAADF images taken from a TEM of a first region of a carbon nanomaterial product made in accordance with an embodiment of the present disclosure taken at a second, higher magnification (scale bar is 50 nm); and a bottom row showing the presence / absence of carbon (left image), iron (middle image), and nickel (right image). [Figure 7]

[0027] 1 shows EDS elemental analysis data including a top row showing bright field (BF), dark field (DF), and high angle annular dark field (HAADF) images from a high-resolution TEM of a second region (in the rectangle added to the image) of a carbon nanomaterial product made in accordance with an embodiment of the present disclosure taken at a first magnification (scale bar is 500 nm); a middle row showing BF, DF, and HAADF images taken from a TEM of a first region of a carbon nanomaterial product made in accordance with an embodiment of the present disclosure taken at a second, higher magnification (scale bar is 50 nm); and a bottom row showing the presence / absence of carbon (left image), iron (middle image), and nickel (right image). [Figure 8A]

[0028] 8A and 8B show images of mCNTs formed according to embodiments of the present disclosure. Figure 8A shows SEM images of a CNT product formed by carbon dioxide (CO) partitioning in a molten electrolyte medium at different magnification levels. [Figure 8B]

[0028] Figure 1 shows SEM images of CNT products formed by carbon dioxide (CO2) partitioning in a molten electrolyte medium at different magnification levels. [Figure 8C]

[0028] Figure 1 shows SEM images of CNT products formed by carbon dioxide (CO2) partitioning in a molten electrolyte medium at different magnification levels. [Figure 8D]

[0028] Figure 1 shows TEM images of CNT products formed by CO2 partitioning in molten electrolyte medium at different magnification levels. [Figure 8E]

[0028] Figure 1 shows TEM images of CNT products formed by CO2 partitioning in molten electrolyte medium at different magnification levels. [Figure 8F]

[0028] Figure 1 shows TEM images of CNT products formed by CO2 partitioning in molten electrolyte medium at different magnification levels. [Figure 9A]

[0029] Figure 9 shows images of the product of CNT formation in a cast iron vessel using a brass cathode and a nichrome anode: Figure 9A(i) shows the vessel, Figure 9A(ii) shows a side view of the cathode and anode with the CNT product thereon; Figure 9A(iii) shows a front view of the cathode with the CNT product thereon. [Figure 9B]

[0029] Figure 1 shows an SEM image of the CNT product after it has been released from the cathode at a first magnification. [Figure 9C]

[0029] A second, higher magnification shows the CNT product of Figure 9B. [Figure 9D]

[0029] A third, higher magnification shows the CNT product of Figure 9C. [Figure 9E]

[0029] A fourth, higher magnification shows the CNT product of Figure 9D. [Figure 9F]

[0029] A fifth, higher magnification shows the CNT product of Figure 9E. DETAILED DESCRIPTION OF THE INVENTION

[0022] Detailed Description

[0030] Embodiments of the present disclosure relate to methods, systems, and compositions for producing magnetic carbon nanomaterial (mCNM) products comprising carbon nanostructures, at least some of which are magnetic. At least one example of a magnetic carbon nanostructure is a magnetic carbon nanotube (mCNT). As used herein, the terms "magnetic carbon nanomaterial," "magnetic carbon nanostructure," "magnetic carbon nanotube," and "mCNT" refer generally, or specifically, as the context permits, to carbon nanomaterials containing iron, iron carbide, nickel, nickel carbide, or other magnetic materials, as defined herein below, to the extent that the carbon nanomaterial is mobile by a magnetic field. The present methods and apparatus use carbon dioxide (CO) as a reactant in the electrolytic reaction to produce the mCNM product. In certain embodiments of the present disclosure, iron, nickel, or other magnetic materials are included as a reactant in the method and as part of one or more components in the system to facilitate the magnetic material addition process, the carbide nucleation process, or both, during the electrolytic reaction to produce the mCNM product.

[0023]

[0031] Certain embodiments of the present disclosure relate to a method using an electrolytic reaction to produce an mCNM product. The electrolytic reaction is carried out in an environment with a molten electrolyte medium positioned between an anode and a cathode. Carbon is introduced into the molten electrolyte medium as either pure CO, artificial CO, such as from smokestacks or flue gases, concentrated CO, or CO entrained in the atmosphere. Additionally, iron is present in the environment. The iron can come from materials constituting one or more walls of the electrolytic cell in which the electrolytic reaction takes place, the anode, the cathode, additives added to the electrolyte medium, or a combination thereof. When a current having a substantially constant current density is applied to the anode and the cathode, the CO is split to produce carbon, which combines with the iron to form the mCNM product. As will be appreciated by those skilled in the art, other magnetic materials, such as nickel, can also be combined with the produced carbon to produce the mCNM product.

[0024]

[0032] In contrast to known chemical vapor deposition (CVD) methods for producing CNTs, the physicochemical environment of the disclosed embodiments is an electrochemical process, whereas CVD is chemical. The disclosed embodiments use CO as a reactant, whereas CVD uses organic reactants. The disclosed embodiments use a chemical reaction to form the mCNM product at the interface between the molten electrolyte medium and the solid cathode, whereas CVD generally occurs at a gas-solid interface.

[0025]

[0033] There are also additional subtle differences between the embodiments of the present disclosure and the CVD method. The embodiments of the present disclosure provide a higher density of reactive carbon (molten electrolyte medium) near the growth interface on the cathode. While CVD may or may not apply an electric field to the substrate during the CVD method, the embodiments of the present disclosure always apply a strong electric field that rapidly decreases through the double layer adjacent to the cathode during growth of the mCNM product. CVD is related to transition metal nucleation of carbon to grow CNTs. The ability of carbides to dissolve carbon, thereby nucleating and growing CNTs or mCNTs, has not previously been anticipated in the electrochemical environment of the embodiments of the present disclosure.

[0026]

[0034] Carbon nanomaterials containing iron carbide or other ferromagnetic materials, referred to herein as magnetic carbon nanomaterials, can be coupled to magnets and have attracted interest for a wide range of applications, including medicine and catalysis. Known magnetic materials include, but are not limited to, alloys containing one or more of these magnetic materials, such as iron, nickel, cobalt, gadolinium, samarium, neodymium, and steel, as well as materials with significant, but lesser, ferromagnetic, paramagnetic, or diamagnetic properties. Each of these magnetic materials, sometimes referred to herein as a "magnetic additive component," is contemplated within embodiments of the present disclosure, as are any other materials that can contribute to the formation of mCNM via electrosynthesis methods. There are many uses for mCNM products in medical applications, such as in imaging, including magnetic resonance imaging (MRI), as a tool for targeted drug delivery and imaging, stem cells, and in anti-cancer drugs for the treatment of colon cancer, lymph node cancer, melanoma, and bladder cancer.

[0027]

[0035] The field of magnetic materials, and thus renewable nanoscale and dendritic materials, is being investigated and attracting interest for catalytic applications, with particular applications including mCNTs, magnetic graphene, and magnetic carbon spheres and nano-onion catalysts.

[0028]

[0036] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure belongs.

[0029]

[0037] As used herein, the term "about" refers to about a + / - 10% variation from a given value. It should be understood that such a variation is always included in any given value provided herein, whether or not it is specifically referred to.

[0030]

[0038] As used herein, the term "magnetic" refers to the property of a material that can be affected by or that can generate a magnetic field. When a material is affected by a magnetic field, it can change its orientation to align with the field lines of the magnetic field and / or it can move in response to the presence of the magnetic field.

[0031]

[0039] As used herein, the term "magnetic additive component" refers to a chemical component that can participate in the electrosynthesis method of the present disclosure to create an mCNM product. The magnetic additive component can be a magnetic material addition component or a carbide growth component, or a combination thereof, that can be used in methods, systems, and as part of the compositions of the present disclosure, such that magnetic materials and / or carbides are incorporated into or formed on top of, within, or both of the constituent carbon nanoscale structures of the mCNM product. The term "magnetic material addition component" can be used herein to refer to a chemical component that includes a magnetic material and can participate in creating an mCNM product through a magnetic material addition process. The term "carbide growth component" can be used herein to refer to a carbide chemical component that can participate in creating an mCNM product through a carbide nucleation process. Generally, the magnetic additive component is incorporated into the mCNM product such that one or more constituent nanostructures within the mCNM product are mobile when placed in or near a magnetic field.

[0032]

[0040] Embodiments of the present disclosure will now be described by way of example and by reference to the figures.

[0033]

[0041] Some embodiments of the present disclosure relate to a method for producing an mCNM product, which may include mCNTs. The method includes heating an electrolyte medium to obtain a molten electrolyte medium; positioning the molten electrolyte medium between an anode and a cathode of an electrolytic cell; positioning a magnetic additive component, such as a material-additive component or a carbide-growth component, in the electrolytic cell; applying a current to the cathode and anode in the electrolytic cell; and recovering the mCNM product from the cathode. Optionally, the method further includes selecting the mCNM product to include a higher proportion of a desired nanoscale morphology, also referred to herein as a desired nanostructure.

[0034]

[0042] Heating the electrolyte medium can be accomplished by a variety of means, as will be understood by those skilled in the art. For example, a heating device such as an oven or furnace can be used to heat the electrolyte medium to a temperature sufficient to transition it to a molten liquid state. Thus, any heating device capable of achieving the temperature necessary to heat the electrolyte medium to its melting point is contemplated herein.

[0035]

[0043] In some embodiments of the present disclosure, the electrolyte medium includes one or more carbonates. In some embodiments of the present disclosure, the electrolyte medium includes a lithium carbonate electrolyte including pure Li2CO3 (having a melting point of about 723°C), or Li2CO3 mixed with other carbonates such as Na2CO3, K2CO3, MgCO3, CaCO3, BaCO3, or Li2CO3 mixed with other salts including oxides, borates, sulfates, phosphates, or nitrates.

[0036]

[0044] The molten electrolyte medium is positioned between the anode and cathode of the electrolytic cell. The electrolytic cell can be any type of container capable of maintaining its structural integrity in the face of the electrochemical environment generated during the electrolytic reaction of the present disclosure. The electrolytic cell has one or more walls that can be made of or coated with a desired material.

[0037]

[0045] The magnetic additive component refers to a chemical component that may be a component of the electrolyte medium or that is otherwise added to the electrolyte medium before or during the electrosynthesis method disclosed herein. In certain embodiments of the present disclosure, the magnetic additive component may be a magnetic material additive component or a carbide growth component, or any combination thereof. The magnetic additive component may originate from one or more walls of the electrolytic cell. In certain embodiments of the present disclosure, the magnetic additive component originates from the anode. In certain embodiments of the present disclosure, the magnetic additive component originates from the cathode. In certain embodiments of the present disclosure, the magnetic additive component originates from an iron-based additive added to the electrolyte medium. In certain embodiments of the present disclosure, the magnetic additive component originates from the electrolyte medium. In certain embodiments of the present disclosure, the magnetic additive component originates from one or more walls of the electrolytic cell, the anode, the cathode, an iron-based additive added to the electrolyte medium, or any combination of the electrolyte medium.

[0038]

[0046] The magnetic additive component may be added to the electrolyte medium in any suitable amount. For example, in certain embodiments of the present disclosure, the magnetic additive component is added to the electrolyte medium in an amount of about 0.001 molar to about 10 molar or more. In certain embodiments of the present disclosure, the magnetic additive component is added to the electrolyte medium in an amount of about 0.003 molar to about 3 molar, about 0.01 molar to about 1 molar, or 0.03 molar to about 0.3 molar. As used herein, the term "molar" refers to one mole of magnetic additive component per kilogram of electrolyte medium. In other embodiments of the present disclosure, the magnetic additive component is added in an amount of about 0.03-0.06 molar, 0.07-0.10 molar, 0.03-0.05 molar, 0.03-0.05 molar, 0.10-0.13 molar, 0.14-0.17 molar, 0.18-0.21 molar, 0.22-0.25 molar, or 0.26-0.30 molar. In one preferred embodiment of the present disclosure, the magnetic additive component is added in an amount of about 0.1 molar.

[0039]

[0047] In certain embodiments of the present disclosure, the electrolyte medium can be melted inside the electrolysis cell, or it can be melted outside the cell and transferred thereto. Because the electrolysis reaction can occur over a period of time, thereby causing the molten electrolyte medium to cool, the electrolysis cell can be configured with its own integrated heating device, or it can be configured to be heated by an external heating device external to the electrolysis cell so that the electrolyte medium remains in a molten state for a desired period of time. Additionally, and without being bound by any particular theory, heat can be applied both by the exothermic reaction of CO and by resistive heating generated by the electrolysis overpotential without a heating device.

[0040]

[0048] In certain embodiments of the present disclosure, the electrolysis cell may be configured to maintain the electrolyte medium at at least about 375°C, at least about 400°C, at least about 500°C, at least about 600°C, at least about 650°C, at least about 675°C, at least about 700°C, at least about 725°C, at least about 750°C, at least about 775°C, at least about 800°C, at least about 825°C, at least about 850°C, at least about 875°C, at least about 900°C, or at least about 1000°C.

[0041]

[0049] Anodes can be made of various metals or alloys. Some anodes can be made of materials including nickel, chromium, iron, or combinations thereof. Some non-limiting examples of suitable materials for anodes of the present disclosure include substantially pure nickel, alloys composed substantially mostly of nickel, alloys composed of some nickel, substantially pure chromium, alloys composed substantially mostly of chromium, alloys composed of some chromium, substantially pure iron, alloys composed substantially mostly of iron, alloys composed of some iron, or combinations thereof. For example, Inconel 718 or other Inconels, including, but not limited to, Inconel 600 and Inconel 625, Nichrome A (composed of about 80% nickel and about 20% chromium), Nichrome C (composed of approximately nickel, iron, and chromium), Incoloy alloys (such as Incoloy 800, which is composed of about 40% iron, about 30-35% nickel, and about 19-23% chromium), or combinations thereof, may be suitable for use as anodes in embodiments of the present disclosure. The anode may be planar in shape or of other shapes that are conductive to molten electrolysis and may be made in a variety of sizes to fit within the electrolysis cell.

[0042]

[0050] In some embodiments of the present disclosure, the magnetic additive component may be derived from the anode, and the magnetic additive component may comprise from about 0.001% to about 100% by weight of the total anode materials. In some embodiments of the present disclosure, the magnetic material may comprise from about 0.01% to about 99% by weight of the total anode materials, from about 0.1% to about 90% by weight, or from 1% to about 90% by weight, or from about 10% to about 50% by weight.

[0043]

[0051] In other embodiments of the present disclosure, the magnetic additive component is added in an amount of about 0.01-19 wt%, 10-20 wt%, 10-20 wt%, 30-40 wt%, 40-50 wt%, 50-60 wt%, 60-70 wt%, 70-80 wt%, or 90-100 wt%. In a preferred embodiment of the present disclosure, the weight percentage is 30% to about 50 wt%. In other embodiments of the present disclosure, the magnetic additive component in the anode is added to an alloy containing two or more magnetic materials, such as in an amount of about 80 wt% of one magnetic metal and 20% of another magnetic metal.

[0044]

[0052] The cathode can be made of various metals or alloys. Some cathodes can be made of materials that may include copper, zinc, iron, or combinations thereof. Some non-limiting examples of suitable materials for the cathode of the present disclosure include substantially pure copper, an alloy composed substantially mostly of copper, an alloy composed of some copper, substantially pure zinc, an alloy composed substantially mostly of zinc, an alloy composed of some zinc, substantially pure iron, an alloy composed substantially mostly of iron, an alloy composed of some chromium, substantially pure iron, an alloy composed substantially mostly of iron, an alloy composed of some iron, or combinations thereof. For example, brass, such as Muntz brass, can be suitable for use as a cathode in embodiments of the present disclosure. The cathode can be flat or other shapes that are conductive to molten electrolysis and can be made in various dimensions to fit within the electrolysis cell.

[0045]

[0053] The magnetic additive component may be present in the cathode, and may comprise from about 0.001% to about 100% by weight of the total cathode material. In certain embodiments of the present disclosure, the magnetic additive component may comprise from about 0.01% to about 99% by weight of the total cathode material, from about 0.1% to about 90% by weight, or from 1% to about 90% by weight, or from about 10% to about 50% by weight. In other embodiments of the present disclosure, the magnetic additive component is added to the cathode material in an amount of from about 0.01 to 19% by weight, 10 to 20% by weight, 30 to 40% by weight, 40 to 50% by weight, 50 to 60% by weight, 60 to 70% by weight, 70 to 80% by weight, or 90 to 100% by weight. In a preferred embodiment of the present disclosure, the magnetic additive component is added to the cathode in an amount of from 30% to about 50% by weight of the total cathode material. In other embodiments of the present disclosure, the magnetic additive component in the cathode is added to an alloy containing two or more magnetic additive components, for example, about 80% by weight of one magnetic additive component and 20% by weight of another magnetic additive component, based on the total amount of magnetic additive components in the entire cathode material or based on the total cathode material. Positioning the magnetic additive components in the electrolytic cell includes adding the magnetic additive components, including metal salts and / or carbides, to the electrolytic cell so that the magnetic additive components promote the growth of the mCNM product when the electrolytic reaction occurs. In some embodiments of the present disclosure, the carbides can participate in one or more nucleation reactions that result in the growth of CNTs and mCNTs in the mCNM product. In some embodiments of the present disclosure, the carbides can be magnetic.

[0046]

[0054] In certain embodiments of the present disclosure, the magnetic additive component may be derived as a metal, a metal salt, including but not limited to a metal carbide, or a non-metal carbide, or any combination thereof.

[0047]

[0055] Suitable examples of metal carbides include, but are not limited to: iron carbide, nickel carbide, cobalt carbide, zirconium carbide, chromium carbide, tantalum carbide, hafnium carbide, or any combination thereof.

[0048]

[0056] Suitable examples of non-metallic carbides include, but are not limited to: silicon carbide, germanium carbide, or any combination thereof.

[0049]

[0057] In some embodiments of the present disclosure, the current is applied at a substantially constant current density. For example, the current density of the applied current is about 0.001 A / cm 2 ~About 10A / cm 2 In one embodiment, the current density of the applied current may be about 0.003 A / cm 2 ~About 3A / cm 2 ; approx. 0.01A / cm 2 ~About 1A / cm 2 ; approx. 0.03A / cm 2 ~about 0.6A / cm 2 or about 0.06 A / cm 2 ~about 0.3A / cm 2 In some embodiments of the present disclosure, the current density may be about 0.1 A / cm 2 is.

[0050]

[0058] A molten Li2CO3 electrolyte at 750°C contains an equilibrium concentration of lithium oxide of 0.2 molar, according to equation 1 (EQN.1): Li2CO3 (molten) ⇔ Li2O (dissolved) + CO2 (gas) (EQN.1).

[0051]

[0059] During the process of CO2 molten carbonate electrolysis, small transition metal "seeds" were observed at the ends of the CNT product, indicating that the molten carbonate CNT growth mechanism can be activated by both tip and base transition metal nucleation processes.

[0052]

[0060] The reduction of CO in lithium carbonate electrolyte is a 4e-process that proceeds according to equation 2 (EQN.2), without being bound by any particular theory: Li2CO 3(溶融された) →C (ナノマテリアル;) +O 2(気体) +LiO (溶解された) (EQN.2).

[0053]

[0061] Without being bound by any particular theory, CO2 added to the molten electrolyte medium chemically reacts with lithium oxide to regenerate and reform Li2CO3 according to equation 3 (EQN.3): CO 2(大気又はスタック) +LiO (溶解された) ⇔LiCO 3(溶融された) (EQN.3).

[0054]

[0062] When EQN.2 is combined with EQN.3, this produces a net electrolytic reaction according to the 4e-transfer reaction equation 4 (EQN.4), without being bound by any particular theory: CO 2(気体) →C (ナノマテリアル) +O 2(気体) (EQN.4).

[0055]

[0063] Lithium carbonate melts at approximately 723° C. At temperatures above 800° C., without being bound by any particular theory, two, rather than four, electron reduction becomes increasingly dominant up to 950° C., and the electrolysis product, without being bound by any particular theory, is pure carbon monoxide rather than carbon, according to the 2 e-transfer reaction, Equation 5 (EQN.5): CO 2(気体) +2e - →CO 2(気体) +1 / 2O 2(気体) (EQN.5). [Example]

[0056]

[0064] Example

[0065] Example 1

[0066] To carry out the disclosed method, an electrolyte medium was prepared using lithium carbonate (LiCO, approximately 99.5% purity) and lithium oxide (LiO, approximately 99.5% purity). The electrolyte medium was heated using a heating element until molten, resulting in a molten electrolyte. The molten electrolyte medium was then positioned within an electrolysis cell that included one or more walls to define a plenum therebetween. As described further below, the walls of the electrolysis cell were constructed from (or coated with) stainless steel, such as stainless steel 304, or cast iron. An anode and a cathode were positioned within the electrolysis cell. The anode was constructed from Inconel 718. The anode may be selected to produce oxygen during electrolysis. The cathode was constructed from Muntz brass, an alloy of approximately 59-61% copper and approximately 39-41% zinc with some trace amounts of iron.

[0057]

[0067] When the molten electrolyte medium is positioned within the electrolysis cell and between the anode and cathode, a current is applied to the anode and cathode to initiate the electrolysis reaction. In this example, the current was about 0.5 amperes (A) and was applied at a constant current density.

[0058]

[0068] During the electrolysis reaction, the carbon nanomaterial product was collected at the cathode. When the electrolysis reaction was stopped by removing the current, the cathode was removed from the electrolysis cell and allowed to cool. The carbon nanomaterial product could then be collected from the cooled cathode by tapping. The carbon nanomaterial product was then washed with either deionized water (DI water) or 6M or less hydrochloric acid. Both types of washing yielded similar carbon nanomaterial products, but it was observed that the acid wash accelerated the washing. The washed carbon nanomaterial product was then separated from the washing solution by either paper filtration or centrifugation. It was observed that both separation techniques yielded similar carbon nanomaterial products, but the use of a centrifuge accelerated the separation process.

[0059]

[0069] FIG. 1A shows a photograph of an example stainless steel 304 electrolysis cell used to produce carbon nanomaterial products according to embodiments of the present disclosure. Pure CO gas was bubbled into a molten lithium carbonate electrolyte with and without lithium oxide (1 mole of LiO per kg of LiCO). As seen in FIG. 1B, after a short activation period, the gas phase portion of the electrolysis reaction product increased to approximately 100% oxygen, and no CO escaped the electrolysis reaction. Electrolysis was performed in the stainless steel 304 electrolysis cell of FIG. 1A. Within the electrolysis cell, the anode was made of Inconel 718 and the cathode was made of Muntz brass. During the electrolysis reaction, carbon nanomaterial products grew on the cathode according to EQN.4 above. After cooling and washing, the carbon nanomaterials were found to be carbon nanotubes. The extracted cathode was cooled, and the solid product was easily peeled off the cathode and washed to remove excess electrolyte medium. Unexpectedly, when the electrolysis reaction was carried out in an electrolysis cell with at least some iron in the cell walls, the carbon nanomaterial product was found to be magnetic. As shown in Figure 1C, the magnetic CNTs bound strongly to a magnet.

[0060]

[0070] Example 2

[0071] This example used many of the same steps as Example 1, with one exception being the introduction of atmospheric CO (about 216 ppm CO in ambient air), which was bubbled into the molten electrolyte medium, rather than pure or concentrated CO from air. In this example, the electrolyte medium used was a LiCO molten electrolyte medium that was exposed to hot air for about 24 hours before initiating the electrolysis reaction by applying a current, as in other examples described herein. The anode was a 5 cm 3 anode of Inconel 718. 2 The plate was made of Muntz brass, and the cathode was made of Muntz brass. The carbon nanomaterial produced in this example was also magnetic.

[0061]

[0072] To characterize the structural morphology of the carbon nanomaterial products, the products were imaged using scanning electron microscopy (SEM) and transmission electron microscopy (TEM). X-ray diffraction (XRD) was used to characterize the atomic structure of the carbon nanomaterial products.

[0062]

[0073] The carbon nanomaterial product was collected from the cathode, washed, separated, and analyzed by EDS, a PHENOM Pro Pro-X scanning electron microscope (SEM) equipped with an FEI Teneo LV SEM, and an FEI Teneo Talos F200X transmission electron microscope (TEM). XRD powder diffraction data were collected on a Rigaku Miniflex diffractometer and analyzed using the Jade software package.

[0063]

[0074] The basic morphology of the carbon nanomaterial products was essentially the same whether they were produced in a ceramic (alumina) electrolytic cell or a steel electrolytic cell, with the exception of the observed case when excess iron was introduced from the anode during the electrolytic reaction, as shown in a later example.

[0064]

[0075] Figure 2A is an SEM image revealing a highly uniform carbon nanomaterial product, in this case, carbon nanotubes (CNTs), using CO2 from air as the reactant. In Figure 2A, the scale bar is 2 nm. Figures 2B and 2C are TEM images showing that the CNT walls and the graphene spacing between the CNT walls are expected to be 0.33-0.34 nm (see the distance between the two red bars and between each of the 10 peaks below the double-sided arrow in Figure 2D). In Figure 2B, the scale bar is 200 nm, and in Figure 2C, the scale bar is 2 nm.

[0065]

[0076] Example 3

[0077] Additional magnetic CNTs were produced as part of a carbon nanomaterial product made according to an embodiment of the present disclosure. In this example, magnetic CNTs were produced when the anode did not contain iron.

[0066]

[0078] The electrolysis reaction was carried out using an electrolysis cell having one or more walls lined with nickel or a nickel alloy to reduce the presence of iron within the electrolysis cell. The electrolyte medium was molten LiCO containing about 0.67 m LiO (about 2% by weight compared to the weight of the total electrolyte medium), which was maintained at a temperature of about 770°C. The electrolysis cell was open to air containing CO. The anode was made of Nichrome A and the cathode was made of Muntz brass. The electrolysis reaction was carried out at a current of about 0.1 A / cm. 2 This was achieved by applying a current of 25 A at a substantially constant current density of 1000 kJ / s.

[0067]

[0079] After about 4 hours of electrolysis, the cathode was removed from the electrolysis cell and allowed to cool. The solid carbon nanomaterial product was peeled off from the cathode and washed to remove excess electrolyte medium before microscopic examination.

[0068]

[0080] The carbon nanomaterial product was found to be approximately 98% uniform CNTs as determined by multiple SEM and TEM visual inspections. The coulombic efficiency approached 100% during this electrolysis reaction. The coulombic efficiency of the electrolysis is calculated as the percentage of the applied constant current charge that was converted to carbon as determined by Equation 6 (EQN.6) below: 100%×C 実験的 / C 理論的 (EQN.6).

[0069]

[0081] This is because the cathode (C 実験的 ), Q is the time-integrated charge passed during electrolysis, F is the faraday (96485 As mol -1 e - ), and n = 4 e-mol of tetravalent carbon -1Theoretical mass, determined from reduction, C 理論的 =(Q / nF) × (12.01 g C mol -1 ) is calculated from

[0070]

[0082] Figures 3A, 3B, and 3C are SEM images of the carbon nanomaterial product of Example 3. Figure 3A has a 200 μm scale bar, Figure 3B has a 10 μm scale bar, and Figure 3C has a 10 μm scale bar. Figures 3D and 3E are high-resolution SEM images with 3 μm and 1 μm scale bars, respectively.

[0071]

[0083] Example 4

[0084] Additional magnetic CNTs were produced as part of an mCNM product produced according to an embodiment of the present disclosure. In this example, the magnetic CNTs were produced using two samples of electrolyte media. The first electrolyte media for Sample A was melted approximately one day before starting the electrolysis process; the second electrolyte media used for electrolysis for Sample A was freshly melted.

[0072]

[0085] The electrolysis reaction was carried out using an electrolysis cell having one or more walls made of stainless steel 304. The electrolyte medium was molten Li2CO3 containing about 0.67 m Li2O (about 2% by weight compared to the weight of the total electrolyte medium), which was maintained at a temperature of about 770°C. The electrolysis cell was open to air containing CO2. The anode was made of Nichrome A and the cathode was made of Muntz brass. The electrolysis reaction was carried out at a current of about 0.1 A / cm2. 2 This occurred by applying a current at a substantially constant current density of 25 A.

[0073]

[0086] After about 4 hours of electrolysis, the cathode was removed from the electrolysis cell and allowed to cool. The solid carbon nanomaterial product was peeled off from the cathode and washed to remove excess electrolyte medium before microscopic examination.

[0074]

[0087] FIG. 4A shows the x-ray diffraction (XRD) results for Sample A. FIG. 4B shows the XRD results for Sample B. FIG. 4C shows the library XRD of compounds related to the products (graphitic carbon, iron carbide, and nickel or chromium lithium oxide). The XRD results for Sample A showed evidence of significantly more iron carbide in the graphitic carbon product than the XRD results for Sample B. There were no obvious signs of corrosion after either electrolysis reaction, and it is clear that the longer prior electrolyte medium immersion of Sample A resulted in more iron carbide in the product. Prominent peaks are observed at 2Φ, x = 19°, y = 26°, and z = approximately 44°. Specifically, compared to the XRD library, both Sample A and Sample B exhibited either chromium or nickel oxide peaks at x and z (see FIGS. 4A and 4B), and both samples exhibited a graphitic peak at y. However, the ratio of peaks in Sample A, which is the relative height of peak z to either peak x or y, compared to Sample B, is significantly higher. The ratio shows a strong contribution of the iron carbide spectrum at y and z. Additionally, there is a doublet peak at approximately 44°, and in Sample A, the dominance of the left-hand peak compared to either the right-hand peak or peak x is consistent with the contribution of iron carbide. The EDS of Sample A is consistent with the XRD results of Sample A, which show elemental analysis at three points on the carbon nanomaterial product: one point with 100.0 atomic percent C, one point with 94.9% C and 5.1% Fe, and one point with 92.4% C, 5.8% Fe, and 1.9% Cr. While the source of the iron that forms the carbides clearly comes from one or more walls of the electrolytic cell, it is clear that another source could be from oxidation of a component of the anode (in the case of an iron-containing anode), as a direct additive to the electrolyte medium, or from a component of the cathode (in the case of an iron-containing cathode), or any combination thereof.

[0075]

[0088] FIG. 5 shows the EDS data of Sample A, which is consistent with the XRD results of Sample A. The EDS data show elemental analysis at three locations on the carbon nanomaterial product: FIG. 5A shows the first location (+ in the inset image of FIG. 5A) containing 94.9% carbon and 5.1% iron. 3Figure 5B shows the EDS data obtained at a second location (see +2 position in the inset image of Figure 5B, scale bar is 10 µm) containing 92.4% carbon, 5.8% iron, and 1.9% Cr; Figure 5C shows the EDS data obtained at a third location with 100.0% atomic percent carbon.

[0076]

[0089] Without being bound by any particular theory, the source of iron for forming the carbide most likely comes from one or more walls of the electrolytic cell. However, another source of iron may be from the oxidation of a component of the anode (in the case of an iron-containing anode), as a direct iron-based additive that may be added to the electrolyte medium, such as cast iron powder, iron metal, steel, stainless steel, or other iron-containing metal alloys, or iron oxides, including but not limited to FeO, Fe2O3, Fe3O4, or any other iron-containing salt, or otherwise, or from a component of the cathode (in the case of an iron-containing cathode), or any combination thereof.

[0077]

[0090] Figures 6 and 7 are EDS (including bright field (BF), dark field (DF), and high-angle annular dark field (HAADF)) images from a high-resolution TEM of two different regions of the synthesized mCNM product. The first region (shown in Figure 6) is in the hollow core of the carbon nanotube, where the CNT product has carbon composite walls and no metal in the core. The second region (shown in Figure 7) is the metallic core of the carbon nanotube, where primarily iron and a small amount of nickel are observed.

[0078]

[0091] Example 5

[0092] Additional magnetic CNTs were produced as part of a carbon nanomaterial product made according to an embodiment of the present disclosure. In this example, the magnetic CNTs were produced in excess iron.

[0079]

[0093] The electrolysis reaction was carried out using an electrolysis cell having one or more walls made of stainless steel 304. The electrolyte medium was molten Li2CO3. The electrolysis cell was open to air containing CO2. The anode was made of Incoloy alloy (composed of about 40% iron, about 30-35% nickel, and about 19-23% chromium), and the cathode was made of Muntz brass. The electrolysis reaction was carried out at a current of about 0.1 A / cm 2 This was achieved by applying a current of 8 A at a substantially constant current density of 1000 kJ / s.

[0080]

[0094] After about 4 hours of electrolysis, the cathode was removed from the electrolysis cell and allowed to cool. The solid carbon nanomaterial product was peeled off from the cathode and washed to remove excess electrolyte medium before microscopic examination.

[0081]

[0095] It was noted that at high iron contents, the anode may have continuously released iron oxide during the electrolysis reaction, which is due to the fact that the electrolysis reaction was carried out at a current of 0.1 A / cm 2 , which occurred in pure Li2CO3, the measured coulombic efficiency was observed to drop to about 89%.

[0082]

[0096] Figures 8A, 8B, and 8C show SEM images of the carbon nanomaterial product from this Example 5. The scale bars in these images are 30 μm, 20 μm, and 10 μm, respectively. Figures 8D, 8E, and 8F show TEM images of the carbon nanomaterial product from this Example 5. The scale bars in these images are 500 nm, 50 nm, and 10 nm, respectively. The carbon nanomaterial product contained at least some magnetic CNTs, as shown in Figure 8. Unlike the CNTs shown in Figures 2 and 3, the CNTs shown in Figure 8 contain graphene-coated nodules, which are visible on the exterior of the CNTs, and the interior of the CNTs is partially filled with deposits. Similar nodules and filling were observed in iron carbide-driven CNT growth using chemical vapor deposition (CVD). In these CVD-formed CNTs, the interior of the nodules and CNT filling were previously identified as iron carbide. As shown in the TEM image in Figure 8F, the interstitial spacing between layers is only 0.20 nm, which is significantly smaller than the 0.33-0.34 nm graphene interstitial layers between CNT graphene walls, as shown in Figure 2D. The 0.20 nm interstitial separation observed in the carbon nanomaterial product of Example 6 appears similar to separation previously identified in carbon nanostructures; in those previous structures, the interstitial separation was identified as iron carbide.

[0083]

[0097] Example 6

[0098] Based on the examples described above, it was observed that electrolysis reactions carried out in a Li2CO3 molten electrolyte medium with a low concentration of added Li2O or an electrolyte medium that has been aged for 24 hours can result in a higher yield of uniform CNTs in the carbon nanomaterial product than an equivalent pure Li2CO3 electrolyte medium that has not been aged. This leads to the idea that electrolysis reactions carried out using a pure unaged molten Li2CO3 electrolyte medium, but in a cast iron vessel rather than a stainless steel vessel, may promote the formation of iron carbide with a graphitic structure, resulting in a more uniform carbon nanomaterial product of the electrolysis reaction.

[0084]

[0099] The electrolysis reaction of Example 6 was carried out using an electrolysis cell, which was a cast iron vessel (iron containing 2-4.3% carbon, see Figure 9A(i)) with a diameter of about 10 cm and a height of about 5 cm. The electrolyte medium was Li2CO3 that was heated inside the cast iron vessel overnight to remove the surface layer of the vessel. Then, about 300 g of fresh Li2CO3 was added to the vessel and heated to about 770 °C to serve as the molten electrolyte medium. The electrolysis cell was open to air containing CO2. The anode was made of Nichrome and the cathode was made of Muntz brass. The electrolysis reaction was carried out at a current of about 0.1 A / cm2. 2 This was achieved by applying a current of 2 A at a substantially constant current density of .

[0085]

[0100] After about 4 hours of electrolysis, the cathode was removed from the electrolysis cell and allowed to cool (see Figure 9A(ii) and (iii)). The solid carbon nanomaterial product was peeled off from the cathode and washed to remove excess electrolyte medium before microscopic examination.

[0086]

[0101] Figures 9B-9F show SEM images of the carbon nanomaterial product of this Example 6. Figure 9B has a 200 μm scale bar, Figure 9C has a 20 μm scale bar, Figure 9D has a 5 μm scale bar, and Figures 9E and 9F each have a 10 μm scale bar. The magnetic CNTs within the carbon nanomaterial product were highly uniform and had a high aspect ratio (length to diameter). The Coulombic efficiency, as measured by EQN.6, approached 100%, and the product was uniform (approximately 98% pure), ultrathin, magnetic carbon nanotubes.

[0087]

[0102] Without being bound by any particular theory, the examples described herein provide ferromagnetic carbon nanotubes as a product of CO2 bubbled through a molten electrolyte medium during the electrolysis reaction, or by exposure to CO2-containing air or other sources of CO2. The mechanism for producing mCNTs appears to be via a magnetic material addition process or a carbide nucleation process, rather than a transition metal-mediated process. In Example 6, it was also observed that the use of a cast iron vessel as an electrolytic cell for CO2 electrolysis using a molten lithium carbonate electrolyte medium produced highly uniform mCNTs with high aspect ratios in an efficient Coulombic manner. The present application provides, for example, the following inventions. [Claim 1] 1. A method for producing a magnetic carbon nanomaterial, comprising: (a) heating an electrolyte medium to obtain a molten electrolyte medium; (b) positioning said molten electrolyte medium between an anode and a cathode of an electrolytic cell; (c) introducing a magnetic additive component into said electrolytic cell; (d) introducing a carbon source into the electrolysis cell; (e) applying a current to the cathode and the anode in the electrolytic cell; and (f) recovering a magnetic carbon nanomaterial product from the cathode. A method comprising: [Claim 2] The method of claim 1 , wherein the magnetic additive component comprises a magnetic material additive component, a carbide growth component, and any combination thereof. [Claim 3] The method of claim 1 , further comprising selecting a nanomorphology of constituent elements of the magnetic carbon nanomaterial product. [Claim 4] The method of claim 3 , wherein the step of selecting a nanomaterial morphology selects the magnetic carbon nanomaterial product to comprise a magnetic carbon nanotube product. [Claim 5] 4. The method of claim 3, wherein the step of selecting a nanomaterial morphology selects the magnetic carbon nanomaterial product to comprise a magnetic carbon platelet product. [Claim 6] 4. The method of claim 3, wherein the step of selecting a nanomaterial morphology selects the magnetic carbon nanomaterial product to comprise a magnetic graphene product. [Claim 7] 4. The method of claim 3, wherein the step of selecting a nanomaterial morphology selects the magnetic carbon nanomaterial product to comprise a magnetic carbon nano-onion product. [Claim 8] 4. The method of claim 3, wherein the step of selecting a nanomaterial morphology selects the magnetic carbon nanomaterial product to comprise a magnetic, hollow carbon nanosphere product. [Claim 9] The method of claim 1 , wherein the magnetic carbon nanomaterial product is coupled to a magnet. [Claim 10] The method of claim 2 wherein the carbide growth component is a metal carbide. [Claim 11] 11. The method of claim 10, wherein the metal carbide is one of iron carbide, nickel carbide, cobalt carbide; zirconium carbide, chromium carbide, tantalum carbide, hafnium carbide, and any combination thereof. [Claim 12] 12. The method of claim 11, wherein the metal carbide is iron carbide. [Claim 13] The method of claim 2 , wherein the carbide growth component is a non-metallic carbide. [Claim 14] 14. The method of claim 13, wherein the non-metallic carbide is one of silicon carbide, germanium carbide, and any combination thereof. [Claim 15] The method of claim 1 , wherein the electrolysis cell comprises one or more walls constructed from steel, stainless steel, and any combination thereof. [Claim 16] 10. The method of claim 1, wherein the electrolytic cell comprises one or more walls constructed from iron, cast iron, and any combination thereof. [Claim 17] 10. The method of claim 1, wherein the electrolytic cell comprises one or more walls coated with a coating comprising nickel, a nickel alloy, iron, cast iron, and any combination thereof. [Claim 18] The method of claim 1 , wherein the magnetic carbon nanomaterial product comprises the magnetic additive component. [Claim 19] The method of claim 1 , wherein the magnetic carbon nanomaterial product comprises the magnetic additive component as one or more nodules in the magnetic carbon nanomaterial product. [Claim 20] 20. The method of claim 19, wherein the nodules are coated with one or more layers of graphitic carbon. [Claim 21] 3. The method of claim 2, wherein the magnetic material additive component is one or more of iron, nickel, cobalt, gadolinium, samarium, neodymium, steel and other alloys containing one or more magnetic materials having ferromagnetic, paramagnetic or diamagnetic properties. [Claim 22] The method of claim 2 , wherein the magnetic additive component originates from one or more walls of the electrolytic cell. [Claim 23] The method of claim 2 , wherein the magnetic additive component is derived from the anode. [Claim 24] The method of claim 2 , wherein the magnetic additive component is derived from the cathode. [Claim 25] The method of claim 2 , wherein the magnetic additive component is derived from an iron-based additive added to the electrolyte medium. [Claim 26] The iron-based additive may be cast iron powder, iron metal, steel, stainless steel, another iron-containing metal alloy, iron oxide, FeO, Fe 2 O 3 , Fe 3 O 4 , any other iron-containing salt, and any combination thereof. [Claim 27] The method of claim 2 , wherein the magnetic additive component is derived from the electrolyte medium. [Claim 28] 10. The method of claim 1, wherein the carbon source is carbon dioxide, the electrolyte medium, or both. [Claim 29] 10. Use of the carbon nanomaterial product of claim 9 in one or more medical applications. [Claim 30] 10. Use of the carbon nanomaterial product of claim 9 in one or more biomedical applications. [Claim 31] 10. Use of the carbon nanomaterial product of claim 9 as a catalyst. [Claim 32] 10. Use of the carbon nanomaterial product of claim 9 for one or more of medical imaging, precision positioning, consumer electronics, information storage, wastewater treatment and electrochemical sensors. [Claim 33] 10. The carbon nanomaterial product of claim 1, comprising magnetic carbon nanotubes. [Claim 34] 1. A system for producing a magnetic carbon nanomaterial product, said system comprising: (a) an electrolytic cell including one or more walls defining a plenum; (b) an anode and a cathode positioned within the plenum, the plenum configured to receive an electrolyte medium therebetween; and (c) Magnetic additive component Including, wherein the electrolytic cell is further configured to receive an electrical current applicable to the anode and the cathode to initiate an electrolytic reaction to produce the magnetic carbon nanomaterial product. [Claim 35] 35. The system of claim 34, wherein the magnetic additive component comprises a magnetic material additive component, a carbide growth component, or both. [Claim 36] 35. The system of claim 34, wherein the electrolysis cell comprises one or more walls comprising steel, stainless steel, or any combination thereof. [Claim 37] 35. The system of claim 34, wherein the electrolysis cell includes one or more walls comprising iron or cast iron. [Claim 38] 35. The system of claim 34, wherein the electrolysis cell comprises one or more walls coated with a coating comprising nickel, a nickel alloy, iron, cast iron, and any combination thereof. [Claim 39] 35. The system of claim 34, wherein the plenum is further configured to receive a nanomaterial selection component. [Claim 40] 35. The system of claim 34, further comprising a heating device for melting the electrolyte medium and / or maintaining the electrolyte medium in a molten state. [Claim 41] 36. The system of claim 35, wherein the carbide growth component is magnetic. [Claim 42] 35. The system of claim 34, further comprising a collecting magnet for attracting carbon nanomaterial product from the cathode of the cell. [Claim 43] 35. The system of claim 34, wherein the electrolytic cell is further configured to maintain the molten electrolyte medium at a temperature of at least about 650°C. [Claim 44] 35. The system of claim 34, wherein the anode is made of a material comprised of nickel, iron, chromium, or any combination thereof. [Claim 45] 35. The system of claim 34, wherein the magnetic additive component is derived from the one or more walls, the anode, the cathode, an iron-based additive added to the electrolyte medium, the electrolyte medium, and any combination thereof. [Claim 46] 1. An electrolyte medium for producing a magnetic carbon nanomaterial product, comprising: (a) carbonate; and (b) Magnetic additive component an electrolyte medium comprising: [Claim 47] 47. The electrolyte medium of claim 46, wherein the carbonate comprises a carbide growth component. [Claim 48] 47. The electrolyte medium of claim 46, wherein the magnetic additive component is a magnetic material additive component, a carbide growth component, and any combination thereof. [Claim 49] 47. The electrolyte medium of claim 46, wherein the carbonate is an alkali carbonate, an alkaline earth carbonate, or any combination thereof. [Claim 50] 47. The electrolyte medium of claim 46, wherein the carbonates include oxides, borates, sulfates, nitrates, chlorides, chlorates, phosphates, and combinations thereof. [Claim 51] 47. The electrolyte medium of claim 46, wherein the magnetic additive component is an iron-based additive. [Claim 52] The iron-based additive may be cast iron powder, iron metal, steel, stainless steel, another iron-containing metal alloy, iron oxide, FeO, Fe 2 O 3 , Fe 3 O 4 , any other iron-containing salt, and any combination thereof. [Claim 53] 47. The electrolyte medium of claim 46, wherein the magnetic additive component is present in an amount of from about 0.001 Molar to about 10 Molar or more. [Claim 54] 47. The electrolyte medium of claim 46 in a molten state. [Claim 55] 10. A magnetic carbon nanomaterial product produced by the method of claim 1.

Claims

1. 1. A method for producing a magnetic carbon nanomaterial product, comprising: (a) heating an electrolyte medium to obtain a molten electrolyte medium; (b) positioning the molten electrolyte medium between an anode and a cathode of an electrolytic cell; (c) introducing a magnetic additive component into the electrolytic cell; (d) introducing a carbon source into the electrolytic cell; (e) applying a current to the cathode and the anode in the electrolytic cell; and (f) recovering the magnetic carbon nanomaterial product from the cathode. Including, The magnetic carbon nanomaterial product is movable by a magnetic field; and The magnetic additive component is incorporated externally, internally, or both, into the magnetic carbon nanostructures that are constituents of the magnetic carbon nanomaterial product; method.

2. The method of claim 1 , wherein the magnetic additive component comprises a magnetic material additive component, a carbide growth component, or any combination thereof.

3. 10. The method of claim 1, further comprising selecting the nanomorphology of the constituent structures of said magnetic carbon nanomaterial product to comprise a magnetic carbon nanotube product, a magnetic carbon nanofiber product, a magnetic carbon platelet product, a magnetic graphene product, a magnetic carbon nano-onion product, a magnetic hollow carbon nanosphere product, or any combination thereof.

4. 10. The method of claim 1, wherein the magnetic additive component is one or more of iron, nickel, cobalt, gadolinium, samarium, neodymium, steel, and an alloy including one or more magnetic materials having ferromagnetic properties, paramagnetic properties, diamagnetic properties, or any combination thereof.

5. The method of claim 2 wherein the carbide growth component is a metal carbide.

6. 6. The method of claim 5, wherein the metal carbide is one of iron carbide, nickel carbide, cobalt carbide; zirconium carbide, chromium carbide, tantalum carbide, hafnium carbide, and any combination thereof.

7. The method of claim 2 wherein the carbide growth component is a non-metallic carbide.

8. The method of claim 7, wherein the non-metallic carbide is one of silicon carbide, germanium carbide, and any combination thereof.

9. 10. The method of claim 1, wherein the magnetic additive component originates from one or more walls of the electrolytic cell, the anode, the cathode, the electrolyte medium, or any combination thereof.

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