Onium salt-derived materials as chalcogen hosts

Abstract

SOLUTION: By combining two-dimensional (2D) transition metal oxides and / or carbides with sulfur, a cathode for use in Li-S batteries can be formed, which exhibit high capacity and other attractive properties. Accordingly, provided herein is a method comprising forming an admixture comprising sulfur, a 2D transition metal carbide, and an optional conductive material. Also provided is an electrode comprising sulfur, a 2D transition metal carbide, and an optional conductive material. Further provided is an energy cell, the energy cell comprising a first electrode according to the present disclosure. Further provided is a method, the method comprising discharging an energy cell according to the present disclosure or charging an energy cell according to the present disclosure. Also provided is an electric device comprising an energy cell according to the present disclosure.

Description

[Technical field]

[0001] (CROSS REFERENCE TO RELATED APPLICATIONS) This application claims priority to and the benefit of U.S. patent application Ser. No. 63 / 209,318, entitled "Two-Dimensional Titanium CarboOxide Polysulfide Immobilizers," filed June 10, 2021, and U.S. patent application Ser. No. 63 / 210,238, entitled "Onium Salt Derived Materials As Chalcogen Hosts," filed June 14, 2021, the entireties of which are incorporated by reference herein for all purposes.

[0002] (Government Rights) This invention was made with Government support under Grant No. 1919177 awarded by the National Science Foundation. The Government has certain rights in this invention.

[0003] (Technical field) The present disclosure relates to the field of materials useful in rechargeable batteries, and in particular to the field of cathode materials.

[0004] Over the past few decades, the demand for efficient energy storage devices has been steadily increasing due to the limited supply of fossil energy and ever-growing concerns over its negative environmental impact. Due to their high gravimetric energy density, rechargeable lithium-ion batteries have dominated the commercial market. However, lithium-ion chemistry has reached its theoretical limits, creating an urgent need to develop next-generation chemistries.

[0005] Sulfur is a promising cathode material for next-generation rechargeable battery systems, with a theoretical specific capacity of 1675 mAh.g -1This is about five times higher than current lithium-ion battery cathode materials based on layered metal oxides. However, there are significant obstacles to a practical lithium-sulfur (Li-S) cathode (one example of a metal-chalcogen combination) due to inherent problems with sulfur and other chalcogens, such as the low electrical conductivity, dissolution of polysulfides in the electrolyte, and the volume expansion of sulfur during discharge. These problems further shorten the cycle life and result in a low specific capacity.

[0006] Thus, there is a long-felt need for cathode materials that allow the use of sulfur (or other chalcogens) in rechargeable batteries. Summary of the Invention

[0007] To meet the above needs, the present disclosure specifically provides a composition comprising a chalcogen, a 1Da (i.e., a one-dimensional anatase material), and optionally a conductive material, which 1Da can be referred to as a quat-derived nanomaterial (QDN).

[0008] The 1Da may be oxide-based nanofilaments and / or sub-nanofilaments and may optionally contain amounts of carbon (as described herein, the nanofilaments may, for example, contain titanium). The composition may exist as a mesoporous powder in which the powder particulates include oxide-based nanofilaments and / or sub-nanofilaments. The 1Da composition may exist in the form of flakes, e.g., two-dimensional bodies formed (e.g., via self-assembly) with the 1Da filaments. The 1Da composition may also exist as three-dimensional bodies, e.g., nanoparticles.

[0009] 1 Da can exhibit an XRD pattern that exhibits reduced (104) and (105) peaks at about 38° and about 55° two-theta (2θ) when compared to the XRD pattern of nano or bulk anatase. 1 Da nanofilaments and / or sub-nanofilaments, in some embodiments, exhibit Raman spectra very similar to those of bulk anatase, but differ from bulk anatase with respect to their XRD spectra, as described herein.

[0010] 1Da can be obtained by reacting starting materials (e.g., MAX phase materials, carbides, nitrides, borides, sulfides, metals, etc.) with onium salts (ammonium salts, TMAOH, TBAOH, TPAOH, etc.) at temperatures between room temperature and 100° C., for example, under atmospheric pressure. The admixture can optionally include an ammonium salt. 1Da can exist as a two-dimensional material, as described above, but this is not a requirement, and 1Da can also exist as nanoparticles, nanoribbons, nanowhiskers, nanotubes, one-dimensional materials (e.g., fibers), or other forms.

[0011] Also provided is an electrode, the electrode comprising a composition according to the present disclosure (eg, any one of aspects 1-4), the electrode optionally being configured as a cathode.

[0012] Further provided is an energy cell, the energy cell including a first electrode according to the present disclosure (eg, any one of aspects 5-7).

[0013] Also disclosed is a method, the method including discharging an energy cell according to the present disclosure (eg, any one of embodiments 8-13) or charging an energy cell according to the present disclosure (eg, any one of embodiments 8-13).

[0014] Further provided is an electric device including an energy cell according to the present disclosure (eg, any one of embodiments 8-13).

[0015] Also provided is a method that includes forming an admixture that includes a chalcogen, 1Da, and, optionally, a conductive material. [Brief description of the drawings]

[0016] In the drawings, which are not necessarily drawn to scale, like numbers may represent like components in different views. Like numbers with different letter suffixes may represent different instances of the like components. The drawings illustrate generally, by way of example, but not by way of limitation, various aspects discussed in the present specification.

[0017] [Figure 1] (a) Cyclic voltammetry (CV) curves, (b) charge / discharge curves at various current rates for a Li-S cell with a 2D titanium carbide (1 Da) cathode, and (c) cycle stability at 0.2 C. S-loading is 0.8 mg. The capacity remained roughly constant at about 1000 mAh / g for about 300 cycles before fading. [Diagram 2] Electrochemical cycling of two TiC-based 1 Da sulfur composites comprising 70% of the cathode is shown, with an areal loading of 1 mg-cm-2. [Diagram 3] Cyclic voltammetry of 1 Da of TiC formed at 50°C for 5 days with 0.7 mg of sulfur added and various cycle rates. [Figure 4] 1 shows an exemplary rate test of TiC 1Da formed with 0.7 mg sulfur addition at 50° C for 5 days, showing good rate capability at 1C. [Diagram 5] The capacity contribution of 1 Da (TiC) material formed at 50 degrees C for 5 days is shown, showing the low capacity contribution of 1 Da TiC in the voltage window of 1.8 V to 2.6 V, which is the voltage window of lithium sulfur. The specific capacity of TiC 1 Da was 5 mAh / g, decreasing to 1.4 mAh / g at the second cycle. [Figure 6]Visual polysulfide test to observe the interaction of TiC with QDNs. Compared to carbon black, 1Das removed more polysulfides as seen in the photo after 7 days. Two concentrations were performed: 0.5mM and 2mM. [Figure 7] Post-cycle XPS of TiC 1Da and sulfur-based cycled cathodes are shown, demonstrating the appearance of polythionate peaks in the S2p spectrum and elucidating the electrocatalytic mechanism of polysulfide absorbance of TiC 1Da. Without being bound to a particular theory, the appearance of lithium sulfur peaks in both the S2p and Ti2p spectra indicates a Lewis acid-base binding mechanism. [Figure 8] A comparison of pristine TiC 1Da and used TiC 1Da shows a shift in the Ti-O peaks (dark blue vs. pink). Without being bound to any particular theory, this further suggests an interaction between polysulfides and titanium in TiC 1Das, since a change in the coordination number of titanium would cause such a shift in bond energy. [Figure 9] 13. Exemplary SEM of TiC 1Das at various sonication and reaction temperatures. TiC 1Da formed at 80°C for 3 days exhibited a more fibrous surface than TiC 1Da formed at 50°C for 5 days. [Figure 10] 1 shows an exemplary SEM of a cathode according to the present disclosure. [Figure 11] SEM images of the top (left) and bottom (right) surfaces of a used cathode are shown. [Figure 12] 4 shows an SEM photograph (cross section) of a cathode after use. [Figure 13] Exemplary performance of a Li-S cell with 1 Da of TiB (formed at 80° C. for 3 days) doped with 1 mg of sulfur is shown. [Figure 14] Shown is an SEM of a 1Das TiB formed at 80 degrees C for 3 days. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0018] The present disclosure will be more readily understood by reference to the following detailed description of the preferred embodiments and the examples included therein.

[0019] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art. In case of conflict, the present specification, including definitions, shall prevail. Preferred methods and materials are described below, but methods and materials similar or equivalent to those described herein may be used in the practice or testing. All publications, patent applications, patents and other documents described herein are incorporated by reference in their entirety. The materials, methods and examples disclosed herein are illustrative only and are not intended to be limiting.

[0020] The singular forms "a," "an," and "the" include plural referents unless the context clearly indicates otherwise.

[0021] As used herein and in the claims, the term "comprising" may include the embodiments "consisting of" and "consisting essentially of." As used herein, the terms "comprise(s), "include(s), "having," "has," "can," "contain(s)," and variations thereof, are intended to be open-ended transitional phrases, terms, or words that require the presence of the named components / steps and permit the presence of other components / steps. However, such descriptions should also be construed as describing the composition or steps as "consisting of" and "consisting essentially of" the listed components / steps, which permits only the presence of the named components / steps along with impurities that may result therefrom, and excludes other components / steps.

[0022] As used herein, the terms "about" and "at or about" mean that the quantity or value in question may be approximately or approximately the same as the other value specified. As used herein, it is generally understood to be a variation of ±10% of the nominal value unless otherwise indicated or inferred. The term is intended to convey that similar values ​​promote the same results or effects as described in the claims. That is, it is understood that the amounts, sizes, formulations, parameters, and other quantities and characteristics are not and do not have to be exact, but can be approximated and / or larger or smaller as desired, reflecting tolerances, conversion factors, rounding, measurement errors, etc., and other factors known to those skilled in the art. In general, the amounts, sizes, formulations, parameters, or other quantities or characteristics are "about" or "approximate", whether or not they are expressly stated as such. When "about" is used before a quantitative value, it is understood that the parameter also includes the specific quantitative value itself, unless specifically stated otherwise.

[0023] Unless otherwise indicated to the contrary, numerical values ​​should be understood to include numerical values ​​that are the same when reduced to the same significant figure, and numerical values ​​that differ from the stated value by less than experimental error using conventional measuring techniques of the type described herein to determine the numerical value.

[0024] All ranges disclosed herein are inclusive of the recited endpoints and independent of the endpoints (e.g., "between 2 grams and 10 grams, and all intermediate values, including 2 grams, 10 grams, and all intermediate values"). The endpoints of the ranges and any values ​​disclosed herein are not limited to the exact ranges or values, but are sufficiently imprecise to include values ​​that are close to these ranges and / or values. All ranges are combinable.

[0025] As used herein, approximation may be applied to modify any quantitative expression that may vary without resulting in a change in the basic function to which it is related. Thus, a value modified by terms such as "about" or "substantially" may in some cases not be limited to the exact value specified. At least in some cases, an approximation may correspond to the precision of an instrument for measuring the value. The modifier "about" should also be considered to disclose a range defined by the absolute values ​​of the two endpoints. For example, the phrase "about 2 to about 4" also discloses a range of "2 to 4". The term "about" may refer to plus or minus 10% of the indicated numerical value. For example, "about 10%" may indicate a range of 9% to 11%, and "about 1" may mean 0.9 to 1.1. Other meanings of "about" may be apparent from the context, such as rounding, so for example, "about 1" may mean 0.5 to 1.4. Additionally, the term "comprising" should be understood to have the open-ended meaning of the term "including," but also includes the closed meaning of the term "consisting." For example, a composition comprising components A and B may be a composition comprising A, B, and other components, but may also be a composition consisting of only A and B. All documents cited herein are incorporated by reference in their entirety for all purposes.

[0026] Two-dimensional (2D) materials have rapidly attracted attention for a wide range of energy storage applications due to their unique physical and chemical properties. 2D materials exhibit features such as high porosity, increased specific surface area, good crystallinity, high electrical conductivity, and abundant and tunable surface active sites. The aforementioned properties make 2D materials suitable as hosts for energy storage systems. In addition, 2D materials have advantages over 3D materials. Also, according to the literature, the only way to fabricate 2D materials is by etching layered solids.

[0027] Provided herein is a novel method for the mass production of 1 Da materials by a bottom-up approach, among other things, for Li-S batteries and other batteries, e.g., chalcogen-containing batteries. Such materials are synthesized for the first time near room temperature using non-layered precursors, and offer improved properties, especially tunable electrical conductivity and functional groups. The unique properties of these materials are notable, especially for the Li-S system, in that:

[0028] The combination of insulating and conductive properties of sulfur improves the overall utilization of the sulfur cathode.

[0029] The abundant functional groups on the surface, i.e., hydroxyl and oxygen groups, coupled with the tunable oxidation states and defects of Ti (or other transition metals), can provide affinity to bind with lithium polysulfides and suppress the shuttle effect. Furthermore, the functional groups can form complexes such as thiosulfates and polythionates, improving the binding ability with lithium polysulfides.

[0030] The free-standing flexible film of the disclosed 1 Da material mixed with sulfur can buffer volume changes during cycling while providing good flexibility.

[0031] The conductive sheet surface with tunable functional groups can also impart catalytic properties, further enhancing the conversion rate.

[0032] To explore the effect of 1 Da in extending the cycle life of the lithium-sulfur system, we tested the behavior of 1 Da in a coin cell configuration. Figure 1A shows the results of the 1 Da charge-discharge test at 1.8 to 2.6 V (vs. Li / Li + ) range, 0.1 mV s -1Figure 1B shows typical cyclic voltammetry (CV) curves at scan rates of 1000, 1200, and 1050 mAhg at 0.1, 0.2, and 0.5 C rates, respectively. The CV curves show two sharp and distinct cathodic peaks and one anodic peak. The first cathodic peak at 2.3 V is attributed to S reduction (S8) to long-chain lithium polysulfides (LiPs), and the second peak is associated with the subsequent reduction of LiPs to Li2S2 / Li2S. The peak shift after the first anodic peak is attributed to the nucleation / reorganization of LiP as it reprecipitates to S8. Figure 1B shows a typical discharge plateau, which is consistent with the CV results. The TiCO / S composite electrode discharged 1300, 1200, and 1050 mAhg at 0.1, 0.2, and 0.5 C rates, respectively. -1 Such a high capacity may be related to the electrical conductivity of TiCO and its surface active sites that can bind LiP. To evaluate the long-term stability of the cathode, -2 The cells were cycled at 0.5C with an S loading of 0.01 μm. According to Figure 1C, the initial capacity of the cells was ~1300 mAhg -1 After the first 5 cycles, it was ~1000mAhg -1 This initial capacity drop is associated with two conditioning cycles at low rates of 0.1C and 0.2C. The composite reaches a capacity of ~1000mAhg after about 300 cycles. -1 The cathode showed a capacity of 1 Da and a retention rate of about 100%. The capacity decayed after 300 cycles. These values ​​are impressive considering that the cathode was made by blending 1 Da flakes and commercial S powder into a slurry using a mortar and pestle.

[0033] experiment To evaluate the performance of 1Das as a sulfur host in Li-S batteries, 1Da / S cathodes were fabricated by a slurry-based method. Briefly, a slurry was prepared by mixing 35 wt% vacuum-dried 1Das, 35 wt% sulfur S, 20 wt% conductive carbon (Alfa Aesar, Super P), and 10 wt% battery-grade PVDF binder (MTI Corp., USA). The materials were hand-ground in a mortar and pestle until homogeneous. N-methyl-2-pyrrolidone (TCI, USA) was then added slowly (~25 min) until the visible viscosity and homogeneity of the slurry was as required. The slurry was then poured onto aluminum foil with a doctor blade (MTI, USA) at a thickness of 20 μm. After pouring, the slurry was kept under a closed fume hood for 2 h before being transferred to a vacuum oven and dried at 50 °C for 12 h.

[0034] The dried 1 Da / S cathode was cut into a disk shape using a hole punch (diameter 11 mm). The electrode was then weighed and transferred to an Ar-filled glove box (MBraun Lab star, O2<1ppm, H2O<1ppm). A CR2032 (MTI Corporation and Xiamen TMAX Battery Equipment) coin-type Li-S cell was assembled using the 1 Da / S cathode, a 15.6 mm diameter, 450 μm thick Li disk anode (Xiamen TMAX Battery Equipment), a 3-ply separator (Celgard 2325), a stainless steel spring and two spacers, and electrolyte. The electrolyte was 1M LiTFSi in a 1:1 volumetric mixture of 1,2-dimethoxyethane and 1,3-dioxolane, plus 1 wt% LiNO3, purchased from TMAX Battery Equipment, China, and contained traces of oxygen and moisture (H2O<6ppm, O2<1ppm). The assembled coin cells were rested at open circuit potential for 10 h before electrochemical experiments were performed at room temperature. Cyclic voltammetry was performed using a potentiostat (Biologic VMP3) to measure the Li / Li + , voltage between 1.8 and 2.6 V is 0.1 mV.s -1Long-term cycling stability tests were performed using a battery cycler (Neware BTS 4000) at different C rates (where 1C = 1675 mAh.g) between voltages of 1.8 and 2.6 V. -1 The Li-S cells were conditioned at 0.1 C for the first cycle, 0.2 C for the second cycle, and 0.5 C thereafter.

[0035] Figure 2 shows the electrochemical cycling of two TiC-based 1Das sulfur composites, which account for 70% of the cathode, with an areal loading of 1mg.cm^-2. As shown, the TiC / S composite reacted at 50°C for 5 days maintained its capacity. Thus, the TiC / S composite stored at 50°C for 5 days maintained its capacity for a higher number of cycles than the TiC / S composite stored at 80°C for 3 days. This is shown in both the left and right panels of Figure 2.

[0036] Figure 3 shows the cyclic voltammetry of 50C 5 days 1 Das with 0.7 mg sulfur added at various cycle rates.

[0037] Figure 4 shows an exemplary rate study of 1Das 0.7 mg from TiC at 50C 5 days. As shown, the disclosed material exhibited good rate capability at 1C versus 0.1C, 0.2C, and 0.5C, demonstrating the performance of the disclosed material.

[0038] Figure 5 shows the capacity contribution of 1 Da TiC material prepared at 50 degrees C for 5 days. As shown, 1 Da TiC exhibits low capacity contribution in the voltage window of 1.8 V to 2.6 V, which is the voltage window for lithium sulfur. The specific capacity of TiC 1 Da is 5 mAh / g, decreasing to 1.4 mAh / g at the second cycle.

[0039] Figure 6 shows a visual polysulfide test to observe the interaction with TiC 1Das. Compared to carbon black, 1Das removed more polysulfides as seen in the photo after 7 days. Two concentrations were made: 0.5 mM and 2 mM.

[0040] Figure 7 shows the XPS of the cycled cathode with TiC 1Das and sulfur after use. The appearance of polythionate peaks in the S2p spectrum elucidates the electrocatalytic mechanism of polysulfide absorbance of TiC 1Das. Furthermore, the appearance of lithium sulfur peaks in both the S2p and Ti2p spectra reveals the mechanism of Lewis acid-base binding.

[0041] Figure 8 compares pristine and used TiC 1Das, showing a shift in the Ti-O peaks (dark blue and pink). Without being bound to any particular theory, this further suggests an interaction between the polysulfides and titanium in TiC 1Das, since a change in the coordination number of titanium causes such a shift in the bond energy.

[0042] Figure 9 shows exemplary SEMs of TiC 1Das at various sonication and reaction temperatures. The sample sonicated at 80°C for 3 days and 2 hours showed a more fibrous surface compared to the sample sonicated at 50°C for 5 days and 2 hours.

[0043] FIG. 10 is an exemplary SEM of a cathode according to the present disclosure.

[0044] Figure 11 shows SEM images of the top (left) and bottom (right) surfaces of a used 1Das(TiC) cathode. As can be seen, the cathode maintains its morphology even after use.

[0045] Figure 12 is an SEM photograph (cross section) of a 1Das(TiC) cathode after use. As can be seen, the cathode maintains its morphology even after use.

[0046] FIG. 13 shows the performance of TiB 1Das material prepared for Li-S cells with 1 mg sulfur added at 80° C for 3 days.

[0047] Figure 14 is an SEM of 1 Das TiB prepared at 80 degrees C for 3 days.

[0048] manufacturing The following disclosure is illustrative and does not limit the scope of the disclosure or the appended claims.

[0049] Exemplary TiC 1Das Briefly, commercially available titanium carbide (Alfa Aesar 200 mesh) or titanium boride is mixed with tetramethylammonium hydroxide (TMAOH) from Alfa Aesar at a ratio of 1g per 10ml of TMAOH. This is reacted at 50C for 5 days or at 80C for 3 days with vigorous stirring. The product is then washed 5 times with absolute ethanol. 1Das of the resulting pellet is extracted by mixing with pure water and colloidalized. Unreacted titanium carbide is removed at this stage through a centrifuge. 1Das of colloid is then added and stirred with 5M lithium chloride (Alfa Aesar) for 24 hours. The resulting mixture is washed with pure water and centrifuged until the pH is neutral. The colloid is sonicated for 2 hours while keeping the temperature below 15C with argon (Airgas) bubbling. The colloid is then vacuum filtered and freeze-dried to form a 1Das film.

[0050] Preparation of electrodes for Li-S batteries The composite electrodes were fabricated by a typical slurry method. For example, for 100 mg of slurry, 35 mg of freeze-dried TiC 1Das was combined with 35 mg of sulfur (Alfa Aesar) to form a sulfur composite. Then, 20 mg of conductive carbon SuperP (Alfa Aesar) was added to 10 mg of battery grade polyvinylidene fluoride (PVDF) binder (MTI). The powder was drop-mixed with N-methyl-2-pyrrolidone (NMP) (TCI), typically about 400 microliters of zirconia mixing balls placed in a polypropylene Frac-Tec cup. The slurry was mixed in a Frac-Tec planetary mixer at 2000 rpm for a total of 8 minutes, at which point the slurry reached the desired viscosity. The resulting slurry was blade cast onto aluminum foil. After casting, the slurry was transferred to a vacuum oven and dried at 50 °C for 12 hours. The electrode was then freeze-dried again to remove the water and kept under vacuum for 24 hours.

[0051] Coin cell manufacturing The dried cast electrodes were punched into 11 mm diameter coin cell cathodes. They were weighed and transferred to the antechamber of a glovebox (Mbraun, Labstar, O2<1ppm, H2O<1pmm) filled with argon (Airgas). The electrodes were assembled into CR2032 (MTI and Xiamen TMAX Battery Equipment, China) coin cells. The assembly also included a 13 mm diameter disk of 750 μm thick lithium metal foil (Alfa Aesar) and a 19 mm Celgard 2325 separator. The lithium metal foil was placed on a stainless steel spacer and pressure was provided by a single stainless steel spring. The electrolyte used in the cells was 1 M lithium bis(trifluoromethanesulfonyl)imide (LiTFSi) in a 1:1 volumetric mixture of 1,2-dimethoxyethane and 1,3-dioxolane, with 1 wt % lithium nitrate (LiNO3) and a water content of 1 ppm. The amount of electrolyte is 20 μL.mg electrolyte / sulfur ratio. -1Galvanostatic tests were performed on a multichannel MACCOR cycler (4000 series) and a Neware BTS 4000 battery cycler. Cyclic stability tests consisted of two conditioning cycles at 0.1C and two conditioning cycles at 0.2C (1C=1672mAh.g -1 ) at room temperature in the voltage range of 1.8V to 2.6V vs Li / Li + Cyclic voltammetry was performed using a potentiostat (VMP3, Biologic, France) in the voltage range of 1.8 V to 2.6 V vs. Li / Li. + , scan rate 0.1mV.s -1 ~0.5mV.s -1 So I went.

[0052] Material properties X-ray diffraction was performed using a diffractometer (Miniflex, Rigaku, Japan) with Cu-Kα radiation (40 kV, 15 mA) to measure the properties of 1 Das in the 2θ range of 5°–60°. X-ray photoelectron spectroscopy was performed using a Physical Electronics, VersaProbe 5000 with an Al-Kα source at 1486.2 eV. For post-use cycled cathodes, an argon gun was used to remove electrolyte surface species. Scanning electron microscopy was used to evaluate the morphology of the samples, which was performed using a Zeiss Supra VP50 field emission scanning electron microscope equipped with an Everhart-Thornley secondary electron detector and an Oxford UltiMax 40 mm energy dispersive spectrometer equipped with a silicon drift detector for elemental analysis. The weight percentage of sulfur was measured using a 5000 nm TEM microscope at 37 °C for 1 min in ultra-high purity nitrogen (Airgas). -1 This was confirmed from the composite slurry using a Setalam Setline STA thermogravimetric analyzer.

[0053] Further manufacturing techniques In one example synthesis process, the precursor powders are soaked in 25 wt% TMAH in a polyethylene jar and heated on a hot plate at temperatures ranging from room temperature (RT) to 85 °C for periods ranging from 24 hours to 1 week. (Periods longer than 1 week can also be used, e.g., 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, or 15 days, and all intermediate ranges and values ​​can also be used). After reaction with TMAH, a dark black precipitate (except for Ti2SbP, TiB2, and TiO2) is obtained, collected, washed with ethanol, shaken, and centrifuged at 3500 rpm for multiple cycles until a clear supernatant is obtained. Once the supernatant is clear, 30 mL of deionized water is added to the washes and shaken for 5 minutes. After centrifugation at 3500 rpm for 0.5 hours without sonication, a stable colloidal suspension is obtained. The unreacted powder is precipitated. The colloid is vacuum filtered to obtain the FF.

[0054] In some cases, an additional washing step with LiCl solution was performed and the resulting flakes were characterized. 5M LiCl solution was added to the black colloidal suspension obtained above. This resulted in deaggregation. The precipitate was shaken, centrifuged at 5000 rpm for three cycles, and washed with deionized water. The LiCl / deionized water washes were repeated until the pH was about 7. The washed precipitate was then sonicated in a cold bath under flowing Ar for 1 h, shaken for 5 min, and centrifuged at 3500 rpm for 10 min. The colloidal suspension was filtered to obtain the FF. The FF was dried overnight in a vacuum chamber before further characterization.

[0055] The black slurry produced from the reaction of TMAH and TiC was centrifuged (5000 rpm, 5 min) as is without adding any solvent, the supernatant was decanted, and the precipitate was suspended in 20 mL of pure water, shaken for 5 min, and then centrifuged at 3500 rpm for 30 min in few cases. The produced black colloidal suspension was used for XRD (not shown) and TEM examination.

[0056] Without being bound to a particular theory, the disclosed materials can be produced by contacting a mono-, bi-, ternary, or higher carbide, nitride, boride, phosphide, aluminide, or silicide, or titanium metal with a quaternary ammonium salt and / or base, where the mono-, bi-, ternary, or higher carbide, nitride, boride, phosphide, aluminide, or silicide, or titanium metal is selectively water insoluble, and the water insoluble binary, ternary, or higher carbide, nitride, boride, phosphide, aluminide, or silicide selectively comprises a transition metal, and the transition metal selectively comprises titanium, under conditions sufficient to produce a nanofilamentary (and / or sub-nanofilamentary) product, e.g., 1 Da, which can self-assemble into two-dimensional flakes.

[0057] Exemplary carbides include, for example, titanium carbide, zirconium carbide, hafnium carbide, vanadium carbide, niobium carbide, tantalum carbide, chromium carbide, molybdenum carbide, tungsten carbide, iron carbide, etc. Examples of nitrides include, for example, aluminum nitride, boron nitride, calcium nitride, cerium nitride, europium nitride, gallium nitride, indium nitride, lanthanum nitride, lithium nitride, magnesium nitride, niobium nitride, silicon nitride, strontium nitride, tantalum nitride, titanium nitride, vanadium nitride, zinc nitride, zirconium nitride, etc.

[0058] Examples of borides include aluminum diboride, aluminum diboride, aluminum magnesium boride, barium boride, calcium hexaboride, cerium hexaboride, chromium (III) boride, cobalt boride, nickel diboride, erbium hexaboride, erbium tetraboride, hafnium diboride, iron boride, iron tetraboride, lanthanum hexaboride, magnesium diboride, nickel boride, niobium diboride, osmium boride, plutonium boride, rhenium diboride, ruthenium boride, samarium hexaboride, scandium diboride, silicon boride, strontium hexaboride, tantalum boride, titanium diboride, trinickel boride, tungsten boride, uranium diboride, yttrium boride, and zirconium diboride.

[0059] Examples of phosphides include, for example, aluminum gallium phosphide, aluminum gallium phosphide, aluminum phosphide, bismuth phosphide, boron phosphide, cadmium phosphide, calcium monophosphide, calcium phosphide, carbon monophosphide, cobalt (II) phosphide, copper (I) phosphide, dysprosium phosphide, erbium phosphide, europium (III) phosphide, ferrophosphorus phosphide, gadolinium phosphide, gallium arsenide phosphide, indium arsenide gallium antimony phosphide, gallium phosphide, holmium phosphide, indium arsenide gallium phosphide, indium gallium phosphide, indium phosphide, indium phosphide, gallium phosphide, holmium phosphide, indium arsenide gallium phosphide, indium phosphide, gall ... Examples of phosphide include iron phosphide, lanthanum phosphide, lithium phosphide, lutetium phosphide, neodymium phosphide, niobium phosphide, phosphorus carbide, phosphorus chloride, phosphorus silicide, plutonium phosphide, praseodymium phosphide, samarium phosphide, scandium phosphide, sodium phosphide, plutonium phosphide, praseodymium phosphide, praseodymium phosphide, samarium phosphide, scandium phosphide, sodium phosphide, strontium phosphide, tellurium phosphide, terbium phosphide, thulium phosphide, titanium(III) phosphide, uranium monophosphide, ytterbium phosphide, yttrium phosphide, zinc diphosphide, cadmium zinc arsenide phosphide, and zinc phosphide.

[0060] Examples of the aluminides include magnesium aluminide, titanium aluminide, iron aluminide, nickel aluminide, and the like.

[0061] Examples of silicides include nickel silicide, sodium silicide, magnesium silicide, platinum silicide, titanium silicide, tungsten silicide, and molybdenum silicide.

[0062] Without being bound to any particular theory or embodiment, mono-, bi-, or ternary or more carbides, nitrides, borides, phosphides, aluminides, or silicides of titanium are particularly preferred. Similarly, titanium sponge is believed to be a particularly preferred form of titanium metal for use in the disclosed technology. For example, titanium sponge can be contacted with a quaternary ammonium salt as described herein to produce a nanofilamentary (or sub-nanofilamentary) product as described herein.

[0063] The manufacturing conditions can consist of a temperature of 0 to 100°C, 200°C, or 300°C for about 0.5 hours to about 1, 2, 3, 4, or 5 weeks. The temperature can be constant during the exposure time, but can also be varied, e.g., increased and / or decreased. The temperature can be, for example, about 0 to about 300°C, about 5 to about 95°C, about 10 to about 90°C, about 15 to about 85°C, about 20 to about 80°C, about 25 to about 75°C, about 30 to about 70°C, about 35 to about 65°C, about 40 to about 60°C, about 45 to about 55°C, or about 50°C. 100 to 200°C is also suitable. The temperature can be varied during the exposure (e.g., exposure to a first temperature followed by exposure to a second temperature), but this is not a requirement. The exposure can be, for example, according to a preprogrammed schedule that sets the temperature and / or exposure time. The exposure temperature can be, for example, 25, about 30, about 35, about 40, about 45, about 50, about 55, about 60, about 65, about 70, about 75, about 80, about 90, about 95, or about 100°C.

[0064] In some embodiments, the conditions include a temperature of about 20 to about 300°C and exposure for about 0.5 hours to about 2, 3, 4, or 5 weeks. The conditions include a temperature of about 100 to about 200°C and exposure for about 1 hour to about 1 week. The temperature may be constant during the exposure time, but may also be varied, for example, increased and / or decreased. The temperature may be, for example, about 100 to about 200°C, about 105 to about 195°C, about 100 to about 190°C, about 115 to about 185°C, about 120 to about 180°C, about 25 to about 175°C, about 130 to about 170°C, about 135 to about 165°C, about 140 to about 160°C, about 145 to about 155°C, or about 150°C. The temperature can be changed during the exposure (eg, exposure to a first temperature followed by exposure to a second temperature), although this is not a requirement.

[0065] The exposure can be performed according to a preprogrammed schedule that sets, for example, the temperature and / or duration of the exposure. The exposure temperature can be, for example, about 125, about 130, about 135, about 140, about 145, about 150, about 155, about 160, about 165, about 170, about 175, about 180, about 190, about 195. The method can be performed in a closed system, for example, a pressure vessel. The pressure can be atmospheric, but can also be less than atmospheric, or greater than atmospheric, for example, greater than 1 atmosphere (101.325 kPa) to about 10 atmospheres (1013.250 kPa).

[0066] The exposure period (which may be referred to as the "reaction time") may be, for example, from about 1 hour to about 7 days, from about 5 hours to about 6 days, from about 15 hours to about 5 days, from about 20 hours to about 4 days, from about 24 hours to about 3 days, or from about 2 days. However, as some examples, the exposure may be from 12 hours to about 72 hours, from about 15 hours to about 70 hours, from about 18 hours to about 64 hours, from about 24 hours to about 60 hours, from about 30 hours to about 55 hours, from about 33 hours to about 52 hours, from about 37 hours to about 48 hours, from about 40 hours to about 45 hours, and all intermediate values ​​and partial combinations of ranges.

[0067] The preparation can include, for example, contacting a mono-, bi-, ternary, or more boride (which can include Ti) with a quaternary ammonium salt and / or base to produce a product, which can be nanofilamentary and / or sub-nanofilamentary. The binary boride can include one or more titanium borides. The quaternary ammonium salt and / or base can include ammonium hydroxide, ammonium halide, or any combination thereof.

[0068] The quaternary ammonium hydroxide can include, for example, tetramethylammonium hydroxide (TMAOH), tetraethylammonium hydroxide (TEAOH), tetrapropylammonium hydroxide (TPAOH), tetrabutylammonium hydroxide (TBAOH), ammonium hydroxide (NH4OH), their amine derivatives, or any combination thereof. The quaternary ammonium salt can include quaternary ammonium chloride, quaternary ammonium bromide, quaternary ammonium iodide, quaternary ammonium fluoride, or any combination thereof. It should be understood that either or both of the quaternary ammonium salt and the quaternary ammonium base can be used.

[0069] The manufacturing process may further include filtering the product. The manufacturing process may also include washing the product with metal salts and / or other water-soluble metal compounds.

[0070] The metal salt can be, for example, a metal halide salt, such as a Li halide, a Na halide, a K halide, a Rb halide, a Cs halide, a Fr halide, a Be halide, a Mg halide, a Ca halide, a Sr halide, a Ba halide, a Ra halide, a Mn halide, a Fe halide, a Ni halide, a Co halide, a Cu halide, a Zn halide, a Mo halide, a Nb halide, a W halide, or any combination thereof.

[0071] The article may also be washed with a metal salt and / or a water-soluble metal compound. The metal salt may optionally include a metal sulfate, nitrate, chromate, acetate, carbonate, permanganate, metal hydroxide, or any combination thereof. The metal in the salt may be essentially any metal from the periodic table.

[0072] However, as some non-limiting examples, the metal in the metal salt can be Li, Na, K, Cs, Mg, Ca, Cr, Mn, Fe, Co, Ni, Cu, Zn, Nb, Mo, Cd, Ta, or W, or any combination thereof. The metal salt can be, for example, LiCl, KCl, NaCl, LiF, KF, NaF, LiOH, KOH, NaOH, or any combination thereof. The metal salt can also be, for example, CrCl3, MnCl2, FeCl2, FeCl3, CoCl2, NiCl2, MoCl5, FeSO4, (NH4)2Fe(SO4)2, CuCl2, CuCl, ZnCl2, or any combination thereof.

[0073] The article can be, for example, a nanofilament (and / or sub-nanofilament) article that exhibits an XRD pattern that exhibits reduced (104) and (105) peaks at about 38° and about 55° two-theta (2θ) when compared to the XRD pattern of nano or bulk anatase. As described elsewhere herein, the disclosed nanofilaments and / or sub-nanofilaments can, in some embodiments, exhibit Raman spectra that are similar to those of bulk anatase, but that can differ from bulk anatase in terms of their XRD spectra, as described herein.

[0074] Aspects The following aspects are illustrative, and do not limit the scope of the disclosure or the appended claims.

[0075] Aspect 1. A composition comprising a chalcogen, 1Das, and optionally a conductive material. The composition can also include a binder, suitable binders being described elsewhere herein.

[0076] Embodiment 2. The composition of embodiment 1, wherein the chalcogen comprises sulfur.

[0077] Aspect 3. The composition of aspect 2, wherein the composition is 1 cm 2 about 0.05 to about 150 mg of chalcogen per cm, for example about 1 to about 20 mg / cm 2 The composition comprises sulfur (or other chalcogen) present at a loading of 0.1 to 0.5.

[0078] Aspect 4. The composition according to any one of Aspects 1 to 3, wherein said 1 Da comprises titanium oxide and / or titanium oxide carbide.

[0079] Embodiment 5. An electrode, the electrode comprising the composition of any one of embodiments 1-4, the electrode optionally being configured as a cathode.

[0080] Example 6. The electrode of example 5, wherein the electrode comprises a ceramic matrix composite (CMC), polyvinylidene fluoride (PVDF), polyacrylic acid (PAA), polyvinyl alcohol (PVA), polyethylene glycol (PEG), sodium carboxymethyl chitosan (CCTS), sodium alginate (SA), styrene butadiene rubber (SBR), or any combination thereof.

[0081] The electrodes may also include a conductive material, such as a carbonaceous material. The conductive material may be, for example, MXene, metal or metalloid particles, etc. Metal particles are believed to be particularly suitable, as are MXene, graphene, carbon nanotubes (single-walled and / or multi-walled), etc.

[0082] The conductive material can include one type of component (eg, one type of carbon nanotube), but can also include multiple components (eg, carbon nanotubes and MXene).

[0083] Aspect 7. The electrode of aspect 5, wherein: (a) the electrode has a capacity of about 300 to 1675 mAhg -1 or (b) said electrode exhibits substantially the same capacity for at least about 10 cycles, or wherein said electrode exhibits both (a) and (b).

[0084] The electrode can include chalcogen (e.g., sulfur) present in an amount of about 30 to about 99% by weight of the electrode, for example, about 30 to about 99% by weight, about 35 to about 95% by weight, about 40 to about 90% by weight, about 45 to about 85% by weight, about 50 to about 80% by weight, about 55 to about 75% by weight, about 60 to about 70% by weight, or even about 65% by weight.

[0085] The chalcogen (e.g., sulfur) loading can also be defined as weight per area, i.e., cm 2 It can also be described in mg (chalcogen) per (electrode). In some embodiments, the chalcogen is about 0.05 to about 150 mg / cm 2 , about 1~20mg / cm 2 , or about 2 to about 19 mg / cm 2 , or about 3 to about 18 mg / cm 2 , or about 4 to about 17 mg / cm 2 , or about 5 to about 16 mg / cm 2 , or about 6 to about 15 mg / cm 2 , or about 7 to about 14 mg / cm 2 , or about 8 to about 13 mg / cm 2 , or about 9 to about 12 mg / cm 2 , or further about 10 to about 11 mg / cm 2 It exists in.

[0086] Example 8. An energy cell, comprising a first electrode according to any one of Examples 5 to 7.

[0087] Example 9. The energy cell of example 8, wherein the energy cell comprises a second electrode, the second electrode comprising an alkali metal, an alkaline metal, a transition metal, graphite, an alloy, silicon, graphene, or any combination thereof.

[0088] Example 10. The energy cell of example 9, wherein the second electrode comprises at least one of lithium, sodium, potassium, magnesium, calcium, zinc, copper, titanium, nickel, cobalt, iron, and aluminum.

[0089] Embodiment 11. The energy cell of any one of embodiments 9-10, wherein the first electrode is characterized as a cathode and the second electrode is characterized as an anode.

[0090] Aspect 12. The energy cell of any one of aspects 8 to 11, further comprising an electrolyte, the electrolyte optionally comprising an ether and / or a carbonate. Other electrolytes, such as electrolytes comprising alkali metal ions and / or halide ions, may also be used.

[0091] Example 13. The energy cell of example 12, further comprising a separator, the separator optionally comprising one or more of polypropylene, polyethylene, fiberglass, or porous rubber.

[0092] Example 14. A method, the method comprising discharging an energy cell according to any one of Examples 8-13, or charging an energy cell according to any one of Examples 8-13.

[0093] Aspect 15. An electric device comprising the energy cell according to any one of aspects 8 to 13.

[0094] A method comprising forming an admixture comprising a chalcogen, 1Da, and optionally a conductive material. Examples of chalcogens include, for example, oxygen, sulfur, selenium, tellurium, and polonium, with sulfur being believed to be particularly suitable.

[0095] The blend may also include a binder, such as a polymer. Examples of polymers include, for example, PVDF (polyvinylidene fluoride) and SBR (styrene butadiene rubber). The binder may include one component (e.g., SBR), but may also include multiple components (e.g., SBR and PVDF).

[0096] Aspect 17. The method of aspect 17, wherein the conductive material comprises a carbonaceous material, and the conductive material can be, for example, MXene, metal or metalloid particles, etc. Metal particles are believed to be particularly suitable, as are MXene, graphene, carbon nanotubes (single-walled and / or multi-walled), etc. The conductive material can include one type of component (e.g., one type of carbon nanotube), but can also include multiple components (e.g., carbon nanotubes and MXene).

[0097] Aspect 18. The method according to any one of aspects 16 to 17, wherein said 1 Da comprises titanium oxide and / or titanium oxide carbide.

[0098] EMBODIMENT 19. The method of any one of embodiments 16-18, wherein the chalcogen comprises sulfur. The chalcogen (e.g., sulfur) can be present in the admixture at about 30% to 99% by weight, including all intermediate values ​​and subranges. For example, the chalcogen can be present at 30%, 35%, 40%, 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85%, 90%, 95%, or 99% by weight, and all intermediate values ​​and subranges. As some examples, the chalcogen can be present at about 30 to about 99% by weight, about 35 to about 95% by weight, about 40 to about 90% by weight, about 45 to about 85% by weight, about 50 to about 80% by weight, about 55 to about 75% by weight, about 60 to about 70% by weight, or about 65% by weight.

[0099] Aspect 20. The method of any one of aspects 16-19, further comprising forming an electrode from the admixture. The electrode can be used, for example, as a cathode. Such an electrode can be an electrode according to the present disclosure, for example, an electrode according to any one of aspects 5-7.

Claims

1. A composition comprising a chalcogen, 1 Da, and optionally a conductive material.

2. The composition of claim 1 , wherein the chalcogen comprises sulfur.

3. 3. The composition of claim 2, wherein the composition is 1 cm ２ From about 0.05 to about 150 mg chalcogen per cm ２ 1. A composition comprising a chalcogen present at a loading of about 1 to about 20 mg chalcogen per mol, said chalcogen optionally comprising sulfur.

4. The composition according to any one of claims 1 to 3, wherein the 1Da comprises titanium oxide and / or titanium oxide carbide.

5. 4. An electrode, comprising the composition according to any one of claims 1 to 3, said electrode optionally configured as a cathode.

6. 6. The electrode of claim 5, wherein the electrode comprises ceramic matrix composite (CMC), styrene butadiene rubber (SBR), polyvinylidene fluoride (PVDF), polyacrylic acid (PAA), polyvinyl alcohol (PVA), polyethylene glycol (PEG), sodium carboxymethyl chitosan (CCTS), sodium alginate (SA), or any combination thereof.

7. 6. The electrode of claim 5, wherein: (a) the electrode has a capacity of about 300 to 1675 mAhg －１ or (b) said electrode exhibits substantially the same capacity for at least about 10 cycles, or (a) and (b) both.

8. An energy cell, the energy cell comprising a first electrode according to claim 5 .

9. 10. The energy cell of claim 8, wherein the energy cell comprises a second electrode, the second electrode comprising an alkali metal, an alkaline metal, a transition metal, graphite, an alloy, silicon, graphene, or any combination thereof.

10. 10. The energy cell of claim 9, wherein the second electrode comprises at least one of lithium, sodium, potassium, magnesium, calcium, zinc, copper, titanium, nickel, cobalt, iron, and aluminum.

11. 10. The energy cell of claim 9, wherein the first electrode is characterized as a cathode and the second electrode is characterized as an anode.

12. 10. The energy cell of claim 8, further comprising an electrolyte, said electrolyte optionally comprising an ether and / or a carbonate.

13. 13. The energy cell of claim 12, further comprising a separator, said separator optionally comprising one or more of polypropylene, polyethylene, fiberglass, or porous rubber.

14. 10. A method, the method comprising discharging an energy cell according to claim 8 or charging an energy cell according to claim 8.

15. An electrical device comprising the energy cell of claim 8.

16. 1. A method comprising: The method includes forming an admixture including a chalcogen, 1 Da, and, optionally, a conductive material.

17. The method of claim 17 , wherein the conductive material comprises a carbonaceous material.

18. The method according to any one of claims 16 to 17, wherein the 1Da comprises titanium oxide and / or titanium oxide carbide.

19. The method of any one of claims 16 to 17, wherein the chalcogen comprises sulfur.

20. The method of any one of claims 16 to 17, further comprising forming an electrode from the admixture.

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