JP2024507122A - Bottom-up and scalable synthesis of oxide-based subnano and nanofilaments, nanofilament-based two-dimensional flakes and mesoporous powders - Google Patents

Abstract

A bottom-up approach provides a case in which binary and ternary titanium carbides, nitrides, borides, phosphides, aluminides, and silicides are immersed in quaternary ammonium solutions at moderate temperatures. In some cases, nanofilaments can be converted into nanofilaments that self-assemble into 2D flakes. The resulting flakes result in a C-containing anatase-based layer whose cross section is composed of nanofilaments, some of which are several microns long. Electrodes made from these materials have shown good performance in energy systems. This material also reduces the viability of some cancer cells. Also provided are mesoporous materials, devices, and related methods. [Selection diagram] None

Description

Related Applications This application is filed in U.S. Patent Application No. 63/148,348 (filed on February 11, 2021), U.S. Patent Application No. 63/167,197 (filed on March 29, 2021), and U.S. Patent Application No. No. 63/171,293, filed April 6, 2021, and U.S. Patent Application No. 63/275,631, filed November 4, 2021. The aforementioned applications are incorporated herein in their entirety for all purposes.

TECHNICAL FIELD The present disclosure relates to the field of 1D and 2D materials, and the field of metal oxide-based nanomaterials.

One-dimensional (1D) and two-dimensional (2D) materials have advantages over their 3D counterparts. Historically, the starting point for the synthesis of 2D materials in bulk has been mostly layered solids such as clays, graphites, or more recently MAX phases. The idea of synthesizing 2D solids in bulk from non-layered solids has been considered difficult/impossible. Therefore, there is a need for 2D solids, especially such solids synthesized in bulk from non-layered solids. Most 1D nanofilaments are not stable in water. Therefore, there is a need for 1D solids, especially solids that are stable in water.

As an example of the disclosed technology, we used a bottom-up approach to synthesize 10 binary and ternary titanium carbides, nitrides, borides, phosphides, and silicides at temperatures ranging from 25 to 85 °C, for example. It was converted into 2D flakes by immersion in tetramethylammonium hydroxide (TMAH) solution. Based on X-ray diffraction, density functional theory, X-ray photoelectron, electron energy loss, Raman, X-ray absorption near-edge structure spectroscopy, transmission and scanning electron microscopy images, and selected area diffraction, the obtained thin sections were found to be C-containing anatase. We conclude that the base layer, the cross-section of which (in some embodiments) consists of ≈6x10 Å ² nanofilaments, some of which are several microns long. Electrodes made from some of these films showed good performance in lithium-ion and lithium-sulfur systems. These materials also show potential for biomedical applications as they reduce the viability of cancer cells. Synthesizing two-dimensional (2D) materials consisting of 1D bodies at near-room temperature conditions using non-layered and inexpensive precursors (e.g. TiC, TiB ₂ , TiN, etc.) is a paradigm shift and is an exciting topic for research and application. There is no doubt that it will open up new and exciting avenues.

To meet the long-standing needs described, the present disclosure provides compositions that include a plurality of metal oxide (e.g., metal oxide-based) nanofilaments and/or sub-nanofilaments and optionally an amount of carbon. . (As described herein, nanofilaments can include titanium.) Examples of such compositions include "Bottom-up, scalable synthesis of anatase nanofilament-based two-dimensional titanium carbo- oxide flakes", Badr et al., Materials Today (2021), incorporated herein by reference in its entirety for all purposes.

Also provided is a device comprising a composition according to the present disclosure, eg, a composition according to any one of embodiments 1-16.

A method is further disclosed comprising operating a device according to the present disclosure, such as a device according to aspect 16.

It also includes contacting mono, binary, ternary or more carbides, nitrides, borides, phosphides, aluminides, or silicides, or titanium metal with quaternary ammonium salts and/or bases. and said mono, binary, ternary, or more carbide, nitride, boride, phosphide, aluminide, or silicide, or titanium metal is optionally water-insoluble, and said water-insoluble binary The elementary, ternary, or higher carbide, nitride, boride, phosphide, aluminide, or silicide optionally comprises a transition metal, said transition metal optionally comprising titanium, and said contacting step , a method comprising a contacting step carried out under conditions sufficient to produce a nanofilamentary product is disclosed.

It also includes contacting the particulate TiO ₂ with a quaternary ammonium salt, said contacting being conducted under conditions sufficient to produce an anatase nanoparticle product, said nanoparticle product comprising: Optionally, methods are also disclosed in which at least some of the nanoparticles have a diameter of about 2 nm to about 1000 nm, optionally about 10 nm to about 100 nm.

Further, in accordance with the present disclosure there is provided a composition comprising a population of anatase nanoparticles produced, for example, according to one of embodiments 38-42.

Also disclosed is a method comprising replacing TiO ₂ with a population of anatase nanoparticles made according to the present disclosure, eg, according to any one of embodiments 38-42.

Also, the step of contacting mono, binary, ternary, or more carbides, nitrides, borides, phosphides, aluminides, or silicides, or titanium metal with quaternary ammonium salts and/or bases. and said mono, binary, ternary, or more carbide, nitride, boride, phosphide, aluminide, or silicide, or titanium metal is optionally water-insoluble, and said water-insoluble binary The elementary, ternary, or higher carbide, nitride, boride, phosphide, aluminide, or silicide optionally comprises a transition metal, said transition metal optionally comprising titanium, and said contacting step A method is disclosed comprising the step of contacting, optionally with shaking, and wherein the contacting step is performed under conditions sufficient to produce mesoporous particles.

Also, the step of contacting mono, binary, ternary, or more carbides, nitrides, borides, phosphides, aluminides, or silicides, or titanium metal with quaternary ammonium salts and/or bases. and said mono, binary, ternary, or more carbide, nitride, boride, phosphide, aluminide, or silicide, or titanium metal is optionally water-insoluble, and said water-insoluble binary The elementary, ternary, or higher carbide, nitride, boride, phosphide, aluminide, or silicide optionally comprises a transition metal, said transition metal optionally comprising titanium, and said contacting step A method is disclosed comprising the step of contacting, optionally with shaking, and wherein said contacting step is subsequently washed with at least one salt and conducted under conditions sufficient to produce mesoporous particles. Ru.

contacting a mono, binary, ternary, or more carbide, nitride, boride, phosphide, aluminide, or silicide, or titanium metal with a quaternary ammonium salt and/or a base, comprising: The mono, binary, ternary, or more carbide, nitride, boride, phosphide, aluminide, or silicide, or titanium metal is optionally water-insoluble, and the water-insoluble binary, or the ternary or higher carbide, nitride, boride, phosphide, aluminide, or silicide optionally comprises a transition metal, said transition metal optionally comprising titanium, and said contacting step optionally comprising titanium. Further disclosed is a method comprising the step of contacting with shaking, carried out at a temperature of about 50 to about 95° C., followed by washing with LiCl, resulting in mesoporous particles.

Also provided in accordance with the present disclosure are mesoporous particles made, for example, according to any one of embodiments 45-47.

Further, a composition comprising mesoporous particles, wherein the mesoporous particles include titanium, and wherein the mesoporous particles have an XRD pattern of about 38° and about 55° two theta (2θ) as compared to an XRD pattern of nano or bulk anatase. Compositions are provided that exhibit XRD patterns that exhibit reduced (104) and (105) peaks.

Also, a method comprising delivering a therapeutic agent to a subject, said therapeutic agent being comprised in a composition according to the present disclosure, e.g., according to any one of aspects 48-49. A method is provided.

Also, a method comprising delivering a therapeutic agent to a subject, said therapeutic agent being comprised in a composition according to the present disclosure, e.g., according to any one of aspects 48-49. A method is disclosed.

Furthermore, an electrode is provided, said electrode comprising a composition according to the present disclosure, eg, according to any one of aspects 48-49.

Also disclosed is a device, said device comprising a composition according to the present disclosure, eg, according to any one of aspects 48-49.

Also provided is a method, said method comprising operating an apparatus according to the present disclosure, eg, according to any one of aspects 52-53.

This patent or application file contains at least one color drawing/photograph. Color drawings/photocopies of this patent or patent application publication will be provided by the Office upon request and payment of the necessary fee.

In the drawings, which are not necessarily drawn to scale, like numerals may represent similar components in different figures. Similar numbers with different letter suffixes can represent different instances of similar components. The drawings generally illustrate, by way of example, and not by way of limitation, various aspects discussed herein. In the drawing:

Figures 1A-1D Fabrication process, scanning electron microscopy (SEM) micrographs, and density functional theory (DFT) structures. (FIG. 1A) Schematic diagram of the fabrication process, (FIG. 1B) Typical cross-sectional SEM micrograph of TiC-derived filtration film (FF). Note the undigested TiC particles in the lower right corner. The inset shows a photograph of a typical colloidal suspension. (FIG. 1C) Isometric side view of a four-layer Ti layer 2D anatase-based structure with TiO ₄ C ₆ chemistry that best fits the XRD and selected area diffraction (SAD) results. Blue, orange, red and black spheres represent Ti, 2- and 3-coordinated O, C, respectively. Vertical arrows on the left indicate approximate dimensions. (FIG. 1D) Top view of nanofilaments (NFS) growing in the [200] (top) and [110] (bottom) directions. The inset (Fig. 1D) compares the experimental LP (dashed line) and DFT predictions (solid line) as a function of the number of Ti layers. Our coordinate system is shown at the bottom left of c and d and is not the bulk anatase coordinate system. Figures 2A-2D Characterization of 2D materials. (FIG. 2A) Logarithmic scale XRD pattern of filtered vertically aligned Ti ₃ AlC ₂ -derived film in transmission mode. The inset shows the pattern of the horizontally oriented film. The 5°2θ peak is due to Kapton tape. The blue squares are the 2θ positions determined from the TEM-SAD pattern (Table 3). (FIG. 2B) Raman spectra of FFs obtained from the indicated precursors. All powders were heated at 50 °C for 3 days and washed with ethanol and water, except the top _TiB2 , which was treated at 80 °C for 2 days. All peaks belong to anatase. [15] (Figure 2C) Core loss electron energy loss spectroscopy (EELS) data measured from five particles. The graph shows the carbon-K edge at an energy loss of ˜280 eV, the titanium-L3,2 peak at an energy loss of ˜450 eV, and the oxygen-K edge at an energy loss of ˜530 eV. All spectra are normalized to the Ti edge peak intensity and vertically separated for clarity. (FIG. 2D) XANES results for TiC-derived films combined with results for anatase, Ti ₃ AlC ₂ , TiC and TiCl ₃ . Both TiC samples were reacted in TMAH at 50° C. for 3 days. The inset shows the derivative of the X-ray absorption near-edge structure (XANES). Figures 3A-3D Morphology of titanium carbide (TCO) flakes. (FIG. 3A) Typical transmission electron microscopy (TEM) image of TCO flakes with lateral size >4 μm. The SAD in the area circled in red is shown in the upper right inset. The two arcs indicate the fiber structure along the [110] and [200] directions. The bottom inset is a high-magnification view of the upper left corner showing nanofilaments frayed in the direction along the arc. (FIG. 3B) Scanning transmission electron microscopy (STEM) showing individual filaments with a width of ≈10 Å. The bottom inset shows nanofilaments chemically “pulled out” from a large central Ti ₃ AlC ₂ particle. (FIG. 3C) Atomic force microscopy (AFM) of TiC-derived TCO self-assembled nanofilaments heated in TMAH at 80° C. for 3 days and washed with water. (Figure 3D) Same as (Figure 3C), but after diluting the colloidal suspension 500 times and drop-casting onto a glass slide. The inset shows the height profile corresponding to the blue line in (Fig. 3D); the height of the thinnest filament is ≈1.5 nm. Figures 4A-4D (Figure 4A) Tauc plots of films derived from various precursors. The dashed line models the baseline with Urbach tail absorption; the solid line fits the linear part. Charge-discharge curve (Fig. 4B) Voltage profile of _{Ti3AlC2 -} derived electrode material when tested in a lithium-ion battery (LIB) at 20 ^mAg . The inset shows the cyclic voltammogram at 0.1 mV s ⁻¹ . (FIG. 4C) Charge-discharge curves of a TCO cathode when tested at various current rates in a lithium-sulfur (Li-S) battery. (FIG. 4D) Survival rate of cancer cells (see text). Values represent mean±SD (n=3); *p<0.05. 5A-5F (FIG. 5A) Ti ₃ SiC ₂ , (FIG. 5B) Ti ₃ AlC ₂ , (FIG. 5C) Ti ₂ SbP, (FIG. 5D) TiN, (FIG. 5E) TiB ₂ , and (FIG. 5F) Ti ₅ SEM micrograph of a cross-section of a FF made starting from _Si3 and after ethanol and LiCl cleaning. The inset shows the corresponding colloidal suspension and FF. Figures 6A-6C FFs from parent TiC, Ti ₃ AlC ₂ , Ti ₃ SiC ₂ precursors (black lines) (Figure 6A), 2D TCO membranes derived from them after cleaning with ethanol and without sonication (respectively). X-ray diffractogram (red, blue, and green curves) (shifted vertically for clarity). (FIG. 6B) Films derived from TiC (red, bottom), Ti ₃ AlC ₂ (blue, middle), and Ti ₃ SiC ₂ (green, top) after washing with ethanol and then LiCl solution. (FIG. 6C) Films derived from TiB ₂ (red, bottom), TiN (blue, middle), and Ti ₅ Si ₃ (green, top) after washing with ethanol and then LiCl solution. Figures 7A-7B (Figure 7A) Setup used to obtain XRD patterns from vertical alignment films in transmission mode. Inset shows Kapton tape with drop-cast film taped to a vertical aluminum sample holder. (FIG. 7B) XRD pattern of vertically oriented ethanol-washed FFs (shifted vertically for clarity) from the indicated precursors. The Kapton tape pattern is also shown. Asterisks indicate peaks belonging to unreacted precursors. In all but one case, the precursors were heated in TMAH solution at 50 °C for 3 days as described in the Materials and Methods section. In one case, TiC powder was soaked in TMAH at 50 °C for 11 days (blue, top). For XRD characterization, 1-1.5 ml of colloidal suspension was drop-cast onto Kapton tape with a pipette and air-dried. The 5° black vertical line comes from Kapton tape. The blue line is the eye's guide to the anatase-based 2D structure. Figures 8A-8F (Figure 8A) and (Figure 8B) Typical TEM images of TiC-derived flakes (50°C, 3 days) (Figure 8C) Same as (Figure 8A), except that TiC was The fibrous nature of the TCO flakes is emphasized. (FIG. 8D) Nanofilaments crystallizing from an amorphous TCO background. The inset shows a high-resolution image of a crystalline nanofilament 2-3 nm wide and a few microns long. In the previous case, the reaction product was washed with water. (FIG. 8E) Ti ₃ SiC ₂ -derived flakes captured from crushed FF (washed with ethanol at 50° C. for 3 days). (FIG. 8F) Nanofilaments (dark particles in the center) that appear to be chemically “pulled” from the Ti ₃ AlC _two- phase (washed with ethanol and water for 3 days at 50° C.). The inset shows the SAD pattern in the area circled in red. The inset in f shows both the faint ring (due to TCO) and the MAX phase spot. FIGS. 9A-9B (FIG. 9A) TEM and (FIG. 9B) AFM micrographs of TiC-derived material heated at 80° C. for 5 days and washed with water. AFM samples were spin-coated onto glass slides from the initial suspension after dilution. Figures 10A-10B (Figure 10A) Six-layer anatase structure. Slab thickness is ≒8 Å. (FIG. 10B) Phonon state density of the four-layer structure shown in FIG. 1C. Figure 11 XPS spectra after LiCl cleaning of the Ti 2p region (first column), C 1s region (second column), O 1s region (third column) and Fermi edge (fourth column) are row, top), Ti ₃ AlC ₂ - (second row), Ti ₃ SiC ₂ - (third row), TiN- (fourth row), TiB ₂ - (fifth row), and TiO ₂ -based ( Line 6) Obtained from film. The peak fits and results are summarized in Tables 4 and 7. The vertical dashed line is a guide for the eye. 12A-12B Ti 2p region (first row), C 1s region (second row), O 1s region of (FIG. 12A) Ti ₃ AlC ₂ -based and (FIG. _12B ) Ti ₃ SiC 2 -based filter membranes (third column), and XPS spectra as a function of treatment at the Fermi edge (last column). The dashed vertical lines are a guide for the eye. In particular, the position of the Ti peak appears to be unaffected in the case _{of Ti3AlC2} by the solution used to clean the film or after heating to 800 °C in Ar (spectrum above blue and below it). Compare the spectra of a). 13A-13E TiC (black, bottom), Ti ₃ AlC ₂ (red, second from the bottom), Ti ₃ SiC ₂ (blue, third from the bottom), TiN (green, third from the top), TiB ₂ ( XPS spectra of (Fig. 13A) N 1s and (Fig. 13B) Cl 2p regions of TCO FF derived from TiO ₂ (purple, second from top) and TiO 2 (yellow, top) powder, (Fig. 13C) derived from Ti ₃ SiC ₂ Si 2p spectrum of FF, (FIG. 13D) Al 2p spectrum of Ti ₃ AlC ₂ derived FF, (FIG. 13E) B 1s spectrum of TiB ₂ derived FF. All samples were washed with ethanol and LiCl before filtration and vacuum dried before XPS analysis. 14A-14B (FIG. 14A) Thermogravimetric plots of all samples heated to 800°C in Ar at 10°C/min. Ethanol-labeled samples were washed with ethanol, and LiCl-labeled samples were washed first with ethanol and then with LiCl solution. (FIG. 14B) TiC-derived film heated to 800° C. in air. c) Mass spectrometry results of b. Up to ≒400°C, most of the gas released is water. When the temperature exceeds 400°C, _CO2 is released. The black dashed vertical line is a guide to the eye. FIG. 15 Rietveld analysis of the XRD diffractogram of a LiCl washed filtration membrane heated to 800° C. in Ar. The value of ^χ2 is shown in the figure. The results are summarized in Table 8. The purple line shows the difference between the red fit and the black experimental result. FIGS. 16A-16B (FIG. 16A) XRD diffraction patterns of TiO ₂ -derived materials heated in TMAH for the times and temperatures indicated. For 2D anatase, the (104) and (105) peaks are absent, and the 63° peak is shifted in the 60° direction. (FIG. 16B) TEM of 20 nm anatase nanoparticles. The inset shows the high magnification image and SAD pattern of the obtained _TiO2 nanoparticles. 17A-17D Electrochemical performance of Ti ₃ AlC ₂ based TCO as electrode material for lithium ion batteries. (FIG. 17A) Electrochemical impedance spectroscopy Nyquist plot at open circuit potential, (FIG. 17B) showing specific capacity versus cycle number and specific current. (FIG. 17C) Voltage profile at specific current of 100 mA g ⁻¹ . (FIG. 17D) Specific capacity and coulombic efficiency versus number of cycles for the cell shown in c. Figures 18A-18B Electrochemical properties of TiC-based FF electrodes in Li-S cells: (Figure 18A) CV curve, (Figure 18B) cycling stability at 0.2 °C. The S load is 0.8 mg. The capacity remained more or less constant at ≈1000 mAh/g for about 300 cycles before fading. FIG. 19 provides an image of an exemplary mesoscopic material according to the present disclosure. Table 1 provides sources of exemplary powders and reagents used in this study. Table 2 summarizes exemplary precursors, Ti:TMAH molar ratios, and synthesis conditions. Table 3 shows the interlayer spacing (d) values and corresponding diffraction angles (2θ) obtained from the XRD pattern shown in Figure 2a, and the values obtained from seven different SAD patterns obtained from five different samples. This is a summary of comparisons. All samples derived from parent TiC were heated to 50°C and then washed with ethanol and water. Table 4 is a fitting summary of the XPS results shown in FIG. Table 5 provides the chemical composition of five different flakes inferred from the EELS measurements shown in Figure 2c. The last row shows a chemical reaction in which a total of O, C, and N, X, may be present. The flakes were prepared by dry rubbing a filter film made by heating TiC powder in TMAH at 50° C. for 3 days and then washed with ethanol. Table 6 shows the chemical composition of flake numbers from different precursors, estimated from EDS measurements. The last row shows possible Ti:O ratios for these samples. SEM-EDS measurements were carried out from cross-sections of filter films made from precursor Ti ₃ AlC ₂ , Ti ₃ SiC ₂ , Ti ₃ GaC ₂ powders reacted with TMAH at 50 °C for 72 h and washed with ethanol and then with LiCl solution. Obtained. TEM-EDS measurements were performed on samples prepared by dry rubbing filter films derived from Ti ₃ SiC ₂ and TiB ₂ made by reacting the powder with TMAH for 72 h at 50 °C and washing with ethanol. It was done. Table 7 provides the Ti:O chemistry obtained from the Ti region below the ≈459 eV peak and the O region below the ≈530 eV peak shown in FIG. Table 8 is a summary of the Rietveld analysis of the filter films after heating to 800° C. in Ar. The corresponding XRD pattern is plotted in FIG. 15.

The present disclosure may be more readily understood by reference to the following detailed description of desired embodiments and the examples contained therein.

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. In case of conflict, the present specification, including definitions, will control. Preferred methods and materials are described below, although methods and materials similar or equivalent to those described herein can be used in the practice or testing. All publications, patent applications, patents, and other documents mentioned herein are incorporated by reference in their entirety. The materials, methods, and examples disclosed herein are illustrative only and not intended to be limiting.

The singular forms "a," "an," and "the" include plural references unless the context clearly dictates otherwise.

As used herein and in the claims, the term "comprising" can include "consisting of" and "consisting essentially of" embodiments. As used herein, the terms "comprise(s)", "include(s)", "having", "has", "can", " "contain(s)," and variations thereof, are open-ended transitional phrases, terms, or words that require the presence of a named ingredient/step and permit the presence of other ingredients/steps. It is intended that However, such statements should also be construed as describing the composition or process "consisting of" and "consisting essentially of" the listed ingredients/steps; It allows the components/steps identified, along with any impurities that may arise therefrom, and excludes other components/steps.

As used herein, the terms "about" and "at or about" mean that the quantity or value in question can be about or about the same value as another value. means. As used herein, unless otherwise indicated or inferred, it is generally understood that it is a nominal value given with a variation of ±10%. This terminology is intended to convey that similar values promote equivalent results or advantages as recited in the claims. That is, amounts, sizes, formulations, parameters, and other quantities and characteristics are not, and need not be, exact, but are subject to tolerances, conversion factors, rounding, measurement errors, etc., and other values known to those skilled in the art. It is understood that the approximations and/or can be made larger or smaller as desired to reflect factors. Generally, an amount, size, formulation, parameter, or other quantity or characteristic is "about" or "approximate" whether or not explicitly stated as such. When "about" is used before a quantitative value, it is understood that the parameter also includes the particular quantitative value itself, unless specifically stated otherwise.

Unless indicated to the contrary, numerical values represent numerical values that are the same when reduced to the same significant figures, and are less than the experimental error of conventional measurement techniques of the type described herein for determining the numerical values. It should be understood that it includes numerical values different from values.

All ranges disclosed herein are inclusive of and independent of the stated endpoints (e.g., "between 2 grams and 10 grams, and all intermediate values are inclusive of 2 grams, 10 grams, gram, and all intermediate values). The endpoints of ranges and any values disclosed herein are not limited to exact ranges or values, but are sufficiently imprecise to include values approximating those ranges and/or values. All ranges are combinable.

As used herein, approximate expression can be applied to modify any quantitative expression that can be changed without resulting in a change in the fundamental functionality with which it is associated. Thus, values modified by terms such as "about" and "substantially" may, in some cases, not be limited to the exact values specified. At least in some cases, the approximate representation may correspond to the precision of the instrument measuring the value. Also, the modifier "about" should be considered to disclose a range defined by the absolute values of the two endpoints. For example, the phrase "from about 2 to about 4" also discloses the range "from 2 to 4." The term "about" can refer to plus or minus 10% of the stated value. For example, "about 10%" can refer to a range of 9% to 11%, and "about 1" can mean 0.9 to 1.1. Other meanings of "about" are clear from the context, such as rounding, so for example "about 1" can also mean 0.5 to 1.4. Furthermore, 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 containing components A and B may be a composition containing A, B and other components, or may be a composition consisting only of A and B. All documents cited herein are incorporated by reference in their entirety for all purposes.

2D flakes were obtained in all cases except when TiO ₂ was used as the precursor. A typical cross-sectional scanning electron microscopy (SEM) image of a TiC-derived film (Fig. 1b) clearly shows the two-dimensional nature of the FF. This photomicrograph is particularly clear in that it shows both undigested TiC particles (bottom right) and flakes. A colloidal suspension with a concentration of 10 g/L is shown in the inset of Figure 1b. SEM images of other films are shown in FIG. The color of FF varied from light gray to dark gray. The fact that these flakes can be synthesized from non-layered precursors, yielding structurally and chemically similar FFs, is strong evidence for a bottom-up approach. Our interpretation is that TMAH is a nearly universal solvent that dissolves the precursor and releases Ti atoms that spontaneously react with C and O in TMAH/water to form 2D flakes consisting of self-assembled nanofilaments. (see below). Thus, the role of TMAH is twofold: solvent and template forming agent.

The X-ray diffraction (XRD) pattern of the _{Ti3AlC2 -} derived film after ethanol washing (inset of Fig. 2a) is typical of a 2D material. [7,9] XRD patterns of dried FF obtained from other precursors are shown in FIG. It is noteworthy that in most cases there are no peaks related to precursors. To know the basic structure, an XRD pattern (Fig. 2a) of the vertically aligned FF was obtained. [14] (see Figure 7a). This was obtained after heating Ti ₃ AlC ₂ at 50° C. for 3 days, followed by washing with ethanol and water. The red vertical line was obtained as follows: first, the c lattice constant LP was calculated from the horizontally oriented film (inset of Fig. 2a). The positions of all peaks were then calculated using the structure shown in Figure 1c. All surfaces with non-zero l index were erased, leaving a red line. The good agreement between the density functional theory (DFT) generated LP and the experimental LP (inset of Fig. 1d) confirms that we are dealing with a 4 Ti-layer anatase-based 2D material. (described later). Other vertically oriented film patterns obtained from other precursors are shown in Figure 7b. In all cases, peaks with the same angle were obtained. This is extremely important and cannot be overemphasized as it indicates that the precursor chemistry does not change the formed structure containing the LP.

Transmission electron microscopy (TEM) images of TiC, TiSiC ₂ and Ti ₃ AlC ₂ derived flakes revealed the presence of 2D flakes with lateral size >1 μm (Fig. 3a, Fig. 8). Selected area diffraction (SAD) of the latter in some areas resulted in three major rings (see insets in Fig. 8b and c). Converting the d-spacing of the rings to 2θ values (blue squares in Figure 2a) showed good agreement with the XRD peaks, confirming that the SAD pattern is representative (see Table 3 for more detailed results). ). More interestingly, in other regions two sets of circular arcs (Fig. 3a and inset of Fig. 8a) were observed. One of the circular arcs indicates that the long axis of the nanofilament is in the [110] direction, and the other indicates that it is in the [200] direction. The angle between these is shown in both the inset and the main micrograph. These are in the same direction as the frayed fibers seen at the edge of the top left sheet. The locations where arcs have been observed are limited. The region where three rings were observed was more ubiquitous, suggesting the presence of small nfs pointing in all directions. Similarly, at this stage, we cannot deny the existence of truly amorphous regions.

The scanning transmission electron microscopy (STEM) micrograph (Fig. 3b) clearly shows the fibrous nature of the sample. The width of individual nanofilaments is estimated to be ≈1 nm. Its thickness is ≈5.9 Å, so we are dealing with nanofilaments with a cross-section of ^{approximately} 6 x 10 Å and a length of micrometers (see inset of Fig. 3b and Fig. 8c). Other TEM micrographs are shown in FIG. It is noted that the theoretical surface area of these nanofilaments is ≈1500 m ² /g.

Figures 3c and 9 are TEM and atomic force microscopy (AFM) maps of TiC-derived samples spin-coated on glass (washed with water at 80°C for 5 days). The fibrous nature and self-alignment tendency of the product is evident. When the same suspension was diluted 500 times and drop cast, individual nanofilaments were separated (Fig. 3d). The AFM trace along the blue line in Figure 3d shows that the minimum ribbon thickness or height is ≈1.5 nm (inset in Figure 3d).

To determine the number of Ti layers per filament, first-principles calculations were used to predict the LP. To this end, the lowest energy anatase (101) surface [16] serves as the upper and lower boundary from the 2- (not shown), 4- (Fig. 1c), and 6-Ti layers (Fig. 10a). We performed relaxation calculations for three supercell structures. (Note that our coordinate system is different from that of anatase; here the c-axis is the stacking direction; see the Crystallography section of SM). Then, two O atoms were replaced by one C atom at the slab center to obtain the overall chemical composition of TiO _2-2x C _x (x is 0.25 or Ti ₄ O ₆ C). . This is to take structural C into consideration and to dynamically stabilize the structure (FIG. 10b). All other configurations resulted in dynamic instability. As shown in the inset of Fig. 1d, the b-axis LP of the three structures is in good agreement with the experimental values, especially considering that the DFT calculations were performed at 0 K. However, when the number of Ti layers increases to 4 or 6, a large increase in a-LP is observed, approaching the experimental value (blue curve in the inset of Fig. 1d). The thicknesses of the 4-layer and 6-layer anatase are ≈5.9 Å and ≈8 Å, respectively. The diameter of TMA cations ranges from 4.5 to 6 Å [17,18]. Using the lower limit, the d-spacing between filaments in the 4-layer and 6-layer structures is 10.4 Å and 12.5 Å, respectively. Using the upper limit, we obtain a d-spacing of the four-layer structure (11.9 Å), which is in good agreement with the d-spacing of 11.5 obtained from XRD (Fig. 2a and inset of Fig. 6a). That is, the experimental values are consistent with a 4-layer structure, and a 6-layer structure is too thick.

Raman spectroscopy of many FFs (Fig. 2b) shows that all peaks belong to anatase, regardless of the precursor chemistry. [15,19]

A comprehensive study by X-ray photoelectron spectroscopy (XPS) was performed to elucidate the chemical properties of the flakes (Figures 11-13 and Table 4). The binding energy of Ti and O was found to be a weak function of precursor chemistry (Fig. 11), cleaning protocol, or heating to 800 °C in Ar (Fig. 12a). This again confirms the chemical similarity of all films. Further evidence of the bottom-up approach is that except for the _{Ti3SiC2 -} derived film, which shows a small Si peak, all other XPS spectra are composed of only three elements, Ti, C, and O, regardless of the starting precursor. (Figure 13).

As discussed, it was not possible to quantify the C content in the thin sections. EELS of several TiC-based flakes showed that the atomic ratio of Ti:C:O was ≈1:1:1 (Fig. 2c and Table 5). These flakes contained small amounts of nitrogen, which will be ignored here for simplicity. It is important to note that both SEM and TEM EDS confirmed that the Ti:O ratio was ≈1.0 (Table 6). Based on this ratio, if C is not present in the structure, the oxidation state of Ti must be ≈+2, which is similar to the X-ray absorption near-edge structure (XANES) at the Ti K edge of TiC-derived films. ) measurements (Fig. 2d) show that the average oxidation state (AOS) is between +3 and +4. In all cases, the O:Ti ratio in XPS was closer to 3 than 1 (Table 7).

Thermogravimetric analysis (TGA) in Ar up to 800 °C was performed on selected films to better understand the chemistry and flake morphology. The results are shown in Figure 14a. With the notable exception of the TiO ₂ derived films, in all other cases two major weight loss phenomena were observed upon heating the LiCl cleaned films. One is before ≒200°C, and the other is at a temperature of ≒300°C or higher. The latter is very steep for TiB ₂ , TiC and Ti ₃ SiC ₂ derived films. In most cases, the weight loss at ≈300°C was approximately 4%. The weight loss above 300° C. for Ti ₃ AlC ₂ and TiN derived films was more diffuse, but still totaled ≈4%. The sharpness of the weight loss at 300°C is best seen in Figure 14b for the TiC film heated to 800°C in air. In this experiment, the TGA was equipped with a mass spectrometer and the results are shown in Figure 14c. The only gas released up to 400°C was water. The first is probably weakly bound interlayer water, and the second is likely hydration water bound with Li ions. The absence of high atomic number species indirectly proves that the LiCl cleaning step removed the interlayer spaces of TMA cations and other reaction products. Not surprisingly, the weight loss of the film washed with ethanol only was greater (red curve in Figure 14a).

After performing TGA, an XRD pattern of the resulting powder was obtained (Figure 15). As a result of Rietveld analysis of the XRD pattern, the values shown in Table 8 were obtained. In all cases, two main phases were identified: lithium titanate, LT, phase - Li _1.33 Ti _1.67 O ₄ and rutile or anatase. For Ti ₃ AlC ₂ , Ti ₃ SiC ₂ , TiC, the molar ratio of TiO ₂ /LTA is ≈7:3; for TiB ₂ , the ratio is close to 1:1; for TiO ₂ , there is almost no LT . Note that the higher the Li content, the higher the proportion of Ti ³⁺ in the film. Therefore, our approach can be used to tune the Ti ³⁺ /Ti ⁴⁺ ratio considered in many applications.

Even after washing with ethanol only and heating the film to 800° C. in Ar, no Li-containing phase was obtained. Therefore, the presence of the LT phase suggests that interlayer cations (TMA ⁺ and/or protons) were exchanged with Li during the LiCl cleaning step in a manner very reminiscent of the MXene studies. . [20,21] _TiO2 -derived samples were only slightly lithiated even after cleaning with LiCl (Table 8). The TGA of this sample (black curve in Figure 14a) is also an outlier for the same reason. Cation exchange eliminates the possibility that we are dealing with layered double hydroxides. The absence of Cl signal in XPS (see Figure 13b) also supports this conclusion.

Based on the EELS, XANES, DFT and TGA results, the chemical properties of the flakes are given by Z _δ (Ti ⁴⁺ ) _1−δ (Ti ³⁺ ) _δ O _2−2x C _x , where x<1.0 It is reasonable to assume that. Z is a cation explaining that the oxidation state of Ti is <4+. Otherwise, the reduction in oxidation state must be balanced by cations. Note that this conclusion assumes that the nanofilaments are defect-free, a highly unlikely scenario. The fact that many films are dark gray to black strongly suggests the presence of defect states in the bandgap.

The overall situation is even more complex. For example, in some regions the Ti:X ratio (X=O+C+N) approaches 1 (see spots 1 and 5 in Table 5). We acknowledge that we are dealing with a very complex system that is not necessarily homogeneous and requires a lot of work to decipher. Despite these comments, our conclusions regarding the structure of the flakes and the presence of C in the structure remain valid.

Before discussing the properties, it is useful to discuss the mechanisms involved in the formation of nanofilaments and 2D layers. Starting from tetra-n-butyl titanate and TMAH, Chen et al. observed that the presence of TMAH provides organic cations to assist and direct the Ti-octahedra polycondensation process, resulting in the observed rectangular nanocrystalline anatase. It was concluded that a regular arrangement of particles was obtained. [15] Tan et al. hydrothermally treated _TiCl4 at 125 °C. [19] When the reaction time was 1 h and 4 h, their XRD patterns were the same as in Figure 2a except for the (240) position around 60°2θ. Increasing the reaction time to 12 and 24 hours converted the 2D material to bulk anatase. They proposed a model in which TMAH helps assemble Ti octahedra into 2D layers while simultaneously inserting the resulting sheets. There is no reason to think that this mechanism does not apply here as well, except that our material does not convert to bulk anatase because we are working at temperatures low enough for TMA molecules to be more stable [22]. Finally, unlike all previous studies, TMAH not only caps the low energy (00l) plane [19] but also has to cap the second plane perpendicular to the growth direction. This creates a situation where growth is limited to one dimension. The insets of Fig. 3b and Fig. 8f suggest that the filament is chemically “pulled” from the precursor and the polycondensation process occurs at the interface (without being bound to a particular theory). Once the nanofilaments are formed, they need to self-assemble into 2D flakes. Figure 8d is a snapshot showing how nanofilaments self-align to form "crystalline" regions in certain regions.

Films obtained from TiC and MAX phases were electrically conductive, with conductivities ranging from 0.01 to 0.05 S/cm, whereas those obtained from TiO ₂ , TiB ₂ were not. Their conductivity is approximately 5-6 orders of magnitude lower than that of MXene, which is in the range of 2,000-25,000 S/cm, but that of typical oxides, especially the common version of layered titanates, i.e. lepidochrome. This is clearly an order of magnitude higher than that of the site [23-25]. Conductivity is not always present, suggesting that unknown variables currently under investigation are at play.

In order to clarify the electronic structure, ultraviolet-visible light absorption spectra from 200 nm to 800 nm were measured. The Tauc plots (Fig. 4a) of all films showed clear signatures of indirect bandgap _E , as well as a pronounced Urbach tail due to transitions between subgap states. When using a modified Tauc method to deconvolute the interband transitions from the contribution of disorder-related Urbach tail states [26], it was concluded that the indirect band gap is in the range of 4 eV. This value is the highest reported for anatase, but is consistent with an increase in E _g with decreasing size. [27] Liao et al. [28] predicted and confirmed E _g ≈3.6 eV for 2-Ti layered 2D anatase flakes. Our flakes are composed of ≈6 x 10 Å ² nanofilaments, so the E _g is even higher. This record TiO ₂ E _g value cannot be overstated as it indirectly confirms the extreme dimensions of our nanofilaments. Note that at 3.3 _eV , the E _g of our TiO2 _- based nanoparticles is close to that of bulk anatase, as expected (Fig. 4a).

Interestingly (and without being bound by any particular theory or embodiment), here we note that the relationship between the Ti ³⁺ content inferred from the Li concentration and the Urbach tail is similar to that suggested by some. There is no such correlation [29]. Therefore, we tentatively concluded that this tail and conductivity are caused by point defects. In some of the EELS measurements, the Ti fraction approaches 0.5 (Table 5), suggesting the formation of O/C vacancies. Regardless of this comment, further research is needed to understand why some of these films may exhibit electrical conductivity.

To explore potential applications, we explored the performance of our 2D flakes in lithium-ion batteries (LIBs) and lithium-sulfur batteries (Li-S). The results are shown in Figures 4b and c, respectively, and promising results were obtained in both cases. A detailed discussion can be found in the SM (see Figures 17 and 18). In the case of LIB, the absence of lithiation and delithiation peaks at 1.64 V and 2.1 V (inset of Fig. 4b) confirms that this electrode is neither _TiO2 nor layered titanate [ 30, 31]. Furthermore, the Coulombic efficiency of this electrode was ≈99.3% after 200 cycles (Fig. 17d), reflecting a highly efficient electrochemical cycle.

A lithium-sulfur (Li-S) coin cell with a Li anode and a TiC-derived TCO cathode was assembled and cycled. The results are shown in Figure 4c and detailed in SM.

These results are included to confirm the 2D nature of the obtained materials and their potential. However, these results can be greatly improved with a better understanding of what is being obtained. Regardless of these comments, we acknowledge that more research is clearly needed beyond the scope of this paper to understand its mechanisms and involvement. However, it goes without saying that these materials show great potential, especially as Li-S cathodes. For example, as shown in Figure 18b, the capacity remained constant for approximately 300 cycles at ≈1000 mAh/g before fading.

Finally, to further demonstrate the versatility of TCO, we explored its potential biomedical applications and found that it can indeed be used in cancer treatment (Fig. 4d). Here, mouse 4T1 breast cancer cells and B16-F10 melanoma cells were treated with different concentrations of TiC-derived TCO for 24 hours, and then the survival rate was measured using an MTT assay. At a concentration of 200 μg/ml, TCO particles were able to induce cancer cell death and were more effective in 4T1 breast cancer cells than in B16-F10 melanoma cells. Accordingly, a composition according to the present disclosure can be administered to a cancer-containing sample, and this administration can induce death of cancer cells.

conclusion

We have discovered a simple, inexpensive, relatively high-yield, near-room temperature, fully scalable, one-pot, bottom-up approach to fabricate 2D titanium carboxide films composed of nanofilaments. By heating 11 different layered and non-layered titanium-based precursor powders in TMAH at different temperatures (25 °C to 85 °C) for various times, 10 of them were converted into anatase-based 2D flakes; It was constructed into ≈6×10 Å ² nanofilaments with substantial C content. Some of the films were dark in color and conductive, with conductivities ranging from 0.01 to 0.05 S/cm. However, since there was no correlation between the Urbach tail and the proportion of Ti ³⁺ inferred from the total Li content, the conductivity was probably caused by point defects rather than the reduced oxidation state. I concluded that there is. TCO showed good performance as an electrode for LIB and Li-S batteries. It is also expected to have biomedical applications.

Materials and methods

Film processing

This synthesis process involves soaking the precursor powder in 25 wt% TMAH in a polyethylene jar heated on a hot plate for a period of 24 hours to 1 week at temperatures ranging from room temperature (RT) to 85 °C. . After reaction with TMAH, a dark black precipitate (except for _Ti2SbP , _TiB2 and _TiO2 ) was obtained, which was collected and washed with ethanol, then shaken and incubated until a clear supernatant was obtained. Centrifugation was performed at 3500 rpm for multiple cycles. Once the supernatant was clear, 30 mL of deionized water was added to the washed product and shaken for 5 minutes. A stable colloidal suspension was obtained after centrifugation at 3500 rpm for 0.5 h without sonication. Unreacted powder precipitated. This colloid was then vacuum filtered to produce FF, a portion of which was characterized.

In some cases, an additional step of washing with LiCl solution was performed and the resulting flakes were characterized. A 5M LiCl solution was added to the black colloidal suspension obtained above. As a result, disaggregation occurred. The precipitate was shaken, centrifuged at 5000 rpm for three cycles, and washed with deionized water. The LiCl/deionized water wash was repeated until pH≈7. Next, the washed precipitate was sonicated in a cold bath for 1 hour while flowing Ar, shaken for 5 minutes, and then centrifuged at 3500 rpm for 10 minutes. The colloidal suspension was filtered to obtain FF. Next, the FF was dried in a vacuum chamber overnight and then further characterized.

In a few cases, the black slurry produced from the reaction of TMAH and TiC was directly centrifuged (5000 rpm, 5 min) without the addition of solvent, the supernatant was decanted, and the precipitate was suspended in 20 mL of deionized water. After shaking for 5 minutes, centrifugation was performed at 3500 rpm for 30 minutes. The resulting black colloidal suspension was used for XRD (not shown) and TEM examination.

The yield was calculated as the ratio of moles of Ti in the anatase-like structure produced (using the molar mass of TiO ₂ for simplicity) to the moles supplied from the precursor. For example, the yields of TiC and Ti ₃ AlC ₂ are 19% and 28%, respectively. Generally, yields are on the order of ≈20% depending on the starting precursor. The solids loading of the colloidal suspension is of the order of 10 g/L.

X-ray diffraction, XRD

XRD patterns of air-dried samples were obtained using a powder diffractometer (Rigaku SmartLab) using Cu Kα radiation in the 2-65° 2θ range, with a step size of 0.02° and a dwell time of 1 s/step. Obtained with Bragg-Brentano geometry. An XRD pattern of the vertically oriented film was also obtained in transmission mode.

Raman spectroscopy, RS

Raman scattering spectra were collected at 300 K in air from a number of precursor FFs (Fig. 2b). The sample was irradiated with a power of 3.75 mW and probed with a 532-nm laser focused to a spot diameter of ~0.5 μm. Scattered light was collected with geometric backscatter, dispersed and detected using a single-axis monochromator equipped with a charge-coupled detector array (Horiba XploRA, Edison NJ).

X-ray photoelectron spectroscopy, XPS

XPS was performed using a spectrometer (VersaProbe 5000, Physical Electronics, Chanassen, Minn.). Monochromatic Al-Kα X-rays with a spot size of 200 μm were used. High-resolution spectra were collected with a pass energy of 23.5 eV, an energy step of 0.05 eV, and a step time of 0.5 seconds. The number of repetitions of one scan was 10 times. The XPS spectrum was calibrated with the main CC peak set at 285.0 eV. The peaks were fitted using an asymmetric Gaussian/Lorentzian line shape. Background was determined using the Shirley algorithm. All samples were mounted on the XPS stage with carbon tape.

scanning electron microscope, SEM

Micrographs and elemental compositions were obtained using a SEM (Zeiss Supra 50 VP, Carl Zeiss SMT AG, Oberkochen, Germany) equipped with an energy dispersive X-ray spectrometer (EDS, Oxford EDS, Oxfordshire, UK). Reported EDS values are the average of at least two low magnification measurements of randomly selected areas with an accelerating voltage of 15 kV and a dwell time of 60 seconds.

Atomic force microscope, AFM

Filament and flake thicknesses were measured using AFM (Multimode 8 AFM by Bruker Nano Surfaces). Peak force tapping AFM imaging mode was applied to obtain the surface morphology and height profile. Scanning was performed using a ScanAsyst-Air silicon nitride probe at a scan rate of 0.6 Hz. Topography images were recorded with a resolution of 256*256 pixels and analyzed with Nano Scope Analysis software.

Transmission electron microscope, TEM

TEM imaging and electron diffraction patterns were collected using a JEOL JEM2100F field emission TEM. The TEM was operated at 200 keV and the image resolution was 0.2 nm. Images and diffraction patterns were collected with a Gatan USC1000 CCD camera. Scanning transmission electron microscopy (STEM) was performed on a monochromatic and dual Cs-corrected FEI Titan3 60-300 operating at 300 kV.

electron energy loss spectroscopy, EELS

STEM-EELS spectra were acquired by averaging 100 spectra acquired for 1 second each using a Gatan GIF Quantum ERS post-column imaging filter with a 0.25 eV/channel energy dispersion and a collection half-angle of 55 mrad. Elemental quantification of existing edges was performed using the built-in function of Digital Micrograph.

X-ray absorption edge structure, XANES

Ti K-edge isotropic XANES spectra were recorded at a position of 54° from the film normal using circularly polarized X-rays provided by the first harmonic of a HELIOS-II type helical undulator (HU-52). Ta. The X-ray beam was monochromated using a fixed exit double crystal monochromator equipped with a pair of Si(111) crystals. The total fluorescence yield signal was collected by a Si photodiode mounted in a backscatter geometry. The spectra were corrected for the effects of self-absorption. The samples were compressed powder pellets with a thickness of ≈1 mm. Isotropic XANES spectra were normalized to have a single edge jump far above the absorption edge. The photon energy scale was calibrated using the pre-peak maximum in the absorption spectrum of the Ti film, which was set at 4965.6 eV. The spot size was ^0.4x0.3mm2 . The experiments were conducted at the European Synchrotron Radiation Facility (ESRF) ID12 beamline in Grenoble.

electrical resistivity

Electrical resistivity measurements were performed at room temperature using a four-point probe device (Loresta-AX MCP-T370, Nitto Seiko, Japan) and converted into electrical conductivity values.

Thermogravimetric analysis, TGA

A thermobalance (TA Instruments Q50, New Castle, Del.) was used for TGA analysis. A small piece of FF (≈20 mg) was placed in a sapphire crucible and heated to 800 °C at 10 °C/min while purging with Ar at 10 mL/min. One experiment used a thermobalance attached to a mass spectrometer. These measurements used a thermal analyzer (TA instruments, SDT 650, Discovery Series) combined with a mass spectrometer (TA instruments Discovery Series) operating at an ionization potential of 40V. The samples were kept at room temperature for 0.5 h and then heated to 800° C. at a rate of 10° C./min under a flow of dry compressed air of 50 mL/min. Carrier gas and evolved gas from the sample were scanned and measured in the range of 1 to 100 atomic mass units. The ion current for each m/z (mass/charge ratio) was normalized to the initial sample weight.

UV-vis.

UV-VIS spectra were recorded using a spectrophotometer (Evolution 300 UV-Visible, Thermo Scientific). Measurements were performed in transmission mode on 1-10 μm thick films coated on quartz slides.

DFT calculation

First-principles calculations were performed using the Vienna ab initio simulation package (VASP). [32] Projector-enhanced wave method (PAW) was used with a plane wave basis extended to a kinetic energy cutoff of 600 eV. The exchange-correlation effect was described by a generalized gradient approximation using the Perdew, Burke, and Ernzerhof (PBE) function [33]. Brillouin zone integration was performed using the Gaussian smear method with a smear width of 0.05 eV. The electronic configurations of the pseudopotentials used are C:[He]2S ² 2P ² , O: [He]2s ² 2p ⁴ , Ti_sv: [Ne]3s ² 3p ⁶ 3d ² 4s ² . The computational supercell was constructed using a slab model, consisting of various anatase (101) atomic layers, with periodicity along the a- and b-axes of the supercell. The supercell geometry and atomic positions were relaxed until the force on each atom was <5 meV/Å. A vacuum region of 15 Å was added along the c-axis (new coordinate system) of the supercell to eliminate interactions between periodic images perpendicular to the slab. For structure optimization, the first Brillouin zone had 16x6x1 k-point sampling, and for phonon calculations, 8x3x1 supercell and 2x2x1 k-point sampling were used.

electrochemical measurement

Lithium ion battery, LIB

To evaluate the electrochemical performance of TCO as an electrode material as a LIB material, TCO was tested in a half-cell configuration on Li metal. The TCA working electrode was prepared by drop-casting a slurry of active material containing a binder and carbon additive onto a carbon-coated copper foil. The slurry contained 40.0 mg active material, 5.0 mg poly(vinylidene fluoride) (PVDF, Sigma Aldrich, USA), binder N-methyl-2-pyrrolidinone (NMP, 99.5%, Acros Organics, Extra Dry). over Molecular Sieve, Germany) solvent, and 5.0 mg of carbon black. The prepared electrodes were dried at 60°C overnight. The mass loading of the electrode was ~1.2-1.5 mg/ ^cm2 . A two-electrode CR2032 type coin cell was assembled in an Ar-filled glovebox with O ₂ and H ₂ O <0.1 ppm. Li metal foil was used for the counter electrode. 1M LiPF ₆ with ethylene carbonate (EC)/ethyl methyl carbonate (EMC) 3:7 (weight ratio) and glass fiber were used as the electrolyte and separator, respectively. CV and galvanostatic charge-discharge tests were performed using an electrochemical workstation (BioLogic VMP3) and a cycler (Landt CT2001A,) with a cut-off electrochemical voltage window of 0.001 to 3.0 V for Li/Li ⁺ . Ta. Electrochemical impedance spectrometry was performed at a frequency of 100 kHz to 10 mHz using an electrochemical workstation (BioLogic VMP3).

sulfur lithium battery

In order to evaluate the performance of TCO as a sulfur host in a Li-S battery, a TCO/S positive electrode was fabricated by a method using a slurry. Briefly, 35 wt% vacuum-dried TCO, 35 wt% S, S, 20 wt% conductive carbon (Alfa Aesar, Super P), and 10 wt% battery grade PVDF binder (MTI Corp.) were mixed. A slurry was prepared. The material was manually ground in a mortar and pestle until the mixture was homogeneous. Then, N-methyl-2-pyrrolidone (TCI, USA) was slowly added until the required visible viscosity and homogeneity of the slurry was achieved (~25 minutes). The slurry was then cast onto aluminum foil at a thickness of 20 μm using a doctor blade (MTI Corp., USA). After casting, the slurry was kept in a closed fume hood for 2 hours, then transferred to a vacuum oven and dried at 50°C for 12 hours.

The dried TCO/S cathode was cut into a disk shape using a hole punch (diameter 11 mm). The electrodes were then weighed and transferred to an Ar-filled glove box (MBraun Lab star, O ₂ <1 ppm, and H ₂ O <1 ppm). CR 2 using TCO / S cathode, 15.6 mm in diameter, 450 μm thick Li disk node (Xiamen TMAX Battery Equipment), 3 -layered separator (Celgard 2325), stainless steel spring, two spaces, and electrolytes. 032 (MTI Corporation and Xiamen TMAX Battery Equipment) coin-shaped Li-S cells were assembled. An electrolyte solution containing 1M LiTFSi and 1 wt% LiNO ₃ mixed with 1,2-dimethoxyethane and 1,3-dioxolane at a volume ratio of 1:1 was purchased (TMAX Battery Equipment, China), and according to the manufacturer, it contained a trace amount of oxygen. and water (H ₂ O < 6 ppm and O ₂ < 1 ppm). Before performing electrochemical experiments, the assembled coin cells were rested at open circuit potential for 10 hours. Cyclic voltammetry was performed using a potentiostat (Biologic VMP3) at a voltage of 0.1 mV between 1.8 and 2.6 V with respect to Li/Li ⁺ . It was run at a scan rate of s ⁻¹ . Long-term cycling stability tests were performed using a battery cycler (Neware BTS 4000) at various C rates (where 1C=1675mAh.g ⁻¹ ) between voltages 1.8 and 2.6V. Li-S cells were conditioned for 2 minutes. After cycles at 0.1C and 0.2C, a long cycle was carried out at 0.5C.

biological test

One day before treatment, 4T1 and B16-F10 cells were added to 96-well plates at a density of 10,000 cells/well. The cells were cultured for 24 hours at 37° C./5% CO ₂ in RPMI-1640 medium supplemented with 10% fetal bovine serum and 100 IU/mL penicillin/streptomycin. Thereafter, it was treated with TiC-based TCO at concentrations of 10 μg/mL, 50 μg/mL, and 200 μg/mL. After 24 hours of treatment, thiazolyl blue tetrazolium bromide (MTT) assay was performed according to the manufacturer's protocol. Absorbance was measured at 570 nm and 630 nm. Relative cell viability was determined by comparison with the absorbance of untreated cells. All measurements were performed in triplicate. Data were analyzed using two-way ANOVA and Tukey's post hoc test.

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Supplemental disclosure

Reason for LiCl cleaning

Based on previous studies on ion exchange and colloidal stability of 2D materials [1-9], a LiCl cleaning step was performed for the following reasons.

To remove TMA cations from the interlayers. This was useful because in some cases non-conductive films were formed by TMA cations.

To prove the existence of exchangeable cations between the layers. If there were no exchangeable cations, Li ⁺ ions would not be intercalated between the layers.

After heating the filtered film FF to 800 °C in Ar, knowing the proportion of the crystalline phase obtained allowed the content of Ti ³⁺ to be estimated.

X-ray diffraction

Not surprisingly, X-ray diffraction, or XRD, of the horizontally oriented film failed to reveal its underlying structure. Instead, a similar setup to Ghidiu et al. [10] was used to obtain a pattern of vertically oriented films. To obtain films, 1-3 ml of the colloidal suspension was drop-cast using a pipette onto Kapton tape attached to a glass slide (inset of Figure 7a). Three layers of colloidal suspension were drop cast and allowed to dry between applications. Drying was performed in a Petri dish at room temperature, RT using a fan. The drop-cast samples were fixed in a vertical sample holder using double-sided tape (Fig. 7a). The sample holder was then aligned to maximize the signal through the sample.

crystallography

Note that the coordinate system used here is not that of bulk anatase, but the coordinate system shown at the bottom left of Figure 1c. Following our recipe, the grown NFS-based 2D flakes are preferentially oriented along (110), which is the lowest energy plane of bulk anatase (i.e., anatase coordinate system). To be consistent with the 2D literature, in our system the stacking direction of the flakes is along the c-axis. That is, in our coordinate system, this is the (00l) plane.

Transmission electron microscope, TEM

The TEM image shows that the aligned area is only a small part of the whole. In a significant proportion, the nanofilaments are not aligned but randomly oriented within the plane of the flake. This was also confirmed by selected area diffraction patterns (SAD), where diffraction rings were visible in most of the flakes.

electron energy loss spectroscopy, EELS

EELS spectra of five types of particles were measured for TiC-based flakes that had been heated in TMAOH at 50° C. for 3 days and then washed with ethanol. Figure 2c includes a carbon-K edge at an energy loss of ˜280 eV, a titanium-L3,2 peak at an energy loss of ˜450 eV, and an oxygen-K edge at an energy loss of ˜530 eV. All spectra are normalized to the titanium edge peak intensity. Thick particles exhibit a steep background, which is more easily seen at lower energies of the spectrum. The top and bottom spectra are clearly lower in intensity than the middle three particles. Among the five particles, the upper and lower spectra contain almost the same amount of C, but the chemical composition of the middle three (2, 3, and 4) is Ti:C:O atomic ratio ≒ 1:1:1. Consistent. All spectra also show a small amount of NK (not shown) with an energy loss of ~400 eV. In this paper, we ignore this small amount of N. The results of these spectra are summarized in Table 5. Since the intensity of the C-loss peak did not change with time under electron beam irradiation, it is presumed that C is in the backbone of the structure.

Importantly, both particles contained significantly higher proportions of Ti. In one case, the atomic fraction of Ti is close to 0.5. This suggests that Ti atoms are chemically reduced to an average oxidation state of +2 during the process.

It should be noted here that the intensity of the various peaks did not change even with long-term illumination under the beam, so it is assumed that C originates from within the structure. It may originate from an otherwise contaminated sample. Even when heated to 500° C. in a TEM chamber, the Ti/C ratio did not change.

X-ray absorption edge structure, XANES,

XANES experiments were performed on the Ti K edge of Ti-derived films at ESRF beamline ID12. XANES spectra at the K-edge of transition metals are dominated by dipole transitions to unoccupied 4p states, usually accompanied by structured pre-edge peaks associated with transitions to 4p-3d hybrid states. [11] The energy position of the absorption edge, especially the pre-edge peak, is generally related to the oxidation state and coordination of the absorbing atom. Comparing the XANES spectrum of our TCO film (Fig. 2d) with _the spectra of reference compounds of Ti4 ⁺ (anatase), TiC, _Ti3AlC2 and Ti3 ⁺ ( _TiCl3 ), the average Ti oxidation state of the TCO film It can be seen that is between 3+ and 4+. These results clearly indicate that our material is not pure anatase, i.e., C-free anatase.

Both covalent bonds and 3d counts can lead to energy shifts in the K-edge XANES spectra of Ti. The former mechanism mainly appears at the main edge. However, the energy position of the weak features below the main edge (resulting from the quadrupole transition 1s->3d) is dominated by the effects of 3d occupancy. Comparing the first derivative of the XANES spectra in the energy range from 4964 eV to 4968 eV (inset of Fig. 2d), it is clear that the oxidation state of Ti in TiC is close to 3+, similar to the reference compound _TiCl3 . On the contrary, TiCO contains both Ti ³⁺ and Ti ⁴⁺ states, and its differential spectrum has two peaks, and the energy positions of these peaks are similar to that of the TiCl ₃ peak and the TiO ₂ first peak. is consistent with

X-ray photoelectron spectroscopy, XPS

Typical XPS spectra of all films are compared in FIG. The peaks were fitted and the results are summarized in Table 4. The Ti:O ratio of the films is summarized in Table 7. The latter was determined from the area of the Ti peak at ≈459 eV peak and the O peak at ≈530 eV peak. This ratio is approximately 1:3.

The C 1s spectrum (second column of Fig. 11) has three peaks, the largest peak centered at binding energy (BE) ≈285 eV, and two smaller peaks centered at ≈286.5 eV and 288.5 eV. do. These are consistent with CC, C-OH, -COOH BE, respectively, commonly reported in the literature. [12] We recently showed that in MXenes, the BE is 282 eV when a C atom is surrounded by six Ti atoms. [13] Here, no peak is seen at 282 eV, consistent with C not being surrounded by six Ti atoms. In our structure, C is bonded to four Ti atoms, so it is not surprising that their BE is higher than 282 eV. After careful consideration, we concluded that our TCO C peak overlaps with an incidental CC peak.

As shown in FIG. 11, the BE of Ti 2p _3/2 is a weak function of processing. For example, the BE after ethanol cleaning, after LiCl treatment, and even after TGA treatment up to 800°C are all comparable, and therefore the values obtained for these films represent the total BE under all processing conditions. can be considered to represent. When the film was heated in air, the XPS spectrum shifted (not shown).

Figure 13 shows that except for the case of _Ti3SiC2 where a Si _signal was observed (Figure 13c), all other films are composed of only three elements, Ti, O, and C. Furthermore, it was confirmed that Cl was not present between the layers, and that a two-layer hydroxide was not being treated (FIG. 13b).

Thermogravimetric analysis, TGA

The sample washed with ethanol and LiCl was placed in a TGA and heated to 800° C. in Ar. The results are shown in FIG. With the notable exceptions of the TiO ₂ -derived film and the ethanol-washed film (two outliers in Figure 14a), the overall weight loss was about 15%. A single LiCl cleaning film from TiC in Ar gave the same results as heating in Ar. However, in this case the TGA was connected to a mass spectrometer and the only gas evolved up to 400 °C was shown to be water (Fig. 14b and c). Above that temperature, some _CO2 was evolved.

_TiO2 is an outlier because XRD and TEM (Fig. 16) showed that it is nanoanatase particles rather than 2D structures that are formed in this case. At this point, it is instructive to compare the XRD diffraction patterns of anatase and our 2D thin sections. In the latter, the (104) and (105) peaks are absent and the 63° 2θ peak of anatase is shifted much closer to 60° 2θ (Fig. 16a).

Rietveld analysis of samples heated to 800°C with TGA

Rietveld analysis (RA) results (Figure 15) of the XRD pattern of FF heated to 800° C. in Ar in TGA were cut out and the fractions of various phases were quantified. The results are shown in Table 8. In most cases, the resulting phases were lithium titanate, LTA, Li _1.33 Ti _1.66 O ₄ and anatase or rutile, TiO ₂ . Most χ ² values were <2, indicating very good fit. Note that the film obtained from _TiO2 is not layered and therefore has the lowest LTA volume fraction.

Atomic force microscope, AFM

To better understand the dimensions and composition of the 2D flakes, we performed AFM studies of 2D flakes and nanoribbons. The results shown in Figure 3c and d confirmed that the obtained 2D flakes were composed of self-aligned nanofilaments.

To obtain nanofilaments, TiC powder was heated in TMAH at 80° C. for 5 days. When this colloidal suspension was spin-coated onto a glass slide at 1000 rpm for 10 seconds, an unmistakable fibrous structure with filaments aligned in approximately the same direction was observed by AFM (Figure 3c). This colloidal suspension was diluted 500 times and drop cast onto a substrate. As a result, the filaments separated (Fig. 3d). Tracing the AFM across the blue line shown in Fig. 3d, the obtained profile showed that the thickness of the thinnest fiber was ≈1.5 nm (inset of Fig. 3d).

Lithium ion battery, LIB

For a lithium ion secondary battery, a CR2032 type coin cell was fabricated, and the electrochemical performance of the Ti ₃ AlC ₂ -derived electrode was investigated. Cyclic voltammetry (CV) curves (inset of Fig. 4b) obtained at a scan rate of 0.1 mVs ⁻¹ in the voltage range of 0.001–3.0 V vs. Li/Li ⁺ can be found in the MXene literature. very similar to a curve. [14,15]

Figure 4b of this paper shows the galvanostatic charge-discharge voltage profile at a specific current of 20 mAg ⁻¹ , with an initial lithiation specific capacity of 714 mAhg and an initial delithiation specific capacity of 265 mAhg ⁻¹ . The specific capacity loss during the initial lithiation process is believed to be due to solid electrolyte interphase (SEI) layer formation below 0.85 V and other irreversible reactions. [16] The specific capacity stabilizes after two cycles. Stable lithiation specific capacity of 210 mAhg and delithiation specific capacity of 209 mAhg ⁻¹ are maintained after 5 cycles. Figure 17a plots the electrochemical impedance spectroscopy of the electrode, showing low system resistance (4 Ω) and small charge transfer resistance (18 Ω), corroborating the observed electrochemical performance. The speed throughput results are shown in Figure 17b. At 500 mAg ⁻¹ , a reversible capacity of ~110 mAhg ⁻¹ can be maintained. Even at 1000 mAg ⁻¹ , a reversible capacity of ~80 mAhg ⁻¹ was achieved, and upon returning to 20 mAg ⁻¹ , the capacity recovered to ~180 mAhg ⁻¹ . As shown in Figure 17c and d, the as-prepared TCO electrode exhibited excellent cycling stability performance at a specific current of 100 mAg ⁻¹ . This electrode exhibited a specific capacity of 155 mAhg ⁻¹ at 200 cycles. Furthermore, the Coulombic efficiency of this electrode was ≈98.9% after 30 cycles, reflecting a highly efficient electrochemical cycle.

Lithium sulfur, Li-S electrode

FIG. 18a plots a typical CV curve in the 1.8-2.6 V (vs. Li/Li ⁺ ) range at a scan rate of 0.1 mV-s ⁻¹ . The CV curve shows two sharp and distinct cathodic peaks and one anodic peak. The first cathodic peak at 2.3 V is due to S reduction to long-chain lithium polysulfides (LiPs) (12), and the second peak is due to the subsequent reduction of LiP to Li ₂ 6/Li ₂ S. Related. [17] The peak shift after the first anodic peak is believed to be due to nucleation/reorganization during LiP redeposition to 12. Figure 4c shows a typical discharge plateau that is consistent with the CV results. The TCO/S composite electrode exhibited capacities of 1300, 1200, and 1050 mAhg ⁻¹ at 0.1, 0.2, and 0.5 C rates, respectively. Such high capacitance may be related to the electrical conductivity of TiCO in combination with surface active sites that may bind LiP. To evaluate the long-term stability of the cathode, a 0.5 C cycle was performed with an S loading of 0.83 mg cm ⁻² . According to FIG. 14b, the initial capacity of the cell is ~1300 mAhg ⁻¹ and stabilizes to ~1000 mAhg ⁻¹ after the first 5 cycles. This initial capacity drop is associated with two conditioning cycles at low rates of 0.1°C and 0.2°C. The composite exhibited a capacity of ~1000 mAhg ⁻¹ after ≈300 cycles with approximately 100% retention. Capacity decreases after 300 cycles. These values are impressive considering that the cathode is a slurry of TCO flakes and commercially available S powder mixed in a mortar and pestle.

mesoscopic material

50 g of TiB ₂ powder was placed in 500 mL of 25% TMAH solution and heated in a polyethylene bottle at 80 °C for 3 days and shaken on a mechanical lab shaker. After 3 days on a shaker, the resulting suspension was allowed to settle and the liquid was decanted. Then 500 mL of ethanol was added to settle the suspension and the liquid was decanted. Ethanol washing was repeated a total of three times.

After decanting the supernatant, the resulting precipitate was washed with 500 mL of 5M LiCl aqueous solution for 4 hours at room temperature. After the second water wash, the supernatant was decanted to obtain a gray precipitate. The precipitate was dried at 40° C. overnight and then manually ground into a fine powder.

The XRD pattern of the powder showed low angle peaks with a d-spacing of 9.4 A, and non-basal peaks at 25° and 48° corresponding to 2D anatase. The peaks of (104) and (105) had disappeared. Some low intensity peaks belonging to unreacted TiB2 precursor remained. An SEM micrograph (FIG. 19) of the obtained powder shows that well-separated mesoporous particles of approximately 10 μm in size were uniformly distributed. Mesoporous particles may be composed of ligaments several microns long and 100 nm or less in diameter. Mesoporous particles can be used, for example, in drug delivery, energy storage, devices, etc. As an example, a therapeutic agent can be attached to a mesoporous particle (eg, adsorption, intercalation, etc.), the particles with attached therapeutic agent can be introduced into a subject, and the therapeutic agent can be delivered to the subject.

References and notes

[1] A.P. Ferris, W.B. Jepson, J. Colloid Interface Sci. 51 (1975) 245-259.

[2] M. Ghidiu, J. Halim, S. Kota, D. Bish, Y. Gogotsi, M.W. Barsoum, Chem.Mater.28 (2016) 3507-3514.

[3] M. Ghidiu, S. Kota, J. Halim, A.W. Sherwood, N. Nedfors, J. Rosen, V.N. Mochalin, M.W. Barsoum, Chem.Mater.29 (2017) 1099-1106.

[4] W.G. Lawrence, J. Am.Ceram 41 (1958) 136-140.

[5] L. Verger, V. Natu, M. Ghidiu, M.W. Barsoum, J. Phys. Chem.C 20044-20050 (2019) 19725-19733.

[6] M.M. Gudarzi, Langmuir 32 (2016) 5058-5068.

[7] G. Lagaly, S. Ziesmer, J. Colloid Interface Sci. 100-102 (2003) 105-128.

[8] T. Missana, A. Adell, J. Colloid Interface Sci. 230 (2000) 150-156.

[9] V. Natu, M. Sokol, L. Verger, M.W. Barsoum, J. Phys. Chem.C 122 (2018) 27745-27753.

[10] M. Ghidiu, M.W. Barsoum, J. Amer.Ceram.Soc. 100 (2017) 5395-5399.

[11] A. Rogalev, F. Wilhelm, Phys. Met.Metallogr. 116 (2015) 1285-1336.

[12] T.L. Barr, S. Seal, J. Vac.Sci. Technol 13 (1995) 1239-1246.

[13] V. Natu, M. Benchakar, C. Canaff, A. Habrioux, S. Celerier, M.W. Barsoum, Matter 4 (2021) 1224-1251.

[14] J. Luo, X. Tao, J. Zhang, Y. Xia, H. Huang, L. Zhang, Y. Gan, C. Liang, W. Zhang, ACS Nano 10 (2016) 2491-2499.

[15] B. Ahmed, D.H. Anjum, M.N. Hedhili, Y. Gogotsi, H.N. Alshareef, Nanoscale 8 (2016) 7580-7587.

[16] M. Naguib, J. Come, B. Dyatkin, V. Presser, P.-L. Taberna, P. Simon, M.W. Barsoum, Y. Gogotsi, Electrochem. commun.16 (2012) 61-64.

[17] A. Manthiram, Y. Fu, S.-H.Chung, C. Zu, Y.-S.Su, Chem.Rev. 114 (2014) 11751-11787.

aspect

The following aspects are illustrative and do not limit the scope of the disclosure or the appended claims.

Aspect 1. A composition comprising a plurality of oxide-based nanofilaments and/or sub-nanofilaments and optionally an amount of carbon. (As described herein, the nanofilaments can include titanium). The composition can be present as a mesoporous powder, the powder particulates comprising oxide-based nanofilaments and/or sub-nanofilaments.

Aspect 2. The composition of embodiment 1, wherein at least some of the nanofilaments and/or sub-nanofilaments have a width in the range of about 3 to about 50 Å. The width can be, for example, about 3 to about 50 Å, about 5 to about 45 Å, about 7 to about 40 Å, about 9 to about 35 Å, about 12 to about 30 Å, about 15 to about 20 Å, and all intermediate values and combinations. could be.

The composition can be constituted in a suspension, for example in a solution, or in an ink, which ink is printable. Regarding inks, the inks can be sprayed, printed, or otherwise applied to the substrate. Inks can include solvents, binders, and the like.

Aspect 3. A composition according to embodiment 2, wherein at least some of the nanofilaments and/or sub-nanofilaments have an average width in the range of about 7 to about 20 Å.

Aspect 4. A composition according to any one of aspects 1 to 3, wherein the nanofilaments and/or sub-nanofilaments define a non-circular cross-section.

Aspect 5. A composition according to embodiment 4, wherein the nanofilaments and/or sub-nanofilaments define a cross-sectional aspect ratio of greater than 1 to about 10. For example, the cross-sectional aspect ratio may be 1.1-10, 1.5-9, 1.8-8, 2.2-7, 2.5-6, 2.8-5, or even 3.2- It can be 4.

Aspect 6. A composition according to embodiment 5, wherein the nanofilaments and/or sub-nanofilaments define a cross-sectional aspect ratio of about 2 to about 5.

Aspect 7. A composition according to any one of aspects 1 to 6, wherein the nanofilaments and/or sub-nanofilaments have an average cross-sectional area in the range of about 10 to about 100 Å ² . For example, the average cross-sectional area ranges from about 10 to about 100 Å ² , about 15 to about 90 Å ² , about 20 to about 80 Å ² , about 30 to about 70 Å ² , about 40 to about 60 Å ² , or about 50 Å ² be able to.

Aspect 8. A composition according to any one of aspects 1 to 7, wherein at least some of the nanofilaments and/or sub-nanofilaments have a length in the range of 1 nm to about 25 μm. The length can be, for example, about 1 nm to about 25 μm, about 10 nm to about 20 μm, about 50 nm to about 10 μm, about 100 nm to about 5 μm, or about 250 nm to about 2 μm.

Aspect 9. A composition according to aspect 8, wherein at least some of the nanofilaments and/or sub-nanofilaments have a length in the range of 1 nm to about 1 μm.

Aspect 10. The composition according to any one of aspects 1 to 9, wherein the nanofilaments and/or sub-nanofilaments are composed of a plurality of flakes; the nanofilaments and/or sub-nanofilaments are capable of self-assembling into flakes. . Without being bound to any particular theory or embodiment, the nanofilaments and/or sub-nanofilaments can be aligned in a plane; can be included, thereby providing a flake that is an ordered stack of nanofilament and/or sub-nanofilament layers. Nanofilaments can self-align.

Aspect 11. 8. The composition of embodiment 7, wherein at least a portion of the plurality of flakes are in a common plane. The thin pieces can be laminated well along the lamination direction. The nanofilaments and/or sub-nanofilaments can result in a typical XRD pattern of a 2D material, ie an XRD pattern in which only one family of planes diffracts. Without being bound to any particular theory or embodiment, nanofilaments and/or sub-nanofilaments can self-assemble into 2D flakes.

Aspect 12. The composition according to any one of aspects 1 to 11, further comprising a pharmaceutically acceptable carrier.

Aspect 13. A composition according to any one of aspects 1 to 12, further comprising one or more materials that are lethal to cancer cells.

Aspect 14. A composition according to any one of aspects 1 to 13, further comprising a binder. Such a binder can be, for example, an adhesive, adhesive, or other matrix material.

Aspect 15. 15. The composition of embodiment 14, wherein the binder comprises a polymer.

Aspect 16. The composition according to any one of aspects 1 to 15, wherein the nanofilaments and/or sub-nanofilaments have an XRD pattern of about 38° and about 55° two theta (2θ) compared to the nano or bulk anatase XRD pattern. A composition exhibiting an XRD pattern showing (104) and (105) peaks reduced in . The disclosed nanofilaments and/or sub-nanofilaments can, in some embodiments, exhibit a Raman spectrum that is very similar to that of bulk anatase, but with an XRD spectrum as described herein. can be different from bulk anatase in terms of

Aspect 17. 17. A device, said device comprising a composition according to any one of aspects 1-16.

Aspect 18. 18. The device of aspect 17, wherein the device includes an electrode.

Aspect 19. 18. The device according to aspect 17, wherein the device is characterized as an energy storage device. Such a device can be, for example, a battery, a supercapacitor, etc. The device may be rechargeable, but disposable. Such devices may consist of mobile computing devices, mobile communication devices, computing devices, lighting devices, signal transmitting devices, signal receiving devices.

Aspect 20. 19. The device according to aspect 18, wherein the electrode comprises a composition according to any one of aspects 1 to 16.

Aspect 21. 18. The device according to aspect 17, wherein the device comprises a dispenser, the dispenser disposing the composition according to any one of aspects 1 to 16 therein. The dispenser can be, for example, a syringe, a nozzle, etc. Such a dispenser may be used to deliver a composition (eg, according to any one of embodiments 1-16) to a subject (eg, a human patient) and/or a sample obtained from the patient. Such a sample may be, for example, a blood sample.

Aspect 22. 18. A method comprising operating an apparatus according to aspect 17.

Aspect 23. A method, wherein the method comprises adding mono, binary, ternary or more carbides, nitrides, borides, phosphides, aluminides, or silicides, or titanium metal to a quaternary ammonium salt and/or contacting with a base, wherein the mono, binary, ternary, or more carbide, nitride, boride, phosphide, aluminide, or silicide, or titanium metal is optionally water-insoluble. , said water-insoluble binary, ternary, or higher carbide, nitride, boride, phosphide, aluminide, or silicide optionally includes a transition metal, and said transition metal optionally includes titanium. and wherein the contacting step is carried out under conditions sufficient to produce a nanofilamentary (and/or subnanofilamentary) product. The product can self-assemble into 2D flakes.

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. Examples of nitrides include 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, and tantalum nitride. , titanium nitride, vanadium nitride, zinc nitride, zirconium nitride.

Examples of borides include aluminum diboride, aluminum dodecoboride, magnesium aluminum boride, barium boride, calcium hexaboride, cerium hexaboride, chromium(III) boride, cobalt boride, Dinickel boride, erbium hexaboride, erbium tetraboride, hafnium diboride, iron boride, iron tetraboride, lanthanum hexaboride, magnesium diboride, nickel boride, niobium diboride, boride Osmium, plutonium boride, rhenium diboride, ruthenium boride, samarium hexaboride, scandium dodecoboride, silicon boride, strontium hexaboride, tantalum boride, titanium diboride, trinickel boride, boron Contains tungsten oxide, uranium diboride, yttrium boride, zirconium diboride, etc.

Examples of phosphides include aluminum gallium phosphide, aluminum gallium phosphide, aluminum phosphide, bismuth phosphide, boron phosphide, cadmium phosphide, calcium monophosphide, calcium phosphide, carbon monophosphide, and phosphorus. Cobalt (II) phosphide, copper (I) phosphide, dysprosium phosphide, erbium phosphide, europium (III) phosphide, ferrophosphor, gadolinium phosphide, gallium arsenide phosphide, gallium indium arsenide antimony phosphide, gallium phosphide, Holmium phosphide, indium arsenide antimony phosphide, gallium phosphide, holmium phosphide, indium gallium arsenide phosphide, indium gallium phosphide, indium phosphide, 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, strontium phosphide, telluride phosphide, terbium phosphide, phosphorus Contains thulium phosphide, titanium (III) phosphide, uranium monophosphide, ytterbium phosphide, yttrium phosphide, zinc diphosphide, zinc cadmium arsenic phosphide, and zinc phosphide.

Examples of aluminides include, for example, magnesium aluminide, titanium aluminide, iron aluminide, and nickel aluminide.

Examples of silicides include, for example, nickel silicide, sodium silicide, magnesium silicide, platinum silicide, titanium silicide, tungsten silicide, and molybdenum silicide.

Without being bound to any particular theory or embodiment, mono, binary, or ternary or higher carbides, nitrides, borides, phosphides, aluminides, or silicides containing titanium are particularly suitable. . Similarly, titanium sponge is believed to be a particularly suitable form of titanium metal for use in the disclosed technology. For example, contacting a titanium sponge with a quaternary ammonium salt, as described herein, to yield a nanofilamentary (or subnanofilamentary) product, as described herein. be able to.

Aspect 24. 24. The method of aspect 23, wherein the conditions include 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 it can also be varied, eg, raised and/or lowered. The temperature is, 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 It can be 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. Temperatures of 100-200°C are also suitable. Although the temperature can be varied during exposure (eg, exposure to a first temperature followed by exposure to a second temperature), this is not a necessary requirement. Exposure can be performed according to a preprogrammed schedule that sets the temperature and/or exposure time, for example. The exposure temperature is, for example, about 25°C, about 30°C, about 35°C, about 40°C, about 45°C, about 50°C, about 55°C, about 60°C, about 65°C, about 70°C, about 75°C, The temperature can be about 80°C, about 90°C, about 95°C, or about 100°C.

The conditions, in some embodiments, include temperatures from about 20 to about 300° C. and exposure for about 0.5 hours to about 2, 3, 4, or 5 weeks. The conditions may include temperatures of about 100 to about 200°C and exposure for about 1 hour to about 1 week. The temperature can be constant during the exposure time, but it can also be varied, eg, raised and/or lowered. The temperature is, 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 The temperature can be 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. Although the temperature can be varied during exposure (eg, exposure to a first temperature followed by exposure to a second temperature), this is not a necessary requirement. Exposure can be performed according to a preprogrammed schedule that sets the temperature and/or exposure time, for example. 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 carried out in a closed system, such as a pressure vessel. The pressure can be atmospheric, but it can also be less than atmospheric, or it can be greater than atmospheric, for example from more than 1 atm (101.325 kPa) to about 10 atm (1013.250 kPa). ) pressure can be used.

The exposure period (which can be referred to as "reaction time") can be, for example, about 1 hour to about 7 days, about 5 hours to about 6 days, about 15 hours to about 5 days, about 20 hours to about 4 days. , about 24 hours to about 3 days, or about 2 days. However, in 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, It can be 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 subcombinations of ranges.

Aspect 25. A method according to embodiment 23, comprising contacting a mono, binary, ternary or more boride (which may include Ti) with a quaternary ammonium salt and/or a base to yield the product. and the product may be nanofilamentary and/or subnanofilamentary.

Aspect 26. 26. The method of embodiment 25, wherein the binary boride comprises one or more titanium borides.

Aspect 27. 27. The method according to any one of aspects 23-26, wherein the quaternary ammonium salt and/or base comprises ammonium hydroxide, ammonium halide, or any combination thereof.

Aspect 28. In the method according to aspect 27, the quaternary ammonium hydroxide is tetramethylammonium hydroxide (TMAOH), tetraethylammonium hydroxide (TEAOH), tetrapropylammonium hydroxide (TPAOH), tetrabutylammonium hydroxide (TBAOH). , ammonium hydroxide ( _NH4OH ), amine derivatives thereof, or any combination thereof.

Aspect 29. The method of embodiment 27, wherein the quaternary ammonium salt comprises quaternary ammonium chloride, quaternary ammonium bromide, quaternary ammonium iodide, quaternary ammonium fluoride, or any combination thereof. ,Method. It should be understood that either or both quaternary ammonium salts and quaternary ammonium bases can be used.

Aspect 30. 30. The method according to any one of aspects 23 to 29, further comprising the step of filtering the product.

Aspect 31. 31. The method according to any one of aspects 23 to 30, further comprising washing the product with metal salts and/or other water-soluble metal compounds.

The metal salt is a halogenated metal salt, for example, a halogenated Li, a halogenated Na, a halogenated K, a halogenated Rb, a halogenated Cs, a halogenated Fr, a halogenated Be, a halogenated Mg, a halogenated Ca, a halogenated Sr, Ba halide, Ra halide, Mn halide, Fe halide, Ni halide, Co halide, Cu halide, Zn halide, Mo halide, Nb halide, W halide, or any thereof It can be a combination of

Aspect 32. A method according to any one of aspects 23 to 31, further comprising washing the product with the metal salt and/or water-soluble metal compound. The metal salt can optionally include a metal sulfate, nitrate, chromate, acetate, carbonate, permanganate, or metal hydroxide, or any combination thereof.

Aspect 33. 33. The method of embodiment 32, wherein the metal in the salt can be essentially any metal from the periodic table. However, as some non-limiting examples, the metal in the metal salt may include Li, Na, K, Cs, Mg, Ca, Cr, Mn, Fe, Co, Ni, Cu, Zn, Nb, Mo, It can be 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.

Aspect 34. The method according to any one of aspects 32-33, wherein the metal salt is LiCl, KCl, NaCl, LiF, CsCl, KF, NaF, LiOH, KOH, NaOH, or any combination thereof. .

Aspect 35. The method according to any one of aspects 32-33, wherein the metal salt is CrCl ₃ , MnCl ₂ , FeCl ₂ , FeCl 3 , CoCl ₂ , NiCl _{2 ,} MoCl ₅ , FeSO ₄ , (NH ₄ ) ₂ Fe ( _SO4 ) ₂ , _CuCl2 , CuCl, _ZnCl2 or any combination thereof.

Aspect 36. A method according to any one of aspects 23 to 35, wherein the product is a composition according to any one of aspects 1 to 16.

Aspect 37. 37. The method of any one of aspects 23-36, wherein the nanofilamentary (and/or subnanofilamentary) product has an XRD pattern of about 38° and about 55° compared to the nano- or bulk anatase XRD pattern. A method showing an XRD pattern exhibiting (104) and (105) peaks reduced to 2-theta (2θ). As described elsewhere herein, the disclosed nanofilaments and/or sub-nanofilaments may, in some embodiments, exhibit Raman spectra similar to that of bulk anatase; As described in the specification, it may differ from bulk anatase with respect to the XRD spectrum.

Aspect 38. A method, the method comprising:

A step of contacting particulate _TiO2 with a quaternary ammonium salt and/or a base, the step comprising:

The contacting step is carried out under conditions sufficient to produce an anatase nanoparticle product;

The nanoparticle product optionally has a diameter of at least some of the nanoparticles from about 2 nm to about 1000 nm, optionally from about 10 nm to about 100 nm.

The nanoparticle product can be further processed, eg, by heating, further reactions, and the like. Further processing can be performed to coarsen the product, for example to produce larger sized particles, such as from about 0.1 to about 0.7 μm, or from about 0.2 to about 0.5 μm. can.

The disclosed method for producing anatase products of the present disclosure provides an alternative to _TiO2 (including pigment grade _TiO2 ) and also provides an alternative to _TiO2 , particularly pigment grade _TiO2 . Provide improvements to existing processes for manufacturing.

More specifically, currently, producing pigment-grade _TiO2 starts with low-grade _TiO2 , chlorinates the low-grade _TiO2 at high temperature to convert the _TiO2 to TiCl4, and converts the latter into _TiCl4 . Oxidize. The disclosed method improves on this cumbersome existing process.

The contacting step includes about 20°C to about 80°C, or about 25°C to about 75°C, or about 30°C to about 70°C, or about 35°C to about 65°C, or about 40°C to about 60°C, Alternatively, it can be carried out at about 45°C to about 55°C, or even at about 50°C. The contacting step may be performed for about 5 minutes to about 5 hours, about 10 minutes to about 4.5 hours, about 15 minutes to about 4 hours, about 20 minutes to about 3.5 hours, about 30 minutes to about 3 hours, for example. time, about 45 minutes to about 2 hours, or any combination or subrange thereof.

Aspect 39. 39. The method of embodiment 38, wherein the quaternary ammonium salt and/or base comprises ammonium hydroxide, ammonium halide, or any combination thereof.

Aspect 40. In the method according to aspect 38, the quaternary ammonium base is tetramethylammonium hydroxide (TMAOH), tetraethylammonium hydroxide (TEAOH), tetrapropylammonium hydroxide (TPAOH), tetrabutylammonium hydroxide (TBAOH), A method comprising ammonium hydroxide ( _NH4OH ), an amine derivative thereof, or any combination thereof.

Aspect 41. 39. The method of embodiment 38, wherein the quaternary ammonium salt comprises quaternary ammonium chloride, quaternary ammonium bromide, quaternary ammonium iodide, quaternary ammonium fluoride, or any combination thereof. ,Method. As described elsewhere herein, either or both quaternary ammonium salts and quaternary ammonium bases can be used.

Aspect 42. 42. The method according to any one of aspects 38-41, further comprising the step of filtering the product.

Aspect 43. A composition comprising a population of anatase nanoparticles produced according to any one of aspects 38-42. Such nanoparticles may be about 200 nm to about 600 nm, such as about 200 nm to about 600 nm, about 225 nm to about 575 nm, about 250 nm to about 550 nm, about 275 nm to about 525 nm, about 300 nm to about 500 nm, about 325 nm to about 475 nm. , about 350 nm to about 450 nm, about 375 nm to about 425 nm, or even about 400 nm.

Aspect 44. A method comprising replacing TiO ₂ with a population of anatase nanoparticles produced according to any one of aspects 38-42. By way of example, pigments typically made with conventional TiO ₂ can be formulated by replacing conventional TiO ₂ with anatase nanoparticles according to the present disclosure, e.g., according to any one of embodiments 38-42. .

Aspect 45. A method, wherein the method comprises adding mono, binary, ternary or more carbides, nitrides, borides, phosphides, aluminides, or silicides, or titanium metal to a quaternary ammonium salt and/or contacting with a base, wherein the mono, binary, ternary, or more carbide, nitride, boride, phosphide, aluminide, or silicide, or titanium metal is optionally water-insoluble. , said water-insoluble binary, ternary, or higher carbide, nitride, boride, phosphide, aluminide, or silicide optionally includes a transition metal, and said transition metal optionally includes titanium. wherein the contacting step is performed with optional shaking, and the contacting step is performed under conditions sufficient to produce mesoporous particles.

Aspect 46. A method, wherein the method comprises adding mono, binary, ternary or more carbides, nitrides, borides, phosphides, aluminides, or silicides, or titanium metal to a quaternary ammonium salt and/or contacting with a base, wherein the mono, binary, ternary, or more carbide, nitride, boride, phosphide, aluminide, or silicide, or titanium metal is optionally water-insoluble. , said water-insoluble binary, ternary, or higher carbide, nitride, boride, phosphide, aluminide, or silicide optionally includes a transition metal, and said transition metal optionally includes titanium. wherein the contacting step is optionally performed with shaking, and the contacting step is followed by washing with at least one salt, and the contacting step is performed under conditions sufficient to produce mesoporous particles. A method, including a process.

Aspect 47. A method, wherein the method comprises adding a mono, binary, ternary or more carbide, nitride, boride, phosphide, aluminide, or silicide, or titanium metal to a quaternary ammonium salt and/or contacting with a base, said mono, binary, ternary or more carbide, nitride, boride, phosphide, aluminide, or silicide, or titanium metal, optionally being insoluble in water; , said water-insoluble binary, ternary, or higher carbide, nitride, boride, phosphide, aluminide, or silicide optionally includes a transition metal, and said transition metal optionally includes titanium. and wherein the contacting step is performed at a temperature of about 50 to about 95° C., optionally with shaking, and then washed with LiCl to yield mesoporous particles.

Aspect 48. A composition comprising mesoporous particles produced according to any one of claims 45 to 47.

Mesoporous particles can exhibit an XRD pattern exhibiting reduced (104) and (105) peaks to about 38° and about 55° 2 theta (2θ) when compared to the XRD pattern of nano or bulk anatase. The disclosed mesoporous particles, in some embodiments, can exhibit a Raman spectrum that is very similar to that of bulk anatase, but as described herein, It can also be different.

Aspect 49. A composition comprising mesoporous particles, the mesoporous particles comprising titanium, wherein the mesoporous particles are reduced to about 38° and about 55° 2 theta (2θ) compared to an XRD pattern of nanoanatase or bulk anatase. A composition exhibiting an XRD pattern exhibiting (104) and (105) peaks. The disclosed mesoporous particles, in some embodiments, can exhibit a Raman spectrum that is very similar to that of bulk anatase, but as described herein, It can also be different.

Aspect 50. 50. The composition of any one of claims 48-49, further comprising a therapeutic agent.

Aspect 51. 50. A method comprising delivering a therapeutic agent to a subject, the therapeutic agent being comprised in a composition according to any one of claims 48-49.

Aspect 52. An electrode, said electrode comprising a composition according to any one of claims 48 to 49.

Aspect 53. A device, said device comprising a composition according to any one of claims 48-49.

Aspect 54. 53. The device of claim 52, wherein the device is an energy storage device.

Aspect 55. A method comprising the step of operating an apparatus according to any one of claims 52-53.

Claims (60)

A composition comprising a plurality of metal oxide sub-nanofilaments and/or nanofilaments and optionally an amount of carbon. The composition of claim 1, wherein at least some of the nanofilaments and/or sub-nanofilaments have a width in the range of about 3 to about 50 Å. The composition of claim 2, wherein at least some of the nanofilaments and/or sub-nanofilaments have an average width in the range of about 7 to about 20 Å. A composition according to claim 1, wherein the nanofilaments and/or sub-nanofilaments define a non-circular cross section. 5. The composition of claim 4, wherein the nanofilaments and/or sub-nanofilaments define a cross-sectional aspect ratio of greater than 1 to about 10. 6. The composition of claim 5, wherein the nanofilaments and/or sub-nanofilaments define a cross-sectional aspect ratio of about 2 to about 5. The composition of claim 1, wherein the nanofilaments and/or sub-nanofilaments have an average cross-sectional area in the range of about 10 to about 100 Å ² . The composition of claim 1, wherein at least some of the nanofilaments and/or sub-nanofilaments have a length in the range of 1 nm to about 25 μm. A composition according to claim 8, wherein at least some of the nanofilaments and/or sub-nanofilaments have a length in the range of 1 nm to about 1 μm. A composition according to claim 1, wherein the nanofilaments and/or sub-nanofilaments are comprised of a plurality of flakes. 8. The composition of claim 7, wherein at least a portion of the plurality of nanofilaments and/or sub-nanofilaments are in a common plane. A composition according to any one of claims 1 to 11, further comprising a pharmaceutically acceptable carrier. 7. The composition of claim 1, further comprising one or more substances lethal to cancer cells. 2. The composition of claim 1, further comprising a binder. 15. The composition of claim 14, wherein the binder comprises a polymer. The composition of claim 1, wherein the nanofilament exhibits an XRD pattern that exhibits reduced (104) and (105) peaks to about 38° and about 55° 2-theta compared to bulk or nanoanatase XRD patterns. A composition showing. A device comprising the composition of claim 1. 18. The device of claim 17, wherein the device includes an electrode. 18. Device according to claim 17, characterized in that the device is an energy storage device. 19. The device of claim 18, wherein the electrode comprises the composition of claim 1. 18. The device of claim 17, wherein the device includes a dispenser, the dispenser disposing the composition of claim 1 therein. 18. A method comprising operating the apparatus of claim 17. A method, the method comprising:
contacting a mono, binary, ternary, or more carbide, nitride, boride, phosphide, aluminide, or silicide, or titanium metal with a quaternary ammonium salt and/or a base;
The mono, binary, ternary, or more carbide, nitride, boride, phosphide, aluminide, or silicide, or titanium metal is optionally water-insoluble;
The water-insoluble binary, ternary, or higher carbide, nitride, boride, phosphide, aluminide, or silicide optionally includes a transition metal, and the transition metal optionally includes titanium. ,
the contacting step is carried out under conditions sufficient to produce a nanofilamentary product;
Method. 24. The method of claim 23, wherein the conditions include temperatures from 0 to 100° C. for about 5 hours to about 1 week. 24. The method of claim 23, comprising contacting the mono, binary, ternary or more boride with a quaternary ammonium salt and/or a base to produce a nanofilamentary product. . 26. The method of claim 25, wherein the binary boride comprises one or more titanium borides. 24. The method of claim 23, wherein the quaternary ammonium salt and/or base comprises ammonium hydroxide, ammonium halide, or any combination thereof. 28. The method of claim 27, wherein the quaternary ammonium hydroxide is tetramethylammonium hydroxide (TMAOH), tetraethylammonium hydroxide (TEAOH), tetrapropylammonium hydroxide (TPAOH), tetrabutylammonium hydroxide (TBAOH). ), ammonium hydroxide ( _NH4OH ), amine derivatives thereof, or any combination thereof. 28. The method of claim 27, wherein the quaternary ammonium salt comprises quaternary ammonium chloride, quaternary ammonium bromide, quaternary ammonium iodide, quaternary ammonium fluoride, or any combination thereof. Including, methods. 24. The method of claim 23, further comprising filtering the product. 24. The method of claim 23, further comprising washing the product with metal salts and/or other water-soluble metal compounds. 24. The method of claim 23, further comprising washing the product with a metal salt and/or a water-soluble metal compound, wherein the metal salt is optionally a metal sulfate, a metal nitrate, a metal chromate, a metal acetate. , metal carbonate, metal permanganate, or metal hydroxide, or any combination thereof. 33. The method according to claim 32, wherein the metal in the metal salt is Li, Na, K, Cs, Mg, Ca, Cr, Mn, Fe, Co, Ni, Cu, Zn, Nb, Mo, Cd, Ta, or W, or any combination thereof. 33. The method of claim 32, wherein the metal salt comprises LiCl, KCl, NaCl, CsCl, LiF, KF, NaF, LiOH, KOH, NaOH, or any combination thereof. 33. The method of claim 32, wherein the metal salt is _CrCl3 , _MnCl2 , _FeCl2 , _FeCl3 , CoCl2, _{NiCl2 , MoCl5} , _FeSO4 , ( _NH4 ) _2Fe ( _SO4 ) ₂ , CuCl2. ₂ , CuCl, _ZnCl2 or any combination thereof. 24. The method of claim 23, wherein the product is the composition of claim 1. 24. The method of claim 23, wherein the nanofilamentary product exhibits reduced (104) and (105) peaks to about 38° and about 55° 2-theta compared to nano or bulk anatase XRD patterns. A method of presenting two-dimensional XRD patterns. A method, the method comprising:
contacting the particulate _TiO2 with a quaternary ammonium salt and/or a base;
the contacting step is carried out under conditions sufficient to produce anatase nanoparticle products;
The nanoparticle product optionally has at least some nanoparticles having a diameter of about 2 nm to about 1000 nm, optionally about 10 to about 100 nm.
Method. 39. The method of claim 38, wherein the quaternary ammonium salt and/or base comprises ammonium hydroxide, ammonium halide, or any combination thereof. 39. The method of claim 38, wherein the quaternary ammonium base is tetramethylammonium hydroxide (TMAOH), tetraethylammonium hydroxide (TEAOH), tetrapropylammonium hydroxide (TPAOH), tetrabutylammonium hydroxide (TBAOH). , ammonium hydroxide ( _NH4OH ), amine derivatives thereof, or any combination thereof. 39. The method of claim 38, wherein the quaternary ammonium salt, together with the base, is a quaternary ammonium chloride, a quaternary ammonium bromide, a quaternary ammonium iodide, a quaternary ammonium fluoride, or any thereof. A method, including a combination of. 39. The method of claim 38, further comprising filtering the product. 39. A composition comprising a population of anatase nanoparticles produced according to claim 38. 39. A method comprising replacing _TiO2 with a population of anatase nanoparticles produced according to claim 38. A method, the method comprising:
contacting a mono, binary, ternary, or more carbide, nitride, boride, phosphide, aluminide, or silicide, or titanium metal with a quaternary ammonium salt and/or a base;
The mono, binary, ternary, or more carbide, nitride, boride, phosphide, aluminide, or silicide, or titanium metal is optionally water-insoluble;
The water-insoluble binary, ternary, or higher carbide, nitride, boride, phosphide, aluminide, or silicide optionally includes a transition metal, and the transition metal optionally includes titanium. ,
The contacting step is optionally performed with shaking, and
The contacting step is carried out under conditions sufficient to produce mesoporous particles.
Method. A method, the method comprising:
contacting a mono, binary, ternary, or more carbide, nitride, boride, phosphide, aluminide, or silicide, or titanium metal with a quaternary ammonium salt and/or a base;
The mono, binary, ternary, or more carbide, nitride, boride, phosphide, aluminide, or silicide, or titanium metal is optionally water-insoluble;
The water-insoluble binary, ternary, or higher carbide, nitride, boride, phosphide, aluminide, or silicide optionally includes a transition metal, and the transition metal optionally includes titanium. ,
The contacting step is performed with optional shaking, and the contacting step is followed by washing with at least one salt and performed under conditions sufficient to produce mesoporous particles.
Method. A method, the method comprising:
contacting a mono, binary, ternary, or more carbide, nitride, boride, phosphide, aluminide, or silicide, or titanium metal with a quaternary ammonium salt and/or a base;
The mono, binary, ternary, or more carbide, nitride, boride, phosphide, aluminide, or silicide, or titanium metal is optionally water-insoluble;
The water-insoluble binary, ternary, or higher carbide, nitride, boride, phosphide, aluminide, or silicide optionally includes a transition metal, and the transition metal optionally includes titanium. ,
The contacting step is carried out at a temperature of about 50 to about 95° C. with shaking, followed by washing with LiCl, resulting in mesoporous particles.
Method. A composition comprising mesoporous particles produced according to any one of claims 45 to 47. A composition comprising mesoporous particles, the mesoporous particles comprising titanium, the mesoporous particles having an XRD pattern reduced to about 38° and about 55° 2 theta (2θ) as compared to a nano or bulk anatase XRD pattern. A composition exhibiting an XRD pattern exhibiting (104) and (105) peaks. 49. The composition of claim 48, further comprising a therapeutic agent. 50. The composition of claim 49, further comprising a therapeutic agent. 49. A method, said method comprising delivering a therapeutic agent to a subject, said therapeutic agent being comprised in the composition of claim 48. 50. A method, said method comprising delivering a therapeutic agent to a subject, said therapeutic agent being comprised in the composition of claim 49. 50. An electrode, the electrode comprising the composition of claim 48. 50. An electrode, the electrode comprising the composition of claim 49. 50. A device, the device comprising the composition of claim 48. 50. A device, the device comprising the composition of claim 49. 58. The apparatus of claim 56 or claim 57, wherein the device is an energy storage device. 58. A method comprising operating the apparatus of claim 57. 60. A method comprising operating the apparatus of claim 58.

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