CN114318856A - Antibacterial fiber, preparation method and application - Google Patents

Abstract

The invention discloses an antibacterial fiber, comprising a fabric fiber and an antibacterial coating covering the outer surface of the fabric fiber. The antibacterial coating includes transition metal carbide and bismuth oxyhalide; the transition metal carbide is a layer The bismuth oxyhalide is a nanosheet array distributed on the surface of the transition metal carbide; the bismuth ions in the bismuth oxyhalide and the transition metal carbide are adsorbed and combined by electrostatic force, A heterogeneous interface is formed between the bismuth oxyhalide and the transition metal carbide. Also disclosed is a preparation method for antibacterial fibers, including: fabric fiber pretreatment; transition metal carbide preparation; preparation of transition metal carbide coating; preparation of bismuth oxyhalide-transition metal carbide coating; and also including hydrophobic coating preparation. The bismuth oxyhalide-transition metal carbide coating is formed on the surface of the fabric fiber at room temperature, which gives the fabric rapid antibacterial ability without destroying the comfort and safety of the fabric.

Description

A kind of antibacterial fiber, preparation method and application

technical field

The invention belongs to the technical field of material engineering, and in particular relates to an antibacterial fiber, a preparation method and an application.

Background technique

With the improvement of quality of life, people pay more attention to the management of self-health, and the performance of fabrics has become the focus of attention. Especially the fabrics of medical staff, bacterial contamination will occur within a few hours, so that bacteria can quickly spread between patients, resulting in cross-infection between patients. At present, antibacterial fabrics mainly use traditional organic antibacterial agents such as silver or silver ions, quaternary ammonium and natural antibacterial agents. The antibacterial effect of silver and silver ions will cause toxicity to the environment and the human body. The stability of organic antibacterial agents is poor, which may cause potential physiological effects on the human body. The antibacterial effect of natural antibacterial agents is poor. In addition, the bactericidal effect of these antibacterial agents takes a long time and the effect is poor. Therefore, the development of safe bactericides with rapid sterilization and hydrophobicity has potential research value.

Recently, exogenous excitation can be used to generate photothermal and photodynamic materials, in which photothermal can effectively destroy bacterial membranes and accelerate bacterial death. The free radicals generated by photodynamics can cause oxidative damage to bacteria, affect the metabolism of bacteria, and reduce the activity of bacteria. The synergistic effect of photothermal and photodynamics can kill and kill bacteria efficiently and quickly in a short time. At the same time, this sterilization method has spectral antibacterial properties. The fabric will inevitably be exposed to sunlight, therefore, the use of sunlight to sterilize must become the best choice for antibacterial fabrics.

Bismuth oxybromide (BiOBr) is an indirect bandgap semiconductor with a suitable visible-light-responsive bandgap and exhibits good photocatalytic performance. However, the photogenerated carriers of a single BiOBr have a low transfer rate and a high recombination rate. In addition, its low conduction band potential is not conducive to the reduction of photogenerated electrons to generate superoxide radicals, thus limiting the improvement of its photocatalytic activity. Bismuth oxybromide has poor light absorption and no photothermal effect under visible light, these limitations limit its further applications. As a new type of two-dimensional layered material, titanium carbide has excellent electrical conductivity and light absorption capacity, and its excellent photothermal conversion efficiency expands the further application of the material. High temperatures are maintained for extended periods of time, which may affect the durability of the fabric. In addition, titanium carbide is extremely unstable in the air, and is easily oxidized to titanium dioxide by water in the air, reducing the photothermal properties of the material.

The above-mentioned prior art has the following shortcomings;

1. Most of the antibacterial fabrics are sterilized by traditional ion release, which has poor biological safety and will cause potential toxicity to the human body;

2. The cost of antibacterial fabrics is high, the antibacterial effect is poor, and it takes a long time;

3. The antibacterial coating mostly adopts high temperature and other conditions, which affects the original performance of the fabric;

4. The single use of bismuth oxybromide or titanium carbide as an antibacterial agent has poor effect and is unstable.

SUMMARY OF THE INVENTION

The object of the present invention is to overcome the deficiencies of the prior art and provide a kind of antibacterial fiber, which is to form a bismuth oxyhalide-transition metal carbide-hydrophobic antibacterial coating on the surface of the fiber under normal temperature conditions, without destroying the comfort of the fabric, On the basis of safety, the fabric is given rapid antibacterial ability, and antibacterial includes bactericidal and bacteriostatic properties.

The present invention is achieved through the following technical solutions:

An antibacterial fiber, comprising a fabric fiber and an antibacterial coating covering the outer surface of the fabric fiber, the antibacterial coating comprising a transition metal carbide and a bismuth oxyhalide; the transition metal carbide is a layered nanostructure or A sheet-like nanostructure, the bismuth oxyhalide is distributed on the surface of the transition metal carbide in the form of a nanosheet array; the bismuth ions in the bismuth oxyhalide and the transition metal carbide are combined by electrostatic force adsorption, the halogenated A heterogeneous interface is formed between the bismuth oxyhalide and the transition metal carbide; the loading amount of the transition metal carbide nanosheet on the fiber is 0.5-1.5 mg/cm ² , and the loading amount of the bismuth oxyhalide on the fiber is 0.5 ~1.5 mg/cm ² .

The material of the fabric fiber is one or more of cotton, polyester, nylon, spandex, acrylic or silk;

The transition metal carbide is one or more of titanium carbide, niobium carbide, vanadium carbide, tantalum carbide or molybdenum carbide;

The bismuth oxyhalide is one or more of bismuth oxychloride, bismuth oxybromide or bismuth oxyiodide.

In the above technical solution, when the transition metal carbide is a layered nanostructure, the number of layers is 1 to 5 layers.

In the above technical solution, the size of the transition metal carbide is 1-5 μm.

In the above technical solution, the size of the bismuth oxyhalide is 300-800 nm.

An antibacterial fiber, comprising a fabric fiber, an antibacterial coating coated on the outer surface of the fabric fiber, and a hydrophobic layer coated on the outside of the antibacterial coating, the antibacterial coating comprising transition metal carbide and bismuth oxyhalide; The transition metal carbide is a layered nanostructure or a sheet nanostructure, and the bismuth oxyhalide is distributed on the surface of the transition metal carbide in the form of a nanosheet array; the bismuth ions in the bismuth oxyhalide and the transition metal carbide The bismuth oxyhalide and the transition metal carbide form a heterogeneous interface through electrostatic adsorption and bonding; the loading amount of the transition metal carbide nanosheet on the fiber is 0.5-1.5 mg/cm ² , and the The loading amount of bismuth oxyhalide on the fiber is 0.5-1.5 mg/cm ² ;

The material of the fabric fiber is one or more of cotton, polyester, nylon, spandex, acrylic or silk;

The transition metal carbide is one or more of titanium carbide, niobium carbide, vanadium carbide, tantalum carbide or molybdenum carbide;

The bismuth oxyhalide is one or more of bismuth oxyfluoride, bismuth oxychloride, bismuth oxybromide or bismuth oxyiodide;

The hydrophobic layer is composed of one or more of polydimethylsiloxane, hexadecyltrimethoxysilane or ethyl orthosilicate, and has a thickness of 10-80 nm.

Another object of the present invention is to provide a preparation method of antibacterial fibers.

A preparation method of antibacterial fiber, comprising the following steps:

Step 1, fabric fiber pretreatment:

The fabric fibers are placed in an alkaline solution with a pH of 11-13, soaked for more than 2 hours, the soaked fabric fibers are washed to remove residual alkali, and the pretreated fabric fibers are obtained after drying;

The material of the fabric fiber is one or more of cotton, polyester, nylon, spandex, acrylic or silk;

Step 2, preparation of transition metal carbide:

The transition metal aluminum carbide is placed in a hydrofluoric acid solution, stirred at 30-40° C., and the soaked transition metal aluminum carbide is washed and dried to obtain the transition metal carbide;

The concentration of the hydrofluoric acid solution is 20-40 wt %, and the lithium ion content is 30-50 mg/mL;

The transition metal is one or more of titanium, niobium, vanadium, tantalum or molybdenum;

The transition metal carbide is a layered nanostructure or a flake nanostructure, and when the transition metal carbide is a layered nanostructure, the number of layers is 1-5;

Step 3, preparation of transition metal carbide coating:

The transition metal carbide prepared in the second step and the pretreated fabric fibers obtained in the first step are placed in water, and a first slurry is obtained by stirring; the fabric fibers are taken out from the first slurry, washed and dried. A fabric fiber with a transition metal carbide coating is obtained;

The mass ratio of the transition metal carbide to the pretreated fabric fiber is 1:20-50; the content of the transition metal carbide in the first slurry is 1-3 mg/L;

Step 4, prepare bismuth oxyhalide-transition metal carbide coating:

The fabric fibers with the transition metal carbide coating prepared in step 3 and the Bi precursor are added to ethylene glycol, and a second slurry is obtained by stirring; the Bi precursor is a ethylene glycol-soluble containing The salt of Bi ³⁺ ; the mass ratio of the fabric fiber with the transition metal carbide coating and the Bi precursor is 1:4-8; the content of the Bi precursor in the second slurry is 20-50 mg/L ;

Add halide to the second slurry, and continue to stir for 0.5-1.5h, the mass ratio of adding the halide and Bi precursor is 1:4-6; take out the fabric fibers from the second slurry, After washing and drying, a fabric fiber with a bismuth oxyhalide-transition metal carbide coating is obtained, and the fabric fiber with a bismuth oxyhalide-transition metal carbide coating has an antibacterial effect;

The halide is a sodium or potassium salt of a halogen element, preferably KBr, NaBr, KCl, NaCl, KI or NaI.

In the above technical solution, in the fourth step, the Bi precursor is Bi ³⁺ salts soluble in ethylene glycol, such as Bi(NO ₃ ) ₃ ·5H ₂ O, BiCl ₃ , and bismuth acetate.

In the above-mentioned technical scheme, also comprises step 5, hydrophobic coating is prepared:

Immerse the fabric fiber with the bismuth oxyhalide-transition metal carbide coating prepared in step 4 in a hydrophobic organic solvent for 2 to 5 hours, take it out, wash and dry to obtain a hydrophobic antibacterial fiber;

The hydrophobic organic solvent is one or more of polydimethylsiloxane, hexadecyltrimethoxysilane, and ethyl orthosilicate.

In the above technical solution, the stirring rate of the stirring is 500-5000 rpm.

In the above technical scheme, step 1, fabric fiber pretreatment: the fabric fiber is placed in an alkaline solution with a pH of 11.5-12.7, soaked for more than 2 hours, the soaked fabric fiber is washed to remove residual alkali, and then placed in an alkaline solution without In water ethanol, ultrasonic cleaning was performed for 30 min, and the pretreated fabric fibers were obtained after drying.

In the above-mentioned technical scheme, step 2, transition metal carbide is prepared:

The transition metal aluminum carbide is placed in a hydrofluoric acid solution, stirred at 30-40° C., the soaked transition metal aluminum carbide is washed and dried, and the transition metal carbide is prepared by ultrasonication;

Another object of the present invention is to provide an application of antibacterial fibers.

An application of the above-mentioned antibacterial fibers in a textile textile process.

A garment prepared from the above-mentioned antibacterial fibers.

The advantages and beneficial effects of the present invention are:

1. The most common sunlight is used as the external light source for antibacterial fabrics, which is universal to different fabrics. The bismuth oxyhalide-transition metal carbide coating is formed on the surface of the fabric fiber at room temperature, which gives the fabric rapid antibacterial ability without destroying the comfort and safety of the fabric. Antibacterial includes bactericidal and bacteriostatic properties.

2. Pure titanium carbide has only excellent photothermal conversion efficiency, poor sterilization effect under light, and takes a long time. A single bismuth oxyhalide can only generate a small amount of free radicals under sunlight, and it is almost difficult to achieve antibacterial effect. In the combination of the two, titanium carbide improves the light absorption capacity of the composite material, which makes the bismuth oxyhalide generate more electron-hole pairs, promotes the separation of electron-hole pairs, and improves the utilization efficiency of photogenerated carriers. Greatly increased the production of free radicals. The bismuth oxyhalide-transition metal carbide coating has excellent photodynamic and photothermal effects, and can achieve the effect of rapid sterilization.

3. The bismuth oxyhalide-transition metal carbide coating can generate heat and free radicals under visible light. Under the synergistic effect of the two, it can achieve high-efficiency sterilization and endow the fabric with high-efficiency antibacterial function.

4. Add a hydrophobic coating on the surface of the antibacterial coating, so that the titanium carbide can reduce the contact with the air, improve the stability of the titanium carbide, and also inhibit the adhesion of bacteria and increase the antibacterial ability of the coating.

5. The preparation method of bismuth oxyhalide-transition metal carbide coating-hydrophobic coating is simple and easy to operate, no toxic and harmful gases are generated, economical and environmental protection, low implementation difficulty, low equipment investment, and low consumption of resources. The traditional antibacterial use is For precious metals such as silver and copper, the technical solution of the present invention uses materials with lower cost.

In a word, in the technical solution of the present invention, the application of sunlight is a light source that the fabric fibers must come into contact with. By constructing a coating that can respond to sunlight on the surface of the fabric fibers, the material exhibits excellent sterilization performance under sunlight. The coating on the surface of the fabric fiber will form a rough nanostructure on the surface, and then modify the low surface energy substances on the surface of the rough material, and further form a hydrophobic coating on the surface of the material, reduce the adhesion of the fabric surface to bacteria, improve the Antibacterial properties of fabric surfaces.

Description of drawings

1 is (a) a scanning electron microscope image of Cotton in Example 1; (b) a high-magnification scanning electron microscope image of Cotton in Example 1; (c) Low-power scanning of Cotton-Ti ₃ C ₂ in Example 1 Electron microscope image; (d) high magnification scanning electron microscope image of Cotton- _Ti3C2 in Example ₁ ; (e) low magnification scanning electron microscope image of Cotton-BiOBr; (f) high magnification scanning electron microscope image of Cotton-BiOBr (g) Low magnification scanning electron microscope image of Cotton-Ti ₃ C ₂ -BiOBr in Example 1; (h) High magnification scanning electron microscope image of Cotton-Ti ₃ C ₂ -BiOBr in Example 1; (i) Implementation Low magnification scanning electron microscope image of Cotton-Ti ₃ C ₂ -BiOBr-PDMS in Example 1; (j) High magnification scanning electron microscope image of Cotton-Ti ₃ C ₂ -BiOBr-PDMS in Example 1.

Figure 2 is (a) a low-magnification scanning electron microscope image of PET in Example 2; (b) a high-magnification scanning electron microscope image of PET in Example 2; (c) low-magnification scanning of PET-Ti ₃ C ₂ in Example 2 Electron microscope image; (d) high magnification SEM image of PET-Ti ₃ C ₂ in Example 2; (e) low magnification SEM image of PET-BiOBr; (f) high magnification SEM image of PET-BiOBr; ( g) Low magnification scanning electron microscope image of PET-Ti ₃ C ₂ -BiOBr in Example 2; (h) High magnification scanning electron microscope image of PET-Ti ₃ C ₂ -BiOBr in Example 2; (i) Example 2 Low magnification scanning electron microscope image of PET-Ti ₃ C ₂ -BiOBr-PDMS in medium; (j) high magnification scanning electron microscope image of PET-Ti ₃ C ₂ -BiOBr-PDMS in Example 2.

3 is a scanning electron microscope image and a surface distribution diagram of Cotton, Cotton-Ti ₃ C ₂ , Cotton-BiOBr and Cotton-Ti ₃ C ₂ -BiOBr in Example 1. FIG.

4 is a scanning electron microscope image and a surface distribution diagram of PET, PET-Ti ₃ C ₂ , PET-BiOBr and PET-Ti ₃ C ₂ -BiOBr in Example 2. FIG.

Figure 5 is a transmission electron microscope image of the Ti ₃ C ₂ -BiOBr coating on the fiber surface.

FIG. 6 is a contact angle comparison diagram of Cotton, Cotton-Ti ₃ C ₂ , Cotton-BiOBr, Cotton-Ti ₃ C ₂ -BiOBr and Cotton-Ti ₃ C ₂ -BiOBr-PDMS obtained in Example 1. FIG.

7 is a contact angle diagram of PET, PET-Ti ₃ C ₂ , PET-BiOBr, PET-Ti ₃ C ₂ -BiOBr and PET-Ti ₃ C ₂ -BiOBr-PDMS.

8 is a photothermal map of Cotton, Cotton-Ti ₃ C ₂ , Cotton-BiOBr, Cotton-Ti ₃ C ₂ -BiOBr and Cotton-Ti ₃ C ₂ -BiOBr-PDMS under simulated sunlight.

9 is a photothermal map of PET, PET-Ti ₃ C ₂ , PET-BiOBr, PET-Ti ₃ C ₂ -BiOBr and PET-Ti ₃ C ₂ -BiOBr-PDMS under simulated sunlight.

FIG. 10 is an antibacterial image of Cotton, Cotton-Ti ₃ C ₂ , Cotton-BiOBr, Cotton-Ti ₃ C ₂ -BiOBr and Cotton-Ti ₃ C ₂ -BiOBr-PDMS under dark and simulated sunlight.

11 is an antibacterial image of PET, PET-Ti ₃ C ₂ , PET-BiOBr, PET-Ti ₃ C ₂ -BiOBr and PET-Ti ₃ C ₂ -BiOBr-PDMS in the dark and under simulated sunlight.

For those of ordinary skill in the art, other related drawings can be obtained from the above drawings without any creative effort.

Detailed ways

In order to make those skilled in the art better understand the solutions of the present invention, the technical solutions of the present invention are further described below with reference to specific embodiments.

Example 1

Step 1, pretreatment of cotton cloth:

Arrange 32cm ² cotton in 100mL 0.1mol/L sodium hydroxide solution, soak for 2 hours, and repeatedly wash the soaked cotton cloth in deionized water to remove residual alkali. The above-mentioned fabrics were placed in absolute ethanol, ultrasonically cleaned for 30 min, and dried to obtain experimental cotton cloth (Cotton) for later use.

Step 2, the preparation of titanium carbide:

1 g of titanium aluminum carbide was placed in a mixed solution of 1 g of lithium fluoride and 12 mol/L of 20 mL of hydrochloric acid, and stirred in a water bath at 40 °C for 24 h at a stirring speed of 800 rpm. Wash with deionized water to pH 6, add a small amount of water, ultrasonicate for 2h at 800W, centrifuge at 3500rpm, take the supernatant to obtain a few-layer or single-layer titanium carbide slurry. It is easier to prepare 1-5 layers of titanium carbide slurry by intercalation of titanium carbide.

Step 3, Preparation of Titanium Carbide Coating

The experimental cotton was placed in a 3 mol/L titanium carbide slurry, stirred for 1 h, the cotton cloth was taken out, washed with water to remove unbound titanium carbide, and then the cotton cloth was freeze-dried to obtain a titanium carbide-coated cotton fabric (Cotton-Ti _{3 )} . _C2 ).

Step 4, Preparation of Bismuth Oxybromide/Titanium Carbide Coating

The above-mentioned titanium carbide-coated cotton fabric was immersed in 10 mL of ethylene glycol and stirred, 480.07 mg Bi(NO ₃ ) ₃ ·5H ₂ O was added, stirred evenly to disperse it, stirred for 0.5 h, and 10 mL of 0.1 mol/L KBr, and continued stirring for 1 h. The cotton cloth was taken out, washed and dried to obtain a bismuth oxybromide-titanium carbide-coated cotton fabric (Cotton-Ti ₃ C ₂ -BiOBr). This room temperature preparation method is simple and feasible, and the most important thing is that titanium carbide is not easily oxidized, and can better exert its excellent electrical conductivity.

Step 5, Preparation of Bismuth Oxybromide/Titanium Carbide/Hydrophobic Coating

Immerse the cotton fabric coated with bismuth oxybromide/titanium carbide in hydrophobic polydimethylsiloxane, soak for 2 hours, take it out, wash and dry to obtain bismuth oxybromide/titanium carbide/polydimethylsiloxane Coated cotton fabric (Cotton-Ti3C2 _{- BiOBr} -PDMS).

Embodiment 2

Step 1, pretreatment of polyester:

Place 32cm ² polyester in 100mL 0.1mol/L sodium hydroxide solution, soak for 2 hours, and repeatedly wash the soaked cotton cloth in deionized water to remove residual alkali. The above fabrics were then placed in absolute ethanol, ultrasonically cleaned for 30 min, and dried to obtain experimental polyester (PET) for later use.

Step 2, the preparation of titanium carbide:

1 g of titanium aluminum carbide was placed in a mixed solution of 1 g of lithium fluoride and 12 mol/L of 20 mL of hydrochloric acid, and stirred in a water bath at 40 °C for 24 h at a stirring speed of 800 rpm. Wash with deionized water to pH 6, add a small amount of water, sonicate at 800W for 2h, centrifuge at 3500rpm, and take the supernatant to obtain a few-layer or single-layer titanium carbide slurry.

Step 3, Preparation of Titanium Carbide Coating

The polyester used in the experiment was placed in a 3 mol/L titanium carbide slurry, stirred for 1 h, the polyester was taken out, washed with water to remove unbound titanium carbide, and then the polyester was freeze-dried to obtain a titanium carbide-coated polyester fabric (PET-Ti _{3 )} . _C2 ).

Step 4, Preparation of Bismuth Oxybromide/Titanium Carbide Coating

The above-mentioned titanium carbide-coated polyester fabric was immersed in 10 mL of ethylene glycol and stirred, 480.07 mg of Bi(NO ₃ ) ₃ ·5H ₂ O was added, stirred evenly to disperse it, stirred for 0.5 h, and 10 mL of 0.1 mol/L KBr, and continued stirring for 1 h. The cotton cloth was taken out, washed and dried to obtain a bismuth oxybromide-titanium carbide-coated polyester fabric (PET-Ti ₃ C ₂ -BiOBr).

Step 5, Preparation of Bismuth Oxybromide/Titanium Carbide/Hydrophobic Coating

Dip the bismuth oxybromide/titanium carbide coated polyester fabric in hydrophobic polydimethylsiloxane for 2 hours, take it out, wash and dry to obtain bismuth oxybromide/titanium carbide/polydimethylsiloxane Coated polyester fabric (PET-Ti3C2 _{- BiOBr} -PDMS).

Embodiment 3

Step 1, pretreatment of cotton cloth:

Arrange 32cm ² cotton in 100mL 0.1mol/L sodium hydroxide solution, soak for 2 hours, and repeatedly wash the soaked cotton cloth in deionized water to remove residual alkali. The above-mentioned fabrics were placed in absolute ethanol, ultrasonically cleaned for 30 min, and dried to obtain experimental cotton cloth (Cotton) for later use.

Step 2, the preparation of titanium carbide:

1 g of titanium aluminum carbide was placed in a mixed solution of 1 g of lithium fluoride and 12 mol/L of 20 mL of hydrochloric acid, and stirred in a water bath at 40 °C for 24 h at a stirring speed of 800 rpm. Wash with deionized water to pH 6, add a small amount of water, sonicate at 800W for 2h, centrifuge at 3500rpm, and take the supernatant to obtain a few-layer or single-layer titanium carbide slurry.

Step 3, Preparation of Titanium Carbide Coating

The experimental cotton was placed in a 3 mol/L titanium carbide slurry, stirred for 1 h, the cotton cloth was taken out, washed with water to remove unbound titanium carbide, and then the cotton cloth was freeze-dried to obtain a titanium carbide-coated cotton fabric (Cotton-Ti _{3 )} . _C2 ).

Step 4, Preparation of Bismuth Oxybromide/Titanium Carbide Coating

The above-mentioned titanium carbide-coated cotton fabric was immersed in 10 mL of ethylene glycol and stirred, 480.07 mg Bi(NO ₃ ) ₃ ·5H ₂ O was added, stirred evenly to disperse it, stirred for 0.5 h, and 10 mL of 0.1 mol/L KBr, and continued stirring for 1 h. The cotton cloth was taken out, washed and dried to obtain a bismuth oxybromide-titanium carbide-coated cotton fabric (Cotton-Ti ₃ C ₂ -BiOBr).

Step 5, Preparation of Bismuth Oxybromide/Titanium Carbide/Hydrophobic Coating

Immerse the cotton fabric coated with bismuth oxybromide/titanium carbide in hydrophobic hexadecyltrimethoxysilane, soak it for 2 hours, take it out, wash and dry to obtain bismuth oxybromide/titanium carbide/hexadecyltrimethoxysilane Silane-coated cotton fabric (Cotton-Ti3C2 _{- BiOBr} -HTEOS).

Embodiment 4

Step 1, pretreatment of cotton cloth:

Arrange 32cm ² cotton in 100mL 0.1mol/L sodium hydroxide solution, soak for 2 hours, and repeatedly wash the soaked cotton cloth in deionized water to remove residual alkali. The above-mentioned fabrics were placed in absolute ethanol, ultrasonically cleaned for 30 min, and dried to obtain experimental cotton cloth (Cotton) for later use.

Step 2, the preparation of titanium carbide:

1 g of titanium aluminum carbide was placed in a mixed solution of 1 g of lithium fluoride and 12 mol/L of 20 mL of hydrochloric acid, and stirred in a water bath at 40 °C for 24 h at a stirring speed of 800 rpm. Wash with deionized water to pH 6, add a small amount of water, sonicate at 800W for 2h, centrifuge at 3500rpm, and take the supernatant to obtain a few-layer or single-layer titanium carbide slurry.

Step 3, Preparation of Titanium Carbide Coating

The experimental cotton was placed in a 3 mol/L titanium carbide slurry, stirred for 1 h, the cotton cloth was taken out, washed with water to remove unbound titanium carbide, and then the cotton cloth was freeze-dried to obtain a titanium carbide-coated cotton fabric (Cotton-Ti _{3 )} . _C2 ).

Step 4, Preparation of Bismuth Oxybromide/Titanium Carbide Coating

The above-mentioned titanium carbide-coated cotton fabric was immersed in 10 mL of ethylene glycol and stirred, 480.07 mg Bi(NO ₃ ) ₃ ·5H ₂ O was added, stirred evenly to disperse it, stirred for 0.5 h, and 10 mL of 0.1 mol/L KBr, and continued stirring for 1 h. The cotton cloth was taken out, washed and dried to obtain a bismuth oxybromide-titanium carbide-coated cotton fabric (Cotton-Ti ₃ C ₂ -BiOBr).

Step 5, Preparation of Bismuth Oxybromide/Titanium Carbide/Hydrophobic Coating

The cotton fabric coated with bismuth oxybromide/titanium carbide was immersed in hydrophobic ethyl orthosilicate, soaked for 2 hours, taken out, washed and dried to obtain bismuth oxybromide/titanium carbide/ethyl orthosilicate coated cotton Fabric (Cotton-Ti3C2 _{- BiOBr} -TEOS).

Analysis of the detection results of embodiment 1,2:

The pure bismuth oxybromide coating was prepared by the following method and served as the control group.

To prepare the bismuth oxybromide coating:

Immerse the pretreated cotton fabric or polyester in 10 mL of ethylene glycol and stir, add 480.07 mg Bi(NO ₃ ) ₃ ·5H ₂ O, stir evenly to disperse it, stir for 0.5 h, and dropwise add 10 mL of 0.1 mol/L KBr, and continued stirring for 1 h. The cotton cloth or polyester is taken out, washed and dried to obtain a cotton fabric (Cotton-BrOBi, PET-BrOBi) coated with bismuth oxybromide-titanium carbide.

Figure 1 shows the low and high magnification scanning electron microscope images of the material after the cotton fabric is self-assembled layer by layer. It can be seen from Figures a and b that the cotton fabric is composed of smooth fibers. From the low magnification images of the loaded coating (c, e, g, i), the preparation of the coating did not affect the macroscopic morphology of the fiber, indicating that the loading of the coating hardly affects the air permeability of the fiber. It can be seen from the inset in Figure 1c that Ti ₃ C ₂ is in a sheet structure, indicating that the surface of the fiber soaked with Ti ₃ C ₂ has a sheet structure attached, and the Ti ₃ C ₂ sheet structure is tightly adsorbed on the fibers of the cotton fabric (Figures 1c and 1d). From the inset in Figure f, it can be seen that the BiOBr synthesized at room temperature has a nanosheet array structure, and the BiOBr nanosheet array is attached to the surface of the cotton fabric fiber. As can be seen in Figures _g and h, the cotton fibers loaded with _Ti3C2 sheets are in nanosheet arrays. This is because the surface of the Ti ₃ C ₂ lamella structure is negatively charged, which can tightly adsorb bismuth ions. The introduction of bromide ions makes the nanosheet array grow in situ on the surface of the material lamella structure, covering the original Ti ₃ C ₂ lamellae. layer structure. The introduction of the hydrophobic coating did not affect the morphology change of the material (Fig. i and Fig. j).

Figure 2 shows the low and high magnification scanning electron microscope images of the polyester material after layer-by-layer self-assembly. It can be seen from the figure that the surface morphology of the material is consistent with the corresponding morphology on the cotton fabric, indicating that different fabrics will not affect the shape of the material.

Figure 3 shows the scanned element surface distribution of different coatings on the surface of cotton fabrics. It can be seen from the figure that Cotton alone has only C and O elements, and Cotton-Ti ₃ C ₂ contains Ti, C and O elements. Cotton-BiOBr contains C, Bi, Br and O elements. Only Cotton-Ti ₃ C ₂ -BiOBr contains Ti, C, Bi, Br and O and is evenly distributed on the surface of the cotton fabric fiber, indicating that Ti ₃ C ₂ and BiOBr are indeed loaded on the surface of the fiber. The method enables the material to be tightly connected to the surface of the fiber without affecting the overall morphology of the fiber.

Figure 4 presents the areal profiles of different coatings on polyester surfaces, which show similar results to cotton fabrics.

晶面与BiOBr的(110)晶面紧密结合在一起，说明了Ti₃C₂与BiOBr异质界面的存在。Figure 5 shows the transmission electron microscope image of Ti3C2 _{- BiOBr on} the surface of the fiber coating, from which it can be seen that the _Ti3C2

The crystal plane is closely combined with the (110) crystal plane of BiOBr, indicating the existence of the heterointerface between Ti ₃ C ₂ and BiOBr.

6 shows the contact angles of Cotton, Cotton-Ti ₃ C ₂ , Cotton-BiOBr, Cotton-Ti ₃ C ₂ -BiOBr, and Cotton-Ti ₃ C ₂ -BiOBr-PDMS in Example 1. FIG. The hydrophobicity of cotton and different coated cottons is judged by the measurement of contact angle. The higher the hydrophobicity, the stronger the ability of the fabric to resist bacterial adhesion. It can be seen from the figure that the polydimethylsiloxane significantly increases the contact angle of the fibers and improves the hydrophobic properties of the fibers.

7 is a contact angle diagram of PET, PET-Ti ₃ C ₂ , PET-BiOBr, PET-Ti ₃ C ₂ -BiOBr, and PET-Ti ₃ C ₂ -BiOBr-PDMS in Example 2. FIG. After modification with polydimethylsiloxane, the surface contact angle increased significantly, which improved the hydrophobicity of the material.

FIG. 8 shows the photothermal curves of each cotton fiber and the modified fiber in Example 1 under simulated sunlight. A certain photothermal effect fiber can damage bacterial proteins and metabolic enzymes adhering to the surface of the fiber, affecting the activity of bacteria. Therefore, the photothermal effect of different coatings under simulated sunlight was tested. Therefore, the different materials were placed in water for 15 minutes, the materials were taken out, and they were placed under simulated sunlight for 15 minutes. The temperature change of the material is recorded. It can be seen from the figure that the temperature of Cotton-Ti ₃ C ₂ , Cotton-Ti ₃ C ₂ -BiOBr and Cotton-Ti ₃ C ₂ -BiOBr-PDMS increased rapidly under light, and the temperature increased to 55°C after 5 min. , indicating that Ti ₃ C ₂ can improve the light absorption capacity of the fiber and promote the photothermal conversion rate, so that Cotton-Ti ₃ C ₂ , Cotton-Ti ₃ C ₂ -BiOBr and Cotton-Ti ₃ C ₂ -BiOBr-PDMS have excellent performance photothermal effect. Cotton-BiOBr has basically no obvious temperature change. This is because _Ti3C2 has strong light absorption under light, which can convert light into heat energy, but _BiOBr has low absorption under light, low photothermal conversion efficiency, and cannot generate heat quickly. Therefore, Cotton-Ti ₃ C ₂ , Cotton-Ti ₃ C ₂ -BiOBr and Cotton-Ti ₃ C ₂ -BiOBr-PDMS can produce excellent photothermal effect under light, and the thermal effect will aggravate the protein damage of bacteria and affect the bacterial active.

Figure 9 shows the photothermal curves of each polyester fiber and modified fiber in Example 2 under simulated sunlight. It can also be seen that PET-Ti ₃ C ₂ , PET-Ti ₃ C ₂ -BiOBr and PET-Ti ₃ C ₂ -BiOBr-PDMS show excellent photothermal effects, and the results show similar photothermal effects to cotton fibers This photothermal effect also affects the protein activity of bacteria and reduces the survival rate of bacteria.

Figure 10 shows the results of bacterial plate coating of Cotton, Cotton- _Ti3C2 , Cotton- _BiOBr , Cotton-Ti3C2 _{- BiOBr} and Cotton-Ti3C2 _{- BiOBr} -PDMS under dark and light conditions. 500 microliters of Staphylococcus aureus bacterial solution with a concentration of 10 ⁷ CFU/mL was placed in a 1 mL centrifuge tube, and the samples were soaked in it respectively. After 15 minutes, the cotton fibers were taken out and divided into dark group and light group. The fibers in the light group were directly irradiated under simulated sunlight for 10 min, and then the fibers were placed in 200 microliters of liquid medium, and all bacteria on the fibers were shaken by ultrasonic waves, and a certain amount was diluted and spread on a solid agar plate at 37°C. Counting was performed after 20 hours of incubation. The fibers in the dark group were directly placed in 200 microliters of liquid medium, and all bacteria on the fibers were shaken by ultrasonic waves. A certain amount of bacteria was diluted and spread on a solid agar plate. After culturing at 37°C for 20 hours, it was counted. It can be seen from the figure that Cotton-BiOBr basically did not exhibit antibacterial properties under light conditions. Cotton-Ti ₃ C ₂ exhibited certain antibacterial properties, and the antibacterial rate of Cotton-Ti ₃ C ₂ -BiOBr was 93.2%, indicating that the Ti ₃ C ₂ -BiOBr coating had excellent antibacterial properties. This is because the coating not only improves the thermal effect of the fiber under light, which reduces the activity of bacteria, in addition, BiOBr acts as a semiconductor, which can generate photo-generated electrons and holes under simulated sunlight, wherein the photo-generated electrons can be absorbed by excellent electrical conductivity. The trapping of Ti ₃ C ₂ reduces the recombination efficiency of photogenerated electrons and holes and increases the production of free radicals. These free radicals cause the bacteria to produce a peroxidative reaction that accelerates bacterial death. Under the synergistic effect of photothermal effect and free radicals, titanium carbide-bismuth oxybromide has excellent antibacterial effect. The introduction of PDMS enables the antibacterial rate of the coating to reach 99.86%, which greatly improves the antibacterial effect of the material. Under dark conditions, the fibers of Cotton-Ti ₃ C ₂ , Cotton-BiOBr and Cotton-Ti ₃ C ₂ -BiOBr did not show bacteriostatic effect, and Cotton-Ti ₃ C ₂ -BiOBr-PDMS inhibited bacterial adhesion rate. 48.37%, indicating that the hydrophobic coating can effectively inhibit the adhesion of bacteria. It shows that the introduction of the hydrophobic coating reduces the adhesion of bacteria to a certain extent, and the synergistic effect of photothermal and free radicals of the titanium carbide-bismuth oxybromide coating improves the antibacterial rate of the fiber.

11 is an antibacterial image of PET, PET-Ti ₃ C ₂ , PET-BiOBr, PET-Ti ₃ C ₂ -BiOBr and PET-Ti ₃ C ₂ -BiOBr-PDMS in the dark and under simulated sunlight. The antibacterial properties of the material were tested in the same way as cotton fibers. As can be seen from the figure, the materials exhibited similar antibacterial properties. The antibacterial rate of Ti3C2 _{- BiOBr} coating was 90.24%, indicating that the coating had obvious antibacterial effect, while the antibacterial rate of PET-Ti3C2 _{- BiOBr} -PDMS was 98.92% under light conditions and 98.92% under dark conditions. The antibacterial rate under 42.94% indicates that the Ti ₃ C ₂ -BiOBr-PDMS coating has excellent bactericidal and antibacterial properties.

PET-Ti3C2 _- BiOBr, Cotton- _{Ti3C2 - BiOBr} , Cotton-Ti3C2 _{- BiOBr} -PDMS and PET-Ti3C2 _{- BiOBr} -PDMS from Figures 8, 9, 10 and 11 above According to the photothermal and antibacterial data, the titanium carbide-bismuth oxybromide coating has excellent photothermal effect, which can reduce the protein activity in bacteria and accelerate the death of bacteria. In addition, bismuth oxybromide can generate photo-generated electrons and holes under light, and titanium carbide, as a photo-generated electron capture agent, can accelerate the separation efficiency of photo-generated electron holes, thereby generating a large number of free radicals, which will cause bacteria to produce Peroxidation, which accelerates bacterial death. The photothermal and free radical synergistic effect of titanium carbide-bismuth oxybromide coating makes it have excellent antibacterial effect. The introduction of the hydrophobic layer makes the number of bacteria adhering to the surface of the fiber less, and under the effect of the same titanium carbide-bismuth oxybromide coating, the antibacterial rate of the fiber is improved.

Bismuth oxyhalide BiOX (X=Cl, Br, I) has an irregular crystal structure and indirect electronic transitions. The nature of the indirect transition means that the excited state electrons need to travel the spatial distance to be emitted to the valence band, which reduces the recombination efficiency of photogenerated electron holes. Bismuth oxyhalide has the same property, and as the atomic number increases, the forbidden band width of the semiconductor gradually decreases, which increases its photocatalytic activity under light. Bismuth oxychloride also showed excellent photocatalytic effect. Therefore, the bismuth oxybromide in the embodiment can be extended to bismuth oxychloride and bismuth oxyiodide. Under sunlight, bismuth oxychloride and bismuth oxyiodide can also be excited to generate photo-generated electrons. Titanium carbide with excellent conductivity can quickly capture photo-generated electrons, prompting a large number of photo-generated electrons to generate free radicals, causing damage to bacteria.

In addition, titanium carbide, one of transition metal carbides, has characteristics similar to those of transition metal carbides. As a new type of two-dimensional material, transition metal carbides (niobium carbide, vanadium carbide, molybdenum carbide, tantalum carbide) have complete metal atomic layers and abundant surface functional groups, and also combine the metal conductivity of transition metal carbides and their Hydrophilicity of the surface of hydroxyl/oxygen/fluorine end groups. Therefore, transition metal carbides can act as electron capture traps, rapidly transfer photogenerated electrons in semiconductors, inhibit the recombination of photogenerated electrons and holes, and improve the utilization rate of electrons. Therefore, the titanium carbide in the examples can be replaced by other transition metal carbides (niobium carbide, vanadium carbide, molybdenum carbide, tantalum carbide).

Furthermore, relational terms such as "first" and "second" etc. are only used to distinguish one element from another having the same name and do not necessarily require or imply any such actual existence between those elements relationship or order.

The present invention has been exemplarily described above. It should be noted that, without departing from the core of the present invention, any simple deformations, modifications or other equivalent replacements that those skilled in the art can do without creative effort fall into the scope of the present invention. The scope of protection of the invention.

Claims (10)

1. an antibacterial fiber, is characterized in that, comprises fabric fiber and the antibacterial coating that is wrapped on the outer surface of described fabric fiber, and described antibacterial coating comprises transition metal carbide and bismuth oxyhalide; Described transition metal carbide It is a layered nanostructure or a sheet nanostructure, and the bismuth oxyhalide is distributed on the surface of the transition metal carbide in the form of a nanosheet array; the bismuth ion in the bismuth oxyhalide and the transition metal carbide pass through electrostatic force. Adsorption and bonding, a heterogeneous interface is formed between the bismuth oxyhalide and the transition metal carbide; the loading amount of the transition metal carbide nanosheet on the fiber is 0.5-1.5 mg/cm ² , and the bismuth oxyhalide is in the fiber. The loading amount on it is 0.5 to 1.5 mg/cm ² . The material of the fabric fiber is one or more of cotton, polyester, nylon, spandex, acrylic or silk; The transition metal carbide is one or more of titanium carbide, niobium carbide, vanadium carbide, tantalum carbide or molybdenum carbide; The bismuth oxyhalide is one or more of bismuth oxychloride, bismuth oxybromide or bismuth oxyiodide. 2. an antibacterial fiber, it is characterized in that, comprise fabric fiber, the antibacterial coating that is wrapped on the outer surface of described fabric fiber and the hydrophobic layer that wraps on the outside of antibacterial coating, and described antibacterial coating comprises transition metal carbide and bismuth oxyhalide; the transition metal carbide is a layered nanostructure or a sheet nanostructure, and the bismuth oxyhalide is distributed on the surface of the transition metal carbide in the form of a nanosheet array; the bismuth ions in the bismuth oxyhalide and The transition metal carbides are combined by electrostatic force adsorption, and a heterogeneous interface is formed between the bismuth oxyhalide and the transition metal carbide; the loading amount of the transition metal carbide nanosheets on the fiber is 0.5-1.5 mg /cm ² , the loading amount of the bismuth oxyhalide on the fiber is 0.5-1.5 mg/cm ² ; The material of the fabric fiber is one or more of cotton, polyester, nylon, spandex, acrylic or silk; The transition metal carbide is one or more of titanium carbide, niobium carbide, vanadium carbide, tantalum carbide or molybdenum carbide; The bismuth oxyhalide is one or more of bismuth oxyfluoride, bismuth oxychloride, bismuth oxybromide or bismuth oxyiodide; The hydrophobic layer is composed of one or more of polydimethylsiloxane, hexadecyltrimethoxysilane or ethyl orthosilicate, and has a thickness of 10-80 nm. 3 . The antibacterial fiber according to claim 1 or 2 , wherein when the transition metal carbide is a layered nanostructure, the number of layers is 1 to 5 layers. 4 . The antibacterial fiber according to claim 1 or 2, wherein the size of the transition metal carbide is 1-5 μm; the size of the bismuth oxyhalide is 300-800 nm. 5. a preparation method of antibacterial fiber, is characterized in that, comprises the following steps: Step 1, fabric fiber pretreatment: The fabric fibers are placed in an alkaline solution with a pH of 11-13, soaked for more than 2 hours, the soaked fabric fibers are washed to remove residual alkali, and the pretreated fabric fibers are obtained after drying; The material of the fabric fiber is one or more of cotton, polyester, nylon, spandex, acrylic or silk; Step 2, preparation of transition metal carbide: The transition metal aluminum carbide is placed in a hydrofluoric acid solution, stirred at 30-40° C., and the soaked transition metal aluminum carbide is washed and dried to obtain the transition metal carbide; The concentration of the hydrofluoric acid solution is 20-40 wt %, and the lithium ion content is 30-50 mg/mL; The transition metal is one or more of titanium, niobium, vanadium, tantalum or molybdenum; The transition metal carbide is a layered nanostructure or a flake nanostructure, and when the transition metal carbide is a layered nanostructure, the number of layers is 1-5; Step 3, preparation of transition metal carbide coating: The transition metal carbide prepared in the second step and the pretreated fabric fibers obtained in the first step are placed in water, and a first slurry is obtained by stirring; the fabric fibers are taken out from the first slurry, washed and dried. A fabric fiber with a transition metal carbide coating is obtained; The mass ratio of the transition metal carbide to the pretreated fabric fiber is 1:20-50; the content of the transition metal carbide in the first slurry is 1-3 mg/L; Step 4, prepare bismuth oxyhalide-transition metal carbide coating: The fabric fibers with the transition metal carbide coating prepared in step 3 and the Bi precursor are added to ethylene glycol, and a second slurry is obtained by stirring; the Bi precursor is a ethylene glycol-soluble containing The salt of Bi ³⁺ ; the mass ratio of the fabric fiber with the transition metal carbide coating and the Bi precursor is 1:4-8; the content of the Bi precursor in the second slurry is 20-50 mg/L ; Add halide to the second slurry, and continue to stir for 0.5-1.5h, the mass ratio of adding the halide and Bi precursor is 1:4-6; take out the fabric fibers from the second slurry, After washing and drying, a fabric fiber with a bismuth oxyhalide-transition metal carbide coating is obtained, and the fabric fiber with a bismuth oxyhalide-transition metal carbide coating has an antibacterial effect; The halide is a sodium or potassium salt of a halogen element, preferably KBr, NaBr, KCl, NaCl, KI or NaI. 6. The preparation method of antibacterial fiber according to claim 5, is characterized in that, It also includes step 5, preparation of the hydrophobic coating: Immerse the fabric fiber with the bismuth oxyhalide-transition metal carbide coating prepared in step 4 in a hydrophobic organic solvent for 2 to 5 hours, take it out, wash and dry to obtain a hydrophobic antibacterial fiber; The hydrophobic organic solvent is one or more of polydimethylsiloxane, hexadecyltrimethoxysilane, and ethyl orthosilicate. 7. the preparation method of antibacterial fiber according to claim 5, is characterized in that, Step 1, fabric fiber pretreatment: put the fabric fiber in an alkaline solution with a pH of 11.5-12.7, soak it for more than 2 hours, wash the soaked fabric fiber to remove the residual alkali, and then place it in anhydrous ethanol, ultrasonically. After cleaning for 30 minutes, the pretreated fabric fibers were obtained after drying. 8. the preparation method of antibacterial fiber according to claim 5, is characterized in that, Step 2, preparation of transition metal carbide: The transition metal aluminum carbide is placed in a hydrofluoric acid solution, stirred at 30-40° C., the soaked transition metal aluminum carbide is washed and dried, and the transition metal carbide is prepared by ultrasonication; In the fourth step, the Bi precursor is one or more of Bi(NO ₃ ) ₃ ·5H ₂ O, BiCl ₃ or bismuth acetate. In the above technical solution, the stirring rate of the stirring is 500-5000 rpm. Another object of the present invention is to provide an application of antibacterial fibers. 9. a kind of application of the antibacterial fiber according to claim 1 or 2 in the fabric weaving process. 10. A garment prepared from the antibacterial fiber according to claim 1 or 2.

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