A method for preparing modified triboelectric cellulose nanofiber membranes and its application

Abstract

The application discloses a preparation method and application of a modified triboelectric cellulose nanofiber membrane, comprising the following steps: synthesizing Ti3C2Tx / MoS2 hybrid nanosheets through a hydrothermal reaction, then grafting the nanosheets to a cellulose surface through tetraethyl orthosilicate hydrolysate, and finally electrospinning and heat-treating to synthesize nanofiber membranes. The balance between low pressure drop and high filtration efficiency is realized through mechanical interception and electrostatic induction, and strong and stable filtration performance is exhibited even under high-temperature and high-humidity conditions. A sterilization rate of 99.9% can be realized in 20 min, the device can accurately detect trace NH3 (0.1 ppm), and can quickly respond, and the response rate to 100 ppm NH3 reaches 86% in 2 seconds. Even after 9 cycles of "test-washing", the triboelectric performance, filtration performance, sterilization and ammonia response of the material still maintain excellent stability.

Description

Technical Field

[0001] This invention belongs to the field of efficient utilization of cellulose and nanoenergy technology, specifically involving a method for preparing a modified triboelectric cellulose nanofiber membrane and its application. Background Technology

[0002] With social development and the widespread use of electronic products, energy consumption has become an increasingly serious problem. Triboelectric nanogenerators, as revolutionary energy conversion devices, can convert low-frequency mechanical energy, which is widely available in nature, into electrical energy. However, the insufficient development of cellulose-based triboelectric layers for triboelectric nanogenerators has become a bottleneck restricting the development of high-performance cellulose-based triboelectric nanogenerators.

[0003] The spread of particulate matter (PM) from various sources and the prevalence of respiratory diseases, exacerbated by events such as the COVID-19 pandemic, pose significant threats to health. Approximately 90% of inhalable particulate matter consists of particles with a diameter equal to or less than 1.0 μm (PM1.0), which are known to carry harmful substances directly into the alveoli, causing respiratory problems and allergies.

[0004] Small-pore-size high-efficiency filters are crucial for preventing the escape of submicron particles, but they typically increase airflow resistance, leading to higher energy costs. Furthermore, in challenging environments such as high temperature, high humidity, and exposure to toxic gases, there is a growing need for self-powered healthcare devices that can both efficiently filter air and monitor health status in real time.

[0005] Triboelectric and electrostatic nanogenerators (TENGs) have emerged as a promising energy harvesting technology. TENGs can convert low-frequency mechanical energy into electrical energy and are characterized by portability and environmental friendliness, thus they have been successfully applied in wearable electronic devices. TENGs do not produce ozone, showing potential for air pollution control, especially in filters. Integrating TENGs into filters can generate electrostatic charges through respiration, enhancing the adsorption of fine particles. Summary of the Invention

[0006] The purpose of this section is to outline some aspects of embodiments of the present invention and to briefly describe some preferred embodiments. Simplifications or omissions may be made in this section, as well as in the abstract and title of this application, to avoid obscuring the purpose of these documents; however, such simplifications or omissions should not be construed as limiting the scope of the invention.

[0007] In view of the problems existing in the above and / or prior art, the present invention is proposed.

[0008] Therefore, the purpose of this invention is to overcome the shortcomings of the prior art and provide a method for preparing a modified triboelectric cellulose nanofiber membrane.

[0009] To solve the above-mentioned technical problems, the present invention provides the following technical solution: a method for preparing a modified triboelectric cellulose nanofiber membrane, characterized in that it includes:

[0010] Synthesis of Ti3C2T via hydrothermal reaction x / MoS2 hybrid nanosheets;

[0011] Ti3C2T was prepared by hydrolysis of tetraethyl orthosilicate. x / MoS2 hybrid nanosheets were grafted onto the surface of a cellulose diacetate solution, and then electrospun and heat-treated to synthesize a modified triboelectric cellulose nanofiber membrane.

[0012] As a preferred embodiment of the preparation method described in this invention, wherein: the Ti3C2T x The preparation method of / MoS2 hybrid nanosheets includes etching Ti3C2T x Ammonium molybdate tetrahydrate, thiourea, and glucose are mixed together; the mixture is added to 5–20 mL of water and reacted at 160–220 °C for 6–20 h.

[0013] As a preferred embodiment of the preparation method described in this invention, wherein: the Ti3C2T x The concentration is 10-50 mg, and AMT accounts for a significant portion of Ti3C2T. x The weight ratio is 10%–300%, the weight ratio of thiourea to AMT is 1000%–1500%, and the glucose is 25–100 mg.

[0014] As a preferred embodiment of the preparation method of the present invention, the method for preparing the cellulose diacetate solution includes dissolving CDA in a mixture of N,N-dimethylacetamide and acetone by weight; wherein the mass of CDA is 0.6-2g; and the weight ratio of N,N-dimethylacetamide to acetone is 0.5-3:1.

[0015] As a preferred embodiment of the preparation method described in this invention, the grafting of Ti3C2Tx / MoS2 hybrid nanosheets onto the surface of a cellulose diacetate solution involves adding the hybrid nanosheets to a cellulose diacetate solution and stirring at 20–40°C for 10–24 h; wherein the cellulose diacetate solution is 8–15 mL.

[0016] As a preferred embodiment of the preparation method of the present invention, the method for preparing the tetraethyl orthosilicate hydrolysate includes mixing TEOS, DMF, water and HCl in a weight ratio of 1:3.5:1 to 5:0.01, and then stirring at 70°C for 0.1 to 2 hours.

[0017] As a preferred embodiment of the preparation method described in this invention, wherein: the Ti3C2T is prepared by hydrolyzing tetraethyl orthosilicate... x / MoS2 hybrid nanosheets were grafted onto the surface of a cellulose diacetate solution by mixing tetraethyl orthosilicate hydrolysate with a cellulose diacetate solution containing hybrid nanosheets at a weight ratio of 1:4 to 7 and stirring at 30 to 80°C for 0.1 to 2 hours.

[0018] As a preferred embodiment of the preparation method described in this invention, the electrospinning conditions are: using a 20-22G needle, operating at a high voltage of 16-24kV, and a spinning distance of 9-12cm.

[0019] As a preferred embodiment of the preparation method described in this invention, the heat treatment is performed under the following conditions: the nanofiber membrane is placed in a tube furnace and heated at 150–200°C for 0.5–4 h in a nitrogen or argon atmosphere, and then heated at 220–260°C for 0.5–4 h.

[0020] Another objective of this invention is to overcome the shortcomings of the prior art and provide a method for preparing a modified triboelectric cellulose nanofiber membrane, and to apply the triboelectric cellulose nanofiber membrane obtained by this method to the positive electrode triboelectric material of a triboelectric nanogenerator.

[0021] Beneficial effects of this invention:

[0022] (1) This invention endows cellulose nanofiber membranes with a strong electron-loss capability, making them a viable alternative to animal hair, polyimide, and nylon as highly triboelectric positive electrode materials. When assembled with a negative electrode material, the voltage reaches as high as 197V. Benefiting from the dual effects of physical interception and electrostatic adsorption, it effectively controls PM2.5. 0.3 PM 0.5 Both PM1 and PM2.5 have filtration efficiencies exceeding 98.5%. After 9 washes, they effectively remove PM2.5. 0.3 The filtration efficiency is still over 90%, and it is willing to test the health status of humans.

[0023] (2) The cellulose nanofiber membrane in this invention can achieve a sterilization rate of 99.9% after 15 minutes under near-infrared light irradiation, and the antibacterial rate is still over 98% after 9 cleanings; it can accurately detect trace amounts of NH3 (0.1ppm) and respond quickly, with a response rate of 86% to 100ppm NH3 within 2 seconds, which can quickly warn of NH3 leakage.

[0024] (3) The process designed in this invention is short, the equipment is simple and the cost is low. It can significantly improve the filtration performance of medical products. It not only provides an effective method for creating wearable self-powered medical and health care devices to cope with challenging environments, but also shows great potential in promoting the development of a new generation of flexible, environmentally friendly and multifunctional electronic products. Attached Figure Description

[0025] To more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort. Wherein:

[0026] Figure 1 Ti3C2T prepared in Example 1 of this invention x Characterization diagram of / MoS2, where, Figure 1 (a) is Ti3C2T x SAED plot of / MoS2 Figure 1 (b) is Ti3C2T x XRD pattern of / MoS2 Figure 1 (c) is Ti3C2T x HRTEM image of / MoS2.

[0027] Figure 2 This is a characterization diagram of cellulose nanofibers from Example 1 of the present invention, wherein... Figure 2 (a) is a SEM image of cellulose nanofibers. Figure 2 (b) is a Raman image of a cellulose nanofiber membrane. Figure 2 (c) is the XRD image of cellulose nanofibers. Detailed Implementation

[0028] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the specific embodiments of the present invention will be described in detail below with reference to the examples in the specification.

[0029] Many specific details are set forth in the following description in order to provide a full understanding of the invention. However, the invention may also be practiced in other ways different from those described herein, and those skilled in the art can make similar extensions without departing from the spirit of the invention. Therefore, the invention is not limited to the specific embodiments disclosed below.

[0030] Secondly, the term "one embodiment" or "embodiment" as used herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of the present invention. The phrase "in one embodiment" appearing in different places in this specification does not necessarily refer to the same embodiment, nor is it a single or selective embodiment that is mutually exclusive with other embodiments.

[0031] Unless otherwise specified, all raw materials used in the embodiments of this invention are commercially available. See Table 1 for details.

[0032] Table 1

[0033]

[0034] Example 1

[0035] (1) Preparation of cellulose nanofiber membranes

[0036] 2.0 g of LiF was dissolved in 40 mL (9 M) hydrochloric acid. Then, 2.0 g of Ti3AlC2 was added to the mixture, and the reaction was carried out at 35 °C for 24 h. Afterwards, the mixture was washed with deionized water until the pH of the supernatant was >6. Then, anhydrous ethanol was added to the precipitate, and the mixture was sonicated for 1 h to react the Ti3C2 with the precipitate. x The thin films were layered. Finally, a stable, dark green monolayer of Ti3C2T was obtained. x Thin slices.

[0037] Select a well-etched single-layer Ti3C2T x It is blended with ammonium molybdate tetrahydrate (AMT), thiourea, and glucose. Among them, Ti3C2T... x The mixture contains 10 mg of AMT, with AMT accounting for 150% of the weight of Ti3C2Tx, thiourea to AMT ratio of 1200%, and 40 mg of glucose. The mixture is added to 8 mL of ultrapure water or deionized water and reacted in a reactor at 190 °C for 10 h to obtain nano-hybrid sheets.

[0038] 1 g of CDA was dissolved in a mixture of N,N-dimethylacetamide and acetone in a weight ratio of 0.5:1, and the mixed solution was 10 mL. The nano-hybrid sheet prepared above was added to the solution and stirred at 20 °C for 15 h.

[0039] TEOS, DMF, water and HCl were mixed in a weight ratio of 1:3.5:2:0.01 and then stirred at 70°C for 0.2 h. The TEOS hydrolysate was mixed with a CDA mixture containing dispersed nano-hybrid sheets in a weight ratio of 1:5 and stirred at 40°C for 0.2 h.

[0040] A 21G needle was selected, and a spinning distance of 11cm was used at 16kV high voltage to obtain a nanofiber membrane. The membrane was then placed in a tube furnace and heated at 180°C for 2 hours in a nitrogen atmosphere, followed by heating at 240°C for 2 hours.

[0041] (2) Fabrication of triboelectric nanogenerators

[0042] The cellulose nanofiber membrane prepared above was selected as the positive electrode of the triboelectric nanogenerator, and the polyvinylidene fluoride and barium titanate nanofiber membrane as the negative electrode with a size of 9 cm⁻¹ was selected as the negative electrode. 2Copper foil was applied to the back of two triboelectric materials, which were then fixed to acrylic plates. Wires were connected to the upper and lower electrodes. A contact-separation power generation test was conducted on the triboelectric nanogenerator at a pressure of 10 N and a frequency of 3 Hz.

[0043] (3) The open-circuit voltage of the modified cellulose-based nanofiber membrane used as a triboelectric nanogenerator in this embodiment is 190V. This demonstrates that the electrical output performance of the triboelectric nanogenerator in this embodiment is significantly improved. (Regarding PM...) 0.3 PM 0.5 The filtration efficiencies for PM1 and PM2.5 are both over 98.58%, 99.02%, and 99.32%, respectively. Even under harsh conditions of high temperature and high humidity (100℃ or 99% RH), the filtration efficiency remains above 90%. After eight cycles of "test-wash," the filtration efficiency for PM2.5 is significantly improved. 0.3 The filtration efficiency remains above 94%. After 15 minutes of near-infrared light irradiation, the antibacterial rate against Escherichia coli and Staphylococcus aureus reaches 99.6%. The device can accurately detect trace amounts of NH3 (0.2 ppm) and responds rapidly, achieving an 82% response rate to 100 ppm NH3 within 2 seconds. Even after 8 cycles of "test-wash," its bactericidal properties and ammonia responsiveness remain extremely stable. By monitoring the wearer's breathing status in real time, respiratory health can be continuously assessed.

[0044] Comparative Example 1

[0045] (1) Preparation of cellulose nanofiber membranes

[0046] 1 g of CDA was dissolved in a mixture of N,N-dimethylacetamide and acetone at a weight ratio of 0.5:1, and the mixture was stirred at 20°C for 15 h. A 21G needle was used to spin nanofiber membranes at a high voltage of 16 kV and a spinning distance of 11 cm. The membranes were then placed in a tube furnace and heated at 180°C for 2 h in a nitrogen atmosphere, followed by heating at 240°C for 2 h.

[0047] (2) Fabrication of triboelectric nanogenerators

[0048] The cellulose nanofiber membrane prepared above was selected as the positive electrode of the triboelectric nanogenerator, and the polyvinylidene fluoride and barium titanate nanofiber membrane as the negative electrode with a size of 9 cm⁻¹ was selected as the negative electrode. 2 Copper foil was applied to the back of two triboelectric materials, which were then fixed to acrylic plates. Wires were connected to the upper and lower electrodes. A contact-separation power generation test was conducted on the triboelectric nanogenerator at a pressure of 10 N and a frequency of 3 Hz. The obtained open-circuit voltage was 65 V.

[0049] Example 2

[0050] (1) Preparation of cellulose nanofiber membranes

[0051] 2.0 g of LiF was dissolved in 40 mL (9 M) hydrochloric acid. Then, 2.0 g of Ti3AlC2 was added to the mixture, and the reaction was carried out at 35 °C for 24 h. Afterwards, the mixture was washed several times with deionized water until the pH of the supernatant was >6. Then, anhydrous ethanol was added to the precipitate, and the mixture was sonicated for 1 h to react the Ti3C2 with the precipitate. x The thin films were layered. Finally, a stable, dark green monolayer of Ti3C2T was obtained. x Thin slices.

[0052] Select a well-etched single-layer Ti3C2T x It is blended with AMT, thiourea, and glucose. The Ti3C2Tx content is 12 mg, and AMT accounts for 12 mg of Ti3C2Tx. x The weight ratio of thiourea to AMT is 230%, the ratio is 1300%, and 40 mg of glucose is selected. The above blend is added to 10 mL of ultrapure water or deionized water and reacted in a reactor at 200 °C for 12 h to obtain hybrid nanosheets.

[0053] 1.5 g of CDA was dissolved in a mixture of N,N-dimethylacetamide and acetone in a weight ratio of 0.3:1, and the mixed solution was 12 mL. The nano-hybrid sheet prepared above was added to the solution and stirred at 30 °C for 20 h.

[0054] TEOS, DMF, water and HCl were mixed in a weight ratio of 1:3.5:1.5:0.01 and then stirred at 70°C for 0.4 h. The TEOS hydrolysate was mixed with a CDA mixture containing dispersed nano-hybrid sheets in a weight ratio of 1:6 and stirred at 40°C for 0.1 h.

[0055] A 21G needle was selected, and a spinning distance of 10cm was used at 18kV high voltage to obtain a nanofiber membrane. The membrane was then placed in a tube furnace and heated at 200°C for 1 hour in a nitrogen atmosphere, followed by heating at 250°C for 3 hours.

[0056] (2) Fabrication of triboelectric nanogenerators

[0057] The modified cellulose fiber membrane prepared above was selected as the positive electrode of the triboelectric nanogenerator, and the polyvinylidene fluoride and barium titanate nanofiber membrane as the negative electrode with a size of 9 cm⁻¹ was selected as the negative electrode. 2 Copper foil was applied to the back of two triboelectric materials, which were then fixed to acrylic plates. Wires were connected to the upper and lower electrodes. A contact-separation power generation test was conducted on the triboelectric nanogenerator at a pressure of 10 N and a frequency of 3 Hz.

[0058] (3) The open-circuit voltage of the modified cellulose-based nanofiber membrane used as a triboelectric nanogenerator in this embodiment is 180V. This demonstrates that the electrical output performance of the triboelectric nanogenerator in this embodiment is significantly improved. (Regarding PM...) 0.3 PM 0.5 The filtration efficiencies for PM0.3 and PM1 are both over 96.72%, 98.12%, and 99.02%, respectively. Even under harsh conditions of high temperature and high humidity (100℃ or 99% RH), the filtration efficiency remains above 88%. After six cycles of "test-wash," the filtration performance for PM0.3 still exceeds 91%. After 15 minutes of near-infrared light irradiation, the antibacterial rate against Escherichia coli and Staphylococcus aureus reaches 99.1%. The device can accurately detect trace amounts of NH3 (0.2 ppm) and responds quickly, achieving a response rate of 81.3% for 100 ppm NH3 within 5 seconds. Even after eight cycles of "test-wash," the bactericidal properties and ammonia responsiveness remain extremely stable. By monitoring the wearer's breathing status in real time, respiratory health can be continuously assessed.

[0059] Comparative Example 2

[0060] (1) Preparation of cellulose nanofiber membranes

[0061] 1.5 g of CDA was dissolved in a mixture of N,N-dimethylacetamide and acetone at a weight ratio of 0.3:1, and the mixture was stirred at 30°C for 20 h. A 21 G needle was used to spin nanofiber membranes at 18 kV high voltage with a spinning distance of 10 cm. The membranes were then placed in a tube furnace and heated at 200°C for 1 h in a nitrogen atmosphere, followed by heating at 250°C for 3 h.

[0062] (2) Fabrication of triboelectric nanogenerators

[0063] The cellulose nanofiber membrane prepared above was selected as the positive electrode of the triboelectric nanogenerator, and the polyvinylidene fluoride and barium titanate nanofiber membrane as the negative electrode with a size of 9 cm⁻¹ was selected as the negative electrode. 2 Copper foil was applied to the back of two triboelectric materials, which were then fixed to acrylic plates. Wires were connected to the upper and lower electrodes. A contact-separation power generation test was conducted on the triboelectric nanogenerator at a pressure of 10 N and a frequency of 3 Hz. The obtained open-circuit voltage was 61 V.

[0064] Example 3

[0065] (1) Preparation of cellulose nanofiber membranes

[0066] 2.0 g of LiF was dissolved in 40 mL (9 M) hydrochloric acid. Then, 2.0 g of Ti3AlC2 was added to the mixture, and the reaction was carried out at 35 °C for 24 h. Afterwards, the mixture was washed several times with deionized water until the pH of the supernatant was >6. Then, anhydrous ethanol was added to the precipitate, and the mixture was sonicated for 1 h to react the Ti3C2 with the precipitate. x The thin films were layered. Finally, a stable, dark green monolayer of Ti3C2T was obtained. x Thin slices.

[0067] Select a well-etched single-layer Ti3C2T x It is blended with AMT, thiourea, and glucose. Among them, Ti3C2T... x The concentration of AMT in Ti3C2T is 15mg. x The weight ratio of thiourea to AMT is 1500%, and 70 mg of glucose is selected. The above blend is added to 10 mL of ultrapure water or deionized water and reacted in a reactor at 220 °C for 12 h. 1.4 g of CDA is dissolved in a mixture of N,N-dimethylacetamide and acetone at a weight ratio of 0.25:1, and the mixed solution is 10 mL. The nano-hybrid sheet prepared above is added to the solution and stirred at 35 °C for 24 h.

[0068] TEOS, DMF, water and HCl were mixed in a weight ratio of 1:3.5:2.3:0.01 and then stirred at 60°C for 1.1 h. The TEOS hydrolysate was mixed with a CDA mixture containing dispersed nano-hybrid sheets in a weight ratio of 1:4.5 and stirred at 0.5°C for 0.5 h.

[0069] A 21G needle was selected, and a spinning distance of 11cm was used at 20kV high voltage to obtain a nanofiber membrane. The membrane was then placed in a tube furnace and heated at 180°C for 2 hours in a nitrogen atmosphere, followed by heating at 250°C for 3 hours.

[0070] (2) Fabrication of triboelectric nanogenerators

[0071] The modified cellulose aerogel prepared above was selected as the positive electrode of the triboelectric nanogenerator, and the polyvinylidene fluoride and barium titanate nanofiber membrane as the negative electrode with a size of 9 cm⁻¹ was selected as the negative electrode. 2 Copper foil was applied to the back of two triboelectric materials, which were then fixed to acrylic plates. Wires were connected to the upper and lower electrodes. A contact-separation power generation test was conducted on the triboelectric nanogenerator at a pressure of 10 N and a frequency of 3 Hz.

[0072] (3) The open-circuit voltage of the modified cellulose-based nanofiber membrane used as a triboelectric nanogenerator in this embodiment is 185V. This demonstrates that the electrical output performance of the triboelectric nanogenerator in this embodiment is significantly improved. (Regarding PM...) 0.3 PM0.5 The filtration efficiencies for PM0.3 and PM1 are both over 97.82%, 98.82%, and 99.12%, respectively. Even under harsh conditions of high temperature and high humidity (100℃ or 99% RH), the filtration efficiency remains above 90%. After 9 cycles of "test-wash," the filtration performance for PM0.3 still exceeds 94%. After 15 minutes of near-infrared light irradiation, the antibacterial rate against Escherichia coli and Staphylococcus aureus reaches 99.4%. The device can accurately detect trace amounts of NH3 (0.1 ppm) and responds quickly, achieving a response rate of 82.3% for 100 ppm NH3 within 6 seconds. Even after 9 cycles of "test-wash," the bactericidal properties and ammonia responsiveness remain extremely stable. By monitoring the wearer's breathing status in real time, respiratory health can be continuously assessed.

[0073] Comparative Example 3

[0074] (1) Preparation of cellulose nanofiber membranes

[0075] 1.4 g of CDA was dissolved in a mixture of N,N-dimethylacetamide and acetone at a weight ratio of 0.25:1 and stirred at 35°C for 15 h. A 21G needle was used to spin nanofiber membranes at a high voltage of 20 kV with a spinning distance of 11 cm. The membranes were then placed in a tube furnace and heated at 180°C for 2 h in a nitrogen atmosphere, followed by heating at 250°C for 3 h.

[0076] (2) Fabrication of triboelectric nanogenerators

[0077] The cellulose nanofiber membrane prepared above was selected as the positive electrode of the triboelectric nanogenerator, and the polyvinylidene fluoride and barium titanate nanofiber membrane as the negative electrode with a size of 9 cm⁻¹ was selected as the negative electrode. 2 Copper foil was applied to the back of two triboelectric materials, which were then fixed to acrylic plates. Wires were connected to the upper and lower electrodes. A contact-separation power generation test was conducted on the triboelectric nanogenerator at a pressure of 10 N and a frequency of 3 Hz. The obtained open-circuit voltage was 52 V.

[0078] The corresponding selected area electron diffraction (SAED) pattern ( Figure 1 a) shows the diffraction spots and two diffraction rings, attributed to the hexagonal crystal structure of MXene and the (100) and (110) polycrystalline structures of MoS2, respectively. The characteristic peaks corresponding to the (002) plane of MXene indicate that the crystal structure of MXene was retained after the hydrothermal reaction. Figure 1b). Furthermore, the XRD pattern of Ti3C2Tx / MoS2 shows new peaks at (002), (100), (103), (105), (110), and (201), which are attributed to MoS2, indicating the coexistence of Ti3C2Tx and MoS2 crystal phases. High-resolution TEM (HRTEM) images of Ti3C2Tx / MoS2 show that the measured lattice plane spacing of Ti3C2Tx is 0.36 nm, corresponding to the (002) plane. Furthermore, the experimental results indicate that the MoS2 nanosheets are few-layer crystals with a vertical structure. The lattice plane spacings are approximately 0.62 nm and 0.12 nm, corresponding to the (002) and (100) planes of MoS2, respectively. Figure 1 c). These findings confirm that Ti3C2Tx and MoS2 coexist and form heterojunctions.

[0079] SEM images show that CTTM is composed of interwoven nanofibers and mixed nanosheets dispersed within the fibers. Figure 2 a) Raman spectroscopy shows that at 1100 cm⁻¹ -1 The characteristic peaks of stretching vibrations of glycosides in cellulose observed at the site were retained after modification. Figure 2 b). At 208 and 502cm -1 (Bending and torsional vibrations of Si-O-Si), 442 cm -1 (Bending vibrations of O-Si-O) and 778 and 1100 cm -1 The peak at (Si-O tensile vibration) corresponding to silicon dioxide (SiO2) indicates that TEOS has been transformed into SiO2.

[0080] CT, CTT, and CTTM all retain the characteristic crystallization peak of CD at 17.8° (corresponding to the (200) plane). Figure 2 c). Compared to CD, the peak intensity of CT is slightly lower, which may be due to the reduced crystallinity of cellulose caused by the dehydration condensation of silanols and hydroxyl groups on the CD surface. Furthermore, a characteristic 21° SiO2(101) planar peak was observed in CT, CTT, and CTTM. Figure 1 Compared to the b-type, the diffraction peaks induced by Ti3C2Tx and Ti3C2Tx / MoS2 confirmed that the synthesis of CTT and CTTM did not significantly alter the crystal structure of cellulose and CT during the modification process. XRD analysis further confirmed the conclusions of the Raman spectroscopy. These analyses indicate that the cellulose nanofiber membrane was successfully synthesized.

[0081] The nanofiber membrane prepared by electrospinning in this invention has strong application prospects in the field of air filtration. Triboelectric nanogenerators, which form an electrostatic field between two triboelectric materials, can polarize PM in the air and adsorb it onto the surface of the triboelectric materials. Therefore, combining the two can efficiently filter PM in the air. In extreme environments, such as fires, bacterial growth, high temperature and humidity, and toxic gas leaks are often present. Therefore, there is an urgent need for a multifunctional air filtration device. These complex environments place higher demands on the development of novel air filtration devices. MXene and MoS2 possess photothermal properties and ammonia responsiveness, forming tightly bound MXene / MoS2 heterocyclic nanosheets through a hydrothermal reaction. Furthermore, the excellent conductivity of the nanohybrid nanosheets can improve the output performance of the triboelectric nanogenerator. The high-temperature conversion of TEOS to SiO2 not only improves the triboelectric properties but also enhances the material's resistance to high temperature and humidity.

[0082] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention, and all such modifications or substitutions should be covered within the scope of the present invention.

Claims

1. A method for preparing a modified triboelectric cellulose nanofiber membrane, characterized by: The application relates to a preparation method of a triboelectric cellulose nanofiber membrane. Ti3C2T x / MoS2 hybrid nanosheets; Ti3C2T x / MoS2 hybrid nanosheets were grafted onto the surface of cellulose diacetate solution, and finally electrospun and heat treated to synthesize modified triboelectric cellulose nanofiber membranes; The Ti3C2T x The preparation method of the Ti3C2T x , ammonium molybdate tetrahydrate, thiourea, and glucose are blended; the blend is added into 5-20 mL of water and reacted at 160-220°C for 6-20 h. The preparation method of the cellulose diacetate solution comprises the following steps: dissolving cellulose diacetate (CDA) in a mixture of N,N-dimethylacetamide and acetone to obtain the cellulose diacetate solution; wherein the mass of the CDA is 0.6-2 g; the weight ratio of the N,N-dimethylacetamide to the acetone is 0.5-3:

1. The Ti3C2T x Grafting the Ti3C2T / MoS2 hybrid nanosheets to the surface of the cellulose diacetate solution is stirring the hybrid nanosheets in the cellulose diacetate solution at 20-40 DEG C for 10-24 h; wherein the cellulose diacetate solution is 8-15 mL. The preparation method of the tetraethyl orthosilicate hydrolysate comprises the following steps: mixing tetraethyl orthosilicate, DMF, water and HCl according to a weight ratio of 1:3.5:1-5:0.01, and then stirring at 70 DEG C for 0.1-2 h; Ti3C2T x The Ti3C2T / MoS2 hybrid nanosheets are grafted to the surface of the cellulose diacetate solution by mixing the tetraethyl orthosilicate hydrolysate with the cellulose diacetate solution to which the hybrid nanosheets are added in a weight ratio of 1:4~7, and stirring at 30~80℃ for 0.1~2h.

2. The production method according to claim 1, characterized by: The Ti3C2Tx is 10-50 mg, the weight ratio of AMT to Ti3C2Tx is 10%-300%, the weight ratio of thiourea to AMT is 1000%-1500%, and the glucose is 25-100 mg.

3. The production method according to claim 1, wherein: The electrostatic spinning condition is that a 20-22G needle is selected, a high voltage of 16-24 kV is selected, and a spinning distance of 9-12 cm is selected to obtain the nanofiber membrane.

4. The production method according to claim 1, wherein: The heat treatment condition is that the nanofiber membrane is placed in a tube furnace, heated at 150-200 DEG C for 0.5-4 h in a nitrogen or argon atmosphere, and then heated at 220-260 DEG C for 0.5-4 h.

5. Application of the triboelectric cellulose nanofiber membrane prepared by the preparation method of claim 1 to a positive triboelectric material of a triboelectric nanogenerator.

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