Friction power generation external field regulation MXene-PU SERS substrate and preparation method and application thereof
By controlling the external field of triboelectric generation to enhance surface plasmon resonance in the MXene-PU SERS substrate, the problem of insufficient detection sensitivity and stability of the MXene substrate is solved. This achieves SERS detection with high sensitivity, stability and portability, and is suitable for fields such as food safety, medical testing and biosensing.
Patent Information
- Application Number
- CN202511686628.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-11-18
- Publication Date
- 2026-01-16
AI Technical Summary
Existing SERS substrate material MXene has shortcomings in terms of detection sensitivity and stability, and traditional electrochemical power generation enhancement methods are complex and inconvenient to carry, which limits their application in rapid on-site detection.
The MXene-PU SERS substrate is controlled by triboelectric external field, which enhances the local surface plasmon resonance effect by generating a transient high-voltage electric field through triboelectric power generation. This simplifies the detection system and allows for integration with flexible electronic devices, enabling self-powered operation without the need for an external power source.
It improves the sensitivity and stability of detection, enhances biocompatibility, simplifies the operation process, adapts to different environmental conditions, and expands the application prospects of wearable sensors.
Smart Images
Figure CN121347484A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of composite nanomaterials technology, specifically to a triboelectric power generation external field-controlled MXene-PUSERS substrate, its preparation method, and its application. Background Technology
[0002] Raman spectroscopy is an analytical method based on the Raman scattering effect. It analyzes the scattered spectrum with a frequency different from that of the incident light to obtain information about molecular vibrations and rotations, and is applied to molecular structure research. However, conventional Raman spectroscopy is limited by a low scattering cross section (10). -30 cm 2 The limitations of traditional techniques (e.g., molecular structure) have led to low detection sensitivity. The discovery of surface-enhanced Raman scattering (SERS) has overcome these limitations, providing a revolutionary solution for molecular detection. In the few decades since the discovery of SERS, high-performance SERS substrate designs have emerged, including noble metal nanostructures, composite nanostructures, core-shell nanostructures, metal oxides, single-element semiconductors, organic materials, transition metal sulfides, and various nano-metal-based hybrid substrates.
[0003] MXene, a novel two-dimensional transition metal-carbon compound, possesses low visible light absorption, high specific surface area, fluorescence quenching, and excellent molecular enrichment properties, and has been proven to exhibit superior SERS activity. As a SERS substrate material, MXene enhances biocompatibility, making analytes easier to detect by Raman spectroscopy. Furthermore, by quenching fluorescence, it suppresses fluorescence interference in resonance spectroscopy measurements, significantly improving the signal-to-noise ratio of detection.
[0004] While MXene has shown great promise as a substrate material for SERS, its enhancement of SERS is primarily chemical (CM), leading to low sensitivity of MXene SERS substrates. Furthermore, current applications mainly utilize solution or colloidal materials as substrates, which are prone to aggregation, preventing the full utilization of surface active sites. Therefore, developing novel SERS substrate systems that combine high sensitivity, excellent stability, and mechanical adaptability has become a pressing technical challenge in this field.
[0005] Traditional electrochemical power generation to enhance SERS signals has significant limitations: First, electrochemical systems typically require complex electrolyte systems and electrode configurations, resulting in bulky devices and cumbersome operation; second, side reactions that may occur during the electrochemical process can interfere with the chemical environment of the analyte molecules, affecting the stability and reproducibility of the SERS signal; and third, electrochemical methods are difficult to port, limiting their application in rapid on-site detection. Therefore, there is an urgent need to develop a novel SERS substrate system that can be controlled off-site and possesses high sensitivity, excellent stability, and mechanical adaptability. Summary of the Invention
[0006] To address the shortcomings of the aforementioned background technologies, this invention discloses a triboelectric external field-controlled MXene-PU SERS substrate with high stability, clean signal, and high sensitivity, along with its fabrication method and applications. Through triboelectric external field-controlled SERS technology, the transient high-voltage electric field generated effectively enhances the local surface plasmon resonance effect of the substrate. This self-powered system eliminates the need for an external power source, simplifying the detection system. Furthermore, it can be integrated with flexible electronic devices, opening up new avenues for developing wearable SERS sensors. This invention solves the problems of poor flexibility, weak environmental adaptability, poor biocompatibility, high fabrication cost, inconvenience in portability, and complex fabrication processes in existing SERS substrates.
[0007] Specifically, this invention provides a method for preparing a triboelectric power generation external field-controlled MXene-PU SERS substrate, comprising the following steps: Step 1: Preparation of monolayer Ti3C2T x MXene colloidal solution; Step 2: The microstructure of Ti3C2T dome x Preparation of MXene thin films; the single-layer Ti3C2T x After concentration, the MXene colloidal solution was coated onto a hemispherical concave membrane of ethylene-vinyl acetate copolymer. It was then placed in a vacuum oven at 0.001 MPa to 0.01 MPa for 2 to 5 minutes, removed, and dried at room temperature. Subsequently, it was placed at a temperature of 60 to 90°C. o After peeling with anhydrous ethanol for 1-5 minutes, a flexible dome-shaped Ti3C2T microstructure was obtained. x MXene thin films; Step 3: Preparation of dome-shaped microstructure PU film; Aqueous PU solution is dropped into a copper hemispherical concave film, placed in a vacuum oven with a vacuum degree of 0.001 MPa ~ 0.01 MPa for 2 ~ 5 min, then removed, dried at room temperature and peeled off to obtain a flexible dome-shaped microstructure PU film; Step 4: Preparation of the MXene-PU SERS substrate for triboelectric power generation under external field control; the Ti3C2T...x Electrodes are led out from both the MXene film and the PU film, with the PU film vertically covering the Ti3C2T. x A triboelectric nanogenerator was assembled on top of the MXene film; Step 5: Add a controllable clicker to the triboelectric nanogenerator. Adjust the output voltage and current of the triboelectric nanogenerator by controlling the striking frequency of the controllable clicker.
[0008] Preferably, the preparation of monolayer Ti3C2T in step one is... x The process of MXene colloidal solution is as follows: Step S1: Disperse LiF uniformly in hydrochloric acid solution to obtain a mixed solution of hydrochloric acid and LiF; Step S2: Add Ti3AlC2MAX precursor powder to the mixed solution of hydrochloric acid and LiF, stir and etch at 10~50℃ for 20~50 h, and then perform post-treatment to obtain a clay-like precipitate; Step S3: The clay-like precipitate is uniformly dispersed in deionized water, and after sonication and centrifugation, the upper colloidal solution is taken to obtain the monolayer Ti3C2T. x MXene colloidal solution.
[0009] Preferably, the concentration of the hydrochloric acid solution is 8-12 mol / L; the mass of the LiF is 0.5-5 g; the volume of the hydrochloric acid solution is 10-50 mL; the mass ratio of the Ti3AlC2MAX precursor powder to LiF is (0.5-3):(0.8-2.4); the monolayer Ti3C2T x The concentration of MXene colloidal solution is 5 ~ 20 mg / mL.
[0010] Preferably, the volume of the deionized water in step S3 is 10-50 mL; the ultrasonic process is as follows: the solution is broken up for 20-60 min using an ultrasonic cell disruptor under ultrasonic power of 40-100 W, the centrifugation speed is 1000-8000 rpm, and the centrifugation time is 10-50 min.
[0011] Preferably, the monolayer Ti3C2T described in step two x During the concentration of the MXene colloidal solution, the monolayer Ti3C2T x Centrifuging the MXene colloidal solution at 10000–13000 rpm for 50–90 min yielded Ti3C2T. xMXene concentrate; the distribution array of the ethylene-vinyl acetate copolymer hemispherical concave membrane is 30×30 ~ 100×100, the hemispherical diameter is 100~500 μm, and the size is 10 mm×10 mm ~ 50 mm×50 mm; the room temperature drying time is 10 ~ 20 h.
[0012] Preferably, the volume of the aqueous PU solution in step three is 2-5 mL, the solid content is 30-50%, the distribution array of the copper hemispherical concave film is 30×30-100×100, the diameter of the hemisphere is 100-500 μm, the size is 10 mm×10 mm-50 mm×50 mm, and the drying time at room temperature is 10-20 h.
[0013] Preferably, the electrode in step four is a copper wire.
[0014] Preferably, the striking frequency of the controllable clicker in step five is 1~10 Hz.
[0015] A second aspect of the present invention provides a triboelectric power generation external field-controlled MXene-PUSERS substrate prepared by the above preparation method.
[0016] The third aspect of the present invention provides an application of the above-mentioned triboelectric external field-controlled MXene-PU SERS substrate in SERS detection, which achieves the modulation of the intensity of the Rhodamine 6G Raman spectral signal by controlling the pressing frequency of the controllable clicker.
[0017] Compared with existing technologies, the advantages of this substrate are mainly as follows: This invention utilizes an electric field-plasma synergistic mechanism, eliminating the need for an electrochemical electrolysis cell. This simplifies conventional setup requirements and operational complexity, thereby improving the flexibility and environmental adaptability of SERS detection.
[0018] This invention uses MXene as the substrate material, which improves biocompatibility and can suppress fluorescence interference in resonance spectroscopy measurements by quenching fluorescence, thus greatly improving the signal-to-noise ratio of the detection.
[0019] The triboelectric power generation MXene-PU SERS substrate provided by this invention can generate a strong local electric field at the interface through efficient conversion of mechanical energy to electrical energy, thus overcoming the limitation of traditional laser excitation relying on high laser power. Compared with traditional field power generation, it does not require an additional power supply device, promotes the integration of clean energy and sensing technology, and opens up an innovative path for green analytical chemistry.
[0020] The triboelectric external field-controlled MXene-PU SERS substrate of this invention has good flexibility and can accurately detect molecules according to different conditions and complex environments. Therefore, it has a wider range of application prospects in the fields of food safety, medical detection and biosensing. Attached Figure Description
[0021] Figure 1 Multilayer Ti3C2T provided in Example 1 x SEM photos; Figure 2 Macroscopic and microscopic photographs of the dome-shaped MXene thin film provided in Example 1; Figure 3 Macro and micro photographs of the dome-shaped microstructure PU film provided in Example 1; Figure 4 The short-circuit current diagram of the MXene-PU triboelectric nanogenerator with an external vertical impact frequency of 2 Hz provided in Example 1; Figure 5 Open-circuit voltage diagrams of MXene-PU triboelectric nanogenerators with different external vertical impact frequencies provided in Example 1; Figure 6 Surface-enhanced Raman spectra of Rhodamine 6G on MXene-PU SERS substrates with different external vertical impact frequencies provided for Example 2 and Comparative Example 1.
[0022] Figure 7 The surface-enhanced Raman spectra of different concentrations of Rhodamine 6G on the triboelectric field-controlled MXene-PU SERS substrate provided in Example 3. Detailed Implementation
[0023] To enable those skilled in the art to better understand and implement the technical solutions of the present invention, the present invention will be further described below in conjunction with specific embodiments and accompanying drawings. However, the embodiments described are not intended to limit the present invention.
[0024] This invention provides a method for preparing a triboelectric power generation external field-controlled MXene-PU SERS substrate, comprising the following steps: Step 1: Preparation of monolayer Ti3C2T xThe specific process for obtaining the MXene colloidal solution is as follows: Step S1: LiF is uniformly dispersed in hydrochloric acid solution to obtain a mixed solution of hydrochloric acid and LiF; Step S2: Ti3AlC2MAX precursor powder is added to the mixed solution of hydrochloric acid and LiF, and stirred and etched at 10~50℃ for 20~50 h. After post-treatment, a clay-like precipitate is obtained; Step S3: The clay-like precipitate is uniformly dispersed in deionized water, and after sonication and centrifugation, the upper colloidal solution is taken to obtain a monolayer Ti3C2T x MXene colloidal solution; Specifically, the concentration of the hydrochloric acid solution is preferably 8-12 mol / L; the mass of LiF is preferably 0.5-5 g, for example, 0.5 g, 1.6 g, 2.0 g, 2.8 g, 3.5 g, 4.5 g, or 5.0 g; the volume of the hydrochloric acid solution is preferably 10-50 mL, for example, 10 mL, 20 mL, 30 mL, 40 mL, or 50 mL; the mass ratio of Ti3AlC2MAX precursor powder to LiF is preferably (0.5-3):(0.8-2.4), for example, 0.5:0.8, 1.6:1.5, 2.5:2.1, or 3:2.4; monolayer Ti3C2T x The concentration of the MXene colloidal solution is preferably 5 to 20 mg / mL, for example, 5 mg / mL, 10 mg / mL, 15 mg / mL, or 20 mg / mL.
[0025] Specifically, the post-processing in step S2 is as follows: the etched product is centrifuged and washed with a certain amount of 12 M hydrochloric acid at 8000-10000 rpm for 10-20 min, then the supernatant is removed, and the acid washing is repeated three times. Subsequently, the precipitate is centrifuged and washed repeatedly with deionized water for 10-15 min each time at a speed of 8000-10000 rpm until the pH value of the supernatant reaches neutral. Centrifugation is then stopped, the supernatant is discarded, and the lower layer of expanded clay-like precipitate is collected.
[0026] Specifically, in step S3, the clay-like precipitate is dispersed in 10-50 mL of deionized water. The solution is then broken up using an ultrasonic cell disruptor for 20-60 min at an ultrasonic power of 40-100 W. Finally, the solution is centrifuged at 1000-8000 rpm for 10-50 min, and the supernatant after centrifugation is collected; this is the monolayer Ti3C2T. x MXene colloidal solution.
[0027] Step 2: The microstructure of Ti3C2T dome xPreparation of MXene thin films; preparation of monolayer Ti3C2T x After concentration, the MXene colloidal solution is coated onto a hemispherical concave membrane of ethylene-vinyl acetate copolymer. It is then placed in a vacuum oven with a vacuum level preferably between 0.001 MPa and 0.01 MPa (e.g., 0.001 MPa, 0.005 MPa, or 0.01 MPa), and dried for a preferred time of 2 to 5 minutes (e.g., 2 minutes, 3 minutes, 4 minutes, or 5 minutes). The membrane is then dried at room temperature, followed by a temperature preferably between 60 and 90 degrees Celsius. o In anhydrous ethanol of C, for example at a temperature of 60°C o C, 70 o C, 80 o C, 90 o C. The preferred settling time is 1-5 minutes before peeling, for example, 1 minute, 2 minutes, 3 minutes, 4 minutes, or 5 minutes, to obtain a flexible dome-shaped microstructure Ti3C2T. x MXene thin films; Specifically, in step two, a single layer of Ti3C2T x During the concentration of MXene colloidal solution, monolayer Ti3C2T x Centrifuging the MXene colloidal solution at 10000–13000 rpm for 50–90 min yielded Ti3C2T. x MXene concentrate; the preferred distribution array of the ethylene-vinyl acetate copolymer hemispherical concave membrane is 30×30 ~ 100×100, for example, 30×30, 40×40, 50×50, 60×60, 70×70, 80×80, 90×90, 100×100; the preferred hemispherical diameter is 100 ~ 500 μm, for example, 100μm, 200μm, 300μm, 400μm, 500μm; the preferred size is 10 mm×10 mm ~ 50 mm×50 mm, for example, 10 mm×10 mm, 20 mm×20 mm, 30 mm×30 mm, 40 mm×40 mm, 50 mm×50 mm; the preferred drying time at room temperature is 10 ~ 20 h.
[0028] Step 3: Preparation of dome-shaped microstructure PU film; 2-5 mL of aqueous PU solution with a solid content of 30-50% is dropped into a copper hemispherical concave film, and placed in a vacuum oven with a vacuum degree preferably of 0.001 MPa-0.01 MPa, for example, 0.001 MPa, 0.005 MPa, or 0.01 MPa. The drying time is preferably 2-5 min, for example, 2 min, 3 min, 4 min, or 5 min. The film is then dried at room temperature and peeled off to obtain a flexible dome-shaped microstructure PU film. Specifically, the preferred distribution array of the copper hemispherical concave film is 30×30 ~ 100×100, for example, 30×30, 40×40, 50×50, 60×60, 70×70, 80×80, 90×90, 100×100; the preferred hemispherical diameter is 100 ~ 500 μm, for example, 100 μm, 200 μm, 300 μm, 400 μm, 500 μm; and the preferred size is 10 mm×10 mm ~ 50 mm×50 mm, for example, 10 mm×10 mm, 20 mm×20 mm, 30 mm×30 mm, 40 mm×40 mm, 50 mm×50 mm; the drying time at room temperature is 10 ~ 20 h.
[0029] Step 4: Preparation of MXene-PU SERS substrate for triboelectric power generation under external field control; Ti3C2T x Electrodes are drawn out from both the MXene film and the PU film, and the PU film is vertically covered on top of the Ti3C2Tx MXene film to form a triboelectric nanogenerator; Specifically, the electrode in step four is a copper wire.
[0030] Step 5: Add a controllable clicker to the triboelectric nanogenerator. Adjust the output voltage and current of the triboelectric nanogenerator by controlling the striking frequency of the controllable clicker.
[0031] Specifically, the preferred striking frequency of the controllable clicker in step five is 1~10 Hz, for example, it can be 1 Hz, 2 Hz, 5 Hz, 7 Hz, 9 Hz, or 10 Hz.
[0032] The present invention also provides an application of triboelectric external field control of MXene-PU SERS substrate in SERS detection, which achieves the control of the intensity of Rhodamine 6G Raman spectral signal by controlling the pressing frequency of a controllable clicker.
[0033] Specifically, the preferred concentration of the tested Rhodamine 6G solution is... For example, it can be .
[0034] It should be noted that, unless otherwise specified, the experimental methods used in this invention are all conventional methods; and the reagents and materials used, unless otherwise specified, are all commercially available.
[0035] Example 1 The fabrication process of the triboelectric power generation external field controlled MXene-PU SERS substrate is as follows: Step 1: Fabrication of multilayer Ti3C2T x MXene colloidal solution: Ti3C2T is prepared by in-situ generation of HF through mixing HCl and LiF, and selective etching of the Al atomic layer in the MAX ceramic phase (Ti3AlC2). x The MXene dispersion was prepared as follows: First, 20 mL of 9 mol / L hydrochloric acid solution was prepared and then transferred to a polytetrafluoroethylene container. 1.6 g of LiF was slowly added to the solution, and the mixture was stirred for 30 min using a water bath magnetic stirrer until completely dissolved. The temperature was set at 35℃ and the stirring speed at 400 rpm to obtain a mixed solution of HCl and LiF. 1 g of Ti3AlC2MAX precursor powder was weighed into the above mixed solution of HCl and LiF, being careful to add it slowly to avoid overheating. After stirring and etching at 35℃ for 24 h, the product was collected to finally obtain multilayer Ti3C2T. x MXene dispersion; prepared multilayer Ti3C2T x SEM images of MXene, such as Figure 1 As shown.
[0036] Step 2, monolayer Ti3C2T x Preparation of MXene colloidal solution: The multilayer Ti3C2T etched in step one... x The MXene dispersion was washed with 12 M hydrochloric acid at 8000 rpm for 10 min by centrifugation, and the supernatant was removed. This acid washing was repeated three times. The resulting precipitate was then washed repeatedly with deionized water by centrifugation for 10 min each time at 8000 rpm until the pH of the supernatant reached neutral. Centrifugation was stopped, the supernatant was discarded, and the lower, swollen, clay-like precipitate was collected. This precipitate was dispersed in deionized water and sonicated in an ice bath for 30 min using a 300 W ultrasonic cell disruptor. The sonicated solution was then centrifuged at 3500 rpm for 15 min, and the upper dark green colloidal solution was collected and stored at 4°C in the dark. The resulting monolayer Ti3C2T... x TEM images of MXene colloidal solutions are shown below. Figure 2 As shown.
[0037] Step 3, the microstructure of Ti3C2T dome xPreparation of MXene thin films: 40 mL of monolayer Ti3C2T from step two was used... x The MXene colloidal solution was centrifuged at 13000 rpm for 90 min to obtain Ti3C2T. x The MXene concentrate was coated onto a 20 mm × 20 mm hemispherical concave film of ethylene-vinyl acetate copolymer with a hemispherical diameter of 300 μm and a distribution array of 60 × 60. The film was then placed in a vacuum oven at 0.001 MPa for 2 min, removed, and dried at room temperature for 12 h. The resulting mold was then placed in anhydrous ethanol at 80 °C for 2 min, and after peeling, a flexible dome-shaped Ti3C2T microstructure was obtained. x MXene thin films, such as Figure 2 .
[0038] Step 4, Preparation of the dome-shaped microstructured PU film: 2 mL of a 40% solid content aqueous PU solution was dropped into a copper hemispherical concave film with dimensions of 20 mm × 20 mm, a hemispherical diameter of 300 μm, and a distribution array of 60 × 60. The film was placed in a vacuum oven with a vacuum degree of 0.001 MPa for 2 min, then removed and dried at room temperature for 12 h. The PU film was then peeled off to obtain a flexible dome-shaped microstructured PU film. Figure 3 .
[0039] Step 5, preparation of the triboelectric nanogenerator substrate under external field control: 15 cm long copper wires are led out from the films obtained in Step 3 and Step 4 for measuring electrical output, and the PU film is vertically covered on the Ti3C2Tx MXene film to assemble a triboelectric nanogenerator.
[0040] A controllable actuator was added to the assembled triboelectric generator (TGE) substrate with an externally controlled MXene-PU SERS substrate. The external vertical impact frequency was controlled at 2 Hz, and short-circuit current tests were conducted. Data were measured and analyzed using a DH7000 electrochemical workstation. The output voltage was measured under a 10 MΩ load condition, and the results are as follows: Figure 4 The test results show that under the control of an external vertical impact frequency of 2 Hz, the positive and negative friction layers can achieve contact separation, the short-circuit current is 294.5 nA, the output frequency is uniform and controllable, and the short-circuit current responds quickly, indicating that the device has good conductivity, which is conducive to the transfer of electrons in the conductive layer.
[0041] The open-circuit voltage of the assembled triboelectric power generation MXene-PU SERS substrate in this embodiment was tested by external vertical impact at a frequency of 1-5 Hz. The results are as follows: Figure 5The test results show that, under a fixed external vertical impact frequency, the positive and negative friction layers can achieve contact separation. When the impact frequency is 2 Hz, the open circuit voltage is 2.4 V, and a stable and continuous output is achieved.
[0042] Example 2 The preparation process of the triboelectric power generation external field-controlled MXene-PU SERS substrate is the same as in Example 1. The obtained triboelectric field-controlled MXene-PU SERS substrate was used to perform SERS tests on a rhodamine 6G solution, where the concentration of rhodamine 6G was 10%. -5 mol / L, Figure 6 The image shows the surface-enhanced Raman spectra of a triboelectric externally regulated MXene-PU SERS substrate at different external vertical impact frequencies. The image indicates that different external vertical impact frequencies result in varying signal enhancement for Rhodamine 6G on the triboelectric externally regulated MXene-PU SERS substrate, with the enhancement of Rhodamine 6G solution being optimal at an external vertical impact frequency of 2 Hz.
[0043] Example 3 The preparation process of the triboelectric power generation external field-controlled MXene-PU SERS substrate is the same as in Example 1. The obtained triboelectric external field-controlled MXene-PU SERS substrate was used to perform SERS tests on a rhodamine 6G solution, where the external vertical impact frequency was 2 Hz and the concentration of rhodamine 6G was 10%. -5 ~ 10 -8 mol / L, Figure 7 The surface-enhanced Raman spectra of different concentrations of rhodamine 6G on the triboelectric externally regulated MXene-PU SERS substrate are shown in the figures. The figures indicate that the detection limit of the triboelectric externally regulated MXene-PU SERS substrate prepared in this invention for rhodamine 6G solution reaches 10. -8 M.
[0044] Comparative Example 1 Compared with Example 1, this comparative example did not involve the preparation of a dome-shaped microstructure PU film. The remaining steps were the same as in Example 1, resulting in a triboelectric power generation external field-controlled MXene SERS substrate.
[0045] The obtained triboelectric field-controlled MXene SERS substrate was used to perform SERS tests on a rhodamine 6G solution with a rhodamine 6G concentration of 10. -5 mol / L, Figure 6The surface-enhanced Raman spectra of Rhodamine 6G on the triboelectric external field-controlled MXene SERS substrate are shown. The results indicate that the enhancement effect of the triboelectric external field-controlled MXene-PU SERS substrate prepared in this invention is much higher than that of the MXene SERS substrate composed solely of dome-shaped microstructure MXene films.
[0046] This invention describes preferred embodiments and their effects. However, those skilled in the art, upon learning the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the appended claims are intended to include both the preferred embodiments and all changes and modifications falling within the scope of this invention.
[0047] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.
Claims
1. A method for preparing a frictional power generation external field regulated MXene-PU SERS substrate, characterized in that, The method comprises the following steps: Step one, preparation of single-layer Ti3C2T x MXene colloidal solution; Step 2: The microstructure of Ti3C2T dome x Preparation of MXene thin films; the single-layer Ti3C2T x After concentration, the MXene colloidal solution was coated onto a hemispherical concave membrane of ethylene-vinyl acetate copolymer. It was then placed in a vacuum oven at 0.001 MPa to 0.01 MPa for 2 to 5 minutes, removed, and dried at room temperature. Subsequently, it was placed at a temperature of 60 to 90°C. o After peeling with anhydrous ethanol for 1-5 minutes, a flexible dome-shaped Ti3C2T microstructure was obtained. x MXene thin films; Step three, preparation of the dome microstructure PU film; drop the aqueous PU solution into the copper half-sphere concave film, place it in a vacuum oven with a vacuum degree of 0.001 MPa~0.01 MPa for 2~5 min, take it out, dry it at room temperature, and peel it off to obtain a flexible dome microstructure PU film; Step four, preparation of MXene-PU SERS substrate regulated by friction power generation field; the Ti3C2T x MXene film and the PU film each lead out an electrode, and the PU film is vertically covered on the Ti3C2T x MXene film is assembled into a friction nanogenerator above the MXene film; Step five, an external controllable clicker is added to the triboelectric nanogenerator, and the voltage and current output by the triboelectric nanogenerator are adjusted by controlling the hitting frequency of the controllable clicker.
2. The preparation method of the friction power generation external field regulated MXene-PU SERS substrate according to claim 1, characterized in that, The preparation of single-layer Ti3C2T x The process of MXene colloidal solution is: Step S1, uniformly disperse LiF in a hydrochloric acid solution to obtain a mixed solution of hydrochloric acid and LiF; Step S2, add Ti3AlC2 MAX precursor powder to the mixed solution of hydrochloric acid and LiF, stir and etch at 10~50℃ for 20~50 h, and then perform post-processing to obtain a clay-like precipitate; Step S3, uniformly dispersing the clay-like precipitate in deionized water, after ultrasonic and centrifugal, taking the upper colloidal solution, obtaining the monolayer Ti3C2T x MXene colloidal solution.
3. The preparation method of the friction power generation external field regulated MXene-PU SERS substrate according to claim 2, characterized in that, The concentration of the hydrochloric acid solution is 8-12 mol / L; the mass of the LiF is 0.5-5 g, the volume of the hydrochloric acid solution is 10-50 mL; the mass ratio of the Ti3AlC2 MAX precursor powder to the LiF is (0.5-3):(0.8-2.4); the monolayer Ti3C2T x The concentration of the MXene colloidal solution is 5-20 mg / mL.
4. The preparation method of the friction power generation external field regulated MXene-PU SERS substrate according to claim 2, characterized in that, The volume of the deionized water in step S3 is 10~50 mL; the ultrasonic process is to break the solution with an ultrasonic cell crusher under the condition of an ultrasonic power of 40~100 W for 20~60 min, the centrifugal speed is 1000~8000 rpm, and the centrifugal time is 10~50 min.
5. The preparation method of the friction power generation external field regulated MXene-PU SERS substrate according to claim 1, characterized in that, The monolayer Ti3C2T x In the process of concentrating the MXene colloidal solution, the monolayer Ti3C2T x The MXene colloidal solution is centrifuged at 10000-13000 rpm for 50-90 min to obtain Ti3C2T x MXene concentrated solution; the distribution array of the ethylene-vinyl acetate copolymer hemispherical concave film is 30×30-100×100, the diameter of the hemisphere is 100-500 μm, and the size is 10 mm×10 mm-50 mm×50 mm; and the time for room temperature drying is 10-20 h.
6. The preparation method of the friction power generation external field regulated MXene-PU SERS substrate according to claim 1, characterized in that, The volume of the aqueous PU solution in step three is 2~5 mL, the solid content is 30~50%, the distribution array of the copper half-sphere concave film is 30×30~100×100, the half-sphere diameter is 100~500 μm, the size is 10 mm×10 mm~50 mm×50 mm, and the room temperature drying time is 10~20 h.
7. The preparation method of the friction power generation external field regulated MXene-PU SERS substrate according to claim 1, characterized in that, The electrode in step four is a copper wire.
8. The preparation method of the friction power generation external field regulated MXene-PU SERS substrate according to claim 1, characterized in that, The hitting frequency of the controllable clicker in step five is 1~10 Hz.
9. A triboelectric power generation external field regulated MXene-PU SERS substrate prepared by the preparation method of any one of claims 1~8.
10. The application of the friction power generation external field regulation MXene-PU SERS substrate in SERS detection according to claim 9, characterized in that, The pressing frequency of the controllable clicker is controlled to realize the regulation of the Raman spectrum signal intensity of rhodamine 6G.