Preparation method and application of self-healing photoelectric gel based on Ti2CTX nanosheet

Abstract

The invention relates to a preparation method and application of self-healing photoelectric gel based on a Ti2CTx nanosheet. In the preparation process of the gel, the Ti2CTx nanosheet is crosslinked with a gel polymer network under the action of a crosslinking agent by utilizing the excellent mechanical property of the Ti2CTx nanosheet and abundant dangling bonds on the surface, so that the Ti2CTx nanosheet self-healing photoelectric gel is constructed. By adding the Ti2CTx nanosheet, the photoelectric property of the Ti2CTx nanosheet is integrated while the mechanical property of the gel is improved, and the self-healing photoelectric gel with excellent stretching and self-healing properties of the hydrogel and excellent photoelectric property of the Ti2CTx nanosheet is obtained. The organic gel disclosed by the invention has the characteristics of simple preparation process, short preparation period, low preparation cost, high environmental stability and the like; the material is applied to the field of photoelectric detection, a stretchable and self-healing photoelectric detector is prepared, and the application range of the MXene material and the photoelectric detector is further expanded.

Description

Technical field:

[0001] The present invention belongs to the field of flexible photoelectrochemical detection, and specifically relates to a method based on Ti2CT x Preparation method and application of self-healing photoelectric gel of nanosheets. Background technology:

[0002] In recent years, with the rapid development of artificial intelligence, the demand for human-computer interaction has been increasing; among them, flexible wearable electronic devices are the representatives of the new generation of electronic devices. Photodetectors are sensors that can receive light signals and process them into electrical signals. Photoelectrochemical photodetectors are a new type of photodetector that uses the interface effect of semiconductor and liquid contact to promote the generation of photogenerated charges; however, the liquid environment required for electrochemical photodetection has limited its further development to a certain extent; therefore, improving the entire component to obtain a multifunctional device that can adapt to multiple environments is of great significance.

[0003] Ti2CT x As a new type of two-dimensional layered semiconductor material, Ti2CT has broad application prospects in the field of photoelectric detection. x As a member of MXene, Ti2CT has a high specific surface area, excellent mechanical strength and abundant surface functional groups. x It can cross-link with hydrogel well to form a polymer network plus Ti2CT x The structure of nanosheets; MXene gel is used as a functional material in the electrochemical system to achieve the integration of semiconductor materials and solutions, and a wearable, stretchable, and self-healing photoelectric gel device is obtained. x The nanosheets are mixed in the PVA organic gel, cross-linked with the dangling bonds on the nanosheets through the organic gel network, and fully dispersed and fixed in the gel. The borate in the borax is then used to greatly enhance the self-healing properties of the gel, resulting in a stretchable, self-healing, photoelectrically functionalized organic gel, which greatly improves the application scenarios of photoelectrochemical photodetectors. Summary of the invention:

[0004] The purpose of the present invention is to provide a Ti2CT x Preparation method and application of self-healing photoelectric gel of nanosheets.

[0005] To achieve the above object, the present invention adopts the following technical solution:

[0006] The purpose of the present invention is to provide a Ti2CT xPreparation method and application of self-healing photoelectric gel of nanosheets. The organogel is obtained by uniformly mixing MXene nanosheets into PVA organogel by a simple heating and stirring method. The photodetector is Ti2CT x The photoelectrochemical photoelectric detector using nanosheet self-healing photoelectric gel as a functional material comprises the following steps:

[0007] 1) Dissolve LiF powder in a hydrochloric acid solution of a certain concentration, then add Ti2AlC powder into the LiF hydrochloric acid solution for etching, and then wash it repeatedly with dilute hydrochloric acid and deionized water to obtain the product Ti2CT x Dissolved in N-methyl-2-pyrrolidone solution and subjected to ultrasonic treatment; the obtained ultrasonically treated Ti2CT x The N-methyl-2-pyrrolidone solution was washed twice with acetone, anhydrous ethanol, and deionized water in sequence, and the peeled two-dimensional Ti2CT was obtained after drying. x Nanosheet samples;

[0008] 2) adding polyvinyl alcohol (PVA) powder and borax to ethylene glycol solution respectively, mixing on a heated stirring platform, and cooling naturally to obtain PVA / ethylene glycol solution and borax / ethylene glycol solution respectively; x The nanosheet sample was added to the PVA / ethylene glycol solution and heated and mixed evenly. Borax / ethylene glycol solution was added to maintain the temperature and mixed evenly. After natural cooling, Ti2CT x Nanosheet self-healing optoelectronic gel;

[0009] 3) The Ti2CT obtained in step 2) x The nanosheet self-healing photoelectric gel was loaded into a flexible substrate and led out with a copper wire as the output end. The electrochemical system was used to conduct photoelectric tests under different light intensities, different tensile variable states, and before and after self-healing to obtain Ti2CT x Performance of nanosheet self-healing optoelectronic gel.

[0010] According to the preferred embodiment of the present invention, in step 1), during the etching treatment, the mass of Ti2AlC powder is 500 mg, the mass of LiF is 800 mg, the concentration and volume of hydrochloric acid are 9 mol / L and 10 mL, respectively, and the etching treatment temperature and time are 45°C and 48 h, respectively; during the ultrasonic treatment, Ti2CT x The mass of the nanosheets is 200 mg, the volume of the N-methyl-2-pyrrolidone solution is 80 mL, the ultrasonic treatment time is 10 h, the cleaning time of acetone, anhydrous ethanol and deionized water is 20 min each, the drying temperature is -60 ° C, and the drying time is 24 h.

[0011] According to the preferred embodiment of the present invention, step 2) Ti2CTx The mass of nanosheets is 10 mg, the mass of PVA is 100 mg, the mass of borax is 50 mg, the volume of ethylene glycol in the PVA / ethylene glycol solution is 1 mL, the stirring temperature is 120 ° C, the stirring time is 5 min, and the cooling time is 30 min; the volume of ethylene glycol in the borax / ethylene glycol solution is 0.5 mL, the stirring temperature is 100 ° C, and the stirring time is 60 min; Ti2CT x The nanosheets were added to the PVA / ethylene glycol solution and stirred for 15 min at a temperature of 60 °C. The borax / ethylene glycol solution was added to the Ti2CT x The stirring time in the / PVA / ethylene glycol solution was 5 min and the stirring temperature was 60°C.

[0012] According to the preferred embodiment of the present invention, in step 3), the test gel is loaded on a 1×1 cm 2 In the groove, Ti2CT x The mass of the nanosheet self-healing photoelectric gel is 2 mg, the original length of the gel is 1 cm, the stretched lengths are 0 cm, 0.5 cm, and 1 cm, and the stretching degrees are 0%, 50%, and 100%, respectively. The gel and the substrate are cut in half, and after ensuring the circuit is broken, the gels are gently touched together to obtain the self-healed gel. The light intensity is 60, 90, 120, and 150 mW / cm 2 , the wavelength range of the excitation light source is 390-780nm.

[0013] All equipment and raw materials in the method of the present invention are commercially available products.

[0014] Based on the above technical solution, it can be seen that the present invention has the following advantages:

[0015] (1) A Ti2CT prepared by the present invention x Nanosheet self-healing photoelectric gel has good mechanical properties, good self-healing and stretchability under ambient conditions, and can change shape freely.

[0016] (2) The novel gel-type photodetector prepared by the present invention has a simple manufacturing process and low cost. A stretchable and self-healing photodetector device is realized, and it has an effective response under different light intensities and under different stretching conditions. Description of the drawings:

[0017] In order to more clearly illustrate the specific implementation of the present invention or the technical solution in the prior art, the following is a brief introduction to the drawings required for use in the specific implementation or the prior art description:

[0018] Figure 1 The Ti2CT prepared by the present invention xA physical picture of the nanosheet self-healing photoelectric gel, which shows that the broken gel can be completely healed and fully stretched after a short contact.

[0019] Figure 2 This is a physical picture of the gel photoelectric detection device prepared by the present invention, wherein the white part is a flexible substrate prepared by Ecoflex glue, and the black part is a self-healing photoelectric gel.

[0020] Figure 3 The Ti2CT prepared by the present invention x The photodetector of the nanosheet self-healing photoelectric gel is 60, 90, 120, 150 mW / cm 2 Graph of light response curves under light intensity.

[0021] Figure 4 The Ti2CT prepared by the present invention x Light response curves of the photodetector of the nanosheet self-healing photoelectric gel at stretching lengths of 0, 0.5, 1, 0.5, and 0 cm.

[0022] Figure 5 The Ti2CT prepared by the present invention x Light response curves of the photodetector of the nanosheet self-healing photoelectric gel before and after self-healing. Specific implementation method:

[0023] The present invention is further described in detail below by specific examples, wherein the raw materials are all industrial products. The examples are only used to explain the present invention and cannot be construed as limiting the present invention. Changes or modifications to the equivalent forms of the present invention by those skilled in the art also fall within the scope defined by the appended claims of the present application.

[0024] Embodiment 1:

[0025] The prepared flexible substrate gel device was connected to a standard three-electrode electrochemical system for testing. The gel was led out of the electrode with a copper wire. The counter electrode and the reference electrode on the electrochemical workstation were connected and connected to one side of the gel, and the other side was connected to the working electrode. A 350W xenon lamp was used as the illumination light source for the test. The illumination intensity was 60, 90, 120, and 150mW / cm 2 , under the condition of external bias voltage of 0.4V, the test is carried out by alternately illuminating and shielding with a cycle of 10s. Figure 3 As shown, as the light intensity increases from 60 to 150 mW / cm 2 Continuously enhanced, based on Ti2CT x The photocurrent of the photodetector of the nanosheet self-healing photoelectric gel increased from 0.125 to 0.245 μA / cm 2, proving that it can respond effectively to light of different intensities.

[0026] Embodiment 2:

[0027] The prepared flexible substrate gel device was connected to a standard three-electrode electrochemical system for testing. The gel was led out of the electrode with a copper wire. The counter electrode and the reference electrode on the electrochemical workstation were connected to one side of the gel and the other side was connected to the working electrode. A 350W xenon lamp was used as the illumination light source at a light intensity of 90mW / cm 2 , the external bias voltage is 0.2V, and the test is carried out under the conditions of stretching length of 0, 0.5, 1, 0.5, and 0cm, with alternating illumination and shading at a cycle of 10s. Figure 4 As shown, Ti2CT x The photocurrent of the photodetector of the nanosheet self-healing photoelectric gel gradually decreases when the stretching length is from 0 to 1 cm, but after the stretching is recovered, the photocurrent returns to its original state; at the same time, it still maintains good photoelectric detection performance when the stretching degree is maximum.

[0028] Example 3

[0029] The prepared flexible substrate gel device was connected to a standard three-electrode electrochemical system for testing. The gel was led out of the electrode with a copper wire. The counter electrode and the reference electrode on the electrochemical workstation were connected to one side of the gel and the other side was connected to the working electrode. A 350W xenon lamp was used as the illumination light source at a light intensity of 90mW / cm 2 Under the condition of 0.4V external bias, the gel before and after self-healing was tested by alternating illumination and shading with a cycle of 10s. Figure 5 As shown, Ti2CT x The photocurrent of the photodetector of the nanosheet self-healing photoelectric gel instantly becomes 0 when it is cut off. The moment the gel is contacted again, the path is restored and the photocurrent is tested again. The photocurrent before and after self-healing is generated instantly. Although the response decreases slightly, it still shows excellent self-healing properties.

Claims

1. A method based on Ti2CT x The preparation method and application of the self-healing photoelectric gel of nanosheets include the following steps: 1) Dissolve LiF powder in a hydrochloric acid solution of a certain concentration, then add Ti2AlC powder into the LiF-hydrochloric acid solution for etching. The etched product is repeatedly washed with dilute hydrochloric acid and deionized water in turn. x Dissolved in N-methyl-2-pyrrolidone solution and subjected to ultrasonic treatment; the obtained ultrasonically treated Ti2CT x The N-methyl-2-pyrrolidone solution was washed twice with acetone, anhydrous ethanol, and deionized water in sequence, and the peeled two-dimensional Ti2CT was obtained after drying. x Nanosheet samples; 2) adding polyvinyl alcohol (PVA) powder and borax to ethylene glycol solution respectively, mixing using a heated stirring table, and cooling naturally to obtain PVA / ethylene glycol solution and borax / ethylene glycol solution respectively; x The nanosheet sample was added to the PVA / ethylene glycol solution and heated and mixed evenly. Borax / ethylene glycol solution was added to maintain the temperature and mixed evenly. After natural cooling, Ti2CT x Nanosheet self-healing optoelectronic gel; 3) The Ti2CT obtained in step 2) x The nanosheet self-healing photoelectric gel was loaded into a flexible substrate and led out with a copper wire as the output end. The electrochemical system was used to conduct photoelectric tests under different light intensities, different tensile variable states, and before and after self-healing to obtain Ti2CT x Performance of nanosheet self-healing optoelectronic gel.

2. A Ti2CT based method according to claim 1 x The preparation method and application of nanosheet self-healing photoelectric gel are characterized in that: In step 1), during the etching process, the mass of Ti2AlC powder is 500 mg, the mass of LiF is 800 mg, the concentration and volume of hydrochloric acid are 9 mol / L and 10 mL, respectively, and the etching temperature and time are 45°C and 48 h, respectively; during the ultrasonic treatment, Ti2CT x The mass of the nanosheets is 200 mg, the volume of the N-methyl-2-pyrrolidone solution is 80 mL, the ultrasonic treatment time is 10 h, the cleaning time of acetone, anhydrous ethanol and deionized water is 20 min each, the drying temperature is -60 ° C, and the drying time is 24 h.

3. A Ti2CT based method according to claim 1 x The preparation method and application of nanosheet self-healing photoelectric gel are characterized in that: In step 2), Ti2CT x The mass of nanosheets is 10 mg, the mass of PVA is 100 mg, the mass of borax is 50 mg, the volume of ethylene glycol in the PVA / ethylene glycol solution is 1 mL, the stirring temperature is 120 ° C, the stirring time is 5 min, and the cooling time is 30 min; the volume of ethylene glycol in the borax / ethylene glycol solution is 0.5 mL, the stirring temperature is 100 ° C, and the stirring time is 60 min; Ti2CT x The nanosheets were added to the PVA / ethylene glycol solution and stirred for 15 min at a temperature of 60 °C. The borax / ethylene glycol solution was added to the Ti2CT x The stirring time in the / PVA / ethylene glycol solution was 5 min and the stirring temperature was 60°C.

4. A Ti2CT based method according to claim 1 x The preparation method and application of nanosheet self-healing photoelectric gel are characterized in that: In step 3), the test gel was loaded on a 1×1 cm 2 In the groove, Ti2CT x The mass of the nanosheet self-healing photoelectric gel is 2 mg, the original length of the gel is 1 cm, the stretched lengths are 0, 0.5, and 1 cm, and the stretching degrees are 0%, 50%, and 100%, respectively. The gel and the substrate are cut in half, and after ensuring the circuit is broken, the gels are gently touched together to obtain the self-healed gel. The light intensity is 60, 90, 120, and 150 mW / cm 2 , the wavelength range of the excitation light source is 390-780nm.

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