Textile-based flexible temperature sensing interdigitated electrode and its preparation method and use

Abstract

A kind of textile-based flexible temperature sensing interdigital electrode and its preparation method and use belong to the field of material science and technology.It includes: MXene dispersion liquid is obtained by etching Ti 3 AlC 2 with hydrofluoric acid, and is prepared by delamination and drying;AgNWs dispersion liquid is synthesized by hydrothermal method;MXene / AgNPs composite dispersion liquid is prepared by adding silver nitrate solution into MXene dispersion liquid;AgNWs dispersion liquid, composite dispersion liquid and temperature-responsive ionic liquid are mixed into conductive slurry, and the sensing yarn is obtained by impregnation treatment of modified strong yarn;finally, the yarn is compounded on the textile substrate in the form of interdigital electrode.The interdigital electrode prepared by the method has the advantages of high sensitivity, good conductivity and accurate monitoring of vital signs, and has potential applications in the fields of artificial skin and wearable temperature sensing devices.

Description

Technical Field

[0001] This invention belongs to the field of materials science and technology, specifically a textile-based flexible temperature sensing interdigital electrode, its preparation method, and its applications. Background Technology

[0002] In the 1960s, MIT proposed the concept of wearable technology, which involves embedding microchips and other hardware systems into flexible materials using digital sensing and communication technologies for direct wear by the human body, enabling interaction with the outside world. Wearable devices are an interdisciplinary product of computer science, signal transmission, mechatronics, and textiles, making their development relatively challenging. The fabrication of flexible electronic fabrics that offer high flexibility, stable signal transmission, and maintain their mechanical properties is currently a research hotspot in the wearable field. Furthermore, media used for signal transmission between wearable devices, such as wired metal wires and wireless transmission modules, suffer from high rigidity and difficulty in bending and folding, affecting wearability and comfort. Based on these issues, textile-based signal transmission media for wearables hold promise for further advancing the development of intelligent wearable devices. Interdigital electrodes have already played an important role in the fields of sensing, communication, control, and actuation. Textile-based interdigital electrodes for wearable devices are expected to further replace traditional interdigital electrodes in terms of improving wearing comfort. They are suitable for a wide range of people, serving as professional devices for special groups such as athletes and patients, as well as improving the lifestyle and quality of life of the general public. They are widely used in fields such as electronic skin, national defense, and medical rehabilitation, and are of great significance to the development and progress of modern society.

[0003] Textile-based interdigital electrodes possess inherent flexibility, enabling both signal transmission to the external environment and monitoring of the wearer's vital signs. This is particularly relevant given the rapid increase in the aging population and the number of people in a sub-healthy state; wearable devices are crucial for sensing and monitoring body temperature. Therefore, the research and development of textile-based interdigital electrodes with both temperature sensing and communication functions is significant. However, the accuracy of current textile-based interdigital electrodes needs improvement, and the integration of temperature sensing functionality is challenging—key issues that urgently need to be addressed.

[0004] In recent years, novel materials such as graphene and carbon nanotubes have been increasingly recognized for their excellent mechanical, electrical, and optical properties, leading to their widespread application in various research fields. Compared to graphene, novel two-dimensional transition metal carbides (nitrides), MXene, since its successful preparation in 2011, not only possesses graphene-like properties but also exhibits metal-like high conductivity and high energy density. Furthermore, its products demonstrate good energy storage, hydrogen storage, and electromagnetic shielding performance. Silver nanowires and nanoparticles, among other metallic nanomaterials, possess both the high conductivity of elemental silver and the unique surface and interface effects of nanomaterials. Their morphology is controllable, their dimensions are tunable, and they readily couple with two-dimensional MXene. When combined with conventional fabrics, these three materials exhibit higher electrical and thermal conductivity, as well as excellent temperature sensing characteristics, making them the preferred materials for fabricating textile-based interdigitated electrodes. Summary of the Invention

[0005] To address the aforementioned problems in the existing technology, the present invention aims to design and provide a technical solution for a textile-based flexible temperature sensing interdigital electrode, its preparation method, and its applications. The interdigital electrode prepared by this method has simple processing, low cost, and advantages such as high sensitivity, good conductivity, and accurate monitoring of vital signs. It has potential applications in fields such as artificial skin and wearable temperature sensing devices.

[0006] The method for preparing a textile-based flexible temperature sensing interdigital electrode is characterized by comprising the following steps: (1) Ti3AlC2 was directly etched with a hydrofluoric acid or fluoride salt solution with a concentration of 5% to 40% for 8 to 36 hours and at a temperature of 24 to 40°C. After centrifugation and washing, a dispersion of multilayer MXene nanosheets was obtained. (2) Add the layer-expanding agent to the dispersion obtained in step (1), the layer-expanding time is 18-24h, the temperature is 24-40℃, and the solution is centrifuged again to remove the layer-expanding agent, and the exfoliated MXene nanosheet dispersion is obtained; (3) The MXene nanosheet dispersion obtained in step (2) is subjected to solid-liquid separation and drying to obtain MXene powder; (4) Using the hydrothermal synthesis method, polyvinylpyrrolidone and silver nitrate are added to ethylene glycol. After stirring in the dark, sodium chloride is added and heated at 140-170℃ for 1-3 hours. Other impurities are removed by centrifugation and filtration in methanol or ethanol. Finally, it is dispersed in ethanol or methanol to obtain a uniform and stable AgNWs dispersion. (5) Slowly drop AgNO3 solution with a concentration of 5-40 mM into MXene dispersion with a concentration of 50-200 mg / mL prepared by redispersing MXene powder obtained in step (3) at room temperature. The volume ratio of AgNO3 solution to MXene dispersion is 5-15:8-12. Sonicate for 5-20 minutes to form a MXene / AgNPs composite dispersion with uniform particle size. (6) The AgNWs dispersion obtained in step (4), the MXene / AgNPs composite dispersion obtained in step (5), and the temperature-responsive ionic liquid are mixed in a volume ratio of 6-3:3-1:1-6 to obtain a composite conductive slurry; then, the high-strength yarn is plasma etched and then immersed in the composite conductive slurry, treated and dried to obtain a temperature-sensing conductive yarn. (7) The temperature sensing conductive yarn obtained in step (6) is laminated onto the textile substrate with an interdigitated electrode pattern to obtain the textile substrate flexible temperature sensing interdigitated electrode.

[0007] The method for preparing a textile-based flexible temperature-sensing interdigitated electrode is characterized in that, in step (1): the concentration of hydrofluoric acid or fluoride salt solution is 10%–30%, preferably 15%–20%; the etching time is 15–30 h, preferably 20–25 h; the etching temperature is 26–35 °C, preferably 30–32 °C; the volume-to-mass ratio of hydrofluoric acid or fluoride salt solution to Ti3AlC2 is 10–40 ml: 0.2–1.0 g, preferably 20–30 ml: 0.5–0.8 g; the solution is centrifuged and washed until the pH value is 6–7; the fluoride salt solution is prepared by adding lithium fluoride to hydrochloric acid.

[0008] The method for preparing a textile-based flexible temperature-sensing interdigitated electrode is characterized in that, in step (2): the layer-expanding agent is at least one of dimethyl sulfoxide, sodium chloride, and potassium chloride; the layer-expanding time is 20-22 h, and the temperature is 30-35 °C; the centrifugation speed for removing the layer-expanding agent is 6000-10000 rpm, with the goal of basically removing the layer-expanding agent; argon gas is introduced during centrifugation for protection to prevent MXene from being oxidized. The dimethyl sulfoxide (DMSO) has a long molecular chain and rich folded structure, making it suitable as a layer-expanding agent to increase the distance between MXene layers.

[0009] The method for preparing a textile-based flexible temperature sensing interdigitated electrode is characterized in that the solid-liquid separation and drying in step (3) specifically involves vacuum drying after filtration at a temperature of 24–36°C.

[0010] The method for preparing a textile-based flexible temperature sensing interdigitated electrode is characterized in that, in step (4): the amount of ethylene glycol is 10-30 ml, the amount of polyvinylpyrrolidone is 0.3-0.6 g, the amount of silver nitrate is 0.15-0.3 g, and the amount of sodium chloride is 0.01-0.03 mmol; the heating temperature is 150-160℃ for 2 h.

[0011] The method for preparing a textile-based flexible temperature-sensing interdigitated electrode is characterized in that, in step (5): the concentration of AgNO3 solution is 10-30 mM, preferably 15-20 mM; the concentration of MXene dispersion is 80-150 mg / mL, preferably 100-120 mg / mL; the volume ratio of AgNO3 solution to MXene dispersion is 8-10:10-11; and the ultrasonic oscillation time is 10-15 minutes.

[0012] The method for preparing a textile-based flexible temperature-sensing interdigitated electrode is characterized in that, in step (6): the volume ratio of AgNWs dispersion: MXene / AgNPs composite dispersion: temperature-responsive ionic liquid is 5-4:2-1.5:2-4; the temperature-responsive ionic liquid is 1-ethyl-3-methylimidazolium tetrafluoroborate, 1-ethyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide, 1-hexyl-2,3-dimethylimidazolium hexafluorophosphate, At least one of 1,2-dimethyl-3-hydroxyethylimidazolium p-methylbenzenesulfonate; the strong yarn is polyester, nylon or cotton yarn with a fineness of 200-600D; before or after plasma etching, the strong yarn is coated with polydopamine; the polydopamine coating treatment specifically involves: placing the yarn in a Tris-HCl buffer solution with a pH of ≈8.5, adding dopamine hydrochloride to a concentration of 10-30 mg / L, allowing it to stand for 18-48 hours, and then drying it.

[0013] The method for preparing a textile-based flexible temperature sensing interdigital electrode is characterized in that, in step (7): the textile substrate is a knitted fabric, woven fabric, or nonwoven fabric; the composite method is sewing, weaving, or embroidery. The size of the flexible fabric is not limited to 10mm × 20mm, and different sizes and shapes of fabrics are woven according to the monitoring requirements of different parts of the human body.

[0014] The textile-based flexible temperature sensing interdigital electrode is characterized in that it is prepared by any one of the above-described preparation methods.

[0015] This invention relates to the application of a textile-based flexible temperature-sensing interdigital electrode in the fabrication of wearable temperature-sensing devices. The textile-based multifunctional temperature-sensing interdigital electrode prepared by this invention has a temperature response range of 25–80°C and a temperature coefficient of resistance of 2–4 × 10⁻⁶. -3 / ℃.

[0016] Compared with the prior art, the beneficial effects of the present invention are as follows: (1) The present invention synthesizes MXene silver nanocomposite material with simple preparation process and low cost. Among them, AgNPs can be uniformly dispersed in the interior and surface of MXene nanosheets, which further improves the conductivity and flexibility of MXene; AgNWs, as a bridge between MXene and AgNPs, improve the conductivity continuity and stability of yarn and interdigitated electrodes.

[0017] (2) The present invention uses strong yarn, which is improved by hydrophilicity through polydopamine and plasma etching, making it easier for the nanocomposite material to adhere to the yarn. It is not easy to fall off during yarn deformation, friction and weaving process, and has high fastness.

[0018] (3) The multifunctional temperature sensing interdigital electrode prepared by the present invention can monitor temperature changes over a wide range, monitor human body temperature signs, has high sensitivity, accurate data, and is convenient to monitor. Attached Figure Description

[0019] Figure 1 This is a process flow diagram of a typical embodiment of the present invention for preparing a multidimensional nanocomposite material based on MXene / Silver; Figure 2 The image shows a scanning electron microscope (SEM) image of the MXene prepared in Example 1. Figure 3 This is a scanning electron microscope image of the yarn surface prepared in Example 1; Figure 4 Design and actual effect diagram of interdigital electrodes. Detailed Implementation

[0020] The present invention will be further illustrated below with reference to specific embodiments. It should be understood that these embodiments are for illustrative purposes only and are not intended to limit the scope of the invention. Furthermore, it should be understood that after reading the teachings of this invention, those skilled in the art can make various alterations or modifications to the invention, and these equivalent forms also fall within the scope defined by the appended claims.

[0021] All raw materials used in the following examples are commercially available products. Example 1

[0022] Step 1: 30 ml of 35% HF was used to directly etch Ti3AlC2 at room temperature for 24 h. The resulting solution was centrifuged, peeled off, and washed until pH≈6 to obtain multilayer MXene nanosheets. Step 2: Slowly add 8 ml of DMSO dropwise to the centrifuged dispersion. The expansion time is 24 h and the temperature is 30 °C. Centrifuge the solution again, peel off and wash until the DMSO is removed. Step 3: The prepared MXene dispersion is vacuum filtered and vacuum dried at 30°C to make MXene powder for further use; Step 4: Using the hydrothermal synthesis method, 0.45g PVP and 0.2g AgNO3 were added to 20ml EG. After stirring in the dark, 0.01mmol NaCl was added and heated at 170℃ for 2h. After cooling, centrifugation and filtration were used to remove other impurities. Finally, it was dispersed in 20ml ethanol to obtain a uniform and stable AgNWs dispersion. Step 5: Slowly add 10 ml of 10 mM AgNO3 solution to the redispersed 150 mg / mL MXene dispersion at room temperature, and sonicate for 10 minutes to form AgNPs with uniform particle size. Step 6: Mix AgNWs in a ratio of 6:3:1 with MXene dispersion containing AgNPs, and then impregnate high-strength yarn with a fineness of 200D with plasma etching to obtain a yarn temperature sensor with high sensing characteristics. Step 7: Fabrication of wearable devices: After vacuum drying the impregnated yarn, combine it with a textile substrate to construct interdigitated electrodes, giving them temperature sensing characteristics, thereby fabricating a highly sensitive textile-based flexible sensor.

[0023] The resulting textile-based temperature-sensing interdigital electrode wristband exhibits high adhesion of the nanocomposite material and a temperature coefficient of resistance of 2.65 × 10⁻⁶. -3 It has a temperature of / ℃ and does not exhibit fatigue even after 1000 cycles of use, with accurate temperature sensing. Example 2

[0024] Step 1: 30 ml of 30% HF was used to directly etch Ti3AlC2 at 30°C for 24 h. The resulting solution was centrifuged, peeled off, and washed until pH≈6 to obtain multilayer MXene nanosheets. Step 2: Slowly add 12 ml of DMSO dropwise to the centrifuged dispersion. The layer expansion time is 18 h and the temperature is 24 °C. Centrifuge the solution again, and perform peeling and washing until the DMSO is removed. Step 3: The prepared MXene dispersion is vacuum filtered and vacuum dried at 30°C to make MXene powder for further use; Step 4: Using the hydrothermal synthesis method, 0.45g PVP and 0.2g AgNO3 were added to 20ml EG. After stirring in the dark, 0.01mmol NaCl was added and heated at 170℃ for 2h. After cooling, centrifugation and filtration were used to remove other impurities. Finally, it was dispersed in 20ml ethanol to obtain a uniform and stable AgNWs dispersion. Step 5: Slowly add 10 ml of 10 mM AgNO3 solution to the redispersed 200 mg / mL MXene dispersion at room temperature, and sonicate for 10 minutes to form AgNPs with uniform particle size. Step 6: Mix AgNWs in a ratio of 6:3:1 with MXene dispersion containing AgNPs, and then impregnate high-strength yarn with a fineness of 200D with plasma etching to obtain a yarn temperature sensor with high sensing characteristics. Step 7: Fabrication of wearable devices: After vacuum drying the impregnated yarn, combine it with a textile substrate to construct interdigitated electrodes, enabling it to simultaneously monitor gas, sweat, and temperature, thereby fabricating a highly sensitive textile-based flexible sensor.

[0025] The resulting textile-based temperature-sensing interdigital electrode patch behind the ear exhibits high adhesion of the nanocomposite material and a temperature coefficient of resistance of 2.73 × 10⁻⁶. -3 It has a temperature of / ℃ and does not exhibit fatigue even after 1000 cycles of use, with accurate temperature sensing. Example 3

[0026] Step 1: 30 ml of 40% HF was used to directly etch Ti3AlC2 at 30°C for 15 h. The resulting solution was centrifuged, peeled off, and washed until pH≈6 to obtain multilayer MXene nanosheets. Step 2: Slowly add 10 ml of DMSO dropwise to the centrifuged dispersion. The layer expansion time is 18 h and the temperature is 24 °C. Centrifuge the solution again, peel off and wash until the DMSO is removed. Step 3: The prepared MXene dispersion is vacuum filtered and vacuum dried at 30°C to make MXene powder for further use; Step 4: Using the hydrothermal synthesis method, 0.4g PVP and 0.2g AgNO3 were added to 15ml EG, and after stirring in the dark, 0.01mmol NaCl was added and heated at 170℃ for 1h. After cooling, centrifugation and filtration were used to remove other impurities. Finally, it was dispersed in 20ml ethanol to obtain a uniform and stable AgNWs dispersion. Step 5: Slowly add 10 ml of 20 mM AgNO3 solution to the redispersed 100 mg / mL MXene dispersion at room temperature, and sonicate for 10 minutes to form AgNPs with uniform particle size. Step 6: Mix AgNWs in a ratio of 6:3:1 with MXene dispersion containing AgNPs, and then impregnate high-strength yarn with a fineness of 400D with plasma etching to obtain a yarn temperature sensor with high sensing characteristics. Step 7: Fabrication of wearable devices: After vacuum drying the impregnated yarn, combine it with a textile substrate to construct interdigitated electrodes, giving them temperature sensing characteristics, thereby fabricating a highly sensitive textile-based flexible sensor.

[0027] The resulting textile-based temperature-sensing interdigital electrode wristband exhibits high adhesion of the nanocomposite material and a temperature coefficient of resistance of 3.12 × 10⁻⁶. -3 It has a temperature of / ℃ and does not exhibit fatigue even after 1000 cycles of use, with accurate temperature sensing. Example 4

[0028] Step 1: 30 ml of 15% HF was used to directly etch Ti3AlC2 at 30°C for 30 h. The resulting solution was centrifuged, peeled off, and washed until pH≈6 to obtain multilayer MXene nanosheets. Step 2: Slowly add 12 ml of DMSO dropwise to the centrifuged dispersion. The layer expansion time is 18 h and the temperature is 24 °C. Centrifuge the solution again, and perform peeling and washing until the DMSO is removed. Step 3: The prepared MXene dispersion is vacuum filtered and vacuum dried at 30°C to make MXene powder for further use; Step 4: Using the hydrothermal synthesis method, 0.55g PVP and 0.25g AgNO3 were added to 20ml EG. After stirring in the dark, 0.02mmol NaCl was added and heated at 170℃ for 3h. After cooling, centrifugation and filtration were used to remove other impurities. Finally, it was dispersed in 20ml ethanol to obtain a uniform and stable AgNWs dispersion. Step 5: Slowly add 10 ml of 20 mM AgNO3 solution to the redispersed 100 mg / mL MXene dispersion at room temperature, and sonicate for 10 minutes to form AgNPs with uniform particle size. Step 6: Mix AgNWs in a ratio of 6:3:1 with MXene dispersion containing AgNPs, and then impregnate high-strength yarn with a fineness of 600D with plasma etching to obtain a yarn temperature sensor with high sensing characteristics. Step 7: Fabrication of wearable devices: After vacuum drying the impregnated yarn, combine it with a textile substrate to construct interdigitated electrodes, giving them temperature sensing characteristics, thereby fabricating a highly sensitive textile-based flexible sensor.

[0029] The resulting textile-based temperature-sensing interdigital electrode patch behind the ear exhibits high adhesion of the nanocomposite material and a temperature coefficient of resistance of 2.84 × 10⁻⁶. -3 It has a temperature of / ℃ and does not exhibit fatigue even after 1000 cycles of use, with accurate temperature sensing. Example 5

[0030] Step 1: 30 ml of 35% HF was used to directly etch Ti3AlC2 at 30°C for 36 h. The resulting solution was centrifuged, peeled off, and washed until pH≈6 to obtain multilayer MXene nanosheets. Step 2: Slowly add 12 ml of DMSO dropwise to the centrifuged dispersion. The layer expansion time is 24 h and the temperature is 30 °C. Centrifuge the solution again, peel off and wash until the DMSO is removed. Step 3: The prepared MXene dispersion is vacuum filtered and vacuum dried at 30°C to make MXene powder for further use; Step 4: Using the hydrothermal synthesis method, 0.5g PVP and 0.3g AgNO3 were added to 20ml EG, and after stirring in the dark, 0.02mmol NaCl was added and heated at 170℃ for 3h. After cooling, centrifugation and filtration were used to remove other impurities. Finally, it was dispersed in 20ml ethanol to obtain a uniform and stable AgNWs dispersion. Step 5: Slowly add 10 ml of 30 mM AgNO3 solution to the redispersed 200 mg / mL MXene dispersion at room temperature, and sonicate for 15 minutes to form AgNPs with uniform particle size. Step 6: Mix AgNWs in a ratio of 6:3:1 with MXene dispersion containing AgNPs, and then impregnate high-strength yarn with a fineness of 450D with plasma etching to obtain a yarn temperature sensor with high sensing characteristics. Step 7: Fabrication of wearable devices: After vacuum drying the impregnated yarn, combine it with a textile substrate to construct interdigitated electrodes, giving them temperature sensing characteristics, thereby fabricating a highly sensitive textile-based flexible sensor.

[0031] The resulting textile-based temperature-sensing interdigital electrode patch behind the ear exhibits high adhesion of the nanocomposite material and a temperature coefficient of resistance of 3.35 × 10⁻⁶. -3 It has a temperature of / ℃ and does not exhibit fatigue even after 1000 cycles of use, with accurate temperature sensing. Example 6

[0032] Step 1: 30 ml of 35% HF was used to directly etch Ti3AlC2 at 32°C for 24 h. The resulting solution was centrifuged, peeled off, and washed until pH≈6 to obtain multilayer MXene nanosheets. Step 2: Slowly add 12 ml of DMSO dropwise to the centrifuged dispersion. The layer expansion time is 24 h and the temperature is 36 °C. Centrifuge the solution again, peel off and wash until the DMSO is removed. Step 3: The prepared MXene dispersion is vacuum filtered and vacuum dried at 30°C to make MXene powder for further use; Step 4: Using the hydrothermal synthesis method, 0.3g PVP and 0.3g AgNO3 were added to 20ml EG, and after stirring in the dark, 0.01mmol NaCl was added and heated at 170℃ for 2h. After cooling, centrifugation and filtration were used to remove other impurities. Finally, it was dispersed in 20ml ethanol to obtain a uniform and stable AgNWs dispersion. Step 5: Slowly add 10 ml of 40 mM AgNO3 solution to the redispersed 150 mg / mL MXene dispersion at room temperature, and sonicate for 15 minutes to form AgNPs with uniform particle size. Step 6: Mix AgNWs in a ratio of 5:3:2 with MXene dispersion containing AgNPs, and then impregnate 300D high-strength yarn with plasma etching to obtain a yarn temperature sensor with high sensing characteristics. Step 7: Fabrication of wearable devices: After vacuum drying the impregnated yarn, combine it with a textile substrate to construct interdigitated electrodes, giving them temperature sensing characteristics, thereby fabricating a highly sensitive textile-based flexible sensor.

[0033] The resulting textile-based temperature-sensing interdigital electrode wristband exhibits high adhesion of the nanocomposite material and a temperature coefficient of resistance of 3.23 × 10⁻⁶. -3 It has a temperature of / ℃ and does not exhibit fatigue even after 1000 cycles of use, with accurate temperature sensing. Example 7

[0034] Step 1: 30 ml of 35% HF was used to directly etch Ti3AlC2 at 36°C for 24 h. The resulting solution was centrifuged, peeled off, and washed until pH≈6 to obtain multilayer MXene nanosheets. Step 2: Slowly add 15 ml of DMSO dropwise to the centrifuged dispersion. The layer expansion time is 24 h and the temperature is 30 °C. Centrifuge the solution again, and perform peeling and washing until the DMSO is removed. Step 3: The prepared MXene dispersion is vacuum filtered and vacuum dried at 30°C to make MXene powder for further use; Step 4: Using the hydrothermal synthesis method, 0.4g PVP and 0.2g AgNO3 were added to 20ml EG, and after stirring in the dark, 0.01mmol NaCl was added and heated at 170℃ for 2h. After cooling, centrifugation and filtration were used to remove other impurities. Finally, it was dispersed in 20ml ethanol to obtain a uniform and stable AgNWs dispersion. Step 5: Slowly add 10 ml of 30 mM AgNO3 solution to the redispersed 100 mg / mL MXene dispersion at room temperature, and sonicate for 15 minutes to form AgNPs with uniform particle size. Step 6: Mix AgNWs in a ratio of 4:3:3 with MXene dispersion containing AgNPs, and then impregnate high-strength yarn with a fineness of 300D with plasma etching to obtain a yarn temperature sensor with high sensing characteristics. Step 7: Fabrication of wearable devices: After vacuum drying the impregnated yarn, combine it with a textile substrate to construct interdigitated electrodes, giving them temperature sensing characteristics, thereby fabricating a highly sensitive textile-based flexible sensor.

[0035] The resulting textile-based temperature-sensing interdigitated electrode exhibits high adhesion to the nanocomposite material and a temperature coefficient of resistance of 2.94 × 10⁻⁶. -3 It has a temperature of / ℃ and does not exhibit fatigue even after 1000 cycles of use, with accurate temperature sensing.

[0036] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the implementation of the present invention. For those skilled in the art, other variations or modifications can be made based on the above description. It is impossible to exhaustively list all the implementation methods here. All obvious variations or modifications derived from the technical solutions of the present invention are still within the protection scope of the present invention.

Claims

1. A method for preparing a textile-based flexible temperature-sensing interdigitated electrode, characterized in that... Includes the following steps: (1) Ti3AlC2 was directly etched with a hydrofluoric acid or fluoride salt solution with a concentration of 5% to 40% for 8 to 36 hours and at a temperature of 24 to 40°C. After centrifugation and washing, a dispersion of multilayer MXene nanosheets was obtained. (2) Add the layer-expanding agent to the dispersion obtained in step (1), the layer-expanding time is 18-24h, the temperature is 24-40℃, and the solution is centrifuged again to remove the layer-expanding agent, and the exfoliated MXene nanosheet dispersion is obtained; (3) The MXene nanosheet dispersion obtained in step (2) is subjected to solid-liquid separation and drying to obtain MXene powder; (4) Using the hydrothermal synthesis method, polyvinylpyrrolidone and silver nitrate were added to ethylene glycol, and after stirring in the dark, sodium chloride was added and heated at 140-170℃ for 1-3 hours. After centrifugation and washing with methanol or ethanol, the AgNWs dispersion was obtained. (5) Slowly add a 5-40 mM AgNO3 solution at room temperature to an MXene dispersion with a concentration of 50-200 mg / mL prepared by redispersing the MXene powder obtained in step (3). The volume ratio of AgNO3 solution to MXene dispersion is 5-15:8-12. Sonicate for 5-20 minutes to form an MXene / AgNPs composite dispersion. (6) The AgNWs dispersion obtained in step (4), the MXene / AgNPs composite dispersion obtained in step (5), and the temperature-responsive ionic liquid are mixed in a volume ratio of 6-3:3-1:1-6 to obtain a composite conductive slurry; then, the high-strength yarn is plasma etched and then immersed in the composite conductive slurry, treated and dried to obtain a temperature-sensing conductive yarn. (7) The temperature sensing conductive yarn obtained in step (6) is laminated onto the textile substrate with an interdigitated electrode pattern to obtain the textile substrate flexible temperature sensing interdigitated electrode.

2. The method for preparing a textile-based flexible temperature sensing interdigitated electrode as described in claim 1, characterized in that... In step (1): the concentration of hydrofluoric acid or fluoride salt solution is 10% to 30%, preferably 15% to 20%; the etching time is 15 to 30 h, preferably 20 to 25 h; the etching temperature is 26 to 35 °C, preferably 30 to 32 °C; the volume-to-mass ratio of hydrofluoric acid or fluoride salt solution to Ti3AlC2 is 10-40 ml: 0.2-1.0 g, preferably 20-30 ml: 0.5-0.8 g; centrifugation and washing until the pH of the solution is 6-7; the fluoride salt solution is prepared by adding lithium fluoride to hydrochloric acid.

3. The method for preparing a textile-based flexible temperature-sensing interdigitated electrode as described in claim 1, characterized in that... In step (2): the layer expansion agent is at least one of dimethyl sulfoxide, sodium chloride, and potassium chloride; the layer expansion time is 20-22h, and the temperature is 30-35℃; the centrifugation speed for removing the layer expansion agent is 6000-10000rpm, with the goal of basically removing the layer expansion agent; argon gas is introduced during the centrifugation process for protection to prevent MXene from being oxidized.

4. The method for preparing a textile-based flexible temperature-sensing interdigitated electrode as described in claim 1, characterized in that... The solid-liquid separation and drying in step (3) specifically involves vacuum drying after filtration at a temperature of 24–36°C.

5. The method for preparing a textile-based flexible temperature-sensing interdigitated electrode as described in claim 1, characterized in that... In step (4): the amount of ethylene glycol is 10-30 ml, the amount of polyvinylpyrrolidone is 0.3-0.6 g, the amount of silver nitrate is 0.15-0.3 g, and the amount of sodium chloride is 0.01-0.03 mmol; the heating temperature is 150-160℃ and the heating time is 2 h.

6. The method for preparing a textile-based flexible temperature sensing interdigitated electrode as described in claim 1, characterized in that... In step (5): the concentration of AgNO3 solution is 10-30mM, preferably 15-20mM; the concentration of MXene dispersion is 80-150mg / mL, preferably 100-120mg / mL; the volume ratio of AgNO3 solution to MXene dispersion is 8-10:10-11; and the ultrasonic oscillation time is 10-15 minutes.

7. The method for preparing a textile-based flexible temperature sensing interdigitated electrode as described in claim 1, characterized in that... In step (6): the volume ratio of AgNWs dispersion: MXene / AgNPs composite dispersion: temperature-responsive ionic liquid is 5-4:2-1.5:2-4; the temperature-responsive ionic liquid is at least one of 1-ethyl-3-methylimidazolium tetrafluoroborate, 1-ethyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide, 1-hexyl-2,3-dimethylimidazolium hexafluorophosphate, and 1,2-dimethyl-3-hydroxyethylimidazolium p-methylbenzenesulfonate; the strong yarn is polyester, nylon, or cotton yarn with a fineness of 200-600D; before or after plasma etching, the strong yarn is coated with polydopamine; the polydopamine coating treatment is specifically as follows: the yarn is placed in a Tris-HCl buffer solution with a pH of ≈8.5, dopamine hydrochloride is added to make its concentration 10-30 mg / L, and after standing for 18-48 hours, it is taken out and dried.

8. The method for preparing a textile-based flexible temperature sensing interdigitated electrode as described in claim 1, characterized in that... In step (7): the textile substrate is a knitted fabric, woven fabric or nonwoven fabric; the composite method is sewing, weaving or embroidery.

9. A textile-based flexible temperature sensing interdigital electrode, characterized in that... It is prepared by any one of claims 1 to 8.

10. The application of the textile-based flexible temperature sensing interdigitated electrode as described in claim 9 in the fabrication of artificial skin and wearable temperature sensing devices.

Images