Preparation method of high-sensitivity flexible pressure sensor based on microstructure design
By constructing microstructures on the surface of flexible sponge using template method and electrostatic self-assembly, and loading carbon nanotubes and graphene nanosheets, the problems of narrow detection range and easy damage of flexible pressure sensors are solved, realizing a sensor with high sensitivity and wide pressure working range, which is suitable for smart medical care and wearable health monitoring.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-12-23
- Publication Date
- 2026-03-27
AI Technical Summary
Existing flexible pressure sensors maintain high sensitivity but have a narrow detection range and their microstructures are easily damaged, leading to a decline in sensing performance. It is difficult to achieve both a wide detection range and high sensitivity.
A flexible sponge with a microstructured surface was constructed using a template method. A highly sensitive flexible sponge pressure sensor was prepared by loading carbon nanotubes and graphene nanosheets through electrostatic self-assembly. Stress concentration and conductive network reconstruction were achieved by utilizing the synergistic effect mechanism of microstructure-porous structure.
A flexible pressure sensor with high sensitivity and a wide pressure operating range has been developed, with a 7-fold increase in sensing sensitivity and a resistance as low as 3 kΩ. It can generate a highly sensitive electrical response to weak pressure signals and is suitable for smart medical equipment and high-precision wearable health monitors.
Smart Images
Figure CN121736366A_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of flexible electronic materials technology, specifically relating to a method for fabricating a highly sensitive flexible pressure sensor based on microstructure design. Background Technology
[0002] Flexible pressure sensors have shown broad application prospects in wearable electronics, health monitoring, and human-computer interaction. To improve sensor sensitivity, microstructure design has become a key strategy. Existing technologies typically employ templates with pyramidal, sandpaper-textured, or conical shapes to construct microstructures on the surface of an elastomer, aiming to reduce the detection limit and improve sensitivity by increasing local stress concentration. However, these surface microstructure-based sensors are limited by the finite compressive deformation capability of their microstructure layers, generally resulting in a narrow detection range. Furthermore, the microstructure itself is prone to irreversible plastic deformation or damage under repeated high stress, leading to performance degradation or even failure. Therefore, how to significantly broaden the sensor's detection range while maintaining high sensitivity has become a pressing technical challenge in this field.
[0003] Sensors based on three-dimensional porous sponges offer the potential for wide detection ranges due to their excellent intrinsic elasticity and repeatable compressibility. Existing technologies typically load conductive materials (such as carbon nanotubes and graphene) onto a sponge framework, sensing pressure by monitoring changes in resistance. While these devices exhibit good cycling stability and a wide measurement range, their sensitivity is generally low due to the lack of an effective stress concentration mechanism in ordinary sponges, making it difficult to effectively detect minute pressures. Therefore, constructing flexible pressure sensors with high sensitivity and a wide detection range is of great significance. To address these issues, this invention aims to provide a novel sensor solution. This solution constructs a sponge with a microstructure and optimizes the conductive layer bonding process to simultaneously achieve high sensitivity, a low detection limit, and a wide detection range. It is expected to be widely applied in fields such as intelligent medical equipment, intelligent sports equipment, and high-precision wearable health monitors. Summary of the Invention
[0004] The purpose of this invention is to provide a method for fabricating a highly sensitive flexible pressure sensor based on microstructure design. The method uses a template method to construct a flexible sponge with a microstructured surface, and then fabricates a highly sensitive flexible sponge pressure sensor through electrostatic self-assembly. This solves the problems of being unable to simultaneously achieve high sensitivity and a wide pressure working range in the fabrication of flexible sensors, as well as the complexity and poor quality of the fabrication process.
[0005] The technical solution of this invention is: A method for fabricating a highly sensitive flexible pressure sensor based on microstructure design, specifically including the following steps: (1) Preparation of PDMS microstructured sponge by template method The curing agent and polydimethylsiloxane (PDMS) were mixed and placed under mild vacuum conditions to remove air bubbles. Then, ground sodium citrate monohydrate and sodium chloride were added and stirred together. The mixture was transferred to a cubic mold and covered with sandpaper of different mesh sizes at the top and bottom ends. The mold was then cured in an oven. The sample was immersed in water to remove sodium citrate monohydrate and sodium chloride, and then dried for later use. (2) Preparation of ion-salting solution for loaded carbon nanotubes Carbon nanotubes were added to a dimethyl diallyl ammonium chloride solution, and then the prepared PDMS microstructured sponge was immersed in the carbon nanotube dimethyl diallyl ammonium chloride solution for a certain period of time, and then dried for later use. (3) Graphene nanosheets supported Graphene nanosheets were added to a sodium dodecylbenzenesulfonate solution, and then the prepared carbon nanotube PDMS microstructured sponge was immersed in the sodium dodecylbenzenesulfonate solution of graphene nanosheets for a certain period of time and dried to obtain a highly sensitive flexible sponge pressure sensor with microstructure design.
[0006] Further, the mass ratio of monohydrate and sodium citrate, sodium chloride and PDMS in step (1) is 1:1:1, 1:1:3, 1:1:5.
[0007] Furthermore, the sandpaper with different mesh sizes mentioned in step (1) is 100-600 mesh.
[0008] Furthermore, the curing temperature in the oven described in step (1) is 130°C.
[0009] Furthermore, the curing time in the oven in step (1) is 60 min.
[0010] Furthermore, the sample in step (1) is immersed in water for 120 min.
[0011] Further, in step (2), the mass concentration of carbon nanotubes in the dimethyl diallyl ammonium chloride solution is 1-5 mg / mL.
[0012] Furthermore, the immersion time in the dimethyl diallyl ammonium chloride solution of carbon nanotubes in step (2) is 4 hours.
[0013] Further, in step (3), the mass concentration of graphene nanosheets in the sodium dodecylbenzenesulfonate solution of graphene is 1-5 mg / mL.
[0014] Furthermore, the time for immersing the graphene in the sodium dodecylbenzenesulfonate solution in step (3) is 4 h.
[0015] The advantages of this invention are: (1) A flexible sponge with a microstructured surface was constructed by template method, and a high-sensitivity flexible sponge pressure sensor was prepared by electrostatic self-assembly. The prepared carbon nanotube / graphene nanosheet microstructured sponge has good mechanical flexibility and excellent sensing performance, which solves the problems of high sensitivity and wide pressure working range flexible sensor performance being difficult to balance and complex preparation process.
[0016] (2) Carbon nanotube / graphene nanosheet microstructured sponges possess excellent sensing sensitivity. The high sensitivity of sponge pressure sensors with microstructures on their surface is mainly due to their unique microstructure-porous structure synergistic mechanism. In the initial pressure stage, the protruding parts of the microstructure generate a significant stress concentration effect, transforming minute pressure into huge local deformation, thereby rapidly changing the conductive network composed of carbon nanotubes and graphene nanosheets near the contact point. Simultaneously, the contact area of these microstructures rapidly expands from a point to a surface as pressure increases, while the compression of the sponge matrix itself further amplifies the reconstruction and connection of the conductive pathways, collectively leading to a dramatic change in resistance with pressure. Therefore, it can produce a highly sensitive electrical response even to weak pressure signals. We used a template method to construct microstructure regions on the sponge surface and then quickly and easily prepared a flexible sponge pressure sensor with high sensitivity and a wide pressure sensor range through electrostatic self-assembly.
[0017] (3) The highly sensitive flexible sponge pressure sensor exhibits excellent conductivity, ultra-high sensitivity, and a wide range of pressure detection capabilities. The resistance of the fabricated flexible sponge pressure sensor is as low as 3 kΩ. The sensing sensitivity of the flexible sponge pressure sensor with microstructure design is increased by 7 times, reaching 23.87 kPa. -1 Furthermore, it can quickly and sensitively monitor a range of pressure deformations. This patent solves the problems of complex fabrication technology and poor pressure sensing performance of flexible pressure sensors, and can be widely used in fields such as intelligent medical equipment, intelligent sports equipment, and high-precision wearable health monitors. Attached Figure Description
[0018] 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. Figure 1 In Figure a, it is a schematic diagram of the sponge preparation based on microstructure design according to the present invention, and in Figure b, it is a schematic diagram of the preparation process of the high-sensitivity flexible sponge pressure sensor according to the present invention. Figure 2In Figures a and b, we see scanning electron microscope images at different magnifications of the original sponge used to prepare the highly sensitive flexible pressure sensor based on microstructure design in Example 4. Figure 3 In Example 4, image a is a scanning electron microscope (SEM) image of the highly sensitive flexible pressure sensor based on microstructure design after carbon nanotube modification, and image b is a scanning electron microscope (SEM) image of the highly sensitive flexible pressure sensor based on microstructure design after graphene nanosheet modification, prepared in Example 4. Figure 4 Optical images of different sodium citrate / sodium chloride and PDMS for the high-sensitivity flexible pressure sensor based on microstructure design prepared in Example 4, where a is a sponge sample with a mass ratio of monohydrate and sodium citrate, sodium chloride and PDMS of 1:1:1, and b is a sponge sample with a mass ratio of monohydrate and sodium citrate, sodium chloride and PDMS of 1:1:5.
[0019] Figure 5 The resistance variation trend of the high-sensitivity flexible pressure sensor based on microstructure design prepared in Example 4; Figure 6 The pressure sensing sensitivity curve of the high-sensitivity flexible pressure sensor based on microstructure design prepared in Example 4; Figure 7 In Example 4, ab represents pressure sensing attempts at different frequencies using the high-sensitivity flexible pressure sensor based on microstructure design prepared in Example 4; c represents pressure sensing attempts at different masses using the high-sensitivity flexible pressure sensor based on microstructure design prepared in Example 4; and d represents pressure sensing attempts at different pressures using the high-sensitivity flexible pressure sensor based on microstructure design prepared in Example 4. Detailed Implementation
[0020] This invention provides a method for fabricating a highly sensitive flexible pressure sensor based on microstructure design, comprising the following steps: (1) Preparation of PDMS microstructured sponge by template method (2) Loaded carbon nanotubes (3) Graphene nanosheets supported To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the present invention will be further described in detail below with reference to specific embodiments.
[0021] Step 1: Preparation of PDMS microstructured sponge using template method In one embodiment, this step can be specifically performed as follows: First, a PDMS substrate with a curing agent weight ratio of 10:1 is mixed in a petri dish and placed under mild vacuum conditions to remove air bubbles. Then, ground sodium citrate monohydrate, sodium chloride, and PDMS are stirred together for 10 min, with mass ratios of sodium citrate monohydrate, sodium chloride, and PDMS of 1:1:1, 1:1:3, and 1:1:5. The mixture is transferred to a cubic mold and covered with sandpaper of 100-600 mesh at both ends. After curing at 130°C for 60 min, the sample is immersed in water to remove sodium citrate monohydrate and sodium chloride, and then dried in an oven at 60°C.
[0022] Step 2: Loading carbon nanotubes In one embodiment, this step can be specifically performed as follows: prepare a 5 wt% dimethyl diallyl ammonium chloride solution, add carbon nanotubes with a final concentration of 1-5 mg / mL, then immerse the prepared PDMS microstructured sponge in the carbon nanotube dimethyl diallyl ammonium chloride solution for 4 h, and dry it for later use.
[0023] Step 3: Loading graphene nanosheets In one embodiment, this step can be specifically performed as follows: prepare a 5 wt% sodium dodecylbenzenesulfonate solution, add graphene nanosheets with a final concentration of 1-5 mg / mL, then immerse the prepared carbon nanotube PDMS microstructured sponge in the graphene sodium dodecylbenzenesulfonate solution for 4 h, and dry it to obtain a highly sensitive flexible sponge pressure sensor with microstructure design.
[0024] To make the above-mentioned objects, features, and advantages of the present invention more apparent and understandable, the technical solutions of the present invention will be further described below in conjunction with the accompanying drawings and embodiments. However, the present invention is not limited to the listed embodiments, but should also include any other known modifications within the scope of the claims of the present invention.
[0025] First, 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 throughout 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.
[0026] Secondly, this invention is described in detail using structural diagrams, etc. When detailing the embodiments of this invention, for ease of explanation, the diagrams may be partially enlarged, deviating from the general scale. Furthermore, the diagrams are merely examples and should not limit the scope of protection of this invention. In addition, actual manufacturing should include three-dimensional space with length, width, and depth.
[0027] Example 1 This embodiment prepares a highly sensitive flexible pressure sensor based on microstructure design according to the following steps: Step 1: Preparation of PDMS microstructured sponge using template method First, PDMS substrate with a curing agent weight ratio of 10:1 was mixed in a petri dish and placed under mild vacuum conditions to remove air bubbles. Then, ground sodium citrate monohydrate, sodium chloride, and PDMS were added and stirred for 10 min. The mass ratio of sodium citrate monohydrate to sodium chloride and PDMS was 1:1:1. The mixture was transferred to a cubic mold and covered with 200-mesh sandpaper at both ends. After curing at 130°C for 60 min, the sample was immersed in water to remove sodium citrate monohydrate and sodium chloride, and then dried in a 60°C oven.
[0028] Step 2: Loading carbon nanotubes Prepare a 5 wt% dimethyl diallyl ammonium chloride solution, add carbon nanotubes to a final concentration of 1 mg / mL, then immerse the prepared PDMS microstructured sponge in 20 mL of the carbon nanotube dimethyl diallyl ammonium chloride solution for 4 h, and dry it for later use.
[0029] Step 3: Loading graphene nanosheets A 5 wt% sodium dodecylbenzenesulfonate solution was prepared, and graphene nanosheets with a final concentration of 1 mg / mL were added. The prepared carbon nanotube PDMS microstructured sponge was then immersed in 20 mL of the graphene sodium dodecylbenzenesulfonate solution for 4 h.
[0030] Example 2 This embodiment prepares a highly sensitive flexible pressure sensor based on microstructure design according to the following steps: Step 1: Preparation of PDMS microstructured sponge using template method First, PDMS substrate with a curing agent weight ratio of 10:1 was mixed in a petri dish and placed under mild vacuum conditions to remove air bubbles. Then, ground sodium citrate monohydrate, sodium chloride, and PDMS were added and stirred for 10 min. The mass ratio of sodium citrate monohydrate to sodium chloride and PDMS was 1:1:5. The mixture was transferred to a cubic mold and covered with 200-mesh sandpaper at both ends. After curing at 130°C for 60 min, the sample was immersed in water to remove sodium citrate monohydrate and sodium chloride, and then dried in a 60°C oven.
[0031] Step 2: Loading carbon nanotubes Prepare a 5 wt% dimethyl diallyl ammonium chloride solution, add carbon nanotubes to a final concentration of 2 mg / mL, then immerse the prepared PDMS microstructured sponge in 20 mL of the carbon nanotube dimethyl diallyl ammonium chloride solution for 4 h, and dry it for later use.
[0032] Step 3: Loading graphene nanosheets A 5 wt% sodium dodecylbenzenesulfonate solution was prepared, and graphene nanosheets with a final concentration of 2 mg / mL were added. Subsequently, the prepared carbon nanotube PDMS microstructured sponge was immersed in 20 mL of the graphene sodium dodecylbenzenesulfonate solution for 4 h.
[0033] Example 3 This embodiment prepares a highly sensitive flexible pressure sensor based on microstructure design according to the following steps: Step 1: Preparation of PDMS microstructured sponge using template method First, PDMS substrate with a curing agent weight ratio of 10:1 was mixed in a petri dish and placed under mild vacuum conditions to remove air bubbles. Then, ground sodium citrate monohydrate, sodium chloride, and PDMS were added and stirred for 10 min. The mass ratio of sodium citrate monohydrate to sodium chloride and PDMS was 1:1:3. The mixture was transferred to a cubic mold and covered with 130-mesh sandpaper at both ends. After curing at 130°C for 60 min, the sample was immersed in water to remove sodium citrate monohydrate and sodium chloride, and then dried in a 60°C oven.
[0034] Step 2: Loading carbon nanotubes Prepare a 5 wt% dimethyl diallyl ammonium chloride solution, add carbon nanotubes to a final concentration of 4 mg / mL, then immerse the prepared PDMS microstructured sponge in 20 mL of the carbon nanotube dimethyl diallyl ammonium chloride solution for 4 h, and dry it for later use.
[0035] Step 3: Loading graphene nanosheets A 5 wt% sodium dodecylbenzenesulfonate solution was prepared, and graphene nanosheets with a final concentration of 4 mg / mL were added. Subsequently, the prepared carbon nanotube PDMS microstructured sponge was immersed in 20 mL of the graphene sodium dodecylbenzenesulfonate solution for 4 h.
[0036] Example 4 This embodiment prepares a highly sensitive flexible pressure sensor based on microstructure design according to the following steps: Step 1: Preparation of PDMS microstructured sponge using template method First, PDMS substrate with a curing agent weight ratio of 10:1 was mixed in a petri dish and placed under mild vacuum conditions to remove air bubbles. Then, ground sodium citrate monohydrate, sodium chloride, and PDMS were added and stirred for 10 min. The mass ratio of sodium citrate monohydrate to sodium chloride and PDMS was 1:1:5. The mixture was transferred to a cubic mold and covered with 130-mesh sandpaper at both ends. After curing at 130°C for 60 min, the sample was immersed in water to remove sodium citrate monohydrate and sodium chloride, and then dried in a 60°C oven.
[0037] Step 2: Loading carbon nanotubes Prepare a 5 wt% dimethyl diallyl ammonium chloride solution, add carbon nanotubes to a final concentration of 4 mg / mL, then immerse the prepared PDMS microstructured sponge in 20 mL of the carbon nanotube dimethyl diallyl ammonium chloride solution for 4 h, and dry it for later use.
[0038] Step 3: Loading graphene nanosheets A 5 wt% sodium dodecylbenzenesulfonate solution was prepared, and graphene nanosheets with a final concentration of 5 mg / mL were added. Subsequently, the prepared carbon nanotube PDMS microstructured sponge was immersed in 20 mL of the graphene sodium dodecylbenzenesulfonate solution for 4 h.
[0039] Please see Figure 1 , Figure 1 This is a schematic diagram illustrating the fabrication process of the high-sensitivity flexible pressure sensor based on microstructure design according to the present invention. Figure 1 As shown, sandpaper was first used as a rough template, and pores were created in PDMS using a salt solution. Carbon nanotubes and graphene nanosheets were then bonded to the PDMS sponge framework using an electrostatic self-assembly method to obtain a carbon nanotube / graphene nanosheet microstructured sponge.
[0040] Please see Figure 2 , Figure 2 This is a scanning electron microscope (SEM) image of the original sponge used in the high-sensitivity flexible pressure sensor based on microstructure design prepared in Embodiment 4 of the present invention. After being treated with sandpaper, the sponge surface exhibits an uneven and rough surface morphology.
[0041] Please see Figure 3 , Figure 3 This is a scanning electron microscope (SEM) image of the conductive modification of the highly sensitive flexible pressure sensor based on microstructure design prepared in Embodiment 4 of the present invention. Figure 3 As shown, carbon nanotubes / graphene nanosheets were successfully loaded onto a microstructured sponge.
[0042] Please see Figure 4 , Figure 4This is an optical image of the highly sensitive flexible pressure sensor based on microstructure design prepared in Embodiment 4 of the present invention. Figure 4 As shown, the carbon nanotube / graphene nanosheet microstructured sponge we prepared has excellent compression resilience.
[0043] Please see Figure 5 , Figure 5 This is a resistance variation trend graph of the highly sensitive flexible pressure sensor based on microstructure design prepared in Embodiment 4 of the present invention. Figure 5 As shown, after treatment with carbon nanotubes and graphene sheets, the resistance of the carbon nanotube / graphene nanosheet microstructured sponge decreased to 3 kΩ.
[0044] Please see Figure 6 , Figure 6 This is a pressure sensing sensitivity curve of the highly sensitive flexible pressure sensor based on microstructure design prepared in Embodiment 4 of the present invention. Figure 6 As shown, this flexible pressure sensor exhibits a wide range of highly sensitive pressure sensing characteristics.
[0045] Please see Figure 7 , Figure 7 This is a pressure sensing attempt of the high-sensitivity flexible pressure sensor based on microstructure design prepared in Embodiment 4 of the present invention. For example... Figure 7 As shown, the flexible pressure sensor can quickly detect pressure at different weights.
[0046] like Figure 4 As shown, when the mass ratio is 1:1:1, the prepared sponge exhibits low porosity, poor elasticity, and cannot be compressed by hand. Increasing the ratio from 1:1:1 to 1:1:5, the prepared sponge gradually becomes softer, demonstrating excellent elasticity and being fully compressible. When the ratio continues to increase, the PDMS solution cannot encapsulate sodium citrate monohydrate and sodium chloride, failing to form a PDMS sponge with a porous structure. Therefore, the optimal ratio is determined to be 1:1:5. Using this ratio to prepare PDMS sponges not only introduces microstructures onto the sponge surface but also reduces preparation time and accelerates the preparation process.
[0047] Figure 5 It can be seen that after the PDMS sponge is first immersed in a carbon nanotube solution, the resistance drops to 6 MΩ. After drying, it is immersed in a negatively charged graphene nanosheet solution, and the resistance drops further to 3 KΩ. When it is immersed in a carbon nanotube solution again, the resistance remains basically unchanged, indicating that the carbon nanotubes and graphene nanosheets have reached the adsorption saturation state in the sponge skeleton.
[0048] The sponge prepared in Example 4 exhibits optimal mechanical properties and best resilience during practical use. Furthermore, it demonstrates optimal resistance with increasing concentration of the conductive solution, representing the best experimental conditions. Our prepared flexible sponge pressure sensor possesses high sensing sensitivity, ultra-low pressure detection line, and a wide pressure operating range, and is expected to find widespread application in fields such as intelligent medical equipment, intelligent sports equipment, and high-precision wearable health monitors.
[0049] In the four embodiments above, a sponge with surface microstructures was constructed using a template method, and a highly sensitive flexible sponge pressure sensor was prepared through electrostatic self-assembly, exhibiting excellent pressure sensing capabilities. Please refer to [link to previous document]. Figure 7 , Figure 7 This invention presents a pressure sensing attempt for a highly sensitive flexible pressure sensor based on microstructure design. For example... Figure 7 As shown, this flexible pressure sensor can quickly and sensitively monitor different pressure deformations in a timely manner.
[0050] In summary, this invention discloses a method for fabricating a highly sensitive flexible pressure sensor based on microstructure design. Building upon existing technologies, this method employs a template method to construct a flexible sponge with a microstructured surface, and then fabricates a highly sensitive flexible sponge pressure sensor through electrostatic self-assembly, resulting in a flexible sponge pressure sensor with high sensitivity and a wide working pressure range. The reaction conditions are mild, the process is simple and easy to operate, and it exhibits high sensing sensitivity and a wide working pressure window.
[0051] 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 claims of the present invention.
Claims
1. A method for fabricating a highly sensitive flexible pressure sensor based on microstructure design, characterized in that, Includes the following steps: (1) Mix the curing agent and polydimethylsiloxane PDMS and place it under mild vacuum conditions to remove air bubbles; then add sodium citrate monohydrate and sodium chloride and stir together. Transfer the mixture to a cubic mold and cover the top and bottom ends with sandpaper before curing in an oven. Immerse the sample in water to remove sodium citrate monohydrate and sodium chloride, and then dry it. (2) Weigh a certain amount of carbon nanotubes and add them to a dimethyl diallyl ammonium chloride solution. Then, immerse the PDMS microstructured sponge prepared in step (1) into the dimethyl diallyl ammonium chloride solution of carbon nanotubes, and dry it for later use. (3) Weigh a certain amount of graphene nanosheets and add them to a sodium dodecylbenzene sulfonate solution. Then, immerse the carbon nanotube PDMS microstructure sponge prepared in step (2) into the sodium dodecylbenzene sulfonate solution of graphene and dry it to obtain the high-sensitivity flexible pressure sensor based on microstructure design.
2. The method for fabricating a highly sensitive flexible pressure sensor based on microstructure design according to claim 1, characterized in that: The mass ratios of monohydrate, sodium citrate, sodium chloride, and PDMS are 1:1:1, 1:1:3, and 1:1:
5.
3. The method for fabricating a highly sensitive flexible pressure sensor based on microstructure design according to claim 1, characterized in that: The sandpaper has a mesh size of 100-600.
4. The method for fabricating a highly sensitive flexible pressure sensor based on microstructure design according to claim 1, characterized in that: The curing temperature of the oven is 130℃.
5. The method for fabricating a highly sensitive flexible pressure sensor based on microstructure design according to claim 1, characterized in that: The curing time in the oven is 60 minutes.
6. The method for fabricating a highly sensitive flexible pressure sensor based on microstructure design according to claim 1, characterized in that: The sample was immersed in water for 120 minutes.
7. The method for fabricating a highly sensitive flexible pressure sensor based on microstructure design according to claim 1, characterized in that: In step (2), the mass concentration of carbon nanotubes in the dimethyl diallyl ammonium chloride solution is 1-5 mg / mL.
8. The method for fabricating a highly sensitive flexible pressure sensor based on microstructure design according to claim 1, characterized in that: The immersion time in the carbon nanotubes in the dimethyl diallyl ammonium chloride solution was 4 h.
9. The method for fabricating a highly sensitive flexible pressure sensor based on microstructure design according to claim 1, characterized in that: In step (3), the mass concentration of graphene nanosheets in the sodium dodecylbenzenesulfonate solution is 1-5 mg / mL.
10. The method for fabricating a highly sensitive flexible pressure sensor based on microstructure design according to claim 1, characterized in that: The immersion time in the sodium dodecylbenzenesulfonate solution of graphene was 4 h.