Triboelectric sensor with high-durability nano sensing coating as well as preparation method and application of triboelectric sensor

Abstract

The invention discloses a triboelectric sensor with a high-durability nano sensing coating and a preparation method and application thereof, and belongs to the technical field of sensors, the triboelectric sensor comprises an electrode and a friction layer, and the friction layer comprises a high-durability aminated oleophobic nano coating. The invention also discloses an application of the triboelectric sensor in detection of acidified pollutants in lubricating oil, and also discloses an integrated signal collection, processing and transmission sensor system. According to the invention, the service life of the sensor for detection in the lubricating oil is prolonged, the maintenance cost is reduced, the real-time monitoring of the state data of the lubricating oil is realized, the automation level of monitoring is improved, and the intelligent analysis of acidic pollutants in the lubricating oil and the intelligent control of the system are realized.

Description

Technical Field

[0001] The present invention belongs to the technical field of sensors, and particularly relates to a triboelectric sensor with a highly durable nano-sensing coating, a preparation method thereof, and an application thereof. Background Art

[0002] In modern industry, as a key medium for equipment operation, the state of lubricating oil directly affects the stability and lifespan of equipment. Acidified pollutants in lubricating oil, such as aged oil, are direct indicators of aging degree and external pollution. Acidic substances in lubricating oil can corrode metal components, accelerate wear, reduce the equipment lifespan, and may also form precipitates, affecting the fluidity and heat dissipation performance of the oil. Therefore, it is particularly important to provide a sensor that can accurately monitor acidified pollutants.

[0003] The detection of acidic substances in oil mainly uses electrochemical probes for measurement. By using specific electrodes, the concentration of specific ions in the solution can be selectively responded to, thereby measuring the composition and concentration of acidic substances in the oil. The conductivity, capacitance, and impedance of the oil will also change with the increase of acidic substances in the oil, and the sensor can also detect the corresponding information. However, traditional detection methods have problems such as insufficient accuracy, inability to monitor in real time, susceptibility to interference from other substances in the oil, and low intelligence level, which limit the monitoring efficiency and accuracy.

[0004] Compared with traditional oil monitoring sensors, triboelectric sensors have the advantages of low manufacturing cost and high sensitivity, and can also be used as self-powered sensors, which also have advantages in solving the power supply problem of intelligent sensors.

[0005] Therefore, how to provide a method for detecting acidic substances in oil using triboelectric sensors is a technical problem that needs to be urgently solved by those skilled in the art. Summary of the Invention

[0006] To solve the above technical problems, the present invention proposes a triboelectric sensor with a highly durable nano-sensing coating, a preparation method thereof, and an application thereof.

[0007] To achieve the above object, the present invention provides the following technical solutions:

[0008] A triboelectric sensor with a highly durable nano-sensing coating, comprising an electrode and a friction layer, and the friction layer includes a self-healing and self-repairing amino-functionalized oil-repellent nano-coating.

[0009] Preferably, the electrode includes one or several of gold, silver, aluminum, copper, titanium, chromium, selenium, iron, manganese, platinum, nickel, palladium, copper alloy, and aluminum alloy. The above metals have good electrical conductivity and can efficiently conduct current.

[0010] Preferably, the material of the friction layer includes one or more of polydimethylsiloxane, polyethylene, polypropylene, polyvinylidene fluoride, ethylene propylene fluoride, vinylidene chloride acrylonitrile copolymer, polytetrafluoroethylene, polyvinyl chloride, chlorotrifluoroethylene, chloroprene rubber, polyisobutylene, polyoxymethylene, polyamide, and polyimide. The above polymers have good triboelectric properties, can generate a large amount of charges during the contact and separation with the electrode, thereby improving the output power of the nanogenerator, and have good flexibility and wear resistance, and are also convenient to be processed into different shapes.

[0011] Preferably, the shapes of the friction layer and the electrode include but are not limited to sheet shape, tube shape, and ring shape. Different shapes can be applied to different environments and are convenient for installation.

[0012] Preferably, the types of the triboelectric sensors include but are not limited to single-electrode form and double-electrode form.

[0013] Preferably, the preparation method of the highly durable amino-functionalized superoleophobic nanocoating includes the following steps:

[0014] Modifying nanoparticles with a compound containing a disulfide bond, then dispersing the obtained modified nanoparticles in water, adding an anionic fluorocarbon surfactant, mixing at room temperature for 60 - 80 min to form a mixed solution, spraying the mixed solution on the surface of the friction layer and then drying, repeating the spraying and drying steps, repeating this step 4 - 6 times to obtain a superoleophobic coating, and finally modifying the superoleophobic coating with a modifier to obtain the highly durable amino-functionalized superoleophobic nanocoating.

[0015] Preferably, the nanoparticles include one or more of silica nanoparticles, titanium dioxide particles, polystyrene nanoparticles, and carbon nanotubes;

[0016] The particle size of the nanoparticles is 20 - 80 nm, and the modification ratio of the compound containing a disulfide bond to the nanoparticles is 1:(10 - 20).

[0017] Preferably, the mass ratio of the modified nanoparticles to water is 1:(30 - 50).

[0018] The mass ratio of the anionic fluorocarbon surfactant to the nanoparticles is (10 - 20):1;

[0019] The compound containing a disulfide bond includes but is not limited to at least one of 4,4'-diaminodiphenyl disulfide, 2,2'-diaminodiphenyl disulfide, 5,5'-dithiobis(2-nitrobenzoic acid), diallyl trisulfide, dimethyl disulfide, dithiophene, lipoic acid, and amino acids. The introduction of disulfide bonds in the present invention can improve the durability and stability of the material.

[0020] Preferably, the amino-containing modifier includes an amino-silane coupling agent.

[0021] More preferably, the amino-silane coupling agent includes one or more of γ-aminopropyltriethoxysilane, γ-glycidoxypropyltrimethoxysilane, N-β(aminoethyl)-γ-aminopropyltrimethoxysilane, N-β(aminoethyl)-γ-aminopropylmethyldimethoxysilane, phenylaminomethyltriethoxysilane, and phenylaminomethyltrimethoxysilane. In the present invention, the introduction of amino groups can be used to detect acidified pollutants and has a more sensitive response to acidified substances.

[0022] Preferably, the surface roughness of the superoleophobic coating is 3 - 10 μm.

[0023] Preferably, the temperature of the modification treatment is normal temperature (20°C - 25°C), and the time is 30 - 40 min.

[0024] Preferably, the mass ratio of the nanoparticles to the modifier is 1:(0.001 - 0.05).

[0025] An application of the above-mentioned triboelectric sensor in detecting acidified pollutants in lubricating oil.

[0026] An integrated signal collection, processing, and transmission sensor system, comprising:

[0027] The above-mentioned triboelectric sensor, a microprogram control unit, and a transmitter / receiver unit;

[0028] Wherein, the triboelectric sensor is electrically connected to the microprogram control unit;

[0029] The microprogram control unit is connected to the transmitter / receiver unit by wireless transmission.

[0030] Preferably, the microprogram control unit adopts an embedded processor including but not limited to STM32, MSP430, NVIDIA Jetson Xavier, Jetson Nano, etc.

[0031] The wireless transmission includes but not limited to Bluetooth transmission, Wi-Fi network connection transmission, 4G / 5G transmission, etc.

[0032] More preferably, the transmitter / receiver unit includes a deep learning model, and a dataset between the output voltage of the triboelectric sensor and the lubricating oil contamination is established through preliminary experiments;

[0033] Train a deep learning model and directly input the wireless transmission data of the triboelectric sensor into the model;

[0034] The data set includes, but is not limited to, an output input signal image data set, a voltage current signal data set, and an experimental picture data set;

[0035] The deep learning model includes, but is not limited to, an artificial neural network, a convolutional neural network, a recurrent neural network, or a long short-term memory network.

[0036] A method for monitoring acid pollutants in lubricating oil, using the integrated signal collection, processing, and transmission sensor system described in claim 8.

[0037] Preferably, it includes the following steps:

[0038] The microprogram control unit receives the voltage signal generated by the triboelectric sensor and processes it, analyzes the voltage signal to determine the content of acid pollutants in the lubricating oil, and then uses the transmitter / receiver unit to wirelessly transmit the analyzed data to the remote monitoring platform. When the content of acid pollutants exceeds the preset threshold, the remote monitoring platform issues a warning signal through the alarm system.

[0039] Compared with the prior art, the present invention has the following advantages and technical effects:

[0040] Based on the self-healing and oil-repellent characteristics of the contact surface of the triboelectric sensor, the present invention extends the service life of the sensor for detecting in lubricating oil, reduces the maintenance cost. Through the embedding of the acid-responsive coating, the triboelectric sensor can achieve highly selective monitoring of acid pollutants in lubricating oil. The construction of the integrated signal collection, processing, and transmission sensor system realizes real-time monitoring of the data of the lubricating oil state and improves the automation level of monitoring. The present invention also proposes an intelligent monitoring method for acid pollutants in lubricating oil, using a deep learning model to analyze signal data to achieve intelligent analysis of acid pollutants in lubricating oil and intelligent control of the system. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] The drawings constituting a part of this application are used to provide a further understanding of this application. The schematic embodiments of this application and their descriptions are used to explain this application and do not constitute an improper limitation to this application. In the drawings:

[0042] Figure 1 It is a schematic diagram of the surface of the triboelectric sensor with a highly durable nano-sensing coating in the present invention;

[0043] Figure 2 It is a schematic diagram of the structure of the triboelectric sensor in Embodiment 1;

[0044] Among them, the reference numerals are: polytetrafluoroethylene sheet 1, sheet-shaped copper electrode 2;

[0045] Figure 3 It is a schematic diagram of the structure of the triboelectric sensor in Embodiment 2;

[0046] Among them, the labels are: polyimide tubular structure 1 and sheet-like aluminum electrode 2;

[0047] Figure 4 It is the voltage output result diagram of the triboelectric sensor embedded with the highly durable nano-sensing coating obtained in Example 1 of the present invention;

[0048] Among them, (a) is the voltage output result diagram without acidic pollutants, and (b) is the voltage output result diagram with 30% concentration acidic pollutants;

[0049] Figure 5 It is the durability result of the triboelectric sensor obtained in Example 1 of the present invention;

[0050] Figure 6 It is the working flow chart of the lubricating oil acidification pollutant detection sensor system of the present invention. Specific Embodiments

[0051] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0052] To make the above objects, features, and advantages of the present invention more obvious and understandable, the present invention will be further described in detail below in conjunction with the accompanying drawings and specific embodiments.

[0053] Unless otherwise specified, the raw materials in the embodiments of the present invention are all obtained through commercial channels;

[0054] Unless otherwise specified, the room temperature or normal temperature in the embodiments of the present invention refers to 20 - 25 °C.

[0055] It should be noted that the technologies not detailed in the embodiments of the present invention are all well-known conventional technical means in the art, which are not the key points of the invention and will not be elaborated.

[0056] Example 1

[0057] A preparation method of a lubricating oil acidification pollutant monitoring sensor with high durability characteristics based on a triboelectric sensor, comprising the following steps:

[0058] 1. Prepare a highly durable nano-sensor:

[0059] (1-1) Developing a wear-resistant superoleophobic coating on the surface of the friction layer of a triboelectric sensor: Modifying nanoparticles (4,4-diaminodiphenyl disulfide-modified silica nanoparticles with a particle size of 40 nm and a modification ratio of 1:10), an anionic fluorocarbon surfactant, and water are mixed at a mass ratio of 1:15:30 at room temperature for 60 min to obtain a mixed solution, which is then sprayed on the surface of the friction layer and dried in air. The spraying and drying are repeated 5 times to form a superoleophobic coating with an average surface roughness of 6 μm, resulting in a triboelectric sensor with a superoleophobic coating;

[0060] (1-2) Preparing a modifier solution by mixing γ-aminopropyltriethoxysilane and acetone solution at a ratio of 1:1 g. Then, at 20 °C, the above modifier solution is sprayed on the superoleophobic coating obtained in step (1), and the spraying, drying, and modification treatment are carried out for 30 minutes and repeated three times. Among them, the mass ratio of the modified nanoparticles to the modifier is 1:0.01, and finally, a sensing coating for detecting acidified pollutants is formed, resulting in a triboelectric sensor with a highly durable nanosensing coating. The structural schematic diagram is as Figure 1 shown.

[0061] 2. The designed triboelectric sensor realizes the monitoring of acidified pollutants in lubricating oil:

[0062] The triboelectric sensor includes a laminated polytetrafluoroethylene sheet 1 and a sheet-shaped copper electrode 2, and the structure is as Figure 2 shown. One end of the electrode is grounded to form a triboelectric sensor, which generates a voltage signal based on the principle of triboelectrification and electrostatic induction. The triboelectric sensor with a highly durable nanosensing coating obtained in step (1-2) is embedded to form a triboelectric sensor for detecting acidified pollutants in lubricating oil. The open-circuit voltage signals of the triboelectric sensor are measured under different acidified pollutant contents (no acidic pollutant (a) and 30% concentration acidic pollutant (b)), and the results are as Figure 4 shown. It can be seen that as the content of acidified pollutants increases, the voltage output signal decreases, and the triboelectric sensor can monitor when acidified pollutants first appear in the oil. The durability results are as Figure 5 shown. It can be seen that the triboelectric sensor obtained in this embodiment can maintain good stability.

[0063] The specific principle is as follows: During the operation of the triboelectric sensor, the copper electrode is partially submerged when the oil rises. According to the electron transfer theory, bound charges are formed between the surface of polytetrafluoroethylene and the oil due to the triboelectric effect. Due to the asymmetric distribution of charges, free electrons between the electrode and the grounded end transfer, flowing from the grounded end to the electrode until the surface is completely submerged by the oil. On the contrary, when the oil level drops, the potential distribution changes, and electrons flow from the electrode end to the grounded end. When the triboelectric sensor with an acidic substance-responsive coating is exposed to fresh alkaline lubricating oil, the amino group cannot be protonated and maintains its contracted configuration. When the triboelectric sensor comes into contact with aged oil, the amino group in the aged oil is protonated, and the surface of the triboelectric sensor becomes lipophilic. Therefore, as the degree of acidification increases, the sensor gradually produces a lower output signal;

[0064] 3. Build a sensor system that integrates signal acquisition, processing, and transmission:

[0065] The sensor system that integrates signal acquisition, processing, and transmission consists of the triboelectric sensor with a highly durable nano-sensing coating obtained in step 1, a microprogram control unit, and a transmitter / receiver unit;

[0066] Among them, the microprogram control unit uses a low-power MSP430 single-chip microcomputer to extend the operating life of the system. The wireless transmission method uses 5G communication technology to increase the transmission efficiency and accuracy;

[0067] The principle is that the triboelectric sensor wirelessly transmits the generated voltage signal to the microprogram control unit and transmits it to the user's computer terminal (user side) through the transmitter for display, and the user can control the sensing system.

[0068] 4. Identify the lubricating oil status signal through deep learning methods:

[0069] (4-1) Understand the voltage output of the acidic pollutant content under each working condition through pre-tests;

[0070] (4-2) Build a real-time status model of lubricating oil based on a convolutional neural network and establish a dataset on the relationship between the voltage signal of the triboelectric sensor and lubricating oil pollution. The wireless transmission data of the triboelectric sensor will be directly input into the convolutional neural network model (deep learning model) through the user side without complex data processing;

[0071] (4-3) According to the current voltage or component change trend, combined with the trained convolutional neural network model, give an early warning of the status of acidification pollutants in the lubricating oil. When the model identifies that the pollutant concentration exceeds the threshold, the alarm system is automatically activated, and the staff will maintain the machine and replace the new lubricating oil. The overall system working process is as Figure 6 shown.

[0072] Example 2

[0073] A preparation method of a lubricating oil acidification pollutant monitoring sensor with high durability characteristics based on a triboelectric sensor, comprising the following steps:

[0074] 1. Prepare a high-durability nanosensor:

[0075] (1-1) Develop an abrasion-resistant superoleophobic coating on the friction layer surface of the triboelectric sensor: Modify the nanoparticles (4,4-diaminodiphenyl disulfide-modified silica nanoparticles with a particle size of 50 nm and a modification ratio of 1:10), anionic fluorocarbon surfactant and water are mixed at a mass ratio of 1:15:35 at room temperature for 80 min to obtain a mixed solution, then sprayed on the friction layer surface and dried in air. Spray and dry 5 times to form a superoleophobic coating with an average surface roughness of 5 μm, obtaining a triboelectric sensor with a superoleophobic coating;

[0076] (1-2) Prepare a modifier solution by mixing γ-aminopropyltriethoxysilane and acetone solution at 1:1 g. Spray the above modifier solution on the superoleophobic coating obtained in step (1) at 20 °C and perform repeated spraying and drying modification treatment for 30 minutes three times. Among them, the mass ratio of the modified nanoparticles to the modifier is 1:0.01, and finally a sensing coating is formed, obtaining a triboelectric sensor with a high-durability nanosensing coating. The structural schematic diagram is as Figure 1 shown.

[0077] 2. Design the triboelectric sensor to realize the monitoring of acidification pollutants in lubricating oil:

[0078] The triboelectric sensor includes a laminated polyimide tubular structure 1 and a sheet-like aluminum electrode 2, and the structure is as Figure 3 shown. One end of the electrode is grounded to form a triboelectric sensor. Based on the principle of triboelectrification and electrostatic induction, a voltage signal is generated. Respectively embed the triboelectric sensor with a high-durability nanosensing coating obtained in step (1-2) and the triboelectric sensor with a superoleophobic coating obtained in step (1-1) to form a triboelectric sensor for detecting acidification pollutants in lubricating oil, and measure the open-circuit voltage signal of the triboelectric sensor under different acidification pollutant contents. As the acidification pollutant content increases, the voltage output signal decreases, and the triboelectric sensor can monitor when acidification pollutants first appear in the oil.

[0079] The principle is the same as that of Example 1. Specifically, during the operation of the triboelectric sensor, the aluminum electrode is partially submerged when the oil level rises. According to the electron transfer theory, bound charges are formed between the surface of the polyimide and the oil due to the triboelectric effect. Due to the asymmetric distribution of charges, free electrons between the electrode and the ground terminal transfer, flowing from the ground terminal to the electrode until the surface is completely submerged by the oil. On the contrary, when the oil level drops, the potential distribution changes, and electrons flow from the electrode terminal to the ground terminal. When the triboelectric sensor with an acidic substance-responsive coating is exposed to fresh alkaline lubricating oil, the amino group cannot be protonated and maintains its contracted configuration. When the triboelectric sensor comes into contact with aged oil, the amino group in the aged oil is protonated, and the surface of the triboelectric sensor becomes lipophilic. Therefore, as the degree of acidification increases, the sensor will gradually produce a lower output signal;

[0080] 3. Build a sensor system integrating signal acquisition, processing, and transmission:

[0081] The sensor system integrating signal acquisition, processing, and transmission consists of the triboelectric sensor with a highly durable nano-sensing coating obtained in Step 1, a microprogram control unit, and a transmitter / receiver unit;

[0082] Among them, the microprogram control unit uses a low-power MSP430 single-chip microcomputer to extend the system operation life, and the wireless transmission method (transmitter / receiver unit) uses a Wi-Fi network connection for transmission to increase the transmission efficiency and accuracy;

[0083] The principle is that the triboelectric sensor wirelessly transmits the generated voltage signal to the microprogram control unit and transmits it to the user computer terminal (user side) through the transmitter for display, and the user can control the sensing system.

[0084] 4. Identify the lubricating oil status signal through deep learning methods:

[0085] (4-1) Through pre-tests, understand the voltage output of the acidic pollutant content under various working conditions;

[0086] (4-2) Build a real-time status model of lubricating oil based on an artificial neural network, and establish a dataset on the relationship between the voltage signal of the triboelectric sensor and lubricating oil pollution. The wireless transmission data of the triboelectric sensor will be directly input into the training artificial neural network model (deep learning model) through the user side, without complex data processing;

[0087] (4-3) According to the current voltage or component change trend, combined with the trained artificial neural network model, give an early warning of the status of acidic pollutants in the lubricating oil. When the model identifies that the pollutant concentration exceeds the threshold, the alarm system is automatically activated, and the staff will maintain the machine and replace the new lubricating oil. The overall system workflow is as Figure 6as shown

[0088] The above is only a preferred specific embodiment of the present application, but the protection scope of the present application is not limited thereto. Any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present application should be covered by the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the protection scope of the claims.

Claims

1. A triboelectric sensor with a highly durable nano-sensing coating, comprising an electrode and a friction layer, characterized in that, The friction layer is coated with a highly durable amino-functionalized oleophobic nano-coating.

2. The triboelectric sensor with a highly durable nano-sensing coating according to claim 1, characterized in that The preparation method of the highly durable amino-functionalized oleophobic nano-coating includes the following steps: Modifying nanoparticles with a compound containing a disulfide bond, then dispersing the obtained modified nanoparticles in water, adding an anionic fluorocarbon surfactant, spraying the obtained mixed solution on the surface of the friction layer and drying, repeating the spraying and drying steps to obtain a super-oleophobic coating, and finally modifying the super-oleophobic coating with a modifier containing an amino group to obtain the highly durable amino-functionalized oleophobic nano-coating.

3. The triboelectric sensor with a highly durable nano-sensing coating according to claim 1, characterized in that, The nanoparticles are selected from one or more of silicon dioxide nanoparticles, titanium dioxide particles, polystyrene nanoparticles, and carbon nanotubes.

4. The triboelectric sensor with a highly durable nano-sensing coating according to claim 1, characterized in that, The compound containing a disulfide bond is selected from at least one of 4,4'-diaminodiphenyl disulfide, 2,2'-diaminodiphenyl disulfide, 5,5'-dithiobis(2-nitrobenzoic acid), diallyl trisulfide, dimethyl disulfide, dithiophene, lipoic acid, and amino acids.

5. The triboelectric sensor with a highly durable nano-sensing coating according to claim 1, characterized in that, The amino-containing modifier includes an amino-silane coupling agent.

6. The triboelectric sensor with a highly durable nano-sensing coating according to claim 1, characterized in that, The temperature of the modification treatment is 60-90°C, and the time is 30-40 min.

7. The application of the triboelectric sensor according to any one of claims 1-6 in detecting acidified pollutants in lubricating oil.

8. An integrated signal collection, processing, and transmission sensor system, characterized in that, Comprising: The triboelectric sensor, microprogram control unit, and transmitter / receiver unit according to any one of claims 1-6; Wherein, the triboelectric sensor is electrically connected to the microprogram control unit; The microprogram control unit is connected to the transmitter / receiver unit by wireless transmission.

9. A method for monitoring acidified pollutants in lubricating oil, characterized in that, Using the integrated signal collection, processing, and transmission sensor system according to claim 8 for monitoring.

10. A method for monitoring acidified pollutants in lubricating oil according to claim 9, characterized in that, Including the following steps: The microprogram control unit receives the voltage signal generated by the triboelectric sensor and processes it, analyzes the voltage signal to determine the content of acidified pollutants in the lubricating oil, and then uses the transmitter / receiver unit to wirelessly transmit the analyzed and processed data to a remote monitoring platform. When the content of acidified pollutants exceeds a preset threshold, the remote monitoring platform issues a warning signal through an alarm system.

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