A high-sensitivity and stable single-electrode triboelectric nanogenerator and a preparation method thereof

Abstract

The application discloses a kind of high sensitivity, stable single electrode friction nanogenerator, comprising: chemical copper plating fabric, metal electrode piece, PDMS coating layer;Wherein, metal electrode piece clamps chemical copper plating fabric one end partial area;PDMS coating layer is located outermost, completely wraps chemical copper plating fabric not being clamped by metal electrode piece area and the partial area of metal electrode piece adjacent to this area.It also discloses its preparation method, comprising: S1, plant fiber fabric is activated and handled;S2, is placed in chemical copper plating solution, obtains chemical copper plating fabric;S3, using metal electrode piece clamps chemical copper plating fabric one end partial area, obtains workpiece, is coated on the upper and lower two sides of workpiece mixed resin containing PDMS and curing agent, so that the PDMS after solidification completely wraps the area not being clamped by metal electrode piece and the partial area of metal electrode piece adjacent to this area.The friction nanogenerator described in the application has high sensitivity, excellent water resistance and compression resistance.

Description

TECHNICAL FIELD

[0001] The application belongs to the field of friction power generation, and particularly relates to a high-sensitivity and stable single-electrode friction nanogenerator and a preparation method thereof. BACKGROUND

[0002] With the rapid development of science and technology, the demand and dependence of society on electric energy are increasing. At present, the relatively mature power generation forms include magnetoelectricity, triboelectricity, piezoelectricity, thermoelectricity and photovoltaic electricity, etc. Among them, triboelectricity is valued due to the advantages of rich friction energy, various existence forms and simple triboelectric device manufacturing. A triboelectric nanogenerator (TENG) utilizes the coupling effect of triboelectricity and electrostatic induction to convert mechanical energy into corresponding periodic electric energy output, and has the advantages of large output power, high conversion efficiency, wide material selection, simple manufacturing and low cost.

[0003] The concept of TENG was first proposed by a team of Wang Zhonglin, and includes four basic modes, namely vertical contact-separation mode, sliding mode, single-electrode mode and independent layer mode. Among them, the TENGs in the vertical contact-separation mode and the sliding mode have electrodes connected by a load on the two friction materials in relative motion. However, in actual application, some free-moving components in the TENG structure are difficult to connect with the electrodes through wires. The single-electrode mode is composed of a free-moving friction layer and a fixed friction layer with an electrode attached, and based on the advantages of the single-electrode structure, it has very broad application prospects in the fields of intelligent sensing and human-computer interaction.

[0004] However, the output performance of the triboelectric nanogenerator is very susceptible to the real environment, and the stability of the triboelectric nanogenerator, especially the water resistance, is a bottleneck restricting its development, which to some extent limits its application. Therefore, it is of great significance to design a high-sensitivity and stable single-electrode triboelectric nanogenerator. SUMMARY

[0005] Based on the above technical problems, the application provides a high-sensitivity and stable single-electrode triboelectric nanogenerator and a preparation method thereof. The single-electrode triboelectric nanogenerator has high sensitivity, excellent water resistance and compression resistance, and can be applied in self-power supply of wearable products, tactile sensors and the like.

[0006] The specific scheme of the application is as follows

[0007] The application provides a high-sensitivity and stable single-electrode triboelectric nanogenerator, which comprises a chemical copper-plated fabric, a metal electrode sheet and a PDMS coating layer.

[0008] The metal electrode sheet clamps one end of the chemical copper-plated fabric, and the PDMS coating layer is located at the outermost layer and completely covers the area of the chemical copper-plated fabric not clamped by the metal electrode sheet and the part of the metal electrode sheet adjacent to the area.

[0009] Preferably, the chemical copper-plated fabric is prepared by activating a plant fiber fabric in a silver nitrate solution and then using a chemical copper plating process.

[0010] Preferably, the metal electrode sheet is selected from any one of a copper sheet, a silver sheet and an iron sheet.

[0011] Preferably, the metal electrode sheet has the same width as the chemical copper-plated fabric, and the length of the area of the chemical copper-plated fabric clamped by the metal electrode sheet is 2-30% of the length of the chemical copper-plated fabric.

[0012] The application also provides a preparation method of the high-sensitivity and stable single-electrode triboelectric nanogenerator, which comprises the following steps: S1, activating a plant fiber fabric in a silver nitrate solution; S2, immersing the activated plant fiber fabric in a chemical copper plating solution at 35-55 DEG C for 0.5-2 hours to obtain a chemical copper-plated fabric;

[0013] S3, clamping one end of the chemical copper-plated fabric with a metal electrode sheet to obtain a workpiece, and coating the upper and lower surfaces of the workpiece with a mixed resin containing PDMS and a curing agent, so that the cured PDMS completely covers the area of the chemical copper-plated fabric not clamped by the metal electrode sheet and the part of the metal electrode sheet adjacent to the area.

[0014] The application uses the hydrophilic groups on the surface of the plant fiber to adsorb Ag particles as catalytic centers of the electroless plating (EP) process, and then the Cu 2+ is reduced to Cu atoms in the plating solution and deposited on the surface of the fabric fiber to obtain a fabric with a chemical copper-plated surface.

[0015] Preferably, the concentration of the silver nitrate solution is 0.06-0.1 g / mL.

[0016] Preferably, the chemical copper plating solution comprises copper sulfate 11-58 g / L, ethylenediaminetetraacetic acid disodium 12-18 g / L, potassium sodium tartrate 12-18 g / L, formaldehyde 10-18 ml / L, potassium ferrocyanide 0.1-0.8 g / L, 2-2' bipyridine 0.01-0.05 g / L, polyethylene glycol 1-2 g / L and sodium hydroxide 12-18 g / L.

[0017] Preferably, in S3, the mass ratio of PDMS to curing agent in the mixed resin is 8-15:1.

[0018] The present application has the following advantages:

[0019] The friction nanogenerator of the structure has a PDMS encapsulated metal material with a high interface contact area, and a TENG device similar to a closed sandwich structure is obtained; the chemical copper-plated fabric is enclosed in the sandwich structure, and the hydrophobic and flexible PDMS is located in the outermost layer, so that the obtained friction nanogenerator has high sensitivity, excellent stability, flexibility and water resistance, stable output performance, and can be applied in self-power supply of wearable products, tactile sensors and the like.

[0020] In particular, the friction nanogenerator can be used for a tactile sensor, and the accuracy of material recognition is high. BRIEF DESCRIPTION OF DRAWINGS

[0021] Figure 1 SEM and mapping images of the cotton fabric used in Example 1;

[0022] Figure 2 SEM and mapping images of the chemical copper-plated cotton fabric prepared in Example 1;

[0023] Figure 3 XRD image of the chemical copper-plated cotton fabric prepared in Example 1;

[0024] Figure 4 X-ray photoelectron spectrograms of the cotton fabric, the activated cotton fabric and the chemical copper-plated cotton in Example 1;

[0025] Figure 5 Water resistance and compression resistance test images of the friction nanogenerator in Example 1;

[0026] Figure 6 Output voltage of the friction nanogenerator in Example 1 under different stresses;

[0027] Figure 7 Output signal analysis of the friction nanogenerator in Example 1 for material recognition;

[0028] Figure 8 Accuracy of the friction nanogenerator in Example 1 for material recognition;

[0029] Figure 9 Accuracy of the comparative friction nanogenerator for material recognition; DETAILED DESCRIPTION

[0030] The technical solutions of the present application will be described in detail below through specific embodiments, but it should be made clear that these embodiments are used for illustration only, but not to be interpreted as limiting the scope of the present application.

[0031] Embodiment 1

[0032] A high-sensitivity and stable single-electrode friction nanogenerator, comprising: a chemical copper-plated cotton cloth, a metal copper sheet, and a PDMS coating layer; wherein the metal copper sheet clamps one end of the chemical copper-plated cotton cloth in a partial region; the metal copper sheet is equal in width to the chemical copper-plated cotton cloth, and the length of the region clamped by the metal copper sheet is 25% of the length of the chemical copper-plated cotton cloth; specifically, the chemical copper-plated cotton cloth is a rectangle with a width of 6 cm and a length of 8 cm, the metal copper sheet has a width of 6 cm, and one end of the chemical copper-plated cotton cloth is clamped by the metal copper sheet, with a clamped region having a length of 2 cm.

[0033] The PDMS coating layer is located in the outermost layer and completely wraps the region of the chemical copper-plated cotton cloth that is not clamped by the metal copper sheet and the partial region of the metal copper sheet adjacent to the region.

[0034] The preparation method specifically comprises:

[0035] S1, drying the cleaned cotton fabric, and then immersing it in an AgNO3 solution with a concentration of 0.08 g / ml for 0.5 h, taking it out, and drying it to obtain an activated cotton fabric (hereinafter referred to as AC-Ag cotton in the following figures);

[0036] The SEM and mapping images of the cotton fabric used in this embodiment are shown in Figure 1 The appearance of N / O signal indicates that the cotton fabric surface has hydrophilic groups, which provides a basis for Ag adsorption;

[0037] S2, placing the activated cotton fabric in a chemical copper plating solution, placing the chemical copper plating solution in a water bath, adjusting the temperature of the water bath to 40℃, and chemical copper plating for 40 min, until the solution becomes transparent and the color of the cotton fabric turns red, to obtain a chemical copper-plated cotton cloth (hereinafter referred to as EP-Cu cotton in the following figures), washing, and drying;

[0038] The chemical copper plating solution formula is: (1) copper sulfate 15 g / L; (2) ethylenediaminetetraacetic acid disodium 14 g / L; (3) potassium sodium tartrate 14 g / L; (4) formaldehyde 15 ml / L; (5) potassium ferrocyanide 0.1 g / L; (6) 2-2' dipyridyl 0.02 g / L; (7) polyethylene glycol 1 g / L; (8) sodium hydroxide 14 g / L;

[0039] The SEM and mapping images of the EP-Cu cotton prepared in this embodiment are shown in Figure 2As shown in the figure, it can be seen that there are dense spherical Cu particles attached to the surface of the cotton fabric. The gap between the cotton fabric fibers and the Cu-coated particles increases the surface roughness, improves the interface contact area of the PDMS / chemical copper-plated cotton, and thus exhibits better and more sensitive output performance under the same external stress.

[0040] The XRD pattern of the chemical copper-plated cotton prepared in this example is shown in Figure 3 .

[0041] S3, cut the chemical copper-plated cotton obtained in S2 into a rectangle of 6 cm x 8 cm, with one end of the wide side wrapped with a 2 cm copper sheet, to obtain a workpiece; coat the upper and lower surfaces of the workpiece with a mixed resin containing PDMS and a curing agent, so that the cured PDMS completely wraps the area not clamped by the metal copper sheet and the adjacent part of the area, to obtain the target TENG device;

[0042] The weight ratio of PDMS to curing agent is 12.5:1.

[0043] The X-ray photoelectron spectrograms of the cotton fabric, the activated cotton fabric (AC-Ag cotton), and the chemical copper-plated cotton fabric (EP-Cu cotton) used in this example are shown in Figure 4 .

[0044] Example 2

[0045] A high-sensitivity and stable single-electrode triboelectric nanogenerator, comprising: a chemical copper-plated cotton fabric, a metal silver sheet, and a PDMS coating layer; wherein the metal silver sheet clamps a part of the area of one end of the chemical copper-plated cotton fabric; the metal silver sheet is equal in width to the chemical copper-plated cotton fabric, and the length of the area of the chemical copper-plated cotton fabric clamped by the metal silver sheet is 20% of the length of the chemical copper-plated cotton fabric; specifically, the chemical copper-plated cotton fabric is a rectangle of 6 cm in width and 8 cm in length, the metal silver sheet is 6 cm in width, and the one end of the chemical copper-plated cotton fabric is clamped by the metal silver sheet, and the length of the clamped area is 1.6 cm.

[0046] The PDMS coating layer is located in the outermost layer and completely wraps the area of the chemical copper-plated cotton fabric not clamped by the metal silver sheet and the part of the metal silver sheet adjacent to the area.

[0047] The preparation method specifically comprises:

[0048] S1, dry the cleaned cotton fabric, and then immerse it in an AgNO3 solution with a concentration of 0.08 g / ml for 0.5 h, take it out, and dry it to obtain an activated cotton fabric;

[0049] S2, the activated cotton fabric is placed in a chemical copper plating solution, the chemical copper plating solution is placed in a water bath, the temperature of the water bath is adjusted to 45 DEG C, and chemical copper plating is performed for 50 min, the solution becomes transparent and the color of the cotton fabric turns red, to obtain a chemical copper plated cotton fabric, which is cleaned and dried;

[0050] The chemical copper plating solution has the following formula: (1) copper sulfate 15 g / L; (2) ethylenediaminetetraacetic acid disodium salt 12 g / L; (3) potassium sodium tartrate 12 g / L; (4) formaldehyde 18 ml / L; (5) potassium ferrocyanide 0.4 g / L; (6) 2-2' bipyridine 0.03 g / L; (7) polyethylene glycol 1.5 g / L; (8) sodium hydroxide 14 g / L;

[0051] S3, the chemical copper plated cotton fabric obtained in S2 is cut into a rectangle of 6 cm x 8 cm, one end of which is wrapped with a silver sheet of 1.6 cm in width, to obtain a workpiece; the upper and lower surfaces of the workpiece are coated with a mixed resin containing PDMS and a curing agent, so that the cured PDMS completely wraps the area not clamped by the metal silver sheet and the partial area of the metal silver sheet adjacent to the area, to obtain a target TENG device;

[0052] The weight ratio of the PDMS and the curing agent is 14:1.

[0053] The performance of the friction nanogenerator described in Example 1 is tested, and the test method and results are shown as follows:

[0054] (1) Water resistance and compression resistance

[0055] The friction nanogenerator described in Example 1 is pressed with a 5 kg iron block and immersed in tap water for different times to test the stability of the prepared device, and it is found that the output performance of the friction nanogenerator does not fluctuate and is not measurably degraded within 30 days, as shown in Figure 5

[0056] Therefore, it is shown that the friction nanogenerator described in the application has good stability and water resistance, because the hydrophobic and flexible PDMS located on the outermost layer can protect the internal chemical copper plating surface and interface from external damage.

[0057] (2) Sensitivity and friction power generation test

[0058] The output voltage of the friction nanogenerator described in the application under different stresses is shown in Figure 6 ​It can be seen that (1) the minimum stress that the TENG device can perceive is 1.24 KPa, and the output voltage reaches 1.1 V, which shows that the friction nanogenerator prepared by the application has excellent sensitivity and can convert small mechanical energy into electrical energy; (2) when the external stress received by the friction generator increases from 1.24 KPa to 12.4 KPa, the output voltage gradually increases, and then sharply increases with the continuous increase of the external stress, which shows that the change of the output performance under the external stress is nonlinear and sudden. Therefore, under different stress ranges, the output performance, deformation mechanism and elastic modulus of the material of the friction generator are different.

[0059] The macroscopic deformation under low stress is caused by the elastic deformation of the PDMS coating layer, and the friction occurs at the interface of the object / PDMS under stress. With the increase of stress, in the direction perpendicular to the stress, when the sliding friction of the electroless copper plated fabric is exceeded, the electroless copper plated fabric begins to slide transversely, that is, the gap between the fabric fibers is opened, which leads to a sharp increase in the output voltage.

[0060] (3) Recognition performance

[0061] The friction nanogenerator described in the application can be used as a tactile sensor for object recognition.

[0062] The friction nanogenerator is attached to the joint of the robot finger, and when the finger touches the object to be recognized, the friction nanogenerator responds quickly and generates a stable output signal. The output signal analysis diagram of the material recognition is shown in Figure 7 It can be seen that when the single-electrode friction nanogenerator of the application is used as a tactile sensor to recognize objects, the output signal is a combination of the PDMS / EP-Cu and PDMS / recognized material output signals. It is this unique characteristic that enables high-precision recognition as a tactile sensor.

[0063] The application selects eight materials as target objects to construct a training set and a test set. After training the CNNs model, the signal generated by the friction nanogenerator of Example 1 is used as a self-powered tactile recognition, as shown in Figure 8 The recognition accuracy of the eight different materials is 99.48%.

[0064] In fact, as a comparison, the application also prepared a friction nanogenerator containing only PDMS and copper sheet, and the PDMS layer covers the surface of the copper sheet. The recognition test accuracy of the same eight materials according to the above method is shown in Figure 9 The recognition accuracy of the eight different materials is only 85.59%.

[0065] The above description is only the preferred embodiment of the present application, but the protection scope of the present application is not limited to this. Any person skilled in the art can make equivalent substitutions or changes according to the technical solution and the inventive concept of the present application within the technical range disclosed by the present application, which should be covered in the protection scope of the present application.

Claims

1. A method for preparing a high-sensitivity, stable single-electrode triboelectric nanogenerator, characterized in that, The application relates to a single-electrode friction nanogenerator and a preparation method thereof. S1, activating a plant fiber fabric in a silver nitrate solution; the silver nitrate solution has a concentration of 0.06-0.1 g / mL; S2, placing the activated plant fiber fabric in a chemical copper plating solution, soaking at 35-55 DEG C for 0.5-2 h to obtain a chemical copper plating fabric; the chemical copper plating solution comprises the following components: copper sulfate 11-58 g / L, ethylenediaminetetraacetic acid disodium 12-18 g / L, potassium sodium tartrate 12-18 g / L, formaldehyde 10-18 ml / L, potassium ferrocyanide 0.1-0.8 g / L, 2-2' dipyridyl 0.01-0.05 g / L, polyethylene glycol 1-2 g / L, and sodium hydroxide 12-18 g / L; S3, clamping one end of the chemical copper plating fabric with a metal electrode sheet to obtain a workpiece to be processed, coating the upper and lower surfaces of the workpiece to be processed with a mixed resin containing PDMS and a curing agent, and completely wrapping the area not clamped by the metal electrode sheet and the partial area of the metal electrode sheet adjacent to the area with the cured PDMS, so as to obtain the single-electrode friction nanogenerator; in S3, the mass ratio of the PDMS to the curing agent in the mixed resin is 8-15:

1.

2. A high-sensitivity, stable single-electrode tribo-nanogenerator, characterized in that, The application relates to a single-electrode friction nanogenerator and a preparation method thereof. The application relates to a single-electrode friction nanogenerator and a preparation method thereof. The application relates to a single-electrode friction nanogenerator and a preparation method thereof. The metal electrode sheet is selected from any one of a copper sheet, a silver sheet and an iron sheet.

3. The high sensitive, stable single-electrode tribo-nanogenerator according to claim 2, wherein, The metal electrode sheet and the chemical copper plating fabric are equal in width; the length of the area clamped by the metal electrode sheet is 2-30% of the length of the chemical copper plating fabric. 4.The high-sensitivity, stable single-electrode triboelectric nanogenerator according to claim 2 or 3, characterized in that, ​ 5.The high-sensitivity, stable single-electrode triboelectric nanogenerator according to claim 2 or 3, characterized in that, ​

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