Diamond friction power generation device and preparation method thereof

Abstract

This application relates to the field of triboelectric generation and discloses a diamond triboelectric device and its preparation method, comprising the following steps: using a laser to form a graphite electrode on the front surface or interior of a diamond substrate; depositing a metal film electrode on the bottom surface of the diamond substrate; welding a wire to the graphite electrode, and then welding the wire to the metal film electrode to form the diamond triboelectric device. The diamond triboelectric device of this application uses diamond as the main triboelectric material, which has the characteristics of high chemical stability, friction resistance, high hardness, long service life, and high environmental stability. Furthermore, the use of a laser to prepare the graphite electrode on the front surface or interior of the diamond substrate is simple, fast, and highly accurate.

Description

Technical Field

[0001] The present application relates to the field of triboelectric power generation, and mainly to a diamond triboelectric power generation device and a preparation method thereof. Background Art

[0002] When two dissimilar materials come into contact, they generate surface charge. Therefore, triboelectric devices can be designed using gases, liquids, solids, and other materials as contact materials. These devices are widely used to harvest various mechanical energy sources, such as triboelectricity generated by cycling, typing, walking, water flow, wind energy, or raindrops. They can be used to power wearable devices, harvest water flow energy, wind energy, and passive sensors for environmental monitoring.

[0003] Triboelectric devices generally require friction materials that are non-conductive, highly wear-resistant, hydrophobic, chemically inert, and highly stable to UV and other environmental conditions. Currently, these materials are typically prepared using organic polymers combined with electrodes. Diamond, with its advantages of high chemical inertness, good biocompatibility, strong resistance to UV and other environmental conditions, excellent tribological and mechanical properties, holds great promise for applications in triboelectric devices. However, due to high costs and complex electrode processing, diamond materials have not yet been used in triboelectric devices. Summary of the Invention

[0004] In view of the above-mentioned deficiencies in the prior art, the purpose of this application is to provide a diamond triboelectric power generation device and a preparation method thereof, aiming to provide a triboelectric power generation device with diamond as the main body.

[0005] The technical solution of this application is as follows:

[0006] A method for preparing a diamond triboelectric power generation device, comprising the following steps:

[0007] Utilizing laser to process the surface or interior of the front side of the diamond substrate to form a graphite electrode;

[0008] depositing a metal thin film electrode on the bottom surface of the diamond substrate;

[0009] The wire is welded to the graphite electrode, and the wire is welded to the metal film electrode to form the diamond friction power generation device.

[0010] The diamond triboelectric power generation device prepared by the method provided in this application is particularly suitable for harsh environments and long-life usage scenarios. Diamond is used as the main material for triboelectric power generation, and has the characteristics of high chemical stability, friction resistance, high hardness, long service life, and high environmental stability.

[0011] The method for preparing a diamond triboelectric power generation device, wherein the process of forming a graphite electrode on the surface or inside of the front surface of the diamond substrate using a laser comprises the following steps:

[0012] After focusing the laser through a telephoto lens, the laser focus is located on the surface or inside of the front surface of the diamond substrate. After gradually increasing the laser energy to above the threshold energy, the electric displacement motor is used to control the movement of the diamond substrate to form the graphite electrode.

[0013] This application uses graphite generated by the action of laser and diamond as an electrode, which is simple, fast and highly accurate, and does not require doping. In addition to preparing electrodes on the surface of the diamond substrate, electrodes can also be conveniently prepared inside the diamond substrate. The preparation speed is fast, pollution-free, highly repeatable and low cost.

[0014] The method for preparing a diamond triboelectric power generation device, wherein, when the laser is a nanosecond pulse laser, the overlap area of ​​the damaged areas required to be spaced apart when using the laser is greater than 50%, the focal length of the telephoto lens is greater than 80 cm, the laser is a short-wavelength laser, and the spot diameter is 100-1000 μm;

[0015] The length of the graphite electrode is 20% to 60% of the length of the diamond substrate, the width is 1 to 3 mm, the thickness is 3 to 20 μm, and the center of the electrode is adjacent to the center of the diamond substrate.

[0016] The method for preparing a diamond triboelectric power generation device, wherein the diamond substrate is prepared by the following steps:

[0017] Growing high-purity diamond on a diamond substrate to obtain the diamond substrate;

[0018] The diamond substrate is a natural diamond substrate or a diamond substrate grown by a vapor deposition method.

[0019] The method for preparing the diamond triboelectric power generation device, wherein the process of growing high-purity diamond on the diamond substrate is to grow the high-purity diamond on the diamond substrate using a microwave plasma chemical vapor deposition method, the microwave power is 3-10 kW, the flow ratio of hydrogen and methane is 20-30:1, the pressure is 80-120 Torr, the surface temperature of the diamond substrate during deposition is 750°C-1050°C, and the deposition rate is 5-20 μm / h.

[0020] The method for preparing a diamond triboelectric power generation device further comprises the following steps before performing the step of forming a graphite electrode on the surface or inside of the front side of the diamond substrate using a laser:

[0021] Polishing and cleaning of diamond substrate;

[0022] The cleaning process comprises placing the diamond substrate in a mixed solution for heating and cleaning, then ultrasonically cleaning with deionized water, and finally drying;

[0023] The mixed solution is prepared by mixing sulfuric acid with a mass concentration ratio of 20% to 50%, nitric acid with a mass concentration ratio of 10% to 20%, and perchloric acid with a mass concentration ratio of 10% to 45%, in a mass ratio of 1:1:1;

[0024] The temperature of the heating and cleaning is 50-80°C;

[0025] The polishing process is to polish the diamond substrate in sequence using a diamond grinding wheel and diamond powder;

[0026] The frequency of the ultrasonic cleaning is 40-80KHz, the power is 500-1500W, and the time is 10-30 minutes;

[0027] The heating and cleaning time is 10-15 minutes, and the drying temperature is 50-85°C.

[0028] The method for preparing a diamond triboelectric power generation device further comprises the following steps after the step of forming a graphite electrode on the surface or inside of the front side of the diamond substrate using a laser:

[0029] The diamond substrate is cleaned with a sulfuric acid and nitric acid mixed solution, then ultrasonically cleaned with deionized water, and finally dried;

[0030] The sulfuric acid and nitric acid mixed solution is prepared by mixing sulfuric acid with a mass concentration ratio of 2% to 5% and nitric acid with a mass concentration ratio of 1% to 3% in a mass ratio of 1:1;

[0031] During the ultrasonic cleaning process, the ultrasonic frequency is 40-60KHz, the power is 600-1000W, and the time is 10-20 minutes;

[0032] The drying temperature is 50-85°C.

[0033] The method for preparing the diamond triboelectric power generation device, wherein, in the step of depositing a metal thin film electrode on the bottom surface of the diamond substrate, the thickness of the metal thin film electrode is 80-500 nm;

[0034] The metal film electrode is gold, silver, copper, zinc or platinum;

[0035] The metal film electrode covers the bottom surface of the diamond substrate;

[0036] When the metal thin film electrode is deposited on the bottom surface of the diamond substrate by electron beam evaporation coating, the following steps are included:

[0037] The bottom surface of the diamond substrate is used as the coating surface and placed in an electron beam evaporation coating machine. The evaporation source is high-purity gold evaporation material. The vacuum is pumped to 10 -3 ~10 -6 After Pa, the electron gun operating voltage is 8~12KV, the current is 100~300A, and the evaporation rate is 0.2~0.4nm / s.

[0038] The method for preparing the diamond triboelectric power generation device, wherein the step of welding the wire to the graphite electrode is to connect the graphite electrode to one end of the wire under vacuum conditions or under the protection of an inert gas;

[0039] The vacuum condition is a vacuum degree of 10 -1 ~10 -3 Pa; the inert gas is argon or nitrogen.

[0040] A diamond triboelectric power generation device is prepared using the above-mentioned method for preparing a diamond triboelectric power generation device.

[0041] Beneficial effects: The diamond triboelectric device and its preparation method provided by the present application are particularly suitable for triboelectric devices with high environmental requirements and passive sensors for harsh environments. A diamond substrate with high chemical stability, friction resistance, high hardness, insulation, and low defect density is used as the main body of the triboelectric device. A laser is used to form a graphite electrode on the surface or inside of the front of the diamond substrate. The preparation of the electrode can be achieved relatively simply, especially the preparation of the electrode inside the diamond body, which is simpler than the doping method. In addition, a mixed heating method with multiple strong acids can significantly reduce the graphite phase on the surface of the diamond substrate in the initial state while producing hydrophobic properties. In application scenarios such as motion friction, raindrops, and waves, the diamond triboelectric device can realize surface charge changes to generate a potential difference. The diamond triboelectric device in the present application can be used for energy collection and monitoring. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] Figure 1 This is a schematic diagram of the cross-sectional structure of the diamond triboelectric power generation device of this application (graphite electrodes are drawn out from the surface).

[0043] Figure 2 This is a schematic diagram of the cross-sectional structure of the diamond triboelectric power generation device of this application (graphite electrodes are led out from the inside).

[0044] Figure 3 This is the electron microscope result of the graphite electrode of the diamond friction power generation device in Example 1 of the present application.

[0045] Figure 4 This is an enlarged view of the electron microscope result of the graphite electrode of the diamond friction power generation device in Example 1 of the present application.

[0046] Figure 5 This is a Raman spectrum of the diamond region of the diamond triboelectric device in Example 1 of the present application.

[0047] Figure 6 This is a Raman spectrum of the graphite electrode area of ​​the diamond triboelectric power generation device in Example 1 of the present application.

[0048] Explanation of reference numerals: 1. Diamond substrate; 2. Graphite electrode; 3. Metal film electrode. DETAILED DESCRIPTION

[0049] This application provides a diamond triboelectric device and a method for preparing the same. To clarify the purpose, technical solution, and effects of this application, the following further describes this application in detail. It should be understood that the specific embodiments described herein are intended only to illustrate this application and are not intended to limit this application.

[0050] Diamond possesses the essential properties required of a friction material. Compared to other existing friction materials, it offers unique advantages in terms of hardness and environmental tolerance. However, existing methods for forming electrodes by doping or coating diamond surfaces are cumbersome and require the use of other non-carbon materials, resulting in complex and costly processes. Therefore, there is a need to improve electrode fabrication methods and reduce the cost of diamond triboelectric power generation.

[0051] The present application provides a method for preparing a diamond triboelectric power generation device, comprising the following steps:

[0052] (1) Growth: Grow high-purity diamond on a diamond substrate to obtain a diamond base material.

[0053] In step (1), high-purity diamond can be grown on a diamond substrate by chemical vapor deposition or other methods. The thickness of the diamond substrate is 1-2 mm, and the thickness of the high-purity diamond is 3-10 mm.

[0054] In addition, a diamond triboelectric device can also be prepared directly on a diamond substrate. However, natural diamonds are expensive, while artificially grown diamonds are low in cost. Therefore, it is preferred to prepare the diamond substrate in step (1).

[0055] Furthermore, the purity requirement for high-purity diamond is a nitrogen content of ≤20ppm, i.e., Grade IIa. The purity requirement for diamond substrates can be slightly lower, i.e., Grade Ia or higher.

[0056] In the present application, the method for growing high-purity diamond can be microwave plasma chemical vapor deposition, hot filament deposition, DC sputtering and other growth methods. Preferably, microwave plasma chemical vapor deposition is used to grow high-purity diamond on a diamond substrate. The process parameters can be a microwave power supply power of 3~10KW, a hydrogen / methane flow ratio of 20~30:1, a pressure of 80~120Torr, a diamond substrate surface temperature of 750℃~1050℃ during deposition, and a deposition rate of 5~20μm / h.

[0057] The diamond substrate is a natural diamond substrate or a diamond substrate grown by vapor deposition. In the present application, a diamond substrate grown by vapor deposition is preferred because it is easy to obtain and has low cost.

[0058] (2) Laser cutting: Cut the diamond substrate and process it into the desired shape.

[0059] In step (2), the diamond substrate is cut by laser. The laser can be a nanosecond, picosecond or femtosecond pulse width laser. The shorter the pulse width, the smaller the thermal effect and the smaller the processing loss. Therefore, in this application, it is preferred to use a femtosecond laser to cut the diamond substrate.

[0060] Preferably, the central wavelength of the femtosecond laser is 800nm, the repetition frequency is ≥100kHz, and the pulse energy is ≥80μJ. The femtosecond laser has a short action time and a small thermal effect, which can minimize the loss and damage to the diamond substrate. At the same time, high repetition frequency and pulse energy can ensure the rapid cutting of high-purity diamonds.

[0061] (3) Polishing and cleaning: Polishing and cleaning of the diamond substrate.

[0062] In step (3), the polishing process can be performed by sequentially polishing the diamond substrate using a diamond grinding wheel and diamond micropowder, and the surface roughness of the diamond substrate is Ra ≤ 200 nm. The speed of the diamond grinding wheel can be 10 to 25 m / s, and the particle size of the diamond micropowder can be 1 to 50 μm. After the polishing process, it is beneficial to reduce the residual bonds and dangling bonds on the surface of the diamond substrate. At the same time, the flat surface is beneficial for the subsequent preparation of the triboelectric power generation device, making the triboelectric power generation efficiency higher.

[0063] In step (3), the cleaning process can be to prepare a mixed solution of sulfuric acid, nitric acid and perchloric acid, place the diamond substrate in the mixed solution for heating and cleaning, then perform ultrasonic cleaning with deionized water, and finally dry.

[0064] Furthermore, the mixed solution is prepared by mixing sulfuric acid (20% to 50% by mass), nitric acid (10% to 20% by mass), and perchloric acid (10% to 45% by mass) in a mass ratio of 1:1:1. This highly concentrated acid mixture effectively removes non-diamond phases from the surface of the diamond substrate. This mixed, heated cleaning treatment with multiple high-concentration strong acids can significantly reduce the initial graphite phase on the surface of the diamond substrate while simultaneously creating a hydrophobic property. This helps reduce the surface conductivity of the diamond substrate, making it easier to accumulate charge during friction. Furthermore, triboelectric devices with hydrophobic surfaces can be used in liquid environments, avoiding a decrease in triboelectric efficiency due to contamination.

[0065] In step (3), the heating temperature is preferably 50-80°C, and the heating cleaning time is 10-15 minutes. If the heating temperature is too low, the removal of non-diamond phases will be ineffective, and if the temperature is too high, the perchloric acid will become unstable and even explode.

[0066] In step (3), the frequency of ultrasonic cleaning is 40-80KHz, the power is 500-1500W, and the time is 10-30 minutes. In this application, a higher ultrasonic frequency range is selected for precision cleaning.

[0067] In step (3), the drying process can be carried out at a temperature of 50-85°C.

[0068] (4) Electrode preparation: Graphite electrodes are formed on the surface or inside of the front side of the diamond substrate using laser processing.

[0069] In step (4), a graphite electrode is prepared by direct laser ablation damage, which is simple, fast and highly accurate. Specifically, after focusing the laser with a telephoto lens, the laser focus is located on the surface or inside of the front of the diamond substrate. After gradually increasing the laser energy to above the threshold energy, the electric displacement motor is used to control the movement of the diamond substrate to obtain the graphite electrode. Among them, the threshold energy of different batches of diamond substrates (actually mainly refers to high-purity diamonds obtained by deposition) is different, generally ranging from 10 to 20 J / cm 2 between.

[0070] In step (4), the laser used is a nanosecond pulse or continuous laser.

[0071] Furthermore, when using nanosecond pulse laser, the overlap area of ​​the damaged areas required to be spaced apart is greater than 50%, and the focal length of the telephoto lens used is greater than 80cm. The use of a telephoto lens can more accurately control the focus position of the light spot. The wavelength of the nanosecond pulse laser can usually be selected from the 355nm, 532nm or 1064nm band, and the spot diameter can be 100-1000μm. In theory, the wavelength of the nanosecond pulse laser is preferably a short-wavelength laser, which can avoid the generation of large-area plasma ablation of the diamond substrate surface. In the embodiment of the present application, a nanosecond pulse laser with a wavelength of 1064nm is used.

[0072] In step (4), the length of the graphite electrode can be 20% to 60% of the length of the diamond substrate, the width can be 1 to 3 mm, and the thickness can be 3 to 20 μm. The center of the electrode is located near the center of the diamond substrate, which is conducive to the rapid accumulation and transfer of charges from the center.

[0073] The front side of the diamond substrate is a friction surface. Furthermore, the graphite electrode 2 can be drawn out from the surface of the diamond substrate 1 and connected to a wire, such as Figure 1 As shown, it is easy to prepare and convenient to connect with the wire; the graphite electrode 2 can also be drawn out from the inside of the diamond substrate 1 and connected with the wire, such as Figure 2 As shown, the diamond triboelectric power generation device prepared in this way can be used in a highly corrosive environment to avoid circuit corrosion, while having a high surface charge utilization rate.

[0074] (5) Cleaning: Clean the diamond substrate.

[0075] In step (5), the diamond substrate is cleaned by using a sulfuric acid and nitric acid mixed solution, then ultrasonically cleaning the diamond substrate with deionized water, and finally drying the diamond substrate. After the cleaning process, the splashes generated during the preparation of the graphite electrode can be removed to prevent the impact on charge accumulation.

[0076] Furthermore, the sulfuric acid and nitric acid mixed solution is obtained by mixing sulfuric acid with a mass concentration ratio of 2% to 5% and nitric acid with a mass concentration ratio of 1% to 3% in a mass ratio of 1:1.

[0077] Furthermore, during the ultrasonic cleaning process, the ultrasonic frequency is 40-60 kHz, the power is 500-1000 W, and the time is 10-20 minutes. During the drying process, the drying can be carried out at a temperature of 50-85°C.

[0078] (6) Deposition of metal film: Deposit a metal film electrode on the bottom surface of the diamond substrate.

[0079] In step (6), the deposition method can be electron beam evaporation coating, thermal evaporation coating or sputtering coating.

[0080] The thickness of the metal film electrode is required to be greater than 50nm to reduce the resistance value. The metal film electrode preferably covers the bottom surface of the diamond substrate, which can increase the contact area, facilitating charge collection and current conduction. Moreover, the larger the area of ​​the metal film electrode, the larger the collection range and the more charge can be obtained.

[0081] Preferably, a metal thin film electrode is deposited on the bottom surface of the diamond substrate by electron beam evaporation coating or sputtering coating. The thickness of the metal thin film electrode is preferably 80~500nm, more preferably 100~250nm. The metal thin film electrode is preferably gold, silver, copper, zinc or platinum with good conductivity.

[0082] Furthermore, when a metal thin film electrode is deposited on the bottom surface of the diamond substrate by electron beam evaporation coating, the following steps are included:

[0083] The bottom surface of the diamond substrate is used as the coating surface and placed in an electron beam evaporation coating machine. The evaporation source is high-purity gold evaporation material and the vacuum is pumped to 10 -3 ~10 -6 After Pa, the electron gun operating voltage is 8~12KV, the current is 100~300A, and the evaporation rate is 0.2~0.4nm / s.

[0084] Among them, high-purity gold evaporation material refers to gold with a purity equal to or higher than 99.999%.

[0085] During the electron beam evaporation coating process, a too high evaporation rate will cause an increase in large metal particles, while a too low evaporation rate will cause an increase in metal grain size and surface roughness. In this application, the preferred evaporation rate range is 0.2~0.4nm / s.

[0086] (7) Welding the wire to the graphite electrode and welding the wire to the metal film electrode to form a diamond friction power generation device.

[0087] In step (7), the prepared diamond triboelectric power generation device can be connected to an ammeter or a voltmeter as a passive sensing detection device, or can be connected to a load device or a battery to power or charge the device or battery.

[0088] In step (7), the wire can be made of copper, aluminum or other materials with good electrical conductivity.

[0089] In step (7), the graphite electrode and one end of the wire can be connected under vacuum or inert gas protection by using a spot welder or ordinary solder heating. Under vacuum or inert gas protection, the graphite electrode can be prevented from oxidation during high temperature welding. The vacuum degree can be 10 -1 ~10 -3Pa, the inert gas can be argon or nitrogen. The wire and the metal film electrode can be welded by using a spot welder or ordinary solder heating.

[0090] The present application also provides a diamond triboelectric power generation device, which is prepared by the preparation method of the diamond triboelectric power generation device provided in the present application. The diamond triboelectric power generation device provided in the present application, such as Figure 1 or Figure 2 As shown, it includes a diamond substrate 1, a graphite electrode 2 and a metal film electrode 3; the graphite electrode 2 is arranged on the surface or inside of the front side of the diamond substrate 1, and a wire is welded to the graphite electrode 2; the metal film electrode 3 is arranged on the bottom side of the diamond substrate 1, and a wire is welded to the metal film 3.

[0091] The diamond triboelectric device and its preparation method provided in this application have the following characteristics:

[0092] (1) The diamond triboelectric device provided in this application is particularly suitable for use in harsh environments and long life scenarios. Diamond is used as the main material for triboelectric power generation, and has the characteristics of high chemical stability, friction resistance, high hardness, long service life, and high environmental stability.

[0093] (2) This application uses graphite generated by the action of laser and diamond as an electrode, which is simple, fast and highly accurate, and does not require doping. In addition to preparing electrodes on the surface of the diamond substrate, electrodes can also be conveniently prepared inside the diamond substrate. The preparation speed is fast, pollution-free, highly repeatable and low cost;

[0094] (3) The diamond triboelectric power generation device prepared in this application has properties such as hydrophobicity. In application scenarios such as motion friction, raindrops, and waves, it can realize surface charge changes to generate potential differences, perform energy collection and monitoring, and can achieve self-cleaning, and has good applicability in water environments.

[0095] This application is not only applicable to single-crystal diamond triboelectric devices, but polycrystalline diamond triboelectric devices can also be realized using similar methods at a lower cost. Furthermore, the diamond triboelectric device preparation method described in this application can also be used to protect or modify the surface of conventional triboelectric devices. For example, a diamond film layer can be used as the upper surface of a triboelectric device, and a graphite electrode can be prepared on the diamond surface using a laser. This simple method can also ensure that the triboelectric device has a long life and high reliability, and its resistance to chemical corrosion and wear is greatly enhanced.

[0096] The present application is further described below through specific examples.

[0097] Example 1

[0098] First, the substrate is a CVD diamond flake product (length, width and height of 5mm*5mm*2mm). High-purity diamond with a thickness of 6mm is grown on the substrate using microwave plasma chemical vapor deposition to obtain a diamond substrate. The microwave power is 8kW, the hydrogen / methane flow ratio is 25:1, the pressure is 80~120Torr, the surface temperature of the diamond substrate is 850℃ during deposition, and the deposition rate is 12μm / h.

[0099] An 800nm ​​femtosecond laser was used to cut the diamond substrate into rectangular blocks (length, width and height of 5mm*5mm*5mm).

[0100] The diamond substrate is polished in sequence using a diamond grinding wheel and diamond micropowder to make the surface roughness of the diamond substrate Ra≤200nm, the linear speed of the diamond grinding wheel is 20m / s, and the particle size of the diamond micropowder is 25μm.

[0101] A mixed solution of sulfuric acid, nitric acid and perchloric acid was prepared, wherein the mass concentrations of sulfuric acid, nitric acid and perchloric acid were 30%, 10% and 25% respectively, and they were mixed in a mass ratio of 1:1:1; a diamond substrate was placed in the mixed solution for heating and cleaning at a heating temperature of 70°C for 15 minutes. The use of a higher concentration acid mixed solution can effectively remove non-diamond phases on the surface of the diamond substrate.

[0102] Ultrasonic cleaning was performed with deionized water at a frequency of 60 kHz, a power of 600 W, and a time of 20 minutes, followed by drying at 55°C.

[0103] After focusing the 1064nm laser with a telephoto lens, the laser focus is located on the surface of the diamond substrate. The lens focal length is 100cm, the spot diameter is 600μm, and the laser energy is gradually increased to the threshold energy of 12J / cm 2 In the above, the electric displacement motor was used to control the movement of the diamond substrate so that the overlap area of ​​the damaged areas between the intervals was greater than 50%, and a graphite electrode (with dimensions of 2.5 mm in length, 2 mm in width, and 20 μm in thickness) was obtained.

[0104] The diamond substrate was cleaned with a mixed solution of sulfuric acid and nitric acid, with the mass concentrations of sulfuric acid and nitric acid being 5% and 3% respectively, and the mixing ratio being 1:1 by mass. It was then ultrasonically cleaned with deionized water at a frequency of 60 kHz, a power of 600 W, and a time of 10 minutes, and then dried at 65°C.

[0105] The bottom surface of the diamond substrate is used as the coating surface and placed in an electron beam evaporation coating machine. The evaporation source is high-purity (99.999%) gold evaporation material, and the vacuum is pumped to 10 -4After Pa, the electron gun operating voltage is 10kV, the current is 200A, the evaporation rate is 0.2nm / s, and the thickness of the metal film electrode is 200nm.

[0106] The wire and the graphite electrode were placed in a vacuum (vacuum degree of 10 -1 Pa) and weld the wire to the metal film electrode to form a diamond triboelectric device, which can be used to connect to a load device or battery to power or charge the device or battery. The morphology of the graphite electrode prepared by laser on the surface of the diamond substrate was tested by electron microscopy. Figure 3 As shown in the figure, the morphology shows the ablation pit formed under a single pulse (1064nm wavelength). Figure 4 This is an enlarged view of the ablation pit, from which it can be seen that the ablation flatness is good.

[0107] Characterization of diamond region of diamond triboelectric device by Raman spectroscopy ( Figure 5 ) and graphite electrode ( Figure 6 ),like Figure 5 As shown, before laser processing, the diamond is at 1332.8cm -1 There are obvious peaks nearby, such as Figure 6 As shown, the graphite electrode after laser processing has a wavelength of 1350cm- 1 and 1580cm -1 There is an obvious peak nearby, indicating that the diamond-graphite transformation has been achieved.

[0108] The resistivity of the graphite electrode and diamond area was measured. The resistivity of the graphite electrode was 7×10 -3 Ω∙m, the resistivity of the diamond area is 5×10 15 Ω∙m, indicating that the graphite electrode prepared by laser processing has good conductivity.

[0109] The diamond triboelectric device was tested using flowing water, with a current of 1-5 μA and a voltage of 0.1-1 V. This indicates that the diamond triboelectric device of this embodiment can generate good electrical signals and can be used for signal monitoring of water, oil, corrosive liquids, etc.

[0110] It should be understood that the application of this application is not limited to the above examples. For ordinary technicians in this field, they can make improvements or changes based on the above description. All these improvements and changes should fall within the scope of protection of the claims attached to this application.

Claims

1. A method for preparing a diamond triboelectric power generation device, characterized in that: The following steps are involved: Utilizing laser to process the surface or interior of the front side of the diamond substrate to form a graphite electrode; depositing a metal thin film electrode on the bottom surface of the diamond substrate; Welding a wire to the graphite electrode and welding another wire to the metal film electrode to form the diamond friction power generation device; When a graphite electrode is formed inside the front surface of the diamond substrate by laser processing, the graphite electrode is led out from the interior of the diamond substrate and connected to the wire.

2. The method for preparing a diamond triboelectric power generation device according to claim 1, wherein: The process of forming a graphite electrode by laser processing on the surface or inside of the front side of the diamond substrate comprises the following steps: After focusing the laser with a telephoto lens, the laser focus is located on the surface or inside of the front surface of the diamond substrate. After gradually increasing the laser energy to above the threshold energy, the electric displacement motor is used to control the movement of the diamond substrate to form the graphite electrode.

3. The method for preparing a diamond triboelectric power generation device according to claim 2, wherein: When the laser is a nanosecond pulse laser, the overlap area of ​​the damaged areas required to be spaced apart when using the laser is greater than 50%, the focal length of the telephoto lens is greater than 80 cm, the laser is a short-wavelength laser, and the spot diameter is 100-1000 μm; The length of the graphite electrode is 20% to 60% of the length of the diamond substrate, the width is 1 to 3 mm, the thickness is 3 to 20 μm, and the center of the electrode is adjacent to the center of the diamond substrate.

4. The method for preparing a diamond triboelectric power generation device according to claim 1, wherein: The diamond substrate is prepared by the following steps: Growing high-purity diamond on a diamond substrate to obtain the diamond substrate; The diamond substrate is a natural diamond substrate or a diamond substrate grown by a vapor deposition method.

5. The method for preparing a diamond triboelectric power generation device according to claim 4, wherein: The process of growing high-purity diamond on the diamond substrate is to grow the high-purity diamond on the diamond substrate using a microwave plasma chemical vapor deposition method, with a microwave power of 3-10 kW, a flow ratio of hydrogen to methane of 20-30:1, a pressure of 80-120 Torr, a surface temperature of the diamond substrate of 750-1050° C. during deposition, and a deposition rate of 5-20 μm / h.

6. The method for preparing a diamond triboelectric power generation device according to claim 1, wherein: Before performing the above-mentioned step of forming a graphite electrode by laser processing on the surface or inside of the front side of the diamond substrate, the method further comprises the following steps: polishing and cleaning the diamond substrate; The cleaning process comprises placing the diamond substrate in a mixed solution for heating and cleaning, then ultrasonically cleaning with deionized water, and finally drying; The mixed solution is prepared by mixing sulfuric acid with a mass concentration ratio of 20% to 50%, nitric acid with a mass concentration ratio of 10% to 20%, and perchloric acid with a mass concentration ratio of 10% to 45%, in a mass ratio of 1:1:1; The temperature of the heating and cleaning is 50-80°C; The polishing process is to polish the diamond substrate in sequence using a diamond grinding wheel and diamond powder; The frequency of the ultrasonic cleaning is 40-80KHz, the power is 500-1500W, and the time is 10-30 minutes; The heating and cleaning time is 10-15 minutes, and the drying temperature is 50-85°C.

7. The method for preparing a diamond triboelectric power generation device according to claim 1, wherein: After the step of forming a graphite electrode on the surface or inside of the front side of the diamond substrate by laser processing, the method further comprises the following steps: The diamond substrate is cleaned with a sulfuric acid and nitric acid mixed solution, then ultrasonically cleaned with deionized water, and finally dried; The sulfuric acid and nitric acid mixed solution is prepared by mixing sulfuric acid with a mass concentration ratio of 2% to 5% and nitric acid with a mass concentration ratio of 1% to 3% in a mass ratio of 1:1; During the ultrasonic cleaning process, the ultrasonic frequency is 40-60KHz, the power is 600-1000W, and the time is 10-20 minutes; The drying temperature is 50-85°C.

8. The method for preparing a diamond triboelectric power generation device according to claim 1, wherein: In the step of depositing a metal thin film electrode on the bottom surface of the diamond substrate, the thickness of the metal thin film electrode is 80-500 nm; The metal film electrode is gold, silver, copper, zinc or platinum; The metal film electrode covers the bottom surface of the diamond substrate; When the metal thin film electrode is deposited on the bottom surface of the diamond substrate by electron beam evaporation coating, the following steps are included: The bottom surface of the diamond substrate is used as the coating surface and placed in an electron beam evaporation coating machine. The evaporation source is high-purity gold evaporation material. The vacuum is pumped to 10 -3 ~10 -6 After Pa, the electron gun operating voltage is 8~12KV, the current is 100~300A, and the evaporation rate is 0.2~0.4nm / s.

9. The method for preparing a diamond triboelectric power generation device according to claim 1, wherein: The step of welding the wire to the graphite electrode is to connect the graphite electrode to one end of the wire under vacuum conditions or under the protection of an inert gas; The vacuum condition is a vacuum degree of 10 -1 ~10 -3 Pa; the inert gas is argon or nitrogen.

10. A diamond triboelectric power generation device, characterized in that: The diamond friction power generation device is prepared by the preparation method of any one of claims 1 to 9.

Images