Triboelectric composition for triboelectric nanogenerator and triboelectric nanogenerator including the same

Abstract

The present invention relates to a triboelectric composition for a triboelectric nanogenerator and a triboelectric nanogenerator including the same. One embodiment includes a triboelectric nanogenerator using a triboelectric positive electrode composition including a graphene oxide-based nanomaterial as a triboelectric positive electrode layer. Another embodiment includes a triboelectric nanogenerator using a triboelectric negative electrode composition including any one of fluorine-functionalized graphite, perovskite material, and molybdenum sulfide (MoS2) as a triboelectric negative electrode layer.

Description

[Technical Field]

[0001] The present invention relates to a triboelectric composition for a triboelectric nanogenerator and a triboelectric nanogenerator including the same. One embodiment includes a triboelectric nanogenerator using a triboelectric positive electrode composition including a graphene oxide-based nanomaterial as a triboelectric positive electrode layer. Another embodiment includes a triboelectric nanogenerator using a triboelectric negative electrode composition including any one of fluorine-functionalized graphite, perovskite material, and molybdenum sulfide (MoS2) as a triboelectric negative electrode layer.

[0002] This invention is the result of research supported by the Korea Research Foundation's "Next-generation highly transparent and highly stretchable sensors using non-aqueous-based high-performance multifunctional ion-conductive non-ionic polymer gels and their application to electrochemical display elements" project (No. 1711190086) funded by the government (Ministry of Science and ICT) from March 1, 2021 to February 29, 2024, and the Korea Institute for Technology Evaluation and Management's "Development of manufacturing and utilization technology for piezoelectric fluorine-based copolymer resins" project (No. 1415185197) funded by the government (Ministry of Trade, Industry and Energy) from April 1, 2021 to December 31, 2024. [Background technology]

[0003] A triboelectric nanogenerator (TENG) is a device that generates electrical energy by utilizing static electricity generated when two dissimilar materials come into contact or rub against each other. Triboelectric nanogenerators are less harmful to the environment than traditional power generation methods, operate as a renewable energy source, and are environmentally friendly because they can be made compact, making them suitable for a variety of applications, and much research is being done on them. Such triboelectric nanogenerators can be used in biosensors, to supply electricity to devices inserted or attached to the body, and to generate electricity continuously using human movement.

[0004] However, triboelectric nanogenerators currently face technical limitations such as low power density and high internal impedance, etc. To solve these problems, a triboelectric composition with high electromechanical conversion efficiency must be provided.

[0005] Related prior art documents include Patent Document 1. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Korean Patent Publication No. 10-2023-0134367 Summary of the Invention [Problem to be solved by the invention]

[0007] An object of the present invention is to provide a triboelectric composition for a triboelectric nanogenerator having high power density and low impedance, and a triboelectric nanogenerator including the same.

[0008] The present invention also has high sensitivity.

[0009] The present invention also has high mechanical stability and durability.

[0010] The present invention also has excellent efficiency at low pressures.

[0011] Furthermore, the present invention has excellent sensitivity and can use a variety of sources as a power source. [Means for solving the problem]

[0012] A triboelectric positive electrode composition for a triboelectric nanogenerator according to an embodiment of the present invention includes reduced graphene oxide functionalized with tetraethylenepentamine (rGO-TEPA) and a first polymer.

[0013] The content of the reduced graphene oxide functionalized with tetraethylenepentamine may be 1 to 10 parts by weight based on 100 parts by weight of the first polymer.

[0014] A triboelectric negative electrode composition for a triboelectric nanogenerator according to an embodiment of the present invention may include any one of fluorine-functionalized graphite, a perovskite material, and molybdenum sulfide (MoS2), and a second polymer.

[0015] The content of the fluorine-functionalized graphite may be 5 to 15 parts by weight per 100 parts by weight of the second polymer, the content of the perovskite material may be 5 to 10 parts by weight per 100 parts by weight of the second polymer, and the content of the molybdenum sulfide may be 0.2 to 2.0 parts by weight per 100 parts by weight of the second polymer. The perovskite material may be barium strontium titanate.

[0016] A triboelectric nanogenerator according to an embodiment of the present invention includes a tribo-positive layer and a tribo-negative layer.

[0017] The triboelectric positive electrode layer may include reduced graphene oxide functionalized with tetraethylenepentamine (rGO-TEPA) and a first polymer, and the triboelectric negative electrode layer may include any one of fluorine-functionalized graphite, perovskite material, and molybdenum sulfide (MoS2), and a second polymer.

[0018] The triboelectrically charged positive electrode layer may be fabricated by an electrodischarge method using a first mixture in which the tetraethylenepentamine-functionalized reduced graphene oxide and a first polymer are mixed.

[0019] The triboelectrically charged negative electrode layer may be manufactured by a casting method using a second mixture obtained by mixing any one of the fluorine-functionalized graphite, the perovskite material, and molybdenum sulfide (MoS2) with a second polymer. [Effects of the Invention]

[0020] A triboelectric composition for a triboelectric nanogenerator and a triboelectric nanogenerator including the same according to an embodiment of the present invention have high power density and low impedance.

[0021] The present invention also has high sensitivity.

[0022] The present invention also has high mechanical stability and durability.

[0023] The present invention also has excellent efficiency at low pressures.

[0024] Furthermore, the present invention has excellent sensitivity and can use a variety of sources as a power source. [Brief explanation of the drawings]

[0025] [Figure 1] 1 is a conceptual diagram of a triboelectric nanogenerator according to an embodiment of the present invention. [Figure 2] 1A and 1B are SEM photographs of reduced graphene oxide functionalized with tetraethylenepentamine, positive electrode comparative example 1, and positive electrode examples 1 to 4. [Figure 3] 1 shows XRD analysis results for positive electrode Comparative Example 1, reduced graphene oxide functionalized with tetraethylenepentamine, and positive electrode Example 4. [Figure 4] 1 is an SEM photograph of negative electrode Example 3. [Figure 5] 1 is a photograph showing the EDS results of negative electrode Example 3. [Figure 6] 1 shows XRD analysis results of silicone rubber, fluorine-functionalized graphite, and negative electrode example 3. [Figure 7] 1 shows the measurement results of the dielectric constant and dielectric loss for negative electrode examples 1 to 3 and negative electrode comparative example 1. [Figure 8] 1 shows the results of measuring the surface potential over time for Negative Electrode Examples 1 to 3 and Negative Electrode Comparative Example 1. [Figure 9] (a) SEM photograph of negative electrode Example 5, (b) SEM photograph of negative electrode Example 7. [Figure 10] 1 shows the results of XRD analysis of negative electrode examples 5 to 7 and negative electrode comparative example 2. [Figure 11] 1 shows the measurement results of the dielectric constant and dielectric loss for negative electrode examples 5 to 7 and negative electrode comparative example 2. [Figure 12] (a) SEM photograph of negative electrode Example 11, (b) SEM photograph of negative electrode Comparative Example 3. [Figure 13] 1 shows the results of XRD analysis of negative electrode Examples 8 to 11. [Figure 14] 1 shows the measurement results of the dielectric constant and dielectric loss for negative electrode examples 8 to 11 and negative electrode comparative example 3. [Figure 15] 1 shows the measurement results of VOC and ISC of triboelectric nanogenerators in which positive electrode examples 1 to 4 and positive electrode comparative example 1 are combined with negative electrode comparative example 1 and negative electrode examples 1 to 3. [Figure 16] 10 shows the results of measuring the electrical characteristics depending on the load in a triboelectric nanogenerator in which positive electrode Example 2 and negative electrode Example 3 are combined. [Figure 17] 1 shows the measurement results of VOC, ISC, and Q of a triboelectric nanogenerator in which positive electrode examples 1 to 3 and positive electrode comparative example 1 are combined with negative electrode examples 5 to 7 and negative electrode comparative example 2. [Figure 18] 1 shows the results of measuring the electrical characteristics depending on the load in a triboelectric nanogenerator in which positive electrode Example 2 and negative electrode Example 5 are combined. [Figure 19] 1 shows the VOC and ISC measurement results of a triboelectric nanogenerator in which positive electrode example 2, negative electrode examples 8 to 11, and negative electrode comparative example 3 are combined. [Figure 20] 10 shows the results of measuring the electrical characteristics depending on the load in a triboelectric nanogenerator in which positive electrode Example 2 and negative electrode Example 11 are combined. [Figure 21] 1 is a structural formula of reduced graphene oxide functionalized with tetraethylenepentamine. DETAILED DESCRIPTION OF THE INVENTION

[0026] Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings. However, the embodiments of the present invention may be modified into various other forms, and the scope of the present invention is not limited to the embodiments described below. Furthermore, the embodiments of the present invention are provided to more completely explain the present invention to those having average knowledge in the relevant technical field.

[0027] Triboelectric positive electrode compositions for triboelectric nanogenerators A triboelectric positive electrode composition for a triboelectric nanogenerator according to an embodiment of the present invention includes reduced graphene oxide functionalized with tetraethylenepentamine (rGO-TEPA) and a first polymer.

[0028] The reduced graphene oxide functionalized with tetraethylenepentamine is a material that easily attracts electricity to its surroundings or easily releases electrons, and in the present invention, it can function to easily release electrons by contacting with a negative electrode triboelectric material. The reduced graphene oxide functionalized with tetraethylenepentamine can be represented by the structural formula shown in Figure 21.

[0029] In one embodiment, the content of the reduced graphene oxide functionalized with tetraethylenepentamine may be 1 to 10 parts by weight, preferably 1 to 3 parts by weight, based on 100 parts by weight of the first polymer. If the content is too low or too high, power generation efficiency may decrease.

[0030] The first polymer allows the positive electrode triboelectric material to have a uniform shape so that it can be used as a triboelectric positive electrode layer, and the tetraethylenepentamine-functionalized reduced graphene oxide is uniformly dispersed to provide high power density.

[0031] The first polymer may be a polymer resin cured by a curing agent, and preferably, the polymer resin is polyurethane (PU).

[0032] The triboelectric positive electrode composition for a triboelectric nanogenerator can be cured and dried to form a film-like triboelectric layer, which can be placed on an electrode and used as a triboelectric nanogenerator.

[0033] A method for fabricating a triboelectric layer for a triboelectric nanogenerator according to an embodiment of the present invention includes mixing tetraethylenepentamine-functionalized reduced graphene oxide (rGO-TEPA), a first polymer, and a solvent to prepare a mixture, forming the mixture into a sheet, and then disposing the prepared triboelectric layer on an electrode.

[0034] In the step of preparing a mixture by mixing the tetraethylenepentamine-functionalized reduced graphene oxide, the first polymer, and the solvent, the reduced graphene oxide and the first polymer are as described above. In this step, the content of the tetraethylenepentamine-functionalized reduced graphene oxide may be 1 to 10 parts by weight, preferably 1 to 3 parts by weight, per 100 parts by weight of the first polymer.

[0035] The solvent is not particularly limited as long as it can dissolve the first polymer. The solvent may be an organic solvent, preferably N,N-dimethylformamide (DMF) or tetrahydrofuran (THF).

[0036] This step may be performed by stirring the mixture with a stirrer under heating, at a temperature of 50 to 70° C., for 5 to 10 hours.

[0037] The step of forming the mixture into a sheet may be performed by electrospinning the mixture. In one embodiment, using electrospinning can effectively demonstrate the electrical properties of the reduced graphene oxide functionalized with tetraethylenepentamine, allowing it to react and generate electricity even under low pressure, thereby improving power generation efficiency.

[0038] The sheet produced in this step can be several tens of microns thick.

[0039] After the fabrication of the triboelectric layer is completed through the previous process, a further step may be performed: placing the triboelectric layer on an electrode. The electrode may be made of a conductive material, such as a metal or alloy. This step may involve attaching the triboelectric layer to the electrode using an adhesive, or by applying pressure or heat.

[0040] In other embodiments, this step can be omitted by casting the mixture onto an electrode in the step of forming the mixture into a film.

[0041] The triboelectric layer thus produced may be used as a triboelectric positive electrode layer or a triboelectric negative electrode layer, preferably as a triboelectric positive electrode layer.

[0042] Triboelectric negative electrode compositions for triboelectric nanogenerators A triboelectric negative electrode composition for a triboelectric nanogenerator according to an embodiment of the present invention may include any one of fluorine-functionalized graphite, a perovskite material, and molybdenum sulfide (MoS2), and a second polymer.

[0043] The present invention may include any one of luolin-functionalized graphite, perovskite materials, and molybdenum sulfide (MoS2), which will be described below.

[0044] Described below are triboelectric negative electrode compositions for triboelectric nanogenerators that include fluorine-functionalized graphite.

[0045] The fluorine-functionalized graphite is a material that easily attracts electricity to its surroundings or easily releases electrons, and in the present invention, it can easily attract electrons by contacting with a positive electrode triboelectric charging material. The fluorine-functionalized graphite can be represented by the following Chemical Formula 1, where x is preferably 1.1 to increase the electron collection efficiency.

[0046] [ka]

[0047] In one embodiment, the content of the fluorine-functionalized graphite may be 5 to 17 parts by weight, preferably 13 to 17 parts by weight, based on 100 parts by weight of the first polymer. If the content of the fluorine-functionalized graphite is too high, it may not harden to form a film, whereas if the content is too low, it may result in low power density and increased impedance.

[0048] The second polymer allows the anode triboelectric material to have a uniform shape, allowing it to be used as a film-like triboelectric layer, and the fluorine-functionalized graphite is uniformly dispersed, resulting in high power density.

[0049] The second polymer may be a polymer resin cured with a curing agent, and preferably the polymer resin may be silicone rubber. Silicon rubber has superior tensile strength and abrasion resistance, chemical stability, and processability compared to other polymer materials. The silicone rubber may be PDMS (polydimethylsiloxane) or PDMS containing a platinum catalyst. The PDMS containing a platinum catalyst is available from Smooth-On's Ecoflex TMBy specifying the second polymer in this way, it is possible to maintain a constant shape even when the content of fluorine-functionalized graphite is high.

[0050] Described below are triboelectric negative electrode compositions for triboelectric nanogenerators that include perovskite materials.

[0051] The perovskite material is a material that easily attracts electricity to its surroundings or easily emits electrons, and in the present invention, it can easily attract electrons by contacting with a positive electrode triboelectric material. The perovskite material may be barium strontium titanate, which can be represented by Chemical Formula 2.

[0052] [ka]

[0053] In one embodiment, the content of the perovskite material may be 5 to 10 parts by weight, preferably 5 to 8 parts by weight, based on 100 parts by weight of the second polymer. If the content of the perovskite material is too high or too low, problems such as low power density and increased impedance may occur.

[0054] The second polymer allows the negative electrode triboelectric material to have a uniform shape so that it can be used as an electrode, and the fluorocarbon is uniformly dispersed to provide high power density.

[0055] The second polymer may be a polymer resin cured with a curing agent, and preferably the polymer resin may be silicone rubber. Silicon rubber has superior tensile strength and abrasion resistance, chemical stability, and processability compared to other polymer materials. The silicone rubber may be PDMS or PDMS containing a platinum catalyst. The PDMS containing a platinum catalyst is Ecoflex by Smooth-On Co., Ltd. TMBy specifying the second polymer as such, it is possible to maintain a constant shape upon hardening even when the content of fluorocarbon is high.

[0056] Below, we describe a triboelectric negative electrode composition for a triboelectric nanogenerator that includes molybdenum sulfide (MoS2).

[0057] The molybdenum sulfide (MoS2) is a material that easily attracts electricity to its surroundings or easily releases electrons, and in the present invention, it can easily attract electrons by contacting with the positive electrode triboelectric material.

[0058] In one embodiment, the content of the molybdenum sulfide may be 0.2 to 2.0 parts by weight, preferably 1 to 1.5 parts by weight, based on 100 parts by weight of the second polymer. If the content is too high, the polymer may not be hardened, and if the content is too low, the power generation efficiency may decrease.

[0059] In one embodiment, the average particle size of the molybdenum sulfide may be 50 to 100 nm. If the particle size deviates from this range, dispersion may be difficult, and power generation efficiency may decrease.

[0060] The second polymer allows the anode triboelectric material to have a uniform shape so that it can be used as a triboelectric layer, and the molybdenum sulfide is uniformly dispersed to provide high power density.

[0061] The second polymer may be a polymer resin cured with a curing agent, and preferably the polymer resin may be silicone rubber. Silicon rubber has superior tensile strength and abrasion resistance, chemical stability, and processability compared to other polymer materials. The silicone rubber may be PDMS or PDMS containing a platinum catalyst. The PDMS containing a platinum catalyst is Ecoflex by Smooth-On Co., Ltd. TM By specifying the second polymer as such, it is possible to harden and maintain a constant shape even when the content of molybdenum sulfide is high.

[0062] The triboelectric negative electrode composition for a triboelectric nanogenerator can be cured and dried to form a film-like triboelectric layer, which can be placed on an electrode and used as a triboelectric nanogenerator.

[0063] A method for manufacturing a triboelectric layer for a triboelectric nanogenerator according to an embodiment of the present invention may include the steps of: mixing one of fluorine-functionalized graphite, a perovskite material, and molybdenum sulfide (MoS) with a second polymer to prepare a mixture; forming the mixture into a film; and drying the film-formed mixture. The method may further include disposing the triboelectric layer prepared by the method on a current collector.

[0064] In the step of preparing a mixture by mixing any one of fluorine-functionalized graphite, perovskite material, and molybdenum sulfide (MoS2) with a second polymer, the any one of fluorine-functionalized graphite, perovskite material, and molybdenum sulfide (MoS2) and the second polymer may be the same as those described above.

[0065] The step of forming the mixture into a film can be performed by a general method for producing a film using a polymer resin. In one example, the film can be produced by a melt casting method. In this step, the thickness of the film can be adjusted using a doctor blade or the like.

[0066] Next, the mixture formed into a film is dried. This step can be performed by leaving the mixture at room temperature (20 to 30°C) for 20 to 30 hours. The thickness of the triboelectric layer (film) after drying can be 200 to 250 μm. If necessary, the triboelectric layer can be cut to a certain size.

[0067] After the fabrication of the triboelectric layer is completed through the previous process, a further step may be performed in which the triboelectric layer is disposed on an electrode. The electrode is made of a conductive material, such as a metal or alloy. This step may involve attaching the triboelectric layer and the electrode using an adhesive, or by applying pressure or heat.

[0068] In other embodiments, this step can be omitted by casting the mixture onto an electrode in the step of forming the mixture into a film.

[0069] The triboelectric layer thus produced may be used as a triboelectric positive or negative electrode layer, preferably as a negative electrode layer.

[0070] Triboelectric nanogenerator FIG. 1 is a conceptual diagram of a triboelectric nanogenerator 100 according to an embodiment of the present invention. Referring to FIG. 1, a triboelectric nanogenerator according to an embodiment of the present invention includes a tribocharged positive electrode layer 120 and a tribocharged negative electrode layer 110. The nanogenerator may also include an electrode 130' disposed on the tribocharged positive electrode layer 120 and an electrode 130 disposed on the tribocharged negative electrode layer 110. The nanogenerator may also include support plates 140, 140' disposed on the other side of each of the electrodes 130, 130' to protect them. The tribocharged positive electrode layer 120 and the tribocharged negative electrode layer 110 may be electrically connected to each other so that electrons can move between them, and thus may be directly or indirectly connected to each other. One embodiment may further include a spacer 150 disposed between the tribocharged positive electrode layer 120 and the tribocharged negative electrode layer 110. Thus, the tribocharged positive electrode layer 120 and the tribocharged negative electrode layer 110 are normally spaced apart from each other and may be configured to come into contact with each other when external pressure is applied.

[0071] Either the tribocharged positive electrode layer or the tribocharged negative electrode layer includes the tribocharged positive electrode composition or the tribocharged negative electrode composition described above. Preferably, the tribocharged positive electrode layer includes reduced graphene oxide functionalized with tetraethylenepentamine (rGO-TEPA) and a first polymer. Also, preferably, the tribocharged negative electrode layer includes any one of fluorine-functionalized graphite, perovskite materials, and molybdenum sulfide (MoS2) and a second polymer.

[0072] The triboelectric nanogenerator may include other components commonly used in the relevant field, and is not particularly limited.

[0073] Example: Fabrication of Triboelectric Positive Electrode Layer Positive electrode example 1 (PUAFG01): Polyurethane is Selectophore from Sigma-Aldrich TM The reduced graphene oxide functionalized with tetraethylenepentamine was obtained from Sigma-Aldrich. N,N-dimethylformamide (DMF, 99.8%) was obtained from Acros Organics, and tetrahydrofuran (THF >99% purity) was obtained from Daejung Chemicals & Metals Co., Ltd. 1 g of polyurethane and 0.01 g of reduced graphene oxide functionalized with tetraethylenepentamine were added to 9 g of a 4:6 volumetric mixture of DMF and THF and stirred at 60°C and 500 rpm for 8 hours. The mixture was electro-emitted using an electro-emitter under the following conditions: voltage 10 kV, tip-to-collector distance 12 cm, emission rate 1 mL / h, collector speed 100 rpm, temperature 10-12°C, and relative humidity 40-50% to produce a sheet. The electro-emitted sheet was fabricated on a current collector wrapped in aluminum foil. The sheet-like mixture was placed in an oven and dried for 10 hours at 80°C. This produced a triboelectrically charged positive electrode layer with 1 part by weight of reduced graphene oxide functionalized with tetraethylenepentamine per 100 parts by weight of polyurethane. The thickness of the triboelectrically charged positive electrode layer was 30-40±2 μm.

[0074] Positive electrode example 2 (PUAFG02): Prepared in the same manner as positive electrode example 1, except that 0.02 g of reduced graphene oxide functionalized with tetraethylenepentamine was added to prepare a triboelectric positive electrode layer containing 2 parts by weight of reduced graphene oxide functionalized with tetraethylenepentamine per 100 parts by weight of polyurethane.

[0075] Positive electrode example 3 (PUAFG05): Prepared in the same manner as positive electrode example 1, except that 0.05 g of reduced graphene oxide functionalized with tetraethylenepentamine was added to prepare a triboelectric positive electrode layer containing 5 parts by weight of reduced graphene oxide functionalized with tetraethylenepentamine per 100 parts by weight of polyurethane.

[0076] Positive electrode example 4 (PUAFG010): This was prepared in the same manner as positive electrode example 1, except that 0.10 g of reduced graphene oxide functionalized with tetraethylenepentamine was added to prepare a triboelectric positive electrode layer containing 10 parts by weight of reduced graphene oxide functionalized with tetraethylenepentamine per 100 parts by weight of polyurethane.

[0077] Comparative positive electrode (PU): Prepared in the same manner as in Positive Electrode Example 1, except that reduced graphene oxide functionalized with tetraethylenepentamine was not added.

[0078] Example: Fabrication of Triboelectric Negative Electrode Layer (Fluorine-Functionalized Graphite) Negative electrode example 1 (EC5FG): Fluorine-functionalized graphite was provided by Sigma-Aldrich, and silicone rubber was Ecoflex from Smooth-On. TM-00-30 was prepared. 10 g of silicone rubber containing components A and B was mixed with 0.5 g of fluorine-functionalized graphite and thoroughly stirred to produce a mixture. The mixture was then poured onto sandpaper and sanded to a thickness of 235±5 μm using a doctor blade, followed by drying at room temperature (20-25°C) for 24 hours. This resulted in a triboelectrically charged negative electrode layer containing 5 parts by weight of fluorine-functionalized graphite per 100 parts by weight of silicone rubber. The thickness of the resulting triboelectrically charged negative electrode layer was 235±5 μm.

[0079] Negative electrode example 2 (EC10FG): This was prepared in the same manner as negative electrode example 1, except that 1.0 g of fluorine-functionalized graphite was added to prepare a triboelectric negative electrode layer containing 10 parts by weight of fluorine-functionalized graphite per 100 parts by weight of silicone rubber.

[0080] Negative electrode example 3 (EC15FG): Prepared in the same manner as negative electrode example 1, except that 1.5 g of fluorine-functionalized graphite was added to prepare a triboelectric negative electrode layer with 15 parts by weight of fluorine-functionalized graphite per 100 parts by weight of silicone rubber.

[0081] Negative electrode example 4 (EC20FG): This was prepared in the same manner as negative electrode example 1, except that 2.0 g of fluorine-functionalized graphite was added to prepare a triboelectric negative electrode layer containing 20 parts by weight of fluorine-functionalized graphite per 100 parts by weight of silicone rubber.

[0082] Comparative negative electrode (EC): Produced in the same manner as in Example 1, except that fluorine-functionalized graphite was not added.

[0083] Example: Fabrication of a Triboelectric Negative Electrode Layer (Barium Strontium Titanate) Negative electrode example 5 (EC5): Barium strontium titanate powder was prepared by Sigma-Aldrich, and silicone rubber was Ecoflex by Smooth-On. TM-00-30 was prepared. 10 g of silicone rubber A was mixed with 0.55 g of barium strontium titanate powder, and then 1 g of silicone rubber B was added and thoroughly stirred to produce a mixture. The mixture was then poured onto sandpaper and sanded using a doctor blade to a thickness of 30±5 μm, after which it was dried at room temperature (20-25°C) for 24 hours. This resulted in a tribo-charged negative electrode layer with 5 parts by weight of barium strontium titanate per 100 parts by weight of silicone rubber. The thickness of the produced tribo-charged negative electrode layer was 20±5 μm.

[0084] Negative Electrode Example 6 (EC 7.5): This was prepared in the same manner as Negative Electrode Example 5, except that 0.825 g of barium strontium titanate was added to prepare a triboelectrically charged negative electrode layer of 7.5 parts by weight of barium strontium titanate per 100 parts by weight of silicone rubber.

[0085] Negative Electrode Example 7 (EC10): Produced in the same manner as Negative Electrode Example 5, except that 1.1 g of barium strontium titanate was added to produce a triboelectrically charged negative electrode layer of 10 parts by weight of barium strontium titanate per 100 parts by weight of silicone rubber.

[0086] Comparative Example of Negative Electrode (EC0): Produced in the same manner as in Example 5 of Negative Electrode, except that barium strontium titanate was not added.

[0087] Example: Fabrication of a Triboelectric Negative Electrode Layer (Molybdenum Sulfide) Negative electrode example 8 (EC 0.2): Molybdenum sulfide (diameter 90 nm) was prepared by Sigma-Aldrich, and silicone rubber was Ecoflex by Smooth-On. TM-00-30 was prepared. P-60 sandpaper was prepared to roughen the surface of the tribo-charged negative electrode layer. 0.2 g of molybdenum sulfide was mixed with 10 g of silicone rubber containing components A and B and thoroughly stirred to produce a mixture. The mixture was then poured onto the sandpaper and sanded using a doctor blade to a thickness of 230 ± 5 μm, after which it was dried at room temperature (20 to 25°C) for 8 hours. This produced a tribo-charged negative electrode layer containing 0.2 parts by weight of molybdenum sulfide per 100 parts by weight of silicone rubber.

[0088] Negative Electrode Example 9 (EC 0.5): This was prepared in the same manner as Negative Electrode Example 8, except that 0.05 g of molybdenum sulfide was added to prepare a triboelectrically charged negative electrode layer containing 0.5 parts by weight of molybdenum sulfide per 100 parts by weight of silicone rubber.

[0089] Negative Electrode Example 10 (EC1): EC1 was prepared in the same manner as Negative Electrode Example 8, except that 0.10 g of molybdenum sulfide was added to prepare a triboelectrically charged negative electrode layer containing 1.0 part by weight of molybdenum sulfide per 100 parts by weight of silicone rubber.

[0090] Negative Electrode Example 11 (EC1.5): This was prepared in the same manner as Negative Electrode Example 8, except that 0.15 g of molybdenum sulfide was added to prepare a triboelectrically charged negative electrode layer containing 1.5 parts by weight of molybdenum sulfide per 100 parts by weight of silicone rubber.

[0091] Negative Electrode Example 12: This was prepared in the same manner as Negative Electrode Example 8, except that 0.20 g of molybdenum sulfide was added to prepare a triboelectrically charged negative electrode layer containing 2.0 parts by weight of molybdenum sulfide per 100 parts by weight of silicone rubber. This example was not cured. Comparative Example 3 Negative Electrode (ECO): The negative electrode was prepared in the same manner as in Example 8, except that molybdenum sulfide was not added.

[0092] Example: Fabrication of triboelectric nanogenerators Triboelectric nanogenerators were fabricated by combining the previously fabricated Examples and Comparative Examples. First, the triboelectrically charged positive electrode layers of the negative electrode Examples and Comparative Examples were cut to 5 cm x 5 cm, and one side was attached to one side of an Al electrode of the same size. The triboelectrically charged positive electrode layers of the positive electrode Examples and Comparative Examples were also cut to 5 cm x 5 cm, and one side was attached to one side of an Al electrode of the same size. An 8 mm long spacer was placed between the other side of the triboelectrically charged negative electrode layer and the other side of the triboelectrically charged positive electrode layer, and then the other sides of each electrode were positioned facing the spacer. Two 5 cm x 5 cm acrylic plates were attached to the other side of each Al electrode. The overall shape is shown in Figure 1. When pressure was applied to the acrylic plates, the triboelectrically charged positive electrode layer and the triboelectrically charged negative electrode layer came into contact with each other.

[0093] Experimental example: Naked eye observation Negative electrode Examples 1 to 4 and negative electrode Comparative Example 1 were visually observed. In the case of negative electrode Example 4, the fluorine-functionalized graphite content was excessive and the material was not sufficiently hardened, so it could not be used as a triboelectrically charged negative electrode layer.

[0094] Experimental example: SME analysis This analysis was performed using a scanning electron microscope (SEM, JEOL Ltd. JSM-6510) at 15 kV. Figure 2 shows SEM photographs of reduced graphene oxide functionalized with tetraethylenepentamine, positive electrode comparative example 1, and positive electrode examples 1 to 4. Figure 4 shows SEM photographs of negative electrode example 3. Figures 9(a) and 9(b) show SEM photographs of negative electrode examples 5 and 7, respectively. Figures 12(a) and 12(b) show SEM photographs of negative electrode example 11 and negative electrode comparative example 3, respectively.

[0095] Referring to FIG. 2, it can be seen that agglomerates were observed on the surface of positive electrode Examples 3 (PUAFG05) and 4 (PUAFGO10), which contained 5 parts by weight or more of reduced graphene oxide functionalized with tetraethylenepentamine.

[0096] Experimental example: EDS analysis The surface elements of the examples and comparative examples were analyzed using an EDS device.

[0097] Table 1 shows the analysis results of the reduced graphene oxide functionalized with tetraethylenepentamine, the positive electrode example, and the positive electrode comparative example. Table 1 shows that the measured value of N element increases as the content of the reduced graphene oxide functionalized with tetraethylenepentamine increases.

[0098] [Table 1]

[0099] Figure 5 shows the analytical results for negative electrode example 3, and Table 2 shows the analytical results for fluorine-functionalized graphite and negative electrode examples 1 to 4. Table 5 shows that elements Si, O, C, and F were observed. Table 2 also shows that the measured value of F element significantly increased as the content of fluorine-functionalized graphite increased.

[0100] [Table 2]

[0101] Experimental example: XRD analysis XRD analysis was carried out using CuKα under conditions of 40 kV and 30 mA.

[0102] Figures 3(a), (b), and (c) show the XRD analysis results for cathode Comparative Example 1, reduced graphene oxide functionalized with tetraethylenepentamine, and cathode Example 4, respectively. Figure 3(c) is a representation using Gaussian multiple peak fitting in Origin software. Referring to Figure 3, it can be seen that peaks for both polyurethane and reduced graphene oxide functionalized with tetraethylenepentamine are observed in cathode Example 4.

[0103] Figure 6(a), (b), and (c) show the silicone rubber (Ecoflex TM6(c) shows the XRD analysis results of the silicone rubber (-00-30), fluorine-functionalized graphite, and anode Example 3. Figure 6(c) shows the results of the XRD analysis using Gaussian multi-peak fitting in Origin software. Referring to Figure 6, it can be seen that peaks of both the silicone rubber and fluorine-functionalized graphite are observed in anode Example 3.

[0104] 10 shows the XRD analysis results of Negative Electrode Examples 5 to 7 and Negative Electrode Comparative Example 2. Referring to FIG. 10, it can be seen that peaks specific to barium strontium titanate are observed in Negative Electrode Examples 5 to 7.

[0105] Fig. 13 shows the XRD analysis results of negative electrode Examples 8 to 11. Referring to Fig. 13, it can be seen that peaks specific to molybdenum sulfide are observed in negative electrode Examples 8 to 11.

[0106] Experimental example: Measurement of dielectric constant and dielectric loss The dielectric constant and dielectric loss were measured using an impedance / gain-phase analyzer (SI-1260, Solartron Analytical Co., UK) at 25°C and a relative humidity of 41%.

[0107] 7(a) and (b) show the dielectric constant and dielectric loss measurement results for negative electrode Examples 1 to 3 and negative electrode Comparative Example 1, respectively. Referring to Fig. 7, it can be seen that the dielectric constant increased with an increase in the content of fluorine-functionalized graphite, but the change in dielectric loss was not significant. In other words, it was demonstrated that negative electrode Example 3, which contains 15 parts by weight of fluorine-functionalized graphite, was able to improve the dielectric constant without affecting the dielectric loss.

[0108] 11(a) and 11(b) show the dielectric constant and dielectric loss measurement results for Negative Electrode Examples 5 to 7 and Negative Electrode Comparative Example 2, respectively. Referring to Fig. 11, it can be seen that the dielectric constant increased with an increase in the content of barium strontium titanate, but the change in dielectric loss was not significant. This indicates that the addition of barium strontium titanate can improve the dielectric constant without affecting the dielectric loss.

[0109] 14(a) and 14(b) show the dielectric constant and dielectric loss measurement results for Negative Electrode Examples 8 to 11 and Negative Electrode Comparative Example 3, respectively. Referring to Fig. 14, it can be seen that the dielectric constant increased with increasing molybdenum sulfide content, but the change in dielectric loss was not significant. This indicates that the addition of molybdenum sulfide improves the dielectric constant without affecting the dielectric loss.

[0110] Experimental example: Measurement of surface potential The surface potential was measured using a Kelvin probe force microscope (KPFM; NX10, Park Systems) in non-contact mode.

[0111] Figure 8 shows the results of measuring the surface potential over time for Negative Electrode Examples 1 to 3 and Negative Electrode Comparative Example 1. Referring to Figure 8, it can be seen that the surface potential decreases significantly over the first 10 hours and then converges to a constant level. After 40 hours, the surface potential of Negative Electrode Example 4 decreases 19 times, from -848 V to -43 V, while that of Negative Electrode Example 3 decreases 5 times, from -1813 V to -346 V, demonstrating that Negative Electrode Example 3 has superior performance.

[0112] Experimental example: Measurement of the electrical properties of a triboelectric nanogenerator Using a triboelectric nanogenerator fabricated by combining the previously fabricated triboelectric negative electrode layer and triboelectric positive electrode layer, V OC , I SC To measure the voltage, an oscilloscope (TBS2204B, Tektronix), a low-noise current amplifier (DLPCA-200, Femto), and an electrometer (6514, Keithley) were used.

[0113] Fig. 15(a) shows the measurement values ​​of a triboelectric nanogenerator combining anode comparative example 1, cathode examples 1 to 4, and cathode comparative example 1, Fig. 15(b) shows anode example 1, cathode examples 1 to 4, and cathode comparative example 1, Fig. 15(c) shows anode example 2, cathode examples 1 to 4, and cathode comparative example 1, and Fig. 15(d) shows anode example 3, cathode examples 1 to 4, and cathode comparative example 1. Referring to Fig. 15, it can be seen that cathode example 2, which contains 2 parts by weight of reduced graphene oxide functionalized with tetraethylenepentamine, exhibits the best electrical properties, and that deviations from this range result in decreased electrical properties.

[0114] 17(a) to 17(c) show the measurement results of VOC, ISC, and Q for the triboelectric nanogenerators in which positive electrode Examples 1 to 3 and positive electrode Comparative Example 1 are combined with negative electrode Examples 5 to 7 and negative electrode Comparative Example 2, respectively. Referring to FIG. 17(a), when combined with positive electrode Example 2, VOC, ISC, and Q increased as the content of barium strontium titanate increased from 0 to 7.5 parts by weight. OC The voltage increased from 161V to 257V, but at 10 parts by weight, which is more than 7.5 parts by weight, it decreased to 130V. SC A similar result was observed (see FIG. 17(b)). This indicates that the current density decreases when the content of barium strontium titanate deviates from a specific value.

[0115] 19 shows the measurement results of VOC and ISC of the triboelectric nanogenerators in combination with positive electrode example 2, negative electrode examples 8 to 11, and negative electrode comparative example 3. Referring to FIG. 19, when combined with positive electrode example 2, the VOC and ISC decreased as the molybdenum sulfide content increased from 0 to 1.5 parts by weight. OC has increased from 297.4V to 451V, and I SC The Cr content also increased with increasing molybdenum sulfide content, and in particular, high values ​​were observed in negative electrode Examples 10 and 11, which contained 1.0 part by weight or more of molybdenum sulfide.

[0116] Experimental example: Measurement of electrical characteristics of triboelectric nanogenerators due to load pressure V when applying loads from 0.3 to 10 N to a triboelectric nanogenerator OC , I SC The change in was measured.

[0117] Fig. 16 shows the measurement results of the electrical characteristics as a function of load in the triboelectric nanogenerator combined with positive electrode example 2 and negative electrode example 3. Referring to Fig. 16, it can be seen that the output is improved by the load, and particularly high output is shown at a pressure of 6 N or more.

[0118] 18 shows the measurement results of the electrical characteristics depending on the load in the triboelectric nanogenerator in which the positive electrode example 2 and the negative electrode example 5 are combined. Referring to FIG. 18, it can be seen that the output is improved depending on the load.

[0119] 20 shows the measurement results of the electrical characteristics depending on the load in the triboelectric nanogenerator that combines the positive electrode example 2 and the negative electrode example 11. Referring to FIG. 20, it can be seen that the output is improved depending on the load.

Claims

1. The composite material comprises a reduced graphene oxide functionalized with tetraethylenepentamine (rGO-TEPA) and a first polymer; Triboelectric positive electrode compositions for triboelectric nanogenerators.

2. The content of the reduced graphene oxide functionalized with tetraethylenepentamine is 1 to 10 parts by weight based on 100 parts by weight of the first polymer.

10. The triboelectric positive electrode composition for a triboelectric nanogenerator of claim 1.

3. Fluorine-functionalized graphite, perovskite materials, and molybdenum sulfide (MoS) ２ ) and a second polymer, Triboelectric negative electrode compositions for triboelectric nanogenerators.

4. The content of the fluorine-functionalized graphite is 5 to 15 parts by weight based on 100 parts by weight of the second polymer, The content of the perovskite material is 5 to 10 parts by weight based on 100 parts by weight of the second polymer; The content of the molybdenum sulfide is 0.2 to 2.0 parts by weight based on 100 parts by weight of the second polymer. The triboelectric negative electrode composition for a triboelectric nanogenerator according to claim 3.

5. The perovskite material is barium strontium titanate. The triboelectric negative electrode composition for a triboelectric nanogenerator according to claim 3.

6. a tribo-positive layer and a tribo-negative layer; the triboelectric positive electrode layer comprises reduced graphene oxide functionalized with tetraethylenepentamine (rGO-TEPA) and a first polymer; The triboelectric anode layer is made of fluorine-functionalized graphite, perovskite materials, and molybdenum sulfide (MoS). ２ ) and a second polymer, Triboelectric nanogenerator.

7. The triboelectrically charged positive electrode layer is manufactured by an electrodischarge method using a first mixture in which the reduced graphene oxide functionalized with tetraethylenepentamine and a first polymer are mixed. The triboelectric nanogenerator of claim 6 .

8. The triboelectric negative electrode layer is a composite of the fluorine-functionalized graphite, perovskite material, and molybdenum sulfide (MoS). ２ ) and a second polymer, and the second mixture is mixed with the second polymer, and the second mixture is produced by a casting method. The triboelectric nanogenerator of claim 6 .

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