WO2017078301A1 - Method of preparing triboelectric film with intagliated, embossed or dual embossed pattern, triboelectric film prepared thereby, and high-performance triboelectric nanogenerator comprising same - Google Patents

Abstract

The present invention relates to a method for preparing a triboelectric film having an intagliated, embossed or dual embossed pattern on the basis of a colloid single-layer film formed by forced assembly on a substrate, a triboelectric film prepared thereby, and a high-performance triboelectric nanogenerator comprising the same. When applying a triboelectric film having an intagliated, embossed or dual embossed pattern prepared by the preparation method of the present invention to a triboelectric nanogenerator, it is possible to achieve not only excellent electrical performances, but also moisture resistance and high mechanical stability in a large scale.

Description

Method for producing triboelectric film having intaglio, embossed or double-embossed pattern, triboelectric film produced thereby and high performance triboelectric element comprising the same

The present invention relates to a method of manufacturing a triboelectric film having an intaglio, an embossed or a double embossed pattern, a triboelectric film produced thereby and a high performance triboelectric device comprising the same.

Recently, due to the rapid expansion and development of the use of various wireless electronic devices, there is a demand for a sustainable, renewable, maintenance-free energy source. Self-power generation is of great interest as an energy source that meets the needs of modern societies for ecological problems and the reduction of fossil fuel use.

Among various types of self-generators using light, heat, and mechanical forces, triboelectric nanogenerators (TENGs) are receiving considerable attention as notable alternatives to energy production and renewable resources in the field of green nanotechnology. TENGs can effectively convert readily available mechanical energy into sustainable electrical energy from various irregular sources that exist around our daily lives.

TENGs uses the generated triboelectric charge as a charge drive source for current generation. When the surfaces of the electron donor and acceptor materials are periodically contacted and separated, the generation and movement of an electrostatic charge causes a potential difference between the electrodes that can cause the flow of electrons through an external circuit. While much research is being done to improve the electrical performance of TENGs, these studies are mainly focused on the selection of triboelectric materials and the periodic switching of contact / dissociation.

Relatively, however, studies on frictional electrification, device stability in wet environments, and control of surface morphology, which have a significant effect on charge generation, are poorly studied. Recently, photolithography based on Si-molded (F.-R. Fan, L. Lin, G. Zhu, W. Wu, R. Zhang, ZL Wang, Nano Lett . 2012 , 12 , 3109.) and electrodeposition processes (G. Zhu, C. Pan, W. Guo, CY Chen, Y. Zhou, R. Yu, ZL Wang, Nano Lett . 2012 , 12 , 4960.) TENGs of micropatterns have been reported to improve the electrical performance by increasing the contact area between two different friction plates. In addition, various self-assembly processes (ex: solvent evaporation method (KY Lee, J. Chun, J.-H. Lee, KN Kim, N.-R. Kang, J.-Y. Kim, MH Kim, K.- S. Shin, MK Gupta, JM Baik, S.-W. Kim, Adv . Mater. 2014 , 29 , 5037.), selective etching of spontaneous block copolymer templates (CK Jeong, KM Baek, S. Niu, TW Nam) , YH Hur, DY Park, G.-T. Hwang, M. Byun, ZL Wang, YS Jung, KJ Lee, Nano Lett . 2014 , 14 , 7031.), self-assembly of nanoparticles (G. Zhu, Z.-H. Lin, Q. Jing, P. Bai, C. Pan, Y. Yang, Y. Zhou, ZL Wang, Nano Lett . 2013 , 13 , 847., Z.-H. Lin, G. Zhu, YS Zhou, Y. Yang, P. Bai, J. Chen, ZL Wang, Angew . Chem . Int . Ed. 2013 , 52 , 5065.) have been reported to improve the electrical output of TENGs using triboelectric films with micro or nanostructures. However, the above-described methods require relatively complex and delicate processing over a small area, and when applied to large-area TENGs, there are problems in terms of implementation of practical and reproducible design structures, maintenance of mechanical stability, and manufacturing cost. . In this regard, the development of TENGs that can control the expansion of the size, can be manufactured efficiently and has moisture resistance, mechanical stability and high electrical performance is urgently needed.

The present invention has been made to solve the above-mentioned problems, the present invention is to provide a method of manufacturing a triboelectric film formed in an intaglio, embossed or double-embossed pattern, based on the colloidal monolayer film formed through a forced assembly on the substrate. .

In addition, the present invention is to provide a high-performance triboelectric device exhibiting high electrical performance, moisture resistance and mechanical stability by applying the triboelectric film formed in the intaglio, embossed or double-embossed pattern to the triboelectric device.

The present invention to solve the above problems,

(a) spin coating a mixture of a prepolymer of polydimethylsiloxane and a crosslinking agent onto a silicon wafer to form a plurality of polydimethylsiloxane substrates; (b) placing negatively charged colloidal particles on a first polydimethylsiloxane substrate of the plurality of polydimethylsiloxane substrates, and then rubbing to a second polydimethylsiloxane substrate of the plurality of polydimethylsiloxane substrates. Forming a colloidal monolayer film in which the colloidal particles are arranged on the second polydimethylsiloxane substrate; And (c) preparing a negative pattern triboelectric film by pouring and curing a mixture of a prepolymer of polydimethylsiloxane and a crosslinking agent on the second polydimethylsiloxane substrate on which the colloidal monolayer film is formed. It provides a method for producing an electrical film.

In this case, the intaglio pattern triboelectric film may have a intaglio pattern including a plurality of dome-shaped recesses recessed in one surface.

According to a preferred embodiment of the present invention, the diameter of the colloidal particles may be 0.1 to 10 ㎛.

In addition, the manufacturing method according to the present invention comprises the steps of peeling the intaglio pattern triboelectric film of step (c) from the second polydimethylsiloxane substrate; And preparing a relief pattern triboelectric film by pouring and curing a mixture of a prepolymer of polydimethylsiloxane and a crosslinking agent on the exfoliated intaglio pattern triboelectric film.

In this case, the embossed pattern triboelectric film may have an embossed pattern including a plurality of dome-shaped convex parts protruding convexly on one surface thereof.

In addition, the manufacturing method according to the present invention comprises the steps of depositing colloidal particles having a smaller diameter than the colloidal particles on the colloidal particles between the step (b) and (c) when the bivalent pattern triboelectric film is manufactured It may further include;

At this time, the embossed triboelectric film has a plurality of dome-shaped first convex portions projecting convexly on one surface and a plurality of second convex portions smaller in size than the first convex portion on the first convex portion. The double-embossed pattern may be formed.

According to a preferred embodiment of the present invention, the diameter of the deposited colloidal particles may be 0.03 to 3 ㎛.

In addition, the manufacturing method according to the present invention, after manufacturing the embossed pattern triboelectric film, trichloroperfluorooctylsilane (trichloro (1H, 1H, 2H, 2H-perfluorooctyl) silane), purple on the surface of the embossed pattern triboelectric film Fluorosilane organic material selected from the group consisting of urooctyltriethoxysilane (1H, 1H, 2H, 2H-perfluorotriethoxysilane), perfluorodecyltriethoxysilane (1H, 1H, 2H, 2H-perfluorodecyl-triethoxysilane) The step of modifying the surface of the embossed triboelectric film by hydrophobic treatment may be further included.

In addition, the present invention provides a triboelectric film and a triboelectric element including the same produced according to the manufacturing method.

The triboelectric film having the intaglio, embossed, or double-embossed pattern prepared according to the manufacturing method of the present invention has not only excellent electrical performance but also high moisture resistance and high mechanical stability in large scale. Can be.

1 is a view schematically showing a manufacturing process of the intaglio and embossed pattern triboelectric film according to the present invention. The intaglio pattern triboelectric film (IV) and the embossed pattern triboelectric film (VI) according to the present invention were made of a substrate (II) on which a polystyrene colloidal monolayer film was formed and an intaglio pattern triboelectric film (IV) as a template.

FIG. 2 is a photograph and SEM image of a PS colloidal monolayer film in which 1, 2, and 5 mm diameter PS colloidal particles formed on a 4-inch silicon wafer are arranged in hexagonally-packed form.

Figure 3 is a photograph and SEM image of the negative pattern PDMS triboelectric film prepared from a substrate coated with 1, 2, 5 mm PS monolayer.

4 is an SEM image of the inclined cross section of an embossed pattern PDMS triboelectric film.

5 is a view schematically showing the structure of the triboelectric element FTENG based on the intaglio and embossed triboelectric film.

FIG. 6 is a graph showing output voltages with time of a flat triboelectric element (Flat-TENG) and a 5 μm engraved triboelectric element (5 μm-intaglio-FTENG).

FIG. 7 is a graph showing the current density over time of the planar triboelectric element (Flat-TENG) and the 5-μm negative-angle triboelectric element (5 μm-intaglio-FTENG).

8 shows the results of the polarity conversion test for the output voltage (a) and current density (b) of 5 mm -intanglio-FTENG. When the voltage and current meter was connected to the first 5 mm -intanglio-FTENG, both pulses were recorded primarily during pushing. When the voltage and current meters were connected to reverse polarity, the pulses were also recorded in reverse. However, the magnitudes of the output voltage and current were almost the same under both conditions.

9 is a schematic representation of the electrical energy generation mechanism of FTENGs. (a) shows the initial position without mechanical compressive force, (b) shows the contact between the upper contact electrode and the PDMS film under compressive force, and (c) shows between the upper contact electrode and the PDMS film after the external force is removed. (D) represents the return of the separated distance to the initial position. (e) shows the decrease in separation distance when the compressive force is applied again. More specifically, when the two triboelectric plates (contact electrode and PDMS film) are first separated by the initial distance d ₀ , the surface is contacted by external compressive force, and electrons are injected from the contact electrode (strong electrons). Donation) and transfer to the PDMS film (strong electronic fixation), which results in the generation of surface triboelectric charges. However, if the separated distance increases due to the release of the compressed spring (return to d ₀ ), the separated charge is directed to the contact electrode to generate an electric field. This leads to a high potential at the contact electrode, which generates electrons flowing at the back electrode and eliminates the generation of the triboelectrically induced potential. When the gap between the two plates returns to the initial distance d ₀ , the positive triboelectric charge of the Al contact electrode is completely blocked, leading to the same amount of positive charge at the back Al electrode. However, when the separated distance is once again reduced by the compressive force, the potential difference of reverse polarity returns again. This causes a reverse flow of the charge (ie, a negative current) to neutralize the positive triboelectric charge at the bottom Al electrode.

Fig. 10 shows the change of the output voltage according to the size of the recess of the intanglio-FTENGs under the given compressive force.

FIG. 11 shows the change in output current according to the size (0.9, 1.9, 4.8 μm) of the recess of intanglio-FTENGs, under a compressive force of 10 to 90 N. FIG.

Fig. 12 shows the change of the output voltage according to the size of the convex portion of the embossed triboelectric elements (embossed-FTENGs).

Figure 13 shows the variation of the output current with the size of the embossed-FTENGs convex portion.

FIG. 14 is a view schematically illustrating a manufacturing process of a PDMS triboelectric film having a dual embossed pattern.

15 is an FE-SEM image of a dual-embossed PDMS triboelectric film.

16 shows the output voltages of Flat-TENG, 1 μm, 2 μm embossed-FTENGs and dual embossed-FTENGs.

FIG. 17 shows current densities of Flat-TENG, 1, 2, 5 μm embossed-FTENGs and dual embossed-FTENGs under a compression force of 90 N. FIG.

18 shows the electrical stability test results of dual embossed-FTENGs at 20% relative humidity.

FIG. 19 shows simulation results for the triboelectric potential difference of Flat, 1 μm embossed and dual embossed PDMS triboelectric films using COMSOL multiphysics software under the same compressive force. As a result of the measurement, it was confirmed that the dual embossed PDMS triboelectric film exhibited the largest potential difference.

20 shows water contact angles of Flat, 1 μm, 2 μm embossed and dual embossed PDMS triboelectric films.

Figure 21 shows the effect of relative humidity on the output voltage of Flat-TENG and FTENG according to the present invention. At this time, a cyclic compression force of 90 N was used for the triboelectric measurement.

FIG. 22 is a diagram illustrating a process of lighting 50 LEDs using electric energy generated by dual embossed-FTENGs.

Hereinafter, the present invention will be described in more detail.

In the present invention, based on the colloidal monolayer film formed through a forced assembly on the substrate, to provide a method of manufacturing a triboelectric film formed with an intaglio, embossed or double-embossed pattern. In addition, the present invention is to apply a triboelectric film to the triboelectric device, to provide a high-performance triboelectric device exhibiting high electrical performance, moisture resistance and mechanical stability.

To this end, in the present invention, a method of manufacturing a triboelectric film in which an intaglio, embossed or double-embossed pattern is formed by using a substrate coated with a colloidal monolayer film formed using a force assembly of colloidal particles based on mechanical friction is provided. to provide.

As shown in FIG. 1, a method of manufacturing a triboelectric film according to the present invention includes the following steps.

(a) spin coating a mixture of a prepolymer of polydimethylsiloxane and a crosslinking agent onto a silicon wafer to form a plurality of polydimethylsiloxane substrates;

(b) placing negatively charged colloidal particles on a first polydimethylsiloxane substrate of the plurality of polydimethylsiloxane substrates, and then rubbing to a second polydimethylsiloxane substrate of the plurality of polydimethylsiloxane substrates. Forming a colloidal monolayer film in which the colloidal particles are arranged on the second polydimethylsiloxane substrate; And

(c) preparing a negative pattern triboelectric film by pouring and curing a mixture of a prepolymer of polydimethylsiloxane and a crosslinking agent on the second polydimethylsiloxane substrate on which the colloidal monolayer film is formed;

Specifically, the steps (a) and (b) is to prepare a mold for manufacturing a triboelectric film having an intaglio, embossed or double-embossed pattern, polydimethylsiloxane through the steps (a) and (b) Colloidal particles are forcibly assembled on the substrate to form a colloidal monolayer film. In order to form such a monolayer film, colloidal powder was placed on one of the substrates as described in step (b), and then mechanically rubbed the colloidal particles onto the other substrate. As the colloidal particles move to the other substrate, they are densely arranged on the substrate in a hexagonal dense structure through forced assembly to form a colloidal monolayer (FIG. 2). In this case, the colloidal particles are preferably polystyrene (PS) or silica (Si) colloidal particles.

The polydimethylsiloxane substrate on which the colloidal monolayer film is formed is used as a mold for the production of the intaglio pattern triboelectric film. As described in step (c), the polydimethylsiloxane substrate is formed by pouring and curing a mixture of the prepolymer and the crosslinking agent of the polydimethylsiloxane. A triboelectric film is produced. The intaglio pattern triboelectric film is peeled from the mold and used as a triboelectric film, wherein the intaglio pattern triboelectric film corresponds to the surface shape of colloidal particles forming the colloidal monolayer film, and is concave recessed in one surface of the film. An intaglio pattern including a plurality of parts is formed, and as shown in FIG. 3, the intaglio pattern triboelectric PDMS film is perfectly replicated without remaining PS colloids on the polydimethylsiloxane substrate on which the colloidal monolayer film is used as a template, and has a hexagonal dense structure. It will form an intaglio pattern of.

At this time, the diameter of the concave portion provided on the intaglio pattern is determined by the diameter of the colloidal particles forming the colloidal monolayer film, as can be seen from the results of the following examples, the diameter of the colloidal particles is 0.1 to 10 ㎛ It is preferable.

In addition, the diameter of the concave portion provided on the intaglio pattern is slightly reduced than the diameter of the colloidal particles due to shrinkage of the cross-linked polydimethylsiloxane (PDMS) in the pattern formation process, specifically, shown in Figure 3 below As shown, when the diameter of the colloidal particles is 1, 2, 5 ㎛ it can be seen that the diameter of the recess is reduced to about 0.9, 1.9, 4.8 ㎛.

The produced intaglio pattern triboelectric film is used as a mold for the manufacture of the embossed pattern triboelectric film, specifically, the embossed pattern triboelectric film is a second polydimethylsiloxane substrate to the intaglio pattern triboelectric film of step (c) Exfoliating from; And preparing a relief pattern triboelectric film by pouring and curing a mixture of a prepolymer of polydimethylsiloxane and a crosslinking agent on the exfoliated negative pattern triboelectric film.

The embossed pattern triboelectric film is peeled from the mold and used as a triboelectric film. The embossed pattern triboelectric film corresponds to a surface shape of a recess of the intaglio pattern triboelectric film, protruding convexly on one surface of the film. An embossed pattern including a plurality of convex portions is formed.

At this time, the diameter of the convex portion provided on the embossed pattern is determined by the diameter of the concave portion, and as described in the diameter of the concave portion, due to the shrinkage of the crosslinked polydimethylsiloxane (PDMS) in the pattern formation process The diameter of the concave portion is slightly reduced, specifically, as shown in FIG. 4, when the diameter of the colloidal particles is 1, 2, and 5 μm, the diameter of the convex portion decreases to about 0.8, 1.8, and 4.6 μm. have.

In addition, the present invention provides a triboelectric film formed with a double-embossed pattern in which an additional nano-projection is integrally implemented in the convex portion of the embossed pattern, which is the colloidal particle phase between the steps (b) and (c) Preparing colloidal particles having a diameter smaller than that of the colloidal particles; After such a deposition process, when the intaglio pattern and the embossed pattern triboelectric manufacturing method described above are followed, a double embossed pattern is formed on one surface of the triboelectric film. Specifically, the double embossed pattern is formed on one surface of the triboelectric film. And a plurality of first convex portions having a convexly protruding dome shape and a plurality of second convex portions smaller in size than the first convex portion on the first convex portion.

At this time, if the diameter of the colloidal particles deposited is smaller than the diameter of the colloidal particles forming the colloidal monolayer, it is not limited thereto, but preferably has a diameter of 0.03 to 3 ㎛.

In addition, the present invention is trichloro perfluoro octyl silane (trichloro (1H, 1H, 2H, 2H-perfluorooctyl) silane), perfluorooctyl trier on the surface of the triboelectric film to enhance the moisture resistance of the triboelectric film Embossed pattern by treating a fluorine silane-based organic material selected from the group consisting of oxysilane (1H, 1H, 2H, 2H-perfluorotriethoxysilane), perfluorodecyltriethoxysilane (1H, 1H, 2H, 2H-perfluorodecyl-triethoxysilane) The method may further include hydrophobic modification of the surface of the triboelectric film.

In addition, the present invention provides a triboelectric element comprising a triboelectric film produced through the manufacturing method, the triboelectric element (FTENGs) according to the present invention, as shown in Figure 5 below, aluminum plate and bone It consists of a triboelectric film (15 mm x 15 mm) according to the invention, wherein the aluminum plate is used as contact electrode and bipolar triboelectric material. In addition, one side of the polyacrylate film is bonded to the triboelectric film according to the invention having a negative electrode triboelectric properties, the other side of the polyacrylate is attached to the aluminum electrode. At this time, four springs are attached to the edges of the polyacrylate film so that the aluminum electrode and the triboelectric film have a predetermined interval for efficient contact and separation of the triboelectric plate (aluminum electrode and triboelectric film).

The electrical performance of the triboelectric element depends on the contact area and the morphological characteristics of the triboelectric film, and the triboelectric film according to the present invention is manufactured using a colloidal monolayer film in which colloids are forcibly assembled to control the diameter of the colloid. By adjusting the shape of the intaglio, embossed pattern, by adjusting the pattern can improve the electrical performance of the triboelectric element. In addition, the triboelectric film according to the present invention has improved the hydrophobicity of the surface through the hydrophobic modification step, as can be seen from the results of the following examples can maintain a high electrical output level in a wide humidity range, in addition to this The double-embossed triboelectric film according to the present invention is embodied on a substrate with convex portions of different sizes integrally, so that its performance can be maintained without electrical deterioration for a long time as can be seen from the results of the following examples.

In conclusion, the manufacturing method according to the present invention can provide a large-area triboelectric element having high performance regardless of the size and shape of the substrate, high reproducibility and cost-effectively.

Hereinafter, the present invention will be described in more detail with reference to preferred embodiments. However, these examples and the like are intended to explain the present invention in more detail, and it will be apparent to those skilled in the art that the scope of the present invention is not limited thereto.

material

Dimethylsiloxane, PDMS (Sylgard), and PS colloids having a diameter of 0.6, 1, 2, and 5 μm used in the present invention were purchased from Sigma-Aldrich, Dow Corning, and Microparticles GmbH, respectively.

Example. Preparation of triboelectric film according to the present invention

Preparation of PDMS Substrate with Colloidal Monolayer

The polydimethylsiloxane (PDMS) prepolymer and the crosslinker were mixed in a weight ratio of 10: 1 and stirred for 30 minutes. After the mixture was spin coated on the Si wafer at 3000 rpm for 30 seconds, the formed PDMS coated substrate was cured at 80 ° C. for 5 hours. After the curing process, negatively charged 1, 2, 5 μm diameter polystyrene (PS) colloidal dry powders were placed on PDMS coated Si wafers and then mechanically rubbed onto other PDMS coated substrates. Through this forced assembly process, a colloidal monolayer film in which the colloids are arranged in a hexagonal dense structure on the PDMS substrate was formed.

Fabrication of intaglio pattern triboelectric film

A PDMS prepolymer mixture (PDMS prepolymer: crosslinking agent = 10: 1, w / w) was poured onto the PDMS substrate on which the PS colloidal monolayer was formed and thermally cured at 150 ° C. for 40 minutes. The cured PDMS film was peeled from the PDMS template, and then immersed in acetone for 24 hours to completely remove the remaining PS colloid on the separated PDMS surface. intanglio-PDMS) was prepared.

Fabrication of Embossed Pattern Triboelectric Film

Embossed PDMS triboelectric film (embossed-PDMS film) was prepared using intanglio-PDMS as a template. First, trichloro (1H, 1H, 2H, 2H-perfluorooctyl) silane was coated on intanglio-PDMS, and then a PDMS prepolymer mixture (PDMS prepolymer crosslinking agent = 10: 1, w / w) was poured onto the intanglio-PDMS surface, Heat cured at 150 ° C. for 40 minutes. The cured PDMS film was peeled from the PDMS template and then immersed in acetone for 24 hours to completely remove the PS colloid remaining on the separated PDMS surface to prepare an embossed PDMS embossed-PDMS film.

Fabrication of triboelectric film with a double relief pattern

PS-colloid monolayer (diameter ~ 2 mm) negatively charged with cationic polyethyleneimine (PEI) to produce a double embossed PDMS film with a double-embossed pattern ) Was electrostatically adsorbed onto the coated substrate. Next, a negatively charged PS colloid (concentration of the PS colloidal solution of ˜1 wt%) of approximately 607 nm diameter was deposited on a PEI coated substrate on an aqueous solvent. The formed substrate was soaked in water for 5 minutes to remove the weakly bound PS colloid and then dried in vacuo for 2 hours. Next, a dual embossed PDMS film was manufactured through the same process as the above-described method of manufacturing the intaglio and embossed pattern triboelectric film. In order to form a hydrophobic surface of the triboelectric film, trichloro ( 1H, 1H, 2H, 2H-perfluorooctyl) silane was treated.

Test example. Performance test of triboelectric film and triboelectric element according to the present invention

First, in order to compare the performance with the triboelectric film and the triboelectric device according to the present invention, a flat PDMS triboelectric film (Flat PDMS) and a triboelectric device (Flat-TENG) having no pattern were used as comparative examples.

Surface morphology of intanglio-PDMS, embossed-PDMS, Dual embossed-PDMS according to the present invention was measured using a field emission scanning electron microscope (FE-SEM) (Hitachi Inc., model: Hitachi S-4800). A pushing tester (Labworks Inc., model: ET-126-1) was used to create a vertical compressive strain of FTENG with a distance of 450 μm between the top and bottom electrodes and a contact area of 1.5 cm × 1.5. In addition, electrical performance was measured using a Tektronix DMO 3052 Digital Phosphor Oscilloscope and a low-noise current preamplifier (Stanford Research Systems, Inc. model: SR570).

FIG. 6 is a graph showing output voltage and current density of a planar triboelectric element (Flat-TENG) and a 5 μm engraved triboelectric element (5 μm-intaglio-FTENG) with time. For Flat-TENG, the electrical outputs were approximately 57 V and 33 mA · m ⁻² . However, under the same mechanical force, the output voltage and current density of the 5 mm -intaglio-FTENGs according to the invention were measured very high, approximately 103 V and 48 mA · m ⁻² . These high output voltages and current densities were derived from periodic contact and separation between the contact electrode and PDMS through the polarity switching test shown in FIG. 8 (FIG. 8).

Given that the electrical energy generation of Flat-TENG and 5 μm-intaglio-FTENGs is due to the coupling of the triboelectric effect and electrostatic induction (FIG. 9), the improved electrical output of 5 μm-intaglio-FTENGs under the same mechanical force, The surface area means that intanglio-PDMS generates more triboelectric charges than flat-PDMS. The intaglio pattern structure may interfere with contact between the electrode and the PDMS plate, but may cause deformation of the intaglio pattern PDMS triboelectric film under high compressive force to provide a larger contact area between the two plates. In addition to this increase in contact area, electrostatic induction can contribute to the generation of triboelectric charges in the non-contact region.

Next, the output voltage and the current density according to the size and the compressive force of the concave portion of the intanglio-PDMS (1.5 cm x 1.5 cm) were measured (Figs. 10 and 11). As a result of the measurement, the size of the recess is reduced to about 0.9 μm (from 1 μm intaglio-FTENG), and as the compressive force increases from 10 to 90 N, the output voltage and current density become very large, 170 V and 103 mA · m ⁻² . It was confirmed to increase. This high electrical performance was also observed in embossed-PDMS prepared with intanglio-PDMS template (Fig. 12, Fig. 13). In particular, the size of the convex portion of the embossed-PDMS decreases from 4.6 (for 5 μm embossed-FTENG) to 0.8 μm (for 1 μm embossed-FTENG), and as the compression force increases from 10 to 90 N, the output voltage and current density are 171. V and 104 mA · m ^-2 increased significantly, which was almost the same as measured with 1 μm intaglio-FTENG. These results indicate that the triboelectric film can exhibit high electrical output when there is a significant increase in surface area under the same compressive force.

In addition, in order to improve the electrical performance by increasing the contact area of the FTENGs according to the present invention, the present invention introduced Dual embossed-PDMS (Figs. 14 and 15), specifically colloid colloidal array of PS particles of 2 ㎛ diameter After electrostatic adsorption of cationic polyethyleneimine (PEI) on a PDMS substrate having a monolayer film, a PS colloid having a diameter of about 600 nm was deposited on the PS colloidal particles forming the colloidal monolayer film, thereby preparing a dual embossed-PDMS film. The pattern of the dual embossed-PDMS film is formed by integrally fusing convex portions of different sizes on the PDMS substrate, and thus exhibits high mechanical stability under cyclic compressive force. 16 and 17, the output voltage and current density of the triboelectric element in which the Dual embossed-PDMS is introduced are approximately 207 V and 141 mA / m ² under a compression force of 90 N, according to the present invention. It exhibits higher electrical performance compared to the triboelectric element in which the embossed triboelectric film is introduced. In addition, it can be seen that the electrical performance of the triboelectric element in which the Dual embossed-PDMS is introduced is stably maintained for about 18,000 cycles under 5 Hz (FIG. 18).

Next, in order to measure the effect of Dual embossed-PDMS, analytical simulation using COMSOL multiphysics software was performed (FIG. 19). As a result, the triboelectric potential of the dual embossed-PDMS film was significantly increased as the contact area was increased, which means that higher charge density was generated on the surface than the flat-PDMS and embossed-PDMS films. Considering that the increase in triboelectric charge density is directly related to the increase in transferred charge and the high triboelectric potential difference between electrodes, the high electrical performance of Dual embossed-PDMS is closely related to the shape of the double-embossed pattern. It can be seen.

In addition, the effect of the superhydrophobic surface on the electrical performance of the triboelectric element in a humid environment was investigated. The contact angles for the water droplets of the flat-PDMS, 1 μm embossed-PDMS, 2 μm embossed-PDMS and dual embossed-PDMS films were 106, 125, 125 and 136 °, respectively (Fig. 20). The high contact angle at the surface of the dual, dual embossed-PDMS film is due to the hierarchical double relief pattern and the low surface energy of the PDMS. This hydrophobicity makes it possible to effectively sort out the formation of a water moisture layer which results in a decrease in the triboelectric charge ability, which means that it can be very useful for maintaining the electrical performance of the triboelectric element. Based on these results, the influence of relative humidity on the output voltage of flat-TENG, 1 μm embossed-FTENG, 2 μm embossed-FTENG and Dual embossed-FTENG was measured. As shown in FIG. 21, as the relative humidity increases, the output voltage of all devices is rapidly decreased due to the loss of triboelectric charge, whereas the dual embossed-FTENG according to the present invention has an output voltage at 80% relative humidity. It was measured as high as approximately 174 V. These results demonstrate that the electrical performance of Dual embossed-FTENG is less sensitive to humidity than other devices. This means that the surface of the Dual embossed-FTENG with superhydrophobic surface can effectively prevent the formation of a moisture layer that emits triboelectric charges.

In order to investigate the practicality of the dual embossed-FTENG according to the present invention, a DC circuit composed of 50 LEDs and a power supply was designed without a capacitor (FIG. 22), and the green LED was turned on using the dual embossed-FTENG according to the present invention. Through this, it was confirmed that the dual embossed-FTENG according to the present invention can provide power by using wasted mechanical energy.

According to the present invention, it is possible to provide a triboelectric device having excellent electrical performance as well as moisture resistance and high mechanical stability.

Claims (11)

1. (a) spin coating a mixture of a prepolymer of polydimethylsiloxane and a crosslinking agent onto a silicon wafer to form a plurality of polydimethylsiloxane substrates;

   (b) placing negatively charged colloidal particles on a first polydimethylsiloxane substrate of the plurality of polydimethylsiloxane substrates, and then rubbing to a second polydimethylsiloxane substrate of the plurality of polydimethylsiloxane substrates. Forming a colloidal monolayer film in which the colloidal particles are arranged on the second polydimethylsiloxane substrate; And

   (c) preparing a negative pattern triboelectric film by pouring and curing a mixture of a prepolymer of polydimethylsiloxane and a crosslinking agent on a second polydimethylsiloxane substrate on which the colloidal monolayer film is formed; Method for producing a film.
2. The method of claim 1,

   The intaglio pattern triboelectric film manufacturing method of the triboelectric film, characterized in that the intaglio pattern including a plurality of dome (dome) concave recessed recessed on one surface is formed.
3. The method of claim 1,

   The diameter of the colloidal particles is a method of producing a triboelectric film, characterized in that 0.1 to 10 ㎛.
4. The method of claim 1,

   Peeling the intaglio pattern triboelectric film of step (c) from the second polydimethylsiloxane substrate; And

   A method of manufacturing a triboelectric film, comprising: preparing a relief pattern triboelectric film by pouring and curing a mixture of a prepolymer of polydimethylsiloxane and a crosslinking agent on the exfoliated intaglio triboelectric film.
5. The method of claim 4, wherein

   The embossed pattern triboelectric film is a triboelectric film manufacturing method characterized in that the embossed pattern comprising a plurality of dome (dome) convex portion protruded convexly formed on one surface.
6. The method of claim 4, wherein

   And depositing colloidal particles having a smaller diameter than the colloidal particles on the colloidal particles between the steps (b) and (c).
7. In accordance with claim 6,

   The embossed pattern triboelectric film includes a plurality of dome-shaped first convex portions protruding from one surface and a plurality of second convex portions smaller in size than the first convex portion on the first convex portion. Method for producing a triboelectric film characterized in that the double-embossed pattern is formed.
8. The method of claim 6,

   The diameter of the deposited colloidal particles is a method of producing a triboelectric film, characterized in that 0.03 to 3 ㎛.
9. The method of claim 6,

   Trichloroperfluorooctylsilane (trichloro (1H, 1H, 2H, 2H-perfluorooctyl) silane), perfluorooctyltriethoxysilane (1H, 1H, 2H, 2H-perfluorotriethoxysilane) on the surface of the relief pattern triboelectric film , Hydrophobically modifying the surface of the relief pattern triboelectric film by treating a fluorine silane-based organic material selected from the group consisting of perfluorodecyltriethoxysilane (1H, 1H, 2H, 2H-perfluorodecyl-triethoxysilane); Method for producing a triboelectric film further comprising.
10. A triboelectric film produced according to any one of claims 1 to 9.
11. A triboelectric element comprising a triboelectric film according to claim 10.

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