KR20210026720A - Triboelectric nanogenerator utilizing triboelectrification and ion-enhanced field emission - Google Patents

Abstract

The present invention relates to an electrostatic device which enables energy harvesting by triboelectrification and field emission. According to the present invention, the electrostatic device which enables energy harvesting by the triboelectrification and field emission includes: a pair of electrodes spaced apart from each other to form a potential difference; an electrified body disposed between the pair of electrodes, made of a material capable of triboelectrification, and causing triboelectrification with any one of the pair of electrodes; a conductor disposed under the electrified body at a position not in contact with the other one of the pair of electrodes, and including a field emission part exposed to the outside of the electrified body to enable field emission by contact and separation with any one electrode; and an insulating layer disposed between the other electrode and the conductor.

Description

Electrostatic device enabling energy harvesting by triboelectric charging and field emission {Triboelectric nanogenerator utilizing triboelectrification and ion-enhanced field emission}

The present invention relates to an electrostatic device that enables energy harvesting by triboelectric charging and electric field emission, and more particularly, to enable energy harvesting by electric field emission as well as triboelectric charging, so that energy harvesting efficiency can be increased. It relates to an electrostatic device that enables energy harvesting by improved triboelectric charging and field emission.

Triboelectric nanogenerators allow energy to be harvested by triboelectric charging. Compared to electromagnetic induction generators, triboelectric nanogenerators have advantages such as small size and light weight, making them suitable for portable electronic devices, and energy harvesting. It is a device that is attracting worldwide attention in the field.

In general, electrostatic devices have a structure in which a dielectric having a surface charge exists between two electrodes, and limitations that are difficult to be applied to practical use, such as limiting output due to air breakdown, have been suggested.

Efforts to increase the electrical output by changing the dielectric material to increase the surface charge or by increasing the surface area of the material through micro/nano structures in order to increase the electrical output of the electrostatic device are continuing, but the breakdown of air when the surface charge is high There is a disadvantage in that the output is limited by.

In addition, additional components and circuits not only increase the volume, but also require a special packaging solution to prevent damage and malfunction of existing circuits due to high surface charge, and increase the manufacturing cost of devices, making them a representative application industry for energy harvesting. There is a drawback that is difficult to apply to portable devices/independent sensors.

Therefore, there is a demand for developing electrostatic devices that can increase energy harvesting efficiency without significantly changing the existing structure without expanding the component standard or by a special packaging solution.

Republic of Korea Patent Publication Registration No. 10-1398708 Japanese Published Patent Publication No. 2017-518512

The present invention has been conceived to solve the above problems, and an object of the present invention is to provide an electrostatic device capable of harvesting energy by electric field emission as well as frictional charging by a simple configuration.

An electrostatic element capable of harvesting energy by frictional charging and electric field emission according to the present invention for achieving the above object comprises: a pair of electrodes disposed at positions spaced apart from each other to form a potential difference; A charger disposed between the pair of electrodes, made of a material capable of frictional charging, and causing a frictional charge with any one of the pair of electrodes; An electric field exposed to the outside of the charger so that the electric field is disposed below the charger and is not in contact with the other of the pair of electrodes, and discharges the electric field by contacting and separating the electrode A conductor comprising a discharge portion; And an insulating layer disposed between the other electrode and the conductor.

It is preferable that the electric charge body includes an exposed hole that enables external exposure of the field emission portion of the conductor.

It is preferable that the charger includes a first charging portion in which the exposed hole is formed, and a second charging portion corresponding to the insulating layer and integrally formed with the first charging portion.

In the present invention, the charging surface of the charger causing frictional charging with any one electrode is a plurality of exposed holes formed so that a plurality of elements located on the same plane can be in contact with the one electrode at the same time. It may be formed by including the raised portions and stepped grooves formed between the raised portions.

In the electrostatic element that enables energy harvesting according to the present invention having the configuration as described above, a conductor is disposed separately from a charging body, but a part of the conductor passes through the charging body and is exposed to the air and is in direct contact with the electrode. Thus, energy harvesting by electric field emission as well as triboelectric charging is possible without significantly changing the basic configuration causing triboelectric charging, and thus energy harvesting efficiency can be improved even with a simple configuration.

1 is a partially cut-away perspective view for explaining the structure of an electrostatic element capable of harvesting energy by frictional charging and electric field emission according to an embodiment of the present invention.
Figure 2 is a cross-sectional view showing a separate configuration of an embodiment of the present invention.
3 is a view for explaining an electrical output form by a field emission phenomenon employed in an embodiment of the present invention.
4 is a view for explaining the principle of field emission according to an embodiment of the present invention.
5 is a view for explaining the voltage and current output results according to an embodiment of the present invention.
6 is a view for comparing the effective output compared to the conventional electrostatic device according to an embodiment of the present invention.
7 is a partially cut-away perspective view of an electrostatic element enabling energy harvesting by triboelectric charging and electric field emission according to another embodiment of the present invention.

In the following description, in order to clarify an understanding of the present invention, a description of known techniques for features of the present invention will be omitted. The following embodiments are detailed descriptions to aid understanding of the present invention, and it will be natural that the scope of the present invention is not limited. Accordingly, an equivalent invention that performs the same function as the present invention will also fall within the scope of the present invention.

In addition, in the following description, the same identification symbols mean the same configuration, and unnecessary redundant descriptions and descriptions of known technologies will be omitted. In addition, the description of each of the embodiments of the present invention, which overlaps with the description of the technology behind the background of the present invention, will also be omitted.

Hereinafter, an electrostatic element capable of harvesting energy by frictional charging and electric field emission according to an embodiment of the present invention will be described in detail with reference to the accompanying drawings.

1 is a partially cut-away perspective view for explaining the structure of an electrostatic element capable of harvesting energy by frictional charging and electric field emission according to an embodiment of the present invention, and FIG. 2 is a separate perspective view of an embodiment of the present invention. Fig. 3 is a cross-sectional view shown, and Fig. 3 is a view for explaining the principle of field emission according to an embodiment of the present invention, and Fig. 4 is a view for explaining an electrical output form by field emission phenomenon employed in an embodiment of the present invention, and Fig. 5 Is a view for explaining the voltage and current output results of an embodiment of the present invention, Figure 6 is a view for comparing the effective output compared to the conventional electrostatic element of the embodiment of the present invention.

1 and 2, an electrostatic element (hereinafter referred to as'electrostatic element') that enables energy harvesting by frictional charge and field emission according to an embodiment of the present invention, causes frictional charge. By utilizing the structure, it is possible to improve the energy harvesting efficiency by electric field emission as well as triboelectric charging. A pair of electrodes 11 and 12, a charger 2, a conductor 3, and an insulating layer 4 ).

The pair of electrodes 11 and 12 are disposed at positions spaced apart from each other to form a potential difference, thereby enabling the movement of electrons by triboelectric charging and field emission, thereby harvesting energy.

The first charging portion 21 of the charger 2 is disposed between the pair of electrodes 11 and 12, and is not only a material that is easily charged with (-) (PTFE, Polyimide, etc.), It is made of a material capable of frictional charging, such as a material that is easily charged with (+) (Nylon, Polypropylene, etc.), and is repeatedly contacted and separated with any one of the pair of electrodes 11 and 12. It causes frictional warfare.

It goes without saying that the friction means for contacting and separating the charger 2 and any one electrode 11 from each other may be implemented in various ways depending on the product to which the present embodiment is applied. That is, as the friction means, when the present embodiment is applied to a product that is disposed on a moving path of a pedestrian or a vehicle to generate repetitive vertical vibration by the moving object, the electrode 11 and the charger ( 2) An elastic body such as a spring (not shown) may be employed between the two, and in the case of a product in which frictional charge occurs due to a sliding operation between the electrode 11 and the charger 2, a motor ( Of course, a driving means such as (not shown) may be employed.

This embodiment includes a conductor 3 that is not employed in a conventional triboelectric element so that energy can be harvested by field emission, apart from energy harvesting by such frictional charging.

That is, the conductor 3 is disposed below the charger 2, at a position not in contact with the other one 12 of the pair of electrodes 11 and 12, and the charger 2 ) By including the field emission part 31 exposed to the outside, it enables electric field emission by contacting and separating any one of the electrodes 11 above.

This field emission part 31 allows electrons to move directly to the electrode 11 in addition to moving by frictional charging between the first charging part 21 and the electrode 11 of the charging body 2. , Makes it possible to increase the output of the electrostatic element.

In other words, conventional electrostatic devices are completely blocked by a charged material between the electrode and the electrode, so if the surface charge of the charged material is too large, the size of the output is limited by the breakdown phenomenon of air, and micro-sized foreign matter enters between the electrode and the charged material. It may interfere with the generation of output.

However, in the present embodiment, the field emission part 31 is exposed to the air and the electrons can be directly contacted with the one electrode 11 so that the electrons can be moved directly to the one electrode 11. As a result, it is possible to increase the output through the direct movement of electrons.

The field emission part 31 employed in this embodiment is based on the principle of ion-enhanced field emission, and has an output type as shown in FIG. 3. That is, the ion-enhanced field emission is instantaneously generated when a high voltage and current output is in contact between the field emission part 31 and the electrode 11 of the metal unlike the conventional electrostatic element.

The ion-enhanced field emission phenomenon refers to a phenomenon in which electrons can be emitted to the outside even if the strength of the electric field is weak because the work function of the metal is lowered due to ions outside the metal. That is, as well shown in FIG. 4, electrons protruding from the field emission part 31 move at a high speed by the electric field, and move to the upper electrode 11 while ionizing other molecules in the air.

In the electrostatic device according to the present embodiment to which the principle of ion-enhanced field emission is applied, unlike the conventional electrostatic device, unlike the conventional electrostatic device, not only the voltage but also the current is measured very high through a mechanism in which electrons move directly. .

In addition, the effective output of the electrostatic element according to the present embodiment is a measurement value of an AC voltage having the same energy as the DC voltage, and as well as shown in FIG. 6, when the same input energy is given, the effective output is about 6.3 compared to the conventional electrostatic element. The ship was largely generated.

As described above, in the electrostatic element that enables energy harvesting by frictional charging and electric field emission according to an embodiment of the present invention, the conductor 3 is arranged separately from the charging body 2, but a part of the conductor 3 is By passing through the charger 2, exposing it to the air and making it in direct contact with the electrode 11, it is possible to harvest energy by electric field emission as well as frictional charge without significantly changing the basic configuration that causes frictional charge. Even one configuration has the effect of improving energy harvesting efficiency.

On the other hand, the insulating layer 22 (also referred to as a second charging portion in this embodiment) is disposed between the other electrode 12 and the conductor 3 to connect the electrode 12 and the conductor 3 It serves to insulate each other.

The charger 2 includes an exposed hole 21a that allows the field emission part 31 of the conductor 3 to be exposed to the outside, so that the field emission part 31 is attached to the electrode 11. Make direct contact.

The charger 2 may be formed separately from the insulating layer 22 described above, but in the present embodiment, a configuration in which a part of the charger 2 can exhibit an insulating function is adopted.

That is, the charger 2 includes a first charging portion 21 having an exposed hole 21a for exposing the field emission hole, and the first charging portion 21 corresponding to the insulating layer. It comprises a second charging portion 22 formed integrally with.

This embodiment having such a configuration makes it possible to manufacture the charger 2 in a double injection method in which the charger 2 is injected together with the conductor 3 while the conductor 3 is inserted into the mold. It makes it possible to expect advantages that can improve the molding efficiency and structural stability of the product.

Hereinafter, an electrostatic element that enables energy harvesting by frictional charging and field emission according to another embodiment of the present invention will be described in detail with reference to FIG. 7.

7 is a partially cut-away perspective view of an electrostatic element enabling energy harvesting by triboelectric charging and electric field emission according to another embodiment of the present invention.

In the embodiment shown in this figure, a structure is adopted so that movement of electrons due to frictional charging and electric field emission can occur at multiple points (or regions) even by a single friction.

That is, the charging surface of the charger 100 employed in the present embodiment is a plurality of raised portions 101 in which exposed holes are formed so that a plurality of elements located on the same plane can be in contact with any one of the electrodes at the same time. And the stepped grooves 102 formed between the ridges and the raised portions 101.

In the present embodiment having such a configuration, as electron movement occurs simultaneously in the plurality of raised portions 101 by one frictional operation between any one electrode and the charger 100, energy harvesting efficiency can be further improved. Has an advantage.

Various embodiments of the present invention have been described above, but the present embodiment and the accompanying drawings are merely illustrative of some of the technical ideas included in the present invention, and are included in the specification and drawings of the present invention. It will be apparent that all modified examples and specific embodiments that can be easily inferred by a person skilled in the art within the scope of the technical idea are included in the scope of the present invention.

11, 12: electrode 2: whole
21: All 1st War 21a: Exposed
22: All the second generation (insulation layer) 3: Conductor
31: field emission unit

Claims (4)

A pair of electrodes disposed at positions spaced apart from each other to form a potential difference;
A charger disposed between the pair of electrodes, made of a material capable of frictional charging, and causing a frictional charge with any one of the pair of electrodes;
An electric field exposed to the outside of the charger so that the electric field is disposed below the charger and is not in contact with the other of the pair of electrodes, and discharges an electric field by contacting and separating the electrode A conductor comprising a discharge portion; And
An electrostatic device capable of harvesting energy by triboelectric charging and electric field emission, comprising: an insulating layer disposed between the other electrode and the conductor. The method of claim 1,
The electrostatic element enabling energy harvesting by frictional charging and electric field emission, wherein the electric charge body comprises an exposed hole for allowing external exposure of the electric field emission part of the conductor. The method of claim 2,
The charging unit includes a first charging unit in which the exposed hole is formed, and a second charging unit corresponding to the insulating layer and integrally formed with the first charging unit. An electrostatic element that enables energy harvesting. The method of claim 2,
The charging surface of the charger causing frictional charging with any one electrode is provided with a plurality of protrusions in which the exposed hole is formed so that a plurality of elements located on the same plane can contact the one electrode at the same time. An electrostatic element that enables energy harvesting by frictional charging and electric field emission, comprising: stepped grooves formed between the raised portions.

Images