TWI809731B - Triboelectric generator and method for manufacturing same - Google Patents

Abstract

A friction generator includes a friction unit and a pair of friction units. The friction unit includes a first electrode layer stacked on each other and a friction layer, the friction layer is made of polymer fiber doped with seaweed powder. The pair of friction units includes a second electrode layer stacked on top of each other, and a counter friction layer made of polymer material, the friction unit and the pair of friction units are arranged in parallel in the same direction, and the friction layer and the pair The friction layers are opposite each other. By doping the seaweed powder into the polymer fiber, it is not easy to fall off from the friction layer due to external force, and the triboelectricity of the polymer fiber is improved, and the friction layer has a higher specific surface area . In addition, the invention also provides a manufacturing method of the friction layer of the friction generator.

Description

Triboelectric generator and method for manufacturing same

The invention relates to a friction generator and a method for manufacturing the friction layer thereof, in particular to a friction generator with a fiber structure and a method for manufacturing the friction layer thereof.

Triboelectric generator (Triboelectric generator) is based on the principle of triboelectricity, to convert the mechanical energy generated by contact and friction between different materials into electrical energy, and can be applied to microelectronic components or wearable electronic components with low power consumption. Generally speaking, the friction generator includes a friction layer, and a counter-friction layer corresponding to the friction layer, and at least one of them is provided with an electrode that can be connected to the outside, so as to connect the friction layer and the counter-friction layer The current generated by triboelectrification is output to the outside. Therefore, the material selection of the friction layer and the pair of friction layers (such as the polarity difference between the two materials, the ability to lose or capture electrons) is one of the research focuses in this field.

Among them, a research team (Saqib, Q.M et al., Nano Energy 2021, 89, 106458) proposed that seagrass could be selected as the friction layer of the friction generator, which mainly dried and ground the seaweed into seaweed powder, and then configured it into seaweed The aqueous solution of powder, and forms this tribological layer on an electrode by spraying mode, because this seaweed powder itself has more oxygen-containing functional groups, can be used as good positive electrode material of triboelectricity, yet, because this frictional generation The motor generates electricity by friction and contact between the friction layer and the pair of friction layers. Therefore, as the use time increases, the seaweed powder is easy to fall off from the friction layer, and the power generation efficiency decreases, and the service life of the product is not long. question.

Therefore, the object of the present invention is to provide a friction generator, the friction layer of which is not easy to be damaged as the usage time increases.

Therefore, the friction generator of the present invention includes a friction unit and a pair of friction units.

The friction unit includes a first electrode layer stacked on each other and a friction layer, the friction layer is made of polymer fiber doped with seaweed powder.

The pair of friction units includes a second electrode layer stacked on top of each other, and a counter friction layer made of polymer material, the friction unit and the pair of friction units are arranged in parallel in the same direction, and the friction layer and the pair The friction layers are opposite each other.

In addition, another object of the present invention is to provide a method for manufacturing a friction layer of a friction generator.

Therefore, the manufacturing method of the friction layer of the triboelectric generator of the present invention includes a pretreatment step and a friction layer forming step.

In the pretreatment step, after the seaweed is dried, the seaweed powder is formed by grinding.

The step of forming the friction layer is to mix the seaweed powder into a polymer solution, and form a friction layer made of polymer fibers doped with seaweed powder on an electrode layer made of conductive material by electrospinning , and a friction unit is obtained.

The effect of the present invention is that: the seaweed powder can make the friction layer a better triboelectric positive electrode material, and by doping the seaweed powder into the polymer fiber, it is difficult for the friction layer In addition, because the friction layer has a fiber structure, it can have a higher specific surface area within the same range, so that the friction generator has better power generation efficiency.

Before the present invention is described in detail, it should be noted that in the following description, similar elements are denoted by the same numerals. And the relevant technical content, features and functions of the present invention will be clearly presented in the following detailed description of the embodiments with reference to the drawings. In addition, it should be noted that the drawings of the present invention only represent the structure and/or relative positional relationship between components, and are not related to the actual size of each component.

Referring to FIG. 1 and FIG. 2 , the friction generator of the present invention includes a friction unit 2 and a pair of friction units 3 , and the friction unit 2 and the pair of friction units 3 are arranged in parallel along the same direction X.

The friction unit 2 includes a friction layer 21 , a first electrode layer 22 , and a first bearing layer 23 stacked on top of each other. The friction layer 21 is composed of polymer fibers 211 doped with seaweed powder 212 , and the polymer fibers 211 are produced by electrospinning. The first electrode layer 22 is selected from conductive materials, and can be electrically connected to the outside through wires (not shown) or other electronic components. The first bearing layer 23 is made of insulating material, and is arranged on the side of the first electrode layer 22 opposite to the friction layer 21 to support the friction layer 21 and the first electrode layer 22, and at the same time as the friction generator. Where the force is applied.

In this embodiment, the thickness of the friction layer 21 is between 20 μm and 200 μm, and the diameter of the polymer fiber 211 constituting the friction layer 21 is between 100 nm and 500 nm, and the polyvinyl butyral (Polyvinyl butyral, PVB ) as an example. The seaweed powder 212 is obtained by drying and grinding seaweed into powder, and the surface of which is modified with dopamine, and the particle size is between 30nm and 100nm. Wherein, the seaweed is selected from Isochrysis galbana, which contains more oxygen-containing functional groups and can be used as a good triboelectric positive electrode material.

In other embodiments, the polymer fiber 211 of the triboelectric generator can be selected from other polymer materials suitable for the electrospinning process, such as: polyvinyl alcohol (PVA), polyacrylamide (PAM), hydrolyzed polypropylene Hydrolyzed polyacrylamide (HPAM), or polyvinylpyrrolidone (PVP). The seaweed may be selected from Chaetoceros muelleri, Nannochloropsis oculate, or Tetraselmis chui.

It should be noted that, in some embodiments, the polymer fiber 211 can also be doped with seaweed powder 212 whose surface is not modified, or the surface of the seaweed powder 212 is modified by other chemical components according to design requirements, As long as the friction layer 21 is composed of the polymer fiber 211 doped with the seaweed powder 212 , the aforementioned examples are not limited.

The pair of friction units 3 includes a pair of friction layers 31, a second electrode layer 32, and a second bearing layer 33 stacked on each other, and the pair of friction layers 31 and the friction layer 21 of the friction unit 2 are opposite to each other. (see picture 1). The pair of friction layers 31 is selected from polymer materials that are triboelectric negative electrode materials relative to the friction layer 21 . The second electrode layer 32 is selected from conductive materials, can be electrically connected to the outside through wires (not shown) or other electronic components, and can be the same or different from the material of the first electrode layer 22 . The second bearing layer 33 is made of insulating material, and the material of the first bearing layer 23 can be the same or different, and the second bearing layer 33 is arranged on the side of the second electrode layer 32 opposite to the pair of friction layers 31 , which can be used to support the pair of friction layers 31 and the second electrode layer 32, and serve as a force applying place for the friction generator.

In this embodiment, the thickness of the friction layer 31 is between 5 μm and 30 μm, and is selected from polyimide (PI), and relative to the polymer fiber 211 doped with seaweed powder 212 and made of PVB is Good triboelectric negative electrode material.

In other embodiments, the friction layer 31 can also be selected from polytetrafluoroethylene (PTFE), ethylene terephthalate (PET), polyvinyl chloride (PVC), polypropylene (PP), Polyethylene (PE), polystyrene (PS), polycarbonate (PC), or polymethyl methacrylate (PMMA), but not limited to the aforementioned examples, as long as it is compared with the corresponding friction layer 21, It can be used as a negative electrode material for triboelectrification.

In this embodiment, the friction generator operates in a vertical contact-separation mode (Vertical Contact-Separation). When in use, a force is applied to the first bearing layer in a vertical direction (that is, perpendicular to the direction X). 23 and at least one of the second bearing layer 33 to drive the friction layer 21 and the pair of friction layers 31 to perform a continuous action of contacting and separating from each other. In the process of actuation, based on the triboelectrification effect, part of the electrons on the surface of the friction layer 21 will be transferred to the counter friction layer 31, so that the surfaces of the friction layer 21 and the counter friction layer 31 are respectively positively charged and negatively charged, Therefore, when the friction layer 21 is separated from the pair of friction layers 31 , a potential difference will be generated between them, thereby generating an output current.

In detail, because the seaweed powder 212 contains more oxygen-containing functional groups, it can also improve the triboelectricity of the polymer fiber as a whole, so that the friction layer 21 can be more conducive to positive charging after triboelectrification. , so through the addition of the seaweed powder 212, it can help the friction layer 21 become a better triboelectric positive electrode material, and since the seaweed powder 212 is doped in the polymer fiber 211, the polymer fiber The 211 dimension can provide protection and fixation, so that the seaweed powder 212 is not easy to fall off from the friction layer 21 due to external force (friction contact), so that the power generation efficiency of the friction generator will not decrease with the increase of use time. In addition, the friction layer 21 having a fiber structure has a higher specific surface area within the same range, so that when the triboelectric generator operates, more electrons from the friction layer 21 can be transferred to the pair of friction layers 31 due to friction. , which has better power generation efficiency.

With reference to FIG. 3 , the aforementioned friction layer 21 of the triboelectric generator is manufactured through the following manufacturing method, and the manufacturing method includes a pretreatment step 41 and a friction layer forming step 42 in sequence.

The pretreatment step 41 is to dry the seaweed, form seaweed powder 212 by grinding, then immerse the seaweed powder 212 in a dopamine solution for surface modification, and then dry the seaweed powder 212 to obtain Seaweed powder 212 with dopamine-modified surface.

Specifically, in the pretreatment step 41, after the seaweed is air-dried and ground, it will first undergo a centrifugation process to filter out some impurities, and then dry it to obtain a seaweed powder 212 with a relatively uniform particle size (between 30nm and 100nm). Then use a buffer (selected from Tris-HCl) as a solvent to prepare the dopamine solution, and add the seaweed powder 212 for surface modification, followed by centrifugation, drying and other steps in order to obtain a surface modified by dopamine The seaweed powder 212 of.

The friction layer forming step 42 is to uniformly mix the seaweed powder 212 into a polymer solution, and form a doped electrode layer (ie, the first electrode layer 22 ) on an electrode layer made of a conductive material by electrospinning. There is a friction layer 21 made of high molecular fiber 211 of seaweed powder 212 to make a friction unit 2 . Wherein, the side of the electrode layer opposite to the friction layer 21 is also provided with a bearing layer made of an insulating material, that is, the first bearing layer 23).

In the friction layer forming step 42, the seaweed powder 212 is evenly mixed into the polymer solution. Since the surface of the seaweed powder 212 is modified by dopamine and has hydroxyl groups, it is difficult to agglomerate with each other. and can be evenly distributed in the polymer solution, and then, when performing the electrospinning process, the humidity of the external environment is controlled between 45% and 60%, the temperature is controlled between 20°C and 25°C, and the A voltage between 15kV to 25kV is used for electrospinning process to produce the friction layer 21, and since the seaweed powder 212 is uniformly dispersed in the polymer solution, the seaweed powder 212 can be evenly distributed in the polymer solution In the obtained polymer fiber 212.

It should be noted that the surface modification method of the seaweed powder 212 and the relevant condition parameters of the electrospinning process will vary due to experimental requirements or material selection, and are not limited to the aforementioned examples. The setting conditions of the process It has already been known by those in the relevant fields, and it is not the focus of this case, so it will not be repeated here.

To sum up, the addition of the seaweed powder 212 to the triboelectric generator of the present invention can help the friction layer 21 become a better triboelectric positive electrode material, and because the seaweed powder 212 is doped in the polymer fiber 211 It is not easy to fall off from the friction layer 21 due to external force, so the power generation efficiency of the friction generator will not decrease with the increase of use time, and the friction layer 21 with fiber structure has a higher specific surface area, so that the The friction generator has better power generation efficiency, so it can really achieve the purpose of the present invention.

But the above-mentioned ones are only embodiments of the present invention, and should not limit the scope of the present invention. All simple equivalent changes and modifications made according to the patent scope of the present invention and the content of the patent specification are still within the scope of the present invention. Within the scope covered by the patent of the present invention.

2: Friction unit

21: friction layer

211: polymer fiber

212: seaweed powder

22: The first electrode layer

23: The first bearing layer

3: Counter friction unit

31: Counter friction layer

32: Second electrode layer

33: Second bearing layer

41: Preprocessing steps

42: Friction layer formation step

X: direction

Other features and effects of the present invention will be clearly presented in the implementation manner with reference to the drawings, wherein: Fig. 1 is a schematic side view illustrating an embodiment of the friction generator of the present invention; Fig. 2 is a partial schematic diagram, Auxiliary Explanation The enlarged view of A in FIG. 1 illustrates the composition structure of the friction layer of the friction generator; and FIG. 3 is a flow chart illustrating the manufacturing method of the friction layer of the friction generator.

2: Friction unit

21: friction layer

22: The first electrode layer

23: The first bearing layer

3: Counter friction unit

31: Counter friction layer

32: Second electrode layer

33: Second bearing layer

X: direction

Claims (8)

A friction generator, comprising: a friction unit, including a first electrode layer stacked on each other, and a friction layer, the friction layer is composed of polymer fibers doped with seaweed powder, and the seaweed powder The surface is modified by dopamine; and a pair of friction units, including a second electrode layer stacked on each other, and a counter friction layer made of polymer material, the friction unit and the pair of friction units are arranged in parallel in the same direction, and The friction layer and the pair of friction layers are made to face each other. The triboelectric generator according to claim 1, wherein the thickness of the friction layer is between 20 μm and 200 μm, the diameter of the polymer fibers constituting the friction layer is between 100 nm and 500 nm, and the particle size of the seaweed powder is between 30 nm to 100nm. The friction generator according to claim 1, wherein the friction unit further includes a first bearing layer arranged on the side of the first electrode layer opposite to the friction layer, and the pair of friction units further includes a first bearing layer arranged on the first electrode layer The second electrode layer is opposite to the second bearing layer on the side of the pair of friction layers, and can apply force to at least one of the first bearing layer and the second bearing layer to drive the friction layer and the pair of friction layers to contact each other. . A method for manufacturing a friction layer of a triboelectric generator, which is used to manufacture the friction unit as described in claim 1, comprising: a pretreatment step of drying the seaweed and then grinding it to form seaweed powder; and a friction layer Forming step, mixing the seaweed powder into a polymer solution In the process, a friction layer made of polymer fiber doped with seaweed powder is formed on an electrode layer made of conductive material by electrospinning, and a friction unit is produced. The method for making the friction layer of a triboelectric generator as described in claim 4, wherein the pretreatment step is to first dry and grind a seaweed into the seaweed powder, and then immerse the seaweed powder in a dopamine solution for surface treatment. modified, and after drying, the surface of the seaweed powder modified by dopamine is obtained. The manufacturing method of the friction layer of the friction generator as described in Claim 4, wherein, in the step of forming the friction layer, the humidity of the external environment is controlled between 45% and 60%, and the temperature is controlled between 20°C to 25° C. and apply a voltage between 15 kV and 25 kV to carry out the electrospinning process. The manufacturing method of the friction layer of the friction generator as claimed in item 4, wherein, the electrode layer is arranged on a bearing layer made of insulating material, and the friction layer is formed on the electrode layer opposite to the bearing layer side of the layer. The manufacturing method of the friction layer of the friction generator as claimed in claim 4, wherein the thickness of the friction layer is between 20 μm and 200 μm, the diameter of the polymer fiber is between 100 nm and 500 nm, and the particle size of the seaweed powder is between From 30nm to 100nm.

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