CN111200376A

CN111200376A - A triboelectric nanogenerator

Info

Publication number: CN111200376A
Application number: CN201811507401.0A
Authority: CN
Inventors: 温荣梅; 翟俊宜
Original assignee: Beijing Institute of Nanoenergy and Nanosystems
Current assignee: Beijing Institute of Nanoenergy and Nanosystems
Priority date: 2018-11-19
Filing date: 2018-12-10
Publication date: 2020-05-26
Anticipated expiration: 2038-12-10
Also published as: CN111200376B

Abstract

The invention provides a friction nano generator. The friction layer of the friction nano generator is composed of a nano composite film, wherein the nano composite film is formed by compounding a high molecular polymer and a metal organic framework. The nano composite film is used as a friction layer of the friction nano generator, the output performance of the friction nano generator is improved along with the increase of the humidity, the nano composite film is particularly suitable for being applied in a high-humidity environment, and the actual application range of the nano composite film is greatly widened.

Description

Friction nanometer generator

Technical Field

The invention relates to the field of generators, in particular to a friction nano generator.

Background

Due to environmental problems such as global energy crisis and global warming, there is a great deal of attention paid to sustainable and environmentally friendly collection of energy from nature. Among energy collection technologies, triboelectric Nanogenerators (TENG) have proven to be an economical, effective and simple technology that can directly convert mechanical energy such as wind current, sea wave, and human motion into electrical energy. However, due to the low output performance of TENG, its large-scale commercial application is greatly limited.

Recently, various methods for solving this problem have been reported in succession, such as rational selection of friction material, injection of charge, regulation of morphology, optimization of structure, and the like, and among these methods, increasing the charge density of the surface by rational selection of friction material is the most effective method for improving the output performance of TENG. Current friction materials are generally limited to some conventional materials of the triboelectric series, but these materials are in turn subject to environmental factors (composition of the gas, humidity), which affect the performance of TENG, in particular the humidity has a great influence on the performance of TENG, increasing humidity, forming a layer of water on the friction material surface, causing charge transfer or dissipation, eventually leading to a reduction in the output performance of TENG. Therefore, from a materials perspective, it remains a challenging task to design new friction materials such that TENG has excellent output performance in different environments.

Disclosure of Invention

Technical problem to be solved

Aiming at the technical problems, the invention provides a friction nano generator which is used for at least partially solving the technical problems.

(II) technical scheme

The invention provides a friction nano generator, wherein a friction layer of the friction nano generator is formed by a nano composite film.

Optionally, the nano composite film is formed by compounding a high molecular polymer and a metal organic framework.

Optionally, the high molecular polymer is at least one of polyvinylidene fluoride, polydimethylsiloxane, polytetrafluoroethylene or polyvinyl chloride, and the metal organic framework is at least one of UiO-66, HKUST-1, ZIF-8 or MIL-101.

Optionally, the UiO-66 is prepared by using zirconium chloride as a metal salt and terephthalic acid as an organic ligand, the HKUST-1 is prepared by using copper nitrate as a metal salt and trimesic acid as an organic ligand, the ZIF-8 is prepared by using zinc nitrate as a metal salt and 2-methylimidazole as an organic ligand, and the MIL-101 is prepared by using chromium nitrate as a metal salt and terephthalic acid as an organic ligand.

Optionally, the nano composite film is compounded by polydimethylsiloxane 8 and HKUST-19.

Optionally, the mass of the HKUST-19 accounts for 1 wt% to 10 wt% of the mass of the nano composite film.

Alternatively, the triboelectric nanogenerator is of a vertical contact-separation type, a sliding type, a single electrode type, and an independent friction layer type.

Optionally, the triboelectric nanogenerator is of a vertical contact-split type comprising: an upper electrode 2; a positive friction layer 3 formed on the surface of the upper electrode 2; a lower electrode 5; the negative friction layer 4 is formed on the surface of the lower electrode 5, and the negative friction layer 4 is composed of a nano composite film; the upper electrode 2 is connected with the lower electrode 5 through an external circuit 7, and the positive friction layer 3 and the negative friction layer 4 are opposite and can be contacted and separated with each other.

Optionally, the triboelectric nanogenerator further comprises: an upper substrate 1; an upper electrode 2 is formed on the surface of the upper substrate 1; and/or, further comprising a lower substrate 6, wherein the lower electrode 5 is formed on the surface of the lower substrate 6.

Optionally, the friction layer of the nanocomposite film has a thickness in a range of 100 micrometers to 500 micrometers.

(III) advantageous effects

The invention provides a friction nano generator, wherein a friction layer is made of a nano composite film. The nano composite film is formed by compounding a high molecular polymer and a metal organic framework, and is used as a friction layer of the friction nano generator, so that the friction nano generator is free from the limit of humidity in the external environment, the output performance of the friction nano generator is improved along with the increase of the humidity, the nano composite film is particularly suitable for being applied in a high-humidity environment, and the actual application range of the friction nano generator is greatly widened.

Drawings

Fig. 1 schematically shows a structural view of a triboelectric nanogenerator according to an embodiment of the invention.

FIG. 2 is a schematic structural diagram of a PDMS + HKUST-1 based triboelectric nanogenerator according to an embodiment of the invention.

FIGS. 3a-c schematically show the short-circuit current (I) of an embodiment of the invention, respectively_SC) Open circuit voltage (V)_OC) And a schematic of the transfer charge (Q) as a function of time.

FIG. 4 is a graph schematically showing the decay time of the example of the present invention as a function of HKUST-1 content.

FIG. 5 schematically shows a surface topography of nanocomposite films for different HKUST-1 contents of an embodiment of the invention.

FIG. 6 is a graph schematically showing the dielectric constant of an embodiment of the present invention as a function of HKUST-1 content.

FIG. 7 schematically shows a graph of TENG output signal based on PDMS/HKUST-1 nanocomposite films under various relative humidity conditions according to an embodiment of the present invention.

FIG. 8 schematically shows a graph of the charge decay time of TENG with relative humidity based on PDMS/HKUST-1 nanocomposite films according to an embodiment of the present invention.

FIG. 9 schematically shows a graph of dielectric constant as a function of relative humidity for a PDMS/HKUST-1 nanocomposite film according to an embodiment of the present invention.

[ reference numerals ]

1-upper substrate

2-upper electrode

3-positive friction layer

4-negative friction layer

5-bottom electrode

6-lower substrate

7-external circuit

8-Polydimethylsiloxane (PDMS)

9-HKUST-1

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is described in further detail below with reference to specific embodiments and the accompanying drawings.

TENG is a nano generator based on triboelectrification and electrostatic induction coupling, and the basic principle is as follows: when external force is applied, the two friction materials rub against each other, charge transfer occurs, and friction charge is generated; after the deformation force is released, the two surfaces are automatically separated, and charges on the two surfaces cannot be completely neutralized due to the air layer sandwiched between the two surfaces, so that a potential difference is formed; to balance this potential difference, charges of opposite polarity are induced on the electrode plates, and an external circuit can form an instantaneous current; when external force is applied again, the electric potential generated by the friction charges is continuously reduced, the induction charges flow in the opposite direction through the external circuit until the two friction materials are contacted again, and the current returns to zero; the mechanical deformation is applied periodically in such a way that an alternating current signal is continuously generated.

TENG includes 4 modes of operation: vertical contact-separation, sliding, single electrode, and independent friction layer. The vertical contact-separation type is the earliest proposed working mode of a friction nanometer generator, the mode generates electricity by continuously contacting and separating two friction layers in the vertical direction, when the two friction layers with different triboelectric sequences are in mechanical contact, opposite charges can be generated on the surface of a material, the friction layer which is easy to lose electrons is positively charged, the friction layer which is easy to obtain electrons is negatively charged, when the two friction layers are separated, a potential difference can be generated between the corresponding electrodes, an external circuit connected between the two electrodes is connected into a resistor, free electrons can flow from one electrode to the other electrode to balance an electrostatic field, when the distance between the two electrodes is gradually reduced, the potential generated by the triboelectric charges disappears, induced electrons can flow in the opposite direction, and the periodic contact and separation between the two friction layers can cause alternating current to be generated between the two electrodes, in this mode, the power generation process relies on contact and separation between the two contact surfaces, and the output current is an alternating current.

The sliding type is based on the coupling of sliding friction electrification and a plane charge separation process under the driving of an external force parallel to the horizontal direction of the friction layer. Under the action of external force, the friction force between the contact surfaces of the two friction layers makes the two friction layers slide relatively to generate dense friction charges. The periodic change of the contact area between the surfaces of the two friction layers causes the transverse separation of the charge centers, thereby generating a potential difference and generating current in an external circuit. The single electrode type has the same triboelectric process as the former, only one electrode is contained in the single electrode type, and the current transfer is realized by utilizing the potential difference between the electrode and the grounding terminal. The independent friction layer type is composed of an independent friction layer and two friction electrodes, and power is generated through the reciprocating motion of the independent friction layer between the two friction electrodes.

At present, the most effective method for improving the output performance of TENG is to reasonably select a friction material of a friction layer for friction electrification, the traditional friction material generally adopts a single polymer matrix, and nanoparticles are embedded in the polymer matrix, so that the electrification performance of the surface of the material can be changed, the dielectric performance of the material can be changed, and the electrostatic induction process of a friction nano generator is influenced. Metal Organic Frameworks (MOFs) are crystalline materials that link inorganic metal ions (node components) to multiple organic ligands (structural linkers) via coordination chemistry, have the ability to capture electrons, and can be used as nanoparticles embedded in polymeric matrices.

Based on the above thought, the embodiment of the invention provides a preparation method of a nano composite film, wherein the composite film is formed by compounding a high molecular polymer and MOFs according to a certain proportion. The specific method comprises the following steps:

s1, mixing the high molecular polymer monomer and the curing agent uniformly according to a certain proportion (mass ratio is 10: 1), adding MOFs, and fully stirring to uniformly mix.

S2, the uniformly mixed mixture is put into vacuum drying to remove air bubbles.

S3, pouring the mixture on a rotating plane (quartz glass) to spin (spin at 500rpm for 50S), moving the quartz glass into an oven (120 ℃) to heat (the heating time is determined according to specific conditions, and in the embodiment, the heating time is 15min), so as to obtain a completely cured nano composite film, and peeling the film from the rotating plane.

Wherein the high molecular polymer is at least one of polyvinylidene fluoride (PVDF), Polydimethylsiloxane (PDMS), Polytetrafluoroethylene (PTFE) or polyvinyl chloride (PVC), and the metal organic framework is at least one of UiO-66, HKUST-1, ZIF-8 or MIL-101. MOFs is a porous inorganic-organic hybrid material formed by mutually connecting metal salt and organic ligand through coordination bonds, UiO-66 is prepared by taking zirconium chloride as metal salt and terephthalic acid as organic ligand, HKUST-1 is prepared by taking copper nitrate as metal salt and trimesic acid as organic ligand, ZIF-8 is prepared by taking zinc nitrate as metal salt and 2-methylimidazole as organic ligand, and MIL-101 is prepared by taking chromium nitrate as metal salt and terephthalic acid as organic ligand.

The embodiment of the invention provides a friction nano generator, the structure of which is shown in figure 1, and the friction nano generator comprises: an upper substrate 1 and a lower substrate 6, both of which are composed of acrylic sheets; an upper electrode 2 formed on the surface of the upper substrate 1, the upper electrode 2 being made of gold, copper or silver; a positive friction layer 3 formed on the surface of the upper electrode 2; a lower electrode 5 formed on the surface of the lower substrate 6, wherein the material of the lower electrode 5 is gold, copper or silver; the negative friction layer 4 is formed on the surface of the lower electrode 5, is composed of the nano composite film and is used for rubbing the positive friction layer 3 to generate electric charges, so that the output performance of the friction nano generator is improved along with the increase of humidity; the upper electrode 2 and the lower electrode 5 are connected by an external circuit 7, and the positive friction layer 3 and the negative friction layer 4 are located opposite to each other.

The thickness of the tribolayer of the nanocomposite film can range from 100 microns to 500 microns.

The material of the positive friction layer 3 may be polyamide (nylon) -11, polyamide (nylon) -66, melamine, or the same material as the upper electrode 2, and is determined according to the friction category of the friction nano-power generation, which is not limited in the present invention. The tribological category includes 2 categories of dielectric-dielectric materials and conductive-dielectric materials, for which TENG the conductive layer acts as both the tribological layer and the electrode.

The composite structure of the nano composite film comprises a substrate, a polymer, a metal oxide, a metal halide, a metal oxide.

Wherein, in the nano composite film, the mass of the MOFs accounts for 1 wt% -20 wt% of the mass of the nano composite film (the total mass of the high molecular polymer and the MOFs), the mass of the MOFs is distributed in a circle with the diameter of 10-1000nm, and the thickness of the nano composite film is about 100-500 μm.

The area of the nano composite film is 1cm multiplied by 2cm or 2cm multiplied by 2cm or 2.5cm multiplied by 2.5cm or 3cm multiplied by 3cm, the selection of the specific area is determined according to the actual requirement, the invention is not limited, the area is too large or too small, and the actual operation is difficult.

When the nano composite film is formed by compounding polydimethylsiloxane 8 and HKUST-19, the structure of the friction nano generator is shown in figure 2, at this time, the copper foil simultaneously plays the role of the upper electrode 2 and the positive friction layer 3, the upper electrode 2 and the positive friction layer 3 are combined into a layer, preferably, when the mass of the HKUST-19 in the nano composite film accounts for 4.5 wt% -5.5 wt% of the total mass of the nano composite film, the output performance of the friction nano generator is excellent, most preferably, the mass of the HKUST-19 accounts for 5 wt% of the total mass of the nano composite film, and the output performance of the friction nano generator is optimal. HKUST-19 is octahedral structure, and its size is distributed in the circle whose diameter is 50-500 nm.

The TENG taking the nano composite film compounded by the high molecular polymer and the MOFs as the negative friction layer has the advantages that the output performance is obviously improved, particularly the limitation of humidity is realized, the output performance of the TENG is improved along with the increase of the humidity unlike the traditional TENG, and the practical application range of the TENG is greatly widened.

In order to more clearly illustrate the invention, the embodiment of the invention tests the influence of different contents of HKUST-19 on TENG output performance when the polydimethylsiloxane 8/HKUST-19 nano composite film is used as a negative friction layer, analyzes specific reasons, and selects nano composite films with the contents of HKUST-19 of 0 wt%, 1 wt%, 3 wt%, 5 wt%, 7 wt% and 9 wt% as test objects.

FIGS. 3a-c show the short-circuit current (I), respectively_SC) Open circuit voltage (V)_OC) And the change in the transferred charge (Q) with time, as is apparent from the graph, the content of HKUST-19, I, was varied_SC，V_OCAnd Q has a similar trend with time, the intensity of the output signal generated peaks (37. mu.A, 205V and 48nC) when the HKUST-1 content was increased to 5 wt%, which are 4.6, 3.4 and 3.69 times the TENG output signal (8. mu.A, 60V and 13nC) based on pure polydimethylsiloxane 8, respectively. As the HKUST-19 content further increased from 5 wt% to 9 wt%, the intensity of the output signal generated began to decay, with the output signal increasing and then decreasing as the HKUST-19 content increased. The amount of transferred charge is an important parameter in measuring TENG output performance, which is related to the amount of charge rubbed and the dielectric constant of the negative friction layer material. The reasons for the occurrence of such variations are explained in detail below

First, the influence of triboelectric charges on the transferred charges is considered. Triboelectrification can be further divided into three sub-processes: generation of triboelectric charge, storage of triboelectric charge and electrostatic induction. In fact, electrons captured by the negative friction layer from the positive friction layer cannot stay on the surface of the negative friction layer, when the electrons accumulate on the contact surface of the two friction layers, a built-in electric field is established between the contact surface and the bottom electrode due to the accumulation of positive charges on the bottom electrode, and the direction of the electric field is vertically upward, so that two electron transfer modes, i.e., a drift process caused by the electric field and a diffusion process caused by the concentration gradient of the electrons, are generated. Both transitions may result in loss of triboelectrons due to recombination with the positive charge induced on the electrode. In addition, the loss of surface triboelectrons may also recombine with the adsorption of positively charged ions or particles in the air. The reduced triboelectric charge density eventually leads to a deterioration of the TENG output performance. When the material HKUST-19 for capturing electrons is introduced into the polydimethylsiloxane 8, the surface triboelectric electrons can be effectively captured inside the negative friction layer, and the recombination between the electrons and the positive charge in the air is inhibited due to the high electron capture property, so that the higher triboelectric charge density of TENG is realized, and the transferred charge quantity is increased.

To verify the trapped electron characteristics of HKUST-19, the charge decay times of TENG for different levels of HKUST-19 were tested at a relative humidity RH of 10% accordingly, as shown in FIG. 4. Decay time is used to characterize the electron storage capacity of different materials, indicating the time required for 1/e charge retention. The decay time of TENG was gradually increased from 130 minutes (neat polydimethylsiloxane 8) to 500 minutes as the HKUST-19 level increased to 5 wt%. This phenomenon indicates that more triboelectric charges are trapped in deeper regions of the dielectric layer. However, as the HKUST-19 content was further increased from 5 wt% to 9 wt%, the required decay time was reduced to 310 minutes, which may be attributed to the reduction in the surface area (S) of the polydimethylsiloxane 8 and the increase in the HKUST-19 content. To verify this hypothesis, the nanocomposite film surface morphology with different amounts of HKUST-19 was tested, as shown in fig. 5, and it is evident that the effective rubbing area of the negative rubbing layer decreased with increasing amounts of HKUST-19, since as the HKUST-19 content increased, an excess of HKUST-19 appeared on the surface, the reduction in the area of polydimethylsiloxane 8 on the top surface of the negative rubbing layer resulted in little triboelectric charge, and the increase in the area of HKUST-19 on the bottom surface of the negative rubbing layer resulted in loss of triboelectric electrons (recombination of positive charge and trapped charge induced on the electrodes), suggesting that this hypothesis is correct.

Second, the effect of the dielectric constant of the negative friction layer material on the transferred charge is considered. To analyze the effect of dielectric constant on transferred charge (TENG output performance), the frequency range was 10% at a relative humidity RH of 10%²～10⁶In Hz, the dielectric constant was tested as a function of HKUST-19 content, as shown in FIG. 6. It can be seen from the figure that the dielectric constant monotonically increases with the nanocomposite. From the previously reported formula, the higher the dielectric constant, the greater the transferred charge density.

Therefore, when the content of HKUST-19 was increased from 0 wt% to 5 wt% under the combined effect of the triboelectric charge density and the dielectric constant, the output performance of TENG gradually increased, and the output performance of TENG began by continuing to increase the content of HKUST-19. Preferably, in the nano composite film, the output performance of the friction nano generator is excellent when the mass of HKUST-19 accounts for 4.5 wt% -5.5 wt% of the total mass of the nano composite film, most preferably, the output performance of the friction nano generator is optimal when the mass of HKUST-19 accounts for 5 wt% of the total mass of the nano composite film, and the optimal mass ratio (5 wt%) is the competitive balance of the influences on the TENG output characteristic.

TENG is based on the coupling of the triboelectric effect and the electrostatic induction, and the performance of TENG is closely related to the environment such as humidity and a surface adsorption layer. Previous studies have demonstrated that TENG output performance generally decreases significantly with increasing Relative Humidity (RH) in the atmosphere due to the formation of a water surface skin on triboelectric surfaces. Here we also investigated the effect of water vapour on TENG output performance to further elucidate the practical applicability of the device.

FIG. 7 schematically shows a graph of TENG output signals based on polydimethylsiloxane 8/HKUST-19 nanocomposite films at various relative humidity conditions. As shown in fig. 7, it can be seen that the TENG output signal based on pure polydimethylsiloxane 8 decreases with increasing relative humidity, similar to conventional TENG. However, the TENG output signal based on 5 wt% HKUST-19 shows the opposite trend. It is well known that this phenomenon is unprecedented, and the output performance of TENG increases with increasing relative humidity. It is clear that as RH increases to 70%, the electrical output current of TENG based on pure polydimethylsiloxane 8 begins to decrease significantly. When RH is 90%, TENG output signal based on pure polydimethylsiloxane 8 drops to 0.6 μ a, with up to 90% loss of initial output compared to RH 10%. In contrast, the TENG output current based on 5 wt% HKUST-19 increased from 37 μ A to 54.5 μ A (i.e., the initial value increased by approximately 140%) when RH increased from 10% to 90%. This result shows that HKUST-19 can improve the performance of the generator even in a humid environment. When the content of HKUST-19 was 3 wt%, the output performance of TENG remained almost unchanged. As for TENG doped at 1 wt%, 7 wt%, 9 wt%, although the output signal also decreased with increasing RH, the magnitude of the decrease was still less than TENG without HKUST-19 doping.

Water adsorbed on the frictional surface layer plays an important role in the frictional charge. The effect of humidity on TENG output performance is attributed to: the dissipation of the charge is caused by the formation of a water layer on the surface of the negative friction layer. Table 1 shows the contact angles of the nanocomposite films with different HKUST-19 contents.

TABLE 1

As shown in table 1, it can be seen from the table that when the HKUST-19 content was increased from 0 wt% to 9 wt%, the contact angle was changed from 105 ° to 110 °, and the hydrophobicity of the nanocomposite film was not significantly changed, which means that the hydrophobicity was no longer a major factor in evaluating the humidity-dependent output performance of TENG. According to the previous report, HKUST-19 can establish adsorption-desorption equilibrium under a certain humidity environment. As RH increases, more water molecules are absorbed in the pores of HKUST-19 and vice versa. The structural change is accompanied by a distinct color shift of the nanocomposite, from deep blue to light blue. As discussed above, as the relative humidity increases, the TENG output performance also increases. This phenomenon is attributed to an increase in electron capturing ability and dielectric constant and an increase in relative humidity. When the content of HKUST-19 is 0 wt% (pure polydimethylsiloxane 8), the more water molecules are absorbed on the surface of the nanocomposite film, the more surface triboelectric charges are consumed under high humidity conditions, and therefore, the output performance of TENG based on pure polydimethylsiloxane 8 is lowered with the increase of RH, and in the case of TENG based on the nanocomposite film into which HKUST-19 is introduced, HKUST-19 can effectively trap surface triboelectric electrons inside the frictional layer.

Fig. 8 schematically shows the charge decay time of TENG as a function of relative humidity. As shown in fig. 8, it can be seen that the TENG decay time based on pure polydimethylsiloxane 8 decreases with increasing relative humidity. The decay time decreased from 130 minutes to 25 minutes as the RH increased from 10% to 90%. However, the decay time of TENG based on 5 wt% HKUST-19 showed the opposite trend. It increased from 500 minutes to 1200 minutes (i.e., 240% of the initial value), indicating that the average number of increased internal electrons was greater than the number of decreased surface electrons when the RH increased from 10% to 90%, consistent with the output performance described above. As the HKUST-19 content was further increased from 5 wt% to 9 wt%, the required decay time decreased with RH, which may be an excessively strong electron capture capacity of absorbing water HKUST-1, pushing more captured electrons to the bottom of the dielectric layer, resulting in loss of triboelectrons due to recombination with the positive charge induced on the electrode. The dependence of the decay time on RH is similar to the output performance of TENG devices.

FIG. 9 schematically shows the dielectric constant of the nanocomposite film as a function of relative humidity. As shown in fig. 9, for pure polydimethylsiloxane 8, the dielectric constant was not affected by relative humidity; the dielectric constant of the nanocomposite film comprising HKUST-19 monotonically increased with increasing RH, which is attributed to the increase in the dielectric constant of HKUST-19 with increasing RH. For HKUST-19 content 5 wt% nanocomposite films, the dielectric constant increased from 3.0 to 3.4 (i.e., 113% of the initial value) at a frequency of 1000Hz as the RH increased from 10% to 90%. When RH increases, the electron capture capacity and dielectric constant of HKUST-19 are increased by the three-dimensional pores absorbing water molecules therein, resulting in an enhanced TENG output performance. Therefore, triboelectric charge and dielectric properties play a more important role than hydrophobicity in influencing TENG output performance.

In summary, in the embodiment of the present invention, the nano composite film formed by compounding the high molecular polymer and the metal organic framework is used as the negative friction layer of the friction nano generator, and due to the introduction of the metal organic framework, even under the condition of increasing the environmental humidity, the density of the friction charge is increased and the dielectric constant of the negative friction layer is improved, so that the density of the transferred charge is increased, the output performance of the friction nano generator is increased along with the increase of the humidity, the application range of the friction nano generator is greatly widened, and the large-scale commercial application of the friction nano generator is facilitated.

The above-mentioned embodiments are intended to illustrate the objects, technical solutions and advantages of the present invention in further detail, and it should be understood that the above-mentioned embodiments are only exemplary embodiments of the present invention, and are not intended to limit the present invention, and any modifications, equivalents, improvements and the like made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. The friction nano generator is characterized in that a friction layer of the friction nano generator is composed of a nano composite film.

2. The triboelectric nanogenerator of claim 1, wherein the nanocomposite film is compounded from a high molecular polymer and a metal organic framework.

3. The triboelectric nanogenerator of claim 2, wherein the high molecular polymer is at least one of polyvinylidene fluoride, polydimethylsiloxane, polytetrafluoroethylene, or polyvinyl chloride, and the metal-organic framework is at least one of UiO-66, HKUST-1, ZIF-8, or MIL-101.

4. The triboelectric nanogenerator according to claim 3, wherein the UO-66 is prepared from zirconium chloride as a metal salt and terephthalic acid as an organic ligand, the HKUST-1 is prepared from copper nitrate as a metal salt and trimesic acid as an organic ligand, the ZIF-8 is prepared from zinc nitrate as a metal salt and 2-methylimidazole as an organic ligand, and the MIL-101 is prepared from chromium nitrate as a metal salt and terephthalic acid as an organic ligand.

5. The triboelectric nanogenerator according to claim 1, wherein the nanocomposite film is compounded from polydimethylsiloxane (8) and HKUST-1 (9).

6. The triboelectric nanogenerator according to claim 5, wherein the mass of HKUST-1(9) is 1 to 10 wt% of the mass of the nanocomposite film.

7. The triboelectric nanogenerator according to any of claims 1-6, wherein the triboelectric nanogenerator is of a vertical contact-separation type, a sliding type, a single electrode type and an independent tribolayer type.

8. The triboelectric nanogenerator according to claim 7, wherein the triboelectric nanogenerator is of a vertical contact-separation type comprising:

an upper electrode (2);

a positive friction layer (3) formed on the surface of the upper electrode (2);

a lower electrode (5);

the negative friction layer (4) is formed on the surface of the lower electrode (5), and the negative friction layer (4) is formed by the nano composite film;

the upper electrode (2) is connected with the lower electrode (5) through an external circuit (7), and the positive friction layer (3) is opposite to the negative friction layer (4) in position and can be mutually contacted and separated.

9. The triboelectric nanogenerator of claim 8, further comprising:

an upper substrate (1); the upper electrode (2) is formed on the surface of the upper substrate (1);

and/or, the device also comprises a lower substrate (6), and the lower electrode (5) is formed on the surface of the lower substrate (6).

10. A triboelectric nanogenerator according to claim 9, wherein the thickness of the tribolayer of the nanocomposite film ranges from 100 to 500 microns.