KR102140147B1 - Heterogeneous laminate comprising graphene, preparing method thereof, thermoelectric material, thermoelectric module and thermoelectric apparatus comprising same - Google Patents

Abstract

A composite laminate comprising graphene and a thermoelectric inorganic material, which is a self-assembled structure in which ionic bonds are formed between the graphene and the thermoelectric inorganic material, and a method for manufacturing the same are provided. In addition, it provides a thermoelectric material including the composite laminate, a thermoelectric device including the same, a thermoelectric module including the thermoelectric device, and a thermoelectric device including the same.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention Heterogeneous laminate comprising graphene, preparing method thereof, thermoelectric material, thermoelectric module and thermoelectric apparatus comprising same}

A graphene-containing composite laminate, a method of manufacturing the same, a thermoelectric material including the same, a thermoelectric module and a thermoelectric device are presented.

Thermoelectric phenomenon refers to the reversible and direct energy conversion between heat and electricity, and a phenomenon in which current flow or voltage occurs due to diffusion movement of electrons or holes due to temperature gradients generated inside the material. to be. The Peltier effect applied to the cooling field by using the temperature difference at both ends formed by the current applied from the outside and the Seebeck effect applied to the power generation field by using the electromotive force generated from the temperature difference between both ends of the material. It is distinguished.

The thermoelectric material is a passive cooling system and is being applied as an active cooling system for semiconductor equipment and electronic equipment, which is difficult to solve the heat generation problem, and demand in cooling applications that cannot be solved with a conventional refrigerant gas compression system is increasing. Thermoelectric cooling is a vibration-free, low-noise, eco-friendly cooling technology that does not use refrigerant gases that cause environmental problems.If the thermoelectric cooling efficiency is improved by developing high-efficiency thermoelectric cooling materials, it will expand its application to general-purpose cooling fields such as refrigerators and air conditioners. I can.

In addition, when thermoelectric power generation materials are applied to parts where heat is emitted from automobile engines and industrial plants, power generation is possible due to the temperature difference occurring at both ends of the material, and thus it is attracting attention as one of the renewable energy sources.

One aspect is to provide a composite laminate containing graphene and a thermoelectric inorganic material with improved thermoelectric conversion efficiency.

Another aspect provides a thermoelectric material including the composite laminate.

Another aspect provides a thermoelectric device including the thermoelectric material.

Another aspect provides a thermoelectric module including the thermoelectric element.

Another aspect provides a thermoelectric device including the thermoelectric module.

Another aspect is to provide a method of manufacturing the composite laminate.

According to one aspect, there is provided a composite laminate comprising graphene and a thermoelectric inorganic material, which is a self-assembled structure in which ionic bonds are formed between the graphene and the thermoelectric inorganic material.

According to another aspect, a thermoelectric material including a composite laminate is provided.

According to another aspect, a thermoelectric device including the thermoelectric material is provided.

According to another aspect, a first electrode;

A second electrode; And

A thermoelectric module is provided that is interposed between the first electrode and the second electrode and includes the thermoelectric element.

Heat source according to another aspect; And

A thermoelectric element absorbing heat from the heat source;

A first electrode disposed to contact the thermoelectric element; And

A thermoelectric module disposed to face the first electrode and having a second electrode in contact with the thermoelectric element; and

A thermoelectric device is provided in which the thermoelectric element includes the thermoelectric material described above.

According to another aspect, mixing graphene and a first ionic surfactant to obtain a graphene-containing mixture;

i) a thermoelectric inorganic material and having a polarity different from that of the first ionic surfactant

Mixing with a second ionic surfactant to obtain a mixture containing a thermoelectric inorganic substance or ii) obtaining a mixture containing a thermoelectric inorganic substance using a thermoelectric inorganic substance doped with an interhalogen compound; And

Including, mixing and reacting the graphene-containing mixture and the thermoelectric-inorganic-containing mixture

There is provided a method of manufacturing a composite laminate comprising graphene and a thermoelectric inorganic material, and obtaining a self-assembled structure in which an ionic bond is formed between the graphene and the thermoelectric inorganic material.

Obtaining the graphene-containing mixture, obtaining the thermoelectric inorganic substance-containing mixture; When performing one or more steps selected from the steps of mixing the graphene-containing mixture and the thermoelectric-inorganic-containing mixture, ultrasonic waves may be applied.

According to another aspect, including graphene and a thermoelectric inorganic material, a first ionic surfactant is bonded to the graphene,

The thermoelectric inorganic material is bound with a second ionic surfactant having a polarity different from the first ionic surfactant or doped with an interhalogen compound,

A composite laminate is provided that is a self-assembled structure in which an ionic bond is formed between the graphene and the thermoelectric inorganic material.

The thermoelectric material according to exemplary embodiments may exhibit improved thermoelectric conversion efficiency as the Seebeck coefficient and electrical conductivity increase. Thermoelectric devices, thermoelectric modules, and thermoelectric devices including the thermoelectric material may be usefully used in general-purpose cooling devices such as refrigerant-free refrigerators and air conditioners, waste heat power generation, thermoelectric nuclear power generation for military aerospace, and micro cooling systems.

1 shows a schematic diagram of a composite laminate according to an embodiment.
2 is a schematic diagram showing a process of forming a composite laminate according to an embodiment.
3 is a schematic diagram of a thermoelectric module according to an embodiment.
4A is a schematic diagram showing thermoelectric cooling by the Peltier effect.
4B is a schematic diagram showing thermoelectric power generation by the Seebeck effect.
5A shows an XRD (X-ray diffraction) analysis of the Sb ₂ Te ₃ nanoplate prepared according to Preparation Example 6. FIG.
5B shows the results of XRD (X-ray diffraction) analysis of Samples 1 to 3 and Raw Sb ₂ Te ₃ according to Evaluation Example 1. FIG.
6A is an electron scanning microscope photograph of the Sb ₂ Te ₃ nanoplate obtained according to Preparation Example 6. FIG.
6B is an electron scanning microscope photograph of a composite laminate obtained according to Example 2. FIG.
6C is an electron scanning microscope photograph of the composite laminate obtained in Example 1. FIG.
6D is a SEM (Scanning Election Microscopy) photograph of the graphene/Sb ₂ Te ₃ blend of Comparative Example 1.
7 is a view showing the results of HRTEM/SAED (High-resolution transmission electron microscopy)/SAED (selected area electron diffraction) analysis of the composite laminate obtained in Preparation Example 6. FIG.
8 shows a Raman spectrum of the Sb ₂ Te ₃ nanoplate obtained in Preparation Example 6.
9 is a diagram showing the zeta potential of the composite laminate obtained in Example 1. FIG.
10 is a schematic view schematically showing the structure of a spark plasma sintering apparatus.

Hereinafter, a graphene-containing composite laminate, a method of manufacturing the same, a thermoelectric material including the same, a thermoelectric module, and a thermoelectric device according to an exemplary embodiment will be described.

The composite laminate according to an embodiment includes graphene and a thermoelectric inorganic material, and is a self-assembled structure in which ionic bonds are formed between the graphene and the thermoelectric inorganic material.

According to another embodiment, a first ionic surfactant is bonded to the graphene, and a second ionic surfactant having a polarity different from that of the first ionic surfactant is bonded to the thermoelectric inorganic material, or a halogen It provides a composite laminate that is a self-assembled structure doped with a liver compound and an ionic bond formed between the graphene and the thermoelectric inorganic material.

The ionic bond refers to, for example, an electrostatic attraction.

In the composite laminate, the graphene and the thermoelectric inorganic material have surface charges of opposite polarities, and the two materials are bonded to each other by an electrostatic attraction between them. In this way, the heterogeneous composite obtained by combining graphene and a thermoelectric inorganic material by electrostatic attraction exhibits improved thermoelectric change efficiency compared to the case of using a conventional thermoelectric inorganic material.

The thermoelectric material according to an embodiment includes graphene and a thermoelectric inorganic material, and includes a composite laminate that is a self-assembled structure in which ionic bonds are formed between the graphene and the thermoelectric inorganic material. Such a composite laminate can be obtained by forming a thermoelectric inorganic material, for example, a thermoelectric inorganic material in the form of a thin film on graphene having a planar structure. Such a laminate can form a multi-layered laminate by alternately laminating graphene and a thermoelectric inorganic material. 1, it can be seen that the graphene 1 and the thermoelectric inorganic material 2 are repeatedly stacked three times. The graphene 1 and the thermoelectric inorganic material 2 may be stacked repeatedly, for example, 1 to 100 times.

The stacked composite of graphene and thermoelectric inorganic material is prepared by self-assembly of graphene and thermoelectric inorganic material having different surface charges.

2 is a schematic diagram showing the structure of a laminated composite according to an embodiment.

Referring to this, the table of graphene in the form of a plate-like laminate and Sb ₂ Te _{3 which} is a thermoelectric inorganic material

If the surface charge is treated to have positive or negative ions and the graphene and the thermoelectric inorganic material have surface charges with opposite polarities, electrostatic attraction, which is an ionic bond, acts between them to form a self-assembled structure. The laminated composite is completed.

The surface charge of the graphene can be controlled using an ionic surfactant, and the surface charge of the thermoelectric inorganic material can be controlled using an ionic surfactant or an interhalogen compound.

In the composite laminate, the thermoelectric inorganic material has a single crystal structure.

The thermoelectric inorganic material is, for example, a particle having a horizontal axis length of 0.01 to 10 μm and a thickness of 1 to 100 nm of a hexagonal crystal system.

The thermoelectric inorganic material can be used without limitation as long as it is a material available in the art.

For example, at least one element selected from the group consisting of a transition metal, a rare earth element, a group 13 element, a group 14 element, a group 15 element, and a group 16 element may be used.

Y, Ce, La, etc. may be used as the rare earth elements, and Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, W, Mn, Fe, Co, Ni, Cu, Zn, Ag , One or more of Re may be used, one or more of B, Al, Ga, In may be used as the group 13 element, and one or more of C, Si, Ge, Sn, and Pb may be used as the group 14 element. In addition, one or more of P, As, Sb, and Bi may be used as the group 15 element, and one or more of S, Se, and Te may be used as the group 16 element. For example, among the above elements, one or more thermoelectric inorganic materials including two or more elements may be used.

Examples of thermoelectric inorganic substances containing such elements include Bi-Te, Bi-Se, Co-Sb, Pb-Te, Ge-Tb, Si-Ge, Bi-Sb-Te, Sb-Te Thermoelectric inorganic materials, such as system, Sm-Co system, and transition metal silicide system, can be used. These thermoelectric inorganic materials may include one or more elements selected from the group consisting of the transition metal, rare earth element, group 13 element, group 14 element, group 15 element, and group 16 element as a dopant to improve electrical properties.

Bi-Te-based thermoelectric inorganic materials may include (Bi,Sb) ₂ (Te, Se) ₃ -series thermoelectric inorganic materials in which Bi ₂ Te ₃ or Sb and Se are used as dopants, and Bi-Se thermoelectric inorganic materials are Bi ₂ Se ₃ Etc. can be illustrated.

As the Co-Sb-based thermoelectric inorganic material, a CoSb _3- based thermoelectric inorganic material may be exemplified, and as the Sb-Te-based thermoelectric inorganic material, Sb ₂ Te ₃ , AgSbTe ₂ , and CuSbTe ₂ may be exemplified, and PbTe, (PbTe) _m AgSbTe ₂ etc. can be illustrated.

For example, at least one selected from Bi ₂ Te ₃ , Sb ₂ Te ₃ and Bi ₂ Se ₃ may be mentioned.

The thermoelectric inorganic material has a thin film structure. The thickness of the thin film is 1 to 100 nm.

That the thermoelectric inorganic material is a single crystal structure can be confirmed through high-resolution transmission electron microscopy (HRTEM)-selected area electron diffraction (SAED) analysis. Specifically, it can be seen that the thermoelectric inorganic material is a well crystallized single crystal through SAED.

When the thermoelectric inorganic material is Sb ₂ Te ₃ , the plane spacing is 0.19 to 0.23 nm, for example, 0.21 nm through HRTEM, which is on the (110) lattice plane of Sb ₂ Te ₃ Corresponds.

When the thermoelectric inorganic substance is Sb ₂ Te ₃ , the Raman analysis spectrum of this compound

At 90±1, 119.8±0.8, 139.6±1, 251.3±0.3, and 450±1 cm ^-1 , the peaks were shown, and the peaks were related to the Sb ₂ Te ₃ thin film, indicating a thin plate structure. For example, 119.8 ± 0.8, 251.3 ± 0.3, 450 ± 1 cm -1 peak is a peak associated with semiconductor characteristics, a peak (peak A) and 251.3 ± 0.3 cm appearing in the 119 ± 0.8cm ^{-1 -} peak appearing at ¹ The intensity ratio of (Peak B) (Peak A/Peak B) is 2.5 to 2.9, for example about 2.8.

The stacked composite of graphene and thermoelectric inorganic as described above is a thin plate-shaped structure.

Thermal conductivity due to phonon scattering at the improved interface is reduced and charge mobility over a large area

High electrical conductivity can be obtained by increasing. Therefore, it has improved thermoelectric performance

It can be usefully used for thermoelectric devices, thermoelectric modules, or thermoelectric devices.

Graphene constituting the composite laminate is a material having high conductivity and mobility, and when the laminate is formed by applying it to a thermoelectric inorganic material, the thermoelectric performance of the thermoelectric inorganic material is improved due to the excellent electrical properties of graphene. .

The performance of the thermoelectric material uses the ZT value of Equation 1 below, which is collectively referred to as a dimensionless figure of merit.

<Equation 1>

ZT = (S ² σT) / k

In the formula, ZT is the figure of merit, S is the Seebeck coefficient, σ is the electrical conductivity, T is the absolute temperature, and κ is the thermal conductivity.

As shown in Equation 1, in order to increase the ZT value of the thermoelectric material, the Seebeck coefficient and electrical conductivity, that is, the power factor (S ² σ) must be increased and the thermal conductivity must be decreased.

Graphene is a material that forms a honeycomb-shaped two-dimensional planar structure in which carbon is connected to each other in a hexagonal shape, and has excellent electrical properties due to excellent charge mobility. In the case of heat conduction characteristics, in the out-of-plane direction of graphene (direction perpendicular to the planar structure of graphene), the movement of the phonon is blocked due to scattering, so that the heat conduction characteristic is in the in-plane direction (within the ) Can be lowered. Therefore, when the properties of in-plane or out-of-plane graphene are applied to a thermoelectric material, high electrical conductivity and low thermal conductivity are realized, so that the performance of the thermoelectric material can be improved.

Graphene used in the graphene-containing thermoelectric material is that a plurality of carbon atoms are covalently linked to each other to form a polycyclic aromatic molecule, and the carbon atoms connected by the covalent bond form a 6-membered ring as a basic repeating unit, It is also possible to further include a 5-membered ring and/or a 7-membered ring. As a result, the graphene appears as a single layer of carbon atoms (usually sp ² bonds) covalently bonded to each other. The graphene may be made of a single layer, but it is also possible to form a plurality of layers by stacking several of them, for example, 1 to 300 layers, or 2 to 100 layers, or 3 to 50 layers. Can have. In the case of multi-layered graphene, phonons are scattered due to the influence of the interlayer interface, so that superior thermoelectric performance can be obtained in the out-of-plane direction.

On the other hand, when the graphene is a multilayer, it may have various stacked structures, for example, the stacked structure may have an AB-stacking structure or a random-stacking structure. The structure may have more advantageous properties than the AB laminated structure in terms of blocking phonon in the out-of-plane direction, carrier mobility, and electrical conductivity.

The graphene is not particularly limited, and can be produced by various production methods, for example, it can be produced by a peeling process or a growth process.

The thermoelectric inorganic material as described above may form a laminate by directly laminating the thermoelectric inorganic material in the form of a thin film on the graphene.

When a thermoelectric inorganic material having a single crystal structure is formed on graphene, the peeled thermoelectric inorganic material nanoparticles can be used, and after securing a thermoelectric inorganic material thin film having a single crystal structure by applying a synthesis, tape peeling or ultrasonic dispersion peeling process, It can be formed by laminating on graphene.

The crystal orientation of the thermoelectric inorganic thin film formed on the graphene can be measured through XRD (X-Ray Diffraction), and their crystal orientation through the measurement result of XRD may have a value of (00ℓ) ( The ℓ is an integer having a range of 1 to 99).

The crystal orientation of (00ℓ) of such a thermoelectric inorganic thin film improves various physical properties in the out-of-plane direction shown in FIG. 1. That is, as the thermoelectric inorganic thin film is formed with a certain orientation on graphene, the crystallinity and electronic structure at the interface between graphene having metallic properties and thermoelectric inorganic materials having semiconductor properties change, increasing the Seebeck coefficient, and It is possible to induce an increase in electrical conductivity and charge mobility by accelerating the transfer. In addition, phonon scattering at the interface between the graphene and the thermoelectric inorganic material increases, so that thermal conductivity can be controlled. In addition, by forming the thermoelectric inorganic material on a nanoscale, a quantum confinement effect may be induced, and thermal conductivity may be reduced due to a phonon confinement (Phonon Glass Electron Crystal (PGEC) concept) in a nano thin film.

The quantum confinement effect is a concept that increases the effective mass by increasing the density of state of carriers in the material, thereby increasing the Seebeck coefficient without significantly changing the electrical conductivity, thereby destroying the tradeoff between the electrical conductivity and the Seebeck coefficient. , The PGEC concept is a concept in which only thermal conductivity is reduced by blocking the movement of the phonon responsible for heat transfer and not interfering with the movement of the carrier.

As described above, the out-of-plane direction shown in FIG. 1 is a space concept that is distinct from the in-plane direction of graphene having a planar structure, and refers to a direction (z-axis) perpendicular to the plane (xy-axis). . In such an out-of-plane direction, a crystalline thermoelectric inorganic material may be stacked.

The stacked composite of graphene and thermoelectric inorganic is obtained by laminating a thin film of thermoelectric inorganic material on graphene, and in this case, the stacked body may have a superlattice structure. Such a regular grid structure refers to a structure in which graphene and a thermoelectric inorganic thin film are sequentially repeated with each other.

The laminated composite of graphene and thermoelectric inorganic is obtained by laminating a thin film of thermoelectric inorganic material on graphene, and this may be repeated to form a laminated composite having a multilayer structure. That is, after forming a thermoelectric inorganic material thin film on graphene, the graphene/thermoelectric inorganic material is converted into one unit by repeating the process of forming a thermoelectric inorganic material layer on the thermoelectric inorganic material film several times after laminating the graphene again on the thermoelectric inorganic material thin film. It is possible to form a laminated composite. In the laminated composite, the graphene/thermoelectric inorganic unit may be included in a range of 1 to 100 units, for example.

In the stacked composite of graphene and the thermoelectric inorganic material, a p-type or n-type material may be used as the thermoelectric inorganic material, and the graphene may be doped with a p-dopant or an n-dopant.

The stacked composite of graphene and thermoelectric inorganic is not particularly limited in size and thickness.

Graphene according to an embodiment can be prepared by the following method.

As a method of forming graphene on a substrate, graphene obtained according to a growth process known in the art or a graphene peel obtained by a peeling process may be used. For example, graphene having a single crystal or polycrystalline structure, Alternatively, graphene grown epitaxially can be used without limitation. Such graphene may have a number of layers of 1 to 300 layers, for example.

The exfoliation process, which is an example of producing the graphene, is mechanical means (for example, scotch tape) or oxidation-reduction from a material containing a graphene structure internally, such as graphite or highly oriented pyrolytic graphite (HOPG; Highly Oriented Pyrolytic Graphite). An example is a method of separating graphene using a process.

In the exfoliation process, which is another example of manufacturing the graphene, by applying microwaves to a graphite intercalated compound (GIC), expanded graphite is obtained, and a liquid phase exfoliation process of dispersing it in a solvent is selectively performed. It is to manufacture the pin. Graphene obtained according to this method has excellent thermoelectric properties because there is no defect and no fear of oxidation.

As the solvent, N-methyl pyrrolidone or the like is used, and ultrasonic waves are used for the dispersion. And the process of dispersing in the solvent is carried out for, for example, 0.5 to 30 hours.

The GIC is an interlayer insert inserted into graphite. The intercalation can be, for example, sulfuric acid, chromic acid or mixtures thereof.

The microwave has an output of 50 to 1500W and a frequency of 2.45 to 60 GHz. The time to apply the microwave varies depending on the frequency of the microwave, but the microwave is applied for 10 to 30 minutes, for example.

In the growth process, which is an example of manufacturing the graphene, carbon adsorbed or contained in an inorganic material, for example, silicon carbide, is grown on the surface of the inorganic material at a high temperature, or a gaseous carbon source at a high temperature, for example, For example, it may include a method of forming a graphene crystal structure by dissolving or adsorbing methane, ethane, and the like in a catalyst layer, for example, a nickel, copper thin film, and then crystallizing it on the surface of the catalyst layer through cooling. Graphene obtained by such a method can be formed in a large area of 1 cm ² or more, and its shape can be uniformly manufactured, and the type and thickness of the substrate or catalyst, reaction time, cooling rate, concentration of reaction gas, etc. You can freely adjust the number of floors by adjusting. As a result, graphene obtained using the growth process has the advantage of excellent reproducibility and easy mass production. As such a growth process, any method known in the art may be used without limitation.

According to an embodiment, the graphene may be prepared according to chemical vapor deposition.

Examples of the substrate on which the graphene is formed include an inorganic substrate including at least one of a Si substrate, a glass substrate, a GaN substrate, and a silica substrate; Or a metal substrate including at least one selected from Ni, Co, Fe, Pt, Pd, Au, Al, Cr, Cu, Mn, Mo, Rh, Ir, Ta, Ti, W, U, V, and Zr substrates; Etc. can be used.

After the graphene is formed on the substrate as described above, a thermoelectric inorganic thin film is formed on the graphene. Such a thermoelectric inorganic thin film is formed using a thermoelectric inorganic thin film obtained by exfoliating the thin film from a particulate thermoelectric inorganic substance or a thermoelectric inorganic composite obtained by synthesizing.

Hereinafter, a method of manufacturing a composite laminate using the above-described graphene and thermoelectric inorganic material will be described.

Graphene is mixed with a first ionic surfactant to obtain a graphene-containing mixture. The mixture may be subjected to ultrasonic treatment to obtain graphene to which a first ionic surfactant having a positive or negative surface charge is bound.

The graphene may be a graphene exfoliated product.

The ultrasonic waves are applied at a frequency of 2.45 to 60 KHz and an output condition of 50 to 1500 W.

Separately, a mixture containing a thermoelectric inorganic substance is obtained by mixing a thermoelectric inorganic substance and a second ionic surfactant having a polarity different from that of the first ionic surfactant, or a mixture containing a thermoelectric inorganic substance using a thermoelectric inorganic substance doped with an interhalogen compound. Get

When the mixture of the thermoelectric inorganic material and the second ionic surfactant is subjected to ultrasonic waves, a thermoelectric inorganic compound compound in which the second ionic surfactant is combined may be obtained.

The ultrasonic wave is applied at a frequency of 2.45 to 60 KHz and an output condition of 50 to 1500 W.

The first ionic surfactant and the second ionic surfactant are composed of a hydrophobic tail group and a hydrophilic head group.

The thermoelectric inorganic material doped with the interhalogen compound is controlled to have a different polarity from the graphene exfoliated material to which the first ionic surfactant is bonded.

Thereafter, when the graphene-containing mixture and the thermoelectric inorganic substance-containing mixture are mixed and reacted, a composite laminate containing graphene and a thermoelectric inorganic substance, and a self-assembled structure having an ionic bond formed between the graphene and the thermoelectric inorganic substance can be obtained. .

The reaction is accomplished by performing ultrasonic treatment. The sonication is sonic for example

For example, it may be performed using a sonic tip (SONIC VX-750 ultrasonic processor with a flate head tip), and the ultrasonic wave may be performed under, for example, a frequency of 2.45 to 60 KHz and an output condition of 50 to 1500 W.

The ultrasonic treatment time varies depending on ultrasonic conditions such as ultrasonic power, and may be performed for, for example, 10 minutes to about 30 minutes.

The first ionic surfactant and the second ionic surfactant used in the preparation process are, as non-limiting examples, polydiallyldimethylammonium chloride (PDDA), sodium dodecyl sulfate (SDS), cetyltrimethylammonium bromide (CTAB). ), trimethylammonium bromide (TTAB), sodium cholate (SC), sodium deoxycholate (DOC), sodium taurodeoxycholate (TDOC). I can.

The content of the first ionic surfactant is 100 to 2000 parts by weight based on 100 parts by weight of the graphene exfoliated product.

The content of the second ionic surfactant is 100 to 2000 parts by weight based on 100 parts by weight of the thermoelectric inorganic material. The thermoelectric inorganic material may be a thermoelectric inorganic material exfoliating product or a thermoelectric inorganic material composite.

When the content of the first ionic surfactant and the second ionic surfactant is within the above range, the electrostatic attraction between graphene and the thermoelectric inorganic material is excellent.

According to an embodiment, the first ionic surfactant is polydiallyldimethylammonium chloride (PDDA), and the second ionic surfactant is SDS.

The thermoelectric inorganic material can be obtained by mixing a particulate thermoelectric inorganic material with an interlayer insert, inserting it between the layers of the thermoelectric inorganic material, and removing the interlayer insert. Here, an interhalogen compound is used as the intercalation material, and examples thereof include IBr and ICl.

In the case of using an inter-halogen compound as an interlayer insert, the process of exfoliating the thermoelectric inorganic material will be described in more detail.

The mixture of the particulate thermoelectric inorganic material and the interhalogen compound is placed in a sealed container and subjected to a first heat treatment at 70 to 130°C. The interhalogen compound is a sublimable substance and penetrates between the particles of the thermoelectric inorganic substance in a solid state.

Take out the thermoelectric inorganic material in which the inter-halogen compound is inserted between the layers from the sealed container and perform secondary heat treatment at 200 to 250°C. Subsequently, the inter-halogen compound is removed from the result of the secondary heat treatment to weaken the interlayer bonding force of the thermoelectric inorganic material to increase the interlayer distance, thereby facilitating peeling.

The process of removing the interhalogen compound from the result of the secondary heat treatment may use a solvent such as acetone.

Subsequently, when the thermoelectric inorganic material from which the interhalogen compound is removed is subjected to ultrasonic treatment, a thermoelectric inorganic material exfoliated product having a thickness of 1 to 100 nm, for example, 30 to 40 nm, may be obtained.

The ultrasonic treatment is performed at a frequency of 2.45 to 60 kHz and an output range of 50 to 1500 W. And the ultrasonic treatment can be carried out in the presence of water.

If the process of removing the interhalogen compound from the result of the secondary heat treatment is omitted, a thermoelectric inorganic material doped with the interhalogen compound may be obtained. The thermoelectric inorganic material doped with the interhalogen compound can be used as the aforementioned thermoelectric inorganic material exfoliating product.

Hereinafter, a mechanism by which ionic bonds are formed between graphene (eg, a graphene exfoliated product) and a thermoelectric inorganic material (eg, a thermoelectric inorganic compound or exfoliated product) will be described according to an embodiment, but limited to the mechanism described below. It is not.

The hydrophobic tail group of the first ionic surfactant is disposed adjacent to the graphene having hydrophobicity and bonded to the graphene, and the hydrophilic head group of the first ionic surfactant is disposed far from the graphene. At this time, the hydrophilic head group has a positive or negative charge.

In the thermoelectric inorganic material, as in the case of graphene, the hydrophobic tail group of the second ionic surfactant is bonded to the thermoelectric inorganic material, and the hydrophilic head group of the second ionic surfactant is located away from the thermoelectric inorganic material. The hydrophilic group may have a negative or positive charge.

When the hydrophilic head group disposed from the far side of the graphene has a positive charge, the hydrophilic head group disposed on the far side from the thermoelectric weapon is controlled to take a negative charge, and between the graphene and the thermoelectric inorganic material by the electrostatic attraction therebetween Ionic bonds are formed in

The thermoelectric inorganic material may have a single crystal structure. In addition, the thermoelectric inorganic material may have a p-type semiconductor property or an n-type semiconductor property.

The manufacturing method of the composite laminate according to the embodiment is not only easy to manufacture, but also has a short reaction time and enables mass production. In addition, the composite laminate may be manufactured in the form of a bulk composite through a sintering process such as a spark plasma sintering process.

In the spark plasma sintering process, bulk pellets are manufactured by pressure sintering under high temperature and high pressure conditions using the spark plasma sintering apparatus of FIG. 10. The bulk pellet process using the spark plasma sintering process will be described in more detail as follows.

The DC pulse current supplied from the power supply device 100 is applied to the upper and lower punch electrodes 112 of the graphite pressurizing die 111 in the vacuum chamber 114 to initiate heating by spark discharge between the composite powder 113 And with the help of the spark discharge pressure, mass transfer is promoted to obtain a bulk pellet, which is a compact compact.

The high pressure is 300 to 450° C., for example about 390° C., and the high pressure is in the range of 70 to 85 MPa, for example.

The graphene/thermoelectric-inorganic composite laminate obtained through the process as described above has crystallinity at the interface of graphene having metallic properties and thermoelectric inorganic materials having semiconductor properties as the thermoelectric inorganic thin film is formed with a certain orientation on graphene. And the electronic structure is changed to increase the Seebeck coefficient, and the transfer of charged particles is accelerated to induce an increase in electrical conductivity and charge mobility. In addition, phonon scattering at the interface between the graphene and the thermoelectric inorganic material increases, so that thermal conductivity can be controlled. In addition, by forming the thermoelectric inorganic material on a nanoscale, a quantum confinement effect may be induced, and thermal conductivity may be reduced due to phonon confinement (Phonon Glass Electron Crystal (PGEC) concept) in a nano thin film.

The graphene/thermoelectric-inorganic composite laminate having the improved thermoelectric performance as described above can be usefully used as a thermoelectric material. Accordingly, the thermoelectric material containing the graphene/thermoelectric inorganic composite laminate may be molded by a method such as cutting to manufacture a thermoelectric device. The thermoelectric element may be a p-type thermoelectric element. Such a thermoelectric device means that the thermoelectric material is formed in a predetermined shape, for example, a rectangular parallelepiped shape.

Meanwhile, the thermoelectric device may be a component capable of exhibiting a cooling effect by being combined with an electrode and applying a current, and exhibiting a power generation effect by a device or temperature difference.

2 shows an example of a thermoelectric module employing the thermoelectric element. As shown in FIG. 2, the upper insulating substrate 11 and the lower insulating substrate 21 are formed by patterning an upper electrode 12 (first electrode) and a lower electrode 22 (second electrode). The p-type thermoelectric component 15 and the n-type thermoelectric component 16 are in contact with each other between the upper electrode 12 and the lower electrode 22. These electrodes 12 and 22 are connected to the outside of the thermoelectric element by a lead electrode 24. As the p-type thermoelectric component 15, the thermoelectric element described above may be used. As the n-type thermoelectric component 16, any one known in the art may be used without limitation.

As the insulating substrates 11 and 21, gallium arsenide (GaAs), sapphire, silicon, Pyrex, quartz substrates, or the like can be used. Materials of the electrodes 12 and 22 may be variously selected, such as copper, aluminum, nickel, gold, titanium, and the like, and their sizes may also be variously selected. As a method of patterning these electrodes 12 and 22, a conventionally known patterning method may be used without limitation, and for example, a lift-off semiconductor process, a vapor deposition method, a photolithography method, or the like may be used.

In one embodiment of the thermoelectric module, as shown in FIGS. 3 and 4, one of the first electrode and the second electrode may be exposed to a heat source. In one embodiment of the thermoelectric element, one of the first electrode and the second electrode is electrically connected to a power supply source, or external to the thermoelectric module, for example, an electric device that consumes or stores power (for example, a battery) Can be electrically connected to

As an embodiment of the thermoelectric module, one of the first electrode and the second electrode may be electrically connected to a power supply source.

Hereinafter, the present invention will be described in more detail with reference to examples, but the present invention is not limited thereto.

Manufacturing example One: Graphene Exfoliated Produce

EG (Expanded graphite) was prepared by applying microwave (output: 700W, frequency: 2.45 GHz) to 4 mg of GIC (Graphite intercalation compound) (Hyundai Coma, HCE-995270) for 1 minute.

Manufacturing example 2: Sb ₂ Te ₃ Nano plate ( nanoplate )

After mixing 0.5 g of Sb ₂ Te ₃ (Alfa Asear) powder and 1 g of IBr (Iodine bromide), put it in a container, block the container from the outside, and keep the inside of the container at about 127°C for 48 hours to sublimate IBr particles Was reacted to penetrate between solid state Sb ₂ Te ₃ thermoelectric inorganic particles. After removing the resulting powder from the blocked container, reacting it at 220° C. for 5 hours, washing with acetone to remove the IBr particles penetrating between the inorganic particles, weakening the bonding force between the layers of Sb ₂ Te ₃ and increasing the distance to prevent peeling. Made it easy.

15 mg of the resulting particles were mixed with 30 ml of distilled water, and ultrasonic waves (a frequency of 20 kHz and an output of 540 W) were added for 90 minutes to prepare a Sb ₂ Te ₃ nanosheet having a thickness of about 30 nm.

Manufacturing example 3: Sb ₂ Te ₃ Nano plate ( nanoplate )

Except for using ICl (Iodine chloride) instead of IBr (Iodine bromide), it was carried out in the same manner as in Preparation Example 2 to prepare a Sb ₂ Te ₃ nanoplate having a thickness of about 30 nm.

Manufacturing example 4: Sb ₂ Te ₃ Preparation of nanoplate

Except for changing the reaction temperature of 0.5 g of Sb ₂ Te ₃ (Alfa asear) powder and 1 g of IBr (Iodine bromide) from 127° C. to 78° C., it was carried out according to the same method as in Preparation Example 2 to about (30) nm To prepare a thick Sb ₂ Te ₃ nanosheet (nanosheet).

Manufacturing example 5: IBr Doped Sb ₂ Te ₃ Nano plate ( nanoplate )

After mixing 0.5 g of Sb ₂ Te ₃ (Alfa Asear) powder and 1 g of IBr (Iodine bromide), put it in a container, block the container from the outside, and keep the inside of the container at about 127°C for 48 hours to sublimate IBr particles Was reacted to penetrate between solid state Sb ₂ Te ₃ thermoelectric inorganic particles.

The resulting powder was removed from the blocked container and reacted at 220° C. for 5 hours to weaken the bonding force between the layers of Sb2Te3 and widen the distance to facilitate peeling. 15 mg of the resulting particles were mixed with 30 ml of distilled water, and ultrasonic treatment was performed for 90 minutes at a frequency of 20 kHz and an output condition of 540 W to prepare an IBr-doped Sb ₂ Te ₃ nanoplate having a thickness of about 30 nm.

Manufacturing example 6: using a synthetic process Sb2Te3 Nano plate ( nanoplate )

1 g of tellurium (Te) powder and 10 ml of tri-n-octylphosphine (TOP) were placed in a Teflon lined stainless-steel autoclave container, and microwave-solvent heat (microwave -assisted solvothermal) (microwave output: 1200 W, frequency 2.45 GHz) was treated with an equipment (MARS5) at 220° C. for 2 minutes to prepare a yellow solution, Te-TOP solution.

A mixture of 25 ml of 1,5-pentanediol and 1 g of SbCl ₃ was mixed for about 15 minutes in a bath sonication (ultrasonic frequency of 40 kHz, output 400 W) to prepare a transparent SbCl ₃ -pentanediol solution.

Te-TOP 10ml solution, SbCl ₃ -pentanediol solution and thioglycolic acid (TGA) 500µl are placed in a Teflon lined stainless-steel autoclave container and synthesized by microwave solvent heat A device (microwave-assisted solvothermal) (MARS5, CEM Corporation) (microwave output: 1200 W, frequency of 2.45 GHz) was placed and treated at 220° C. for 30 seconds. After washing the obtained powder with acetone, it was dried in a vacuum oven at 200° C. for 5 hours to obtain a Sb ₂ Te ₃ nanoplate.

Example One: Graphene - Sb ₂ Te ₃ complex Laminated Produce

4 mg of EG, a graphene exfoliated product obtained according to Preparation Example 1, 150 mg of polydiallyldimethylammonium chloride (PDDA), and 30 ml of distilled water were mixed, and a sonic tip (SONIC VX-750 ultrasonic processor with a flate head tip) was used. A graphene exfoliated product with positively charged PDDA was prepared by performing ultrasonic treatment for about 90 minutes at an output of about 5400W and a frequency of 20 kHz.

Separately, 15 mg of the Sb ₂ Te ₃ nanoplate obtained according to Preparation Example 6, 150 mg of sodium dodecyl sulfate (SDS), and 30 ml of distilled water were mixed and subjected to ultrasonic treatment for about 90 minutes at a frequency of 40 kHz and an output of 400 W. Conducted under conditions to prepare a Sb ₂ Te ₃ nanoplate solution to which SDS having a negative charge is bound.

12 ml of the PDDA-bonded graphene exfoliated product and 12 ml of the SDS-bonded Sb ₂ Te ₃ nanoplate solution were mixed, and a sonic tip (SONIC VX-750 ultrasonic processor with a flate head tip) was used to obtain about 540 W. Output, ultrasonic treatment was performed for about 20 minutes at a frequency of 20 kHz to prepare a self-assembled nanostructured graphene/Sb ₂ Te ₃ composite laminate.

Example 2: Graphene - Sb ₂ Te ₃ complex Laminated Produce

Mixing the graphene exfoliated product obtained according to Preparation Example 1, EG 4mg and SDBS 30ml, and using a sonic tip (SONIC VX-750 ultrasonic processor with a flate head tip) of about 540W at a frequency condition of 20 kHz The sonication was performed for about 90 minutes to prepare a positively charged PDDA-bonded graphene peel.

The Preparative Example 5 IBr doped Sb ₂ Te ₃ nano-sheets (nanosheet) 15mg and distilled water to the reaction 30ml IBr-doped Sb ₂ Te ₃ stripping water obtained according to was prepared.

12 ml of the PDDA-bonded graphene exfoliated material and 1 ml of the IBr-doped Sb ₂ Te ₃ exfoliated material are mixed, and a sonic tip (SONIC VX-750 ultrasonic processor with a flate head tip) is used to output about 540 W, Ultrasonic treatment was performed for about 20 minutes under a frequency condition of 20 kHz to prepare a self-assembled nanostructure, graphene/Sb ₂ Te ₃ composite laminate.

Comparative example One: Graphene / Sb ₂ Te ₃ Blended Produce

4 mg of EG prepared according to Preparation Example 1 and 30 ml of N-methylpyrrolidone (NMP) were mixed, and ultrasonic waves were applied thereto at a frequency of 40 kHz and an output condition of 400 W for 2 hours to obtain an EG-NMP mixture.

Separately, 15 mg of the Sb ₂ Te ₃ nanoplate prepared according to Preparation Example 6 and 30 ml of N-methylpyrrolidone were mixed, and ultrasonic waves were added thereto at a frequency of 40 kHz and an output condition of 400 W for 2 hours to obtain Sb ₂ A Te ₃ -NMP mixture was obtained.

12ml of the EG-NMP mixture and 12ml of the Sb ₂ Te ₃ -NMP mixture were mixed, and ultrasonic waves were added thereto for 30 minutes at a frequency of 40 kHz and an output condition of 400 W to prepare a graphene/Sb ₂ Te ₃ blend.

Evaluation example One: XRD Measure

In the following XRD analysis, 12KW XRD of BRUKER AXS was used, and the analysis conditions were carried out under measurement conditions of 4° per minute in the range of 5°-80°.

1) Sb ₂ Te ₃ prepared according to Preparation Example 6 Nano plate

Sb ₂ Te ₃ prepared according to Preparation Example 6 XRD analysis of the nanoplate was performed, and the results are shown in FIG. 5A.

Referring to FIG. 5A, it was confirmed that it has crystal planes of (015), (1010), (110), and (0018). Through this Sb ₂ Te ₃ It was found that the nanoplate is a thermoelectric semiconductor material having a hexagonal structure.

2) Samples 1 to 3

i) Sample 1

0.5 g of Sb ₂ Te ₃ (Alfa Asear) powder and IBr (Iodine bromide) according to Preparation Example 2

After 1g was mixed, it was put in a container, the container was blocked from the outside, and maintained at 127°C for 48 hours to react so that the sublimated IBr particles penetrated between the solid Sb ₂ Te ₃ thermoelectric inorganic particles. The resulting powder was taken out from the blocked container to obtain Sb ₂ Te ₃ (Sample 1) intercalated with IBr.

i) Sample 2

Except for using ICl (Iodine chloride) instead of IBr (Iodine bromide), it was carried out in the same manner as in Sample 1 to obtain ICl-intercalated Sb ₂ Te ₃ (Sample 2).

ii) Sample 3

Sb intercalated with IBr according to the same method as in Sample 1, except that the reaction temperature of 0.5 g of Sb ₂ Te ₃ (Alfa Asear) powder and 1 g of IBr (Iodine bromide) was changed from 127°C to 78°C. ₂ Te ₃ (Sample 3) was obtained.

XRD analysis of Samples 1 to 3 was performed, and the results are shown in FIG. 5B. In FIG. 5B, data for raw Sb ₂ Te ₃ (Alfa Asear) powder are also shown for comparison with Samples 1 to 3.

Referring to Figure 5b, it was confirmed that Samples 1 to 3 have crystal planes of (003) and (006) as in the raw Sb ₂ Te ₃ (Alfa Asear) powder, and as the type of the interlayer insert and the heat treatment temperature vary, (006 ), it was found that the peak related to the crystal plane shifted. Through this, it was found that the interlayer distance of Sb2Te3 increased.

Evaluation example 2: SEM analysis

In the following SEM analysis, (Jeol)'s (JSM-7600F) was used.

1) Sb ₂ Te ₃ nanoplate of Preparation Example 6

An electron scanning microscope analysis was performed on the Sb ₂ Te ₃ nanoplate obtained according to Preparation Example 6, and the results are shown in FIG. 6A. Referring to this, it was found that a hexagonal Sb ₂ Te ₃ nanoplate was formed.

2) Composite laminate of Example 2 (Fig. 6B)

Conducting an electron scanning microscope analysis of the composite laminate obtained according to Example 2

And the results are shown in FIG. 6B.

Referring to FIG. 6B, it was found that graphene and Sb ₂ Te ₃ were bonded to each other by different surface charges to form a composite laminate.

3) Composite laminate of Example 1

Conducting an electron scanning microscope analysis of the composite laminate obtained according to Example 1

And the results are shown in Fig. 6c.

Referring to FIG. 6C, the arrow indicates the exfoliated graphene of Preparation Example 1, and it was found that graphene and Sb ₂ Te ₃ were bonded to each other by different surface charges to form a composite laminate.

4) SEM analysis of the graphene/Sb ₂ Te ₃ blend of Comparative Example 1

SEM analysis was performed on the graphene/Sb ₂ Te ₃ blend obtained in Comparative Example 1, and the results are shown in FIG. 6D.

Referring to FIG. 6D, it could be confirmed that graphene and Sb ₂ Te ₃ were mixed randomly. From this, it can be seen that the graphene of Comparative Example 1 is not a self-assembled structure unlike the composite laminate of Example 1.

Evaluation example 3: HRTEM Wow SAED analysis

The following HRTEM/SAED analysis was performed using JEOL's HRTEM (800 kV).

HRTEM and SAED analysis were performed on the composite laminate obtained in Example 1, and the results are shown in FIG. 7.

Referring to FIG. 7, it was found that the composite laminate of Example 1 had a plane spacing of about 0.21 nm in HRTEM, which corresponds to the (110) plane of the Sb ₂ Te ₃ hexagonal system. And it was confirmed that the nanoplate was Sb ₂ Te ₃ single crystal through SAED.

Evaluation example 4: Raman spectrum analysis

Raman spectrum analysis was performed on the Sb ₂ Te ₃ nanoplate obtained in Preparation Example 6, and the results are shown in FIG. 8.

The Raman analysis was performed using Renishaw's RM-1000 Invia instrument (514 nm, Ar ⁺ ion laser).

With reference to Fig. 8 Sb ₂ Te ₃ nanoplate obtained in Production Example 6, a peak appears at 119, 251, 450cm ^-1, 119cm ^-1 intensity ratio of the peak / 251cm ^-1 peak is found to be about 2.8. From this, it was found that the Sb ₂ Te ₃ has a thin plate-like structure by observing the peak shown in the few nm thin film.

Evaluation example 5: Zeta potential Measure

The following zeta potential was measured using Malvern's Zetasizer Nano ZS.

PDDA-coupled graphene exfoliated product (graphene/PDDA) obtained according to Example 1, SDS-coupled Sb ₂ Te ₃ nanoplate (SDS/Sb ₂ Te ₃ ) and composite laminate (graphene/Sb ₂ The zeta potential of Te ₃ ) was measured and the results are shown in FIG. 9.

With reference to Figure 9, PDDA is combined with a positive surface charge graphene peeling water (SDS / Sb ₂ Te ₃₎ with which the SDS having a surface negative charge coupled Sb ₂ Te ₃ nano plate (SDS / Sb ₂ It was found that the composite laminate, which is a self-assembled structure obtained by bonding Te ₃ ), has a tendency to neutralize the surface charge by the electrostatic attraction of the graphene exfoliated product and the Sb ₂ Te ₃ nanoplate. .

1: graphene 2: thermoelectric weapon
100: power supply 111: graphite pressing die
112: lower punch electrode 113: composite powder
114: vacuum chamber

Claims (19)

Including graphene and thermoelectric inorganics,
A first ionic surfactant is bonded to the graphene, and a second ionic surfactant having a polarity different from that of the first ionic surfactant is bonded to the thermoelectric inorganic material or doped with an interhalogen compound,
A composite laminate that is a self-assembled structure in which ionic bonds are formed between the graphene and the thermoelectric inorganic material. The method of claim 1,
The composite laminate that the graphene has a laminated structure. The method of claim 1,
The composite laminate obtained by applying a microwave to the graphite intercalated compound (GIC) to obtain expanded graphite and dispersing it in a solvent. The method of claim 1,
The composite laminate in which the thermoelectric inorganic material has a thin film structure. The method of claim 1,
The thermoelectric inorganic material has a thin film structure, and the composite laminate has a thickness of 1 to 100 nm. The method of claim 1,
The thermoelectric inorganic material is Bi-Te based, Bi-Se based, Co-Sb based, Pb-Te based, Ge-Tb based, Si-Ge based, Bi-Sb-Te based, Sb-Te based and Sm-Co based A composite laminate that is one or more selected from compounds. The method of claim 1,
The thermoelectric inorganic material is Sb ₂ Te ₃ , Bi ₂ Te ₃ and Bi ₂ Se ₃ At least one composite laminate selected from among. The method of claim 1,
Intensity ratio of the peak (peak B) appearing in the ^{first (-} peak (peak A) and 251.3 ± 0.3 cm in the case shown in the composite laminate is thermally minerals of Sb ₂ Te ₃ 119.8 ± 0.8cm from the Raman spectra analyzed RAM ^-1 Peak A/Peak B) is a composite laminate of 2.5 to 2.9. A thermoelectric material comprising the composite laminate according to any one of claims 1 to 8. A thermoelectric device comprising the thermoelectric material according to claim 9. A first electrode;
A second electrode; And
A thermoelectric module interposed between the first electrode and the second electrode and including the thermoelectric element according to claim 10. Heat source; And
A thermoelectric element absorbing heat from the heat supply source;
A first electrode disposed to contact the thermoelectric element; And
A thermoelectric module disposed to face the first electrode and having a second electrode in contact with the thermoelectric element; and
The thermoelectric device comprising the thermoelectric material according to claim 9. Mixing graphene and a first ionic surfactant to obtain a graphene-containing mixture;
i) a thermoelectric inorganic material and having a polarity different from that of the first ionic surfactant
Mixing with a second ionic surfactant to obtain a mixture containing a thermoelectric inorganic substance or ii) obtaining a mixture containing a thermoelectric inorganic substance using a thermoelectric inorganic substance doped with an interhalogen compound; And
A method for producing a composite laminate to obtain the composite laminate of claim 1 including; mixing and reacting the graphene-containing mixture and the thermoelectric-inorganic-containing mixture. The method of claim 13,
The thermoelectric inorganic material,
Primary heat treatment of a thermoelectric inorganic material and an interhalogen compound in an airtight container; And
Performing a second heat treatment on the resultant of the first heat treatment in air;
The method of manufacturing a composite laminate manufactured by removing the interhalogen compound from the result of the secondary heat treatment and dispersing it in a solvent to perform ultrasonic treatment. The method of claim 13,
The first and second ionic surfactants are polydiallyldimethylammonium chloride (PDDA), sodium dodecyl sulfate (SDS), cetyltrimethylammonium bromide (CTAB), trimethylammonium bromide (TTAB), sodium cholate. (sodium cholate) (SC), sodium deoxycholate (DOC), and sodium taurodeoxycholate (sodium taurodeoxycholate) (TDOC) at least one selected from the method of manufacturing a composite laminate. The method of claim 13,
The thermoelectric inorganic material doped with the interhalogen compound is.
Primary heat treatment of a thermoelectric inorganic material and an interhalogen compound in an airtight container; And
Performing a second heat treatment on the resultant of the first heat treatment in air;
A method of manufacturing a composite laminate manufactured by dispersing the resultant secondary heat treatment in a solvent and performing ultrasonic treatment. The method of claim 13,
Obtaining the graphene-containing mixture, obtaining the thermoelectric inorganic substance-containing mixture; When performing one or more steps selected from the steps of mixing the graphene-containing mixture and the thermoelectric-inorganic-containing mixture, a method of manufacturing a composite laminate in which ultrasonic waves are applied. A composite laminate manufactured according to the manufacturing method of any one of claims 13 to 17. delete

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