KR20220091718A - Foldable Perovskite Solar Cell and method for preparing thereof - Google Patents

Abstract

The present invention relates to a foldable perovskite solar cell and a manufacturing method thereof and, more specifically, to a foldable perovskite solar cell and a manufacturing method thereof which use a transparent matrix made of an ultra-thin polymer and a carbon nanotube as a transparent conductor to increase a bending radius of the perovskite solar cell, thereby having an effect of increasing power conversion efficiency (PCE), mechanical elasticity and root-mean-square (RMS) roughness.

Description

Foldable Perovskite Solar Cell and method for preparing the same

The present invention relates to a foldable perovskite solar cell and a method for manufacturing the same, and more particularly, by using a transparent matrix composed of an ultra-thin polymer and carbon nanotubes as a transparent conductor, the bending radius of the perovskite solar cell foldable perovskite solar, which can improve It relates to a battery and a method for manufacturing the same.

Over the years, there has been an increasing interest in deformable electronics. Foldable electronics are emerging in both academia and industry, and foldable mobile phones have already entered the commercial market.

A solar cell is a device that directly converts light energy into electrical energy. At the beginning of commercialization, crystalline silicon solar cells were mostly used, but due to the high production cost of crystalline silicon, research on relatively inexpensive new solar cells such as inorganic thin-film solar cells, fuel-sensitized solar cells, and organic thin-film solar cells is being concentrated. Inorganic solar cells centered on silicon have high conversion efficiency, but have high cost in the manufacturing process and have limitations in weight and flexibility. For this reason, the demand for organic solar cells is expected mainly in the market where inorganic solar cells cannot be used.

Since organic solar cells use cheap organic materials, high productivity can be expected. In addition, since the thickness of the entire device is only a few hundred nm and it can be manufactured flexibly, there are few restrictions on weight, thickness, and shape, so it is expected to be applied as a power source for new uses such as ultra-small or mobile communication devices.

Recently, in the case of such a flexible organic solar cell, an attempt has been made to apply a conductive polymer material, for example, a PEDOT:PSS material, as an electrode layer. There was a problem that the efficiency of the organic solar cell was lowered due to high

Therefore, in order to supplement the above-mentioned problems, the present inventors recognized that it is urgent to develop a solar cell capable of improving the bending radius without lowering the efficiency of the solar cell, and completed the present invention.

Republic of Korea Patent Publication No. 10-2016-0097290 Republic of Korea Patent Publication No. 10-2019-0012798

An object of the present invention is to improve the bending radius of the perovskite solar cell by using a transparent matrix composed of an ultra-thin polymer and carbon nanotubes as a transparent conductor, and thereby power conversion efficiency (PCE) ), to provide a foldable perovskite solar cell that can have improved effects on mechanical elasticity and root-mean-square (RMS).

Another object of the present invention is to improve the bending radius of the perovskite solar cell by using a transparent matrix composed of an ultra-thin polymer and carbon nanotubes as a transparent conductor, and thereby power conversion efficiency, mechanical elasticity and average An object of the present invention is to provide a method for manufacturing a foldable perovskite solar cell capable of having an improved effect on square root roughness.

The technical problems to be achieved by the present invention are not limited to the technical problems mentioned above, and other technical problems not mentioned can be clearly understood by those of ordinary skill in the art from the description of the present invention.

In order to achieve the above object, the present invention provides a foldable perovskite solar cell and a manufacturing method thereof.

The present invention provides a first substrate; a transparent conductor positioned on the substrate; a hole transport layer positioned on the transparent conductor; perovskite positioned on the hole transport layer; a buffer layer located on the perovskite; and an upper electrode positioned on the buffer layer.

In the present invention, the transparent conductor may be a polymer film in which carbon nanotubes are embedded.

In the present invention, the polymer is poly (methyl methacrylate) (Poly methyl methacrylate, PMMA), polyimide (PI), polysulfone (polysulfone) and polyarylene ether nitrile (Polyarylene ether nitrile) group consisting of It may be at least one selected from

In the present invention, the carbon nanotubes may be at least one selected from the group consisting of multi-walled carbon nanotubes (MWNTs) and single-walled carbon nanotubes (SWNTs).

In the present invention, the thickness of the transparent conductor may be in the range of 5.0 to 9.0 μm.

In the present invention, the transparent conductor may have a root-mean-square (RMS) value of 0.2 to 0.5.

In addition, the present invention provides a method for manufacturing a foldable perovskite solar cell comprising the following steps.

(S1) preparing a transparent conductor including a polymer film in which the carbon nanotubes are embedded;

(S2) laminating the transparent conductor on the first substrate; and

(S3) sequentially laminating the hole transport layer, the perovskite layer, the electron transport layer and the upper electrode on the transparent conductor.

In addition, the present invention provides a method for manufacturing a foldable perovskite solar cell in which the step (S1) can be composed of the following steps.

(S1A) thermally depositing molybdenum trioxide (MoO ₃ ) on a second substrate;

(S1B) laminating carbon nanotubes on the thermally deposited molybdenum trioxide layer; and

(S1C) A step of applying a polymer precursor solution on the carbon nanotube, spin coating and curing to obtain a transparent conductor.

All matters mentioned in the foldable perovskite solar cell and its manufacturing method apply equally unless contradictory.

The foldable perovskite solar cell of the present invention and its manufacturing method can improve the bending radius of the perovskite solar cell by using a film composed of an ultra-thin polymer and carbon nanotubes as a transparent conductor, Due to this, it can have an improved effect on power conversion efficiency, mechanical elasticity and root mean square roughness.

Effects of the present invention are not limited to the effects mentioned above, and other effects not mentioned will be clearly understood by those skilled in the art from the description of the claims.

1 is a cross-sectional view schematically showing the structure of a foldable perovskite solar cell according to an embodiment of the present invention.
2 is a schematic diagram illustrating a method of manufacturing a transparent conductor composed of a polymer and carbon nanotubes according to an embodiment of the present invention.
3 is an atomic force microscope (AFM) image confirming the root mean square roughness of a transparent conductor according to an embodiment and a comparative example of the present invention.
4 is a graph showing the XPS spectrum of a transparent conductor according to an embodiment and a comparative example of the present invention.
5 is a graph showing series resistance and recombination resistance of transparent conductors according to an embodiment and a comparative example of the present invention.
6 is a graph showing power conversion efficiency according to a bending cycle of a solar cell made of a transparent conductor according to an embodiment and a comparative example of the present invention.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

The terms used in this specification have been selected as currently widely used general terms as possible while considering the functions in the present invention, but these may vary depending on the intention or precedent of a person skilled in the art, the emergence of new technology, and the like. In addition, in a specific case, there is a term arbitrarily selected by the applicant, and in this case, the meaning will be described in detail in the description of the corresponding invention. Therefore, the term used in the present invention should be defined based on the meaning of the term and the overall content of the present invention, rather than the name of a simple term.

Unless defined otherwise, all terms used herein, including technical and scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Terms such as those defined in a commonly used dictionary should be interpreted as having a meaning consistent with the meaning in the context of the related art, and should not be interpreted in an ideal or excessively formal meaning unless explicitly defined in the present application. does not

foldable perovskite solar cell

The present invention relates to a foldable perovskite solar cell using a transparent matrix composed of a polymer and carbon nanotubes as a transparent conductor.

Referring to FIG. 1 , the foldable perovskite solar cell 100 of the present invention includes a first substrate 10; a transparent conductor 20 positioned on the first substrate 10; a hole transport layer 30 positioned on the transparent conductor 20; a perovskite layer 40 positioned on the hole transport layer 30; an electron transport layer 50 positioned on the perovskite layer 40; and an upper electrode 60 positioned on the electron transport layer 50 .

The first substrate 10 is a configuration for supporting the configuration of the foldable perovskite solar cell 100, fluorine tin oxide (FTO), indium tin oxide (ITO), aluminum zinc oxide (AZO) , zinc tin oxide (ZTO), polydimethylsiloxane (PDMS) substrate and may be at least one selected from the group consisting of a quartz glass substrate (glass), preferably fluorine tin oxide (FTO), indium tin oxide (ITO) , may be at least one selected from the group consisting of a polydimethylsiloxane (PDMS) substrate and a quartz glass substrate, and most preferably a quartz glass substrate.

The transparent conductor 20 is laminated on the first substrate 10 and may be composed of a polymer and a carbon nanotube, preferably a polymer-carbon nanotube hybrid material.

The transparent conductor may be in the form of a film.

The polymer is at least one selected from the group consisting of poly methyl methacrylate (PMMA), polyimide (PI), polysulfone, and polyarylene ether nitrile. It may be one or more selected from the group consisting of poly(methyl methacrylate), polyimide and polyurethane, and most preferably polyimide.

The carbon nanotube may be at least one selected from the group consisting of multi-walled carbon nanotubes (MWNT) and single-walled carbon nanotubes (SWNT), preferably single-walled carbon nanotubes. It may be a tube.

The transparent conductor 20 may be formed in a thickness range of 5.0 to 9.0 μm, preferably in a thickness range of 5.5 to 8.5 μm, and most preferably in a thickness range of 6.0 to 8.0 μm. When the thickness of the transparent conductor 20 exceeds 9.0 μm or is lower than 5.0 μm, the foldable perovskite solar cell 100 according to the present invention cannot be folded and there is a risk that optical conductivity may be lowered.

The polymer of the transparent conductor 20 may permeate into the network of carbon nanotubes to exhibit a flat and smooth surface. More specifically, the root mean square roughness value of the transparent conductor 20 may be in the range of 0.2 to 0.5, and preferably, the root mean square roughness value of the transparent conductor 20 may be in the range of 0.3 to 0.5. When the root mean square roughness value of the transparent conductor 20 exceeds 0.5, the solar cell may exhibit low power conversion efficiency.

The transparent conductor 20 may have a light transmittance of 66% to 94% in a wavelength range of 450 nm to 800 nm, preferably 68% to 92% in a wavelength range of 450 nm to 800 nm and most preferably, the light transmittance may be 70% to 90% in the wavelength range of 450 nm to 800 nm.

The hole transport layer 30 may be a layer that is laminated on the transparent conductor 20 and serves to transfer holes in the foldable perovskite solar cell 100 according to the present invention.

The hole transport layer 30 is 1 selected from the group consisting of PEDOT:PSS, poly(3-hexylthiophene) (Poly(3-hexylthiophene), P3HT) and poly(triarylamine) (Poly(triarylamine), PTAA) It may be more than one species, and may preferably be poly(triarylamine).

The hole transport layer 30 may be stacked to a thickness of 5 to 50 nm, preferably from 10 to 35 nm, and most preferably from 15 to 30 nm.

The perovskite layer 40 is stacked on the hole transport layer 30 and may be composed of MA _a FA _b PbI _c X _d . More specifically, in the MA _a FA _b PbI _c X _d MA may be a methylammonium cation, FA in MA _a FA _b PbI _c X _d may be a formamidinium cation, and X in MA _a FA _b PbI _c X _d may be Br or I. In addition, each of a and b may be 0.1 to 1.5, preferably 0.2 to 1.0. The c may be 1.0 to 5.0, preferably 1.5 to 4.0. The d may be 0.01 to 0.2, preferably 0.05 to 0.15.

The perovskite layer 40 may be stacked to a thickness of 350 to 550 nm, preferably from 400 to 500 nm, and most preferably from 425 to 475 nm.

The electron transport layer 50 is stacked on the perovskite layer 40, and is composed of PCBM (fullerene derivative), C ₆₀ (fullerene), and lithium fluoride (LiF) and titanium dioxide (TiO ₂ ). It may be at least one selected from, and preferably C ₆₀ (fullerene).

The electron transport layer 50 may be laminated to a thickness of 5 to 30 nm, preferably, may be laminated to a thickness of 10 to 25 nm.

Meanwhile, when the electron transport layer 50 is stacked, an additive may be introduced into the electron transport layer 50 to improve the performance of the perovskite layer 40 . The additive may be at least one selected from the group consisting of Bathocuproine (BCP) and SNS (tin sulfide), preferably basocubroin. The thickness of the additive may be 2 to 14 nm, preferably 4 to 10 nm, and most preferably 5 to 8 nm.

The upper electrode 60 is stacked on the electron transport layer 50 and may be made of metal. The metal may be at least one selected from the group consisting of Au, Pt, Ti, Ag, Ni, Zr, Ta, Zn, Nb, Cr, Co, Mn, Fe, Al, Mg, Si, W and Cu, preferably Preferably, the metal may be at least one selected from the group consisting of Au, Pt, Ti, Ag, and Cu.

The upper electrode 60 may be stacked to a thickness of 30 to 70 nm, preferably from 35 to 65 nm, and most preferably from 45 to 55 nm.

Manufacturing method of foldable perovskite solar cell

The present invention relates to a method for manufacturing a foldable perovskite solar cell comprising the following steps.

(S1) preparing a transparent conductor including a polymer film in which the carbon nanotubes are embedded;

(S2) laminating the transparent conductor on the first substrate; and

(S3) sequentially laminating the hole transport layer, the perovskite layer, the electron transport layer and the upper electrode on the transparent conductor.

The step (S1) is a step of manufacturing the transparent conductor, and may consist of the following steps:

(S1A) thermally depositing molybdenum trioxide (MoO ₃ ) on a second substrate;

(S1B) laminating carbon nanotubes on the thermally deposited molybdenum trioxide layer; and

(S1C) A step of applying a polymer precursor solution on the carbon nanotube, spin coating and curing to obtain a transparent conductor.

The step (S1A) is a step of depositing molybdenum trioxide on a substrate, and the molybdenum trioxide may be deposited on the second substrate through a thermal vacuum evaporation process. The second substrate may be at least one selected from the group consisting of soda lime and a quartz glass substrate, and most preferably a quartz glass substrate.

The molybdenum trioxide may be deposited to a thickness of 1 to 16 nm, preferably may be deposited to a thickness of 1 to 12 nm, and most preferably may be deposited to a thickness of 1 to 8 nm, and the molybdenum trioxide may be deposited to a thickness of 1 to 8 nm. When the thickness of the transparent conductor exceeds 16 nm, the sheet resistance of the transparent conductor may decrease, and the current density may decrease.

Step (S1B) is a step of stacking carbon nanotubes on the thermally deposited molybdenum trioxide layer.

When the carbon nanotubes are stacked on the molybdenum trioxide, the carbon nanotubes may be mechanically deposited or chemically deposited, more preferably mechanically.

The carbon nanotubes may be stacked on the molybdenum trioxide at a temperature of 60 to 80° C., preferably, on the molybdenum trioxide at a temperature of 65 to 75° C.

When the carbon nanotube and the molybdenum trioxide are in contact, charge transfer occurs at the contact surface of the carbon nanotube and the molybdenum trioxide, and the molybdenum trioxide may be partially reduced due to the charge transfer.

The molybdenum trioxide may be used as a dopant in a doping process for improving the electrical conductivity of the carbon nanotube and improving the performance of the optoelectronic device. That is, a p-doping process using molybdenum trioxide as a dopant may be performed to improve the electrical conductivity of the carbon nanotube and improve the performance of the optoelectronic device.

The molybdenum trioxide used as the dopant may induce doping under high temperature conditions, for example, at a temperature of 300°C to 500°C, preferably at a temperature of 300°C to 450°C.

Molybdenum trioxide used as the dopant may induce doping under anaerobic conditions.

The step (S1C) is a step of obtaining a transparent conductor by applying the polymer precursor solution on the carbon nanotubes, spin-coating and curing the solution.

The polymer is at least one selected from the group consisting of poly methyl methacrylate (PMMA), polyimide (PI), polysulfone, and polyarylene ether nitrile. It may be one or more selected from the group consisting of poly(methyl methacrylate), polyimide and polyurethane, and most preferably polyimide.

The spin coating step may be performed for 30 seconds to 90 seconds, preferably for 40 seconds to 80 seconds, and most preferably for 50 seconds to 70 seconds.

The spin coating step may be performed at 2000 rpm to 3000 rpm, preferably at 2250 to 2750 rpm, and most preferably at 2400 to 2600 rpm.

In the spin coating step, the polymer precursor solution may be absorbed into the carbon nanotubes to block oxygen to form anaerobic conditions.

In addition, after the spin coating step, the first annealing may be performed at a temperature of 150 ° C. to 250 ° C., and the second annealing may be performed at a temperature of 250 ° C. to 350 ° C. In this case, the curing step may be performed together. have.

The curing step may be performed under an aerobic or anaerobic environment, and preferably may be performed under an anaerobic environment.

After the step (S1C), the finally obtained transparent conductor may be separated from the second substrate.

The step (S2) may be a step of laminating the transparent conductor finally obtained through the steps (S1A) to (S1C) on the first substrate.

The first substrate is as described for the first substrate 10 in the foldable perovskite solar cell section.

In the step (S3), the hole transport layer 30, the perovskite 40, the electron transport layer 50 and the upper electrode 60 are formed on the transparent conductor 20 stacked on the first substrate 10. It may include the step of sequentially stacking.

The hole transport layer 30 may be laminated by performing an annealing process after spin coating a solution in which the hole transport layer material is dissolved in a solvent.

The hole transport layer material is at least one selected from the group consisting of PEDOT:PSS, poly(3-hexylthiophene) (Poly(3-hexylthiophene), P3HT) and poly(triarylamine) (Poly(triarylamine), PTAA). and preferably poly(triarylamine).

The solvent may be at least one selected from the group consisting of chlorobenzene, chloroform, toluene and dichlorobenzene, preferably chlorobenzene.

The spin coating step may be performed for 10 seconds to 50 seconds, preferably for 20 seconds to 40 seconds, and most preferably for 25 seconds to 35 seconds.

The spin coating step may be performed at 4000 rpm to 8000 rpm, preferably at 5000 to 7000 rpm, and most preferably at 5500 to 6500 rpm.

The annealing process after the spin coating step may be performed for 5 minutes to 20 minutes, preferably for 9 minutes to 12 minutes, and may be performed at a temperature of 50° C. to 150° C., preferably 75 It can be carried out at a temperature of ℃ to 125 ℃.

An interfacial compatibilizer (PFN-X) may be coated on the hole transport layer material. More specifically, X may be Cl, Br or I. The concentration of the PFN-X may be 0.1 mg/mL to 1.0 mg/mL, preferably 0.2 mg/mL to 0.7 mg/mL, and most preferably 0.3 mg/mL to 0.5 mg/mL. can

After the step of laminating the hole transport layer 30 , the perovskite layer 40 having a composition of MA _a FA _b PbI _c X _d (description of each symbol is as described above) may be laminated. The perovskite layer 40 may be prepared by dissolving the materials PbX, MAX, FAX, and MAX (each symbol is the same as described above), which are raw materials of the perovskite, in a polar solvent.

The polar solvent may be at least one selected from the group consisting of N-dimethylformamide (DMF), γ-butyrolactone, methyl-2-pyrrolidinone (NMP) and dimethyl sulfoxide (DMSO), preferably It may be at least one selected from the group consisting of methyl-2-pyrrolidinone (NMP) and dimethyl sulfoxide (DMSO).

Thereafter, spin coating the prepared solution and annealing may be followed.

The spin coating step may be performed at 3000 to 5000 rpm, preferably at 3500 to 4500 rpm.

The spin coating step may be performed for 10 to 30 seconds, preferably 15 to 25 seconds.

The annealing step may be performed at a temperature of 50 °C to 180 °C, preferably at a temperature of 70 °C to 150 °C.

The annealing step may be performed for 10 to 30 minutes, preferably 15 to 25 minutes.

After the perovskite layer 40 lamination step, the electron transport layer 50 may be laminated. At the same time, additives may be introduced to improve the performance of the perovskite layer 40 .

The stacking of the electron transport layer 50 may be performed by one type selected from the group consisting of a vacuum thermal evaporation method and an electron beam evaporation method.

The electron transport layer 50 may be stacked at a rate of 0.2 to 1.0 Å/s, preferably at a rate of 0.4 to 0.6 Å/s.

Finally, the upper electrode 60 may be stacked. The upper electrode 60 may be a metal, and the metal is Au, Pt, Ti, Ag, Ni, Zr, Ta, Zn, Nb, Cr, Co, Mn, Fe, Al, Mg, Si, W and Cu. It may be at least one selected from the group consisting of, preferably, the metal may be at least one selected from the group consisting of Au, Pt, Ti, Ag, and Cu.

The upper electrode 60 may have an area of 0.60 to 1.20 cm ² , preferably 0.80 to 1.00 cm ² .

Example

Hereinafter, examples of the present invention will be described in detail, but it is obvious that the present invention is not limited by the following examples.

Advantages and features of the present invention, and a method of achieving them, will become apparent with reference to the embodiments described below in detail. However, the present invention is not limited to the embodiments disclosed below, but may be implemented in various different forms, and only the embodiments allow the disclosure of the present invention to be complete, and common knowledge in the technical field to which the present invention pertains It is provided to fully inform those who have the scope of the invention, and the present invention is only defined by the scope of the claims.

Example 1: Preparation of polymer-carbon nanotube transparent conductor

As shown in FIG. 2 , molybdenum trioxide was deposited on a quartz substrate through a thermal vacuum evaporation process. Then, a carbon nanotube film was mechanically deposited on a quartz glass substrate. A viscous, pale yellow polyimide precursor solution was spin-coated on the single-walled carbon nanotubes deposited on the quartz substrate at 2500 rpm for 60 seconds to form polyimide-single-walled carbon nanotubes. Thereafter, the polyimide-single-walled carbon nanotubes were dried at 90° C. for 5 minutes. The substrate was completely cured by performing the first annealing at 200° C. for 20 minutes and the second annealing at 300° C. for 20 minutes. The polyimide-single-walled carbon nanotubes were cooled to room temperature, immersed in demineralized water, and separated from the substrate to complete a transparent conductor.

Comparative Example 1

According to a method known in the art, a film in which indium tin oxide (ITO) was laminated on a polyethylene naphthalate (PEN) substrate was prepared.

Comparative Example 2

According to a method known in the art, a film in which single-walled carbon nanotubes were laminated on a polyethylene naphthalate (PEN) substrate was prepared.

Comparative Example 3

A film was prepared in the same manner as in Example 1, except that a polyethylene naphthalate (PEN) substrate was used instead of the quartz substrate.

Comparative Example 4

A film was prepared in the same manner as in Example 1, except for depositing molybdenum trioxide on the quartz substrate.

Experimental Example 1: AFM observation

3 is an atomic force microscope (AFM) image of the surface topography of the films prepared in Example 1, Comparative Example 2 and Comparative Example 4, and the values specified at the bottom of the image are root-mean-square (rms). ) value, and the smaller the root mean square roughness value, the smoother the film surface. 3, the films of Example 1 and Comparative Example 4 had a small root mean square roughness value because the polymer polyimide permeated into the carbon nanotube network, whereas the film of Comparative Example 2 had a root mean square roughness value. Big.

Experimental Example 2: XPS observation

4 is a graph showing XPS spectra of Example 1 and Comparative Example 3. FIG. From Figure 4a, it can be seen that the Mo 3d spectrum of Example 1 has an additional peak at 229.8 eV compared to Comparative Example 3, and from the O 1s peak of Figure 4b, it can be seen that the binding energy of Example 1 is higher . This may mean that strong doping of molybdenum trioxide was induced during curing of the polyimide-single-walled carbon nanotubes in Example 1.

Experimental Example 3: p-doping effect of molybdenum trioxide

From Table 1 and FIG. 5, it can be seen that the film of Example 1 is superior to the film of Comparative Example 4 in open-circuit voltage, short-circuit current, charge rate, power conversion efficiency, series resistance and recombination resistance, which is 1, it may mean that the p-doping effect was induced due to molybdenum trioxide.

Perovskite solar cell fabrication

The polyimide-single-walled carbon nanotube film prepared in Example 1 was laminated on a polydimethylsiloxane (PDMS) substrate. Thereafter, 10 mg of PTAA (Sigma Aldrich) was dissolved in 1 mL of chlorobenzene to prepare a PTAA solution. After spin coating the solution at 6000 rpm for 30 seconds, an annealing process was performed at 100° C. for 10 minutes. PFN-Br, an interfacial compatibilizer, was coated on PTAA. The concentration of the PFN-Br was 0.4 mg/mL. Then, in 0.55 mL of N-dimethylformamide (DMF) (Sigma Aldrich), 461 mg of PbI ₂ (Sigma Aldrich), 79.5 mg of methylammonium iodide (MAI) (Greatcell Solar), 68.8 mg of forma A perovskite solution was prepared by dissolving midinium iodide (FAI) (Greatcell Solar), and 11.2 mg of MABr (Greatcell Solar). The solution was spin coated at 4000 rpm for 20 seconds. C ₆₀ (20 nm thick) was deposited on the perovskite layer at a rate of 0.5 Å/s, and BCP (6 nm thick) was laminated at a rate of 0.3 Å/s. At this time, the lamination step was performed by a vacuum thermal evaporation method. Finally, Cu (50 nm thick) was laminated on the BCP film having an area of 0.90 cm ² . All procedures were carried out at a temperature of 25° C. and a relative humidity of 10%.

Experimental Example 4: Bending Test of Perovskite Solar Cells

A bending test was performed using a cyclic bending flexibility tester (ScienceTown) at a bending frequency of 1 Hz. As can be seen in FIG. 6 , in the case of the solar cell prepared from the film of Comparative Example 1, the power conversion efficiency continued to decrease in the bending radius test of 4 mm, and was significantly reduced after 1,000 bending cycles. On the other hand, in the solar cell prepared from the film of Example 1, in the bending radius test of 1 mm, the power conversion efficiency was maintained constant even after 1,000 bending cycles.

From the above description, those skilled in the art to which the present invention pertains will understand that the present invention may be implemented in other specific forms without changing the technical spirit or essential characteristics thereof. In this regard, it should be understood that the embodiments described above are illustrative in all respects and not restrictive.

Claims (8)

a first substrate;
a transparent conductor positioned on the first substrate;
a hole transport layer positioned on the transparent conductor;
a perovskite layer positioned on the hole transport layer;
an electron transport layer positioned on the perovskite layer; and
A foldable perovskite solar cell comprising a; an upper electrode positioned on the electron transport layer. The foldable perovskite solar cell according to claim 1, wherein the transparent conductor is a polymer film in which carbon nanotubes are embedded. According to claim 2, wherein the polymer is made of poly (methyl methacrylate) (Poly methyl methacrylate, PMMA), polyimide (PI), polysulfone (polysulfone) and polyarylene ether nitrile (Polyarylene ether nitrile) One or more foldable perovskite solar cells selected from the group. According to claim 2, wherein the carbon nanotube is multi-walled carbon nanotubes (Multi Walled Carbon Nanotubes, MWNT) and single-walled carbon nanotubes (Single Walled Carbon Nanotubes, SWNT) at least one selected from the group consisting of foldable peroves Skye Solar Cell. The foldable perovskite solar cell according to claim 2, wherein the thickness of the transparent conductor is in the range of 5.0 to 9.0 μm. The foldable perovskite solar cell according to claim 2, wherein a root-mean-square (RMS) value of the transparent conductor is in the range of 0.2 to 0.5. (S1) preparing a transparent conductor including a polymer film in which the carbon nanotubes are embedded;
(S2) laminating the transparent conductor on the first substrate; and
(S3) sequentially stacking the hole transport layer, the perovskite layer, the electron transport layer and the upper electrode on the transparent conductor; a method of manufacturing a foldable perovskite solar cell comprising a. The method of claim 7, wherein the step (S1)
(S1A) thermally depositing molybdenum trioxide (MoO ₃ ) on a second substrate;
(S1B) laminating carbon nanotubes on the thermally deposited molybdenum trioxide layer; and
(S1C) A method of manufacturing a foldable perovskite solar cell comprising; applying a polymer precursor solution on the carbon nanotube, spin-coating, and curing to obtain a transparent conductor.

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