Transport layer, preparation method and flexible perovskite battery

Abstract

The invention provides a transport layer, a preparation method and a flexible perovskite cell, and the method comprises the steps: adding a nanocrystalline charge transport material into a first solvent, and obtaining a first solution with the concentration of 1-30 wt%; wherein the nanocrystalline charge transport material comprises nickel oxide and tin oxide; polyacrylonitrile is added into a second solvent, and a second solution with the concentration being 0.1 wt%-10 wt% is obtained; mixing the first solution and the second solution in equal volume to obtain a transmission layer solution; and preparing the transport layer solution into a transport layer. The transmission layer is good in interface compatibility and excellent in mechanical property.

Description

Technical Field

[0001] This application relates to the technical field of flexible perovskite solar cell preparation, and particularly relates to a transport layer, a preparation method, and a flexible perovskite solar cell. Background Art

[0002] Since flexible perovskite solar cells need to be able to adapt to deformations such as bending and folding, the transport layer material must have good flexibility. This flexibility ensures that when the solar cell is bent or folded, the transport layer will not break or be damaged, thus maintaining the normal operation of the solar cell. At the same time, the interfacial compatibility between the material of the transport layer and the perovskite layer as well as other solar cell components in the flexible perovskite solar cell can ensure the effective transport of charges between the interfaces, reduce charge losses, and thus improve the efficiency of the solar cell. Therefore, the transport layer still needs to have a certain mechanical strength while ensuring flexibility to maintain the structural integrity during the preparation, transportation, and use of the flexible perovskite solar cell. Currently, the comprehensive performance of the transport layer is poor. Summary of the Invention

[0003] This application aims to at least partly solve one of the technical problems in the related art. This application proposes a transport layer, a preparation method, and a flexible perovskite solar cell. By adding a nanocrystal charge transport material and polyacrylonitrile with a scientific ratio to the transport layer solution, a transport layer with good interfacial compatibility and excellent mechanical properties can be achieved.

[0004] To achieve the above object, according to the first aspect of this application, a preparation method of a transport layer applicable to a flexible perovskite solar cell is proposed.

[0005] Add the nanocrystal charge transport material to a first solvent to obtain a first solution with a concentration of 1 wt% - 30 wt%; wherein the nanocrystal charge transport material includes nickel oxide and tin oxide.

[0006] Add polyacrylonitrile to a second solvent to obtain a second solution with a concentration of 0.1 wt% - 10 wt%.

[0007] Mix the first solution and the second solution in equal volume to obtain a transport layer solution.

[0008] Prepare the transport layer solution into a transport layer.

[0009] In some embodiments, the first solvent is an aqueous solution.

[0010] And / or, the aqueous solution includes water and / or ethanol.

[0011] In some embodiments, the second solvent is an organic solution.

[0012] And / or, the organic solution includes N,N-dimethylformamide or a sulfur-containing organic compound.

[0013] And / or, the sulfur-containing organic compound is dimethyl sulfoxide.

[0014] In some embodiments, the transport layer solution is formed into a coating by spin coating or blade coating, and dried and shaped to form the transport layer;

[0015] The drying parameters of the coating are 80-150 °C and it is dried for 10-15 min.

[0016] In some embodiments, the transport layer solution adopts the blade coating method and is blade-coated on the surface of the substrate at 5 mm / s - 10 mm / s to form the coating

[0017] In some embodiments, the thickness of the transport layer is 10-25 nm.

[0018] According to a second aspect of the present application, a transport layer suitable for a flexible perovskite battery is provided, which is prepared by using the method described in any of the above embodiments.

[0019] According to a third aspect of the present application, a flexible perovskite battery is provided, including the transport layer described in any of the above embodiments.

[0020] In some embodiments, the flexible perovskite battery further includes a substrate, a semiconductor material layer, a perovskite layer, an electron transport layer, and a metal layer.

[0021] In some embodiments, the transport layer is located between the semiconductor material layer and the perovskite layer.

[0022] The additional aspects and advantages of the present application will be partially given in the following description, partially become apparent from the following description, or be understood through the practice of the present application. Description of the Drawings

[0023] The above and / or additional aspects and advantages of the present application will become apparent and easy to understand from the following description of the embodiments in conjunction with the drawings, where:

[0024] Figure 1 is a flowchart of the preparation method of the transport layer in an embodiment of the present application. Detailed Embodiments

[0025] The embodiments of the present application will be described in detail below. The examples of the embodiments are shown in the drawings, where the same or similar reference numerals denote the same or similar elements or elements with the same or similar functions from beginning to end. The embodiments described below by referring to the drawings are exemplary and are only used to explain the present application and should not be construed as a limitation of the present application. On the contrary, the embodiments of the present application include all changes, modifications, and equivalents falling within the spirit and scope of the appended claims.

[0026] This application is an improvement based on the following related technologies: Since flexible perovskite batteries need to be able to adapt to deformations such as bending and folding, the transport layer material must have good flexibility. This flexibility ensures that when the battery is bent or folded, the transport layer will not break or be damaged, thus maintaining the normal operation of the battery. At the same time, the interfacial compatibility between the material of the transport layer in the flexible perovskite battery and the perovskite layer as well as other battery components can ensure the effective transport of charges between the interfaces, reduce charge loss, and thus improve the efficiency of the battery. Therefore, the transport layer still needs to have a certain mechanical strength while ensuring flexibility to maintain the structural integrity during the preparation, transportation, and use of the flexible perovskite battery. Currently, the comprehensive performance of the transport layer is poor.

[0027] This application aims to solve at least one of the technical problems in the related technologies to some extent. To achieve the above object, according to the first aspect of this application, a method for preparing a transport layer is proposed, as Figure 1 shown:

[0028] S1: Add the nanocrystal charge transport material to the first solvent to obtain a first solution with a concentration of 1 wt% - 30 wt%; wherein the nanocrystal charge transport material includes nickel oxide and tin oxide;

[0029] S2: Add polyacrylonitrile to the second solvent to obtain a second solution with a concentration of 0.1 wt% - 10 wt%;

[0030] S3: Mix the first solution and the second solution in equal volume to obtain a transport layer solution;

[0031] S4: Prepare the transport layer solution into a transport layer.

[0032] Among them, in S1, the nanocrystal charge transport material is added to the first solvent, where the first solvent is an aqueous solution, which can be solutions such as water and ethanol. The nanocrystal charge transport material includes nickel oxide and tin oxide; that is, the nanocrystal charge transport material is added to the first solvent and ultrasonically dispersed for 10 min - 20 min to obtain the first solution, and the concentration of the first solution is 1 wt% - 30 wt%. For example, the concentration of the first solution is 1 wt%, 3 wt%, 5 wt%, 8 wt%, 10 wt%, 17 wt%, 21 wt%, 30 wt%, etc. If the concentration of the first solution is too large, it will cause the formed transport layer film to be uneven and the transport effect to deteriorate; when the concentration of the first solution is too small, such as less than 1 wt%, it will cause the finally formed transport layer to be uneven and discontinuous and not formed.

[0033] It should be explained that when the nanocrystal charge transport material is nickel oxide, the transport layer prepared in this embodiment is an electron transport layer; when the nanocrystal charge transport material is tin oxide, the transport layer prepared in this embodiment is a hole transport layer.

[0034] Among them, in S2, polyacrylonitrile is added to a second solvent, where the second solvent is an organic solution; the organic solution includes N,N-dimethylformamide or a sulfur-containing organic compound; an example of the sulfur-containing organic compound can be dimethyl sulfoxide; acrylonitrile is added to the second solvent and stirred at room temperature for 10 minutes to form a second solution. The concentration of the second solution is 0.1 wt% - 10 wt%. Exemplarily, the concentration of the second solution is 0.1 wt%, 0.3 wt%, 0.5 wt%, 1 wt%, 2 wt%, 3 wt%, 4 wt%, 6 wt%, 8 wt%, etc. If the concentration of the second solution is too large, it will cause the formed transport layer film to be uneven and the transport effect to deteriorate; when the concentration of the second solution is too small, such as less than 0.1 wt%, it will cause the finally formed transport layer to be uneven and discontinuous and not formed, etc.

[0035] Among them, in S3, the first solution and the second solution are mixed in equal volume to obtain a transport layer solution, and in S4, the transport layer solution is formed into a coating by spin coating or blade coating. For example, when the transport layer solution uses blade coating, it is blade-coated on the substrate surface at 5 mm / s - 10 mm / s to form a coating. The coating is heated at 80 - 150 °C and dried for 10 - 15 min to be shaped into a transport layer; the thickness of the transport layer is 10 - 25 nm.

[0036] According to the second aspect of the present application, a transport layer suitable for a flexible perovskite battery is provided, which is prepared by using the method in any of the above embodiments.

[0037] According to the third aspect of the present application, a flexible perovskite battery is provided, including the transport layer in any of the above embodiments.

[0038] In some embodiments, the flexible perovskite battery further includes a substrate, a semiconductor material layer, a perovskite layer, a second charge transport layer, and a metal layer.

[0039] The flexible perovskite battery includes a substrate, a semiconductor material layer, a transport layer, a perovskite layer, a second charge transport layer, and a metal layer; when the transport layer prepared in the present application is an electron transport layer, the second charge transport layer corresponds to a hole transport layer; when the transport layer prepared in the present application is a hole transport layer, the second charge transport layer corresponds to an electron transport layer.

[0040] To facilitate further understanding of the present application, the solutions of the present application will be further described below in conjunction with embodiments. Those skilled in the art will understand that only some embodiments are described in the present application, and any other suitable specific embodiments are within the scope of the present application.

[0041] Example 1

[0042] This embodiment proposes a transport layer, and its preparation method is as follows: Clean a 3*3 cm ITO substrate (the thickness of polyethylene naphthalate (PEN) is 0.5 mm, and the thickness of the ITO film layer is 100 nm). Add nickel oxide nanoparticles to water and

[0043] ultrasonically disperse for 10 min to obtain a first solution with a concentration of 10 wt%; dissolve polyacrylonitrile in a DMF solution and stir at room temperature for 10 minutes to form a second solution with a concentration of 6 wt%; mix the first solution and the second solution in equal volumes to obtain a transport layer solution, and use a doctor blade method (5 mm / s) to scrape the transport layer solution on the surface of the above ITO substrate; and dry it on a hot stage at 100 °C for 10 min to obtain a transport layer with a thickness of 20 nm. The contact angle of the transport layer in this embodiment is tested, and the contact angle of the transport layer is 11°. The smaller the wetting angle, the better the wettability. The transport layer in this application has good interfacial contact.

[0044] Prepare a perovskite layer precursor solution, where the solvent in the perovskite layer precursor solution is DMF, and CsB, PbI2, FAI, and NH4Cl are added. In the perovskite layer precursor solution, CsBr is 0.15 mol / L, PbI2 is 1 mol / L, FAI is 0.85 mol / L, and NH4Cl is 0.3 mol / L. Take the prepared perovskite precursor solution and spin-coat it evenly on the transport layer prepared in this embodiment. When spin-coating, the parameters of the spin coater are set as an acceleration of 500 rpm / s, a rotation speed of 3500 rpm, and a time of 40 s. Then transfer the spin-coated wet film to a vacuum device, quickly evacuate to below 20 Pa and maintain for 20 s, then take out the film, place the film on a hot stage at 160 °C for annealing for 2 min, and then transfer the film to a hot stage at 130 °C for annealing for 15 min to obtain a perovskite film with a thickness of 380 nm. Evaporate a 40-nm C60 electron transport layer on the surface of the perovskite film prepared in this embodiment.

[0045] Transfer the obtained product to a thermal evaporation device. Under the condition that the vacuum degree reaches 1×10 -5 Pa, evaporate a gold electrode (Au) on the surface of the C60 electron transport layer. The thickness of the gold electrode is 100 nm to obtain a perovskite solar cell.

[0046] Example 2

[0047] This embodiment presents a transport layer, and its preparation method is as follows: Clean a 3*3 cm ITO substrate (with a polyethylene naphthalate (PEN) thickness of 0.5 mm and an ITO film layer thickness of 100 nm). Add nickel oxide nanoparticles to water and ultrasonically disperse for 10 min to obtain a first solution with a concentration of 20 wt%. Dissolve polyacrylonitrile in a DMF solution and stir at room temperature for 10 minutes to form a second solution with a concentration of 3 wt%. Mix the first solution and the second solution in equal volumes to obtain a transport layer solution, and use a doctor blade method (5 mm / s) to scrape the transport layer solution on the surface of the above ITO substrate; then dry it on a hot stage at 100 °C for 10 min to obtain a transport layer with a thickness of 20 nm. Among them, the contact angle of the transport layer in this embodiment is tested, and the contact angle of the transport layer is 10.5°.

[0048] Prepare a perovskite layer precursor solution, where the solvent in the perovskite layer precursor solution is DMF, and CsBr, PbI2, FAI, and NH4Cl are added. In the perovskite layer precursor solution, CsBr is 0.15 mol / L, PbI2 is 1 mol / L, FAI is 0.85 mol / L, and NH4Cl is 0.3 mol / L. Take the prepared perovskite precursor solution and spin-coat it evenly on the transport layer prepared in this embodiment. When spin-coating, the parameters of the spin coater are set as an acceleration of 500 rpm / s, a rotation speed of 3500 rpm, and a time of 40 s. Then transfer the spin-coated wet film to a vacuum device, quickly evacuate to below 20 Pa and maintain for 20 s, then take out the film, place the film on a hot stage at 160 °C for annealing for 2 min, and then transfer the film to a hot stage at 130 °C for annealing for 15 min to obtain a perovskite film with a thickness of 380 nm. Evaporate a 40 nm C60 electron transport layer on the surface of the perovskite film prepared in this embodiment.

[0049] Transfer the obtained product to a thermal evaporation device. Under the condition that the vacuum degree reaches 1×10 -5 Pa, evaporate a gold electrode (Au) on the surface of the C60 electron transport layer, and the thickness of the gold electrode is 100 nm to obtain a perovskite solar cell.

[0050] Example 3

[0051] This embodiment proposes a transport layer, and its preparation method is as follows: Clean a 3*3 cm ITO substrate (the thickness of polyethylene naphthalate (PEN) is 0.5 mm, and the thickness of the ITO film layer is 100 nm). Add nickel oxide nanoparticles to water and ultrasonically disperse for 10 min to form a first solution with a concentration of 30 wt%. Dissolve polyacrylonitrile in a DMF solution and stir at room temperature for 10 minutes to form a second solution with a concentration of 8 wt%. Mix the first solution and the second solution in equal volumes to obtain a transport layer solution. Use a doctor blade method (5 mm / s) to scrape the transport layer solution on the surface of the above ITO substrate; and dry it on a hot stage at 100 °C for 10 min to obtain a transport layer with a thickness of 20 nm. Among them, the contact angle of the transport layer in this embodiment is tested, and the contact angle of the transport layer is 10.7°.

[0052] Prepare a perovskite layer precursor solution, where the perovskite layer precursor solution includes DMF as the solvent, and CsBr, PbI2, FAI, and NH4Cl are added. Among them, in the perovskite layer precursor solution, CsBr is 0.15 mol / L, PbI2 is 1 mol / L, FAI is 0.85 mol / L, and NH4Cl is 0.3 mol / L. Take the prepared perovskite precursor solution and spin-coat it evenly on the transport layer prepared in this embodiment. When spin-coating, the parameters of the spin coater are set as an acceleration of 500 rpm / s, a rotation speed of 3500 rpm, and a time of 40 s. Then transfer the spin-coated wet film to a vacuum device, quickly evacuate to below 20 Pa and maintain for 20 s, then take out the film, place the film on a hot stage at 160 °C for annealing for 2 min, and then transfer the film to a hot stage at 130 °C for annealing for 15 min to obtain a 380 nm perovskite film. Evaporate a 40 nm C60 electron transport layer on the surface of the perovskite film prepared in this embodiment.

[0053] Transfer the obtained product to a thermal evaporation device. Under the condition that the vacuum degree reaches 1×10 -5 Pa, evaporate a gold electrode (Au) on the surface of the C60 electron transport layer, and the thickness of the gold electrode is 100 nm to obtain a perovskite solar cell.

[0054] Example 4

[0055] This embodiment proposes a transport layer, and its preparation method is as follows: Clean a 3*3 cm ITO substrate (the thickness of polyethylene naphthalate (PEN) is 0.5 mm, and the thickness of the ITO film layer is 100 nm). Add nanosized tin oxide to water and ultrasonically disperse it for 10 min to obtain a first solution with a concentration of 20 wt%. Dissolve polyacrylonitrile in a DMF solution and stir at room temperature for 10 minutes to form a second solution with a concentration of 6 wt%. Mix the first solution and the second solution in equal volumes to obtain a transport layer solution. Use a doctor blade method (5 mm / s) to scrape the transport layer solution on the surface of the above ITO substrate; and dry it on a hot stage at 100 °C for 10 min to obtain a transport layer with a thickness of 15 nm. Among them, the contact angle of the transport layer in this embodiment is tested, and the contact angle of the transport layer is 10.7°.

[0056] Prepare a perovskite layer precursor solution, where the perovskite layer precursor solution includes DMF as the solvent, and CsBr, PbI2, FAI, and NH4Cl are added. Among them, in the perovskite layer precursor solution, CsBr is 0.15 mol / L, PbI2 is 1 mol / L, FAI is 0.85 mol / L, and NH4Cl is 0.3 mol / L. Take the prepared perovskite precursor solution and spin-coat it evenly on the transport layer prepared in this embodiment. When spin-coating, the parameters of the spin coater are set as an acceleration of 500 rpm / s, a rotation speed of 3500 rpm, and a time of 40 s. Then transfer the spin-coated wet film to a vacuum device, quickly evacuate to below 20 Pa and maintain it for 20 s. Subsequently, take out the film, place the film on a hot stage at 160 °C for annealing for 2 min, and then transfer the film to a hot stage at 130 °C for annealing for 15 min to obtain a 380 nm perovskite film.

[0057] Transfer the obtained product and use the doctor blade method to prepare a PTAA hole transport layer and evaporate a gold electrode (Au) on the surface. The thickness of the gold electrode is 100 nm to obtain a perovskite solar cell.

[0058] Comparative Example 1

[0059] This comparative example proposes a transport layer, and its preparation method is as follows: Clean a 3*3 cm ITO substrate (the thickness of polyethylene naphthalate (PEN) is 0.5 mm, and the thickness of the ITO film layer is 100 nm). Add nanosized nickel oxide to water and ultrasonically disperse it for 10 min to obtain a first solution with a concentration of 30 wt%. Use a doctor blade method (5 mm / s) to scrape the first solution on the surface of the above ITO substrate; and dry it on a hot stage at 100 °C for 10 min to obtain a transport layer with a thickness of 20 nm. Among them, the contact angle of the transport layer in this embodiment is tested, and the contact angle of the transport layer is 27°.

[0060] Prepare a perovskite layer precursor solution, where the solvent in the perovskite layer precursor solution is DMF, and CsBr, PbI2, FAI, and NH4Cl are added. In the perovskite layer precursor solution, CsBr is 0.15 mol / L, PbI2 is 1 mol / L, FAI is 0.85 mol / L, and NH4Cl is 0.3 mol / L. Take the prepared perovskite precursor solution and spin-coat it evenly on the transport layer prepared in this comparative example. When spin-coating, the parameters of the spin coater are set as an acceleration of 500 rpm / s, a rotation speed of 3500 rpm, and a time of 40 s. Then transfer the spin-coated wet film to a vacuum device, quickly evacuate to below 20 Pa and maintain for 20 s. Subsequently, take out the film, place the film on a hot stage at 160 °C for annealing for 2 min, and then transfer the film to a hot stage at 130 °C for annealing for 15 min to obtain a 380-nm perovskite film; evaporate a 40-nm C60 electron transport layer on the surface of the perovskite film prepared in this comparative example.

[0061] Transfer the obtained product to a thermal evaporation device. Under the condition that the vacuum degree reaches 1×10 -5 Pa, evaporate a gold electrode (Au) on the surface of the C60 electron transport layer. The thickness of the gold electrode is 100 nm to obtain a perovskite solar cell.

[0062] Experimental example

[0063] Use PCE to test the current density-voltage (JV) curves of the flexible perovskite cells prepared in Examples 1-3 and Comparative Example 1. The test is completed on a kethley 2400 system; test conditions: the simulated light intensity is 100 mW cm -2 (AM1.5G), the scanning rate is 0.1 V s -1 (the step size is 0.02 V and the time delay is 200 ms), the scanning range is from 1.2 V to -0.2 V, and the power output of the xenon lamp is calibrated by a NERL (National Renewable Energy Laboratory) standard KG5 standard Si cell. The test results are shown in Table 1.

[0064] Table 1 Detection results of flexible perovskite cells in each example and comparative example

[0065] Open-circuit voltage (V) <![CDATA[Short-circuit current (mA / cm 2 )]]> Fill factor (%) Photoelectric conversion efficiency (%) Example 1 1.13 24.8 79.1 22.17 Example 2 1.15 25.1 81.1 23.41 Example 3 1.14 24.8 81.5 23.04 Example 4 1.16 25.2 78.3 22.89 Comparative example 1.07 23.0 70.0 17.23

[0066] Among them, the flexible perovskite cells prepared in Examples 1-3 and Comparative Example 1 are bent with a cylinder with a bending radius of 10 mm and repeated 1000 times. The loss of their photoelectric conversion efficiency is shown in Table 2.

[0067] Table 2 After bending of the flexible perovskite cells prepared in Examples 1-3 and Comparative Example 1

[0068]

[0069]

[0070] As can be seen from Table 1-2, the transport layer of the present application has good interfacial contact and mechanical properties, improving the quality of the charge transport layer compared with the related art; the flexible perovskite battery obtained by applying the transport layer has good optoelectronic conversion performance and mechanical properties.

[0071] It should be noted that in the description of the present application, the terms "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying relative importance. In addition, in the description of the present application, unless otherwise specified, the meaning of "a plurality" is two or more.

[0072] Any process or method description shown in the flowchart or described in other ways herein can be understood to represent a module, segment, or portion of code including one or more executable instructions for implementing a specific logical function or process. The scope of the preferred embodiments of the present application includes additional implementations, where the functions can be executed in a substantially simultaneous manner or in a reverse order according to the functions involved, rather than in the order shown or discussed, which should be understood by those skilled in the technical field to which the embodiments of the present application belong.

[0073] In the description of this specification, the descriptions with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples", etc. mean that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in a suitable manner in any one or more embodiments or examples.

[0074] Although the embodiments of the present application have been shown and described above, it can be understood that the above embodiments are exemplary and should not be construed as limiting the present application. Those of ordinary skill in the art can make changes, modifications, substitutions, and variations to the above embodiments within the scope of the present application.

Claims

1. A method for preparing a transmission layer, characterized in that: Adding a nanocrystalline charge transport material into a first solvent to obtain a first solution having a concentration of 1 wt % to 30 wt %; Among them, nanocrystalline charge transport materials include nickel oxide and tin oxide; Adding polyacrylonitrile to the second solvent to obtain a second solution with a concentration of 0.1 wt % to 10 wt %; Mixing equal volumes of the first solution and the second solution to obtain a transmission layer solution; The transport layer solution is prepared into a transport layer.

2. The preparation method according to claim 1, characterized in that The first solvent is an aqueous solution; And / or, the aqueous phase solution includes water and / or ethanol.

3. The preparation method according to claim 1, characterized in that: The second solvent is an organic solution; And / or, the organic solution comprises N,N-dimethylformamide or a sulfur-containing organic compound. And / or, the sulfur-containing organic compound is dimethyl sulfoxide.

4. The preparation method according to any one of claims 1 to 3, characterized in that: The transmission layer solution is formed into a coating by spin coating or blade coating, and dried and shaped to form a transmission layer; The drying parameters of the coating are 80-150° C. and drying for 10-15 minutes.

5. The preparation method according to claim 4, characterized in that: The transmission layer solution is scraped on the substrate surface at a speed of 5 mm / s-10 mm / s to form the coating.

6. The preparation method according to claim 4, characterized in that: The thickness of the transmission layer is 10-25 nm.

7. A transport layer, characterized in that: Prepared by the method described in any one of claims 1 to 6.

8. A flexible perovskite battery, characterized in that: Comprising the use of a transport layer as claimed in claim 7.

9. The flexible perovskite battery according to claim 8, characterized in that: The flexible perovskite battery also includes a substrate, a semiconductor material layer, a perovskite layer, a second charge transport layer and a metal layer.

10. The flexible perovskite battery according to claim 8, characterized in that: The transport layer is located between the semiconductor material layer and the perovskite layer.

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