Back contact type perovskite solar cell

Abstract

The utility model provides a back contact type perovskite solar cell. The back contact type perovskite solar cell comprises a metal oxide conductive transparent layer and an electron transport layer which are distributed in a planar layered manner, the patterned insulating layer is in contact with the electron transfer layer; the patterned copper electrode layer and the copper oxide hole transport layer generated on the surface of the patterned copper electrode layer in situ are located on the patterned insulating layer, and the pattern of the patterned insulating layer is the same as that of the patterned copper electrode layer; the perovskite layer is located on the copper oxide hole transport layer and is in direct contact with the electron transport layer through the hollow area of the patterned insulating layer; and a packaging adhesive film layer which is located on the perovskite layer.

Description

Technical Field

[0001] The utility model relates to the field of solar cells, in particular to a back-contact perovskite solar cell. Background Art

[0002] Solar energy is a renewable, clean and pollution-free form of energy. As the core component of solar energy conversion equipment, the improvement of solar cell performance directly affects the efficiency and economy of solar power generation systems. Among the many solar cell technologies, perovskite solar cells have attracted much attention due to their high photoelectric conversion efficiency, easy preparation and low cost.

[0003] In the traditional structure, the light absorption layer of the perovskite solar cell is located at the top of the cell structure. The transmission of electrons and holes needs to pass through the material layer to reach the electrode, which easily leads to the recombination loss of electrons and holes. The back-contact perovskite solar cell is a new design for the traditional perovskite solar cell structure. The back-contact structure places the light absorption layer on the back of the cell and optimizes the electrode structure, optimizing the transmission path of electrons and holes, so that light directly contacts the electrode after passing through the cell, effectively reducing the recombination loss of electrons and holes, thereby improving the photoelectric conversion efficiency and long-term stability of the cell and effectively reducing the preparation cost of the cell device.

[0004] In the prior art, dense and mesoporous TiO2 is used as the electron transport layer and expensive metal nickel is used as the electrode in the preparation process of the back-contact perovskite solar cells, which makes the carrier splitting efficiency of the prepared back-contact perovskite solar cells low and the energy consumption high. The expensive materials are also not conducive to the commercial development of the back-contact perovskite solar cells.

[0005] In order to overcome the above-mentioned defects of the prior art, the art is in urgent need of a back-contact perovskite solar cell that can improve the photoelectric conversion efficiency while reducing the manufacturing cost of the back-contact perovskite solar cell. Utility Model Content

[0006] A brief summary of one or more aspects is given below to provide a basic understanding of these aspects. This summary is not an exhaustive overview of all conceived aspects, and is neither intended to identify the key or critical elements of all aspects nor to define the scope of any or all aspects. Its only purpose is to give some concepts of one or more aspects in a simplified form as a prelude to a more detailed description that will be given later.

[0007] In order to overcome the above-mentioned defects in the prior art, the utility model provides a back-contact perovskite solar cell, which can reduce the manufacturing cost of the back-contact perovskite solar cell while improving the photoelectric conversion efficiency.

[0008] Specifically, the above-mentioned back-contact perovskite solar cell provided by the utility model includes: a metal oxide conductive transparent layer and an electron transport layer distributed in a planar layer; a patterned insulating layer, the patterned insulating layer is in contact with the electron transport layer; a patterned copper electrode layer and a copper oxide hole transport layer generated in situ on its surface, which is located on the patterned insulating layer, and the pattern of the patterned insulating layer is the same as that of the patterned copper electrode layer; a perovskite layer, the perovskite layer is located on the copper oxide hole transport layer, and is in direct contact with the electron transport layer through the hollow area of ​​the patterned insulating layer; and an encapsulation film layer, the encapsulation film layer is located on the perovskite layer.

[0009] Preferably, in an embodiment of the present invention, the material of the electron transport layer includes SnO2 or ZnO or TiO2.

[0010] Preferably, in an embodiment of the present invention, the thickness of the electron transport layer is 1-70 nm.

[0011] Preferably, in an embodiment of the present invention, the thickness of the patterned copper electrode layer is 70-200 nm.

[0012] Preferably, in an embodiment of the present invention, the sheet resistance of the metal oxide conductive transparent layer is 5-25Ω / sq.

[0013] Preferably, in an embodiment of the present invention, the material of the patterned insulating layer includes Al2O3.

[0014] Preferably, in an embodiment of the present invention, the thickness of the patterned insulating layer is 50-200 nm.

[0015] Preferably, in one embodiment of the present invention, the material chemical formula of the perovskite layer is FA x Cs 1- x PbB y I 3-y , where the size of x is 0.85~1 and the size of y is 0~0.6.

[0016] Preferably, in an embodiment of the present invention, the thickness of the perovskite layer is 1 to 800 nm.

[0017] Preferably, in an embodiment of the present invention, the material of the packaging film layer includes PP or PE or PMMA or silica gel or epoxy resin. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The above features and advantages of the present invention can be better understood after reading the detailed description of the embodiments of the present disclosure in conjunction with the following drawings. In the drawings, the components are not necessarily drawn to scale, and components with similar related properties or features may have the same or similar reference numerals.

[0019] Figure 1 A schematic diagram showing a partial cross section of a back-contact perovskite solar cell provided according to some embodiments of the present utility model;

[0020] Figure 2 A schematic diagram of a pattern of a patterned insulating layer provided according to some embodiments of the utility model is shown;

[0021] Figure 3 A schematic diagram showing current transmission of a back-contact perovskite solar cell provided according to some embodiments of the present utility model is shown; and

[0022] Figure 4 A simplified diagram of an external circuit for a back-contact perovskite solar cell provided according to some embodiments of the utility model is shown.

[0023] Reference numerals:

[0024] 100: Back-contact perovskite solar cells;

[0025] 110: Metal oxide conductive transparent layer;

[0026] 120: electron transport layer;

[0027] 130: patterned insulating layer;

[0028] 140: patterned copper electrode layer;

[0029] 150: copper oxide hole transport layer;

[0030] 160: a perovskite layer; and

[0031] 170: Encapsulation film layer. DETAILED DESCRIPTION

[0032] The present invention is described in detail below in conjunction with the accompanying drawings and specific embodiments. Note that the aspects described below in conjunction with the accompanying drawings and specific embodiments are only exemplary and should not be construed as limiting the scope of protection of the present invention.

[0033] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installation", "connection" and "connection" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0034] In addition, the terms "upper", "lower", "left", "right", "top", "bottom", "horizontal" and "vertical" used in the following description should be understood as the directions shown in the paragraph and the related drawings. Such relative terms are only used for the convenience of description and do not mean that the device described therein must be manufactured or operated in a specific direction, and therefore should not be understood as limiting the present invention.

[0035] It is understood that although the terms "first", "second", "third", etc. may be used herein to describe various components, regions, layers and / or parts, these components, regions, layers and / or parts should not be limited by these terms, and these terms are only used to distinguish different components, regions, layers and / or parts. Therefore, the first component, region, layer and / or part discussed below may be referred to as the second component, region, layer and / or part without departing from some embodiments of the present invention.

[0036] As described above, in the prior art, dense and mesoporous TiO2 is used as the electron transport layer and expensive metal nickel is used as the electrode during the preparation process of the back-contact perovskite solar cells, which makes the prepared back-contact perovskite solar cells have low carrier splitting efficiency and high energy consumption. The expensive materials are also not conducive to the commercial development of the back-contact perovskite solar cells.

[0037] In order to overcome the above-mentioned defects in the prior art, the utility model provides a back-contact perovskite solar cell, which can reduce the manufacturing cost of the back-contact perovskite solar cell while improving the photoelectric conversion efficiency.

[0038] Please refer to Figure 1 , Figure 1 A schematic diagram of a partial cross section of a back-contact perovskite solar cell provided according to some embodiments of the present invention is shown.

[0039] like Figure 1 As shown, the back-contact perovskite solar cell 100 may include a metal oxide conductive transparent layer 110 and an electron transport layer 120 distributed in a planar layer shape.

[0040] The metal oxide conductive transparent layer 110 has a square resistance of 5 to 25 Ω / sq, and the metal oxide conductive transparent layer 110 may include but is not limited to ITO conductive glass, FTO conductive glass, IZO conductive glass, AZO conductive glass, etc. prepared by various methods. An electron transport layer 120 with a thickness of 1 to 70 nm is deposited on the metal oxide conductive transparent layer 110. The material of the electron transport layer 120 may include but is not limited to SnO2 or ZnO or TiO2.

[0041] The back-contact perovskite solar cell 100 may further include a patterned insulating layer 130 with a thickness of 50-200 nm, and the patterned insulating layer 130 is in direct contact with the electron transport layer 120. Preferably, the material of the patterned insulating layer 130 may be Al2O3.

[0042] Please refer to Figure 2 , Figure 2 A schematic diagram of a pattern of a patterned insulating layer provided according to some embodiments of the present utility model is shown.

[0043] like Figure 2 As shown, the pattern of the patterned insulating layer 130 may be stripe-shaped, and there are hollow areas between the stripes and between each stripe and the edge of the electron transport layer 120 , and the electron transport layer 120 below the patterned insulating layer 130 is exposed through the hollow areas. Figure 1 The partial cross section of the back-contact perovskite solar cell 100 shown may be a cross section between two stripes of the patterned insulating layer 130. Those skilled in the art will appreciate that Figure 2 The pattern shown may also be any other shape according to actual needs.

[0044] The patterned copper electrode layer 140 of the back-contact perovskite solar cell 100 is located above the patterned insulating layer 130, and the patterned insulating layer 130 has the same pattern as the patterned copper electrode layer 140. The thickness of the patterned copper electrode layer 140 can be 70 to 200 nm, and is formed by thermal evaporation, magnetron sputtering, or electron beam evaporation. Copper electrodes are cheaper than nickel electrodes, which can further reduce the manufacturing cost of the back-contact perovskite solar cell 100. In addition, copper has a higher electrical conductivity than nickel, which can more effectively collect and conduct photocurrent, reduce the loss of electrical energy, and thus improve the overall efficiency of the solar cell.

[0045] The surface of the patterned copper electrode layer 140 is in-situ generated copper oxide (CuO x ) The hole transport layer 150, the copper oxide hole transport layer 150 can be directly generated by heating and annealing the patterned copper electrode layer 140,

[0046] The patterned insulating layer 130 separates the patterned copper electrode layer 140 and the copper oxide hole transport layer 150 on its surface from the electron transport layer 120. The patterned copper electrode layer 140 does not directly contact the electron transport layer 120, and similarly, the copper oxide hole transport layer 150 on the surface of the patterned copper electrode layer 140 does not directly contact the electron transport layer 120.

[0047] The perovskite layer 160 with a thickness of 1-800 nm is located on the copper oxide hole transport layer 150. The perovskite layer 160 is not only in direct contact with the copper oxide hole transport layer 150, but also in direct contact with the electron transport layer 120 through the hollowed-out areas of the patterned insulating layer 130 and the patterned copper electrode layer 140.

[0048] Here, the material chemical formula of the perovskite layer 160 is FA x Cs 1-x PbB y I 3-y , where the size of x is 0.85~1 and the size of y is 0~0.6.

[0049] The encapsulation film layer 170 is disposed above the perovskite layer 160 . The material of the encapsulation film layer 170 includes, but is not limited to, PP, PE, PMMA, silicone, and epoxy resin.

[0050] Please refer to Figure 3 , Figure 3 A schematic diagram of current transmission of a back-contact perovskite solar cell provided according to some embodiments of the utility model is shown.

[0051] like Figure 3 As shown, one side of the encapsulation film layer 170 (i.e., the end where the perovskite layer 160 is located) is the back side of the back-contact perovskite solar cell 100. Light is irradiated through one end of the encapsulation film layer 170 and absorbed by the perovskite layer 160. Then, the generated electrons are directly collected by the metal oxide conductive transparent layer 110 through the electron transport layer 120, and the generated holes are directly collected by the patterned copper electrode layer 140 through the copper oxide hole transport layer 150. Therefore, through the direct contact between the perovskite layer 160 and the electron transport layer 120 and the copper oxide hole transport layer 150, the efficiency of electron and hole transport is greatly improved, thereby improving the photoelectric conversion efficiency.

[0052] In addition, by using copper as an electrode, the work function of the interface between the perovskite layer 160 and the perovskite layer 160 can be adjusted, the carrier extraction barrier can be weakened, and the energy loss of the carriers during the extraction process can be reduced, thereby avoiding the recombination loss caused by the inability to smoothly extract the carriers. In addition, the surface of the copper electrode is directly oxidized to copper oxide as a hole transport layer through the reaction, which improves the efficiency of electron and hole transport, simplifies the preparation process of the copper oxide hole transport layer and reduces the manufacturing cost.

[0053] Please refer to Figure 4 , Figure 4 A simplified diagram of an external circuit for a back-contact perovskite solar cell provided according to some embodiments of the utility model is shown.

[0054] like Figure 4 As shown, in a preferred embodiment, photocurrent can be generated by externally connecting the metal oxide conductive transparent layer 110 to the patterned copper electrode layer 140 .

[0055] In the process of preparing a back-contact perovskite solar cell, an electron transport layer is first deposited on the metal oxide conductive transparent layer, and then a photoresist is coated on the electron transport layer, and the photoresist is exposed and etched to form a pattern area for filling the material of the patterned insulating layer.

[0056] A patterned insulating layer made of Al2O3 is formed in the patterned area, and a patterned copper electrode layer and a copper oxide hole transport layer on its surface are continuously formed on the patterned insulating layer. Here, the formation method of the patterned copper electrode layer includes but is not limited to thermal evaporation or magnetron sputtering or electron beam evaporation. The copper oxide hole transport layer is directly formed on the surface of the patterned copper electrode layer by heating and annealing the patterned copper electrode layer. Preferably, the temperature of the heating annealing can be 250 to 350°C, and the time of the heating annealing can be 5 to 60 minutes.

[0057] After that, the photoresist is washed to expose the electron transport layer. The re-deposited perovskite layer can directly contact the electron transport layer, the patterned insulating layer and the copper oxide hole transport layer. Here, the perovskite layer is in direct contact with the copper oxide hole transport layer, and is in direct contact with the electron transport layer through the hollowed-out area of ​​the patterned insulating layer. The formation method of the perovskite layer includes but is not limited to scraping, spin coating, evaporation, and slit coating. Finally, an encapsulation film layer is formed on the perovskite layer.

[0058] The following is a specific non-limiting preferred embodiment, based on which the back-contact perovskite solar cell and the preparation method thereof proposed in the present invention are further described.

[0059] In this embodiment, firstly, a 40 nm electron transport layer made of SnO2 is deposited on an ITO conductive glass with a square resistance of 20Ω / sq, and PEGDA is coated on the surface of the electron transport layer as a photoresist.

[0060] After the photoresist is exposed and etched, a patterned area is formed. A 100 nm aluminum oxide insulating layer is magnetron sputtered in the patterned area, and a 150 nm patterned copper electrode layer is magnetron sputtered. Then, the patterned copper electrode layer is heated and annealed at 200 ° C for 30 min to generate a copper oxide (CuO) layer with a thickness of about 30 nm in situ on the patterned copper electrode layer. x )Hole transport layer.

[0061] Then, the photoresist was ultrasonically washed with deionized water as a developer, and a 650nm perovskite layer was coated using an anti-solvent-free method. The material chemical formula of the perovskite layer is Cs 0.1 FA 0.9 I3. Finally, PMMA is coated as a packaging film layer.

[0062] Thus, the prepared back-contact perovskite solar cell includes a planar layered metal oxide conductive transparent layer, an electron transport layer, a patterned insulating layer, a patterned copper electrode layer on the patterned insulating layer, and a copper oxide hole transport layer generated in situ on its surface. The perovskite layer can be deposited in the hollow area of ​​the patterned insulating layer, the perovskite layer is in direct contact with the copper oxide hole transport layer and the electron transport layer, and the perovskite layer is above the encapsulation film layer.

[0063] The back-contact perovskite solar cell prepared in this embodiment has excellent performance, with an open circuit voltage (Voc) of 1.10 V and a short circuit current density (Jsc) of 17.26 mA / cm 2 , the fill factor (FF) is 57.63% and the photoelectric conversion efficiency (PCE) is 10.94%.

[0064] The following is another specific non-limiting preferred embodiment. In this embodiment, a 40 nm thick electron transport layer made of ZnO is first deposited on FTO conductive glass with a square resistance of 15 Ω / sq, and PAA is coated on the surface of the electron transport layer as a photoresist.

[0065] After exposing and etching the photoresist, a pattern area is formed. A 100 nm aluminum oxide insulating layer is magnetron sputtered in the patterned area, and a 150 nm patterned copper electrode layer is magnetron sputtered. The layer is then heated and annealed at 200°C for 30 min, and a 30 nm thick copper oxide hole transport layer is in situ generated on the patterned copper electrode layer.

[0066] Then, the photoresist was ultrasonically washed with deionized water as a developer, and a 700nm perovskite layer was coated using an anti-solvent-free method. The material chemical formula of the perovskite layer is Cs0.05 FA 0.95 I3. Finally, PE is coated as an encapsulation film layer.

[0067] The back-contact perovskite solar cell prepared in this embodiment has excellent performance, with an open circuit voltage (Voc) of 1.07 V and a short circuit current density (Jsc) of 18.37 mA / cm 2 , the fill factor (FF) is 54.71% and the photoelectric conversion efficiency (PCE) is 10.75%.

[0068] In summary, the back-contact perovskite solar cell provided by the utility model can reduce the manufacturing cost of the back-contact perovskite solar cell while improving the photoelectric conversion efficiency.

[0069] The previous description of the disclosure is provided to enable any person skilled in the art to make or use the disclosure. Various modifications to the disclosure will be apparent to those skilled in the art, and the general principles defined herein may be applied to other variations without departing from the spirit or scope of the disclosure. Thus, the disclosure is not intended to be limited to the examples and designs described herein, but should be granted the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A back-contact perovskite solar cell, characterized in that: include: A metal oxide conductive transparent layer and an electron transport layer distributed in a planar layer; a patterned insulating layer, wherein the patterned insulating layer is in contact with the electron transport layer; The patterned copper electrode layer and the copper oxide hole transport layer in-situ generated on the surface thereof are located on the patterned insulating layer, and the patterned insulating layer has the same pattern as that of the patterned copper electrode layer; a perovskite layer, the perovskite layer being located on the copper oxide hole transport layer and directly contacting the electron transport layer through the hollowed-out region of the patterned insulating layer; as well as The encapsulation film layer is located on the perovskite layer.

2. The back-contact perovskite solar cell according to claim 1, characterized in that: The material of the electron transport layer includes SnO2 or ZnO or TiO2.

3. The back-contact perovskite solar cell according to claim 1, characterized in that The thickness of the electron transport layer is 1-70 nm.

4. The back-contact perovskite solar cell according to claim 1, characterized in that The thickness of the patterned copper electrode layer is 70-200 nm.

5. The back-contact perovskite solar cell according to claim 1, characterized in that: The sheet resistance of the metal oxide conductive transparent layer is 5 to 25Ω / sq.

6. The back-contact perovskite solar cell according to claim 1, characterized in that: The material of the patterned insulating layer includes Al2O3.

7. The back-contact perovskite solar cell according to claim 1, characterized in that: The thickness of the patterned insulating layer is 50-200 nm.

8. The back-contact perovskite solar cell according to claim 1, characterized in that: The material chemical formula of the perovskite layer is FA x Cs 1-x PbB y I 3-y , where the size of x is 0.85~1 and the size of y is 0~0.

6.

9. The back-contact perovskite solar cell according to claim 1, characterized in that: The thickness of the perovskite layer is 1 to 800 nm.

10. The back-contact perovskite solar cell according to claim 1, characterized in that: The material of the packaging film layer includes PP or PE or PMMA or silica gel or epoxy resin.

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