Perovskite solar cell and its manufacturing method

Abstract

The present application provides a perovskite solar cell comprising a transparent conductive glass substrate, an electron transport layer, a perovskite light absorbing layer, a hole transport layer, and an electrode, wherein a metal fluoride layer is provided between the electron transport layer and the perovskite light absorbing layer, and the thickness of the metal fluoride layer is greater than 0 and less than or equal to 3 nm, preferably 1 nm-3 nm. The present application further provides a method for producing the perovskite solar cell.

Description

[Technical field]

[0001] The present application relates to the technical field of solar cells, and in particular to perovskite solar cells and methods for manufacturing the same. [Background technology]

[0002] With the rapid development of the new energy field, solar cells have been widely applied in the fields of military, space, industry, commerce, agriculture, communications, etc. Perovskite solar cells have gradually become the focus of research on next-generation solar cells due to their advantages such as high photoelectric conversion efficiency, simple manufacturing process, low production cost and material cost.

[0003] Perovskite solar cells have been developed very much, and there are higher requirements for their photoelectric conversion efficiency and long-term use stability. Analysis shows that the subsequent improvement in photoelectric conversion efficiency is mainly based on the improvement of the fill factor. The fill factor of the device is mainly related to the contact resistance and parallel resistance of the entire device, and the smaller the contact resistance and the higher the parallel resistance, the higher the fill factor. However, further improvement of the contact resistance is desired for current perovskite solar cells. Summary of the Invention [Problem to be solved by the invention]

[0004] The present application has been made in view of the above-mentioned problems, and has an object to provide a perovskite solar cell having low contact resistance and high photoelectric conversion efficiency. [Means for solving the problem]

[0005] To achieve the above object, the present application provides a perovskite solar cell and a method for manufacturing the same.

[0006] A first aspect of the present application provides a perovskite solar cell comprising a transparent conductive glass substrate, an electron transport layer, a perovskite light absorbing layer, a hole transport layer, and an electrode, wherein a metal fluoride layer is provided between the electron transport layer and the perovskite light absorbing layer, and the thickness of the metal fluoride layer is greater than 0 and equal to or less than 3 nm, preferably 1 nm to 3 nm.

[0007] As a result, the present application provides an extremely thin metal fluoride layer between the electron transport layer and the perovskite light absorbing layer, thereby reducing the contact resistance of the perovskite solar cell, improving its fill factor, and improving the photoelectric conversion efficiency of the perovskite solar cell.

[0008] In any embodiment, the transparent conductive glass substrate, the electron transport layer, the metal fluoride layer, the perovskite light absorbing layer, the hole transport layer and the electrode are provided in this order from bottom to top.

[0009] In any embodiment, the transparent conductive glass substrate, the hole transport layer, the perovskite light absorbing layer, the metal fluoride layer, the electron transport layer and the electrode are provided in this order from bottom to top.

[0010] In any embodiment, the metal fluoride layer is one or more types selected from alkali metal fluorides and alkaline earth metal fluorides, and preferably, the metal fluoride layer is one or more types selected from lithium fluoride, sodium fluoride, potassium fluoride, rubidium fluoride, cesium fluoride, magnesium fluoride, calcium fluoride, strontium fluoride, and barium fluoride.

[0011] A second aspect of the present application further provides a method for producing a perovskite solar cell, comprising: step 1: providing a transparent conductive glass substrate; step 2: preparing an electron transport layer on the transparent conductive glass substrate; step 3: depositing a metal fluoride layer on the electron transport layer; step 4: preparing a perovskite light absorbing layer on the metal fluoride layer; step 5: preparing a hole transport layer on the perovskite light absorbing layer; and step 6: preparing an electrode on the hole transport layer to obtain a perovskite solar cell, wherein the perovskite solar cell comprises a transparent conductive glass substrate, an electron transport layer, a perovskite light absorbing layer, a hole transport layer, and an electrode, and a metal fluoride layer is provided between the electron transport layer and the perovskite light absorbing layer, and a thickness of the metal fluoride layer is greater than 0 and less than or equal to 3 nm, preferably 1 nm-3 nm.

[0012] A third aspect of the present application provides a method for producing a perovskite solar cell, comprising: step 1: providing a transparent conductive glass substrate; step 2: preparing a hole transport layer on the transparent conductive glass substrate; step 3: preparing a perovskite light absorbing layer on the hole transport layer; step 4: depositing a metal fluoride layer on the perovskite light absorbing layer; step 5: preparing an electron transport layer on the metal fluoride layer; and step 6: preparing an electrode on the electron transport layer to obtain a perovskite solar cell, wherein the perovskite solar cell comprises a transparent conductive glass substrate, an electron transport layer, a perovskite light absorbing layer, a hole transport layer, and an electrode, and a metal fluoride layer is provided between the electron transport layer and the perovskite light absorbing layer, and a thickness of the metal fluoride layer is greater than 0 and less than or equal to 3 nm, preferably 1 nm-3 nm.

[0013] As a result, the method of the present application can produce the perovskite solar cell of the present application at low cost and with high efficiency through simple steps.

[0014] In any of the embodiments, in the method according to the second aspect of the present application and the method according to the third aspect of the present application, the deposition rate of the metal fluoride layer is 0.01-0.05 Å / s. When the deposition rate is within the predetermined range, a dense and uniform metal fluoride layer can be obtained. [Brief description of the drawings]

[0015] [Figure 1] FIG. 1 is a schematic diagram of a perovskite solar cell according to one embodiment of the present application. [Diagram 2] FIG. 2 is a schematic diagram of a perovskite solar cell according to another embodiment of the present application. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0016] Hereinafter, the embodiments specifically disclosing the perovskite solar cell and the manufacturing method thereof according to the present application will be described in detail with reference to the drawings as appropriate. However, more detailed explanation than necessary may be omitted. For example, detailed explanation of already well-known matters and duplicate explanation of substantially the same configuration may be omitted. This is to avoid the following explanation becoming unnecessarily redundant and to facilitate understanding by those skilled in the art. Note that the attached drawings and the following explanation are provided to enable those skilled in the art to fully understand the present application, and are not intended to limit the subject matter described in the claims.

[0017] The "ranges" disclosed herein are defined in the form of lower and upper limits, and a given range is defined by selecting one lower limit and one upper limit, and the selected lower and upper limits define the boundaries of the particular range. Ranges defined in this manner may or may not include the end values ​​and may be arbitrarily combinable, i.e., any lower limit may be combined with any upper limit to form a range. For example, if ranges of 60-120 and 80-110 are listed for a particular parameter, then the ranges of 60-110 and 80-120 are also contemplated. Also, if a minimum range value 1, a minimum range value 2, a maximum range value 3, a maximum range value 4, and a maximum range value 5 are listed, then the ranges of 1-3, 1-4, 1-5, 2-3, 2-4, and 2-5 are all contemplated. In this application, unless otherwise stated, the numerical range "ab" stands for any combination of real numbers between a and b, where a and b are both real numbers. For example, a numerical range of "0-5" indicates that the text enumerates all real numbers between "0-5" and "0-5" is merely an abbreviation for combinations of these numbers. Furthermore, expressing a parameter as an integer of 2 or greater is equivalent to disclosing that the parameter is an integer such as 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, etc.

[0018] Unless otherwise stated, all embodiments and optional embodiments in the present application can be combined with each other to form a new technical solution.

[0019] Unless otherwise stated, all technical features and optional technical features in the present application can be combined with each other to form a new technical solution.

[0020] Unless otherwise stated, all steps in the present application may be performed in sequence, may be performed randomly, and preferably in sequence. For example, the method includes steps (a) and (b), which indicates that the method may include steps (a) and (b) performed sequentially, or may include steps (b) and (a) performed sequentially. For example, the method may further include step (c), and when indicating that step (c) may be added to the method in any order, for example, the method may include steps (a), (b) and (c), may include steps (a), (c) and (b), may include steps (c), (a) and (b), etc.

[0021] Unless otherwise stated, the terms "comprise" and "include" used in this application indicate an open system and may also be closed systems. For example, the terms "comprise" and "include" mean that the composition may further comprise or include other components not listed, or may only comprise or include the listed components.

[0022] In this application, unless otherwise stated, the term "or" is inclusive. For example, the phrase "A or B" means "A, B, or both A and B." More specifically, A being true (or existing) and B being false (or not existing), A being false (or not existing) and B being true (or existing), or both A and B being true (or existing) all satisfy the condition "A or B."

[0023] The photoelectric conversion efficiency of conventional perovskite solar cells has reached 25.5%, and both the current density and open circuit voltage have been significantly improved. Analysis shows that the subsequent improvement of photoelectric conversion efficiency is mainly based on the improvement of the fill factor. The fill factor of the device is mainly related to the contact resistance and parallel resistance of the entire device, and the smaller the contact resistance and the higher the parallel resistance, the higher the fill factor of the device. At present, the parallel resistance is mainly improved by reducing the defect level density of the entire device, and improving the conductivity, mobility, etc. is an effective way to reduce the contact resistance.

[0024] After extensive experimentation, the inventors have discovered that providing an ultra-thin metal fluoride layer between the electron transport layer and the perovskite light absorbing layer can reduce the contact resistance and improve the fill factor of perovskite solar cells.

[0025] In one embodiment of the present application, the present application provides a perovskite solar cell comprising a transparent conductive glass substrate, an electron transport layer, a perovskite light absorbing layer, a hole transport layer, and an electrode, wherein a metal fluoride layer is provided between the electron transport layer and the perovskite light absorbing layer, and the thickness of the metal fluoride layer is greater than 0 and less than or equal to 3 nm, preferably 1 nm to 3 nm.

[0026] Although the mechanism is unclear, the applicant unexpectedly discovered that by providing an ultra-thin metal fluoride layer between the electron transport layer and the perovskite light absorbing layer, the electron transport layer can be n-type doped and the Schottky barrier remaining at the interface between the electron transport layer and the perovskite light absorbing layer can be effectively removed, thereby reducing the contact resistance of the perovskite solar cell, improving its fill factor, and ultimately improving the photoelectric conversion efficiency of the perovskite solar cell.

[0027] In some embodiments, a transparent conductive glass substrate 101, a hole transport layer 102, a perovskite light absorbing layer 103, a metal fluoride layer 104, an electron transport layer 105, and an electrode 106 are provided in this order from bottom to top, as shown in Figure 1. A perovskite solar cell thus configured is generally referred to as an inverted perovskite solar cell.

[0028] In some embodiments, a transparent conductive glass substrate 201, an electron transport layer 202, a metal fluoride layer 203, a perovskite light absorbing layer 204, a hole transport layer 205 and an electrode 206 are provided in this order from bottom to top, as shown in Figure 2. A perovskite solar cell thus provided is generally called a positive perovskite solar cell.

[0029] In the present embodiment, the thickness of the metal fluoride layer is detected by a film thickness detector attached to a vacuum deposition apparatus.

[0030] In some embodiments, the metal fluoride layer is one or more selected from alkali metal fluorides and alkaline earth metal fluorides, preferably the metal fluoride layer is one or more selected from lithium fluoride, sodium fluoride, potassium fluoride, rubidium fluoride, cesium fluoride, magnesium fluoride, calcium fluoride, strontium fluoride, and barium fluoride.

[0031] In some embodiments, the metal fluoride layer may be a simple metal fluoride or a mixed metal fluoride.

[0032] In some embodiments, the transparent conductive glass substrate comprises glass and a transparent conductive oxide, the transparent conductive oxide being selected from fluorine-doped tin oxide (FTO), indium tin oxide (ITO), aluminum-doped zinc oxide (AZO), boron-doped zinc oxide (BZO), indium zinc oxide (IZO), etc., the glass has a thickness of 1.1 mm-2.2 mm, and the transparent conductive oxide has a thickness of 100 nm-800 nm.

[0033] In some embodiments, the perovskite light absorbing layer material has the formula ABX3 or A2CDX6, where A is an inorganic or organic or mixed organic-inorganic cation, optionally including a methylamine group (CH3NH3 + )(MA + ), amidino group (HC(NH2)2 + )(FA + ), Cesium ion (Cs + ) and rubidium (Rb + ), and more preferably, at least one of the methylamine group (CH3NH3 + ) or amidino group (HC(NH2)2 + ) where B is an inorganic or organic or mixed organic-inorganic cation, preferably a divalent metal ion Pb 2+and Sn 2+ and C is an inorganic or organic or mixed organic-inorganic cation, preferably a monovalent metal ion Ag + etc., where D is an inorganic or organic or mixed organic-inorganic cation, preferably a trivalent metal ion Bi 3+ X is an inorganic or organic or organic-inorganic mixed anion, preferably at least one or more of a halogen anion and an acetate ion, more preferably a chloride ion (Cl - ), bromide ion (Br - ) or iodine ion (I - ).

[0034] In some embodiments, the material of the perovskite light absorbing layer is FA 0.83 Cs 0.17 It is selected from PbI3 and FAPbI3.

[0035] In some embodiments, the bandgap of the perovskite absorber layer is 1.20-2.30 eV.

[0036] In some embodiments, the perovskite absorber layer has a thickness of 200-1000 nm.

[0037] In some embodiments, the material of the electron transport layer is [6,6]-phenyl-C 61 -Methyl butyrate (PC 61 BM), [6,6]-phenyl-C 71 -Methyl butyrate (PC 71 The materials include at least one of fullerene C60 (C60), fullerene C70 (C70), tin dioxide (SnO2), zinc oxide (ZnO), and their derivatives, and doped or inactivated materials thereof.

[0038] In some embodiments, the electron transport layer has a thickness of 20 nm-50 nm.

[0039] In some embodiments, the material of the hole transport layer is poly[bis(4-phenyl)(2,4,6-trimethylphenyl)amine] (PTAA), 2,2′,7,7′-tetrakis[N,N-di(4-methoxyphenyl)amino]-9,9′-spirobifluorene (Spiro-OMeTAD), poly-3-hexylthiophene (P3HT), tripterene-cored triphenylamine (H101), 3,4-ethylenedioxythiophene-methoxytriphenylamine (H102), 3,4-ethylenedioxythiophene-methoxytri ... The materials include at least one of materials such as diphenylamine (EDOT-OMeTPA), N-(4-aniline)carbazole-spirobifluorene (CzPAF-SBF), poly(3,4-ethylenedioxythiophene):poly(styrenesulfonic acid) (PEDOT:PSS), polythiophene, nickel oxide (NiOx), molybdenum oxide (MoO3), cuprous iodide (CuI), cuprous oxide (Cu2O), and their derivatives, and doped or inactivated materials thereof.

[0040] In some embodiments, the thickness of the hole transport layer is 10 nm-40 nm for inverted perovskite solar cells and 100 nm-300 nm for positive perovskite solar cells.

[0041] In some embodiments, the material of the electrodes is an organic or inorganic or mixed organic-inorganic conductive material, preferably Ag, Cu, C, Au, Al, ITO, AZO, BZO or IZO.

[0042] In some embodiments, the electrode has a thickness of 60 nm-80 nm.

[0043] In some embodiments, corresponding modification layers can be interposed between any of the above layers.

[0044] In one embodiment of the present application, there is provided a method for producing a perovskite solar cell, comprising: step 1: providing a transparent conductive glass substrate; step 2: preparing an electron transport layer on the transparent conductive glass substrate; step 3: depositing a metal fluoride layer on the electron transport layer; step 4: preparing a perovskite light absorbing layer on the metal fluoride layer; step 5: preparing a hole transport layer on the perovskite light absorbing layer; and step 6: preparing an electrode on the hole transport layer to obtain a perovskite solar cell, wherein the perovskite solar cell comprises a transparent conductive glass substrate, an electron transport layer, a perovskite light absorbing layer, a hole transport layer, and an electrode, a metal fluoride layer is provided between the electron transport layer and the perovskite light absorbing layer, and a thickness of the metal fluoride layer is greater than 0 and less than or equal to 3 nm, preferably 1 nm-3 nm.

[0045] In one embodiment of the present application, there is provided a method for producing a perovskite solar cell, comprising: step 1: providing a transparent conductive glass substrate; step 2: producing a hole transport layer on the transparent conductive glass substrate; step 3: producing a perovskite light absorbing layer on the hole transport layer; step 4: depositing a metal fluoride layer on the perovskite light absorbing layer; step 5: producing an electron transport layer on the metal fluoride layer; and step 6: producing an electrode on the electron transport layer to obtain a perovskite solar cell, wherein the perovskite solar cell comprises a transparent conductive glass substrate, an electron transport layer, a perovskite light absorbing layer, a hole transport layer, and an electrode, a metal fluoride layer is provided between the electron transport layer and the perovskite light absorbing layer, and a thickness of the metal fluoride layer is greater than 0 and less than or equal to 3 nm, preferably 1 nm-3 nm.

[0046] The method of the present application can produce the perovskite solar cells of the present application with simple steps, low cost and high efficiency.

[0047] In some embodiments, when depositing the metal fluoride layer, the deposition rate is 0.01-0.05 Å / s.

[0048] When the deposition rate is within a certain range, a dense and uniform metal fluoride layer can be obtained. When the deposition rate is too fast, an island-like metal fluoride layer can be obtained, which may affect the effect, and when the deposition rate is too slow, the deposition takes too long, which is likely to cause the decomposition or peeling of the bottom layer material. Therefore, when the deposition rate is too fast or too slow, a continuous and uniform metal fluoride layer may not be formed.

[0049] In some embodiments, in order to deposit the metal fluoride layer at a stable deposition rate, the 1 nm metal fluoride obtained in the initial deposition is discarded during the deposition process. This process is realized by a shielding plate built into the deposition device, which can be opened and closed by key operation of the device. Before the initial deposition of the metal fluoride, the shielding plate is closed, 1 nm of the metal fluoride is deposited, and then the shielding plate is opened, and 1 nm of the metal fluoride is deposited on the sheet. Then, the shielding plate is closed again, and the vacuum is drawn for 30 minutes, and further subsequent operations are performed to prevent interference effects of the metal fluoride deposition material.

[0050] In some embodiments, the hole transport layer, the perovskite light absorbing layer, the electron transport layer, and the electrodes can be fabricated by methods conventional in the art. EXAMPLES

[0051] The following examples of the present application are described. The following examples are illustrative and are merely for the purpose of explaining the present application, and cannot be understood as limiting the present application. In the examples, specific techniques or conditions are not specified, and are carried out according to techniques or conditions described in the literature in this field, or according to the product specifications. Reagents or equipment used without specifying the manufacturer are all commercially available ordinary products.

[0052] Example 1-1 Step 1: Take a 2.0cm x 2.0cm ITO conductive glass (total thickness 1.1mm, of which the ITO is 100nm thick), remove 0.35cm of ITO from each of the opposing ends by laser etching to expose the glass substrate, and ultrasonically clean the etched ITO conductive glass three times in succession with water, acetone, and isopropanol. After ultrasonic cleaning, spray the ITO conductive glass with a nitrogen gun to dry it, and then place it in a UV ozone machine for further cleaning.

[0053] Step 2: Spin-coat 2 mg / mL chlorobenzene solution of PTAA on the ITO conductive glass after UV ozone treatment at a rate of 5000 rpm, and anneal it on a hot stage at 100 °C for 10 min to obtain a hole transport layer, the thickness of which is 20 nm.

[0054] Step 3: Spin-coat the perovskite precursor solution on the prepared hole transport layer at a rotation speed of 5000 rpm. The perovskite precursor solution is a 4:1 volume ratio of N,N-dimethylformamide and dimethylsulfoxide as a solvent, containing 1.2 mol / L lead iodide, 1.0 mol / L formamidinium hydroiodide and 0.2 mol / L cesium iodide, annealed at 100°C for 30 minutes, cooled to room temperature, and then annealed with FA. 0.83 Cs 0.17 A PbI3 perovskite light absorbing layer is obtained, and its thickness is 550 nm.

[0055] Step 4: In the vacuum deposition machine, 5 × 10 -4 At a vacuum degree of 20 Pa, 1 nm of lithium fluoride is deposited on the perovskite light absorbing layer at a rate of 0.02 Å / s to obtain a metal fluoride layer. During the deposition process, care is taken to discard the 1 nm of lithium fluoride obtained in the initial deposition. After the 1 nm of lithium fluoride is deposited, a shield is placed over the device and the device is evacuated for 30 minutes before carrying out the subsequent operations.

[0056] Step 5: In a vacuum deposition machine, 30 nm of fullerene C60 is deposited on the subsequently prepared metal fluoride layer at a rate of 0.05 Å / s to obtain an electron transport layer.

[0057] Step 6: In a vacuum deposition machine, 80 nm of Cu is deposited on the subsequently prepared electron transport layer at a rate of 0.1 Å / s to obtain an electrode.

[0058] Through the above steps, the perovskite solar cell according to the present application is obtained.

[0059] Examples 1-2 and 1-3 The fabrication of the perovskite solar cell was generally carried out with reference to Example 1-1, except that in step 4, the thicknesses of the metal fluoride layers were 2 nm and 3 nm, respectively.

[0060] Examples 1-4 The manufacture of a perovskite solar cell was generally carried out with reference to Example 1-1, except that in step 4, the metal fluoride was potassium fluoride.

[0061] Examples 1-5 The preparation of a perovskite solar cell was generally carried out with reference to Example 1-1, except that in step 4, the metal fluoride was magnesium fluoride.

[0062] Comparative Example 1-1 The manufacture of a perovskite solar cell was generally carried out with reference to Example 1-1, except that step 4 was not performed.

[0063] Comparative Example 1-2 The fabrication of the perovskite solar cell was generally carried out with reference to Example 1-1, except that in step 4, the thickness of the metal fluoride layer was 4 nm.

[0064] Example 2-1 Step 1: Take a 2.0cm x 2.0cm ITO conductive glass (total thickness 1.1mm, ITO thickness 100nm), remove 0.35cm of ITO from each of the opposing ends by laser etching to expose the glass substrate, ultrasonically clean the etched ITO conductive glass three times in succession with water, acetone, and isopropanol, spray the ultrasonically cleaned ITO conductive glass with a nitrogen gun to dry it, and then place it in a UV ozone machine for further cleaning.

[0065] Step 2: Spin-coat 15 wt% SnO2 colloidal solution onto the UV-ozone treated ITO substrate at a rate of 4000 rpm and anneal it on a hot stage at 150 °C for 10 min to obtain a 30 nm thick electron transport layer.

[0066] Step 3: In the vacuum deposition machine, 5 × 10 -4 Lithium fluoride of 1 nm is evaporated onto the electron transport layer at a rate of 0.02 Å / s under a vacuum of 1 Pa to obtain a metal fluoride layer.

[0067] Step 4: Spin-coat the perovskite precursor solution on the prepared metal fluoride layer at a rotation speed of 5000 rpm. The perovskite precursor solution is a 4:1 volume ratio of N,N-dimethylformamide and dimethylsulfoxide as a solvent, contains 1.2 mol / L lead iodide, 1.0 mol / L formamidinium hydroiodide, and 0.2 mol / L cesium iodide, and is annealed at 100° C. for 30 minutes, cooled to room temperature, and then annealed with FA. 0.83 Cs 0.17 A PbI3 perovskite light absorbing layer is obtained, and its thickness is 550 nm.

[0068] Step 5: On the fabricated perovskite light absorbing layer, a chlorobenzene solution of 73 mg / mL Spiro-OMeTAD is spin-coated at a rate of 3000 rpm to obtain a hole transport layer, the thickness of which is 200 nm.

[0069] Step 6: In the vacuum deposition machine, 5 × 10 -4In a vacuum of 0.1 Pa, 80 nm of Au is evaporated onto the hole transport layer at a rate of 0.1 Å / s to obtain an electrode.

[0070] Through the above steps, the perovskite solar cell according to the present application is obtained.

[0071] Examples 2-2 and 2-3 The fabrication of the perovskite solar cell was generally carried out with reference to Example 2-1, except that in step 3, the thicknesses of the metal fluoride layers were 2 nm and 3 nm, respectively.

[0072] Examples 2-4 The manufacture of a perovskite solar cell was generally carried out with reference to Example 2-1, except that in step 3, the metal fluoride was cesium fluoride.

[0073] Examples 2-5 The preparation of a perovskite solar cell was generally carried out with reference to Example 2-1, except that in step 3, the metal fluoride was magnesium fluoride.

[0074] Comparative Example 2-1 The perovskite solar cell was manufactured generally in accordance with Example 2-1, except that step 3 was not performed.

[0075] Comparative Example 2-2 The fabrication of the perovskite solar cell was generally carried out with reference to Example 2-1, except that in step 3, the thickness of the metal fluoride layer was 4 nm.

[0076] Examples 3-1 and 3-2 The preparation of the perovskite solar cell was generally carried out with reference to Example 1-1, except that in step 4, the deposition rates of the metal fluorides were 0.01 Å / s and 0.05 Å / s, respectively.

[0077] Comparative Examples 3-1 and 3-2 The preparation of the perovskite solar cell was generally carried out with reference to Example 1-1, except that in step 4, the deposition rates of the metal fluorides were 0.005 Å / s and 0.06 Å / s, respectively.

[0078] Examples 4-1 and 4-2 The fabrication of the perovskite solar cell was generally carried out with reference to Example 2-1, except that in step 3, the deposition rates of the metal fluorides were 0.01 Å / s and 0.05 Å / s, respectively.

[0079] Comparative Examples 4-1 and 4-2 The preparation of the perovskite solar cell was generally carried out with reference to Example 2-1, except that in step 3, the deposition rates of the metal fluorides were 0.005 Å / s and 0.06 Å / s, respectively.

[0080] Measurement method 1. Contact resistance of perovskite solar cells Standard simulated sunlight (AM1.5G, 100mW / cm 2 ) to measure the cell performance, obtain an IV curve, and automatically read the contact resistance value based on the data from the computer.

[0081] 2. Photoelectric conversion efficiency of perovskite solar cells Standard simulated sunlight (AM1.5G, 100mW / cm 2 ) and the cell performance was measured to obtain an IV curve. The short circuit current Jsc (unit: mA / cm 2 ), open circuit voltage Voc (unit: V), maximum optical output current Jmpp (unit: mA), and maximum optical output voltage Vmpp (unit: V) can be determined from the IV curve and data fed back from the measurement device. The fill factor FF (unit: %) of the battery is calculated using the formula FF = Jsc × Voc / (Jmpp × Vmpp). The photoelectric conversion efficiency PCE (unit: %) of the battery is calculated using the formula PCE = Jsc × Voc × FF / Pw, where Pw is the input power in mW.

[0082] The perovskite solar cells obtained in the above Examples and Comparative Examples were each measured according to the above procedures, and specific values ​​are referred to in Tables 1 to 4.

[0083] [Table 1]

[0084] [Table 2]

[0085] [Table 3]

[0086] [Table 4]

[0087] As can be seen from Tables 1 to 4, by providing an extremely thin metal fluoride layer between the electron transport layer and the perovskite light absorbing layer, the photoelectric conversion efficiency of the perovskite solar cells of all the above examples was higher than that of the perovskite solar cell of the comparative example.

[0088] As can be seen from Table 1, when the thickness of the metal fluoride layer is 1 nm-3 nm, the contact resistance of the inverted perovskite solar cell can be significantly reduced and the photoelectric conversion efficiency of the inverted perovskite solar cell can be improved.

[0089] As can be seen from Table 2, when the thickness of the metal fluoride layer is 1 nm-3 nm, the contact resistance of the positive perovskite solar cell can be significantly reduced and the photoelectric conversion efficiency of the positive perovskite solar cell can be improved.

[0090] As can be seen from Tables 3 and 4, the deposition rate of metal fluoride also affects the performance of inverted and normal perovskite solar cells. When the deposition rate of metal fluoride is 0.01-0.05 Å / s, it can reduce the contact resistance of the perovskite solar cell and improve the photoelectric conversion efficiency of the perovskite solar cell.

[0091] The present application is not limited to the above-mentioned embodiment. The above-mentioned embodiment is an example, and any embodiment having substantially the same configuration as the technical idea within the technical scope of the present application and having similar effects is included in the technical scope of the present application. Furthermore, within the scope of the present application, various modifications that a person skilled in the art can conceive of, and other forms constructed by combining some of the components in the embodiment are also included in the scope of the present application. [Explanation of symbols]

[0092] 101: transparent conductive glass substrate, 102: hole transport layer, 103: perovskite light absorbing layer, 104: metal fluoride layer, 105: electron transport layer, 106: electrode, 201: transparent conductive glass substrate, 202: electron transport layer, 203: metal fluoride layer, 204: perovskite light absorbing layer, 205: hole transport layer, 206: electrode

Claims

1. A perovskite solar cell comprising a transparent conductive glass substrate, an electron transport layer, a perovskite light absorbing layer, a hole transport layer, and an electrode, A perovskite solar cell, wherein a metal fluoride layer is provided between the electron transport layer and the perovskite light absorbing layer, and the thickness of the metal fluoride layer is greater than 0 and less than or equal to 3 nm, preferably 1 nm-3 nm.

2. 2. The perovskite solar cell according to claim 1, wherein the transparent conductive glass substrate, the electron transport layer, the metal fluoride layer, the perovskite light absorbing layer, the hole transport layer and the electrode are provided in this order from bottom to top.

3. 2. The perovskite solar cell according to claim 1, wherein the transparent conductive glass substrate, the hole transport layer, the perovskite light absorbing layer, the metal fluoride layer, the electron transport layer and the electrode are provided in this order from bottom to top.

4. 4. The perovskite solar cell according to claim 1, wherein the metal fluoride layer is one or more selected from alkali metal fluorides and alkaline earth metal fluorides, and preferably the metal fluoride layer is one or more selected from lithium fluoride, sodium fluoride, potassium fluoride, rubidium fluoride, cesium fluoride, magnesium fluoride, calcium fluoride, strontium fluoride, and barium fluoride.

5. A method for producing a perovskite solar cell, comprising the steps of: Step 1: providing a transparent conductive glass substrate; Step 2: preparing an electron transport layer on the transparent conductive glass substrate; Step 3: depositing a metal fluoride layer on the electron transport layer; Step 4: preparing a perovskite light absorbing layer on the metal fluoride layer; Step 5: preparing a hole transport layer on the perovskite light absorbing layer; Step 6: fabricating an electrode on the hole transport layer to obtain a perovskite solar cell; wherein the perovskite solar cell comprises a transparent conductive glass substrate, an electron transport layer, a perovskite light absorbing layer, a hole transport layer, and an electrode, a metal fluoride layer is provided between the electron transport layer and the perovskite light absorbing layer, and the thickness of the metal fluoride layer is greater than 0 and less than or equal to 3 nm, and preferably 1 nm to 3 nm.

6. A method for producing a perovskite solar cell, comprising the steps of: Step 1: providing a transparent conductive glass substrate; Step 2: preparing a hole transport layer on the transparent conductive glass substrate; Step 3: preparing a perovskite light absorbing layer on the hole transport layer; Step 4: depositing a metal fluoride layer on the perovskite light absorbing layer; Step 5: forming an electron transport layer on the metal fluoride layer; Step 6: fabricating an electrode on the electron transport layer to obtain a perovskite solar cell; wherein the perovskite solar cell comprises a transparent conductive glass substrate, an electron transport layer, a perovskite light absorbing layer, a hole transport layer, and an electrode, a metal fluoride layer is provided between the electron transport layer and the perovskite light absorbing layer, and the thickness of the metal fluoride layer is greater than 0 and less than or equal to 3 nm, and preferably 1 nm to 3 nm.

7. The method for producing a perovskite solar cell according to claim 5 or 6, wherein the deposition rate of the metal fluoride layer is 0.01-0.05 Å / s.

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