Perovskite solar cell, preparation method thereof and electric equipment

Abstract

The invention discloses a perovskite solar cell, a preparation method thereof and electric equipment. The perovskite solar cell comprises a perovskite light absorption layer, an electron transport layer and a resistance reduction layer located between the perovskite light absorption layer and the electron transport layer. Therefore, the resistance reduction layer can reduce the residual Schottky barrier between the interfaces of the perovskite light absorption layer and the electron transport layer, reduce the contact resistance between the perovskite light absorption layer and the electron transport layer, and improve the fill factor of the perovskite solar cell device.

Description

Perovskite solar cell, preparation method thereof, and electrical equipment Technical Field

[0001] The present invention belongs to the technical field of solar cells, and in particular relates to a perovskite solar cell, a preparation method thereof, and electrical equipment. Background Art

[0002] Perovskite solar cells are a new type of solar cell technology that has flourished in recent years. They utilize perovskite-type organic metal halide semiconductors as light-absorbing materials. They belong to the third generation of solar cells, also known as new-concept solar cells. In recent years, perovskite solar cells have attracted significant attention due to their abundant raw material reserves, simple fabrication process, and ability to achieve record-breaking high performance using low-temperature, low-cost processes.

[0003] The contact resistance between film layers in perovskite solar cells directly affects the fill factor of the device. Therefore, it would be of great significance if a perovskite solar cell that can reduce the interface contact resistance could be developed.

[0004] Summary of the Invention

[0005] In view of this, the present invention provides a perovskite solar cell, comprising: a perovskite light-absorbing layer, an electron transport layer, and a resistance-reducing layer located between the perovskite light-absorbing layer and the electron transport layer. The resistance-reducing layer can reduce the residual Schottky barrier at the interface between the perovskite light-absorbing layer and the electron transport layer, thereby reducing the contact resistance between the perovskite light-absorbing layer and the electron transport layer, and improving the fill factor of the perovskite solar cell device.

[0006] According to an embodiment of the present invention, the material forming the resistance-reducing layer includes at least one of a metal sulfide, a metalloid sulfide, and a sulfur-containing organic compound. This effectively reduces the contact resistance between the perovskite light-absorbing layer and the electron transport layer, thereby improving the fill factor of the perovskite solar cell device.

[0007] According to an embodiment of the present invention, the material forming the resistance-reducing layer includes at least one of lithium sulfide, potassium sulfide, magnesium sulfide, arsenic sulfide, indium sulfide, manganese sulfide, and cobalt sulfide, thereby effectively improving the performance of perovskite solar cells.

[0008] According to an embodiment of the present invention, the thickness of the resistance-reducing layer is less than or equal to 3 nm, thereby effectively reducing the contact resistance between the perovskite light-absorbing layer and the electron transport layer, and effectively improving the fill factor of the perovskite solar cell device.

[0009] According to an embodiment of the present invention, the thickness of the resistance-reducing layer is 1 to 3 nm, thereby effectively reducing the residual Schottky barrier at the interface between the perovskite light-absorbing layer and the electron transport layer, and improving the fill factor of the perovskite solar cell device.

[0010] According to an embodiment of the present invention, the perovskite solar cell further comprises a back electrode layer, a transparent electrode layer and a hole transport layer, thereby further improving the performance of the perovskite solar cell.

[0011] According to an embodiment of the present invention, the transparent electrode layer is located on the side of the electron transport layer away from the resistance reduction layer; the hole transport layer is located on the side of the perovskite light absorption layer away from the resistance reduction layer; and the back electrode layer is located on the side of the hole transport layer away from the perovskite light absorption layer. Thus, the structure of the perovskite solar cell is a stacked arrangement of: transparent electrode layer, electron transport layer, resistance reduction layer, perovskite light absorption layer, hole transport layer, and back electrode layer. That is, the perovskite solar cell of the present invention can have a formal device structure.

[0012] According to an embodiment of the present invention, the hole transport layer is located on the side of the perovskite light absorbing layer away from the resistance reduction layer; the transparent electrode layer is located on the side of the hole transport layer away from the perovskite light absorbing layer; and the back electrode layer is located on the side of the electron transport layer away from the resistance reduction layer. Thus, the structure of the perovskite solar cell is a stacked arrangement of: transparent electrode layer, hole transport layer, perovskite light absorbing layer, resistance reduction layer, electron transport layer, and back electrode layer. That is, the perovskite solar cell of the present invention can have an inverted device structure.

[0013] According to an embodiment of the present invention, the perovskite solar cell satisfies at least one of the following conditions: the material forming the transparent electrode layer includes at least one of FTO, ITO, AZO, BZO, and IZO; the chemical formula of the material forming the perovskite light absorption layer is ABX3 or A2CDX6, wherein A is at least one of a methylamine group, a formamidinium group, a cesium ion, and a rubidium ion, B is at least one of a divalent lead ion and a divalent tin ion, C is a monovalent silver ion, D is a trivalent bismuth ion, and X is at least one of a chloride ion, a bromide ion, and an iodide ion; the band gap of the perovskite light absorption layer is 1.20-2.30 eV; the thickness of the perovskite light absorption layer is 200-1000 nm; the material forming the electron transport layer includes [6,6]-phenyl C 61 Methyl butyrate, [6,6]-phenyl C 71At least one of methyl butyrate, fullerene C60, fullerene C70, tin dioxide, and zinc oxide; the material forming the hole transport layer includes at least one of poly[bis(4-phenyl)(2,4,6-trimethylphenyl)amine], 2,2',7,7'-tetrakis[N,N-bis(4-methoxyphenyl)amino]-9,9'-spirobifluorene, poly-3-hexylthiophene, triphenylamine with triptycene as the core, 3,4-ethylenedioxythiophene-methoxytriphenylamine, N-(4-phenylamino)carbazole-spirobifluorene, poly(3,4-ethylenedioxythiophene), poly(styrenesulfone), polythiophene, nickel oxide, molybdenum oxide, cuprous iodide, and cuprous oxide; the material forming the back electrode layer includes at least one of Ag, Cu, C, Au, Al, ITO, AZO, BZO, and IZO. This can further improve the performance of perovskite solar cells.

[0014] The present invention also provides a method for preparing the aforementioned perovskite solar cell, comprising forming a resistance-reducing layer between the perovskite light-absorbing layer and the electron transport layer by evaporation. This method thus possesses all the features and advantages of the aforementioned perovskite solar cell, and will not be further elaborated here. In general, the perovskite solar cell device prepared by this method has a high fill factor and is also simple to operate.

[0015] According to an embodiment of the present invention, the evaporation rate is 0.005-0.03 A / s. Thus, a resistance-reducing layer with a dense structure can be obtained.

[0016] According to an embodiment of the present invention, after the evaporation is completed, the method further comprises the step of evacuating the chamber, wherein the evacuation time is 20-40 minutes. Thus, the obtained perovskite solar cell can have better performance.

[0017] According to an embodiment of the present invention, the method includes: providing a transparent electrode layer; forming an electron transport layer on one side of the transparent electrode layer; forming a resistance reduction layer on the side of the electron transport layer away from the transparent electrode layer; forming a perovskite light absorption layer on the side of the resistance reduction layer away from the electron transport layer; forming a hole transport layer on the side of the perovskite light absorption layer away from the resistance reduction layer; and forming a back electrode layer on the side of the hole transport layer away from the perovskite light absorption layer. In this way, a perovskite solar cell with a formal structure can be prepared.

[0018] According to an embodiment of the present invention, the method includes: providing a transparent electrode layer; forming a hole transport layer on one side of the transparent electrode layer; forming a perovskite light absorption layer on the side of the hole transport layer away from the transparent electrode layer; forming a resistance reduction layer on the side of the perovskite light absorption layer away from the hole transport layer; forming an electron transport layer on the side of the resistance reduction layer away from the perovskite light absorption layer; and forming a back electrode layer on the side of the electron transport layer away from the resistance reduction layer. In this way, a perovskite solar cell with an inverted structure can be prepared.

[0019] The present invention also provides an electrical device comprising the aforementioned perovskite solar cell. This device thus possesses all the features and advantages of the aforementioned perovskite solar cell, which are not further elaborated here. In summary, the perovskite solar cell in this device exhibits excellent performance. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] FIG1 is a schematic structural diagram of a perovskite solar cell according to one embodiment of the present invention;

[0021] FIG2 is a schematic structural diagram of a perovskite solar cell according to another embodiment of the present invention;

[0022] FIG3 is a schematic structural diagram of a perovskite solar cell according to another embodiment of the present invention;

[0023] Description of Reference Numerals

[0024] 100-perovskite light absorption layer, 200-resistance reduction layer, 300-electron transport layer, 400-hole transport layer, 500-transparent electrode layer, 600-back electrode layer. DETAILED DESCRIPTION

[0025] Below, the scheme of the present invention will be explained in conjunction with embodiment.It will be understood by those skilled in the art that the following examples are only used to illustrate the present invention and should not be regarded as limiting the scope of the present invention.In the embodiment, if specific technology or conditions are not indicated, the technology or conditions described in the literature in this area or the product instructions are used.The reagents or instruments used are not indicated by the manufacturer, and are all conventional products that can be obtained by commercial purchase.

[0026] The present invention provides a perovskite solar cell. Referring to FIG1 , the perovskite solar cell includes: a perovskite light absorbing layer 100, an electron transport layer 300, and a resistance reduction layer 200 located between the perovskite light absorbing layer 100 and the electron transport layer 300. Thus, the resistance reduction layer 200 can reduce the residual Schottky barrier at the interface between the perovskite light absorbing layer 100 and the electron transport layer 300, reduce the contact resistance between the perovskite light absorbing layer 100 and the electron transport layer 300, and improve the fill factor of the perovskite solar cell device. In addition, the resistance reduction layer 200 can also reduce interface defect states, reduce non-radiative recombination, and improve the efficiency and batch stability of the device.

[0027] For ease of understanding, the following briefly explains the principle by which the perovskite solar cell of the present application can achieve the above-mentioned beneficial effects:

[0028] As mentioned above, since the contact resistance between the various film layers of the battery affects the fill factor of the device, the performance of the battery cannot be fully improved and utilized. Although in the related art, this problem can be improved by preparing a passivation layer between the perovskite light-absorbing layer and the hole transport layer. To be specific, in the related art, a passivation layer is prepared on the perovskite after the preparation is completed by a solution method, so that the interface contact quality is increased, the interface contact is tighter, the defect state is reduced, and the efficiency and stability of the device are improved to a certain extent. However, this method still needs to be heated in the preparation process to obtain the passivation layer. During the heating process, part of the passivation layer material may be decomposed by heat. This method has the problem of poor repeatability, which makes the batch stability of the device poor. The present application inserts a layer of material as a resistance-reducing layer between the perovskite light-absorbing layer and the electron transport layer. With the help of evaporation equipment, the thickness and density of the sulfide can be accurately controlled, and the batch stability of the device can be further improved while passivating the interface defect state and reducing non-radiative recombination. The material used in the resistance-reduction layer can optimize the interface between the electron transport layer and the perovskite light-absorbing layer, increasing the interfacial contact area, reducing interface defects, lowering the residual Schottky barrier between the electron transport layer and the perovskite light-absorbing layer, reducing contact resistance, and improving carrier transport. Furthermore, the resistance-reduction layer of a certain thickness can be formed through methods including, but not limited to, vapor deposition, allowing for controlled thickness and improved device reproducibility.

[0029] According to an embodiment of the present invention, the material forming the resistance-reducing layer 200 includes at least one of a metal sulfide, a metalloid sulfide, and a sulfur-containing organic compound. As a result, the resistance-reducing layer 200 can effectively reduce the contact resistance between the perovskite light-absorbing layer 100 and the electron transport layer 300. Specifically, the sulfur in the resistance-reducing layer 200 can interact with the uncoordinated lead in the perovskite light-absorbing layer 100, forming a chemical bond between the sulfur and the lead, reducing interfacial defect states and lowering the contact resistance.

[0030] The metal sulfides include, but are not limited to, alkali metal sulfides, alkaline earth metal sulfides, and transition metal sulfides.

[0031] Metalloid sulfides are compounds formed by metalloids and sulfur. Metalloids have physical and chemical properties intermediate between those of metals and non-metals. Metalloids include boron, silicon, germanium, selenium, tellurium, polonium, arsenic, and antimony. Furthermore, metalloid sulfides include boron sulfide, silicon sulfide, germanium sulfide, selenium sulfide, tellurium sulfide, polonium sulfide, arsenic sulfide, and antimony sulfide.

[0032] Sulfur-containing organic compounds are organic compounds substituted with one, two, or more sulfur-containing functional groups. Specifically, sulfur-containing organic compounds are aliphatic hydrocarbon compounds or aromatic hydrocarbon compounds substituted with one, two, or more sulfhydryl groups (-SH) or sulfonic acid groups (-SO3H). For example, sulfur-containing compounds include, but are not limited to, butanesulfonic acid and benzenesulfonic acid.

[0033] According to an embodiment of the present invention, the material forming the resistance reduction layer 200 includes at least one of lithium sulfide, potassium sulfide, magnesium sulfide, arsenic sulfide, indium sulfide, manganese sulfide, and cobalt sulfide, thereby effectively improving the performance of the perovskite solar cell.

[0034] According to an embodiment of the present invention, the thickness of the resistance-reducing layer 200 is less than or equal to 3 nm. This effectively reduces the contact resistance between the perovskite light-absorbing layer 100 and the electron transport layer 300, effectively improving the fill factor of the perovskite solar cell device. If the thickness of the resistance-reducing layer 200 is too large, it will block the transmission of electrons and reduce the performance of the perovskite solar cell.

[0035] According to some embodiments of the present invention, the thickness of the resistance-reducing layer 200 may be 1 to 3 nm, specifically 1 nm, 1.5 nm, 2 nm, 2.5 nm, or 3 nm. The resistance-reducing layer 200 having a thickness within the above range can be easily formed by methods including, but not limited to, evaporation. It will not be too thin to form a continuous film layer, nor will it be too thick to block carrier transport at the interface, increase contact resistance, or reduce fill factor.

[0036] According to an embodiment of the present invention, the perovskite solar cell further includes a back electrode layer 600, a transparent electrode layer 500, and a hole transport layer 400. Thus, the performance of the perovskite solar cell can be further improved.

[0037] According to an embodiment of the present invention, referring to FIG2 , the transparent electrode layer 500 is located on the side of the electron transport layer 300 away from the resistance reduction layer 200 ; the hole transport layer 400 is located on the side of the perovskite light absorption layer 100 away from the resistance reduction layer 200 ; and the back electrode layer 600 is located on the side of the hole transport layer 400 away from the perovskite light absorption layer 100 . Thus, the structure of the perovskite solar cell is a stacked arrangement: transparent electrode layer 500, electron transport layer 300, resistance reduction layer 200, perovskite light absorption layer 100, hole transport layer 400, back electrode layer 600, that is, the perovskite solar cell of the present invention can have a formal device structure. For a formal perovskite solar cell, the introduction of the resistance reduction layer 200 can not only reduce the interfacial contact resistance, but also increase its bonding strength with the lead in the perovskite precursor solution, improve the perovskite crystallization quality, and enhance the device stability. Specifically, the perovskite precursor solution contains uncoordinated lead, which can interact with the sulfur in the resistance reduction layer 200 to form a chemical bond between the sulfur and the lead, thereby having a greater bonding strength between the resistance reduction layer 200 and the perovskite light absorbing layer 100.

[0038] According to other embodiments of the present invention, with reference to FIG3 , the hole transport layer 400 is located on the side of the perovskite light absorbing layer 100 away from the resistance reduction layer 200; the transparent electrode layer 500 is located on the side of the hole transport layer 400 away from the perovskite light absorbing layer 100; and the back electrode layer 600 is located on the side of the electron transport layer 300 away from the resistance reduction layer 200. Thus, the structure of the perovskite solar cell is stacked: the transparent electrode layer 500, the hole transport layer 400, the perovskite light absorbing layer 100, the resistance reduction layer 200, the electron transport layer 300, and the back electrode layer 600, that is, the perovskite solar cell of the present invention can have an inverted device structure. For an inverted perovskite solar cell, the resistance reduction layer 200 can not only reduce the interfacial contact resistance, but the resistance reduction layer 200 can also act as a protective layer for the electron transport layer 300, preventing the migrating ions from directly contacting the back electrode layer 600, causing unnecessary ion migration, etc.

[0039] According to an embodiment of the present invention, the material forming the transparent electrode layer 500 includes at least one of FTO, ITO, AZO, BZO, and IZO.

[0040] According to an embodiment of the present invention, the chemical formula of the material forming the perovskite light absorbing layer 100 is ABX3 or A2CDX6, wherein A is a methylamino group (CH3NH3 + ), carboxamidino (HC(NH2)2+ ), cesium ions (Cs + ), rubidium ions (Rb + ), B is a divalent lead ion (Pb 2+ ), divalent tin ions (Sn 2+ ), C is a monovalent silver ion (Ag + ), D is a trivalent bismuth ion (Bi 3+ ), X is a chloride ion (Cl - ), bromide ion (Br - ), iodide ion (I - ) at least one.

[0041] According to an embodiment of the present invention, the band gap of the perovskite light absorbing layer 100 is 1.20-2.30 eV, for example, 1.20 eV, 1.30 eV, 1.40 eV, 1.50 eV, 1.60 eV, 1.70 eV, 1.80 eV, 1.90 eV, 2.00 eV, 2.10 eV, 2.20 eV, or 2.30 eV.

[0042] According to an embodiment of the present invention, the thickness of the perovskite light absorbing layer 100 is 200-1000 nm, for example, 200 nm, 300 nm, 400 nm, 500 nm, 600 nm, 700 nm, 800 nm, 900 nm, or 1000 nm;

[0043] According to an embodiment of the present invention, the material forming the electron transport layer 300 includes [6,6]-phenyl C 61 Methyl butyrate (PC 61 BM), [6,6]-phenyl C 71 Methyl butyrate (PC 71 At least one of BM, fullerene C60 (C60), fullerene C70 (C70), tin dioxide (SnO2), and zinc oxide (ZnO). The materials forming the electron transport layer 300 are not limited to the above materials, but can also be derivatives of the above materials, or materials obtained by doping or passivation. These materials are electron transport layer materials that match the electronic energy levels of perovskite, ensuring electron transport while blocking hole migration. The sulfide insertion layer can reduce contact resistance and enhance carrier mobility.

[0044] According to an embodiment of the present invention, the material forming the hole transport layer 400 includes 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), triphenylamine with triptycene as the core (H101), 3,4-ethylenedioxythiophene-methoxytriphenylamine (EDOT-OMeTPA), N- (4-anilino) carbazole-spirobifluorene (CzPAF-SBF), poly (3,4-ethylenedioxythiophene), poly (styrene sulfonate) (PEDOT:PSS), polythiophene, nickel oxide (NiO x ), molybdenum oxide (MoO3), cuprous iodide (CuI), and cuprous oxide (CuO).

[0045] According to an embodiment of the present invention, the material forming the back electrode layer 600 includes at least one of Ag, Cu, C, Au, Al, ITO, AZO, BZO, and IZO.

[0046] The present invention also provides a method for preparing the aforementioned perovskite solar cell, the method comprising: forming a resistance reduction layer 200 between the perovskite light absorbing layer 100 and the electron transport layer 300 by evaporation. Thus, this method has all the features and advantages of the perovskite solar cell described above, and will not be repeated here. In general, the perovskite solar cell device prepared by this method has a high fill factor. In addition, this method has the advantage of simple operation.

[0047] Technicians can precisely control the thickness of the resistance-reducing layer 200 by adjusting the evaporation parameters, ensuring that the thickness of the resistance-reducing layer 200 is less than or equal to 3 nm. Specifically, the density of the resistance-reducing layer 200 can be controlled by adjusting the evaporation rate. During evaporation, the thickness of the resistance-reducing layer 200 can be monitored in real time using an instrument. When the resistance-reducing layer 200 reaches the specified thickness, evaporation is stopped.

[0048] In some specific embodiments of the present invention, the evaporation rate may be 0.005-0.03 A / s, for example 0.01 A / s. Thus, a resistance-reducing layer 200 having a dense structure may be obtained.

[0049] When forming the resistance-reducing layer 200 by evaporation, the initial 1 nm of evaporation is discarded because the rate is unstable at the beginning. Evaporation can be resumed after the rate stabilizes. Specifically, a shield can be placed at the beginning of evaporation. After 1 nm of evaporation has been completed, the shield can be opened. Once the desired thickness is reached, the shield can be replaced.

[0050] In some embodiments of the present invention, when forming the resistance-reducing layer 200, after the evaporation is completed, the method further includes a step of evacuating the chamber, after which subsequent operations are performed. This evacuation can remove residual substances within the chamber. The evacuation time can be 20-40 minutes, for example, 30 minutes. This can result in a perovskite solar cell with superior performance.

[0051] According to an embodiment of the present invention, the method includes: providing a transparent electrode layer 500; forming an electron transport layer 300 on one side of the transparent electrode layer 500; forming a resistance reduction layer 200 on a side of the electron transport layer 300 away from the transparent electrode layer 500; forming a perovskite light absorption layer 100 on a side of the resistance reduction layer 200 away from the electron transport layer 300; forming a hole transport layer 400 on a side of the perovskite light absorption layer 100 away from the resistance reduction layer 200; and forming a back electrode layer 600 on a side of the hole transport layer 400 away from the perovskite light absorption layer 100. Thus, a perovskite solar cell having a formal structure as shown in FIG. 2 can be prepared.

[0052] According to other embodiments of the present invention, the method includes: providing a transparent electrode layer 500; forming a hole transport layer 400 on one side of the transparent electrode layer 500; forming a perovskite light absorption layer 100 on a side of the hole transport layer 400 away from the transparent electrode layer 500; forming a resistance reduction layer 200 on a side of the perovskite light absorption layer 100 away from the hole transport layer 400; forming an electron transport layer 300 on a side of the resistance reduction layer 200 away from the perovskite light absorption layer 100; and forming a back electrode layer 600 on a side of the electron transport layer 300 away from the resistance reduction layer 200. Thus, a perovskite solar cell with an inverted structure as shown in FIG. 3 can be prepared.

[0053] The present invention also provides an electrical device comprising the aforementioned perovskite solar cell. This device thus possesses all the features and advantages of the aforementioned perovskite solar cell, which are not further elaborated here. In summary, the perovskite solar cell in this device exhibits excellent performance.

[0054] Specifically, perovskite solar cells can be used as a power source for electrical devices, such as, but not limited to, electric vehicles, battery-powered vehicles, electric toys, and electric tools.

[0055] In the examples described below in this application, unless otherwise stated, the reagents used can be purchased from the market or can be prepared by the methods described in this application.

[0056] Example 1

[0057] As shown in Figure 1, a perovskite solar cell using lithium sulfide as a modified layer has an inverted perovskite solar cell structure that is sequentially provided with a transparent electrode layer, a hole transport layer, a perovskite light absorption layer, a metal sulfide resistance reduction layer, an electron transport layer, and a back electrode layer.

[0058] 1) A 2.0*2.0cm ITO conductive glass was laser etched to remove 0.35cm of ITO from each end, exposing the glass substrate.

[0059] 2) Ultrasonic cleaning of the etched ITO conductive glass with water, acetone, and isopropyl alcohol several times in sequence;

[0060] 3) The ITO conductive glass was blown dry with a nitrogen gun to remove the solvent and then placed in a UV ozone machine for further cleaning;

[0061] 4) After spin coating a 2 mg / mL PTAA organic hole transport layer on the UV-ozone treated ITO substrate at a rate of 5000 rpm / s, the organic hole transport layer was annealed on a hot plate at 100°C for 10 minutes;

[0062] 5) Spin-coat the prepared hole transport layer with a perovskite precursor solution at 1000-5000 rpm / s, anneal at 100°C for 30 min, and cool to room temperature. The active material of the perovskite light absorbing layer is FA. 0.83 Cs 0.17 PbI3.

[0063] 6) Place the obtained sheet into the vapor deposition machine and wait for the vacuum degree of vapor deposition to reach 5*10 -4 Below Pa, 1 nm lithium sulfide was evaporated at a rate of 0.02 A / s, followed by 30 nm electron transport layer C60 at a rate of 0.05 A / s, and finally 80 nm back electrode layer Cu was evaporated at a rate of 0.1 A / s;

[0064] 7) The perovskite solar cell obtained in the above steps is marked as cell 1.

[0065] Example 2

[0066] Except for step 6), the other steps are the same as those in Example 1.

[0067] 6) Evaporate 2nm thick lithium sulfide at a rate of 0.02A / s, then evaporate 30nm electron transport layer C60 at a rate of 0.05A / s, and finally evaporate 80nm back electrode layer Cu at a rate of 0.1A / s;

[0068] The perovskite solar cell obtained in this example is labeled as Cell 2.

[0069] Example 3

[0070] Except step 6), the other steps are the same as those in Example 1.

[0071] 6) Place the obtained sheet into the vapor deposition machine and wait for the vacuum degree of vapor deposition to reach 5*10 -4 Below Pa, 3nm lithium sulfide was evaporated at a rate of 0.02A / s, followed by 30nm electron transport layer C60 at a rate of 0.05A / s, and finally 80nm back electrode layer Cu was evaporated at a rate of 0.1A / s;

[0072] The perovskite solar cell obtained in this example is labeled as cell 3.

[0073] Example 4

[0074] Except step 6), the other steps are the same as those in Example 1.

[0075] 6) Place the obtained sheet into the vapor deposition machine and wait for the vacuum degree of vapor deposition to reach 5*10 -4 Below Pa, 1 nm potassium sulfide was evaporated at a rate of 0.02 A / s, followed by 30 nm electron transport layer C60 at a rate of 0.05 A / s, and finally 80 nm back electrode layer Cu was evaporated at a rate of 0.1 A / s;

[0076] The perovskite solar cell obtained in this example is labeled as cell 4.

[0077] Example 5

[0078] Except step 6), the other steps are the same as those in Example 1.

[0079] 6) Vapor-deposit 1 nm thick magnesium sulfide at a rate of 0.02 A / s, then vapor-deposit a 30 nm electron transport layer C60 at a rate of 0.05 A / s, and finally vapor-deposit an 80 nm back electrode layer Cu at a rate of 0.1 A / s;

[0080] The perovskite solar cell obtained in this example is labeled as cell 5.

[0081] Example 6

[0082] Except step 6), the other steps are the same as those in Example 1.

[0083] 6) Evaporate 1 nm thick arsenic sulfide at a rate of 0.02 A / s, then evaporate 30 nm of electron transport layer C60 at a rate of 0.05 A / s, and finally evaporate 80 nm of back electrode layer Cu at a rate of 0.1 A / s;

[0084] The perovskite solar cell obtained in this example is labeled as cell 6.

[0085] Example 7

[0086] Except step 6), the other steps are the same as those in Example 1.

[0087] 6) Evaporate 1 nm thick indium sulfide at a rate of 0.02 A / s, then evaporate 30 nm of electron transport layer C60 at a rate of 0.05 A / s, and finally evaporate 80 nm of back electrode layer Cu at a rate of 0.1 A / s;

[0088] The perovskite solar cell obtained in this example is labeled as cell 7.

[0089] Example 8

[0090] Except step 6), the other steps are the same as those in Example 1.

[0091] 6) Evaporate 1 nm thick manganese sulfide at a rate of 0.02 A / s, then evaporate 30 nm of electron transport layer C60 at a rate of 0.05 A / s, and finally evaporate 80 nm of back electrode layer Cu at a rate of 0.1 A / s;

[0092] The perovskite solar cell obtained in this example is labeled as cell 8.

[0093] Example 9

[0094] Except step 6), the other steps are the same as those in Example 1.

[0095] 6) Evaporate 1 nm thick cobalt sulfide at a rate of 0.02 A / s, then evaporate 30 nm of electron transport layer C60 at a rate of 0.05 A / s, and finally evaporate 80 nm of back electrode layer Cu at a rate of 0.1 A / s;

[0096] The perovskite solar cell obtained in this example is labeled as cell 9.

[0097] Example 10

[0098] Except step 6), the other steps are the same as those in Example 1.

[0099] 6) Spin-coat an organic passivation layer (PCBM, 1 mg / ml, solvent chlorobenzene, acceleration speed 5000 rpm / s, spin coating time 30 s, annealing at 100 °C for 10 min) on the prepared perovskite film, and place the obtained wafer into the vapor deposition machine until the vacuum degree of the vapor deposition reaches 5*10 -4 Below Pa, evaporate 30nm electron transport layer C60 at a rate of 0.05A / s, and finally evaporate 80nm back electrode layer Cu at a rate of 0.1A / s;

[0100] The perovskite solar cell obtained in this example is labeled as cell 10 .

[0101] Example 11

[0102] Except step 6), the other steps are the same as those in Example 1.

[0103] 6) Place the obtained sheet into the vapor deposition machine and wait for the vacuum degree of vapor deposition to reach 5*10 -4 Below Pa, first evaporate lithium fluoride with a thickness of 1 nm at a rate of 0.02 A / s, then evaporate 30 nm of electron transport layer C60 at a rate of 0.05 A / s, and finally evaporate 80 nm of back electrode layer Cu at a rate of 0.1 A / s;

[0104] The perovskite solar cell obtained in this example is labeled as cell 11.

[0105] Comparative Example 1

[0106] 1) A 2.0*2.0cm ITO conductive glass was laser etched to remove 0.35cm of ITO from each end, exposing the glass substrate.

[0107] 2) Ultrasonic cleaning of the etched ITO conductive glass with water, acetone, and isopropyl alcohol several times in sequence;

[0108] 3) The ITO conductive glass was blown dry with a nitrogen gun to remove the solvent and then placed in a UV ozone machine for further cleaning;

[0109] 4) After spin coating a 2 mg / mL PTAA organic hole transport layer on the UV-ozone treated ITO substrate at a rate of 5000 rpm / s, the organic hole transport layer was annealed on a hot plate at 100°C for 10 minutes;

[0110] 5) Spin-coat the prepared hole transport layer with a perovskite precursor solution at 1000-5000 rpm / s, anneal at 100°C for 30 min, and cool to room temperature. The active material of the perovskite light absorbing layer is FA. 0.83 Cs 0.17 PbI3.

[0111] 6) Place the obtained sheet into the vapor deposition machine and wait for the vacuum degree of vapor deposition to reach 5*10 -4 Below Pa, evaporate 30nm electron transport layer C60 at a rate of 0.05A / s, and finally evaporate 80nm back electrode layer Cu at a rate of 0.1A / s;

[0112] 7) The perovskite solar cell obtained in the above steps is marked as cell 12.

[0113] Test Method

[0114] 1. Contact resistance of perovskite solar cells

[0115] Under standard simulated sunlight (AM 1.5G, 100mW / cm 2 ) irradiation, the battery performance is tested, the IV curve is obtained, and the computer automatically reads the contact resistance value based on the data.

[0116] 2. Photovoltaic conversion efficiency of perovskite solar cells

[0117] Under standard simulated sunlight (AM 1.5G, 100mW / cm 2 ) irradiation, the battery performance is tested and the IV curve is obtained. According to the IV curve and the data fed back by the test equipment, the short-circuit current Jsc (unit: mA / cm 2 ), open-circuit voltage Voc (V), maximum optical output current Jmpp (mA), and maximum optical output voltage Vmpp (V). The cell's fill factor (FF) (in %) is calculated using the formula FF = Jsc × Voc / (Jmpp × Vmpp). The cell's photoelectric conversion efficiency (PCE) (in %) is calculated using the formula PCE = Jsc × Voc × FF / Pw, where Pw represents the input power (in mW).

[0118] The perovskite solar cells obtained in the above embodiment and comparative example were tested according to the above process. The specific values ​​are shown in Table 1.

[0119] Table 1 Effects of different resistance reduction layer materials on device performance

[0120]

[0121] As can be seen from Table 1, the contact resistance of Example 1-11 is less than the contact resistance of Comparative Example 1, indicating that after a resistance reduction layer is provided between the perovskite light absorbing layer and the electron transport layer, the contact resistance can be reduced, the fill factor of the perovskite solar cell device can be improved, and the perovskite solar cell can be made to have more excellent performance. Moreover, the comprehensive performance of the battery of Example 1-9 is better than the comprehensive performance of the battery of Example 10-11, that is, compared with PCBM and lithium fluoride as the resistance reduction layer material, sulfide is used as the resistance reduction layer material, which can make the perovskite solar cell have more excellent performance. Moreover, in Example 1-9, the battery of Example 1-5 and Example 7 has more excellent comprehensive performance, that is, the material forming the resistance reduction layer is preferably lithium sulfide, potassium sulfide, magnesium sulfide, indium sulfide, and the contact resistance of the prepared perovskite solar cell is lower at this time, and the perovskite solar cell has more excellent comprehensive performance.

[0122] The embodiments of the present invention have been described in detail above. However, the present invention is not limited to the specific details of the above embodiments. Within the technical concept of the present invention, various simple variations of the technical solution of the present invention can be made, and these simple variations all fall within the scope of protection of the present invention. It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any appropriate manner without contradiction.

[0123] It should be noted that, in the description of this specification, the reference terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" mean that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic expressions 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 any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art can combine and combine different embodiments or examples described in this specification and the features of different embodiments or examples, unless they are contradictory.

[0124] Although the embodiments of the present invention have been shown and described above, it will be understood that the above embodiments are illustrative and are not to be construed as limitations on the present invention. A person skilled in the art may change, modify, replace and modify the above embodiments within the scope of the present invention.

Claims

1. A perovskite solar cell, It is characterized in that The perovskite solar cell comprises: a perovskite light absorbing layer, an electron transport layer, and a resistance reducing layer located between the perovskite light absorbing layer and the electron transport layer.

2. The perovskite solar cell according to claim 1, It is characterized in that The material forming the resistance reduction layer includes at least one of metal sulfide, metalloid sulfide and sulfur-containing organic matter.

3. The perovskite solar cell according to claim 2, It is characterized in that The material forming the resistance reduction layer includes at least one of lithium sulfide, potassium sulfide, magnesium sulfide, arsenic sulfide, indium sulfide, manganese sulfide, and cobalt sulfide.

4. The perovskite solar cell according to claim 1, It is characterized in that The thickness of the resistance reduction layer is less than or equal to 3 nm.

5. The perovskite solar cell according to claim 4, It is characterized in that The thickness of the resistance reduction layer is 1-3 nm.

6. The perovskite solar cell according to claim 1, It is characterized in that The perovskite solar cell also includes a back electrode layer, a transparent electrode layer and a hole transport layer; The structure of the perovskite solar cell satisfies any one of the following conditions: The transparent electrode layer is located on a side of the electron transport layer away from the resistance reduction layer; the hole transport layer is located on a side of the perovskite light absorption layer away from the resistance reduction layer; and the back electrode layer is located on a side of the hole transport layer away from the perovskite light absorption layer; The hole transport layer is located on a side of the perovskite light absorption layer away from the resistance reduction layer; the transparent electrode layer is located on a side of the hole transport layer away from the perovskite light absorption layer; and the back electrode layer is located on a side of the electron transport layer away from the resistance reduction layer.

7. The perovskite solar cell according to claim 6, It is characterized in that The material forming the transparent electrode layer includes at least one of FTO, ITO, AZO, BZO, and IZO.

8. The perovskite solar cell according to claim 6, It is characterized in that The chemical formula of the material forming the perovskite light absorbing layer is ABX 3 or A 2 CDX 6 , wherein A is at least one of methylamine, methylamidine, cesium, and rubidium ions, B is at least one of divalent lead ions and divalent tin ions, C is a monovalent silver ion, D is a trivalent bismuth ion, and X is at least one of chloride, bromide, and iodide ions.

9. The perovskite solar cell according to claim 6, It is characterized in that The band gap of the perovskite light absorbing layer is 1.20-2.30 eV.

10. The perovskite solar cell according to claim 6, It is characterized in that The thickness of the perovskite light-absorbing layer is 200-1000nm.

11. The perovskite solar cell according to claim 6, It is characterized in that The material forming the electron transport layer includes [6,6]-phenyl C 61 Methyl butyrate, [6,6]-phenyl C 71 At least one of methyl butyrate, fullerene C60, fullerene C70, tin dioxide, and zinc oxide.

12. The perovskite solar cell according to claim 6, It is characterized in that The material forming the hole transport layer includes at least one of poly[bis(4-phenyl)(2,4,6-trimethylphenyl)amine], 2,2',7,7'-tetrakis[N,N-di(4-methoxyphenyl)amino]-9,9'-spirobifluorene, poly-3-hexylthiophene, triphenylamine with triptycene as the core, 3,4-ethylenedioxythiophene-methoxytriphenylamine, N-(4-aniline)carbazole-spirobifluorene, poly(3,4-ethylenedioxythiophene), poly(styrene sulfone), polythiophene, nickel oxide, molybdenum oxide, cuprous iodide, and cuprous oxide.

13. The perovskite solar cell according to claim 6, It is characterized in that The material forming the back electrode layer includes at least one of Ag, Cu, C, Au, Al, ITO, AZO, BZO, and IZO.

14. A method for preparing the perovskite solar cell according to any one of claims 1 to 13, It is characterized in that The method comprises: forming a resistance-reducing layer between a perovskite light-absorbing layer and an electron transport layer by evaporation.

15. The method according to claim 14, It is characterized in that The evaporation rate is 0.005-0.03 A / s.

16. The method according to claim 14, It is characterized in that After the evaporation is completed, the method further comprises the step of evacuating the chamber, and the evacuation time is 20-40 minutes.

17. The method according to claim 14, It is characterized in that The method comprises: providing a transparent electrode layer; forming an electron transport layer on one side of the transparent electrode layer; forming a resistance reduction layer on a side of the electron transport layer away from the transparent electrode layer; forming a perovskite light absorbing layer on a side of the resistance reduction layer away from the electron transport layer; forming a hole transport layer on a side of the perovskite light absorbing layer away from the resistance reducing layer; A back electrode layer is formed on a side of the hole transport layer away from the perovskite light absorbing layer.

18. The method according to claim 14, It is characterized in that The method comprises: providing a transparent electrode layer; forming a hole transport layer on one side of the transparent electrode layer; forming a perovskite light absorbing layer on a side of the hole transport layer away from the transparent electrode layer; forming a resistance reduction layer on a side of the perovskite light absorbing layer away from the hole transport layer; forming an electron transport layer on a side of the resistance reduction layer away from the perovskite light absorbing layer; A back electrode layer is formed on a side of the electron transport layer away from the resistance reduction layer.

19. An electrical device, It is characterized in that The electrical device comprises the perovskite solar cell according to any one of claims 1 to 13.

Images