Preparation method for perovskite solar cell, solar cell and photovoltaic system

Abstract

Disclosed are a method for preparing a perovskite solar cell, a solar cell, and a photovoltaic system. In the method for preparing a perovskite solar cell provided by the present invention, a passivation gas is introduced into the etching region during the process of laser etching of a second etched groove and a third etched groove. The passivation gas reacts with Pb2+ in the perovskite layer to form a passivation film covering the etching position of the etched groove. During laser etching, the passivating gas is introduced to form the passivating film covering the etched portion, thus preventing the perovskite material from being exposed to a water and oxygen environment. This accelerates the aging process of the material, thereby reducing the service life and the photoelectric conversion capability of the perovskite module.

Description

Preparation method of perovskite solar cell, solar cell and photovoltaic system TECHNICAL FIELD

[0001] The present application relates to the field of solar cells, in particular to a preparation method of perovskite solar cell, solar cell and photovoltaic system. BACKGROUND

[0002] With the rapid development of renewable energy technology, perovskite solar cells as a new emerging photovoltaic technology. Perovskite solar cells include substrate, transparent conductive film, hole transport layer, perovskite layer, electron transport layer and metal electrode layer, in the process of manufacturing perovskite solar cells, laser etching technology as a kind of high precision, high efficiency processing means, is widely used in the optimization and fine processing of perovskite battery structure, laser etching utilizes the thermal effect or photochemical reaction generated by laser to realize the accurate removal of materials and form the required structure. However, in the process of laser etching, the precise removal of unnecessary materials will also cause the perovskite layer to be exposed to the outside, which will cause the perovskite material to be exposed to water and oxygen environment, thereby accelerating the aging process of the material and reducing the service life of the perovskite assembly and its photoelectric conversion ability. SUMMARY

[0003] The present application proposes a preparation method of perovskite solar cell, solar cell and photovoltaic system to solve the technical problem of perovskite solar cell in the process of laser etching, perovskite layer exposed to water and oxygen environment accelerating aging.

[0004] The technical scheme adopted by the present application is:

[0005] The present application proposes a preparation method of perovskite solar cell, which comprises the following steps:

[0006] Depositing a transparent conductive film layer on the substrate;

[0007] Cutting a first etching groove on the transparent conductive film layer by laser;

[0008] Depositing a hole transport layer on the transparent conductive film layer and in the first etching groove;

[0009] Preparing a perovskite layer on the hole transport layer;

[0010] Preparing an electron transport layer on the perovskite layer;

[0011] Forming a second etching groove through the hole transport layer, perovskite layer and electron transport layer by laser etching, and introducing a passivation gas into the etching site during the etching process, so that the passivation gas and the perovskite layer in the perovskite layer react with each other to form a passivation film covering the second etching groove etching site; ​

[0012] depositing a metal electrode on the electron transport layer and in the second etching groove;

[0013] forming a third etching groove through the hole transport layer, the perovskite layer, the electron transport layer and the metal electrode by laser etching, and introducing a passivation gas into the etching groove during the etching process, so that the passivation gas and the perovskite layer in the etching groove react with each other to form a passivation film covering the etching groove.

[0014] Further, the passivation film is , and the corresponding passivation gas is or CS or SOx.

[0015] Further, the passivation film is , and the corresponding passivation gas is gaseous Al and oxygen.

[0016] Further, the passivation film is , and the corresponding passivation gas is a silicon source and nitrogen.

[0017] Further, the passivation film is AlN, and the corresponding passivation gas is a gaseous aluminum source and nitrogen.

[0018] Further, the flow rate of the passivation gas is between 50 and 75 seem.

[0019] Further, the passivation gas is continuously introduced into the etching groove for a first predetermined time during the laser etching process.

[0020] Further, the thickness of the passivation film is 10-50 nm.

[0021] The present application provides a solar cell, and a preparation method of the perovskite solar cell.

[0022] The present application provides a photovoltaic system, and the solar cell.

[0023] Compared with the prior art, the present application provides a preparation method of a perovskite solar cell, which introduces a passivation gas into the etching groove during the laser etching of a second etching groove and a third etching groove, so that the passivation gas and the perovskite layer in the etching groove react to form a passivation film covering the etching groove. The passivation gas is introduced during the laser etching process to form a passivation film covering the etching groove, which prevents the perovskite material from being exposed to a water and oxygen environment, thereby accelerating the aging process of the material and reducing the service life of the perovskite assembly and its photoelectric conversion capability. BRIEF DESCRIPTION OF DRAWINGS

[0024] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings needed to be used in the embodiments or prior art description will be briefly introduced as follows. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can also be obtained by those skilled in the art without any creative effort.

[0025] Fig. 1 is a schematic diagram of the structure of the first laser etched groove and the second laser etched groove according to an embodiment of the present application;

[0026] Fig. 2 is a schematic diagram of the structure of the first laser etched groove, the second laser etched groove and the third laser etched groove according to an embodiment of the present application;

[0027] Fig. 3 is a flow chart of the preparation method of the perovskite solar cell according to an embodiment of the present application. DETAILED DESCRIPTION

[0028] In order to make the technical problems to be solved by the present application, the technical solutions and the beneficial effects more clearly understood, the present application will be further described in detail below with reference to the drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and not to limit the present application.

[0029] The principles and structures of the present application will be described in detail below with reference to the drawings and embodiments.

[0030] With the rapid development of renewable energy technology, perovskite solar cells are a new emerging photovoltaic technology. Perovskite solar cells include a substrate, a transparent conductive film, a hole transport layer, a perovskite layer, an electron transport layer and a metal electrode layer. In the manufacturing process of perovskite solar cells, laser etching technology is widely used in the optimization and fine processing of perovskite battery structure as a high-precision and high-efficiency processing means. Laser etching uses the thermal effect or photochemical reaction generated by laser to realize the precise removal of materials and form the required structure. However, in the laser etching process, the precise removal of unnecessary materials will also cause the perovskite layer to be exposed to the outside, which will cause the perovskite material to be exposed to the water and oxygen environment, thereby accelerating the aging process of the material and reducing the service life of the perovskite assembly and its photoelectric conversion capability.

[0031] As shown in Figs. 1-3, the present application proposes a preparation method of a perovskite solar cell, comprising the steps of:

[0032] depositing a transparent conductive film layer on the substrate;

[0033] cutting a first etched groove on the transparent conductive film layer by laser;

[0034] depositing a hole transport layer on the transparent conductive film layer and in the first etched groove;

[0035] a perovskite layer is prepared on the hole transport layer;

[0036] an electron transport layer is prepared on the perovskite layer;

[0037] a second etching groove is formed through the hole transport layer, the perovskite layer and the electron transport layer by laser etching, and a passivation gas is introduced into the etching groove during the laser etching, and the passivation gas and the perovskite layer react to form a passivation film covering the etching groove of the second etching groove;

[0038] a metal electrode is deposited on the electron transport layer and in the second etching groove, a third etching groove is formed through the hole transport layer, the perovskite layer, the electron transport layer and the metal electrode by laser etching, and a passivation gas is introduced into the etching groove during the laser etching, and the passivation gas and the perovskite layer react to form a passivation film covering the etching groove of the third etching groove.

[0039] The passivation film can prevent the key materials such as the perovskite layer from being damaged in the subsequent process or use process, and prolong the service life of the battery.

[0040] The substrate is glass or a silicon wafer, the solar cell is a perovskite solar cell, the perovskite solar cell is divided into a single-junction perovskite solar cell and a stacked perovskite solar cell, the substrate of the single-junction perovskite solar cell is glass, and the substrate of the stacked perovskite solar cell is a silicon wafer.

[0041] The passivation film is or or or AlN, and can also be other materials that are not easy to react.

[0042] When the passivation film is , the corresponding passivation gas is or CS or SOx.

[0043] When the passivation film is , the corresponding passivation gas is gaseous Al and oxygen.

[0044] When the passivation film is , the corresponding passivation gas is a silicon source and nitrogen.

[0045] When the passivation film is AlN, the corresponding passivation gas is a gaseous aluminum source and nitrogen.

[0046] ​​The passivation gas is continuously introduced to the etching position for a first preset time duration in the laser etching process, and the flow rate of the passivation gas is between 50-75sccm. The first preset time duration is 30s. The flow rate of the passivation gas and the first preset time duration of introducing the passivation gas can be changed according to actual conditions.

[0047] Specifically, in the laser etching process, the etching area is rapidly heated due to the laser effect, causing the perovskite layer to melt to achieve rapid removal of the material to form an etching groove. At this time, the gas is introduced into the laser etching groove at the same time, which can chemically react with lead ions in the perovskite layer to generate a lead-rich passivation film at the edge of the etching line. The key reaction equation of this process is as follows:

[0048]

[0049] Under normal temperature and pressure, The reaction process of the gas and the lead ion is slow and cannot achieve effective passivation, therefore, the laser effect process has extremely high power density and high coherence, which is an effective induction means.

[0050] Under normal temperature and pressure, the gas laser induction can form a 10nm-50nm thick passivation film; specifically, under normal temperature and pressure, the gas is introduced for 10min, and no obvious passivation film is observed to be formed, and loose large particles passivation film are generated after 30min; however, under laser induction, a 20nm thick passivation film can be formed within 30s.

[0051] The perovskite layer in the present application can include: lead iodide, stannous iodide, methyl iodide, and methylamine iodine; the perovskite layer is generally coated on the hole transport layer or the electron transport layer by coating.

[0052] The main effects of the laser include the following two aspects:

[0053] 1. Provide heat energy: the heat energy provided by the laser drives the occurrence of chemical reactions. At the same time, due to the small etching size (several tens of microns) and short molecular diffusion distance, efficient heat and mass transfer can be achieved, thereby accelerating the reaction process.

[0054] 2. Excite molecular state: photons collide with and lead iodide molecules to reach the excited state, accelerate the breaking and recombination process of molecular chemical bonds, and promote the rapid formation of lead sulfide film. The laser directly acts on the perovskite film with extremely high power density, causing the Pb-I bond to break in a very short time, releasing free Ions. These ions then react with the gas, almost instantaneously forming a dense passivation film, achieving efficient protection of the perovskite edge.

[0055] The passivation film formed under different gas flow rates was tested respectively. The test results show that, under the same time, as the gas flow rate increases, the thickness of the passivation film formed increases, and when the passivation gas flow rate exceeds 75 sccm, as the gas flow rate increases, the passivation film thickness remains unchanged. In summary, the passivation gas flow rate is between 50 and 75 sccm.

[0056] The passivation film has beneficial effects: on the one hand, the bond energy of Pb-S is greater than that of Pb-I, and at the interface, strongly bonded, effectively inhibiting I- migration; on the other hand, the hydrophobic properties of can effectively isolate the air from water vapor erosion, effectively improving the stability of the device.

[0057] The following explains each layer of the single-junction perovskite solar cell:

[0058] Substrate: The substrate of the single-junction perovskite solar cell is glass, which transmits sunlight into the cell.

[0059] Metal electrode: A metal or conductive material with metallic properties, such as gold, silver, copper, carbon, etc., is selected for the metal electrode, which is deposited by thermal evaporation.

[0060] Transparent conductive film layer: Commercial ITO or FTO is generally used for the transparent conductive film layer. It has a high transmittance of 80-90% in the visible light band, strong conductivity, and a suitable work function. These excellent properties enable the transparent electrode to have excellent charge horizontal and vertical transmission capabilities while ensuring high transmittance, which is beneficial for charge collection.

[0061] Perovskite layer: The core layer of the cell. It is used to absorb light energy to generate electron-hole pairs. The basic material is a perovskite precursor solution, which is composed of alkali metal halide perovskite and organic metal halide perovskite. Generally, organic-inorganic hybrid crystalline materials, such as organic metal trihalide (X = Cl\ Br\ I) are used as light absorbing materials, among which the most common is (methylamine lead iodide).

[0062] Hole transport layer: used to receive the holes transported by the perovskite layer and transport them into the electrode, while preventing the transport of electrons. The hole transport layer needs to have a good heterojunction contact interface with the perovskite layer, reduce the potential barrier in the process of hole transport, complete the hole transport while preventing the movement of electrons to the anode, and plays an important role in improving the photoelectric conversion efficiency of the solar cell. Commonly used materials include organic small molecules, organic polymers, and inorganic materials. The hole transport layer used in the p-i-n structure is mainly organic polymer PTAA, PEDOT:PSS (which can be solution-formed film, suitable for flexible substrate); the hole transport layer used in the n-i-p structure is mainly organic small molecules and inorganic materials: Spiro-OMeTAD, NiO, CuSCN, CuO, CuI, P3HT (poly-3-hexylthiophene) and the like.

[0063] Electron transport layer: the electron transport layer is used to receive the electrons transported by the perovskite layer and transport them into the electrode, while preventing the transport of holes. The electron transport layer must have a good contact with the perovskite layer, so that the potential barrier in the process of electron transport is reduced, and the transport of holes to the cathode is prevented while completing the electron transport, which plays an important role in improving the photoelectric conversion efficiency of the cell.

[0064] The present application also proposes a solar cell prepared by the solar cell preparation method.

[0065] The present application also proposes a photovoltaic system using the solar cell of the present application.

[0066] Compared with the prior art, the present application proposes a preparation method of a perovskite solar cell, which introduces a passivation gas into the etched part during the laser etching of the second etched groove and the third etched groove, and the passivation gas reacts with the perovskite layer in the etched groove to form a passivation film covering the etched part of the etched groove. The passivation gas is introduced during the laser etching process to form a passivation film covering the etched part, preventing the perovskite material from being exposed to a water and oxygen environment, thereby accelerating the aging process of the material and reducing the service life of the perovskite assembly and its photoelectric conversion capability.

[0067] It should be noted that the terms used above are only for the purpose of describing specific embodiments and are not intended to limit the exemplary embodiments according to the present application. As used herein, the singular form is intended to include the plural form, unless the context clearly indicates otherwise, and furthermore, it should be understood that when the terms "comprise" and / or "include" are used in the specification, there is a presence of the features, steps, operations, devices, components and / or combinations thereof.

[0068] In addition, it should be noted that the use of "first", "second", and the like words to qualify parts is merely for the convenience of distinguishing the corresponding parts, and the above words have no special meaning unless otherwise stated, and therefore cannot be understood as limiting the scope of protection of the present application.

[0069] The above only describes the preferred embodiments of the present application and is not intended to limit the present application. Various modifications and changes can be made by those skilled in the art based on the spirit and principles of the present application. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present application shall be included in the scope of protection of the present application.

Claims

1. A method for preparing a perovskite solar cell, characterized by, The method comprises the steps of: depositing a transparent conductive film layer on a substrate; cutting a first etching groove on the transparent conductive film layer by laser; depositing a hole transport layer on the transparent conductive film layer and in the first etching groove; preparing a perovskite layer on the hole transport layer; preparing an electron transport layer on the perovskite layer; A second etching groove is formed through the hole transport layer, the perovskite layer and the electron transport layer by laser etching, and a passivation gas is introduced to the etching site during the etching process, so that the passivation gas reacts with the perovskite layer in the etching site to form a passivation layer in the etching site. reacting with each other to form a passivation film covering the etching of the second etching groove; depositing a metal electrode on the electron transport layer and in the second etching groove; A third etching groove is formed through the hole transport layer, the perovskite layer, the electron transport layer and the metal electrode by laser etching, and a passivation gas is introduced to the etching site during the etching process, so that the passivation gas reacts with the perovskite layer in the etching site to form a passivation layer. reacting with each other to form a passivation film covering the etching of the third etching groove.

2. The method for preparing a perovskite solar cell as described in claim 1, characterized in that, The passivation film is , the corresponding passivation gas is or CS or SOx.

3. The method for preparing a perovskite solar cell as described in claim 1, characterized in that, The passivation film is corresponding to the passivation gas is gaseous Al and oxygen.

4. The method for preparing a perovskite solar cell as described in claim 1, characterized in that, The passivation film is , and the passivation gas is a silicon source and nitrogen.

5. The method for preparing a perovskite solar cell as described in claim 1, characterized in that, The passivation film is AlN, and the passivation gas is gaseous aluminum source and nitrogen.

6. The method of claim 2-5, wherein the perovskite solar cell is prepared by the steps of: The flow rate of the passivation gas is between 50 and 75 sccm.

7. The method for preparing a perovskite solar cell as described in claim 6, characterized in that, The passivation gas is continuously supplied to the etching for a first preset time during the laser etching process.

8. The method for preparing a perovskite solar cell as described in claim 7, characterized in that, The thickness of the passivation film is between 10 nm and 50 nm.

9. A solar cell, characterized by, The perovskite solar cell prepared by the method of any one of claims 1-8.

10. A photovoltaic system characterized by, The solar cell of claim 9.

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