Application of Carbohydrate Materials in Encapsulating Perovskite Solar Cells and Encapsulation Method

Abstract

The present invention discloses an application of a saccharide material in encapsulating a perovskite solar cell and an encapsulation method. The molten saccharide material is uniformly coated on one side of an encapsulation cover plate, and then the side of the encapsulation cover plate with the saccharide material is covered onto the top electrode of a pre-prepared perovskite solar cell, and cooling and solidification complete the encapsulation. The present invention applies the saccharide material to encapsulate the perovskite solar cell, which has a short time from the molten state to the solid state, a fast encapsulation speed, and does not require additional pressurization. The molten saccharide material can quickly and efficiently remove the air between the perovskite solar cell and the cover plate material by using the weight of the cover plate; the saccharide encapsulation material is green and environmentally friendly and inexpensive; the encapsulation process is simple, has high repeatability, has little influence on the intrinsic performance of the perovskite solar cell, and can significantly improve the light stability of the battery, having an industrial application prospect.

Description

Technical Field

[0001] The present invention belongs to the field of perovskite solar cells, and particularly relates to the application of a saccharide material in encapsulating a perovskite solar cell and an encapsulation method. Background Art

[0002] In recent years, perovskite solar cells based on perovskite-type metal halide light-absorbing materials have become a renewable energy technology that has attracted much attention. This new type of solar cell has the characteristics of high photoelectric conversion efficiency, low raw material cost, and easy production and preparation.

[0003] However, compared with semiconductor materials such as crystalline silicon in traditional solar cells, the perovskite material in perovskite solar cells still has certain stability problems. The most typical manifestation of the stability problem is that the perovskite material will decompose and be damaged in environments such as oxygen, moisture, and polar organic solvents. Therefore, through various encapsulation technologies, the materials inside the perovskite solar cell can be isolated from the external water, oxygen, and solvent environments to enhance the stability of the perovskite solar cell.

[0004] Currently, the more commonly used encapsulation technology is inherited from the field of crystalline silicon solar cells, that is, the perovskite solar cell, the polymer encapsulation film, and the encapsulation cover plate are stacked in sequence, and then the three are combined together by vacuum lamination technology (ACS Applied Materials & Interfaces, 2017, 9(30): 25073 - 25081). This vacuum lamination method has a high dependence on encapsulation equipment and is relatively complex to operate. 201910728362.5 discloses a method for encapsulating a perovskite solar cell using paraffin. The fluidity of paraffin at high temperature can effectively remove water and oxygen between the glass cover plate and the perovskite solar cell material.

[0005] However, during the operation of the perovskite solar cell, the temperature will rise, which may cause the polymer film or paraffin encapsulation material to soften, thereby affecting the stability. Therefore, how to improve the stability of the perovskite solar cell while encapsulating it is an urgent task. Summary of the Invention

[0006] The purpose of the present invention is to provide an application of a saccharide material in encapsulating a perovskite solar cell and an encapsulation method. The encapsulation material is green, environmentally friendly, and low in cost, and the encapsulation process is simple, with high repeatability, has little impact on the intrinsic stability of the device, and can significantly improve the light stability of the battery, having industrial application prospects.

[0007] Provide an application of a saccharide material in encapsulating a perovskite solar cell.

[0008] According to the above solution, the saccharide material is a solid saccharide compound that melts at 100-200 °C and solidifies after cooling.

[0009] According to the above solution, the saccharide material is a monosaccharide, disaccharide or sugar alcohol; preferably rock sugar or isomaltose.

[0010] According to the above solution, the specific application is as follows: uniformly coat the molten saccharide material on one side of the encapsulation cover plate, and then cover the side of the encapsulation cover plate with the saccharide material onto the top electrode of the pre-prepared perovskite solar cell, and cooling and solidifying to complete the encapsulation.

[0011] According to the above solution, the perovskite solar cell basically includes a transparent conductive substrate, an electron transport layer, a perovskite light absorption layer, a hole transport layer and a top electrode layer.

[0012] Provide a saccharide material encapsulation method for a perovskite solar cell, including the following steps:

[0013] Step 1. Heat up the saccharide material to melt it to form a molten state with fluidity;

[0014] Step 2. Uniformly coat the molten saccharide material on one side of an appropriately sized encapsulation cover plate to form an encapsulation layer;

[0015] Step 3. Cover the encapsulation layer onto the pre-prepared perovskite solar cell, with the side having the molten saccharide material in contact with the top electrode side of the perovskite solar cell;

[0016] Step 4. Wait for the molten saccharide material to cool into a solid to complete the encapsulation.

[0017] According to the above solution, the thickness of the encapsulation layer is 0.5-2 mm.

[0018] According to the above solution, the encapsulation cover plate is an airtight material. Preferably glass or ceramic.

[0019] According to the above solution, in step 3, hold one side of the encapsulation cover plate with tweezers, with the side covered with the molten saccharide material facing down, and the opposite side first contacts one side of the top electrode surface of the perovskite solar cell, and then lower the height of the other side of the encapsulation cover plate to make it cover the whole.

[0020] The present invention has the following beneficial effects:

[0021] 1. The present invention applies sugar materials to the encapsulation of perovskite solar cells. Sugar material molecules have a polyhydroxy structure, with stronger intermolecular forces and good crystallinity. Therefore, the binding force between the sugar materials and the perovskite solar cell materials and the encapsulation cover plate is stronger. At the same time, the melting point of the sugar materials is higher, making it not easy to soften and fail. Moreover, the thermal expansion coefficient of the sugar materials is smaller, which can inhibit the thermal expansion of the internal materials of the perovskite solar cell under working conditions, thus significantly improving the light stability of the battery.

[0022] 2. The present invention provides a method for encapsulating a perovskite solar cell using sugar materials as the encapsulation material. The time from the molten state to the solid state is short, the encapsulation speed is fast, and no additional pressure is required. The molten sugar materials can quickly and efficiently remove the air between the perovskite solar cell and the cover plate material by using the weight of the cover plate. The sugar encapsulation material is green and environmentally friendly, and inexpensive. The encapsulation process is simple, with high repeatability, and has little impact on the intrinsic performance of the perovskite solar cell, and can significantly improve the light stability of the battery, showing prospects for industrial application. Detailed implementation mode

[0023] The following examples further illustrate the technical solutions of the present invention, but do not limit the protection scope of the present invention. For example, the encapsulation materials and methods can be applied to perovskite solar cell device structures other than those described in this example. The encapsulation materials are not limited to the two types of sugars described in this example, but are solids with similar properties.

[0024] The following examples and the perovskite solar cells used have the following structure:

[0025] Example 1:

[0026] A method for encapsulating a perovskite solar cell with sugar materials is provided, including the following steps:

[0027] 1) Prepare a perovskite solar cell. The structure starting from the light-receiving surface is, in sequence, an FTO conductive glass, a 20-nanometer SnO2 electron transport layer, a 300-nanometer FAPbI3 perovskite layer (FA is the formamidinium group), a 200-nanometer organic hole transport layer, and a 80-nanometer gold thin film is vacuum-evaporated as the top electrode.

[0028] 2) Take a certain amount of rock sugar and heat it on a hot stage to melt at about 185 °C. Dip one side of the cover glass into the melted rock sugar. After the molten rock sugar levels off, stick the rock sugar surface onto the gold electrode of the above perovskite solar cell. After the rock sugar cools and solidifies, the encapsulation is completed. The thickness of the rock sugar layer after cooling is 1 mm.

[0029] Under standard sunlight, continuously test the parameters such as the photoelectric conversion efficiency of the encapsulated perovskite solar cell.

[0030] Example 2:

[0031] A method for encapsulating a perovskite solar cell with a saccharide material, comprising the following steps:

[0032] 1) Prepare a perovskite solar cell, and the structure starting from the light-receiving surface is successively FTO conductive glass, a 20-nanometer SnO2 electron transport layer, a 300-nanometer FAPbI3 perovskite layer (FA is a formamidinium group), a 200-nanometer organic hole transport layer, and a 150-nanometer silver thin film is vacuum-evaporated as the top electrode.

[0033] 2) Take a certain amount of isomaltose and heat it on a hot stage to melt at about 170 °C. Dip one side of a cover glass into the melted isomaltose. After the molten isomaltose levels off, stick the isomaltose side onto the silver electrode of the perovskite solar cell. After the isomaltose cools and solidifies, the encapsulation is completed; the thickness of the isomaltose layer after cooling is 1 mm.

[0034] Under standard sunlight, continuously test parameters such as the photoelectric conversion efficiency of the encapsulated perovskite solar cell.

[0035] Comparative Example 1:

[0036] A method for encapsulating a perovskite solar cell with a film, comprising the following steps:

[0037] 1) The perovskite solar cell is the same as in Example 2.

[0038] 2) On the top electrode of the perovskite solar cell, first place a PIB (polyisobutylene) film of appropriate size, then cover a cover glass of appropriate size, and then place it in a laminator for lamination and encapsulation. The vacuum pumping time is 150 seconds, the lamination time is 150 seconds, the temperature is 85 °C, and the pressure is 80 kPa; the thickness of the obtained film encapsulation layer is 1 mm.

[0039] Under standard sunlight, continuously test parameters such as the photoelectric conversion efficiency of the encapsulated perovskite solar cell.

[0040] Comparative Example 2:

[0041] A method for encapsulating a perovskite solar cell with a film, comprising the following steps:

[0042] 1) The perovskite solar cell is the same as in Example 1.

[0043] 2) On the top electrode of the perovskite solar cell, first place a POE (polyolefin elastomer) film of appropriate size, then cover a cover glass of appropriate size, and then place it in a laminator for lamination and encapsulation. The vacuum pumping time is 150 seconds, the lamination time is 150 seconds, the temperature is 85 °C, and the pressure is 80 kPa; the thickness of the obtained film encapsulation layer is 1 mm.

[0044] Under standard sunlight, continuously test parameters such as the photoelectric conversion efficiency of the encapsulated perovskite solar cells.

[0045] Comparative Example 3:

[0046] Provide a paraffin encapsulation method for perovskite solar cells, including the following steps:

[0047] 1) The perovskite solar cell is the same as in Example 1.

[0048] 2) Take a certain amount of paraffin and heat it on a hot stage to melt at about 80 °C. Dip one side of the cover glass into the melted paraffin. After the molten paraffin levels off, stick the paraffin side on the gold electrode of the perovskite solar cell. After the paraffin cools and solidifies, the encapsulation is completed; the thickness of the obtained paraffin encapsulation layer is 1 mm.

[0049] Under standard sunlight, continuously test parameters such as the photoelectric conversion efficiency of the encapsulated perovskite solar cells.

[0050] Comparative Example 4:

[0051] Provide an unencapsulated perovskite solar cell, including the following steps:

[0052] Prepare a perovskite solar cell. The structure starting from the light-irradiated surface is successively FTO conductive glass, a 20-nanometer SnO2 electron transport layer, a 300-nanometer FAPbI3 perovskite layer (FA is the formamidinium group), a 200-nanometer organic hole transport layer, and a 80-nanometer gold thin film is vacuum-evaporated as the top electrode.

[0053] Under standard sunlight, continuously test parameters such as the photoelectric conversion efficiency of the unencapsulated perovskite solar cells.

[0054] Perform a light stability test on the devices of Examples 1-2 and Comparative Examples 1-4. The results are shown in Table 1. Compared with the film-encapsulated cells in Comparative Examples 1 and 2 and the unencapsulated cells in Comparative Example 3, the cells encapsulated with rock sugar in Example 1 and the cells encapsulated with isomaltose in Example 2 both have good light stability and can maintain an initial efficiency of more than 80%. Thus, it can be seen that this encapsulation method using sugar materials is applicable to perovskite solar cells and can effectively improve the stability of the cells.

[0055] Table 1 Stability of the photoelectric conversion efficiency of perovskite solar cells

[0056]

[0057]

[0058] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. Application of a saccharide material in encapsulating a perovskite solar cell, characterized in that, The application specifically is: uniformly coat the molten sugar material on one side of the encapsulation cover plate, and then cover the side of the encapsulation cover plate with the sugar material onto the top electrode of the pre-prepared perovskite solar cell, and cooling and solidifying to complete the encapsulation.

2. The application according to claim 1, characterized in that, The sugar material is a solid sugar compound that melts at 100 - 200 °C and solidifies after cooling.

3. The application according to claim 1, characterized in that, The sugar material is a monosaccharide, disaccharide or sugar alcohol.

4. The application according to claim 2 or 3, characterized in that, The sugar material is rock sugar or isomaltose.

5. The application according to claim 1, characterized in that The perovskite solar cell has a basic structure including a transparent conductive substrate, an electron transport layer, a perovskite light absorption layer, a hole transport layer and a top electrode layer.

6. A method for encapsulating a sugar-based material of a perovskite solar cell, characterized in that, It includes the following steps: Step 1. Heat the sugar material to melt it to form a molten state with fluidity. Step 2. Uniformly coat the molten sugar material on one side of an appropriately sized encapsulation cover plate to form an encapsulation layer. Step 3. Cover the encapsulation layer onto the pre-prepared perovskite solar cell, where the side with the molten sugar material is in contact with the top electrode side of the perovskite solar cell. Step 4. After the molten sugar material cools to a solid, the encapsulation is completed.

7. The encapsulation method according to claim 6, wherein The thickness of the encapsulation layer after cooling is 0.5 - 2 mm.

8. The encapsulation method according to claim 6, wherein The encapsulation cover plate is an airtight material.

9. The encapsulation method according to claim 6, wherein In Step 3, hold one side of the encapsulation cover plate with tweezers, with the side covered with the molten sugar material facing down, make the opposite side first contact one side of the top electrode surface of the perovskite solar cell, and then lower the height of the other side of the encapsulation cover plate to make it cover the whole.

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