A flexible perovskite solar cell

Abstract

The present application provides a flexible perovskite solar cell, which includes a metal electrode layer, a hole transport layer, a perovskite functional layer, an electron transport layer, a flexible electrode layer and a flexible substrate layer, wherein a barrier anti-reflection film is formed on the flexible substrate layer, and the barrier anti-reflection film is composed of organic sublayers and inorganic sublayers formed continuously and alternately, and each organic sublayer and inorganic sublayer respectively serves as an anti-reflection film sublayer corresponding to light of different wavelengths, thereby achieving high light transmittance and low water vapor transmittance. The composition and thickness of each layer are precisely controlled by molecular layer deposition and atomic layer deposition technology, and the defects of the inorganic sublayer are decoupled by the organic sublayer during the stacking process, thereby enhancing the flexibility of the material and the stability of the battery, and combining the control of the refractive index of each layer to improve the stability and light utilization rate of the flexible perovskite solar cell.

Description

[Technical field]

[0002] The present application belongs to the technical field of solar cells, and in particular, relates to a flexible perovskite solar cell and a method for manufacturing the same. [Background technology]

[0004] Perovskite cells use perovskite materials as a photosensitive layer to efficiently convert sunlight into electrical energy. Under laboratory conditions, the photoelectric conversion efficiency of perovskite solar cells has exceeded 26.2%, and according to theoretical predictions, its efficiency limit is as high as 33%. With the increasing maturity of technology and the accelerated advancement of industrialization, perovskite cells are gradually moving from the laboratory to the market. Many domestic and foreign companies have entered the field of perovskite cells, invested in the construction of production lines, and expanded production capacity. At present, the stability of perovskite cells and perovskite solar cells is still a major challenge on the road to industrialization. This type of battery is extremely sensitive to water vapor. Once exposed to a humid environment, its performance often drops sharply in just a few hundred hours.

[0005] Therefore, solving the impact of water vapor on perovskite solar cells and improving their stability have become the focus of current research. At the same time, it should be noted that since light needs to reach the photoelectric conversion layer as much as possible, under this requirement, the encapsulation layer needs to have a high light transmittance, so the design of the encapsulation layer needs to take into account both the water vapor transmittance requirements and the light transmittance requirements. [Summary of the invention]

[0007] The purpose of the present application is to provide a perovskite solar cell having an encapsulation layer with low water vapor permeability and high light transmittance. By designing the structure of the barrier anti-reflection film, the functions of blocking water vapor and enhancing light transmittance are integrated into one packaging structure, thereby maintaining the performance of the perovskite solar cell while reducing the weight.

[0008] The purpose of the present application is achieved through the following technical solutions: a flexible perovskite solar cell, comprising in sequence a metal electrode layer, a hole transport layer, a perovskite functional layer, an electron transport layer, a flexible electrode layer, and a flexible substrate layer, wherein a barrier antireflection film is formed on one side of the flexible substrate layer opposite to the flexible electrode layer;

[0009] The barrier anti-reflection film comprises organic sublayers and inorganic sublayers formed continuously and alternately, and each layer of the organic sublayer and the inorganic sublayer independently forms an anti-reflection film sublayer corresponding to light of different wavelengths;

[0010] The water vapor transmission rate of the barrier anti-reflection film is less than 10 -5 g·m -2 ·day -1 The light transmittance of the blocking anti-reflection film is greater than 85%.

[0011] In one embodiment, the organic sublayer in the blocking antireflection film is formed by a molecular layer deposition method, and the inorganic sublayer is formed by an atomic layer deposition method.

[0012] In one embodiment, the refractive index of each of the organic sub-layer and the inorganic sub-layer in the blocking anti-reflection film gradually increases in a direction toward the flexible base layer.

[0013] In one embodiment, the thickness of each of the organic sub-layer and the inorganic sub-layer in the blocking anti-reflection film gradually decreases in a direction toward the flexible base layer.

[0014] In one embodiment, the refractive index of the flexible electrode layer is greater than the refractive index of the flexible substrate layer, and the refractive index of the flexible substrate layer is greater than the refractive index of any of the organic sublayers or the inorganic sublayers in the barrier anti-reflection film.

[0015] In one embodiment, the blocking anti-reflection film covers all outer surfaces of the flexible perovskite solar cell.

[0016] Compared with the prior art, the present application has the following beneficial effects: by continuously alternating the formation of organic sublayers and inorganic sublayers as a barrier anti-reflection film, an organic / inorganic stacking method is used to achieve a higher water vapor barrier rate. Since the organic sublayer in the stacked layer can "decouple" the defects of the adjacent inorganic sublayer, the material can be more flexible and not easy to crack, thereby ensuring the flexibility of the perovskite solar cell. In addition, by regulating the materials and thicknesses of each organic sublayer and inorganic sublayer, anti-reflection sub-films corresponding to different wavelengths of light are formed respectively, so that the light transmittance of the barrier anti-reflection film is improved. In addition, by using molecular layer deposition and atomic layer deposition respectively, the composition and thickness of each layer are precisely controlled, and the stability and light utilization rate of the flexible perovskite solar cell are improved by combining the control of the refractive index of each layer.

Brief Description of the Drawings

[0018] Figure 1 It is a schematic diagram of the structure of the flexible perovskite solar cell of the present application.

[0019] Figure 2 It is a schematic diagram of the structure step by step for making the flexible perovskite solar cell of the present application.

[0020] Explanation of the reference numerals: 100, flexible electrode layer; 200, flexible substrate layer; 300, electron transport layer; 400, perovskite functional layer; 500, hole transport layer; 600, metal electrode layer; 700, blocking antireflection film; 710, organic sublayer; 720, inorganic sublayer. [Specific implementation method]

[0022] In order to make the above-mentioned purposes, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are described in detail below in conjunction with the accompanying drawings. It is to be understood that the specific embodiments described herein are only used to explain the present application, rather than to limit the present application. It should also be noted that, for ease of description, only some structures related to the present application are shown in the accompanying drawings, rather than all structures. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of this application.

[0023] The terms "including" and "having" and any variations thereof in this application are intended to cover non-exclusive inclusions. For example, a process, method, system, product or device comprising a series of steps or units is not limited to the listed steps or units, but may optionally include steps or units not listed, or may optionally include other steps or units inherent to these processes, methods, products or devices.

[0024] Reference to "embodiments" herein means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present application. The appearance of the phrase in various locations in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0025] In order to make the perovskite solar cell more stable, it is necessary to design the packaging structure so that it has low water vapor transmittance and high light transmittance. Based on the above purpose, the present application provides a perovskite solar cell including a barrier anti-reflection film 700, which integrates the functions of blocking water vapor and enhancing light transmittance into one packaging structure. Please refer to Figure 1 , Figure 1This is a schematic diagram of the structure of the flexible perovskite solar cell of the present application. The flexible perovskite solar cell comprises, in sequence, a metal electrode layer 600, a hole transport layer 500, a perovskite functional layer 400, an electron transport layer 300, a flexible electrode layer 100, and a flexible substrate layer 200. The flexible substrate layer 200 forms a barrier anti-reflection film 700 on one side relative to the flexible electrode layer 100. The design of the flexible perovskite solar cell is to increase its flexibility and durability while maintaining efficient energy conversion. The metal electrode layer 600 is arranged at the top for collecting and conducting the generated current. It has high conductivity and good adhesion to ensure efficient transmission of current. The hole transport layer 500 is located between the metal electrode layer 600 and the perovskite functional layer 400, collects and transmits holes while preventing the backflow of electrons, thereby improving the efficiency of the battery. The perovskite functional layer 400 is the core part of the battery, responsible for absorbing light energy and converting it into electrical energy. The perovskite material has excellent light absorption and carrier transport capabilities, which is the key to achieving efficient solar energy conversion. The specific material of the perovskite functional layer 400 in this application is not limited, and any perovskite material and the corresponding manufacturing method can be applied to the perovskite solar cell of this application. The electron transport layer 300 is located between the perovskite functional layer 400 and the flexible electrode layer 100. Its main function is to transmit electrons and form a good interface contact with the perovskite functional layer 400 to ensure efficient transmission of electrons and prevent the backflow of holes.

[0026] The flexible electrode layer 100 of the present application is formed into an independent flexible electrode material, and then the flexible electrode material is used as the initial substrate, and other layers are made based on the flexible electrode material. The flexible electrode material is used as the other end electrode of the battery, and is usually made of conductive polymer or metal material. This layer needs to have high conductivity and good flexibility, adapt to various bending and deformation while ensuring the stable transmission of current. The flexible substrate layer 200 is the supporting structure of the entire battery, providing the necessary mechanical strength and flexibility, and needs to have excellent weather resistance and corrosion resistance. In the current prior art, a flexible substrate is usually used as the initial substrate, but the production of flexible electrodes on a flexible substrate will have the defect of unstable flexible electrodes, and it is difficult to ensure uniform quality. In addition, the equipment units or modules required by the flexible electrode manufacturing process are inconsistent with the equipment units or modules required by the other material layer processes, which will increase the equipment-related costs. If the relevant equipment units or modules are configured in the production line of perovskite solar cells, the production of the flexible electrode can only be dedicated to the production of perovskite solar cells. When debugging the production line, more process control needs to be paid attention to, which will increase the relevant costs.

[0027] The blocking anti-reflection film 700 includes an organic sublayer 710 and an inorganic sublayer 720 that are continuously and alternately formed. Each layer of the organic sublayer 710 and the inorganic sublayer 720 independently forms an anti-reflection film sublayer corresponding to light of different wavelengths. The organic / inorganic stacking method achieves a higher water vapor barrier rate. Since the organic sublayer 710 in the stacked layer can "decouple" the defects of the adjacent inorganic sublayer 720, the material can be more flexible and not easy to crack, thereby ensuring the flexibility of the perovskite solar cell. When the organic / inorganic film can be stacked well and stably, the water vapor barrier effect can be ensured. The above is one of the main technical effects of the blocking anti-reflection film 700 in the present application. Furthermore, since each layer of the organic sublayer 710 and the inorganic sublayer 720 of the present application independently forms an anti-reflection film sublayer corresponding to light of different wavelengths, when light of different wavelengths passes through the barrier anti-reflection film 700 of the present application, the reflected light of the upper and lower interfaces of the film can also interfere with each other, thereby enhancing the transmittance, reducing the reflection and absorption of light by the barrier anti-reflection film 700, and improving the transmittance of the barrier anti-reflection film 700 as a whole. Through the above-mentioned structural design, the water vapor transmittance of the barrier anti-reflection film 700 in the flexible perovskite solar cell of the present application is less than 10 -5 g·m -2 ·day -1 The light transmittance of the blocking anti-reflection film 700 is greater than 85%.

[0028] In the barrier anti-reflection film 700 of the present application, the organic sublayer 710 can be formed by coating or the like, and the inorganic sublayer 720 can be formed by magnetron sputtering or the like. In a preferred embodiment, the organic sublayer 710 in the barrier anti-reflection film 700 is formed by a molecular layer deposition method, and the inorganic sublayer 720 is formed by an atomic layer deposition method. The organic sublayer 710 is formed by a molecular layer deposition method. This method is based on the self-assembly reaction of the precursor molecules and the substrate, and can precisely control the thickness and uniformity of the film at the atomic scale, and is usually carried out at a lower temperature, which makes it particularly suitable for temperature-sensitive flexibility. By precisely controlling the thickness and refractive index of the organic sublayer 710, an anti-reflection effect can be formed within a specific wavelength range, so that more light can pass through and enter the perovskite functional layer 400, thereby improving the photoelectric conversion efficiency of the battery. The inorganic sublayer 720 is formed by an atomic layer deposition method. The atomic layer deposition method forms a thin film by alternately exposing it to two or more reactant precursors. Each exposure forms a thin film with an atomic thickness on the surface. The formed inorganic sublayer 720 usually has excellent thermal stability and can maintain stable performance over a wide temperature range, which is very important for improving the thermal stability and durability of the battery. The molecular layer deposition method and the atomic layer deposition method both have the characteristics of being able to form a uniform and dense film on a surface of complex shape. The thickness of the film formed can be precisely controlled, and it can also be uniformly formed on a surface with complex morphology, which can ensure the precise control of the composition and thickness of the material, so the anti-reflection effect of a single layer can be achieved as designed.

[0029] Specifically, the refractive index of each layer of the organic sublayer 710 and the inorganic sublayer 720 in the blocking anti-reflection film 700 gradually increases in the direction toward the flexible substrate layer 200. When light passes through different media, it will encounter changes in the refractive index, which may cause light reflection or scattering, thereby reducing the transmittance of light. In the flexible perovskite solar cell, the design of the blocking anti-reflection film 700 is to solve this problem. By gradually increasing the refractive index of each layer of the organic sublayer 710 and the inorganic sublayer 720 in the direction toward the flexible substrate layer 200, a refractive index gradient can be formed. The effect is that when light enters the blocking anti-reflection film 700 from the perovskite functional layer 400, due to the gradual change in the refractive index, the light can pass through the interface between different layers more smoothly, instead of encountering reflection caused by a large refractive index difference. This design makes the propagation of light in the blocking anti-reflection film 700 smoother, reduces light reflection and scattering, and thus improves the transmittance of light.

[0030] Specifically, the thickness of each layer of the organic sublayer 710 and the inorganic sublayer 720 in the barrier anti-reflection film 700 gradually decreases in the direction toward the flexible substrate layer 200. According to the anti-reflection principle, the thickness of the anti-reflection film is determined according to the wavelength of the light that needs to be enhanced. In order to avoid light from reflecting outward from the barrier anti-reflection film 700, the present application has designed and optimized the refractive index of each layer in the organic / inorganic stack, and the refractive index will gradually change. By gradually reducing the thickness of the organic sublayer 710 and the inorganic sublayer 720, a specific optical path difference is formed between different layers. The optical path difference will cause interference between the reflected light, which can significantly reduce the reflection of light at the interface and improve the transmittance of light. The optimized design of the refractive index and thickness can achieve effective utilization of light of all bands, thereby improving the photoelectric conversion efficiency of perovskite solar cells.

[0031] In order to cooperate with the barrier anti-reflection film 700 to improve the utilization rate of light, the present application further optimizes the design of the flexible substrate layer 200 adjacent to the barrier anti-reflection film 700. The refractive index of the flexible electrode layer 100 is greater than the refractive index of the flexible substrate layer 200, and the refractive index of the flexible substrate layer 200 is greater than the refractive index of any of the organic sublayers 710 or the inorganic sublayers 720 in the barrier anti-reflection film 700. In this way, the flexible electrode layer 100, the flexible substrate layer 200, and the organic sublayer 710 and the inorganic sublayer 720 in the barrier anti-reflection film 700 have different refractive indices arranged according to the size of the refractive index. When light passes through, it is avoided to reflect outward as much as possible, which can optimize the propagation path of light inside the battery and enable more light to reach the perovskite functional layer 400.

[0032] Specifically, the barrier anti-reflection film 700 covers all outer surfaces of the flexible perovskite solar cell. The main function of the barrier anti-reflection film 700 is to increase the transmittance of light and reduce reflection. When the film layer covers all outer surfaces of the battery, it means that no matter from which direction the light shines on the battery, it can more effectively enter the interior of the battery through the barrier anti-reflection film 700, and thus be absorbed by the perovskite functional layer 400. The barrier anti-reflection film 700 not only has optical functions, but also has certain barrier properties. When the film layer covers all outer surfaces of the battery, it forms an all-round protective layer, which can effectively block the corrosion of water vapor, oxygen and other harmful substances in the external environment to the battery, and can further extend the service life of the battery.

[0033] This application further provides a method for manufacturing a flexible perovskite solar cell. Figure 2 , Figure 2The present invention is a schematic diagram of the structure of the flexible perovskite solar cell of the present invention. The flexible electrode layer 100 is selected as the initial growth substrate. A flexible base layer 200 is formed on one side of the flexible electrode layer 100. An electron transport layer 300, a perovskite functional layer 400, a hole transport layer 500 and a metal electrode layer 600 are sequentially formed on the other side of the flexible electrode layer 100. A barrier anti-reflection film 700 is formed on the surface of the flexible base layer 200 relative to the flexible electrode layer 100. In the prior art, the flexible base layer 200 is usually used as the initial substrate. If the flexible electrode layer 100 is directly made on the flexible base layer 200, the properties of the flexible electrode layer 100 will be unstable, and the cost of the perovskite solar cell production line equipment will be increased. The present invention directly uses the flexible electrode material as the starting substrate. It is only necessary to configure the components for making the perovskite battery layer and the barrier anti-reflection film 700 in the production line. In the organic / inorganic alternating stacked structure designed in the present invention, the organic material in the alternating structure can be used to form the flexible base layer 200, so as to reduce the configuration of raw materials as much as possible and make full use of the production line equipment. In the specific steps of preparing each layer of perovskite, a scribing step can also be used to use a laser beam to etch a specific pattern on the surface of the battery to achieve series connection of the batteries. The laser scribing process usually includes multiple scribings, each scribing is at a different position to achieve circuit connection inside the battery. The conventional scribing and series connection method of thin-film solar cells can be used, so the specific scribing positions, etc. are not specifically shown in the drawings of the specification.

[0034] The step of forming the barrier anti-reflection film 700 includes continuously and alternately forming an organic sublayer 710 and an inorganic sublayer 720. By adjusting the number, thickness, refractive index and other parameters of the organic sublayer 710 and the inorganic sublayer 720, a customized design of the performance of the barrier anti-reflection film 700 can be achieved. Since the organic sublayer 710 in the stacked layer can "decouple" the defects of the adjacent inorganic sublayer 720, the material can be more flexible and less prone to brittle cracking, thereby ensuring the flexibility of the perovskite solar cell. When the organic / inorganic film can be stacked well and stably, the water vapor barrier effect can be ensured.

[0035] By controlling the composition and thickness of each layer of the organic sublayer 710 and the inorganic sublayer 720, each layer of the organic sublayer 710 and the inorganic sublayer 720 is independently formed as an anti-reflection film sublayer corresponding to light of different wavelengths. The organic sublayer 710 and the inorganic sublayer 720 are continuously and alternately formed, and each layer independently serves as an anti-reflection film sublayer corresponding to light of different wavelengths. The interference principle of light is utilized, so that when light passes through the blocking anti-reflection film 700, the reflected light at the upper and lower interfaces of the film can interfere with each other, thereby significantly reducing the reflection and absorption of light, enhancing the transmittance of light, and improving the transmittance of the blocking anti-reflection film 700 as a whole, so that more light can be absorbed by the perovskite functional layer 400. For the specific film layer of the barrier anti-reflection film 700, in a preferred embodiment, both layers of the barrier anti-reflection film 700 are organic sublayers 710. This arrangement can better transition with other material layers, thereby forming a better overall structure, especially when other layers do not adopt the molecular layer deposition method, the organic sublayer 710 in the barrier anti-reflection film 700 can achieve better interface transition through molecular layer deposition. The organic sublayer referred to in this application is an organic layer based on metal elements, such as an organic metal material based on aluminum formed by using alcohol or diol. Of course, other materials in the art that can meet the preparation method and property requirements of this application can be used to form the anti-reflection film layer.

[0036] Specifically, the organic sublayer 710 is formed by a molecular layer deposition method, and the inorganic sublayer 720 is formed by an atomic layer deposition method. The above two methods can not only form thin films uniformly and densely on surfaces with complex morphologies, but also achieve precise control of the film thickness. Through fine regulation, extremely high accuracy of material composition and thickness is ensured. Combined with the technical solution of the present application, an anti-reflection film layer of the required thickness can be accurately formed, and the composition of the entire layer is uniform and the properties are stable.

[0037] Specifically, after forming the metal electrode layer 600, the blocking antireflection film 700 is formed on all outer surfaces of the battery using the molecular layer deposition method and the atomic layer deposition method. Due to the molecular layer deposition method and the atomic layer deposition method themselves, when the entire surface is required, it is easy to achieve complete coating of the outer surface.

[0038] In order to better protect the flexible perovskite solar cell, a flexible protective layer is further provided on the portion of the blocking anti-reflection film 700 corresponding to the flexible substrate layer 200. The material of the flexible protective layer is the same as that of the flexible substrate layer 200. In this manner, the blocking anti-reflection film 700 is disposed between two organic sublayers 710, and the blocking anti-reflection film 700 is not in direct contact with the outside, thereby avoiding possible influence on the blocking anti-reflection film 700. Since the flexible perovskite solar cell has light incident on one side of the blocking anti-reflection film 700, the surface will be exposed to the outside. In order to avoid possible damage caused by external contact, a flexible protective layer is further provided. Specific embodiments

[0040] The following is a further detailed description of a method for making a flexible perovskite solar cell of the present application. Since the perovskite solar cell of the present application is flexible and uses a flexible electrode material, it can be produced in a roll-to-roll manner, and the flexible electrode material is formed into a coil, wherein the flexible electrode material includes a front and a back, wherein the back includes a layer of completely insulating material, and the front has a conductive material, and the flexible electrode material coil is placed at the unwinding end of the production line. The unwinding flexible electrode material passes through an organic material coating chamber to form a flexible substrate layer on the back of the flexible electrode material. After forming the flexible substrate layer, the flexible electrode material passes through a first scribing line to divide the conductive material on the front of the flexible electrode material into independent areas, and then passes through an electron transport layer, a perovskite functional layer, and a hole transport layer to form a cavity, and sequentially forms an electron transport layer, a perovskite functional layer, and a hole transport layer to form a battery structure layer, and the formed battery structure layer is subjected to a second scribing line to divide the battery structure layer into different areas. Next, a metal electrode layer is prepared, and the flexible electrode material forming the battery structure layer is transferred to the magnetron sputtering chamber. The metal electrode layer is prepared by magnetron sputtering. After the metal electrode layer is formed, the third scribing is performed to realize the formation and series connection of different battery units of the perovskite solar cell. The flexible electrode materials forming each layer are further transferred to the molecular layer deposition chamber and the atomic layer deposition chamber. The molecular layer deposition chamber and the atomic layer deposition chamber are arranged alternately. After a plurality of alternating molecular layer deposition chambers and atomic layer deposition chambers are arranged alternately, a barrier anti-reflection film including an organic sublayer and an inorganic sublayer is formed, thereby completing the preparation of a flexible perovskite solar cell. After the production is completed, it is cut as needed, and continuous production is carried out in a roll-to-roll manner. The specific process of each step is controlled separately. In a further preferred scheme, a flexible protective layer can also be further formed on the back.

[0041] Embodiment 1

[0042] In the above formation step, a structure including 3 organic sublayers and 2 inorganic sublayers is selected, wherein the 2 inorganic sublayers are located between the 3 organic sublayers. By adjusting the raw materials, the refractive indexes selected in the direction toward the flexible substrate layer are 1.05, 1.1, 1.15, 1.2 and 1.25, respectively, and the refractive index gradually increases, corresponding to the wavelength ranges of light of 700-800nm, 600-700nm, 500-600nm, 450-500nm and 400-450nm, respectively. The corresponding sublayer thickness is calculated by taking the middle value of the wavelength range of light, and the corresponding thicknesses selected are 187.5nm, 148nm, 120nm, 100nm, and 85nm, respectively. The material system selects aluminum-based materials, and trimethylaluminum is used as a source for both atomic layer deposition and molecular layer deposition.

[0043] Embodiment 2

[0044] On the basis of the formation steps, a structure including 2 organic sublayers and 1 inorganic sublayer is formed, wherein the 1 inorganic sublayer is located between the 2 organic sublayers. By adjusting the raw materials, the refractive indices selected in the direction toward the flexible substrate layer are 1.05, 1.1 and 1.15, respectively, and the refractive index gradually increases, corresponding to the wavelength ranges of light of 600-800nm, 500-600nm, and 400-500nm, respectively. The middle value of the wavelength range of light is taken to calculate the corresponding sublayer thickness, and the selected corresponding thicknesses are 168nm, 125nm, 100nm, and 98nm, respectively.

[0045] The prepared flexible perovskite solar cell was tested for transmittance by retaining only the flexible substrate layer and removing other layers. The test results show that the transmittance of Example 1 is 93.5%, and the transmittance of Example 2 is 93.1%. Although Example 1 is thicker, it is still higher than that of Example 2, which shows that the more detailed the division of the wavelength range of light and the design of the anti-reflection film corresponding to the wavelength range can improve the transmittance of light.

[0046] By testing the photoelectric conversion efficiency, the photoelectric conversion efficiency of Example 2 (25.60%) is slightly lower than that of Example 1 (25.66%). After 30 days (outdoor operation), the photoelectric conversion efficiency of Example 1 is 23.85%, and the photoelectric conversion efficiency of Example 2 is 23.55%. The attenuation ratio of Example 1 is 7%, and the attenuation ratio of Example 2 is 8%. The barrier anti-reflection film with a multi-layer structure has a lower attenuation rate.

[0047] Comparative Example 1, Comparative Example 2

[0048] On the basis of Example 1 and Example 2, the blocking anti-reflection film is removed. Through testing, it is found that the initial photoelectric conversion efficiency of Example 1 is 25.78% relative to Example 1, which is slightly higher than the flexible perovskite solar cell with a blocking anti-reflection film (25.66%). It is speculated that the reason is that there is no blocking anti-reflection film to absorb or reflect light, but as time goes by, after 30 days, the attenuation rate without a blocking anti-reflection film (photoelectric conversion efficiency 12.38%) is significantly faster than the flexible perovskite solar cell with a blocking anti-reflection film (photoelectric conversion efficiency 23.85%), and the attenuation degree is greater than 50%. The flexible perovskite solar cell without a blocking anti-reflection film cannot meet the normal use requirements of the solar cell. In addition, through the bending test, the attenuation rate of the flexible perovskite solar cell without a blocking anti-reflection film after 50 bends is increased by about 10%, while the attenuation rate of the flexible perovskite solar cell with a blocking anti-reflection film is only increased by about 3%. In the comparison between Example 2 and Comparative Example 2, the same comparison results are also obtained.

[0049] Comparative Example 3, Comparative Example 4

[0050] On the basis of Example 1 and Example 2, the inorganic sublayer was prepared by magnetron sputtering, and the organic layer was formed by coating technology. After the formation, the photoelectric conversion efficiency, transmittance and attenuation rate were compared. By comparison, the transmittance of Comparative Example 3 and Comparative Example 4 decreased by about 1%, and the difference in photoelectric conversion efficiency was about 0.3%, but the attenuation rate remained almost the same, and no obvious difference was found. It can be seen that the structural design can significantly improve the attenuation, and further using the preparation method to control the thickness of the designed material layer can obtain better technical effects.

[0051] As can be seen from the foregoing, the present application provides a flexible perovskite solar cell that is efficient, stable and has excellent flexibility, and is composed of a metal electrode layer, a hole transport layer, a perovskite functional layer, an electron transport layer, a flexible electrode layer and a flexible substrate layer, wherein a unique barrier anti-reflection film is formed on the flexible substrate layer, and the film is composed of organic sublayers and inorganic sublayers formed in a continuous alternating manner, forming an organic / inorganic stacking structure, so that each organic sublayer and inorganic sublayer respectively serves as an anti-reflection film sublayer corresponding to light of different wavelengths, achieving high light transmittance and ensuring the photoelectric conversion efficiency of the solar cell. At the same time, the water vapor transmittance of the barrier anti-reflection film is low, which significantly improves the long-term stability of the perovskite solar cell.

[0052] In terms of manufacturing process, this application uses molecular layer deposition and atomic layer deposition technology to accurately control the composition and thickness of each layer. Through these two deposition technologies, the thickness and refractive index of each organic sublayer and inorganic sublayer can be accurately controlled, thereby achieving the anti-reflection effect corresponding to different wavelengths of light. In addition, in the stacked structure, the organic sublayer can "decouple" the defects of the adjacent inorganic sublayer, effectively improving the flexibility of the material and the overall stability of the battery.

[0053] Another innovation of the present application lies in the control of the refractive index of each layer. Through optimized design, the refractive index of the flexible electrode layer is greater than that of the flexible substrate layer, and the refractive index of the flexible substrate layer is greater than that of any organic sublayer or inorganic sublayer in the barrier anti-reflection film. This helps to reduce the reflection loss of light at the interface and avoid the internal light from diverging outward, thereby improving the light utilization rate of the solar cell.

[0054] In addition, the manufacturing method of the flexible perovskite solar cell of the present application uses a flexible electrode layer as the initial growth substrate, and after forming each functional layer in sequence, a barrier anti-reflection film is formed on the flexible base layer. By precisely controlling the deposition parameters and the number of layers, the performance of the barrier anti-reflection film can be optimized.

[0055] In summary, the flexible perovskite solar cell of the present application has the advantages of high efficiency, stability, and flexibility. Its unique barrier anti-reflection film design and precise manufacturing process provide new ideas for the commercial application of solar cells.

[0056] The above is only a specific implementation of the present application, and any other improvements made based on the concept of the present application are deemed to be within the protection scope of the present application.

Claims

1. A flexible perovskite solar cell, characterized in that: The invention comprises in sequence a metal electrode layer (600), a hole transport layer (500), a perovskite functional layer (400), an electron transport layer (300), a flexible electrode layer (100), and a flexible substrate layer (200), wherein a barrier anti-reflection film (700) is formed on one side of the flexible substrate layer (200) opposite to the flexible electrode layer (100); The barrier anti-reflection film (700) comprises organic sublayers (710) and inorganic sublayers (720) that are continuously and alternately formed, and each layer of the organic sublayer (710) and the inorganic sublayer (720) independently forms an anti-reflection film sublayer corresponding to light of different wavelengths; The water vapor transmission rate of the barrier anti-reflection film (700) is less than 10 -5 g·m -2 ·day -1 The light transmittance of the blocking anti-reflection film (700) is greater than 85%.

2. The flexible perovskite solar cell according to claim 1, characterized in that: The organic sublayer (710) in the blocking anti-reflection film (700) is formed by using a molecular layer deposition method, and the inorganic sublayer (720) is formed by using an atomic layer deposition method.

3. The flexible perovskite solar cell according to claim 1, characterized in that: The refractive index of each of the organic sublayer (710) and the inorganic sublayer (720) in the barrier anti-reflection film (700) gradually increases in a direction toward the flexible base layer (200).

4. The flexible perovskite solar cell according to claim 3, characterized in that: The thickness of each layer of the organic sublayer (710) and the inorganic sublayer (720) in the blocking anti-reflection film (700) gradually decreases in a direction toward the flexible base layer (200).

5. The flexible perovskite solar cell according to claim 1, characterized in that: The refractive index of the flexible electrode layer (100) is greater than the refractive index of the flexible substrate layer (200), and the refractive index of the flexible substrate layer (200) is greater than the refractive index of any one of the organic sublayer (710) or the inorganic sublayer (720) in the barrier anti-reflection film (700).

6. The flexible perovskite solar cell according to claim 1, characterized in that: The barrier anti-reflection film (700) covers all outer surfaces of the flexible perovskite solar cell.

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