Flexible perovskite photovoltaic device

Abstract

The embodiment of the present application provides a kind of flexible perovskite photovoltaic device, wherein the flexible perovskite photovoltaic device includes: perovskite photovoltaic cell layer;Water oxygen barrier film layer, at least covering two sides of perovskite photovoltaic cell layer, respectively forming first water oxygen barrier film and second water oxygen barrier film on two sides of perovskite photovoltaic cell layer;And elastic encapsulation layer, water oxygen barrier film layer is covered;Wherein, the Young's modulus of above layer structure satisfies the following relationship: perovskite photovoltaic cell layer>water oxygen barrier film layer>elastic encapsulation layer;The thickness of elastic encapsulation layer>the thickness of water oxygen barrier film layer>the thickness of perovskite photovoltaic cell layer.The flexible perovskite photovoltaic device provided in the embodiment of the present application makes that the flexible perovskite photovoltaic device of the present application will not cause appearance damage of device or water oxygen barrier film surface when bending is used, and guarantees photoelectric conversion efficiency, improves the service life of device.

Description

Technical Field

[0001] This application belongs to the field of perovskite technology, and particularly relates to a flexible perovskite photovoltaic device. Background Technology

[0002] Perovskite photovoltaic devices are one of the most disruptive technologies in the solar energy field in recent years. They use materials with a perovskite crystal structure (usually organic-inorganic hybrid lead halide) as light-absorbing layers to convert light energy into electrical energy.

[0003] Current rigid perovskite solar photovoltaic modules are typically encapsulated as follows: an electron or hole transport layer, a perovskite light-absorbing layer, a hole or electron transport layer, and a top electrode are sequentially fabricated on a transparent conductive glass (bottom electrode). Finally, a cover glass is bonded to the top using an encapsulating film to complete the rigid perovskite photovoltaic module encapsulation. This rigid encapsulation method results in a heavier and thicker solar photovoltaic module, which is not conducive to its application in lightweight and thin consumer electronics products. Furthermore, existing transparent conductive glass and cover glass still have the disadvantages of being fragile, easily broken, and inflexible.

[0004] Current encapsulation methods for flexible perovskite solar photovoltaic modules involve sequentially fabricating a perovskite photovoltaic cell on a transparent conductive film (lower electrode), consisting of an electron or hole transport layer, a perovskite light-absorbing layer, a hole or electron transport layer, and a top electrode. The flexible perovskite is then encapsulated using upper and lower water and oxygen barrier films. This flexible encapsulation method uses a plastic substrate instead of glass, solving the problems of traditional glass being fragile, easily broken, and inflexible. However, this results in the plastic film being easily scratched, dented, and damaged, thus affecting the photovoltaic cell. Furthermore, the thinner the overall thickness of the device, the more easily it is subjected to bending and damage to the surface of the device or barrier film, thereby affecting the photoelectric conversion efficiency. Utility Model Content

[0005] In view of this, this application provides a flexible perovskite photovoltaic device to solve the technical problem that existing photovoltaic devices suffer surface damage to the device or barrier film when bent, thereby affecting the photoelectric conversion efficiency.

[0006] In a first aspect, embodiments of this application provide a flexible perovskite photovoltaic device, comprising:

[0007] Perovskite photovoltaic cell layer;

[0008] A water-oxygen barrier film layer, covering at least both sides of the perovskite photovoltaic cell layer, wherein a first water-oxygen barrier film and a second water-oxygen barrier film are respectively formed on both sides of the perovskite photovoltaic cell layer; and

[0009] An elastic encapsulation layer covers the water and oxygen barrier film layer. The elastic encapsulation layer forms a first encapsulation layer on the side of the first water and oxygen barrier film away from the perovskite photovoltaic cell layer, and forms a second encapsulation layer on the side of the second water and oxygen barrier film away from the perovskite photovoltaic cell layer.

[0010] The Young's modulus of the above-layer structure satisfies the following relationship: the perovskite photovoltaic cell layer > the water and oxygen barrier film layer > the elastic encapsulation layer;

[0011] The thickness of the first encapsulation layer is greater than the thickness of the first water-oxygen barrier film, which is greater than the thickness of the perovskite photovoltaic cell layer. The thickness of the second encapsulation layer is greater than the thickness of the second water-oxygen barrier film, which is greater than the thickness of the perovskite photovoltaic cell layer.

[0012] In some embodiments, the Young's modulus of the elastic encapsulation layer is <0.5 GPa, and the Shore A hardness is <60.

[0013] In some embodiments, the thickness of the first encapsulation layer is 50–5000 μm, and the thickness of the second encapsulation layer is 50–5000 μm. Preferably, the thickness of the first encapsulation layer is equal to the thickness of the second encapsulation layer.

[0014] In some embodiments, the thickness of the first water-oxygen barrier film is 10–100 μm, and the thickness of the second water-oxygen barrier film is 10–100 μm. Preferably, the thickness of the first water-oxygen barrier film is equal to the thickness of the second water-oxygen barrier film.

[0015] In some embodiments, the Young's modulus of the first water-oxygen barrier membrane and the second water-oxygen barrier membrane is 0.5 to 100 GPa.

[0016] In some embodiments, the first water-oxygen barrier membrane includes a first substrate and a first barrier layer disposed on the first substrate, wherein the first barrier layer is connected to the perovskite photovoltaic cell layer.

[0017] In some embodiments, the second water-oxygen barrier film includes a second substrate and a second barrier layer disposed on the second substrate, wherein the second barrier layer is connected to the perovskite photovoltaic cell layer.

[0018] In some embodiments, the thickness of the first substrate and the second substrate is 10 to 100 μm.

[0019] In some embodiments, the first substrate and the second substrate are any one of PI transparent optical film, PET transparent optical film, and PC transparent optical film.

[0020] In some embodiments, the thickness of the first barrier layer and the second barrier layer is 10 to 300 nm.

[0021] In some embodiments, the first barrier layer and the second barrier layer are inorganic oxide films or composite films of organic resin and inorganic oxides.

[0022] In some embodiments, the perovskite photovoltaic cell layer includes a first electrode layer, an electron transport layer, a perovskite light-absorbing layer, an electron-hole layer, and a second electrode layer stacked together; or the perovskite photovoltaic cell layer includes a first electrode layer, an electron-hole layer, a perovskite light-absorbing layer, an electron transport layer, and a second electrode layer stacked together.

[0023] In some embodiments, the flexible perovskite photovoltaic device further includes an encapsulating adhesive layer, which includes a first adhesive layer and a second adhesive layer. The first adhesive layer is located between the second electrode layer and the second water-oxygen barrier film, and the second adhesive layer is located on the periphery of the perovskite photovoltaic cell layer. The second adhesive layer is connected to the first water-oxygen barrier film and the second water-oxygen barrier film.

[0024] The flexible perovskite photovoltaic device provided in this application applies a "gradient stacking" design to its encapsulation. The flexible perovskite photovoltaic device, from the inside out, includes a perovskite photovoltaic cell layer, a water-oxygen barrier film layer, and an elastic encapsulation layer. The flexible encapsulation layer protects the water-oxygen barrier film layer, maintaining high flexibility even with increased overall thickness, thus enabling flexible bending. Specifically, the gradient stacking design includes two aspects: a thickness gradient (elastic encapsulation layer > water-oxygen barrier film layer > perovskite photovoltaic cell layer) and a Young's modulus gradient (perovskite photovoltaic cell layer > water-oxygen barrier film layer > elastic encapsulation layer). The perfect combination of modulus and thickness gradients ensures that external stress is attenuated layer by layer before reaching the perovskite photovoltaic cell layer. The thick, soft outer layer absorbs most of the impact and bending strain, while the moderately thick and stiff water-oxygen barrier film layer further disperses stress and protects itself, ultimately resulting in only minimal stress reaching the thin and brittle perovskite photovoltaic cell layer. This allows the device to withstand thousands of bending cycles without significant damage, meeting the requirements of flexible / wearable applications. A high-barrier-performance water-oxygen barrier film layer is placed immediately adjacent to the perovskite photovoltaic cell layer and protected by an external elastic encapsulation layer. The elastic encapsulation layer protects the water-oxygen barrier film layer from mechanical damage (cracks, scratches), maintaining its barrier integrity. Simultaneously, the elastic encapsulation layer itself also provides some auxiliary barrier function. The thickest and lowest-modulus elastic encapsulation layer dominates the device's flexibility, allowing it to be easily rolled or fitted to curved surfaces. Although the internal water-oxygen barrier film layer and perovskite photovoltaic cell layer are relatively rigid, their thin thickness and encapsulation by soft materials minimize the negative impact on overall flexibility. This ensures that the flexible perovskite photovoltaic device of this application does not suffer cosmetic damage to the device or the surface of the water-oxygen barrier film during bending use, while maintaining photoelectric conversion efficiency and improving the device's lifespan. Attached Figure Description

[0025] To more clearly illustrate the technical solutions in the embodiments of this application, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0026] Figure 1 This is a schematic diagram of the structure of the flexible perovskite photovoltaic device provided in the embodiments of this application. Figure 1 ;

[0027] Figure 2 This is a schematic diagram of the structure of the flexible perovskite photovoltaic device provided in the embodiments of this application. Figure 2 ;

[0028] Figure 3 This is a schematic diagram of the structure of the flexible perovskite photovoltaic device provided in the embodiments of this application. Figure 3 ;

[0029] Figure 4 This is a schematic diagram of the structure of the flexible perovskite photovoltaic device provided in the embodiments of this application. Figure 4 ;

[0030] Figure 5 This is a schematic diagram of the structure of the water and oxygen barrier film layer in the flexible perovskite photovoltaic device provided in the embodiments of this application;

[0031] Figure 6 This is a schematic diagram of the structure of the first water-oxygen barrier film and the first electrode layer in the flexible perovskite photovoltaic device provided in this application embodiment. Figure 1 ;

[0032] Figure 7 This is a schematic diagram of the structure of the first water-oxygen barrier film and the first electrode layer in the flexible perovskite photovoltaic device provided in this application embodiment. Figure 2 ;

[0033] Figure 8 This is a schematic diagram of the structure of the first water-oxygen barrier film and the first electrode layer in the flexible perovskite photovoltaic device provided in this application embodiment. Figure 3 ;

[0034] Figure 9 This is a schematic diagram of the structure of the flexible perovskite photovoltaic device provided in the embodiments of this application. Figure 5 .

[0035] The attached icon numbers are as follows:

[0036] 10. Perovskite photovoltaic cell layer; 11. First electrode layer; 12. Electron transport layer; 13. Perovskite light-absorbing layer; 14. Electron-hole layer; 15. Second electrode layer;

[0037] 20. Water and oxygen barrier film layer; 21. First water and oxygen barrier film; 211. First substrate; 212. First barrier layer; 22. Second water and oxygen barrier film; 221. Second substrate; 222. Second barrier layer;

[0038] 30. Flexible encapsulation layer; 31. First encapsulation layer; 32. Second encapsulation layer;

[0039] 40. Encapsulating adhesive layer; 41. First adhesive layer; 42. Second adhesive layer. Detailed Implementation

[0040] In the following description, specific details such as particular system architectures and techniques are set forth for illustrative purposes and not for limitation, in order to provide a thorough understanding of the embodiments of this application. However, those skilled in the art will understand that the embodiments of this application can also be implemented in other embodiments without these specific details. In other instances, detailed descriptions of well-known systems, apparatuses, circuits, and methods are omitted so as not to obscure the description of the embodiments of this application with unnecessary detail.

[0041] It should also be understood that the term "and / or" as used in the specification of embodiments of this application and the appended claims refers to any combination of one or more of the associated listed items and all possible combinations, and includes such combinations.

[0042] It should be noted that when a component is referred to as being "fixed to" or "set on" another component, it can be directly on or indirectly on that other component. When a component is referred to as being "connected to" another component, it can be directly connected to or indirectly connected to that other component.

[0043] It should be understood that the terms "length", "width", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", and "outer" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing the embodiments of this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the embodiments of this application.

[0044] Furthermore, in the description of the embodiments and the appended claims of this application, the terms "first," "second," "third," etc., are used only for distinguishing descriptions and should not be construed as indicating or implying relative importance.

[0045] In the description of embodiments in this application, references to "some embodiments" or "some embodiments" mean that one or more embodiments of this application include a specific feature, structure, or characteristic described in connection with that embodiment. Therefore, the phrases "in some embodiments," "in some embodiments," "in other embodiments," "in still other embodiments," etc., appearing in different parts of this specification do not necessarily refer to the same embodiments, but rather mean "one or more, but not all, embodiments," unless otherwise specifically emphasized. The terms "comprising," "including," "having," and variations thereof mean "including but not limited to," unless otherwise specifically emphasized. "A plurality" refers to two or more.

[0046] The current encapsulation method for flexible perovskite solar photovoltaic modules is shown in the figure below. A perovskite photovoltaic cell is fabricated by sequentially layering an electron or hole transport layer, a perovskite light-absorbing layer, a hole or electron transport layer, and an upper electrode on a transparent conductive film. Subsequently, a water-oxygen barrier film is used to encapsulate the flexible perovskite. This flexible encapsulation method uses a plastic substrate instead of glass, solving the problems of fragility, breakage, and inflexibility of traditional products. However, this results in the plastic film being easily scratched, dented, and damaged, thus affecting the photovoltaic cell. The thinner the overall thickness, the easier it is for the photovoltaic device or the barrier film surface to be damaged during bending, thus affecting the photoelectric conversion efficiency. Increasing the thickness of the water-oxygen barrier film or adding a hardening layer for protection will affect the flexible bending characteristics. The thicker the perovskite module, the more difficult it is to achieve flexible bending; the harder the surface of the plastic film, the more difficult it is to achieve flexible bending.

[0047] Based on this, this application proposes a novel flexible perovskite photovoltaic encapsulation design, which uses a "gradient stacking" method to encapsulate the flexible perovskite photovoltaic device. This application utilizes a soft, elastic encapsulation layer to protect the water and oxygen barrier film layer, and can maintain a high degree of flexibility even with an increased total thickness.

[0048] The first aspect of this application provides a flexible perovskite photovoltaic device, such as... Figure 1 and Figure 2 As shown, it includes a perovskite photovoltaic cell layer 10, a water and oxygen barrier film layer 20, and an elastic encapsulation layer 30.

[0049] The water and oxygen barrier film layer 20 covers at least both sides of the perovskite photovoltaic cell layer 10, and a first water and oxygen barrier film 21 and a second water and oxygen barrier film 22 are formed on both sides of the perovskite photovoltaic cell layer 10, respectively.

[0050] The elastic encapsulation layer 30 covers the water and oxygen barrier film layer 20. The elastic encapsulation layer 30 forms a first encapsulation layer 31 on the side of the first water and oxygen barrier film 21 away from the perovskite photovoltaic cell layer 10, and forms a second encapsulation layer 32 on the side of the second water and oxygen barrier film 22 away from the perovskite photovoltaic cell layer 10.

[0051] The Young's modulus of the perovskite photovoltaic cell layer 10, the water and oxygen barrier film layer 20, and the elastic encapsulation layer 30 satisfy the following relationship: perovskite photovoltaic cell layer 10 > water and oxygen barrier film layer 20 > elastic encapsulation layer 30.

[0052] The thickness of the first encapsulation layer 31 is greater than the thickness of the first water and oxygen barrier film 21 and the thickness of the perovskite photovoltaic cell layer 10. The thickness of the second encapsulation layer 32 is greater than the thickness of the second water and oxygen barrier film 22 and the thickness of the perovskite photovoltaic cell layer 10.

[0053] The flexible perovskite photovoltaic device provided in this application application utilizes a "gradient stacking" design in its encapsulation. The flexible perovskite photovoltaic device, from the inside out, comprises a perovskite photovoltaic cell layer 10, a water-oxygen barrier film layer 20, and an elastic encapsulation layer 30. The flexible encapsulation layer 30 protects the water-oxygen barrier film layer 20, maintaining high flexibility even with an increased overall thickness, thus enabling flexible bending. Specifically, the gradient stacking design includes two aspects: a thickness gradient (elastic encapsulation layer 30 > water-oxygen barrier film layer 20 > perovskite photovoltaic cell layer 10) and a Young's modulus gradient (perovskite photovoltaic cell layer 10 > water-oxygen barrier film layer 20 > elastic encapsulation layer 30). This perfect combination of modulus and thickness gradients ensures that external stress is attenuated layer by layer before reaching the perovskite photovoltaic cell layer 10. A thick, soft outer layer absorbs most of the impact and bending strain, while a medium-thickness and stiffness water-oxygen barrier film 20 further disperses stress and protects itself, ultimately resulting in minimal stress reaching the thin and brittle perovskite photovoltaic cell layer 10. This allows the device to withstand thousands of bending cycles without significant damage, meeting the requirements of flexible / wearable applications. The high-barrier water-oxygen barrier film 20 is placed immediately adjacent to the perovskite photovoltaic cell layer 10 and protected by an external elastic encapsulation layer 30. The elastic encapsulation layer 30 protects the water-oxygen barrier film 20 from mechanical damage (cracks, scratches), maintaining its barrier integrity. Simultaneously, the elastic encapsulation layer 30 itself also provides some auxiliary barrier function. The thickest and lowest modulus elastic encapsulation layer 30 dominates the device's flexibility, allowing it to be easily rolled up or fitted to curved surfaces. Although the internal water and oxygen barrier film layer 20 and perovskite photovoltaic cell layer 10 are relatively rigid, their thin thickness and soft material covering minimize the negative impact on overall flexibility. This ensures that the flexible perovskite photovoltaic device of this application will not suffer any appearance damage to the device or the surface of the water and oxygen barrier film when bent, while guaranteeing photoelectric conversion efficiency and improving the service life of the device.

[0054] It should be noted that, as Figure 1 and Figure 2 As shown, the water and oxygen barrier film layer 20 covers at least both sides of the perovskite photovoltaic cell layer 10. The two sides of the perovskite photovoltaic cell layer 10 refer to the two sides in the thickness direction of the device (i.e., the stacking direction of the perovskite photovoltaic cell layer 10). The water-oxygen barrier film layer 20 covering at least the two sides of the perovskite photovoltaic cell layer 10 includes the following situations: First, the water-oxygen barrier film layer 20 is disposed on both sides of the perovskite photovoltaic cell layer 10, forming the aforementioned first water-oxygen barrier film 21 and second water-oxygen barrier film 22; Second, the water-oxygen barrier film layer 20 completely covers the perovskite photovoltaic cell layer 10, not only forming the aforementioned first water-oxygen barrier film 21 and second water-oxygen barrier film 22 on both sides of the perovskite photovoltaic cell layer 10, but also covering the periphery of the perovskite photovoltaic cell layer 10; Third, the water-oxygen barrier film layer 20, in addition to forming the aforementioned first water-oxygen barrier film 21 and second water-oxygen barrier film 22 on both sides of the perovskite photovoltaic cell layer 10, also covers at least one side of the perovskite photovoltaic cell layer 10.

[0055] In applications, the water and oxygen barrier film 20 mainly functions to effectively block external moisture and oxygen from penetrating into the internal structure of the perovskite photovoltaic device (especially the light absorption layer in the perovskite material, i.e., the functional layer), thereby effectively preventing the decomposition of the perovskite material and improving the overall lifespan of the perovskite photovoltaic device.

[0056] In application, the thickness of the first encapsulation layer 31 is 50–5000 μm, and the thickness of the second encapsulation layer 32 is 50–5000 μm. Preferably, the thickness of the first encapsulation layer 31 is equal to the thickness of the second encapsulation layer 32. The thickness of the first water-oxygen barrier film 21 is 10–100 μm, and the thickness of the second water-oxygen barrier film 22 is 10–100 μm. Preferably, the thickness of the first water-oxygen barrier film 21 is equal to the thickness of the second water-oxygen barrier film 22; the Young's modulus of the first water-oxygen barrier film 21 and the second water-oxygen barrier film 22 is 0.5–100 GPa. The differences and corresponding effects under the gradient stacking design are as follows:

[0057] Thickness differences: Flexible encapsulation layer 30 (50–5000 μm) > Water and oxygen barrier layer 20 (10–100 μm) > Perovskite photovoltaic cell layer 10 (0.5–10 μm); Sufficient thickness (typically in the micrometer range) is required to ensure its compactness and pinhole-free nature for effective water and oxygen barrier. Sufficient thickness is also needed to provide effective stress buffer space, physical protection, and act as a final environmental barrier. The innermost layer (the thinnest perovskite photovoltaic cell layer 10) meets photoelectric functional requirements while minimizing its own mechanical vulnerability due to thickness. The middle layer (medium-thickness water and oxygen barrier layer 20) provides sufficient but not redundant thickness to ensure high barrier performance while avoiding excessive sacrifice of flexibility. Its thickness is greater than the perovskite layer to provide effective coverage and protection. The outermost layer (the thickest flexible encapsulation layer 30) has sufficient thickness to accommodate greater deformation, more effectively absorb and dissipate mechanical energy, and significantly improve protection. It provides additional protection against physical damage such as scratches, abrasions, and impacts. While its water and oxygen barrier properties may not be as strong as dedicated barrier films, the increased thickness extends the water and oxygen permeation path, providing additional environmental protection time. As the thickest and softest layer, it determines the radius of curvature and flexibility of the device when bent. The thick, soft layer makes the device easier to bend without generating excessive internal stress. An optimized thickness distribution for function and protection is achieved. The perovskite layer is thin and functional, the barrier layer is of moderate thickness to ensure core protection functions, and the elastic encapsulation layer 30 maximizes its stress buffering and physical protection. This thickness gradient, combined with the modulus gradient, results in excellent flexibility, resistance to bending fatigue, and physical protection.

[0058] Young's modulus: Perovskite photovoltaic cell layer 10 (>100 GPa) > Water and oxygen barrier film layer 20 (0.5–100 GPa) > Elastic encapsulation layer 30 (<0.5 GPa). The core objective is to prevent externally applied bending, tensile, or impact stress from being directly transmitted to the fragile perovskite active layer. The innermost layer (high-modulus perovskite photovoltaic cell layer 10) itself needs a certain structural integrity to support the photoelectric conversion function. Its high modulus makes it less prone to large deformation. The intermediate layer (medium-modulus water and oxygen barrier film layer 20), typically composed of relatively rigid inorganic materials or dense polymers, is inherently brittle. Its modulus is higher than the outermost layer but lower than the perovskite layer, serving two functions: primary stress dispersion, receiving and partially dispersing some stress from the external elastic layer; and providing physical support for the perovskite layer and acting as the main water and oxygen barrier. It also needs a certain rigidity to maintain its density and barrier performance. The outermost layer (low-modulus elastic encapsulation layer 30) undergoes large, recoverable deformation first when the device is subjected to bending, pressing, or impact. This absorbs and dissipates most of the external mechanical energy, greatly preventing external stress from being transmitted to the more rigid barrier layer and the brittle perovskite layer. This also prevents the water-oxygen barrier layer 20 from cracking and failing due to direct external force. External stress is significantly attenuated as it passes through the elastic encapsulation layer 30, reducing the stress transmitted to the water-oxygen barrier layer 20. After further dispersion / attenuation by the water-oxygen barrier layer 20 (whose modulus is still higher than that of the elastic encapsulation layer 30), the stress finally reaching the perovskite photovoltaic cell layer 10 becomes very small, greatly reducing the risk of cracking, delamination, or failure of the perovskite layer. This significantly improves the mechanical durability of the device under repeated bending, curling, or minor impacts.

[0059] In some embodiments, the Young's modulus of the elastic encapsulation layer 30 is <0.5 GPa, and its Shore A hardness is <60. With its low Young's modulus (soft elasticity), the material of the elastic encapsulation layer 30 readily undergoes large deformations under stress, efficiently absorbing external bending, impact, or vibration energy, significantly reducing the mechanical stress transmitted to the internal perovskite photovoltaic cell layer 10. When photovoltaic devices with the elastic encapsulation layer 30 are repeatedly bent or stretched, the elastic encapsulation layer 30 dissipates energy through a viscoelastic energy dissipation mechanism, protecting the brittle perovskite layer from fatigue damage. In applications, the material of the elastic encapsulation layer 30 can be a soft and elastic material such as polydimethylsiloxane, silicone, rubber, silicone rubber, or acrylic adhesive.

[0060] In applications, such as Figure 4As shown, the perovskite photovoltaic cell layer 10 includes a first electrode layer 11, an electron transport layer 12, a perovskite light-absorbing layer 13, an electron-hole layer 14, and a second electrode layer 15 stacked together, or the perovskite photovoltaic cell layer 10 includes the same first electrode layer 11, electron-hole layer 14, perovskite light-absorbing layer 13, electron transport layer 12, and second electrode layer 15 stacked together. The conventional structure (first electrode layer 11 / electron transport layer 12 / perovskite layer / hole transport layer / second electrode layer 15) follows the traditional electron-hole flow design. The electron transport layer 12 (ETL) is located adjacent to the lower side of the perovskite light-absorbing layer 13, and can quickly extract photogenerated electrons and inject them into the first electrode layer 11 (cathode), reducing electron recombination at the perovskite interface; the hole transport layer (HTL) is located above the perovskite light-absorbing layer 13, and efficiently transports holes to the second electrode (anode). The advantages are: a short and direct electron transport path, making it particularly suitable for materials with high electron mobility and significantly improving electron collection efficiency; simultaneously, the hole transport layer being on top allows for compatibility with more stable polymer materials, reducing the risk of environmental corrosion. The overall structure and technology are mature, suitable for rigid or flexible substrates, and offer clear room for optimization of photoelectric conversion efficiency. The inverted structure (first electrode layer 11 / hole transport layer / perovskite layer / electron transport layer 12 / second electrode layer 15) reverses the carrier transport direction: the hole transport layer (HTL) directly contacts the first electrode (anode), preferentially extracting holes; the electron transport layer 12 (ETL) is located above the perovskite, guiding electrons to the second electrode (cathode). The core advantages are: the hole transport layer being on the bottom layer allows for the use of highly stable inorganic materials or low-defect organic materials, effectively suppressing interface degradation; the electron transport layer 12 being on the top layer avoids the high-temperature sintering step in traditional structures, making it compatible with low-temperature flexible processes. Furthermore, the inverted structure reduces direct contact between the perovskite and metal electrodes, lowering the risk of ion migration and making it more suitable for tandem battery integration and long-term reliability requirements.

[0061] In some embodiments, such as Figure 3 and Figure 4As shown, the flexible perovskite photovoltaic device also includes an encapsulating adhesive layer 40, which includes a first adhesive layer 41 and a second adhesive layer 42. The first adhesive layer 41 is located between the second electrode layer 15 and the second water-oxygen barrier film 22, and the second adhesive layer 42 is located on the periphery of the perovskite photovoltaic cell layer 10. The second adhesive layer 42 is connected to the first water-oxygen barrier film 21 and the second water-oxygen barrier film 22. The first adhesive layer 41 is used to bond and encapsulate the second water-oxygen barrier film 22 to the second electrode layer 15 of the perovskite photovoltaic cell layer 10. The perovskite photovoltaic cell layer 10 is located between the first water-oxygen barrier film 21 and the second water-oxygen barrier film 22, with the second adhesive layer 42 on its side. The second adhesive layer 42 serves to connect the first water-oxygen barrier film 21 and the second water-oxygen barrier film 22. Furthermore, the sides of the second adhesive layer 42, the first water and oxygen barrier film 21, and the second water and oxygen barrier film 22 are covered by the elastic encapsulation layer 30 to protect the entire perovskite photovoltaic cell layer 10, prevent the interior from being corroded by external moisture, and improve its service life.

[0062] In some embodiments, such as Figure 5 As shown, the first water and oxygen barrier film 21 includes a first substrate 211 and a first barrier layer 212 disposed on the first substrate 211, the first barrier layer 212 being connected to the perovskite photovoltaic cell layer 10; the second water and oxygen barrier film 22 includes a second substrate and a second barrier layer disposed on the second substrate, the second barrier layer being connected to the perovskite photovoltaic cell layer 10. Thus, a layer structure of the perovskite photovoltaic cell layer 10 can be sequentially fabricated on the first substrate 211.

[0063] In applications, the water and oxygen barrier film consists of a plastic substrate and a barrier layer. The thickness of the plastic substrate can be 10–100 μm, and the material can be a transparent optical film such as polyimide (PI), polyethylene terephthalate (PET), or polycarbonate (PC). The barrier layer can be a single layer or multiple layers of stacked inorganic materials, such as silicon oxide, silicon nitride, aluminum oxide, or a multilayer stack of organic and inorganic materials. Alternatively, the water and oxygen barrier layer material can also be an inorganic oxide film, such as silicon oxide, aluminum oxide, silicon nitride, or zinc oxide, with a thickness between 10 and 300 nm. The barrier layer material can also be a composite film of organic and inorganic oxides, such as a two-layer film (alumina / organic resin / alumina) or a multilayer film (silicon nitride / organic resin / silicon nitride / organic resin / silicon oxide), where the inorganic oxide thickness is less than 300 nm. Specifically, the thickness of the first or second barrier layer 212 is 10 nm–300 nm. In applications, the thickness of the barrier layer can be any value within the range of 10nm to 300nm, such as 10nm, 20nm, 50nm, 100nm, 120nm, 150nm, 200nm, 250nm, or 300nm. When the barrier layer is less than 10nm, inorganic oxide films are prone to pinhole defects due to process fluctuations, leading to localized failures; while a thickness of 10-50nm ensures density while maintaining low material usage. For organic-inorganic composite barrier layers or multilayer stacked structures (such as "sandwich" structures), appropriately increasing the thickness (e.g., 200nm) can compensate for single-layer microcracks through redundant design, improving overall barrier reliability. In a specific embodiment, a multilayer structure of alternating SiO2 and polyimide deposition is used, with each layer being 50-100nm and the total thickness being 200-300nm, resulting in a barrier performance improvement of more than 10 times. In the 100–300 nm range, organic layers (such as polyurethane) can act as stress buffer layers to absorb strain during bending, while inorganic layers provide barrier functions. The combination of the two achieves a balance between rigidity and flexibility.

[0064] In application, the positional relationship between the first water-oxygen barrier membrane 21 and the first electrode layer 11 can be as follows: Figure 6 As shown, the first electrode layer 11 is shorter than the first water-oxygen barrier film 21, leaving gaps at both ends of the first electrode layer 11 to allow for sealing by the subsequent encapsulating adhesive layer 40 or sealing by the second water-oxygen barrier film 22. In other embodiments, the positional relationship between the first water-oxygen barrier film 21 and the first electrode layer 11 can be as follows: Figure 7 As shown, the first electrode layer 11 and the first water-oxygen barrier membrane 21 have the same length, and the first electrode layer 11 is located on the first water-oxygen barrier membrane 21. In other embodiments, the positional relationship between the first water-oxygen barrier membrane 21 and the first electrode layer 11 can be as follows: Figure 8 As shown, the first electrode layer 11 is embedded in the first water and oxygen barrier film 21, which can effectively protect the first electrode layer 11 and also prevent water and oxygen from entering.

[0065] In applications, such as Figure 9 As shown, the second adhesive layer 42 is located on the side of the perovskite photovoltaic cell layer 10. The second adhesive layer 42 is connected to the first water-oxygen barrier film 21 and the second water-oxygen barrier film 22. The elastic encapsulation layer 30 is connected to the first water-oxygen barrier film 21 and the second water-oxygen barrier film 22, but not to the second adhesive layer 42. In this way, the first water-oxygen barrier film 21 and the second water-oxygen barrier film 22 completely cover and protect the perovskite photovoltaic cell layer 10.

[0066] This application also provides a method for fabricating a flexible perovskite photovoltaic device, comprising:

[0067] S10, Provide the first water and oxygen barrier membrane 21;

[0068] S20. A perovskite battery layer is obtained by sequentially forming a first electrode layer 11, an electron-hole layer 14, a perovskite light-absorbing layer 13, an electron transport layer 12 and a second electrode layer 15 on the first water-oxygen barrier film 21. Alternatively, a perovskite battery layer is obtained by sequentially forming a first electrode layer 11, an electron transport layer 12, a perovskite light-absorbing layer 13, an electron-hole layer 14 and a second electrode layer 15 on the first water-oxygen barrier film 21.

[0069] S30. A second water-oxygen barrier film 22 is formed on the side of the second electrode layer 15 away from the perovskite battery layer.

[0070] S40, an elastic encapsulation layer 30 is formed on the first water and oxygen barrier film 21 and the second water and oxygen barrier film 22 to obtain a flexible perovskite photovoltaic device.

[0071] The method for fabricating flexible perovskite photovoltaic devices provided in this application uses a first water-oxygen barrier film 21 as the growth substrate, providing initial environmental isolation throughout the entire battery layer manufacturing process to prevent water and oxygen erosion during perovskite processing. Water-oxygen barrier films (S10 / S30) are directly deposited on both sides of the battery layer to form a dense sandwich structure, maximizing environmental stability. The electrode / functional layers can be processed on the flexible barrier film using low-temperature solution processing (such as slot coating) to avoid high-temperature damage and ensure compatibility with roll-to-roll mass production. The elastic encapsulation is integrated, with the final elastic layer (S40) simultaneously covering the double barrier films, achieving synergistic protection of mechanical stress buffering and environmental sealing, while avoiding delamination risks. This method, through optimization of the "barrier-power generation-barrier-buffering" sequence, simultaneously addresses the environmental sensitivity and mechanical fragility of flexible devices in a single process, significantly improving mass production feasibility and product reliability.

[0072] In step S10, in some embodiments, providing the first water-oxygen barrier membrane 21 includes:

[0073] Provide a first substrate 211;

[0074] A first barrier layer 212 is formed on a first substrate 211 to obtain a first water and oxygen barrier film 21. The first substrate 211 uses a flexible substrate (such as PET / polyimide) as a mechanical carrier, imparting bending resistance to the barrier film; an inorganic barrier layer (such as Al) is directly grown on the substrate. v O3, SiN x To prevent high-temperature damage and maintain film flexibility, the first barrier layer 212 is prepared before battery manufacturing, isolating water and oxygen permeation from the process source and protecting the perovskite layer from degradation during subsequent deposition. Independent control of the substrate and barrier layer can achieve an ultra-low defect interface, improving overall water and oxygen barrier performance. This design makes rigid encapsulation materials flexible, building a stable and reliable protective starting point at the front end of the process, providing a "shield" of protection for environmentally sensitive materials throughout the entire process.

[0075] In applications, water- and oxygen-barrier materials (SiN2) are deposited on 50μm plastic substrates using magnetron sputtering or chemical vapor deposition. x SiO x A first water and oxygen barrier film 21 is obtained by depositing a film (with a total thickness of less than 3 μm) onto the surface of a substrate.

[0076] After step S20 and before step S30, in some embodiments, before the second water-oxygen barrier film 22 is formed on the side of the second electrode layer 15 away from the perovskite cell layer, the following is included:

[0077] An encapsulating adhesive layer 40 is formed on the side of the second electrode layer 15 away from the perovskite light-absorbing layer 13. The encapsulating adhesive layer 40 extends towards the periphery of the perovskite battery layer and is connected to the first water and oxygen barrier film 21. The encapsulating adhesive layer 40 extends laterally from the surface of the second electrode to the edge of the first barrier film, directly wrapping the sidewall of the battery layer, completely blocking the lateral permeation path of water and oxygen, and solving the pain point of the "edge effect" in traditional encapsulation. The encapsulating adhesive layer 40 forms a double seal of chemical bonding and physical filling with the first and second barrier films, eliminating interlayer micro-gaps. The adhesive layer is pre-placed before the deposition of the second barrier film to avoid bending micro-cracks caused by direct contact between the rigid film and the electrode, while providing an elastic transition substrate for subsequent lamination. The liquid adhesive spin coating / spray coating can precisely control the extension width and is compatible with the encapsulation requirements of irregularly shaped devices.

[0078] This design upgrades the "point-to-surface" seal to a "three-dimensional full-coverage" seal through topology optimization of the adhesive layer space, effectively improving device lifespan and achieving synergistic mechanical protection and environmental barrier in a single step.

[0079] In applications, the specific process flow for fabricating flexible perovskite photovoltaic devices is as follows:

[0080] S10. On a 50μm first substrate 211, water- and oxygen-barrier material (SiN) is deposited using magnetron sputtering or chemical vapor deposition. xSiO x The transparent conductive material (with a total thickness of less than 3 μm) is deposited on the surface of the first substrate 211, and the first water and oxygen barrier film 21 is obtained by sputtering the transparent conductive material onto the first barrier layer 212 using a magnetron sputtering device.

[0081] S20. Perform the first laser etching to pattern the transparent conductive layer into a sub-cell. First, apply the hole transport layer material using a slit coating machine. After coating, place it on a heating platform for drying at 120°C for 5 minutes. Next, apply the perovskite light-absorbing layer 13 using a slit coating machine. First, rapidly evacuate the solvent and place it on a heating platform for drying at 150°C for 10 minutes. Then, use a vacuum evaporation process to deposit the electron transport layer 12 (C... 60 Fullerene and BCP (bath copper spirit) are vapor-deposited onto the perovskite light-absorbing layer 13, and a second laser etching is performed to pattern the hole and electron transport layer 12 and the perovskite light-absorbing layer 13. Then, the second electrode layer 15 is sputtered onto the perovskite layer using a magnetron sputtering device, and a third laser etching is performed to connect the layers in series.

[0082] S30. The water and oxygen barrier film is bonded and encapsulated with the perovskite photovoltaic cell layer 10 using an encapsulating adhesive material. The perovskite photovoltaic cell layer 10 is located between the first water and oxygen barrier film 21 and the second water and oxygen barrier film 22, and the side part is the encapsulating adhesive layer 40.

[0083] S40. The flexible encapsulation material is coated onto the water-oxygen encapsulation layer by scraping and then cured. The curing conditions are 80℃ and 10min to obtain a flexible perovskite photovoltaic device.

[0084] In the above embodiments, the descriptions of each embodiment have different focuses. For parts that are not described in detail or recorded in a certain embodiment, please refer to the relevant descriptions of other embodiments.

[0085] The above-described embodiments are only used to illustrate the technical solutions of the embodiments of this application, and are not intended to limit them. Although the embodiments of this application have been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application, and should all be included within the protection scope of the embodiments of this application.

Claims

1. A flexible perovskite photovoltaic device, characterized in that, include: Perovskite photovoltaic cell layer; A water-oxygen barrier film layer, covering at least both sides of the perovskite photovoltaic cell layer, wherein a first water-oxygen barrier film and a second water-oxygen barrier film are respectively formed on both sides of the perovskite photovoltaic cell layer; and An elastic encapsulation layer covers the water and oxygen barrier film layer. The elastic encapsulation layer forms a first encapsulation layer on the side of the first water and oxygen barrier film away from the perovskite photovoltaic cell layer, and forms a second encapsulation layer on the side of the second water and oxygen barrier film away from the perovskite photovoltaic cell layer. The Young's modulus of the above-layer structure satisfies the following relationship: the perovskite photovoltaic cell layer > the water and oxygen barrier film layer > the elastic encapsulation layer; The thickness of the first encapsulation layer is greater than the thickness of the first water-oxygen barrier film, which is greater than the thickness of the perovskite photovoltaic cell layer. The thickness of the second encapsulation layer is greater than the thickness of the second water-oxygen barrier film, which is greater than the thickness of the perovskite photovoltaic cell layer.

2. The flexible perovskite photovoltaic device of claim 1, wherein, The elastic encapsulation layer has a Young's modulus of <0.5 GPa and a Shore A hardness of <60.

3. The flexible perovskite photovoltaic device of claim 1, wherein, The thickness of the first encapsulation layer is 50–5000 μm, and the thickness of the second encapsulation layer is 50–5000 μm.

4. The flexible perovskite photovoltaic device of claim 1, wherein, The thickness of the first water-oxygen barrier membrane is 10–100 μm, and the thickness of the second water-oxygen barrier membrane is 10–100 μm.

5. The flexible perovskite photovoltaic device of claim 1, wherein, The Young's modulus of the first water-oxygen barrier membrane and the second water-oxygen barrier membrane is 0.5 to 100 GPa.

6. The flexible perovskite photovoltaic device of claim 1, wherein, The first water and oxygen barrier membrane includes a first substrate and a first barrier layer disposed on the first substrate, wherein the first barrier layer is connected to the perovskite photovoltaic cell layer. And / or, the second water and oxygen barrier film includes a second substrate and a second barrier layer disposed on the second substrate, the second barrier layer being connected to the perovskite photovoltaic cell layer.

7. The flexible perovskite photovoltaic device of claim 6, wherein, The thickness of the first substrate and the second substrate is 10 to 100 μm; And / or, the first substrate and the second substrate are any one of polyimide transparent optical film, polyethylene terephthalate transparent optical film, and polycarbonate transparent optical film.

8. The flexible perovskite photovoltaic device of claim 6, wherein, The thicknesses of the first barrier layer and the second barrier layer are 10–300 nm; And / or, the first barrier layer and the second barrier layer are inorganic oxide films or composite films of organic resin and inorganic oxides.

9. The flexible perovskite photovoltaic device according to any one of claims 1 to 8, wherein, The perovskite photovoltaic cell layer includes a first electrode layer, an electron transport layer, a perovskite light-absorbing layer, an electron-hole layer, and a second electrode layer stacked together, or the perovskite photovoltaic cell layer includes a first electrode layer, an electron-hole layer, a perovskite light-absorbing layer, an electron transport layer, and a second electrode layer stacked together.

10. The flexible perovskite photovoltaic device of claim 9, wherein, The flexible perovskite photovoltaic device further includes an encapsulating adhesive layer, which includes a first adhesive layer and a second adhesive layer. The first adhesive layer is located between the second electrode layer and the second water-oxygen barrier film, and the second adhesive layer is located on the periphery of the perovskite photovoltaic cell layer. The second adhesive layer is connected to the first water-oxygen barrier film and the second water-oxygen barrier film.

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