A flexible perovskite solar cell and its fabrication method
By combining UV-resistant adhesive tape and specific UV wavelength irradiation with laser scribing, the problems of complex substrate bonding and peeling damage in the fabrication of flexible perovskite solar cells have been solved. This method achieves efficient and low-cost separation of flexible and rigid substrates, ensuring device performance and flatness.
Patent Information
- Application Number
- CN202610091938.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2026-01-23
- Publication Date
- 2026-05-26
AI Technical Summary
In the fabrication of flexible perovskite solar cells, the bonding between the flexible and rigid substrates is complex and the adhesion force is difficult to control, which makes the device prone to damage during peeling and easy to separate and warp during high-temperature processes, affecting performance.
A flexible substrate is temporarily fixed to a rigid substrate using UV-resistant adhesive tape. Specific UV wavelengths are used to irradiate the substrate to drastically reduce its adhesion, achieving non-destructive separation. Laser scribing is then used to create slits, ensuring the integrity and flatness of the film layer.
The bonding process was simplified, the stability of the flexible substrate in high-temperature processes was ensured, device damage and adhesive residue were avoided, costs were reduced and fabrication efficiency was improved.
Smart Images
Figure CN122094364A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the technical field of solar cells, and more particularly to a flexible perovskite solar cell and its fabrication method. Background Technology
[0002] Perovskite solar cells have attracted widespread attention due to their high efficiency, low cost, and solution-processability. Benefiting from the unique photoelectric properties of perovskite materials, such as high light absorption coefficients, ideal and tunable band gaps, and long charge diffusion lengths, the efficiency of perovskite solar cells has now exceeded 27%. In addition to their excellent photoelectric properties, perovskite itself possesses good mechanical flexibility and low-temperature solution processability, making flexible perovskite solar cells possible. Flexible perovskite solar cells hold promise for specific applications in unmanned systems, smart integrated buildings, wearable and portable electronic devices, and self-powered bioelectronic devices.
[0003] Because flexible substrates inherently possess a certain degree of curvature, they can bend under heated conditions due to thermal stress, leading to surface unevenness and uneven heating, which affects perovskite crystallization. Therefore, they are generally not used as the sole substrate for fabricating perovskite solar cells. Typically, in the fabrication of flexible perovskite solar cells, an adhesive layer is used to adhere the flexible substrate to a rigid glass substrate before the flexible device is fabricated. Afterward, the fabricated flexible perovskite is peeled off from the rigid glass. If the adhesive layer's adhesion is too strong, the flexible device can easily be damaged during peeling, thus affecting performance.
[0004] Currently, the bonding of flexible and rigid substrates has the following drawbacks: 1. The bonding process is complex. For example, with PDMS adhesive, a certain amount of adhesive needs to be prepared in different proportions. The preparation and bonding process is prone to generating air bubbles and misalignment. The adhesive curing process requires heating, which increases additional energy consumption. At the same time, it is difficult to control the flatness error of the entire surface to meet the coating standard. 2. Excessive adhesion: Using double-sided tape as the adhesive layer can easily cause the flexible substrate to bend significantly during peeling, leading to deformation, damage to the functional layer, and a decrease in performance. 3. During the annealing process, the flexible substrate is prone to separation from the rigid substrate, which can cause the flexible substrate to warp and the film surface to become uneven, affecting subsequent processes or performance. Summary of the Invention
[0005] The purpose of this invention is to overcome the shortcomings of existing technologies and provide a flexible perovskite solar cell and its fabrication method. This invention temporarily fixes a flexible substrate to a rigid substrate using UV-resistant adhesive tape, utilizing the flatness and temperature resistance of the rigid substrate to fabricate the flexible perovskite solar cell.
[0006] To achieve the above objectives, the technical solution adopted by the present invention is as follows: In a first aspect, the present invention provides a method for fabricating a flexible perovskite solar cell, comprising the following steps: (1) Obtain a rigid substrate, a flexible substrate and a UV anti-adhesion double-sided tape. The flexible substrate includes a flexible substrate and a conductive layer stacked together. Both surfaces of the UV anti-adhesion double-sided tape are provided with release protective films. The lower surface of the flexible substrate and the upper surface of the conductive layer are respectively provided with release protective films. (2) Remove the protective film from one surface of the UV anti-adhesion double-sided tape and attach the UV anti-adhesion double-sided tape to the upper surface of the rigid substrate; (3) Remove the protective film on the other side of the UV anti-adhesion double-sided tape and the protective film on the lower surface of the flexible substrate, and then attach the UV anti-adhesion double-sided tape to the lower surface of the flexible substrate. (4) Remove the protective film on the surface of the conductive layer, and then perform the first laser scribing on the flexible substrate to remove the conductive layer and form several uniformly spaced first grooves on the flexible substrate. (5) The first charge transport layer, the perovskite layer and the second charge transport layer are sequentially prepared from bottom to top on the upper surface of the substrate after the first laser scribing; (6) Perform a second laser scribing on the device prepared in step (5) to remove the second charge transport layer, the perovskite layer and the first charge transport layer, forming a number of second grooves; the second grooves are located on one side of the first groove; (7) After the second laser scribing, a metal electrode layer is prepared on the surface of the second charge transport layer; (8) Perform a third laser scribing on the device prepared in step (7) to form several third grooves, remove the metal electrode layer, the second charge transport layer, the perovskite layer and the first charge transport layer to obtain a perovskite solar energy device with a rigid substrate; the third groove is located on one side of the second groove and the second groove is located between the first groove and the third groove. (9) The perovskite solar cell device is irradiated with UV light of a specific wavelength, with an irradiation energy range of 300-800 mJ / cm. 2 The wavelength of the UV irradiation is 365 nm, 254 nm, or 395 nm. (10) Separate the flexible substrate and the rigid substrate to obtain a flexible perovskite solar cell.
[0007] The core characteristic of the UV anti-adhesion tape of this invention is that before irradiation with a specific UV wavelength, it has high adhesion (200~600 g / 25mm) and can fix a flexible substrate. After irradiation with a specific wavelength of UV light, such as 365 nm, 254 nm, or 395 nm, its adhesion decreases sharply (<10 g / 25mm), achieving non-destructive / residual separation of flexible and rigid substrates. The UV anti-adhesion tape of this invention is commercially available. Using other wavelengths of UV light, such as 532 nm, may result in ineffective debonding, or the adhesive layer may age without reducing adhesion or leave residue.
[0008] If the irradiation energy is too high in step (9), the adhesive will become brittle and easily tear; if the irradiation energy is too low, the adhesive will not be completely unbonded and will remain sticky.
[0009] Preferably, in step (1), the thickness of the rigid substrate is 2-4 mm, preferably 3.2 mm; the thickness of the flexible substrate is 100-200 μm, preferably 125 μm or 188 μm; and the thickness of the UV anti-adhesion double-sided tape is 60-80 μm, preferably 70 μm.
[0010] Preferably, the flexible substrate in step (1) is made of at least one of polyethylene terephthalate (PET), polyethylene naphthalate (PEN), and polyimide (PI).
[0011] Preferably, the conductive layer in step (1) is made of at least one of indium tin oxide (ITO), fluorine-doped tin oxide (FTO), aluminum-doped zinc oxide (AZO), and gallium-doped zinc oxide (GZO).
[0012] Preferably, in step (2), the UV anti-adhesion double-sided tape and the rigid substrate are pressed together by rollers or scrapers during the bonding process to eliminate air bubbles generated during the bonding process.
[0013] Preferably, in step (2), when the UV anti-adhesion double-sided tape and the rigid substrate are bonded, the pressure and speed of the roller are adjusted according to different tape types to achieve a suitable value. If the pressure is too high, the tape will deform. If the speed is too high, the air bubbles will not have time to escape.
[0014] Preferably, the width of the first groove in step (4) is 10-40 μm, for example, it can be 10μm, 15μm, 20μm, 25μm, 30μm, 35μm, 40μm or any two of these values. If the groove width is too narrow, it is easy to cause a short circuit because the flexible substrate needs to be bent during use. If the width is too wide, it will increase the dead zone area and affect the device efficiency.
[0015] Preferably, the depth of the first groove in step (4) is 300-500 nm, for example, it can be 300 nm, 350 nm, 400 nm, 450 nm, 500 nm or any two of these values. If the groove depth is too shallow, the conductive layer cannot be completely removed, and the sub-units cannot be insulated, ultimately causing a short circuit in the device; if the depth is too deep, it will damage the flexible substrate, forming a deep trench, making it difficult for the material to be evenly covered in the deep trench during the subsequent coating process, and it is easy to form a discontinuity or uneven thickness around the deep trench, ultimately causing a short circuit or failure of the device.
[0016] Preferably, in step (5), the thickness of the first charge transport layer is 20-40 nm; the thickness of the perovskite layer is 450-650 nm; and the thickness of the second charge transport layer is 250-350 nm.
[0017] Preferably, in step (5), the material of the first charge transport layer includes at least one of SnO2 and TiO2; the material of the perovskite layer is a conventional mixed cationic halide; and the material of the second charge transport layer includes at least one of Spiro-OMeTAD and PTAA.
[0018] Preferably, the process for preparing the first charge transport layer, the perovskite layer and the second charge transport layer in step (5) includes spin coating, wire rod coating or slot coating.
[0019] Preferably, in step (5), the upper surface of the flexible substrate is surface treated before the first charge transport layer is prepared. The surface treatment method includes plasma or UV plasma cleaning.
[0020] Preferably, the plasma has a power of 30-100 W and a duration of 1-5 min.
[0021] Preferably, the power of the UV plasma cleaning is 10–30 mW / cm². 2 The time is 5-15 minutes.
[0022] The power and time of plasma and UV plasma cleaning have a significant impact on device efficiency. If the power is too low or the time is too short, the surface cannot be effectively cleaned and activated, resulting in uneven coverage of the perovskite layer. If the power is too high or the time is too long, it may lead to excessive oxidation or damage to the substrate surface, both of which will cause a decrease in the efficiency of perovskite solar cells.
[0023] Preferably, the width of the second groove in step (6) is 80-150 μm, for example, it can be 80μm, 90μm, 100μm, 110μm, 120μm, 130μm, 140μm, 150μm or any two of these values.
[0024] Preferably, the depth of the second groove in step (6) is 700-900 nm, for example, it can be 700 nm, 750 nm, 800 nm, 850 nm, 900 nm or any two of these values.
[0025] Preferably, the width between the first groove and the second groove in step (6) is 30-80 μm, for example, it can be 30μm, 40μm, 50μm, 60μm, 70μm, 80μm or any two of these values.
[0026] Preferably, the thickness of the metal electrode layer in step (7) is 45-120 nm.
[0027] Preferably, the metal electrode layer in step (7) is prepared by thermal evaporation or magnetron sputtering.
[0028] Preferably, the metal electrode layer in step (7) includes an Au electrode layer, an Ag electrode layer, or a Cu electrode layer.
[0029] Preferably, the width of the third groove in step (8) is 15-35 μm, for example, it can be 15μm, 20μm, 25μm, 30μm, 35μm or any two of these values.
[0030] Preferably, the depth of the third groove in step (8) is 600-950 nm, for example, it can be 600 nm, 650 nm, 700 nm, 750 nm, 800 nm, 850 nm, 900 nm, 950 nm or any two of these values.
[0031] Preferably, the width between the second groove and the third groove in step (8) is 25-60 μm, for example, it can be 25μm, 30μm, 35μm, 40μm, 45μm, 50μm, 55μm, 60μm or any two of these values.
[0032] If the distance between the first and second grooves, or between the second and third grooves, is too large, it will result in a larger dead zone area, a smaller current, and affect the final efficiency of the device; if the distance is too small, it will easily increase the risk of short circuit in the device.
[0033] Secondly, the present invention also provides a flexible perovskite solar cell prepared by the above method.
[0034] Compared with the prior art, the beneficial effects of the present invention are as follows: (1) The present invention combines a flexible substrate and a rigid substrate by temporary bonding and slit coating and vacuum sputtering, which can improve the stability of the flexible substrate in high temperature and vacuum processes, while ensuring that no damage occurs to each film layer during the peeling process and does not affect the performance of the device; and no residue is left after peeling, which does not affect the packaging of the flexible device.
[0035] (2) The materials used in this invention are simple, readily available, and inexpensive, and the bonding process is simple to operate; the flexible substrate bonded on the rigid substrate can ensure the flatness of the battery during the preparation process; and ensure that bubbling and deformation will not occur during the annealing process, thus affecting the preparation of the film layer.
[0036] (3) The present invention can peel the prepared flexible perovskite battery off the glass substrate without damage, leaving no residue, and the peeling process is simple and convenient; the rigid substrate can be reused, reducing costs. Attached Figure Description
[0037] Figure 1 and Figure 2 This is a schematic diagram illustrating the invention for a flexible substrate, a UV-resistant double-sided adhesive tape, and a rigid substrate.
[0038] Figure 3 This is a schematic diagram of the structure of the flexible perovskite solar cell described in this invention.
[0039] Figure 4 This is the performance curve of the flexible solar cell prepared by the method described in Embodiment 1 of the present invention. Detailed Implementation
[0040] To better illustrate the purpose, technical solution, and advantages of the present invention, the present invention will be further described below in conjunction with specific embodiments, but the scope of protection and implementation of the present invention are not limited thereto.
[0041] Unless otherwise specified, the materials and reagents used in the following examples are commercially available.
[0042] Example 1 A method for fabricating a flexible perovskite solar cell includes the following steps: (1) Prepare a clean and flat rigid substrate (3.2 mm thick), UV anti-adhesion double-sided tape (70 μm thick), and a flexible substrate (125 μm thick). For example... Figure 1As shown, the flexible substrate includes a flexible substrate and a conductive layer stacked together. Both surfaces of the UV anti-adhesion double-sided tape are provided with release protective films. The lower surface of the flexible substrate and the upper surface of the conductive layer are respectively provided with release protective films. In this embodiment, the rigid substrate is a rigid glass substrate, the flexible substrate is made of polyethylene terephthalate, the UV anti-adhesion tape is a commercially available product (model: UV5220), and the conductive layer is made of indium tin oxide.
[0043] (2) Remove the release film from one side of the UV anti-adhesion double-sided tape and press it flat onto the upper surface of the rigid glass substrate under pressure. Use rollers to press it firmly during the bonding process.
[0044] (3) Remove the release protective film from the other surface of the UV anti-adhesion double-sided tape and the release protective film from the lower surface of the flexible substrate, stick the UV anti-adhesion double-sided tape and the lower surface of the flexible substrate together, and use a roller to compact them.
[0045] (4) Remove the release protective film on the upper surface of the conductive layer to obtain a substrate that can be directly used to prepare perovskite solar cells. The substrate of the flexible perovskite solar cell obtained by this method can completely guarantee its flatness. Perform a first laser scribing on the upper surface (conductive layer) of the obtained perovskite solar cell substrate to remove the conductive layer. The first laser scribing is mainly to form several uniformly spaced first grooves on the flexible substrate. The width of the first groove is 30 μm and the depth is 400 nm.
[0046] (5) The first charge transport layer (thickness of 30 nm), the perovskite layer (thickness of 450 nm), and the second charge transport layer (thickness of 300 nm) are sequentially prepared from bottom to top on the upper surface of the substrate after the first laser scribing. The preparation process can be conventional spin coating, wire rod coating, or slot coating. There are no special restrictions on the preparation process, as long as the purpose of the present invention can be achieved. Before preparing the first charge transport layer, the upper surface of the substrate is surface treated by plasma with a power of 80 W and a time of 3 min.
[0047] (6) Perform a second laser scribing on the device prepared in step (5) to remove the second charge transport layer, the perovskite layer and the first charge transport layer, forming a number of second grooves; the second groove is located on one side of the first groove; the width of the second groove is 100 μm and the depth is 800 nm; the width between the first groove and the second groove is 50 μm.
[0048] (7) After the second laser scribing, a metal electrode layer is prepared on the surface of the second charge transport layer by magnetron sputtering. The metal electrode layer is a Cu electrode layer with a thickness of 80 nm.
[0049] (8) Perform a third laser scribing on the device prepared in step (7) to form several third grooves, remove the metal electrode layer, the second charge transport layer, the perovskite layer, and the first charge transport layer, and obtain a perovskite solar cell device with a rigid glass substrate; the third groove is located on one side of the second groove and the second groove is located between the first groove and the third groove, the width of the third groove is 30 μm, and the depth is 800 nm, as shown. Figure 3 As shown. The width between the second and third grooves is 40 μm.
[0050] (9) The perovskite solar cell device was irradiated with UV light at a wavelength of 365 nm, with an irradiation energy range of 500 mJ / cm. 2 .
[0051] (10) such as Figure 2 As shown, a flexible solar device is obtained by separating a flexible substrate and a rigid glass substrate.
[0052] Example 2 A method for fabricating a flexible perovskite solar cell includes the following steps: (1) Prepare a clean and flat rigid substrate (3.2 mm thick), UV anti-adhesion double-sided tape (70 μm thick), and a flexible substrate (188 μm thick). For example... Figure 1 As shown, the flexible substrate includes a flexible substrate and a conductive layer stacked together. Both surfaces of the UV anti-adhesion double-sided tape are provided with release protective films. The lower surface of the flexible substrate and the upper surface of the conductive layer are respectively provided with release protective films. In this embodiment, the rigid substrate is a rigid glass substrate, the flexible substrate is made of polyimide, the UV anti-adhesion tape is a commercially available product (model: UV5220), and the conductive layer is made of aluminum-doped zinc oxide.
[0053] (2) Remove the release film from one side of the UV anti-adhesion double-sided tape and apply it flat to the upper surface of the rigid glass substrate under specific pressure. Use rollers to press it firmly during the application process.
[0054] (3) Remove the release protective film from the other surface of the UV anti-adhesion double-sided tape and the release protective film from the lower surface of the flexible substrate, stick the UV anti-adhesion double-sided tape and the lower surface of the flexible substrate together, and use a roller to compact them.
[0055] (4) Remove the release protective film on the upper surface of the conductive layer to obtain a substrate that can be directly used to prepare perovskite solar cells. The substrate of the flexible perovskite solar cell obtained by this method can completely guarantee its flatness. Perform a first laser scribing on the upper surface (conductive layer) of the obtained perovskite solar cell substrate to remove the conductive layer. The first laser scribing is mainly to form several uniformly spaced first grooves on the flexible substrate. The width of the first groove is 40 μm and the depth is 300 nm.
[0056] (5) The first charge transport layer (thickness of 35nm), the perovskite layer (thickness of 500nm) and the second charge transport layer (thickness of 350nm) are sequentially prepared from bottom to top on the upper surface of the substrate after the first laser scribing. The preparation process can be spin coating, wire rod coating or slot coating. Before preparing the first charge transport layer, the upper surface of the substrate is surface treated by UV plasma cleaning. The UV plasma cleaning power is 20 W and the time is 10 min.
[0057] (6) Perform a second laser scribing on the device prepared in step (5) to remove the second charge transport layer, the perovskite layer and the first charge transport layer, forming a number of second grooves; the second groove is located on one side of the first groove; the width of the second groove is 150 μm and the depth is 900 nm; the width between the first groove and the second groove is 80 μm.
[0058] (7) After the second laser scribing, a metal electrode layer is prepared on the surface of the second charge transport layer by magnetron sputtering. The metal electrode layer is a Cu electrode layer with a thickness of 100 nm.
[0059] (8) Perform a third laser scribing on the device prepared in step (7) to form several third grooves, remove the metal electrode layer, the second charge transport layer, the perovskite layer, and the first charge transport layer, and obtain a perovskite solar cell device with a rigid glass substrate; the third groove is located on one side of the second groove and the second groove is located between the first groove and the third groove, the width of the third groove is 35 μm, and the depth is 900 nm, as shown. Figure 3 As shown. The width between the second and third grooves is 60 μm.
[0060] (9) The perovskite solar cell device was irradiated with UV light at a wavelength of 365 nm, with an irradiation energy range of 800 mJ / cm. 2 .
[0061] (10) such as Figure 2 As shown, a flexible solar device is obtained by separating a flexible substrate and a rigid glass substrate.
[0062] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit the scope of protection of the present invention. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the essence and scope of the technical solutions of the present invention.
Claims
1. A method for fabricating a flexible perovskite solar cell, characterized in that, Includes the following steps: (1) Obtain a rigid substrate, a flexible substrate and a UV anti-adhesion double-sided tape. The flexible substrate includes a flexible substrate and a conductive layer stacked together. Both surfaces of the UV anti-adhesion double-sided tape are provided with release protective films. The lower surface of the flexible substrate and the upper surface of the conductive layer are respectively provided with release protective films. (2) Remove the protective film from one surface of the UV anti-adhesion double-sided tape and attach the UV anti-adhesion double-sided tape to the upper surface of the rigid substrate; (3) Remove the protective film on the other side of the UV anti-adhesion double-sided tape and the protective film on the lower surface of the flexible substrate, and then attach the UV anti-adhesion double-sided tape to the lower surface of the flexible substrate. (4) Remove the protective film on the upper surface of the conductive layer, and then perform the first laser scribing on the flexible substrate to remove the conductive layer and form several uniformly spaced first grooves on the flexible substrate. (5) The first charge transport layer, the perovskite layer and the second charge transport layer are sequentially prepared from bottom to top on the upper surface of the substrate after the first laser scribing; (6) Perform a second laser scribing on the device prepared in step (5) to remove the second charge transport layer, the perovskite layer and the first charge transport layer, forming a number of second grooves; the second grooves are located on one side of the first groove; (7) After the second laser scribing, a metal electrode layer is prepared on the surface of the second charge transport layer; (8) Perform a third laser scribing on the device prepared in step (7) to form several third grooves, remove the metal electrode layer, the second charge transport layer, the perovskite layer and the first charge transport layer to obtain a perovskite solar energy device; the third groove is located on one side of the second groove and the second groove is located between the first groove and the third groove. (9) The perovskite solar cell device is irradiated with UV light of a specific wavelength, with an irradiation energy range of 300-800 mJ / cm. 2 The wavelength of the UV irradiation is 365 nm, 254 nm, or 395 nm. (10) Separate the flexible substrate and the rigid substrate to obtain a flexible perovskite solar cell.
2. The method for fabricating a flexible perovskite solar cell as described in claim 1, characterized in that, The flexible substrate in step (1) is made of at least one of polyethylene terephthalate, polyethylene naphthalate, and polyimide. And / or, the material of the conductive layer in step (1) includes at least one of indium tin oxide, fluorine-doped tin oxide, aluminum-doped zinc oxide, and gallium-doped zinc oxide.
3. The method for fabricating a flexible perovskite solar cell as described in claim 1, characterized in that, In step (2), the UV anti-adhesion double-sided tape and the rigid substrate are pressed together using rollers or scrapers during the bonding process.
4. The method for fabricating a flexible perovskite solar cell as described in claim 1, characterized in that, In step (4), the width of the first groove is 10-40 μm and the depth is 300-500 nm.
5. The method for fabricating a flexible perovskite solar cell as described in claim 1, characterized in that, The process for preparing the first charge transport layer, the perovskite layer and the second charge transport layer in step (5) includes spin coating, wire rod coating or slot coating. And / or, in step (5), the upper surface of the flexible substrate is surface treated before the first charge transport layer is prepared, and the surface treatment method includes plasma or UV plasma cleaning.
6. The method for fabricating a flexible perovskite solar cell as described in claim 5, characterized in that, The plasma has a power of 30-100 W and a duration of 1-5 min; Alternatively, the power of the UV plasma cleaning is 10-30 mW / cm. 2 The time is 5-15 minutes.
7. The method for fabricating a flexible perovskite solar cell as described in claim 1, characterized in that, In step (6), the width of the second groove is 80-150 μm and the depth is 700-900 nm; And / or, the width between the first groove and the second groove in step (6) is 30-80 μm.
8. The method for fabricating a flexible perovskite solar cell as described in claim 1, characterized in that, The width of the third groove in step (8) is 15-35 μm and the depth is 600-950 nm; And / or, the width between the second and third grooves in step (8) is 25-60 μm.
9. The method for fabricating a flexible perovskite solar cell as described in claim 1, characterized in that, In step (7), the metal electrode layer is prepared by thermal evaporation or magnetron sputtering. And / or, the metal electrode layer in step (7) includes an Au electrode layer, an Ag electrode layer, or a Cu electrode layer.
10. A flexible perovskite solar cell, prepared by the method for preparing a flexible perovskite solar cell according to any one of claims 1-9.