Photo-repair perovskite photoelectric device and performance repair method thereof

Abstract

The invention belongs to the field of photovoltaic technology, and particularly relates to a photo-repairing type perovskite photoelectric device and a performance repairing method thereof. The light repair type perovskite photoelectric device comprises a transparent conductive substrate, an electron transport layer, a perovskite light absorption layer, a hole transport layer and a metal electrode which are in contact in sequence, and light response type passivation molecules are contained at the interface of the perovskite light absorption layer and an adjacent functional layer or in the perovskite light absorption layer. The light response type passivation molecules can release repairing groups combined with defect sites in the perovskite light absorption layer when illuminated by a certain wavelength and / or intensity. According to the perovskite photoelectric device provided by the invention, in-situ dynamic passivation repair can be carried out on defects generated in operation of the perovskite photoelectric device under a specific illumination condition, and the effective service life of the perovskite photoelectric device is remarkably prolonged.

Description

Technical Field

[0001] This invention belongs to the field of photovoltaic technology, and in particular relates to a photo-repairable perovskite optoelectronic device and a method for repairing its performance. Background Technology

[0002] Organic-inorganic hybrid perovskite solar cells, representing the next generation of thin-film photovoltaic technology, have made remarkable progress over the past decade, with laboratory-certified photoelectric conversion efficiencies exceeding 26%, comparable to some commercially available crystalline silicon cells. However, compared to the 25-year or more lifespan promised by traditional photovoltaic technologies, the operational stability of perovskite devices is the most severe challenge they face in moving towards large-scale commercialization.

[0003] Ultimately, perovskite materials are a typical "soft semiconductor." Their ionic crystal properties make their chemical structure and microstructure prone to change under the combined effects of continuous illumination, electric fields, oxygen, water vapor, and their own thermal effects. Specifically: 1) Illumination, especially ultraviolet light, can induce iodine ion migration and even precipitation, forming highly reactive iodine vacancies; 2) Under electric field stress, ion migration is significant, leading not only to interfacial energy level mismatch and intensified interfacial recombination, but also to irreversible chemical reactions at the electrodes; 3) Uncoordinated lead ions, acting as deep-level defect centers, become non-radiative recombination channels for charge carriers, significantly reducing the device's open-circuit voltage and fill factor. The generation and proliferation of these defects is a dynamic and continuous process, ultimately leading to irreversible degradation of the device's photoelectric performance.

[0004] To address the aforementioned stability issues, existing technologies primarily focus on "prevention" and "delay" strategies. For example, composition engineering (such as mixing cations or halogens) is used to improve lattice formation energy; additive engineering (introducing polymers, fullerenes, etc.) is used to pre-passivate bulk defects during film formation; and interface engineering (introducing ultrathin insulating layers, novel organic molecules, etc.) is used to block ion migration and reduce interfacial recombination. While these methods improve the initial efficiency and short-term stability of devices to some extent, they are essentially "one-off" or "static" passivation. Once new defects develop during long-term operation, or the original passivation layer fails due to aging, existing technologies become ineffective, and the performance degradation process becomes irreversible. This means that once the device's performance degrades to a certain critical point, the entire device reaches the end of its lifespan and must be scrapped. This not only limits its commercial application prospects but also leads to resource waste and potential environmental problems.

[0005] Therefore, there is an urgent need in this field for an innovative technology that can overcome the limitations of existing "static defense" and can "repair" defects that are dynamically generated during the service life of a device in real time or periodically, thereby achieving in-situ regeneration of device performance and fundamentally extending its effective service life. Summary of the Invention

[0006] In view of this, the purpose of the present invention is to provide a photo-repairable perovskite optoelectronic device and a method for repairing its performance. The perovskite optoelectronic device provided by the present invention can perform in-situ dynamic passivation repair on defects generated during operation under specific illumination conditions, which can significantly extend the effective service life of the perovskite optoelectronic device.

[0007] This invention provides a photo-repairing perovskite optoelectronic device, comprising a transparent conductive substrate, an electron transport layer, a perovskite light-absorbing layer, a hole transport layer, and a metal electrode in sequential contact. The perovskite light-absorbing layer contains photoresponsive passivation molecules at the interface between the perovskite light-absorbing layer and the adjacent functional layer or within the perovskite light-absorbing layer. When exposed to light of a certain wavelength and / or intensity, the photoresponsive passivation molecules can release repair groups that bind to defect sites in the perovskite light-absorbing layer.

[0008] Preferably, the photoresponsive passivation molecule comprises a photosensitive group and a passivation group; the photosensitive group is one or more selected from azophenyl, spiropyranyl, nitrobenzyl ester, and coumarin ester; the passivation group is capable of reacting with uncoordinated Pb in the perovskite light-absorbing layer. 2+ One or more of the following groups are combined: halogen vacancies and organic cation vacancies.

[0009] Preferably, the passivating group is one or more of carboxyl, phosphonic, sulfonic, amino, amide, pyridyl, thioether, and crown ether groups.

[0010] Preferably, the photoresponsive passivating molecule is one or more selected from 4-nitro-3-methoxycarbonylbenzoic acid, methyl 2-amino-4-phenylthiophene-3-carboxylate, diphenyliodonitrate, acetylferrocene, 2-[(diphenylmethyl)mercapto]acetic acid, monomethyl 2-nitroterephthalate, 4-methoxy-3,5-dinitrobenzoic acid, and (4-methoxyphenyl)methyl-3,5-dinitrobenzoic acid ester.

[0011] Preferably, the adjacent functional layer is a hole transport layer.

[0012] Preferably, the light source is ultraviolet light.

[0013] Preferably, the wavelength of the light is 200~400nm and the intensity is 1~100mW / cm. 2 .

[0014] This invention provides a method for performance restoration of photo-repairable perovskite optoelectronic devices, comprising the following steps:

[0015] The performance parameters of the photo-repairable perovskite optoelectronic device described in the above technical solution are monitored. When the performance parameters decay to a preset threshold, light of a certain wavelength and / or intensity is applied to the photo-repairable perovskite optoelectronic device, causing the photoresponsive passivation molecules to release repair groups that can bind to defect sites in the perovskite light absorption layer, thereby restoring the device performance.

[0016] Preferably, the performance parameter is one or more of photoelectric conversion efficiency, open-circuit voltage, short-circuit current, and fill factor; the preset threshold is 70-90% of the initial value of the performance parameter.

[0017] Preferably, the illumination time is 10s to 30min.

[0018] Compared with existing technologies, this invention provides a photo-repairable perovskite optoelectronic device and its performance repair method. The photo-repairable perovskite optoelectronic device provided by this invention includes a transparent conductive substrate, an electron transport layer, a perovskite light-absorbing layer, a hole transport layer, and a metal electrode in sequential contact. The perovskite light-absorbing layer contains photoresponsive passivation molecules at the interface with adjacent functional layers or within the perovskite light-absorbing layer. These photoresponsive passivation molecules, when exposed to light of a certain wavelength and / or intensity, can release repair groups that bind to defect sites in the perovskite light-absorbing layer. This invention, by pre-positioning photoresponsive passivation molecules as "repair seeds" within the perovskite optoelectronic device, can trigger the release of active groups under specific lighting conditions, achieving in-situ dynamic passivation repair of defects generated in the operating perovskite optoelectronic device. This upgrades the stability strategy from passive protection to active regeneration, ultimately significantly extending the effective service life of the perovskite optoelectronic device and overcoming the core bottleneck of its long-term operational stability. Attached Figure Description

[0019] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, 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 embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0020] Figure 1 JV curves of the perovskite optoelectronic devices of Example 1 and Comparative Example 1 after 500 hours of operation, provided by the present invention;

[0021] Figure 2 JV curves of the perovskite optoelectronic devices of Embodiment 1 and Comparative Example 1 after one optical repair provided by the present invention;

[0022] Figure 3 This is a graph showing the change of PCE over time during the cyclic optical repair process of the perovskite optoelectronic devices of Embodiment 1 and Comparative Example 1 provided by the present invention. Detailed Implementation

[0023] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0024] This invention provides a photo-repairable perovskite optoelectronic device, comprising a transparent conductive substrate, an electron transport layer, a perovskite light-absorbing layer, a hole transport layer, and a metal electrode in sequential contact; the perovskite light-absorbing layer contains photoresponsive passivation molecules at the interface with the adjacent functional layer or within the perovskite light-absorbing layer; the photoresponsive passivation molecules can undergo photolysis or photoisomerization reactions when exposed to light of a certain wavelength and / or intensity, changing their molecular structure and releasing repair groups that can bind to defect sites in the perovskite light-absorbing layer, thereby achieving in-situ passivation repair of defects in the bulk phase and at the interface of the perovskite light-absorbing layer.

[0025] In the photo-repairing perovskite optoelectronic device provided by the present invention, the photoresponsive passivation molecule preferably comprises a photosensitive group and a passivation group; wherein, the photosensitive group is preferably one or more selected from azophenyl, spiropyranyl, nitrobenzyl ester, and coumarin ester; and the passivation group is preferably capable of reacting with uncoordinated Pb in the perovskite light-absorbing layer. 2+ One or more of the following groups are combined: halogen vacancies and organic cation vacancies, specifically one or more of the following groups: carboxyl, phosphonic acid, sulfonic acid, amino, amide, pyridyl, thioether, and crown ether.

[0026] In the photo-repairing perovskite optoelectronic device provided by the present invention, the photoresponsive passivation molecule may be selected from one or more of the following: 4-nitro-3-methoxycarbonylbenzoic acid (CAS: 64152-09-6), methyl 2-amino-4-phenylthiophene-3-carboxylate (CAS: 112440-47-8), diphenyliodonitrate (CAS: 722-56-5), acetylferrocene (CAS: 1271-55-2), 2-[(diphenylmethyl)mercapto]acetic acid (CAS: 63547-22-8), monomethyl 2-nitroterephthalate (CAS: 35092-89-8), 4-methoxy-3,5-dinitrobenzoic acid (CAS: 85365-92-0), and (4-methoxyphenyl)methyl-3,5-dinitrobenzoate (CAS: 93141-01-6).

[0027] In the photo-repair perovskite optoelectronic device provided by the present invention, the photoresponsive passivation molecule can undergo photolysis or photoisomerization reaction when exposed to light of a certain wavelength and / or intensity, thereby breaking the chemical bond between the passivation group and the photosensitive group in the photoresponsive passivation molecule or changing the molecular configuration, thus exposing the passivation group.

[0028] In the photo-repair perovskite optoelectronic device provided by the present invention, the photoresponsive passivation molecules are distributed at the interface between the perovskite light absorption layer and the adjacent functional layer or within the perovskite light absorption layer, wherein the adjacent functional layer is preferably a hole transport layer.

[0029] In the photo-repair perovskite optoelectronic device provided by this invention, the light source for illumination is preferably ultraviolet light; the wavelength of the illumination is preferably 200~400nm, specifically 200nm, 210nm, 220nm, 230nm, 240nm, 250nm, 260nm, 270nm, 280nm, 290nm, 300nm, 310nm, 320nm, 330nm, 340nm, 350nm, 360nm, 365nm, 370nm, 380nm, 390nm, or 400nm; the intensity of the illumination is preferably 1~100mW / cm². 2 Specifically, it can be 1mW / cm 2 5mW / cm 2 10mW / cm 2 15mW / cm 2 20mW / cm 2 25mW / cm 2 30mW / cm 2 35mW / cm 2 40mW / cm 2 45mW / cm 2 50mW / cm2 60mW / cm 2 70mW / cm 2 80mW / cm 2 90mW / cm 2 Or 100mW / cm 2 .

[0030] In the photo-repairing perovskite optoelectronic device provided by the present invention, the photoresponsive passivation molecule can be introduced into the photo-repairing perovskite optoelectronic device through at least one of the following methods:

[0031] Method 1 (Interface Modification): After the perovskite light absorption layer is deposited and before the hole transport layer is prepared, a solution containing photoresponsive passivation molecules is coated on the surface of the perovskite light absorption layer to form a photoresponsive passivation molecule modification layer.

[0032] Method 2 (bulk doping): When preparing the perovskite light absorption layer or hole transport layer, a precursor solution containing photoresponsive passivation molecules is used for coating, so that the photoresponsive passivation molecules are uniformly distributed in the perovskite light absorption layer or hole transport layer.

[0033] Method 3 (Pre-embedded introduction): During the crystallization process of preparing the perovskite light-absorbing layer, an antisolvent containing photoresponsive passivating molecules is used, thereby anchoring the photoresponsive passivating molecules to the perovskite grain boundaries.

[0034] This invention also provides a method for performance restoration of photo-repairable perovskite optoelectronic devices, comprising the following steps:

[0035] The performance parameters of the photo-repairable perovskite optoelectronic device described in the above technical solution are monitored. When the performance parameters decay to a preset threshold, light of a certain wavelength and / or intensity is applied to the photo-repairable perovskite optoelectronic device, causing the photoresponsive passivation molecules to release repair groups that can bind to defect sites in the perovskite light absorption layer, thereby restoring the device performance.

[0036] In the performance repair method provided by the present invention, the performance parameter is preferably one or more of photoelectric conversion efficiency (PCE), open circuit voltage (Voc), short circuit current (Jsc), and fill factor (FF); the preset threshold is preferably 70-90% of the initial value of the performance parameter.

[0037] In the performance restoration method provided by this invention, the light source of the illumination is preferably ultraviolet light; the wavelength of the illumination is preferably 200~400nm, specifically 200nm, 210nm, 220nm, 230nm, 240nm, 250nm, 260nm, 270nm, 280nm, 290nm, 300nm, 310nm, 320nm, 330nm, 340nm, 350nm, 360nm, 365nm, 370nm, 380nm, 390nm, or 400nm; the intensity of the illumination is preferably 1~100mW / cm². 2 Specifically, it can be 1mW / cm 2 5mW / cm 2 10mW / cm 2 15mW / cm 2 20mW / cm 2 25mW / cm 2 30mW / cm 2 35mW / cm 2 40mW / cm 2 45mW / cm 2 50mW / cm 2 60mW / cm 2 70mW / cm 2 80mW / cm 2 90mW / cm 2 Or 100mW / cm 2 The preferred illumination time is 10s to 30min, specifically 10s, 20s, 30s, 1min, 2min, 3min, 4min, 5min, 7min, 10min, 12min, 15min, 17min, 20min, 23min, 25min, 27min or 30min.

[0038] In the performance repair method provided by the present invention, the performance of the optically repairable perovskite optoelectronic device can be repeatedly repaired multiple times. When the performance parameters of the optically repairable perovskite optoelectronic device decay to the preset threshold or another preset threshold, the above performance repair steps can be repeated.

[0039] The technical solution provided by this invention can achieve in-situ and controllable repair of the performance of perovskite optoelectronic devices. Specifically, as verified by experiments, for a device with an initial efficiency of 23.5%, after the efficiency decays to 19.3% after 500 hours of continuous operation, a single application of a specific wavelength (365nm) and intensity (20mW / cm²) can restore the performance of the device. 2After 5 minutes of ultraviolet light irradiation, the efficiency of the device can be significantly restored to 22.8%, a recovery of 3.5 percentage points. This repair process can be repeated multiple times, increasing the effective lifespan of the device by more than three times. This repair mechanism can precisely target and passivate newly generated deep-level defects during operation, especially significantly restoring the open-circuit voltage and fill factor. At the same time, the entire repair process does not require disassembling the device or introducing additional chemical substances, only simple light irradiation. It is easy to operate and extremely low in cost, providing a breakthrough solution for the long-term stable operation and commercial application of perovskite optoelectronic devices.

[0040] For clarity, the following examples and comparative models will be used to provide a detailed description.

[0041] Example 1

[0042] The fabrication and repair process of a photo-repairable perovskite optoelectronic device based on hole transport layer doping specifically includes:

[0043] Step 1: Substrate pretreatment and electron transport layer deposition

[0044] Take FTO conductive glass (FTO thickness 200~500nm, glass thickness 2.2mm), and place it in deionized water, anhydrous ethanol and isopropanol for ultrasonic cleaning for 15min respectively. Then, blow dry the surface with dry compressed air. Subsequently, deposit a dense TiO2 film on its surface as an electron transport layer.

[0045] Step 2: Preparation of perovskite precursor solution

[0046] Accurately weigh 207.3 mg of lead iodide (PbI2, 99.99%), 72.3 mg of formamidinium iodide (FAI, 99.5%), and 6.9 mg of cesium chloride (CsCl, 99.9%), and place them in a 2 mL sample vial. Add 278 μL of a mixture of anhydrous DMSO and 722 μL of anhydrous DMF to the vial. Seal the sample vial and place it on a 60 °C hot plate. Stir at 800 rpm for 6 h to obtain a clear and transparent perovskite precursor solution.

[0047] Step 3: Preparation of photoresponsive passivation molecular solution

[0048] Accurately weigh 5.0 mg of 4-nitro-3-methoxycarbonylbenzoic acid (CAS: 64152-09-6), dissolve it in 10 mL of anhydrous chlorobenzene, and place it in a 20 mL brown sample bottle; stir at 500 rpm for 12 h at room temperature in the dark to obtain a photoresponsive passivation molecular solution with a concentration of 0.5 mg / mL.

[0049] Step 4: Preparation of hole transport layer precursor solution

[0050] Weigh 72.3 mg Spiro-OMeTAD, add 28.8 μL Li-TFSI acetonitrile solution (520 mg / mL) and 17.5 μL 4-tert-butylpyridine; then add 1.0 mL of the photoresponsive passivation molecular solution prepared in step 3, and stir at 300 rpm for 4 h under light-protected conditions to obtain the hole transport layer precursor solution.

[0051] Step 5: Thin Film Deposition and Device Assembly

[0052] The perovskite precursor solution prepared in the second step was spin-coated onto the TiO2 / FTO substrate prepared in the first step at 4000 rpm for 30 s. At the 15th s mark of spin-coating, 100 μL of anhydrous chlorobenzene was added as an antisolvent to form a perovskite light-absorbing layer. The substrate was then annealed on a hot stage at 100 °C for 30 min and cooled. The hole transport layer precursor solution prepared in the fourth step was spin-coated onto the cooled perovskite light-absorbing layer at 4000 rpm for 30 s to form a hole transport layer (doped with photoresponsive passivation molecules). Finally, an 80 nm gold electrode was deposited on the hole transport layer by thermal evaporation to complete the fabrication of the photo-repair perovskite optoelectronic device.

[0053] Comparative Example 1

[0054] The perovskite optoelectronic device is prepared according to Example 1, except that 4-nitro-3-methoxycarbonylbenzoic acid is not added to the solution prepared in the third step, that is, the photoresponsive passivation molecule is not introduced into the device.

[0055] Performance evaluation of the devices in Example 1 and Comparative Example 1:

[0056] (1) Performance Repair Verification

[0057] ① Initial performance test:

[0058] Using the device prepared in Example 1 as the target group and the device prepared in Comparative Example 1 as the control group, the two freshly prepared devices were tested under a standard solar simulator (AM 1.5G). The results were as follows: for the control group device, the initial photoelectric conversion efficiency (PCE) was 23.9%, the open-circuit voltage (Voc) was 1.173V, and the short-circuit current density (Jsc) was 25.58mA / cm². 2 The fill factor (FF) is 79.65%; for the target group of devices, the initial power conversion efficiency (PCE) is 24.7%, the open-circuit voltage (Voc) is 1.185V, and the short-circuit current density (Jsc) is 25.64mA / cm². 2The fill factor (FF) is 81.3%. The comparison shows that the device with the introduced photoresponsive passivation molecules significantly outperforms the device without them in key performance parameters such as initial photoelectric conversion efficiency, open-circuit voltage, short-circuit current density, and fill factor. This indicates that the addition of photoresponsive passivation molecules not only did not negatively impact device performance, but also further optimized the performance of the perovskite device by effectively passivating initial defects.

[0059] ②Accelerated aging and pre-repair testing:

[0060] The target and control group devices were subjected to accelerated aging tests by continuous operation at maximum power for 500 hours in a nitrogen atmosphere. The results are as follows: Figure 1 As shown in Table 1:

[0061] Table 1. Voc, Jsc, FF, and PCE of the device after accelerated aging

[0062]

[0063] pass Figure 1 As shown in Table 1, after 500 hours of continuous operation, the JV curve of the control group device exhibited severe performance degradation. Its photoelectric conversion efficiency (PCE) dropped significantly from the initial 23.9% to 16.71%, the open-circuit voltage (Voc) decreased from 1.173V to 1.109V, and the short-circuit current density (Jsc) decreased from 25.58mA / cm². 2 It dropped to 24.28 mA / cm 2 The fill factor (FF) significantly deteriorated from 79.65% to 63.01%. This indicates that, in conventional devices without photoresponsive passivation molecules, a large number of defect states accumulate inside and at the interface of the perovskite layer during long-term operation, leading to intensified nonradiative recombination of charge carriers and irreversible performance degradation. In contrast, the target group of devices exhibited significantly better stability under the same aging conditions, with its PCE decreasing from an initial 24.7% to 21.7%, open-circuit voltage (Voc) remaining at 1.178V, and short-circuit current density (Jsc) at 24.67 mA / cm². 2 The fill factor (FF) remained at 74.69%. Although the target group devices also experienced some performance degradation, the degradation of each parameter was significantly smaller than that of the control group. In particular, the retention rate of the fill factor (FF) was much higher than that of the control group, which fully demonstrates that the introduced photoresponsive passivation molecules continue to play a defect suppression role during long-term operation and effectively delay the proliferation of defects in the perovskite layer and interface.

[0064] ③ Photorejuvenation treatment:

[0065] The target and control group devices with performance degradation were removed from the test fixture and placed under an intensity of 20 mW / cm². 2 Irradiation was performed for 5 minutes at a vertical distance of 10 cm under a 365nm ultraviolet LED lamp; the entire process was carried out in an ambient temperature environment.

[0066] ④ Post-repair testing:

[0067] After the target and control group devices underwent photorepair treatment, their performance was immediately retested, and the results were as follows: Figure 2 As shown in Table 2:

[0068] Table 2. Voc, Jsc, FF, and PCE of the repaired device

[0069]

[0070] pass Figure 2 As shown in Table 2, the JV curves of the two groups of devices exhibit drastically different trends after repair. The control group device (without the introduction of photoresponsive passivation molecules) showed further performance deterioration after UV irradiation. Its photoelectric conversion efficiency (PCE) decreased from 16.71% after aging to 13.02%, its open-circuit voltage (Voc) decreased from 1.109V to 1.076V, and its short-circuit current density (Jsc) decreased from 24.28 mA / cm². 2 It dropped to 23.90 mA / cm 2 The fill factor (FF) dropped significantly from 63.01% to 49.97%. This indicates that, due to the lack of photoresponsive passivation molecules within the control group devices, UV irradiation not only failed to repair the defects but also exacerbated the degradation of the perovskite film, leading to a continuous decline in device performance. In contrast, the target group devices (introducing photoresponsive passivation molecules) showed significant performance recovery after the same UV irradiation treatment. Their PCE increased from 21.7% after aging to 23.22%, a 1.5 percentage point improvement compared to before repair, reaching 94% of the initial efficiency (24.7%). The open-circuit voltage (Voc) almost completely recovered to its initial level; and the short-circuit current density (Jsc) increased from 24.67 mA / cm². 2 It recovered to 24.55 mA / cm 2 The fill factor (FF) significantly improved from 74.69% to 80.46%, which is very close to the initial value of 81.3%. This recovery effect fully demonstrates that the photoresponsive passivation molecules pre-placed at the hole transport layer and perovskite interface successfully released active repair groups under ultraviolet light triggering, dynamically passivating and repairing newly generated interface and perovskite internal defects during operation, thereby effectively reversing the device performance degradation trend.

[0071] The test results after photorepair clearly show that the target group devices with photoresponsive passivation molecules can achieve in-situ dynamic repair of defects through ultraviolet light irradiation of a specific wavelength, significantly restoring key performance parameters, especially the fill factor, and achieving an efficiency of over 94% of the initial value after repair. In contrast, the control group devices without photoresponsive passivation molecules experienced further performance deterioration due to ultraviolet light-induced degradation under the same illumination conditions. This fully verifies the effectiveness and superiority of the photorepair strategy proposed in this invention.

[0072] (2) Circular application verification

[0073] Using the device prepared in Example 1 as the target group and the device prepared in Comparative Example 1 as the control group, the two groups of devices underwent two complete "operation-degradation-repair" cycles. Their PCE changes are as follows: Figure 3 As shown. (Through) Figure 3 As can be seen, the target group of devices (introducing photoresponsive passivation molecules) exhibits excellent repairability in both cycles: in each cycle, when the PCE decays to below 85% of its initial value after continuous operation, a single UV light repair treatment can restore the efficiency to over 95% of its initial value. Specifically, the initial efficiency in the first cycle was 24.7%, decayed to 21.0% after operation, and recovered to 23.7% after repair; in the second cycle, the efficiency decayed to 19.8% after operation, and recovered to 22.4% after repair. After a cumulative operating time of over 3000 hours, the final efficiency of the target group of devices still remained above 82% of its initial value, demonstrating excellent cyclic repair capability. In contrast, the control group device (without photoresponsive passivation molecules) exhibited irreversible performance degradation in the first operating cycle: the initial efficiency was 23.9%, which decreased to 16.7% after 500 hours of operation. Although UV light treatment was applied at this point, the lack of photoresponsive passivation molecules inside the device not only failed to restore performance, but also caused the efficiency to drop further to 13.02% due to UV-induced degradation. The fill factor deteriorated severely, making it unable to enter the second effective cycle, and its effective lifespan was only about 500 hours.

[0074] Cyclic application verification results show that the target group devices, through pre-placed photoresponsive passivation molecules, can achieve in-situ dynamic performance regeneration during multiple operation-degradation-repair cycles, with an effective lifespan more than three times that of the control group devices. In contrast, the control group devices, lacking a repair mechanism, cannot reverse performance degradation after the initial degradation and ultimately fail rapidly. This result fully demonstrates that the photorepair strategy proposed in this invention can overcome the "one-time use" lifespan bottleneck of traditional perovskite optoelectronic devices, providing a practical and feasible technical path for significantly extending device service life.

[0075] Example 2

[0076] The photo-repair perovskite optoelectronic device based on bulk phase doping of the perovskite light-absorbing layer is prepared according to Example 1, except that: 1.5 mg of 4-nitro-3-methoxycarbonylbenzoic acid is added in the perovskite precursor solution preparation step; and no photoresponsive passivation molecule solution is added in the hole transport layer precursor solution preparation step.

[0077] Following the evaluation method for the device in Example 1, the performance of the device prepared in Example 2 was verified through performance repair. The results showed that the initial photoelectric conversion efficiency of the device in Example 2 (24.3%) was basically the same as that in Example 1 (24.7%), indicating that bulk doping had no significant negative impact on the initial performance of the device. Under the same accelerated aging conditions (after 500 hours of continuous operation), due to the lack of synergistic effect of repair molecules at the hole transport layer interface, the efficiency of the device in Example 2 decreased to 20.8%, slightly lower than that of Example 1 (21.7%), showing slightly inferior stability. After the same ultraviolet light repair treatment, the efficiency of the device in Example 2 significantly recovered to 22.5%, with a repair margin of 1.7 percentage points, indicating that the repair molecules in bulk doping can also effectively passivate the newly formed defects inside the perovskite.

[0078] Example 3

[0079] The photo-repairable perovskite optoelectronic device based on the surface modification of the perovskite light absorption layer is prepared and repaired according to Example 1, except that: after the perovskite light absorption layer is prepared and annealed, the photoresponsive passivation molecular solution prepared in the third step is spin-coated on its surface at 4000 rpm for 30 s, and then heat-treated at 70°C for 10 min to anchor the molecules; the photoresponsive passivation molecular solution is not added in the hole transport layer precursor solution preparation step.

[0080] Following the evaluation method for the device in Example 1, the performance of the device prepared in Example 3 was verified through performance repair. The results showed that the initial photoelectric conversion efficiency of the device in Example 3 was 24.0%, slightly lower than that of Example 1 (24.7%) and Example 2 (24.3%), indicating that simple interface modification not only improved the interface charge transport performance but also effectively passivated defects at the interface. Under the same accelerated aging conditions (after 500 hours of continuous operation), its efficiency decreased to 19.5%, a significantly greater decrease than that of Example 1 (21.7%) and Example 2 (20.8%), indicating relatively poor stability. This is mainly attributed to the lack of repair molecules within the bulk phase, which cannot suppress the proliferation of perovskite bulk defects during operation. Under the same conditions (365 nm, 20 mW / cm²), the efficiency was further improved. 2After photorepair treatment (5 minutes of UV irradiation), the device efficiency recovered to 20.9%, a recovery of 1.4 percentage points, which is lower than that of Example 1 (1.5 percentage points to 23.22%) and Example 2 (1.7 percentage points to 22.5%). This indicates that the photoresponsive molecules at the interface can only passivate newly formed defects near the interface and have limited ability to repair deep-level defects in the bulk phase. Therefore, the recovery of open-circuit voltage and fill factor is not as good as the former two. However, compared with the control group that did not add any photoresponsive molecules (whose efficiency usually decays to below 15% after the same aging and cannot be repaired), this example still shows a certain degree of repairability, confirming that the interface modification strategy still has a positive effect on extending the device's service life.

[0081] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A photo-repairing perovskite optoelectronic device, comprising a transparent conductive substrate, an electron transport layer, a perovskite light-absorbing layer, a hole transport layer, and a metal electrode in sequential contact, characterized in that, The perovskite light-absorbing layer contains photoresponsive passivation molecules at the interface between it and the adjacent functional layer or within the perovskite light-absorbing layer. When exposed to light of a certain wavelength and / or intensity, these photoresponsive passivation molecules can release repair groups that bind to defect sites in the perovskite light-absorbing layer.

2. The photo-repair perovskite optoelectronic device according to claim 1, characterized in that, The photoresponsive passivation molecule comprises a photosensitive group and a passivation group; the photosensitive group is one or more selected from azophenyl, spiropyranyl, nitrobenzyl ester, and coumarin ester; the passivation group is capable of reacting with uncoordinated Pb in the perovskite light-absorbing layer. 2+ One or more of the following groups are combined: halogen vacancies and organic cation vacancies.

3. The photo-repairing perovskite optoelectronic device according to claim 2, characterized in that, The passivating group is one or more of the following: carboxyl, phosphonic, sulfonic, amino, amide, pyridyl, thioether, and crown ether.

4. The photo-repair perovskite optoelectronic device according to claim 1, characterized in that, The photoresponsive passivating molecule is one or more of the following: 4-nitro-3-methoxycarbonylbenzoic acid, methyl 2-amino-4-phenylthiophene-3-carboxylate, diphenyliodonitrate, acetylferrocene, 2-[(diphenylmethyl)mercapto]acetic acid, monomethyl 2-nitroterephthalate, 4-methoxy-3,5-dinitrobenzoic acid, and (4-methoxyphenyl)methyl-3,5-dinitrobenzoate.

5. The photo-repair perovskite optoelectronic device according to claim 1, characterized in that, The adjacent functional layer is a hole transport layer.

6. The photo-repairing perovskite optoelectronic device according to claim 1, characterized in that, The light source is ultraviolet light.

7. The photo-repairing perovskite optoelectronic device according to claim 1, characterized in that, The wavelength of the illumination is 200~400nm, and the intensity is 1~100mW / cm. 2 .

8. A method for performance restoration of a photo-repairable perovskite optoelectronic device, characterized in that, Includes the following steps: Monitor the performance parameters of the photo-repairable perovskite optoelectronic device according to any one of claims 1 to 7. When the performance parameters decay to a preset threshold, apply light of a certain wavelength and / or intensity to the photo-repairable perovskite optoelectronic device to cause the photoresponsive passivation molecules to release repair groups that can bind to defect sites in the perovskite light absorption layer, thereby restoring the device performance.

9. The performance repair method according to claim 8, characterized in that, The performance parameters are one or more of photoelectric conversion efficiency, open-circuit voltage, short-circuit current, and fill factor; the preset threshold is 70-90% of the initial value of the performance parameters.

10. The performance repair method according to claim 8, characterized in that, The illumination time is 10s to 30min.

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