A perovskite film layer passivator and a preparation method and application thereof

Abstract

The application provides a perovskite film layer passivator, a preparation method and application thereof, and the perovskite film layer passivator is a triphenylmethyl carbon radical. The perovskite film layer passivator is selected from a triphenylmethyl carbon radical, so that the surface / bulk defects of perovskite crystals can be reduced, and the photoelectric conversion efficiency and service life of a perovskite photovoltaic device can be improved.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of photovoltaic solar cells, and relates to a perovskite film layer passivation agent and a preparation method and application thereof. BACKGROUND

[0002] In recent years, perovskite photovoltaic solar cells have developed rapidly. The highest photoelectric conversion efficiency of a single-junction photovoltaic cell based on an organic-inorganic hybrid perovskite material has reached 25.7%, and the theoretical upper limit thereof is higher than that of a traditional crystalline silicon cell. In the future, the perovskite material is expected to replace crystalline silicon and become a new generation of photovoltaic material. However, due to the ionic crystal characteristics of the perovskite material, uncoordinated metal cations, organic amine cations, halide anion vacancies and other defects are inevitably formed in the preparation process, which greatly affects the efficiency and service life of the prepared perovskite device. Therefore, defect passivation of the perovskite is an essential link in the device preparation process.

[0003] At present, the passivation technology for the perovskite film layer can be divided into two categories according to the distribution of the passivation agent. One category is to add the passivation agent when the perovskite precursor solution is configured, and the passivation agent is distributed in the entire perovskite crystal. The other category is to form a passivation layer between the perovskite film layer and the transport layer material, which plays a surface modification role. The second category of passivation agent is usually used only between the perovskite and the second transport layer (ETL of formal structure or HTL of reverse structure), but the performance of the device produced by such passivation technology still needs to be further improved.

[0004] Common passivators include: ① Lewis base materials containing O, S, P, N, Cl, etc. electron-rich groups, which can interact with metal cations with Lewis acidity to play a passivation role; ② Long-chain organic ammonium salt compounds can convert part of the three-dimensional perovskite into two-dimensional / quasi-two-dimensional low-dimensional perovskite, playing a role in defect passivation and carrier extraction; ③ Other kinds of passivators. Most of the common passivators currently used are neutral organic small molecules or corresponding organic amine salts. Organic radical molecules, due to their unique single electron, have been proven to be applied in organic electroluminescent devices (OLED) to achieve excellent optoelectronic performance (Nature 2018, 563, 536-540). Similarly, the unique excellent optoelectronic performance of organic radicals can also be applied to the field of perovskite photovoltaics, but most of the related work is still focused on nitrogen or nitroxide radicals (Chem. Res. Chin. Univ. 2023, 39, 176-186; Frontiers in Chemistry 2020, 8, 10.3389 / fchem.2020.00825), only a small amount of work has studied the application of stable carbon radicals in perovskite photovoltaics, and only used in the anti-solvent of spin-coating method for preparing small-area devices (Chemical Engineering Journal 2023, 462, 142328). Commercial large-area perovskite photovoltaic modules cannot be prepared by spin-coating method, and anti-solvent method cannot be used to control perovskite crystallization due to environmental protection and cost considerations. On the other hand, the triphenylmethyl carbon radical in the carbon radical has excellent stability while retaining the unique optoelectronic properties of the single electron of the radical, and the peripheral aromatic group can be modified in many ways, making it a highly potential perovskite passivation material. Therefore, in the field, it is desirable to develop a triphenylmethyl carbon radical passivator that can be further improved and can be applied to solution method for preparing large-area perovskite solar cells. SUMMARY

[0005] In view of the deficiencies of the prior art, the purpose of the present application is to provide a perovskite film layer passivator and its preparation method and application.

[0006] To achieve this application purpose, the application adopts the following technical solutions:

[0007] On the one hand, the present application provides a perovskite film layer passivator, which is a triphenylmethyl carbon radical, having the following formula I or formula II structure:

[0008]

[0009]

[0010] wherein R is independently selected from aryl / alkyl amine groups aryl / alkyl phosphine groups alkoxy (-OR1), alkylthiol (-SR1), amido (-NH-CO-R2), substituted or unsubstituted C6-C22 aryl, or substituted or unsubstituted C5-C20 heteroaryl, wherein R1 is selected from a C1-C6 long chain alkyl chain, substituted or unsubstituted C6-C22 aromatic group, substituted or unsubstituted C5-C20 heteroaryl group, and R2 is selected from a C1-C6 long chain alkyl chain; n = 0, 1, or 2

[0011] In the present application, the use of triphenylmethyl-based carbon radicals as perovskite film layer passivation agents can reduce the surface / bulk defects of perovskite crystals, improve the photoelectric conversion efficiency and service life of perovskite photovoltaic devices.

[0012] Preferably, the R is independently selected from aryl / alkyl amine groups aryl / alkyl phosphine groups alkoxy (-OR1), alkylthiol (-SR1), amido (-NH-CO-R2), carbazolyl wherein R1 is selected from a C1-C6 long chain alkyl chain, substituted or unsubstituted C6-C22 aromatic group, substituted or unsubstituted C5-C20 heteroaryl group, and R2 is selected from a C1-C6 long chain alkyl chain. The selection of these electron-rich N, P, S, O substituents can make the radical more stable while serving as a Lewis base to coordinate with uncoordinated metal cations in perovskite, thereby playing a passivation role.

[0013] Preferably, R1 is selected from methyl, ethyl, and phenyl, and R2 is selected from methyl, to reduce the difficulty of molecular organic synthesis and reduce the cost of materials.

[0014] In the present application, when the R group in the triphenylmethyl-based carbon radical is an aromatic group or a heteroaromatic group, it can be further modified with other R3 groups, and R3 includes aryl / alkyl amine groups aryl / alkyl phosphine groups alkoxy (-OR1), alkylthiol (-SR1), amido (-NH-CO-R2), alkylphosphonic acid group (-R2-PO3H2), alkyl carboxylic acid group (-R2-CO2H), and the like, containing one or more of P, N, S, O substituents, wherein R1 is selected from a C1-C6 long chain alkyl chain, substituted or unsubstituted C6-C22 aromatic group, substituted or unsubstituted C5-C20 heteroaryl group, and R2 is selected from a C1-C6 long chain alkyl chain. These electron-rich substituents enable the radical to coordinate with metal ions (Ni x+ , Sn 4+ , Ti 4+ , etc.) in metal oxide electrodes (ITO, FTO, etc.) or transport layers, as well as organic amine cations (FA +MA + ) and halide anions (I - , Br - ) to play the role of defect passivation and energy level modification.

[0015] In the present application, the number of carbon atoms in the group is limited to a range, which means that the number of carbon atoms in the group can be any integer within the limited range, for example, C6-C20 means that the number of carbon atoms can be 6, 7, 8, 9, 10, 12, 15, 18 or 20, and so on.

[0016] Preferably, the perovskite film layer passivation agent is selected from any one of the following passivation agents:

[0017]

[0018] R3 is H, methyl or methoxy, n = 1, 2 or 3.

[0019] In the present application, the preparation method of the perovskite film layer passivation agent:

[0020] The synthesis of the free radical passivation agent is based on the published tris(2,4,6-trichlorophenyl)methyl radical (TTM) (Angew. Chem., 2015, 127, 7197-7201) and di-perchlorophenyl-(2,3,5,6-tetrachloro-4-bromophenyl)methane (HBrPTM) (The Journal of Organic Chemistry, 1982, 47(2): 259-264) as the initial raw material.

[0021] The synthesis and preparation of the trityl radical passivation agent in the present application include the following methods:

[0022] 1. C-N coupling or C-P coupling between TTM radical and -NHR2 or -PR2- substituent

[0023] 2. Suzuki coupling reaction between TTM or HBrPTM and borate ester of carbazole and its derivatives

[0024] 3. Methoxylation or methylthioethylation of Br on HBrPTM

[0025] 4. Amination and amidation of Br on HBrPTM

[0026] 5. C-N coupling reaction of carbazole and its derivatives with dibromoalkyl or bromoaromatic substituent

[0027] 6. Conversion of bromine on alkyl chain to phosphonate ester by Arbuzov reaction

[0028] 7. Hydrolysis reaction of phosphonate or carbonate

[0029] 8. Benzylization protection and debenzylization of carbazole N-H.

[0030] In another aspect, the present application provides a perovskite precursor solution, which comprises the perovskite film layer passivation agent as described above.

[0031] Preferably, the weight percentage concentration of the perovskite film layer passivation agent in the perovskite precursor solution is 0.1-5%, for example 0.1%, 0.5%, 0.8%, 1%, 1.5%, 1.8%, 2%, 2.5%, 3%, 3.5%, 4%, 4.5% or 5%.

[0032] In another aspect, the present application provides a perovskite passivation film, which comprises the perovskite film layer passivation agent as described above.

[0033] In the present application, the perovskite passivation film is prepared between the perovskite film layer and the hole transport layer film layer by means of solution such as spin coating, slot coating, inkjet printing, screen printing, spray printing, or vacuum thermal evaporation deposition, to play a passivation role.

[0034] In another aspect, the present application provides a perovskite solar cell, which comprises a transparent electrode, a first transport layer, a first interface passivation layer, a perovskite layer, a second interface passivation layer, a second transport layer and a top electrode arranged in sequence; at least one of the first interface passivation layer, the perovskite layer and the second interface passivation layer contains the perovskite film layer passivation agent as described above.

[0035] In the present application, a specially designed triphenylmethyl radical is used as a passivation agent to passivate the perovskite film layer, which has the effect of reducing the surface / bulk defects of perovskite crystals, adjusting the perovskite / transport layer energy level, and improving the photoelectric conversion efficiency and service life of perovskite photovoltaic devices.

[0036] The use of a triphenylmethyl radical to passivate the PVK (perovskite)-HTL (hole transport layer) interface (i.e. containing a triphenylmethyl radical passivation agent in the first interface passivation layer or the second interface passivation layer) has the effects of: ① the electron-donating substituent inside the radical has excellent hole transport capacity, which can assist the hole extraction of perovskite; ② the substituent group modified by the radical substituent can interact with metal oxide-based HTL (NiOx, etc.), reducing the surface defects of HTL, improving the PVK wettability on the surface of HTL, modifying the energy level matching of PVK and HTL, and thus improving the overall device efficiency and service life.

[0037] In the use of the free radical passivation PVK-HTL interface, the PVK-ETL (electron transport layer) interface is passivated by using other commonly used passivation agents, and the effect is to simultaneously modify the two end interfaces of PVK and further improve the performance of the device.

[0038] The perovskite solar cell described in the application can be an n-i-p formal planar structure, that is, the first transport layer is an electron transport layer, and the second transport layer is a hole transport layer; or a p-i-n reverse planar structure, that is, the first transport layer is a hole transport layer, and the second transport layer is an electron transport layer.

[0039] The transparent electrode can be a mixture of one or more of indium tin oxide (ITO), fluorinated tin oxide (FTO), indium zinc oxide (IZO), indium tungsten oxide (IWO), and other transparent oxide electrodes.

[0040] The top electrode can be formed of the same material as the transparent electrode, or can be selected from one or more of silver (Ag), gold (Au), copper (Cu), aluminum (Al), chromium (Cr), and other metals with good conductivity.

[0041] The electron transport layer can be independently selected from one or more of TiO2, SnO2, ZnO, ZnS, Cu(SCN)2, and other n-type inorganic semiconductor materials or C 60 , PC 61 BM, PC 71 BM, and other fullerene derivatives or CDIN, N-PDI, and other organic small molecule materials.

[0042] The hole transport layer can be independently selected from one or more of Spiro-OMeTAD, and other organic small molecule materials, or PTAA, P3HT, PEDOT, and other polymer materials, or 2PACz, and other self-assembled small molecule materials, or NiO x , and other p-type inorganic semiconductor materials.

[0043] The perovskite material is independently selected from MAPb(Br x I 1-x )3, FAPb(Br x I 1-x )3, FA 1-y MA y Pb(Br x I 1-x )3, Cs z FA 1-z Pb(Br x I 1-x )3, Cs z FA 1-y-z MA y Pb(Br x I1-x One of the following 3, wherein 0≤x, y, z≤1, and the solvent is selected from one or more of DMF, DMSO, NMP, 2-ME, and acetonitrile.

[0044] Compared with the prior art, the present invention has the following beneficial effects:

[0045] This invention uses triphenylmethyl carbon radicals as perovskite film passivators, which can reduce surface / bulk defects in perovskite crystals and improve the photoelectric conversion efficiency and lifespan of perovskite photovoltaic devices. Attached Figure Description

[0046] Figure 1 This is a schematic diagram of the structure of the perovskite solar cell of the present invention, wherein 1 is a transparent electrode, 2 is a first transport layer, 3 is a first interface passivation layer, 4 is a perovskite layer, 5 is a second interface passivation layer, 6 is a second transport layer, and 7 is a top electrode.

[0047] Of these, 3 and 5 may be missing, and other auxiliary membrane layers may be located between any two adjacent membrane layers. Detailed Implementation

[0048] The technical solution of the present invention will be further illustrated below through specific embodiments. Those skilled in the art should understand that the embodiments described are merely illustrative of the present invention and should not be construed as limiting the invention in any way.

[0049] Synthesis and characterization of free radical passivator 1:

[0050]

[0051] HBrPTM (1.24 mmol), diethylamine (2.00 mmol), KOH (3.00 mmol), and DMSO (50 mL) solvent were added sequentially to the container. The mixture was refluxed at 120 °C for 48 hours in the dark and under an atmospheric atmosphere. After reflux, the mixture was cooled, and 5% dilute hydrochloric acid solution was added until the pH of the solution was close to 7. After removing the solvent, column chromatography was performed to obtain the intermediate product H1.

[0052] H1 (1.0 equiv) and ultra-dry THF (40 ml) were added sequentially to a container. Then, under a nitrogen atmosphere, potassium tert-butoxide (t-BuOK, 4.0 equiv) was added. The system was then sealed and stirred at room temperature in the dark for 1.5 hours, followed by the addition of tetrachlorobenzoquinone (TCBQ, 2.7 equiv). The mixture was then stirred at room temperature in the dark for another 1.5 hours. After the reaction was complete, the solvent was removed. The crude product was separated by column chromatography to obtain free radical product 1. GC-MS (m / z): theoretical value 796.64; measured value 795.82.

[0053] The embodiment provides a perovskite solar cell, a structural schematic diagram of the perovskite solar cell is as shown in the figure, and the perovskite solar cell comprises, in sequence, a transparent electrode, a first transport layer, a first interface passivation layer, a perovskite layer, a second interface passivation layer, a second transport layer and a top electrode; the perovskite layer contains a perovskite film layer passivation agent 1. Figure 1 The embodiment provides a perovskite solar cell, a structural schematic diagram of the perovskite solar cell is as shown in the figure, and the perovskite solar cell comprises, in sequence, a transparent electrode, a first transport layer, a first interface passivation layer, a perovskite layer, a second interface passivation layer, a second transport layer and a top electrode; the perovskite layer contains a perovskite film layer passivation agent 1.

[0054] Taking a p-i-n transverse plane structure as an example, a preparation method of a small-area (effective area 1mm 2 ) perovskite solar cell is as follows:

[0055] A pre-patterned ITO glass substrate is washed with deionized water, acetone and isopropanol respectively, and then the substrate is dried by using a nitrogen gun, and the substrate is prepared for use after being treated by plasma for 5 minutes. NiO x Nanoparticle aqueous solution (20mg / mL) 100μL is dropped onto the foregoing substrate, spin-coated at 4000 revolutions per minute (rpm) for 30s, and then annealed at 100℃ on a hot plate for 10 minutes to complete the preparation of the hole transport layer NiO x layer. Subsequently, the substrate is transferred to a glove box (nitrogen atmosphere), 65μL of a perovskite solution (DMF:DMSO=4:1) doped with a passivation agent 1 (doping mass fraction 1%) at a concentration of 1.4mol / L is dropped, spin-coated at 2000rpm for 10s, spin-coated at 6000rpm for 30s, 100μL of chlorobenzene antisolvent is dropped at 10s before the spin-coating is completed. After the perovskite spin-coating is completed, the perovskite film layer after passivation is prepared by annealing at 110℃ on a hot plate for 10 minutes. After the annealing is completed, 100μL of a PCBM solution (20mg / mL, chlorobenzene solvent) is dropped, spin-coated at 1000rpm for 30s to complete the preparation of the electron transport layer PCBM layer. Then 20μL of a BCP isopropanol saturated solution is dropped, spin-coated at 6000rpm for 10s to complete the preparation of the auxiliary layer. Finally, 100nm of Ag is vacuum thermal evaporated as a top electrode.

[0056] The preparation method of an n-i-p formal plane structure device is basically the same as that of the transverse device, except that the preparation sequence is changed to: spin-coating SnO2 nanoparticle solution (20mg / mL aqueous solution), spin-coating doped perovskite solution (components are the same as those of the transverse device), spin-coating Spiro-OMeTAD solution (including 72.3mg Spiro-OMeTAD, 29μL 4-tert-butylpyridine, 35μL Li-TFSI acetonitrile solution and 1ml chlorobenzene), and evaporating Ag (100nm).

[0057] Since high efficiency perovskite solar cells usually bind Spiro-OMeTAD as hole transport layer, Spiro-OMeTAD often needs additional doping of hygroscopic Li salt to improve the hole transport capacity, resulting in poor device stability, therefore large area (≥125cm 2 ) perovskite solar cell modules only use inverted planar structure, the preparation method is as follows:

[0058] The FTO substrate is formed with several parallel P1 grooves by P1 laser etching. After cleaning and drying, the substrate is transferred into the RF-PVD chamber, and a 20nm-thick NiO x layer is prepared by RF magnetron sputtering of the NiOx target in an Ar atmosphere, followed by annealing at 300℃ for 10 minutes. Then the substrate is transferred to a slot coater, coated with a layer of perovskite solution doped with 1% of the passivation agent 1, and transferred to a vacuum pre-crystallization device for vacuuming for 40 seconds, followed by annealing at 110℃ for 10 minutes. The above substrate is transferred to a vacuum chamber, and a 20nm-thick C 60 layer and a 5nm-thick BCP layer are evaporated, and then P2 laser etching is performed on the right side of the P1 grooves to form an equal number of parallel P2 grooves, which cut off all the film layers above the FTO. Subsequently, the substrate is again transferred into a vacuum chamber to evaporate 100-200nm of Cu or Ag as a top electrode. Finally, P3 laser etching is performed on the right side of the P2 grooves to form an equal number of parallel P3 grooves, which again cut off all the film layers above the FTO, and P4 laser edge cleaning is performed to remove the ineffective film layers at the edges of the substrate, completing the preparation of the large-area module.

[0059] Example 2

[0060] Synthesis method and characterization of free radical passivation agent 2:

[0061]

[0062] A container is sequentially added with TTM (1.5mmol), diphenylamine derivative (1mmol), Pd(OAc)2 (0.4mmol), P(t-Bu)3 (0.4mmol), Cs2CO3 (4.0mmol) and 20ml of solvent toluene. The mixed solution is refluxed at 100℃ under light shielding and nitrogen atmosphere for 24 hours. After the reflux is completed, the mixed solution is cooled, and 5% dilute hydrochloric acid solution is added until the pH of the solution approaches 7. Then an appropriate amount of water and dichloromethane solution are added for extraction, and the organic phase is dried with anhydrous magnesium sulfate and then rotary evaporated. The crude product is separated by column chromatography to obtain the product 2. GC-MS (m / z): R3=H theoretical value 686.08, actual value 685.62; R3=-CH3 theoretical value 714.13, actual value 713.63; R3=-OCH3 theoretical value 746.13, actual value 745.92.

[0063] The embodiment provides a perovskite solar cell, a structure schematic diagram of the perovskite solar cell is as shown in the figure, and the perovskite solar cell comprises, in sequence, a transparent electrode, a first transport layer, a first interface passivation layer, a perovskite layer, a second interface passivation layer, a second transport layer and a top electrode; the perovskite layer contains a perovskite film layer passivation agent 2. Figure 1 The preparation method of the perovskite solar cell is the same as that in Embodiment 1, and the difference is that the perovskite film layer passivation agent 1 is replaced by the passivation agent 2.

[0064] The preparation method of the perovskite solar cell is the same as that in Embodiment 1, and the difference is that the perovskite film layer passivation agent 1 is replaced by the passivation agent 2.

[0065] Embodiment 3

[0066] The synthesis method and characterization of the radical passivation agent 3 are as follows:

[0067]

[0068] The synthesis of the intermediate product H3 and the synthesis of the passivation agent 2 in Embodiment 2 are basically the same, and the difference is that the diphenylamine in the raw material is replaced by diethyl phosphine. Finally, the intermediate product H3 is obtained.

[0069] The synthesis of the passivation agent 3 from H3 is basically the same as the synthesis of the passivation agent 1 from H1 in Embodiment 1, and the difference is that the H1 in the raw material is replaced by H3, and finally the product passivation agent 3 is obtained. GC-MS (m / z): the theoretical value is 813.61; the measured value is 812.83.

[0070] The embodiment provides a perovskite solar cell, a structure schematic diagram of the perovskite solar cell is as shown in the figure, and the perovskite solar cell comprises, in sequence, a transparent electrode, a first transport layer, a first interface passivation layer, a perovskite layer, a second interface passivation layer, a second transport layer and a top electrode; the perovskite layer contains a perovskite film layer passivation agent 2. Figure 1 The preparation method of the perovskite solar cell is the same as that in Embodiment 1, and the difference is that the perovskite film layer passivation agent 1 is replaced by the passivation agent 2.

[0071] The preparation method of the perovskite solar cell is the same as that in Embodiment 1, and the difference is that the perovskite film layer passivation agent 1 is replaced by the passivation agent 2.

[0072] Embodiment 4

[0073] The synthesis method and characterization of the radical passivation agent 4 are as follows:

[0074]

[0075] In a vessel, TTM (1.0 mmol) was added followed by a solution of (R3Ph)2PNa in THF (0.5 mmol, prepared by reacting R2PH with Na in THF) and the reaction was allowed to proceed for 1 h. Then 2 ml of DMF was added and the reaction was allowed to proceed at 100 °C for 3 h. After removal of the solvent, the target product 4 was obtained by column chromatography. GC-MS (m / z): R = H calcd 703.04, found 702.79; R3= -CH3calcd 731.10, found 730.81; R3= -OCH3calcd 763.09, found 762.85.

[0076] This embodiment provides a perovskite solar cell, a schematic diagram of a structure of the perovskite solar cell is shown in Figure 1 The perovskite solar cell comprises, in sequence, a transparent electrode, a first transport layer, a first interface passivation layer, a perovskite layer, a second interface passivation layer, a second transport layer, and a top electrode; the perovskite layer contains a perovskite film layer passivation agent 4.

[0077] The preparation method of the perovskite solar cell is the same as that in Embodiment 1, except that the perovskite film layer passivation agent 1 is replaced by the passivation agent 4.

[0078] Embodiment 5

[0079] The synthesis method and characterization of the radical passivation agent 5 belong to the published technology, and reference is made to the literature [Tetrahedron Letters 1994, 35, 6529-6532].

[0080] This embodiment provides a perovskite solar cell, a schematic diagram of a structure of the perovskite solar cell is shown in Figure 1 The perovskite solar cell comprises, in sequence, a transparent electrode, a first transport layer, a first interface passivation layer, a perovskite layer, a second interface passivation layer, a second transport layer, and a top electrode; the perovskite layer contains a perovskite film layer passivation agent 5.

[0081] The preparation method of the perovskite solar cell is the same as that in Embodiment 1, except that the perovskite film layer passivation agent 1 is replaced by the passivation agent 5.

[0082] Embodiment 6

[0083] The synthesis method and characterization of the radical passivation agent 6 are as follows:

[0084]

[0085] H6 was prepared by the same method as in Example 1, except that H1 was replaced by H6. GC-MS (m / z): Theoretical value 771.50; found value 770.85.

[0086] H6 was prepared by the same method as in Example 1, except that H1 was replaced by H6. GC-MS (m / z): Theoretical value 771.50; found value 770.85.

[0087] The perovskite solar cell provided in this example has a structure as shown in Figure 1 which comprises a transparent electrode, a first transport layer, a first interface passivation layer, a perovskite layer, a second interface passivation layer, a second transport layer and a top electrode arranged in sequence; the perovskite layer contains the perovskite film layer passivation agent 6.

[0088] The preparation method of the perovskite solar cell is the same as in Example 1, except that the perovskite film layer passivation agent 1 is replaced by the passivation agent 6.

[0089] Example 7

[0090] The synthesis method and characterization of the radical passivation agent 7 belong to the published technology, and reference is made to the literature [J. Org. Chem. 66, 3886-3892 (2001)].

[0091] The perovskite solar cell provided in this example has a structure as shown in Figure 1 which comprises a transparent electrode, a first transport layer, a first interface passivation layer, a perovskite layer, a second interface passivation layer, a second transport layer and a top electrode arranged in sequence; the perovskite layer contains the perovskite film layer passivation agent 7.

[0092] The preparation method of the perovskite solar cell is the same as in Example 1, except that the perovskite film layer passivation agent 1 is replaced by the passivation agent 7.

[0093] Example 8

[0094] The synthesis method and characterization of the radical passivation agent 8 are as follows:

[0095]

[0096] wherein n = 1, 2, 3; R3 = -H, -OMe

[0097] Dissolve 8-1 (12 mmol) in 20 Br(CH2CH2) n Br, then add tetra-t-butyl ammonium bromide (TBABr, 0.25 mmol) and 50% concentration KOH aqueous solution (7.2 ml), and react at 70 °C for 6-20 hours. After the reaction is completed, remove the solvent, and obtain the intermediate product 8-2 by column chromatography.

[0098] In a container, add 8-2 (1.24 mmol), pinacol boronate (1.86 mmol), potassium acetate (5.00 mmol), catalyst Pd(dppf)Cl2(0.062 mmol), and 10 ml of epoxide hexacyclo. Reflux the mixed solution at 80 °C under a nitrogen atmosphere for 48 hours. After the reaction is completed, quench the reaction by adding brine. After the reaction is completed, remove the solvent, and obtain the intermediate product 8-3 by column chromatography.

[0099] In a container, add TTM (1.24 mmol), 7-3 (1.36 mmol), catalyst tetra-(triphenylphosphine) palladium (Pd(Pph3)4) (0.07 mmol), and a mixed solution of toluene (12 ml), K3PO4 (2 mol / L, 8 ml), and ethanol (4 ml). Reflux the mixture at 95 °C under a nitrogen atmosphere and in the dark for 48 hours. After the reaction is completed, adjust the pH of the solution to about 7 and remove the solvent, and obtain the intermediate product 8-4 by column chromatography.

[0100] Dissolve 8-4 (3.02 mmol) in 30 ml of 1,4-dioxane under a nitrogen atmosphere, then dropwise add bromotrimethylsilane, and keep the reaction under a nitrogen atmosphere at 25 °C for 24 hours. After the reaction is completed, remove the solvent, dissolve the remaining solid in 30 ml of methanol, and dropwise add distilled water (150 ml) until the solution becomes transparent. Then continue stirring the reaction for 24 hours. After the reaction is completed, remove the solvent, and obtain the target product 8 by column chromatography. GC-MS (m / z): R3 = -H, n = 1 theoretical value 792.09, actual value 791.58; R3 = -H, n = 2 theoretical value 820.15, actual value 819.70; R3 = -H, n = 3 theoretical value 848.20, actual value 847.62; R3 = -OMe, n = 1 theoretical value 822.12, actual value 821.89; R = -OMe, n = 2 theoretical value 850.17, actual value 849.60; R = -OMe, n = 3 theoretical value 878.23, actual value 877.71;

[0101] This embodiment provides a perovskite solar cell, a schematic structural diagram of which is as shown in Figure 1As shown, including a transparent electrode, a first transport layer, a first interface passivation layer, a perovskite layer, a second interface passivation layer, a second transport layer and a top electrode arranged in sequence; the perovskite layer contains a perovskite film layer passivation agent 8. Among them, the device performance comparison determines that the structure of the passivation agent 8 is optimal for n=1 and R3=-OMe.

[0102] The preparation method of the perovskite solar cell is the same as that of embodiment 1, except that the perovskite film layer passivation agent 1 is replaced by passivation agent 8.

[0103] Embodiment 9

[0104]

[0105] wherein R3=-H, -CH3, -OMe

[0106] A container is added with 9-1 (280 mmol) and an appropriate amount of toluene to dissolve it, then 200 ml of 12 mol / L NaOH aqueous solution is added. The mixed solution is stirred at room temperature for 10 minutes, then tetra-t-butylammonium iodide (Bu4NI, 30 mmol) is added, followed by benzyl bromide (0.57 g, 336 mmol), and stirring at room temperature for three hours. After the reaction is completed, the solvent is removed, and the intermediate product 9-2 is obtained by column chromatography.

[0107] The preparation method of 9-3 from 9-2 is completely consistent with that of 8-3 from 8-2 in terms of material ratio, except that the bromine group is replaced by 9-2 instead of 8-2.

[0108] The preparation method of 9-4 from 9-3 is completely consistent with that of 8-4 from 8-3 in terms of material ratio, except that the boronic ester is replaced by 9-3 instead of 8-3.

[0109] A container is added with 9-4 (2.36 mmol) and 60 ml of solvent DMSO. Under stirring conditions, oxygen is introduced, and 10 ml of potassium tert-butoxide (23.6 mmol) in tetrahydrofuran solution is added, then oxygen is continuously introduced while stirring at room temperature for 45 minutes. After the reaction is completed, the solvent is removed, and the intermediate product 9-5 is obtained by column chromatography.

[0110] A container is added with 9-5 (1 mmol), tris(dibenzyl ketone) palladium (0) (Pd2(dba)3, 0.1 mmol), tri-tert-butyl phosphine tetrafluoroborate (0.2 mmol), sodium tert-butoxide (1, 1 mmol), and 10 ml of toluene, and reacted at 110°C for 24 hours under a nitrogen atmosphere. After the reaction is completed, the solvent is removed, and the intermediate product 9-6 is obtained by column chromatography.

[0111] A mixture of 9-6 (1 mmol), KOH (10 mmol), methanol and tetrahydrofuran (v:v = 1:1) 20 ml was added to a container, and the reaction was carried out at 85°C for 24 hours. After the reaction was completed, the solvent was removed, and the final product 9 was obtained by column chromatography. GC-MS (m / z): R3 = -H theoretical value 804.17, actual value 803.73; R3 = -CH3 theoretical value 818.19, actual value 817.68; R3 = -OMe theoretical value 834.19, actual value 833.82;

[0112] This embodiment provides a perovskite solar cell, a schematic diagram of the structure of the perovskite solar cell is shown in Figure 1 The perovskite solar cell includes a transparent electrode, a first transport layer, a first interface passivation layer, a perovskite layer, a second interface passivation layer, a second transport layer and a top electrode arranged in sequence; the perovskite layer contains a perovskite film layer passivation agent 9. Through device performance comparison, it is confirmed that the optimal structure of the passivation agent 9 is R3 = -OMe.

[0113] The preparation method of the perovskite solar cell is the same as that in Embodiment 1, except that the perovskite film layer passivation agent 1 is replaced by the passivation agent 9.

[0114] Embodiment 10

[0115] The difference between Embodiment 1 and Embodiment 10 is only that the passivation agent 1 is not directly doped into the perovskite film layer, but forms a first interface passivation layer in a transplanar structure (transplanar structure). The preparation method of the interface passivation film layer is to prepare it between the perovskite film layer and the hole transport layer film layer by a solution means (2 mg / L isopropanol solution) of spin coating, which plays a passivation role. The thickness of the film layer is 5 nm.

[0116] Embodiment 11

[0117] The difference between Embodiment 10 and Embodiment 11 is only that the perovskite film layer passivation agent 1 is replaced by 2.

[0118] Embodiment 12

[0119] The difference between Embodiment 10 and Embodiment 12 is only that the perovskite film layer passivation agent 1 is replaced by 3.

[0120] Embodiment 13

[0121] The difference between Embodiment 10 and Embodiment 13 is only that the perovskite film layer passivation agent 1 is replaced by 4.

[0122] Embodiment 14

[0123] The difference between Embodiment 10 and Embodiment 14 is only that the perovskite film layer passivation agent 1 is replaced by 5.

[0124] Embodiment 15

[0125] The only difference between Example 10 and Example 11 is that the perovskite film layer passivation agent 1 is replaced by 6.

[0126] Example 16

[0127] The only difference between Example 10 and Example 11 is that the perovskite film layer passivation agent 1 is replaced by 7.

[0128] Example 17

[0129] The only difference between Example 10 and Example 11 is that the perovskite film layer passivation agent 1 is replaced by 8.

[0130] Example 18

[0131] The only difference between Example 10 and Example 11 is that the perovskite film layer passivation agent 1 is replaced by 9.

[0132] Comparative Example 1

[0133] The only difference between Example 1 and Comparative Example 1 is that the perovskite film layer passivation agent 1 is replaced by OTTM:

[0134]

[0135] Comparative Example 2

[0136] The only difference between Example 10 and Comparative Example 2 is that the perovskite film layer passivation agent 1 is replaced by OTTM.

[0137] Comparative Example 3

[0138] The only difference between Comparative Example 10 and Comparative Example 3 is that no perovskite film layer passivation agent is used.

[0139] The perovskite solar cells of Examples 1-18 and Comparative Examples 1-3 are tested for performance. For uniform conditions, the perovskite solar cell device structure is fixed as a transverse planar structure: FTO (500 nm) / NiO x (~40 nm) / MAPbI3 (~400 nm) / PCBM (~60 nm) / BCP (~10 nm) / Au (120 nm), with reference to the preparation method of Example 1. According to the different examples, 1% of the passivation agent is doped into the MAPbI3 film layer (denoted as @PVK) or is located alone between the MAPbI3 and NiO x film layers (thickness of about 5 nm, denoted as @IL). Except for the transparent electrode FTO and the top electrode Au, the remaining film layers are prepared by solution spin coating, and the effective area of the device is 1 mm 2 .

[0140] The test method refers to the fast measurement method in the group standard T / CPIA 0032-2022 "Current-voltage (I-V) characteristic measurement method of perovskite photovoltaic cells and modules" of China Photovoltaic Industry Association:

[0141] By changing the bias voltage point and simultaneously measuring the current, the I-V characteristics of the measured sample can be obtained.

[0142] a) Place the standard photovoltaic cell on the sample holder so that it is in the measurement plane and ensure that the standard photovoltaic cell is located at the center of the sun simulator exit spot (or the photovoltaic cell normal is parallel to the center line of the sun simulator light source exit beam); according to the calibration value of the standard photovoltaic cell, adjust the solar simulator irradiance on the sample surface (the irradiance non-uniformity of the light source meets the AAA level requirement in IEC 60904-9:2020), and the sample receives an irradiance of 1000 W / m 2 ;

[0143] b) Without changing the settings of the sun simulator, adjust the height and position of the test stand, and install a mask on the measured sample, then replace the standard photovoltaic cell, align the center position, and ensure that the sample surface height is consistent with the standard photovoltaic cell;

[0144] c) Set the scanning direction, voltage range, scanning interval voltage, and scanning interval time, etc. The scanning interval is 0.02 V, and the interval time between adjacent points is 0.3 s. Measure the forward and reverse scanning current-voltage characteristics of the measured photovoltaic cell, and record the open-circuit voltage V oc , short-circuit current I sc , maximum output power P max , fill factor FF, and photoelectric conversion efficiency PCE.

[0145] The test results are shown in Table 1.

[0146] Table 1. Device performance parameters using different passivation agent materials

[0147]

[0148]

[0149]

[0150] As can be seen from Table 1, the radical passivator of the present application can more effectively improve the photoelectric conversion efficiency of the perovskite solar cell than the existing disclosed Comparative Examples 1 and 2 radical OTTM and Comparative Example 3 without adding the passivator. Among them, the promotion effect of passivator 8 (n = 1, R3 = -OMe) and passivator 9 (R3 = -OMe) is the best, and its role as a PVK-HTL interface passivation layer (@IL) is greater than directly doping in the PVK precursor solution (@PVK). The mechanism analysis is as follows: when Comparative Examples 1-2 and Examples 1-9 @PVK, the passivator only contacts with the perovskite crystal, and the defects in the perovskite are passivated by -Cl on the radical and -OMe, -SMe and other groups on the substituent group; and when Examples 8 and 9 @IL, in addition to passivating the perovskite film at the interface through the above-mentioned groups, the -PO3H and -CO2H anchor groups connected by the radical substituent group can effectively anchor the Ni x in the NiO x+ (x≥2) vacancy coordination, play a role in passivating the interface defects of NiO x , the promotion effect on the device performance is greater under the dual action.

[0151] The applicant declares that the perovskite film passivator, its preparation method and application of the present application are illustrated by the above examples, but the present application is not limited to the above examples, that is, it does not mean that the present application must rely on the above examples to be implemented. It should be understood by those skilled in the art that any improvement on the present application, equivalent replacement of the selected materials of the present application, addition of auxiliary ingredients, selection of specific methods, etc. fall within the protection scope and disclosure scope of the present application.

Claims

1. A perovskite film layer passivation agent, characterized in that, The perovskite film layer passivation agent comprises a structure as shown in the following formula: ； R3 is H, methyl or methoxy, n = 1, 2 or 3; Wherein, R3 in compound 2 is not hydrogen.

2. A perovskite precursor solution, characterized in that, The perovskite precursor solution comprises the perovskite film layer passivation agent according to claim 1.

3. The perovskite precursor solution according to claim 2, characterized in that, The perovskite precursor solution comprises the perovskite film layer passivation agent according to claim 1.

4. A perovskite passivation film, characterized by, The perovskite film layer passivation agent comprises a structure as shown in the following formula: ； R3 is H, methyl or methoxy, n = 1, 2 or 3.

5. A perovskite solar cell, characterized by, The perovskite solar cell comprises a transparent electrode, a first transport layer, a first interface passivation layer, a perovskite layer, a second interface passivation layer, a second transport layer and a top electrode arranged in sequence; at least one of the first interface passivation layer, the perovskite layer and the second interface passivation layer comprises a perovskite film layer passivation agent with a structure as shown in the following formula: ； R3 is H, methyl or methoxy, n = 1, 2 or 3.

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