Perovskite absorption layer, finishing solution and removing method for surface defects of perovskite absorption layer, and battery

Abstract

The invention provides a perovskite absorption layer, a finishing solution for surface defects of the perovskite absorption layer, a removing method and a battery. The finishing solution comprises a perovskite dissolving solvent and an anti-solvent, the perovskite dissolving solvent comprises any one or a combination of at least two of DMF, DMSO, NMP, GBL, ACN, 2-ME, DMI, DMAC or DMPU; the anti-solvent comprises any one or a combination of at least two of CB, EA, MB or Et2O. The finishing solution is used for treating a perovskite absorption layer, adjustment can be carried out according to actual conditions, a surface layer with defects and the thickness of 30-60 nm of the perovskite layer is removed, and therefore the defect concentration and strain are greatly reduced on the basis that the light absorption capacity of the perovskite layer is guaranteed; in addition, after the perovskite absorption layer is processed by the finishing solution, the surface appearance and the optical absorption performance of the thin film are kept, the service life of a carrier is prolonged, and a band gap is reduced.

Description

Technical Field

[0001] The invention belongs to the technical field of solar cells, and relates to a finishing solution for removing surface defects of a perovskite absorption layer, in particular to a finishing solution, a removal method and a battery for a perovskite absorption layer and surface defects thereof. Background Art

[0002] In perovskite solar cells, the interface between the perovskite layer and the electron transport layer contains a defect concentration that is approximately 100 times that of the bulk, and the surface of the perovskite layer facing the electron transport layer is usually subject to the greatest strain. The surface of the perovskite layer facing the electron transport layer with such defects acts as a non-radiative recombination center for charge carriers, which can adversely affect the performance of photovoltaic devices. Due to dangling bonds and huge strain, the defect density of the perovskite layer facing the electron transport layer is significantly higher than that in the bulk. This excessive strain leads to a blue shift in the band gap and increased non-radiative recombination, which further adversely affects the performance of photovoltaic devices.

[0003] To remove defective perovskite surfaces, vacuum-assisted solid phase recrystallization, femtosecond laser polishing, and mechanical methods have been demonstrated. However, the thickness of the perovskite layer removed by these strategies is usually limited to less than 20 nm. However, due to the linear growth of strain, the trap density grows logarithmically from the surface to the inside of the perovskite layer, and the region inside the perovskite layer more than 20 nm deep from the surface still has high defects and cannot be removed by these methods in the prior art.

[0004] CN108767117A discloses a perovskite solar cell based on carbon quantum dot doped anti-solvent passivation of grain boundary defects and its preparation method, which belongs to the field of perovskite solar cell technology. It is composed of an ITO conductive glass substrate, a PEDOT:PSS hole transport layer, a carbon quantum dot doped anti-solvent perovskite active layer, a C60 / BCP composite electron transport layer, and an Ag anode, and a toluene anti-solvent doped with carbon quantum dots is added dropwise during the preparation of the perovskite active layer. The document synthesizes an environmentally friendly carbon quantum dot material by a hydrothermal method, dopes the carbon quantum dot material into a toluene anti-solvent, and during the spin coating growth process of the perovskite active layer, a certain amount of carbon quantum dot material is introduced into the perovskite film by using an anti-solvent cleaning, and the carbon quantum dot is used to passivate the grain boundary defects, eliminate the ion transport in the film, and then eliminate the light soaking phenomenon. At the same time, the high conductivity of the carbon quantum dot material is used to improve the conductivity of the perovskite film, improve carrier transport, and then improve device performance. However, the surface of the carbon quantum dot-doped anti-solvent perovskite active layer of the perovskite solar cell facing the C60 / BCP composite electron transport layer still has a high degree of defects, which will adversely affect the performance of the photovoltaic device.

[0005] CN116568055A discloses a method for achieving defect passivation and room temperature encapsulation of a perovskite solar cell by regulating the structure of an organosilicon polymer. First, a telechelic organosilicon polymer is synthesized, and the polymer is introduced into a perovskite light-absorbing layer by an anti-solvent method to achieve defect passivation. In addition, the organosilicon polymer is prepared into a polymer gel by a condensation reaction, and the encapsulation of the perovskite cell is achieved by rapid cross-linking and curing of the polymer gel at room temperature. However, although the perovskite solar cell introduces a telechelic organosilicon polymer into the perovskite light-absorbing layer by an anti-solvent method, which reduces the defects of the perovskite light-absorbing layer to a certain extent, the degree of defect reduction is low and cannot meet the needs in practical applications.

[0006] The methods for reducing defects in the perovskite layer in solar cells disclosed in the prior art all have certain defects, and there is a problem that the defects in the region where the depth of the perovskite layer is more than 20nm from the surface cannot be removed. Therefore, it is very important to develop and design a new type of perovskite absorber layer and its surface defect repair solution, removal method and battery. Summary of the invention

[0007] In view of the deficiencies in the prior art, the present invention aims to provide a repair solution, a removal method and a battery for a perovskite absorption layer and surface defects thereof. The repair solution for removing surface defects of a perovskite absorption layer provided by the present invention comprises a perovskite dissolving solvent and an anti-solvent. The perovskite absorption layer is treated with the repair solution, which can be adjusted according to actual conditions to remove a surface layer of the perovskite layer with a thickness of 30 to 60 nm having defects, thereby greatly reducing the defect concentration and strain on the basis of ensuring the light absorption capacity of the perovskite layer; in addition, after the perovskite absorption layer is treated with the repair solution, not only the surface morphology and optical absorption performance of the film are maintained, but also the carrier lifetime is improved and the band gap is reduced; therefore, after the perovskite absorption layer is treated with the repair solution, the solar cell finally obtained exhibits excellent electrochemical performance.

[0008] To achieve this object, the present invention adopts the following technical solutions:

[0009] In a first aspect, the present invention provides a finishing solution for removing surface defects of a perovskite absorbing layer, the finishing solution comprising a perovskite dissolving solvent and an anti-solvent;

[0010] The perovskite dissolving solvent includes any one or a combination of at least two of DMF, DMSO, NMP, GBL, ACN, 2-ME, DMI, DMAC or DMPU;

[0011] The anti-solvent comprises any one or a combination of at least two of CB, EA, MB or Et2O;

[0012] The volume ratio of the perovskite dissolving solvent to the anti-solvent in the trimming solution is (5-20):(80-95).

[0013] The perovskite dissolving solvent in the present invention includes any one of DMF (N, N dimethylformamide), DMSO (dimethyl sulfoxide), NMP (N methylpyrrolidone), GBL (γ butyrolactone), ACN (acetonitrile), 2-ME (2-methoxyethanol), DMI (1,3-dimethyl-2-imidazolidinone), DMAC (dimethylacetamide) or DMPU (1,3-dimethyl-3,4,5,6-tetrahydro-2 (1H) -pyrimidinone) or a combination of at least two thereof, and typical but non-limiting combinations include a combination of DMF and DMSO, a combination of NMP and GBL, a combination of ACN and 2-ME, a combination of DMI and DMAC, a combination of DMAC and DMPU, or a combination of DMF, DMSO and NMP.

[0014] The anti-solvent in the present invention includes any one of CB (chlorobenzene), EA (ethyl acetate), MB (methyl benzoate) or Et2O (diethyl ether) or a combination of at least two of them. Typical but non-limiting combinations include a combination of CB and EA, a combination of EA and MB, a combination of MB and Et2O, or a combination of CB, EA and MB.

[0015] The volume ratio of the perovskite dissolving solvent to the anti-solvent in the trimming solution of the present invention is (5-20):(80-95), for example, it can be 5:80, 5:83, 5:87, 5:89, 5:91, 5:93, 5:95, 7:80, 7:83, 7:87, 7:89, 7:91, 7:93, 7:95, 13:80, 13:83, 13:87, 13: 89, 13:91, 13:93, 13:95, 17:80, 17:83, 17:87, 17:89, 17:91, 17:93, 17:95, 20:80, 20:83, 20:87, 20:89, 20:91, 20:93 or 20:95, but are not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0016] The trimming solution for removing surface defects of a perovskite absorption layer provided by the present invention comprises a perovskite dissolving solvent and an anti-solvent. The perovskite absorption layer is treated with the trimming solution, and can be adjusted according to actual conditions to remove a surface layer of the perovskite layer with a thickness of 30 to 60 nm having defects, thereby greatly reducing the defect concentration and strain on the basis of ensuring the light absorption capacity of the perovskite layer; in addition, after the perovskite absorption layer is treated with the trimming solution, not only the surface morphology and optical absorption performance of the film are maintained, but also the carrier lifetime is improved and the band gap is reduced; therefore, after the perovskite absorption layer is treated with the trimming solution, the solar cell finally obtained exhibits excellent electrochemical performance.

[0017] Preferably, the perovskite dissolving solvent includes any one of ACN, 2-ME or NMP or a combination of at least two thereof, and typical but non-limiting combinations include a combination of ACN and 2-ME, a combination of 2-ME and NMP, or a combination of ACN, 2-ME and NMP.

[0018] In the present invention, when any one of ACN, 2-ME or NMP or a combination of at least two thereof is used as the perovskite dissolving solvent, since ACN, 2-ME or NMP has a relatively low boiling point, the risk of residual solvent penetrating the perovskite grain boundary and thus destroying the perovskite layer can be minimized.

[0019] In a second aspect, the present invention provides a method for removing surface defects of a perovskite absorption layer, the removal method comprising:

[0020] The surface of the perovskite absorption layer is treated with the trimming solution described in the first aspect to obtain the perovskite absorption layer after surface defects are removed.

[0021] Preferably, the treatment comprises a pre-treatment and a heat treatment performed sequentially, and the pre-treatment comprises spin coating and / or screen printing.

[0022] Preferably, the spin coating comprises spin coating the trimming solution on the surface of the perovskite absorption layer, the spin coating has a rotation speed of 200 to 600 rpm and a time of 20 to 40 s.

[0023] The spin coating rotation speed in the present invention is 200-600 rpm, for example, it can be 200 rpm, 250 rpm, 300 rpm, 350 rpm, 400 rpm, 450 rpm, 500 rpm, 550 rpm or 600 rpm, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0024] The spin coating time in the present invention is 20 to 40 seconds, for example, 20 seconds, 22 seconds, 24 seconds, 26 seconds, 28 seconds, 30 seconds, 32 seconds, 34 seconds, 36 seconds, 38 seconds or 40 seconds, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0025] Preferably, the screen printing includes dripping a trimming solution onto the surface of the perovskite absorption layer, and the screen printing time is 10 to 20 seconds, for example, 10 seconds, 12 seconds, 14 seconds, 16 seconds, 18 seconds or 20 seconds, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0026] Preferably, the heat treatment is carried out at a temperature of 90 to 120° C. and for a time of 3 to 7 minutes.

[0027] The temperature of the heat treatment in the present invention is 90-120°C, for example, it can be 90°C, 95°C, 100°C, 105°C, 110°C, 115°C or 120°C, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0028] The heat treatment time in the present invention is 3 to 7 minutes, for example, it can be 3 minutes, 3.5 minutes, 4 minutes, 4.5 minutes, 5 minutes, 5.5 minutes, 6 minutes, 6.5 minutes or 7 minutes, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0029] In a third aspect, the present invention provides a perovskite absorption layer after surface defects are removed, and the perovskite absorption layer after surface defects are removed is obtained by the removal method described in the second aspect.

[0030] In a fourth aspect, the present invention provides a solar cell, comprising the perovskite absorption layer after surface defects are removed as described in the third aspect.

[0031] Preferably, the solar cell comprises a perovskite solar cell, a perovskite crystalline silicon stacked cell or a flexible perovskite cell.

[0032] The numerical range described in the present invention not only includes the point values ​​listed above, but also includes any point values ​​between the above numerical ranges that are not listed. Due to space limitations and for the sake of simplicity, the present invention no longer exhaustively lists the specific point values ​​included in the range.

[0033] Compared with the prior art, the present invention has the following beneficial effects:

[0034] (1) The trimming solution for removing surface defects of the perovskite absorber layer provided by the present invention comprises a perovskite dissolving solvent and an anti-solvent. The perovskite absorber layer is treated with the trimming solution, and the trimming solution can be adjusted according to actual conditions to remove the surface layer of the perovskite layer with defects of 30 to 60 nm in thickness, thereby greatly reducing the defect concentration and strain on the basis of ensuring the light absorption capacity of the perovskite layer; in addition, after the perovskite absorber layer is treated with the trimming solution, not only the surface morphology and optical absorption performance of the film are maintained, but also the carrier lifetime is improved and the band gap is reduced; therefore, after the perovskite absorber layer is treated with the trimming solution, the solar cell finally obtained exhibits excellent electrochemical performance;

[0035] (2) In the present invention, when any one of ACN, 2-ME or NMP or a combination of at least two thereof is used as the perovskite dissolving solvent, since ACN, 2-ME or NMP has a relatively low boiling point, the risk of residual solvent penetrating the perovskite grain boundary and thus destroying the perovskite layer can be minimized. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 It is a schematic diagram of processing the surface defects of the perovskite absorption layer in the preparation method of the perovskite solar cell provided in Application Examples 1 and 4 to 24.

[0037] Figure 2 This is a surface morphology image of the perovskite absorption layer before removing surface defects in Application Example 8.

[0038] Figure 3 This is the surface morphology of the perovskite absorption layer after removing surface defects in Application Example 8.

[0039] Among them, 1-ITO glass substrate; 2-SAM hole transport layer; 3-perovskite absorption layer; 4-perovskite absorption layer after removing surface defects. DETAILED DESCRIPTION

[0040] The technical solution of the present invention is further described below by specific implementation methods. It should be understood by those skilled in the art that the embodiments are only to help understand the present invention and should not be regarded as specific limitations of the present invention.

[0041] Example 1

[0042] This embodiment provides a finishing solution for removing surface defects of a perovskite absorption layer, wherein the finishing solution comprises a perovskite dissolving solvent ACN and an anti-solvent CB in a volume ratio of 5:95;

[0043] This embodiment also provides a method for removing surface defects of a perovskite absorption layer, the removal method comprising:

[0044] The trimming solution described in this embodiment is spin-coated on the surface of the perovskite absorption layer at a rotation speed of 200 rpm for 30 seconds, and then heat-treated at 100° C. for 5 minutes to obtain the perovskite absorption layer 4 after removing surface defects.

[0045] Example 2

[0046] This embodiment provides a finishing solution for removing surface defects of a perovskite absorption layer, which is the same as that of Embodiment 1 except that the volume ratio of the perovskite dissolving solvent ACN to the anti-solvent CB is 10:90.

[0047] This embodiment also provides a method for removing surface defects of a perovskite absorption layer, which is the same as that of Embodiment 1 except that the trimming solution is replaced with the trimming solution in this embodiment.

[0048] Example 3

[0049] This embodiment provides a finishing solution for removing surface defects of a perovskite absorption layer, which is the same as that of Embodiment 1 except that the volume ratio of the perovskite dissolving solvent ACN to the anti-solvent CB is 15:85.

[0050] This embodiment also provides a method for removing surface defects of a perovskite absorption layer, which is the same as that of Embodiment 1 except that the trimming solution is replaced with the trimming solution in this embodiment.

[0051] Example 4

[0052] This embodiment provides a finishing solution for removing surface defects of a perovskite absorption layer, which is the same as that of Embodiment 1 except that the volume ratio of the perovskite dissolving solvent ACN to the anti-solvent CB is 20:80.

[0053] This embodiment also provides a method for removing surface defects of a perovskite absorption layer, which is the same as that of Embodiment 1 except that the trimming solution is replaced with the trimming solution in this embodiment.

[0054] Example 5

[0055] This embodiment provides a finishing solution for removing surface defects of a perovskite absorption layer. The finishing solution is the same as that in Embodiment 1.

[0056] This embodiment also provides a method for removing surface defects of a perovskite absorption layer, which is the same as that of Embodiment 1 except that the rotation speed of the spin coating is 300 rpm.

[0057] Example 6

[0058] This embodiment provides a finishing solution for removing surface defects of a perovskite absorption layer. The finishing solution is the same as that in Embodiment 1.

[0059] This embodiment also provides a method for removing surface defects of a perovskite absorption layer, which is the same as that of Embodiment 1 except that the rotation speed of the spin coating is 400 rpm.

[0060] Example 7

[0061] This embodiment provides a finishing solution for removing surface defects of a perovskite absorption layer. The finishing solution is the same as that in Embodiment 1.

[0062] This embodiment also provides a method for removing surface defects of a perovskite absorption layer, which is the same as that of Embodiment 1 except that the rotation speed of the spin coating is 500 rpm.

[0063] Example 8

[0064] This embodiment provides a finishing solution for removing surface defects of a perovskite absorption layer. The finishing solution is the same as that in Embodiment 1.

[0065] This embodiment also provides a method for removing surface defects of a perovskite absorption layer, which is the same as that of Embodiment 1 except that the rotation speed of the spin coating is 600 rpm.

[0066] Example 9

[0067] This embodiment provides a finishing solution for removing surface defects of a perovskite absorption layer, which is the same as that of Embodiment 1 except that the perovskite dissolving solvent ACN is replaced by 2-ME.

[0068] This embodiment also provides a method for removing surface defects of a perovskite absorption layer, which is the same as that of Embodiment 1 except that the trimming solution is replaced with the trimming solution in this embodiment and the spin coating speed is 400 rpm.

[0069] Example 10

[0070] This embodiment provides a finishing solution for removing surface defects of a perovskite absorption layer, which is the same as that of Embodiment 1 except that the perovskite dissolving solvent ACN is replaced by NMP.

[0071] This embodiment also provides a method for removing surface defects of a perovskite absorption layer, which is the same as that of Embodiment 1 except that the trimming solution is replaced with the trimming solution in this embodiment and the spin coating speed is 400 rpm.

[0072] Embodiment 11

[0073] This embodiment provides a finishing solution for removing surface defects of a perovskite absorber layer, which is the same as that of Embodiment 1 except that the anti-solvent CB is replaced by EA.

[0074] This embodiment also provides a method for removing surface defects of a perovskite absorption layer, which is the same as that of Embodiment 1 except that the trimming solution is replaced with the trimming solution in this embodiment and the spin coating speed is 400 rpm.

[0075] Example 12

[0076] This embodiment provides a finishing solution for removing surface defects of a perovskite absorber layer, which is the same as that of Embodiment 1 except that the anti-solvent CB is replaced by MB.

[0077] This embodiment also provides a method for removing surface defects of a perovskite absorption layer, which is the same as that of Embodiment 1 except that the trimming solution is replaced with the trimming solution in this embodiment and the spin coating speed is 400 rpm.

[0078] Embodiment 13

[0079] This embodiment provides a finishing solution for removing surface defects of a perovskite absorber layer, which is the same as that of Embodiment 1 except that the anti-solvent CB is replaced by Et2O.

[0080] This embodiment also provides a method for removing surface defects of a perovskite absorption layer, which is the same as that of Embodiment 1 except that the trimming solution is replaced with the trimming solution in this embodiment and the spin coating speed is 400 rpm.

[0081] Embodiment 14

[0082] This embodiment provides a finishing solution for removing surface defects of a perovskite absorption layer. The finishing solution is the same as that in Embodiment 1.

[0083] This embodiment also provides a method for removing surface defects of a perovskite absorption layer, the removal method comprising:

[0084] The trimming solution described in this embodiment is dripped onto the surface of the perovskite absorption layer, screen printing is performed for 10 seconds, and then heat treatment is performed at 100° C. for 5 minutes to obtain the perovskite absorption layer 4 after removing surface defects.

[0085] Embodiment 15

[0086] This embodiment provides a finishing solution for removing surface defects of a perovskite absorption layer. The finishing solution is the same as that in Embodiment 1.

[0087] This embodiment also provides a method for removing surface defects of a perovskite absorption layer, the removal method comprising:

[0088] The trimming solution described in this embodiment is dripped onto the surface of the perovskite absorption layer, screen printing is performed for 15 seconds, and then heat treatment is performed at 100° C. for 5 minutes to obtain the perovskite absorption layer 4 after removing surface defects.

[0089] Example 16

[0090] This embodiment provides a finishing solution for removing surface defects of a perovskite absorption layer. The finishing solution is the same as that in Embodiment 1.

[0091] This embodiment also provides a method for removing surface defects of a perovskite absorption layer, the removal method comprising:

[0092] The trimming solution described in this embodiment is dripped onto the surface of the perovskite absorption layer, screen printing is performed for 20 seconds, and then heat treatment is performed at 100° C. for 5 minutes to obtain the perovskite absorption layer 4 after removing surface defects.

[0093] Embodiment 17

[0094] This embodiment provides a finishing solution for removing surface defects of a perovskite absorption layer, which is the same as that of Embodiment 1 except that the volume ratio of the perovskite dissolving solvent ACN to the anti-solvent CB is 2:98.

[0095] This embodiment also provides a method for removing surface defects of a perovskite absorption layer, which is the same as that of Embodiment 1 except that the trimming solution is replaced with the trimming solution in this embodiment.

[0096] Embodiment 18

[0097] This embodiment provides a finishing solution for removing surface defects of a perovskite absorption layer, which is the same as that of Embodiment 1 except that the volume ratio of the perovskite dissolving solvent ACN to the anti-solvent CB is 25:75.

[0098] This embodiment also provides a method for removing surface defects of a perovskite absorption layer, which is the same as that of Embodiment 1 except that the trimming solution is replaced with the trimming solution in this embodiment.

[0099] Embodiment 19

[0100] This embodiment provides a finishing solution for removing surface defects of a perovskite absorption layer. The finishing solution is the same as that in Embodiment 1.

[0101] This embodiment also provides a method for removing surface defects of a perovskite absorption layer, which is the same as that of Embodiment 1 except that the rotation speed of the spin coating is 100 rpm.

[0102] Embodiment 20

[0103] This embodiment provides a finishing solution for removing surface defects of a perovskite absorption layer. The finishing solution is the same as that in Embodiment 1.

[0104] This embodiment also provides a method for removing surface defects of a perovskite absorption layer, which is the same as that of Embodiment 1 except that the rotation speed of the spin coating is 800 rpm.

[0105] Embodiment 21

[0106] This embodiment provides a finishing solution for removing surface defects of a perovskite absorption layer, which is the same as that of Embodiment 1 except that the perovskite dissolving solvent ACN is replaced by DMF.

[0107] This embodiment also provides a method for removing surface defects of a perovskite absorption layer, which is the same as that of Embodiment 1 except that the trimming solution is replaced with the trimming solution in this embodiment and the spin coating speed is 400 rpm.

[0108] Embodiment 22

[0109] This embodiment provides a finishing solution for removing surface defects of a perovskite absorption layer, which is the same as that of Embodiment 1 except that the perovskite dissolving solvent ACN is replaced by DMSO.

[0110] This embodiment also provides a method for removing surface defects of a perovskite absorption layer, which is the same as that of Embodiment 1 except that the trimming solution is replaced with the trimming solution in this embodiment and the spin coating speed is 400 rpm.

[0111] Comparative Example 1

[0112] This comparative example provides a finishing solution for removing surface defects of a perovskite absorption layer, which is the same as Example 1 except that the perovskite dissolving solvent ACN is omitted from the finishing solution.

[0113] This comparative example also provides a method for removing surface defects of a perovskite absorption layer, which is the same as Example 1 except that the trimming solution is replaced with the trimming solution in this comparative example.

[0114] Comparative Example 2

[0115] This comparative example provides a finishing solution for removing surface defects of a perovskite absorber layer, which is the same as Example 1 except that the anti-solvent CB in the finishing solution is omitted.

[0116] This comparative example also provides a method for removing surface defects of a perovskite absorption layer, which is the same as Example 1 except that the trimming solution is replaced with the trimming solution in this comparative example.

[0117] Application Example 1

[0118] This application example provides a perovskite solar cell, which comprises an ITO glass substrate 1, a SAM hole transport layer 2 with a thickness of 10 nm, a perovskite absorption layer 4 with a thickness of 500 nm after surface defects are removed by the removal method provided in Example 1, a C60 electron transport layer with a thickness of 15 nm, a SnO2 electron transport layer with a thickness of 15 nm, and an Ag electrode with a thickness of 120 nm, which are stacked in sequence;

[0119] The preparation method of the perovskite solar cell is as follows:

[0120] The ITO glass is ultrasonically cleaned with detergent, deionized water, acetone and anhydrous ethanol respectively, and the ultrasonic cleaning time is 15 minutes respectively. After the cleaning, the ITO glass is dried to obtain an ITO glass substrate 1;

[0121] A 1 mg / ml MeO-4PACz ethanol solution was spin-coated on the surface of the ITO glass substrate 1 at a speed of 3000 rpm for 30 seconds, and then heated at 100° C. for 10 minutes to form a self-assembled monolayer (SAM) as the SAM hole transport layer 2;

[0122] 1.5mmolPbI2, 1.4mmolFAI and 0.7mmolMACl were dissolved in 0.8mL of DMF and 0.2mL of DMSO to obtain a first solution, 1mmolMABr and 1mmolPbBr2 were dissolved in 0.8mL of DMF and 0.2mL of DMSO to obtain a second solution, and 1.5mmolCsI was dissolved in 1mL of DMSO to obtain a third solution. The three solutions were mixed in a volume ratio of 72:28:5. Then, tetrakis-(4-aminophenyl)ethylene iodide at a concentration of 3 mg / mL was added to obtain a perovskite precursor solution; 200 μL of the perovskite precursor solution was then dripped onto the surface of the SAM hole transport, and the solution was spin-coated at a speed of 3500 rpm for 30 seconds. During the spin-coating period of 20 seconds, 300 μL of chlorobenzene was quickly dripped as an anti-solvent; the spin-coated substrate was then placed on a heating table for annealing at a temperature of 80° C. for 10 minutes to obtain a perovskite absorption layer 3;

[0123] like Figure 1 As shown, the surface defects of the perovskite absorption layer 3 are treated by the removal method provided in Example 1 to obtain the perovskite absorption layer 4 after the surface defects are removed;

[0124] After removing the surface defects of the perovskite absorption layer 4, a C60 electron transport layer is deposited by evaporation, a SnO2 electron transport layer is prepared on the surface of the C60 electron transport layer by atomic layer deposition, and then an Ag electrode is deposited on the surface of the SnO2 electron transport layer by evaporation to obtain a perovskite solar cell.

[0125] Application Example 2

[0126] The present application example provides a perovskite crystalline silicon stacked cell, the perovskite crystalline silicon stacked cell comprises an Ag gate electrode, a first ITO transparent conductive layer, a P-type hydrogenated amorphous silicon doped layer, a first intrinsic hydrogenated amorphous silicon passivation layer, an N-type single crystal silicon layer, a second intrinsic hydrogenated amorphous silicon passivation layer, an N-type hydrogenated amorphous silicon doped layer, a second ITO transparent conductive layer, and a NiO x Hole transport layer, perovskite absorption layer 4 after removing surface defects by the removal method provided in Example 6, LiF passivation layer, C60 electron transport layer, SnO2 electron transport layer, third ITO transparent conductive layer, the surface of the third ITO transparent conductive layer is also provided with MgF2 anti-reflection layer and Ag electrode

[0127] The thickness of the N-type single crystal silicon layer is 150 μm; the thickness of the first intrinsic hydrogenated amorphous silicon passivation layer is 2 nm; the thickness of the second intrinsic hydrogenated amorphous silicon passivation layer is 2 nm; the thickness of the P-type hydrogenated amorphous silicon doping layer is 9 nm; the thickness of the N-type hydrogenated amorphous silicon doping layer is 6 nm; the thickness of the second ITO transparent conductive layer is 30 nm; the NiO x The thickness of the hole transport layer is 20nm, the thickness of the perovskite layer is 500nm; the thickness of the LiF passivation layer is 1nm; the thickness of the C60 electron transport layer is 15nm; the thickness of the SnO2 electron transport layer is 15nm; the thickness of the first ITO transparent conductive layer is 110nm; the thickness of the third ITO transparent conductive layer is 110nm; the thickness of the Ag gate line electrode is 180nm; the thickness of the Ag electrode is 1μm; the thickness of the MgF2 anti-reflection layer is 90nm.

[0128] The preparation method of the perovskite crystalline silicon stacked cell comprises:

[0129] (1) The N-type single crystal silicon layer is sequentially pre-cleaned with ozone deionized water, post-cleaned with an ozone hydrofluoric acid mixed solution, and cleaned and etched with a hydrofluoric acid and nitric acid mixed solution to form an N-type single crystal silicon layer with a double-sided velvet surface;

[0130] (2) on both sides of the N-type single crystal silicon layer with double-sided velvet obtained in step (1), a first intrinsic hydrogenated amorphous silicon passivation layer and a second intrinsic hydrogenated amorphous silicon passivation layer are respectively deposited by PECVD, and then a P-type hydrogenated amorphous silicon doping layer is deposited on the surface of the first intrinsic hydrogenated amorphous silicon passivation layer, and an N-type hydrogenated amorphous silicon doping layer is deposited on the surface of the second intrinsic hydrogenated amorphous silicon passivation layer;

[0131] (3) preparing a second transparent conductive layer on the surface of the N-type hydrogenated amorphous silicon doped layer obtained in step (2) by magnetron sputtering, and then preparing NiO on the surface of the obtained second transparent conductive layer by magnetron sputtering x The hole transport layer is then formed on the obtained NiO x A perovskite layer is prepared on the hole transport layer, and the surface defects of the perovskite absorption layer are treated by the removal method provided in Example 1 to obtain a perovskite absorption layer 4 after the surface defects are removed;

[0132] Then, a LiF passivation layer is prepared on the surface of the perovskite absorption layer 4 after removing the surface defects by evaporation, a C60 electron transport layer is prepared by evaporation, and a SnO2 electron transport layer is prepared by atomic layer deposition;

[0133] The method for preparing the perovskite layer is as follows: 1.5mmolPbI2, 1.4mmolFAI and 0.7mmolMACl are dissolved in 0.8mL of DMF and 0.2mL of DMSO to obtain a first solution, 1mmolMABr and 1mmolPbBr2 are dissolved in 0.8mL of DMF and 0.2mL of DMSO to obtain a second solution, and 1.5mmolCsI is dissolved in 1mL of DMSO to obtain a third solution. The three solutions are mixed according to 72: 28:5 volume ratio, and then add tetrakis-(4-aminophenyl)ethylene iodide with a concentration of 3 mg / mL to obtain a perovskite precursor solution; then drop 200 μL of the perovskite precursor solution on the substrate coated with the hole transport layer 2, spin coat at a speed of 3500 rpm for 30 seconds, and quickly drop 300 μL of chlorobenzene as an anti-solvent when spin coating for 20 seconds; then place the spin-coated substrate on a heating table for annealing, the annealing temperature is 80° C., and the annealing time is 10 min;

[0134] (4) A first transparent conductive layer is prepared on the surface of the P-type hydrogenated amorphous silicon doped layer obtained in step (2), and a third transparent conductive layer is prepared on the surface of the SnO2 electron transport layer obtained in step (3); Ag gate lines are screen-printed on the surface of the first transparent conductive layer and then sintered and solidified to obtain Ag gate line electrodes, and Ag electrodes and MgF2 anti-reflection layers are evaporated on the surface of the third transparent conductive layer using a mask to obtain a perovskite crystalline silicon stacked cell.

[0135] Application Example 3

[0136] This application example provides a flexible perovskite battery, which includes a PEN (ITO) substrate stacked in sequence, a SAM hole transport layer with a thickness of 10 nm, a perovskite absorption layer 4 with a thickness of 500 nm after surface defects are removed by the removal method provided in Example 6, a C60 electron transport layer with a thickness of 25 nm, a BCP buffer layer with a thickness of 6 nm, and an Ag electrode with a thickness of 100 nm;

[0137] The preparation method of the flexible perovskite battery is:

[0138] The PEN(ITO) substrate was treated with UV-ozone for 15 min to obtain a PEN(ITO) substrate;

[0139] A 0.3 mg / ml MeO-2PACz ethanol solution was spin-coated on the surface of the ITO glass substrate 1 at a speed of 4000 rpm for 30 seconds, and then heated at 100° C. for 10 minutes to form a self-assembled monolayer (SAM) as a SAM hole transport layer;

[0140] 1.5mmolPbI2, 1.4mmolFAI and 0.7mmolMACl were dissolved in 0.8mL of DMF and 0.2mL of DMSO to obtain a first solution, 1mmolMABr and 1mmolPbBr2 were dissolved in 0.8mL of DMF and 0.2mL of DMSO to obtain a second solution, and 1.5mmolCsI was dissolved in 1mL of DMSO to obtain a third solution. The three solutions were mixed in a volume ratio of 72:28:5. Then, tetrakis-(4-aminophenyl)ethylene iodide with a concentration of 3 mg / mL was added to obtain a perovskite precursor solution; 200 μL of the perovskite precursor solution was then dropped onto the surface of the SAM hole transport layer, and the solution was spin-coated at a speed of 3500 rpm for 30 seconds, and 300 μL of chlorobenzene was quickly dropped as an anti-solvent during the spin coating for 20 seconds; the spin-coated substrate was then placed on a heating table for annealing at a temperature of 80° C. for 10 minutes to obtain a perovskite absorption layer;

[0141] The surface defects of the perovskite absorption layer are treated by the removal method provided in Example 6 to obtain the perovskite absorption layer 4 after the surface defects are removed;

[0142] Then, a C60 electron transport layer, a BCP buffer layer and an Ag electrode are sequentially deposited on the surface of the perovskite absorption layer 4 after surface defects are removed by thermal evaporation to obtain a flexible perovskite battery.

[0143] Application Example 4

[0144] This application example provides a perovskite solar cell, which is the same as Application Example 1 except that the perovskite absorption layer 4 after surface defects are removed by the removal method provided in Example 1 is replaced by the perovskite absorption layer 4 after surface defects are removed by the removal method provided in Example 2.

[0145] Application Example 5

[0146] This application example provides a perovskite solar cell, which is the same as application example 1 except that the perovskite absorption layer 4 after surface defects are removed by the removal method provided in embodiment 1 is replaced by the perovskite absorption layer 4 after surface defects are removed by the removal method provided in embodiment 3.

[0147] Application Example 6

[0148] This application example provides a perovskite solar cell, which is the same as Application Example 1 except that the perovskite absorption layer 4 after surface defects are removed by the removal method provided in Example 1 is replaced by the perovskite absorption layer 4 after surface defects are removed by the removal method provided in Example 4.

[0149] Application Example 7

[0150] This application example provides a perovskite solar cell, which is the same as Application Example 1 except that the perovskite absorption layer 4 after surface defects are removed by the removal method provided in Example 1 is replaced by the perovskite absorption layer 4 after surface defects are removed by the removal method provided in Example 5.

[0151] Application Example 8

[0152] This application example provides a perovskite solar cell, which is the same as application example 1 except that the perovskite absorption layer 4 after the surface defects are removed by the removal method provided in embodiment 1 is replaced by the perovskite absorption layer 4 after the surface defects are removed by the removal method provided in embodiment 6;

[0153] Among them, the surface morphology of the perovskite absorption layer before removing the surface defects in this application example is as follows Figure 2 As shown; the surface morphology of the perovskite absorption layer after removing the surface defects in this application example is shown Figure 3 shown.

[0154] Application Example 9

[0155] This application example provides a perovskite solar cell, which is the same as Application Example 1 except that the perovskite absorption layer 4 after surface defects are removed by the removal method provided in Example 1 is replaced by the perovskite absorption layer 4 after surface defects are removed by the removal method provided in Example 7.

[0156] Application Example 10

[0157] This application example provides a perovskite solar cell, which is the same as Application Example 1 except that the perovskite absorption layer 4 after surface defects are removed by the removal method provided in Example 1 is replaced by the perovskite absorption layer 4 after surface defects are removed by the removal method provided in Example 8.

[0158] Application Example 11

[0159] This application example provides a perovskite solar cell, which is the same as Application Example 1 except that the perovskite absorption layer 4 after surface defects are removed by the removal method provided in Example 1 is replaced by the perovskite absorption layer 4 after surface defects are removed by the removal method provided in Example 9.

[0160] Application Example 12

[0161] This application example provides a perovskite solar cell, which is the same as Application Example 1 except that the perovskite absorption layer 4 after surface defects are removed by the removal method provided in Example 1 is replaced by the perovskite absorption layer 4 after surface defects are removed by the removal method provided in Example 10.

[0162] Application Example 13

[0163] This application example provides a perovskite solar cell, which is the same as Application Example 1 except that the perovskite absorption layer 4 after surface defects are removed by the removal method provided in Example 1 is replaced by the perovskite absorption layer 4 after surface defects are removed by the removal method provided in Example 11.

[0164] Application Example 14

[0165] This application example provides a perovskite solar cell, which is the same as Application Example 1 except that the perovskite absorption layer 4 after surface defects are removed by the removal method provided in Example 1 is replaced by the perovskite absorption layer 4 after surface defects are removed by the removal method provided in Example 12.

[0166] Application Example 15

[0167] This application example provides a perovskite solar cell, which is the same as Application Example 1 except that the perovskite absorption layer 4 after surface defects are removed by the removal method provided in Example 1 is replaced by the perovskite absorption layer 4 after surface defects are removed by the removal method provided in Example 13.

[0168] Application Example 16

[0169] This application example provides a perovskite solar cell, which is the same as Application Example 1 except that the perovskite absorption layer 4 after surface defects are removed by the removal method provided in Example 1 is replaced by the perovskite absorption layer 4 after surface defects are removed by the removal method provided in Example 14.

[0170] Application Example 17

[0171] This application example provides a perovskite solar cell, which is the same as Application Example 1 except that the perovskite absorption layer 4 after surface defects are removed by the removal method provided in Example 1 is replaced by the perovskite absorption layer 4 after surface defects are removed by the removal method provided in Example 15.

[0172] Application Example 18

[0173] This application example provides a perovskite solar cell, which is the same as Application Example 1 except that the perovskite absorption layer 4 after surface defects are removed by the removal method provided in Example 1 is replaced by the perovskite absorption layer 4 after surface defects are removed by the removal method provided in Example 16.

[0174] Application Example 19

[0175] This application example provides a perovskite solar cell, which is the same as Application Example 1 except that the perovskite absorption layer 4 after surface defects are removed by the removal method provided in Example 1 is replaced by the perovskite absorption layer 4 after surface defects are removed by the removal method provided in Example 17.

[0176] Application Example 20

[0177] This application example provides a perovskite solar cell, which is the same as Application Example 1 except that the perovskite absorption layer 4 after surface defects are removed by the removal method provided in Example 1 is replaced by the perovskite absorption layer 4 after surface defects are removed by the removal method provided in Example 17.

[0178] Application Example 21

[0179] This application example provides a perovskite solar cell, which is the same as Application Example 1 except that the perovskite absorption layer 4 after surface defects are removed by the removal method provided in Example 1 is replaced by the perovskite absorption layer 4 after surface defects are removed by the removal method provided in Example 19.

[0180] Application Example 22

[0181] This application example provides a perovskite solar cell, which is the same as Application Example 1 except that the perovskite absorption layer 4 after surface defects are removed by the removal method provided in Example 1 is replaced by the perovskite absorption layer 4 after surface defects are removed by the removal method provided in Example 20.

[0182] Application Example 23

[0183] This application example provides a perovskite solar cell, which is the same as Application Example 1 except that the perovskite absorption layer 4 after surface defects are removed by the removal method provided in Example 1 is replaced by the perovskite absorption layer 4 after surface defects are removed by the removal method provided in Example 21.

[0184] Application Example 24

[0185] This application example provides a perovskite solar cell, which is the same as Application Example 1 except that the perovskite absorption layer 4 after surface defects are removed by the removal method provided in Example 1 is replaced by the perovskite absorption layer 4 after surface defects are removed by the removal method provided in Example 22.

[0186] Comparative application example 1

[0187] This comparative application example provides a perovskite solar cell, which is the same as Application Example 1 except that the perovskite absorption layer 4 after surface defects are removed by the removal method provided in Example 1 is replaced by the perovskite absorption layer 4 after surface defects are removed by the removal method provided in Comparative Example 1.

[0188] Comparative Application Example 2

[0189] This comparative application example provides a perovskite solar cell, which is the same as Application Example 1 except that the perovskite absorption layer 4 after surface defects are removed by the removal method provided in Example 1 is replaced by the perovskite absorption layer 4 after surface defects are removed by the removal method provided in Comparative Example 2.

[0190] Comparative Application Example 3

[0191] This comparative application example provides a perovskite solar cell, which is the same as Example 1 except that the perovskite absorption layer 4 after the surface defects are removed by the removal method provided in Example 1 is replaced by the perovskite absorption layer 3 without defect removal (that is, the surface defects of the perovskite absorption layer 3 are processed by the removal method provided in Example 1 in the preparation method of the perovskite crystalline silicon stacked cell to obtain the perovskite absorption layer 4 after the surface defects are removed).

[0192] The test environment is controlled at 25°C by a cooling controller, and the perovskite cells, perovskite crystalline silicon stacked cells and flexible perovskite cells provided in the above application examples and application comparison examples are tested for photoelectric conversion efficiency (PCE), short-circuit current (Jsc), open-circuit voltage (Voc), and fill factor (FF) by a solar simulator and an IV tester, wherein the current and voltage are collected by a source meter, and the light intensity of the solar simulator needs to be calibrated by a "standard wafer" (standard performance cell wafer). Finally, the test results of the perovskite solar cells provided in application examples 1, 4 to 22 and application comparison examples 1 to 3 are shown in Table 1; the test results of the perovskite crystalline silicon stacked cells provided in application example 2 and the flexible perovskite cells provided in application example 3 are shown in Table 2.

[0193] Table 1

[0194]

[0195]

[0196] Table 2

[0197]

[0198] From Tables 1 and 2, we can get:

[0199] (1) It can be seen from Application Examples 1 to 18 that when the perovskite absorption layer 3 is treated with the trimming solution and removal method provided in Examples 1 to 16, the surface layer of the perovskite layer with a thickness of 30 to 60 nm having defects can be removed; in addition, after the perovskite absorption layer 3 is treated with the trimming solution, the perovskite absorption layer 4 after the surface defects are removed has better light absorption performance, higher carrier lifetime and smaller band gap;

[0200] (2) By comparing Application Examples 1, 4 to 6 with Application Examples 19 and 20, it can be seen that the volume ratio of the perovskite dissolving solvent to the anti-solvent in the trimming solution provided by the present invention will affect the performance of the perovskite absorption layer 4 and the solar cell after the surface defects are removed; when the volume ratio of the perovskite dissolving solvent to the anti-solvent is (5 to 20): (80 to 95), it is beneficial to obtain a perovskite absorption layer 4 and a solar cell with better performance after the surface defects are removed. This is because when the volume ratio of the perovskite dissolving solvent to the anti-solvent is (5 to 20): (80 to 95), the surface layer of the perovskite layer with a thickness of 30 to 60 nm having defects can be removed, thereby greatly reducing the defect concentration and strain on the basis of ensuring the light absorption capacity of the perovskite layer;

[0201] (3) By comparing Application Examples 1, 7 to 10 with Application Examples 21 and 22, it can be seen that in the method for removing surface defects of the perovskite absorption layer provided by the present invention, the rotation speed of spin coating will affect the performance of the perovskite absorption layer 4 and the solar cell after the surface defects are removed; when the rotation speed of spin coating is 200 to 600 rpm, it is beneficial to obtain a perovskite absorption layer 4 and a solar cell with better performance after the surface defects are removed. This is because when the rotation speed of spin coating is 200 to 600 rpm, the thickness of the surface layer with defects of the perovskite layer removed is 30 to 60 nm, thereby greatly reducing the defect concentration and strain on the basis of ensuring the light absorption capacity of the perovskite layer;

[0202] (4) By comparing Application Examples 8, 11-12 with Application Examples 23 and 24, it can be seen that when the perovskite dissolving solvent in the trimming solution provided by the present invention is ACN, 2-ME or NMP, it is beneficial to obtain a perovskite absorption layer 4 and a solar cell with better performance after removing surface defects. This is because ACN, 2-ME or NMP has a relatively low boiling point, which can minimize the risk of residual solvent penetrating the perovskite grain boundary and thus destroying the perovskite layer;

[0203] (4) By comparing Application Example 1 with Comparative Application Examples 1 to 3, it can be seen that the trimming solution for removing surface defects of the perovskite absorption layer provided by the present invention contains a perovskite dissolving solvent and an anti-solvent. The perovskite absorption layer 3 is treated with the trimming solution, which can be adjusted according to actual conditions to remove the surface layer of the perovskite absorption layer 3 with a thickness of 30 to 60 nm, thereby greatly reducing the defect concentration and strain on the basis of ensuring the light absorption capacity of the perovskite absorption layer 3; in addition, after the perovskite absorption layer 3 is treated with the trimming solution, not only the surface morphology and optical absorption performance of the film are maintained, but also the carrier lifetime is improved and the band gap is reduced; therefore, after the perovskite absorption layer 3 is treated with the trimming solution, the solar cell finally obtained exhibits excellent electrochemical performance.

[0204] The above description is only a specific implementation mode of the present invention, but the protection scope of the present invention is not limited thereto. Those skilled in the art should understand that any changes or substitutions that can be easily thought of by those skilled in the art within the technical scope disclosed by the present invention are within the protection scope and disclosure scope of the present invention.

Claims

1. A finishing solution for removing surface defects of a perovskite absorber layer, characterized in that: The trimming solution includes a perovskite dissolving solvent and an anti-solvent; The perovskite dissolving solvent includes any one or a combination of at least two of DMF, DMSO, NMP, GBL, ACN, 2-ME, DMI, DMAC or DMPU; The anti-solvent comprises any one or a combination of at least two of CB, EA, MB or Et2O; The volume ratio of the perovskite dissolving solvent to the anti-solvent in the trimming solution is (5-20):(80-95).

2. The trimming solution according to claim 1, characterized in that The perovskite dissolving solvent includes any one of ACN, 2-ME or NMP, or a combination of at least two of them.

3. A method for removing surface defects of a perovskite absorption layer, characterized in that: The removal method comprises: The surface of the perovskite absorption layer is treated with the trimming solution according to claim 1 or 2 to obtain the perovskite absorption layer after removing surface defects.

4. The removal method according to claim 3, characterized in that: The treatment includes a pre-treatment and a heat treatment performed sequentially, wherein the pre-treatment includes spin coating and / or screen printing.

5. The removal method according to claim 4, characterized in that: The spin coating includes spin coating the trimming solution on the surface of the perovskite absorption layer, the spin coating has a rotation speed of 200 to 600 rpm and a time of 20 to 40 seconds.

6. The removal method according to claim 4 or 5, characterized in that: The screen printing comprises dripping a trimming solution onto the surface of the perovskite absorption layer, and the screen printing time is 10 to 20 seconds.

7. The removal method according to any one of claims 4 to 6, characterized in that: The heat treatment temperature is 90-120° C. and the time is 3-7 minutes.

8. A perovskite absorption layer after removing surface defects, characterized in that: The perovskite absorption layer after removing surface defects is obtained by the removal method according to any one of claims 3 to 7.

9. A solar cell, characterized in that: The solar cell comprises the perovskite absorption layer after surface defects are removed as claimed in claim 8.

10. The solar cell according to claim 9, characterized in that: The solar cell includes a perovskite solar cell, a perovskite crystalline silicon stacked cell or a flexible perovskite cell.

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