Perovskite solar cell and surface passivator, passivation method and preparation method thereof

Abstract

The invention belongs to the technical field of solar cells, and provides a perovskite solar cell and a surface passivator, a passivation method and a preparation method thereof. The surface passivator is a decamethylene diamine hydrochloride solution containing 1, 10-decamethylene diamine hydrochloride (the concentration of the 1, 10-decamethylene diamine hydrochloride in the decamethylene diamine hydrochloride solution is 1-3 mg / mL) and isopropanol. According to the invention, the decamethylene diamine hydrochloride solution is used as a surface passivating agent, so that surface defects of the tin dioxide electron transport layer can be effectively passivated; amino groups at the two ends of 1, 10-decamethylene diamine hydrochloride can be anchored on the surface or the grain boundary of the perovskite layer, non-radiative recombination at the interface can be effectively inhibited, and surface defects of the perovskite layer are passivated; a hydrophobic long chain in the middle of the 1, 10-decamethylene diamine hydrochloride can improve the moisture resistance of the surface of the perovskite layer; 1, 10-decamethylene diamine hydrochloride is larger in ion size, and does not enter perovskite crystal lattices to damage the perovskite structure; therefore, the performance and the long-term stability of the perovskite solar cell can be effectively improved.

Description

Technical Field

[0001] The present invention relates to the technical field of solar cells, and in particular to a perovskite solar cell and a surface passivator, a passivation method and a preparation method thereof. Background Art

[0002] In traditional perovskite solar cells, the perovskite film undergoes rapid nucleation and crystallization during the annealing process due to the high annealing temperature, which may result in a smaller perovskite grain size and too many grain boundary defects in the perovskite film, which is not conducive to the transport of carriers. At the same time, there are inevitably a large number of defects in the perovskite film, which are mainly concentrated on the surface of the perovskite film, which will lead to a large number of non-radiative recombination at the interface adjacent to the perovskite film. In addition, there will also be a large number of oxygen vacancy defects in the tin oxide electron transport layer of the perovskite solar cell, which will affect the stability at the interface between it and the perovskite layer and increase charge recombination.

[0003] Based on this, the prior art uses Good's buffer containing aminosulfonic acid (or Good's buffer containing aminocarboxylic acid) as an additive to the perovskite precursor solution to passivate the defects of the perovskite; or uses biguanide hydrochloride or thiourea and urea as an additive to the perovskite precursor solution to passivate its defects through the amine group of the additive and the halide ion vacancies in the perovskite layer; or uses trifluoro-anilinium salt as an additive to the perovskite precursor solution to passivate the defects through the amine group and improve the hydrophobicity of the perovskite film. However, the additives introduced in the above prior art do not contain hydrophobic functional groups, so the effect of improving the moisture resistance of the perovskite film is poor, and the passivation effect is poor.

[0004] Therefore, Publication No. CN116056533A also provides a perovskite precursor solution, which passivates the defects of the perovskite film by adding an additive octyl ammonium chloride (OACl) during the preparation of the perovskite precursor solution, and OACl has a long alkyl chain, which can enhance the hydrophobicity of the perovskite and increase the perovskite grain size, improve the moisture resistance of the perovskite film, and improve the stability and performance of the perovskite solar cell. However, this perovskite precursor solution still focuses on the bulk passivation of the perovskite film, but cannot effectively passivate the surface of the perovskite film, and most of the defects are formed on the surface of the perovskite film, so its improvement on the passivation effect is relatively limited; moreover, the octyl ammonium chloride in the perovskite precursor solution has a poor effect on improving the moisture resistance of the surface of the perovskite layer. Therefore, this perovskite precursor solution is difficult to achieve further improvement in the performance (such as open circuit voltage, short circuit current density, fill factor and energy conversion efficiency) and long-term stability of perovskite solar cells. Summary of the invention

[0005] The purpose of the present invention is to provide a perovskite solar cell and a surface passivator, a passivation method and a preparation method thereof in view of the deficiencies in the prior art.

[0006] Based on this, the present invention discloses a surface passivator for a perovskite solar cell, which is a decanediamine hydrochloride solution, wherein the decanediamine hydrochloride solution comprises 1,10-decanediamine hydrochloride and isopropanol;

[0007] Wherein, the concentration of 1,10-decanediamine hydrochloride in the decanediamine hydrochloride solution is 1-3 mg / mL.

[0008] The present invention also discloses a passivation method for a perovskite solar cell, comprising the following steps:

[0009] S1, preparing a substrate having a tin dioxide electron transport layer on the surface;

[0010] S2, coating the perovskite precursor solution on the surface of the tin dioxide electron transport layer, and preparing a perovskite layer on the surface of the tin dioxide electron transport layer after low temperature assisted slow annealing;

[0011] S3, applying a decanediamine hydrochloride solution on the surface of the perovskite layer, and annealing to passivate the surface of the perovskite layer;

[0012] In step S3, the decanediamine hydrochloride solution is the surface passivator for perovskite solar cells described above in the present invention.

[0013] Preferably, after step S1, the following step is also included: applying a decanediamine hydrochloride solution on the surface of the tin dioxide electron transport layer, and annealing to passivate the surface of the tin dioxide electron transport layer; wherein the decanediamine hydrochloride solution is a surface passivator for perovskite solar cells described above in the present invention.

[0014] Further preferably, the surface passivation uses 80-100 μL of decanediamine hydrochloride solution; after the surface is coated with the decanediamine hydrochloride solution, annealing is performed at 100-120° C. for 5-10 min to complete the surface passivation.

[0015] Further preferably, before the surface passivation of the tin dioxide electron transport layer is performed, the method further comprises the following step: performing ultraviolet ozone treatment on the substrate having the tin dioxide electron transport layer on the surface for 15-20 minutes.

[0016] Preferably, in step S2, the low temperature assisted slow annealing comprises: annealing the perovskite layer coated with a decanediamine hydrochloride solution at 70-80°C for 8-10 min, and then annealing at 100-110°C for 8-10 min.

[0017] Further preferably, step S2 specifically includes: coating 40-50 μL of the perovskite precursor solution on the surface of the tin dioxide electron transport layer, and adding 200-220 μL of chlorobenzene anti-solvent 5-7 seconds after the start of coating, and then performing low-temperature assisted slow annealing to obtain the perovskite layer with a thickness of 450-550 nm on the surface of the tin dioxide electron transport layer.

[0018] Preferably, before step S2, a perovskite precursor solution preparation step is also included: lead iodide with a concentration of 1 to 1.6 mol / L and methyl ammonium iodide with a concentration of 1 to 1.6 mol / L are dissolved in a mixed solvent of dimethyl sulfoxide and dimethylformamide with a volume ratio of 5:1 to 9:1, and stirred for 2-3 hours to obtain the perovskite precursor solution.

[0019] The passivation method for perovskite solar cells of the present invention optimizes the quality of the perovskite layer through a low-temperature assisted slow annealing process in the process of preparing the perovskite layer, slows down the nucleation and crystallization rate of the perovskite, makes the perovskite grains grow further, reduces the perovskite grain boundary defects, and thus improves the carrier transmission characteristics; and further, uses a decanediamine hydrochloride solution as a surface passivator, and deposits 1,10-decanediamine hydrochloride (DDADCL) on the surface of the perovskite layer to achieve upper interface passivation (that is, surface passivation of the perovskite layer, so that the 1,10-decanediamine hydrochloride can be deposited between the perovskite layer and the carbon electrode). ), or further preferably: 1,10-decanediamine hydrochloride is deposited on the surface of the electron transport layer and the surface of the perovskite layer to achieve double interface passivation (that is, the surface passivation of the perovskite layer and the surface passivation of the electron transport layer, so that 1,10-decanediamine hydrochloride can be deposited at the interface between the perovskite layer and the electron transport layer, and at the interface between the perovskite layer and the carbon electrode), which can more effectively inhibit non-radiative recombination at the interface and more effectively passivate surface defects, and because the 1,10-decanediamine hydrochloride ions are large in size, they will not enter the perovskite lattice and destroy the perovskite structure.

[0020] Therefore, using decanediamine hydrochloride solution as a surface passivator and adopting the passivation method for perovskite solar cells of the present invention can more effectively passivate the defects on the surface of the perovskite layer and the surface of the tin dioxide electron transport layer, and further improve the efficiency and stability of perovskite devices without hole transport layers (such as perovskite solar cells).

[0021] The present invention also discloses a method for preparing a perovskite solar cell, comprising the following preparation steps:

[0022] Step 1: Cleaning, drying and UV-ozone treating the substrate in sequence;

[0023] Step 2: using the passivation method for a perovskite solar cell described above in the present invention to prepare a perovskite layer and perform surface passivation;

[0024] Step 3: Prepare a carbon electrode on the surface of the passivated perovskite layer.

[0025] The present invention also discloses a perovskite solar cell, which is prepared by the preparation method of the perovskite solar cell described above in the present invention.

[0026] The present invention also discloses a photovoltaic module, which comprises the perovskite solar cell described above in the present invention.

[0027] Compared with the prior art, the present invention has at least the following beneficial effects:

[0028] The present invention uses a decanediamine hydrochloride solution as a surface passivator for a perovskite device (such as a perovskite solar cell). 1,10-decanediamine hydrochloride can effectively passivate oxygen vacancy defects in an electron transport layer (such as a tin dioxide electron transport layer) through its chloride ions; at the same time, 1,10-decanediamine hydrochloride can also effectively passivate uncoordinated lead ion defects in the perovskite layer through its amine functional groups, and form hydrogen bonds with the perovskite, thereby enhancing interface stability and stabilizing the structure; and the hydrophobic alkyl chain of 1,10-decanediamine hydrochloride can also increase the moisture resistance of the surface of the perovskite layer, inhibit water decomposition, and reduce water damage to the perovskite layer, which is beneficial to improving the stability of devices such as perovskite solar cells.

[0029] Moreover, unlike substances with a single amine functional group (such as octylamine chloride (OACl)), the chemical structure of 1,10-decanediamine hydrochloride has an amine functional group at each end. The amine groups at both ends of 1,10-decanediamine hydrochloride can interact well with the perovskite layer and anchor on the surface or grain boundary of the perovskite layer. The combination with the perovskite layer is stronger, further enhancing the interface stability, more effectively inhibiting the non-radiative recombination at the interface, and more effectively passivating the surface defects of the perovskite layer, achieving a better passivation effect; and the anchoring of the amine groups at both ends of 1,10-decanediamine hydrochloride allows the hydrophobic long chain in the middle of 1,10-decanediamine hydrochloride to be more fully exposed to the outside, which can more effectively protect the perovskite layer from being decomposed by water, and further improve the moisture resistance of the surface of the perovskite layer; due to the larger size of the 1,10-decanediamine hydrochloride ion, it will not enter the perovskite lattice to destroy the perovskite structure.

[0030] Therefore, the present invention uses decanediamine hydrochloride solution as a surface passivating agent, which can more effectively improve the performance (such as open circuit voltage, short circuit current density, fill factor and energy conversion efficiency) and long-term stability of perovskite solar cells. DETAILED DESCRIPTION

[0031] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below in conjunction with specific implementation methods.

[0032] A method for preparing a perovskite solar cell of the present invention comprises the following preparation steps:

[0033] Step 1: Cut 1×1cm 2 The indium tin oxide (ITO) glass substrate is placed in a cleaning rack and ultrasonically cleaned in 300-400 mL (preferably 400 mL) of ethanol, detergent, ultrapure water and ethanol for 15-20 min (preferably 20 min); then the cleaned ITO glass substrate is placed in an oven and dried at 50-70° C. (preferably 60° C.) for 15-20 min (preferably 20 min).

[0034] Step 2: Treat the dried ITO glass substrate with UV ozone for 15-20 minutes (preferably 15 minutes). Mix 200 μL of 15wt% tin dioxide (SnO) aqueous dispersion with 800 μL of ultrapure water, and stir thoroughly to obtain a tin oxide solution with a volume ratio of 1:4 between the tin dioxide aqueous dispersion and ultrapure water; then take 40-50 μL (preferably 45 μL) of the tin oxide solution, and apply the tin oxide solution to the 1×1 cm2 glass substrate treated with UV ozone at a spin coating speed of 4000 r / min and a spin coating time of 30 seconds. 2 The tin dioxide electron transport layer is prepared on the surface of the ITO glass substrate, and then placed on a heating platform at 150-180° C. (preferably 180° C.) for annealing for 30-40 min (preferably 30 min) to obtain a tin dioxide electron transport layer on the surface of the ITO glass substrate.

[0035] Step 3: Treat the ITO glass substrate with the tin dioxide electron transport layer deposited in step 2 with ultraviolet ozone for 15-20 minutes (preferably 15 minutes). Take 80-100 μL (preferably 90 μL) of 1-3 mg / mL (preferably 2 mg / mL) decanediamine hydrochloride solution as a surface passivator, and apply the decanediamine hydrochloride solution on the surface of the tin dioxide electron transport layer at a spin coating speed of 5000 r / min and a spin coating time of 20 seconds, and then place it on a heating table at 100-120°C (preferably 110°C) for annealing for 5-10 minutes (preferably 8 minutes) to complete the surface passivation of the tin dioxide electron transport layer.

[0036] In step 3, a decanediamine hydrochloride solution is used as a surface passivating agent, and the decanediamine hydrochloride solution includes 1,10-decanediamine hydrochloride (DDADCL) and isopropyl alcohol (IPA). Specifically, in the decanediamine hydrochloride solution, the content of 1,10-decanediamine hydrochloride is 1 to 3 mg (preferably 2 mg), and the amount of isopropyl alcohol is 1 mL.

[0037] Step 4: Preparation of perovskite precursor solution: Weigh lead iodide (PbI2) and methyl ammonium iodide (MAI) of the same concentration, dissolve in a mixed solvent of dimethyl sulfoxide (DMSO) and dimethylformamide (DMF) with a volume ratio of 5:1 to 9:1 (preferably 9:1) (the total amount of the mixed solvent is 1 mL), stir well for 2-3 hours (preferably 3 hours) to obtain a perovskite precursor solution. 40-50 μL (preferably 45 μL) of the perovskite precursor solution is coated on the surface of the passivated tin dioxide electron transport layer at a spin coating speed of 4000 r / min and a spin coating time of 30 s, and 200-220 μL (preferably 220 μL) of chlorobenzene (CB) anti-solvent is added dropwise 5-7 seconds (preferably 6 seconds) after the start of spin coating, and the solution is first annealed on a heating table at 70-80°C (preferably 75°C) for 8-10 min (preferably 8 min), and then annealed on a heating table at 100-110°C (preferably 110°C) for 8-10 min (preferably 10 min) to obtain a perovskite layer on the surface of the passivated tin dioxide electron transport layer.

[0038] In step 4, the perovskite precursor solution includes lead iodide (PbI2), methyl ammonium iodide (MAI) and an organic solvent. Specifically, in the perovskite precursor solution, the concentration of lead iodide is 1 to 1.6 mol / L (preferably 1.3 mol / L), the concentration of methyl ammonium iodide is 1 to 1.6 mol / L (preferably 1.3 mol / L), the organic solvent is a mixed solution of dimethylformamide (DMF) and dimethyl sulfoxide (DMSO), and the volume ratio of dimethylformamide to dimethyl sulfoxide is 5:1 to 9:1 (preferably 9:1). In step 4, the thickness of the perovskite layer is 450-550 nm (preferably 500 nm).

[0039] Step 5: Take 80-100 μL (preferably 90 μL) of 1-3 mg / mL (preferably 2 mg / mL) 1,10-decanediamine hydrochloride (DDADCL) solution as a surface passivator, and apply the decanediamine hydrochloride solution on the surface of the perovskite layer at a spin coating speed of 5000 r / min and a spin coating time of 20 s, and then place it on a heating table at 100-120°C (preferably 110°C) for annealing for 5-10 min (preferably 8 min) to complete the surface passivation of the perovskite layer.

[0040] The above steps 3-5 are a passivation method for a perovskite solar cell of the present invention; alternatively, the above step 3 is omitted, and the above steps 4-5 are used as another passivation method for a perovskite solar cell of the present invention.

[0041] Step 6: Take 20-30 mg (preferably 25 mg) of carbon slurry, use a glass slide to scrape the carbon slurry on the surface of the passivated perovskite layer, and then place it on a heating table at 100-120°C (preferably 110°C) for annealing for 20-30 min (preferably 25 min) to prepare a carbon electrode on the surface of the perovskite layer, thereby obtaining a double-interface passivated perovskite solar cell of the present invention.

[0042] Example 1

[0043] A method for preparing a perovskite solar cell in this embodiment includes the following preparation steps:

[0044] Step 1: Cut 1×1cm 2 The indium tin oxide (ITO) glass substrate was placed in a cleaning rack and ultrasonically cleaned in 400 mL of ethanol, detergent, ultrapure water and ethanol for 20 minutes in sequence; then the cleaned ITO glass substrate was placed in an oven and dried at 60° C. for 20 minutes.

[0045] Step 2: Treat the dried ITO glass substrate with UV ozone for 15 minutes. Mix 200 μL of 15wt% tin dioxide aqueous dispersion with 800 μL of ultrapure water, stir thoroughly to obtain a tin oxide solution with a volume ratio of 1:4 between the tin dioxide aqueous dispersion and ultrapure water; then take 45 μL of the tin oxide solution, and apply the tin oxide solution on the surface of the ITO glass substrate treated with UV ozone at a spin coating speed of 4000 r / min and a spin coating time of 30 seconds, and then anneal on a heating table at 180°C for 30 minutes to obtain a tin oxide electron transport layer on the surface of the ITO glass substrate.

[0046] Step 3: The ITO glass substrate with the tin dioxide electron transport layer deposited in step 2 was subjected to UV ozone treatment for 15 minutes. 90 μL of 2 mg / mL decanediamine hydrochloride solution was taken as a surface passivator, and the decanediamine hydrochloride solution was coated on the surface of the tin dioxide electron transport layer at a spin coating speed of 5000 r / min and a spin coating time of 20 seconds, and then placed on a heating table at 110°C for annealing for 8 minutes to complete the surface passivation of the tin dioxide electron transport layer.

[0047] In step 3, a decanediamine hydrochloride solution is used as a surface passivating agent, and the decanediamine hydrochloride solution includes 2 mg of 1,10-decanediamine hydrochloride and 1 mL of isopropanol.

[0048] Step 4: Preparation of perovskite precursor solution: Weigh lead iodide and methyl ammonium iodide of the same concentration, dissolve in a mixed solvent of dimethyl sulfoxide and dimethylformamide with a volume ratio of 9:1 (the total amount of the mixed solvent is 1 mL), and stir thoroughly for 3 hours to obtain a perovskite precursor solution. 45 μL of the perovskite precursor solution is applied on the surface of the passivated tin dioxide electron transport layer at a spin coating speed of 4000 r / min and a spin coating time of 30 seconds, and 220 μL of chlorobenzene antisolvent is added dropwise 6 seconds after the start of spin coating, and then placed on a heating table at 75°C for annealing for 8 minutes, and then placed on a heating table at 110°C for annealing for 10 minutes to obtain a perovskite layer on the surface of the passivated tin dioxide electron transport layer.

[0049] In step 4, the perovskite precursor solution includes lead iodide with a concentration of 1.3 mol / L, methyl ammonium iodide (MAI) with a concentration of 1.3 mol / L, and an organic solvent (a mixed solution of dimethylformamide and dimethyl sulfoxide in a volume ratio of 9:1). In step 4, the thickness of the perovskite layer is 500 nm.

[0050] Step 5: Take 90 μL of 2 mg / mL decanediamine hydrochloride solution as a surface passivator, and apply the decanediamine hydrochloride solution on the surface of the perovskite layer at a spin coating speed of 5000 r / min and a spin coating time of 20 s, and then anneal on a heating table at 110°C for 8 minutes to complete the surface passivation of the perovskite layer.

[0051] The above steps 3-5 are a passivation method for a perovskite solar cell of this embodiment.

[0052] Step 6: Take 25 mg of carbon slurry, use a glass slide to scrape the carbon slurry on the surface of the passivated perovskite layer, and then place it on a heating table at 110°C for annealing for 25 minutes to prepare a carbon electrode on the surface of the perovskite layer, thereby obtaining a double-interface passivated perovskite solar cell (DDADCL double-interface passivated perovskite solar cell) of this embodiment.

[0053] Example 2

[0054] The method for preparing a perovskite solar cell of this embodiment refers to Example 1, and the difference between the method and Example 1 is that:

[0055] In this embodiment, step 3 of embodiment 1 (the step of passivating the surface of the tin dioxide electron transport layer) is omitted, so this embodiment produces a perovskite solar cell with interface passivation on DDADCL (that is, surface passivation of the perovskite layer, which occurs at the interface between the perovskite layer and the carbon electrode).

[0056] Comparative Example 1

[0057] The method for preparing a perovskite solar cell in this comparative example refers to Example 1, and the difference between the method and Example 1 is that:

[0058] This comparative example omits step 3 (the step of passivating the surface of the tin dioxide electron transport layer) and step 5 (the step of passivating the surface of the perovskite layer) of Example 1, so this comparative example produces a perovskite solar cell without interface passivation.

[0059] Comparative Example 2

[0060] The method for preparing a perovskite solar cell in this comparative example refers to Example 1, and the difference between the method and Example 1 is that:

[0061] In this comparative example, step 5 (the step of passivating the surface of the perovskite layer) of Example 1 was omitted, so that a perovskite solar cell with interface passivation under DDADCL (i.e., surface passivation of the tin dioxide electron transport layer, which passivation occurred at the interface between the perovskite layer and the tin dioxide electron transport layer) was prepared in this comparative example.

[0062] Perovskite solar cells

[0063] Comparative Example 3

[0064] The method for preparing a perovskite solar cell in this comparative example refers to Example 1, and the difference between the method and Example 1 is that:

[0065] In this comparative example, step 3 of Example 1 (the step of passivating the surface of the tin dioxide electron transport layer) is omitted, and the active ingredient 1,10-decanediamine hydrochloride (DDADCL) of the surface passivator in step 5 of Example 1 is replaced by octylamine chloride (OACl) in this comparative example, so that a perovskite solar cell with interface passivation on OACl is prepared in this comparative example.

[0066] Comparative Example 4

[0067] The method for preparing a perovskite solar cell in this comparative example refers to Example 1, and the difference between the method and Example 1 is that:

[0068] The effective ingredient DDADCL of the surface passivator in step 3 and step 5 of Example 1 is replaced by OACl in this comparative example, so an OACl double-interface passivated perovskite solar cell is prepared in this comparative example.

[0069] Comparative Example 5

[0070] The method for preparing a perovskite solar cell in this comparative example refers to Example 1, and the difference between the method and Example 1 is that:

[0071] In this comparative example, step 3 and step 5 of Example 1 are omitted, and 2 mg of 1,10-decanediamine hydrochloride is further added to the tin oxide solution in step 2 of this comparative example, and 2 mg of decanediamine hydrochloride solution is further added to the perovskite precursor solution in step 4 of this comparative example, that is, in this comparative example, DDADCL is added to both the prepared tin dioxide electron transport layer and the perovskite layer to achieve passivation, so this comparative example prepares a double DDADCL-added passivated perovskite solar cell.

[0072] Performance Testing

[0073] The performance of the perovskite solar cells prepared in Examples 1-2 and Comparative Examples 1-5 was tested respectively, and the test results are shown in Tables 1-3 below:

[0074] Table 1

[0075]

[0076]

[0077] Single-layer interface passivation (such as DDADCL lower interface passivation in Comparative Example 2, or DDADCL upper interface passivation in Example 2) can only passivate one interface defect between the perovskite layer and the tin dioxide electron transport layer or the perovskite layer and the carbon electrode. Double-layer interface passivation (such as DDADCL double interface passivation in Example 1) can passivate interface defects more comprehensively, and the passivation effect is better. Therefore, referring to Table 1, compared with Comparative Examples 1-2 and Example 2, the performance of the perovskite solar cell of Example 1 (such as open circuit voltage, short circuit current density, fill factor and energy conversion efficiency) has been further improved.

[0078] Table 2

[0079]

[0080] The chemical structure of 1,10-decanediamine hydrochloride (DDADCL) has an amine functional group at each end, which can achieve a better passivation effect than a single amine functional group substance (such as octyl ammonium chloride (OACl) etc.) as a surface passivator. Therefore, referring to Table 2, compared with Comparative Example 3, the performance of the perovskite solar cell of Example 2 (such as open circuit voltage, short circuit current density, fill factor and energy conversion efficiency) has been further improved; compared with Comparative Example 4, the performance of the perovskite solar cell of Example 1 (such as open circuit voltage, short circuit current density, fill factor and energy conversion efficiency) has also been further improved.

[0081] This is because the amine groups at both ends of 1,10-decanediamine hydrochloride can interact well with the perovskite layer, anchored on the surface or grain boundary of the perovskite layer, and more strongly bonded to the perovskite layer, further enhancing the interface stability. At the same time, the anchoring of the amine groups at both ends of 1,10-decanediamine hydrochloride allows the hydrophobic long chain in the middle of 1,10-decanediamine hydrochloride to be more fully exposed to the outside, which can more effectively protect the perovskite layer from being decomposed by water, further improving the moisture resistance of the surface of the perovskite layer.

[0082] Table 3

[0083]

[0084] 1,10-decanediamine hydrochloride (DDADCL) has a large ion size. If it is used as an additive to a perovskite precursor solution (as shown in Comparative Example 5), it will interfere with the normal growth of perovskite crystals. Moreover, during the growth of perovskite crystals, due to the large ion size of 1,10-decanediamine hydrochloride, 1,10-decanediamine hydrochloride is difficult to enter the perovskite lattice, but occupies the grain boundary of the perovskite, which causes the link between the perovskite grains to be not tight enough, making it difficult to form large-sized perovskite grains, and introducing more perovskite grain boundary defects. Therefore, referring to Table 3, whether compared with Example 1 (DDADCL double interface passivation) or Example 2 (DDADCL upper interface passivation), or compared with Comparative Example 2 (DDADCL lower interface passivation), the performance (such as open circuit voltage, short circuit current density, fill factor and energy conversion efficiency) of the perovskite solar cell of Comparative Example 5 (double DDADCL addition passivation) is poor.

[0085] In addition, the near-infrared light irradiated perovskite wet film of publication number CN116056533A cannot achieve the effect of the low-temperature assisted slow annealing process used in the preparation of the perovskite layer of the present invention. This is because: the process of near-infrared light irradiation annealing the perovskite wet film is very fast and cannot delay the nucleation and crystallization process of the perovskite. On the contrary, the present invention also uses a low-temperature assisted slow annealing process when preparing the perovskite layer. At the low temperature stage, the nucleation and crystallization process of the perovskite can be effectively prolonged, the perovskite grain size can be further grown, and the perovskite grain boundary defects can be reduced, thereby improving the carrier transport characteristics.

[0086] Although the preferred embodiments of the present invention have been described, those skilled in the art may make additional changes and modifications to these embodiments once they have learned the basic creative concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications that fall within the scope of the embodiments of the present invention.

[0087] The technical solution provided by the present invention is introduced in detail above. Specific examples are used in this article to illustrate the principle and implementation mode of the present invention. The description of the above embodiments is only used to help understand the method of the present invention and its core idea. At the same time, for those skilled in the art, according to the idea of ​​the present invention, there will be changes in the specific implementation mode and application scope. In summary, the content of this specification should not be understood as limiting the present invention.

Claims

1. A surface passivator for a perovskite solar cell, characterized in that: It is a decanediamine hydrochloride solution, which contains 1,10-decanediamine hydrochloride and isopropanol; Wherein, the concentration of 1,10-decanediamine hydrochloride in the decanediamine hydrochloride solution is 1-3 mg / mL.

2. A passivation method for a perovskite solar cell, characterized in that: The steps include: S1, preparing a substrate having a tin dioxide electron transport layer on the surface; S2, coating the perovskite precursor solution on the surface of the tin dioxide electron transport layer, and preparing a perovskite layer on the surface of the tin dioxide electron transport layer after low temperature assisted slow annealing; S3, applying a decanediamine hydrochloride solution on the surface of the perovskite layer, and annealing to passivate the surface of the perovskite layer; In step S3, the decanediamine hydrochloride solution is a surface passivator for perovskite solar cells according to claim 1.

3. A passivation method for a perovskite solar cell according to claim 2, characterized in that: After step S1, the method further includes the following steps: applying a decanediamine hydrochloride solution on the surface of the tin dioxide electron transport layer, and annealing to passivate the surface of the tin dioxide electron transport layer; wherein the decanediamine hydrochloride solution is a surface passivator for a perovskite solar cell according to claim 1.

4. A passivation method for a perovskite solar cell according to claim 2 or 3, characterized in that: The surface passivation uses 80-100 μL of decanediamine hydrochloride solution; after the surface is coated with the decanediamine hydrochloride solution, annealing is performed at 100-120° C. for 5-10 minutes to complete the surface passivation.

5. A passivation method for a perovskite solar cell according to claim 3, characterized in that: Before the surface of the tin dioxide electron transport layer is passivated, the method further comprises the following steps: the substrate having the tin dioxide electron transport layer on the surface is subjected to ultraviolet ozone treatment for 15-20 minutes.

6. A passivation method for a perovskite solar cell according to claim 2, characterized in that: In step S2, the low temperature assisted slow annealing includes: annealing the perovskite layer coated with the decanediamine hydrochloride solution at 70-80°C for 8-10 minutes, and then annealing at 100-110°C for 8-10 minutes.

7. A passivation method for a perovskite solar cell according to claim 2 or 6, characterized in that: Step S2 specifically includes: coating 40-50 μL of the perovskite precursor solution on the surface of the tin dioxide electron transport layer, and adding 200-220 μL of chlorobenzene anti-solvent 5-7 seconds after the start of coating, and then performing low-temperature assisted slow annealing to prepare the perovskite layer with a thickness of 450-550 nm on the surface of the tin dioxide electron transport layer.

8. A passivation method for a perovskite solar cell according to claim 2, characterized in that: Before step S2, the method further includes a step of preparing a perovskite precursor solution: dissolving weighed lead iodide with a concentration of 1 to 1.6 mol / L and methyl ammonium iodide with a concentration of 1 to 1.6 mol / L in a mixed solvent of dimethyl sulfoxide and dimethylformamide with a volume ratio of 5:1 to 9:1, and stirring for 2 to 3 hours to obtain the perovskite precursor solution.

9. A method for preparing a perovskite solar cell, characterized in that: The method comprises the following preparation steps: Step 1: Cleaning, drying and UV-ozone treating the substrate in sequence; Step 2: using a passivation method for a perovskite solar cell as described in any one of claims 2 to 8 to prepare a perovskite layer and perform surface passivation; Step 3: Prepare a carbon electrode on the surface of the passivated perovskite layer.

10. A perovskite solar cell, characterized in that: It is prepared by the method for preparing a perovskite solar cell as described in claim 9.

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