A method for preparing a perovskite solar cell based on a hole transport layer

Abstract

The present invention relates to the technical field of solar cells, and specifically to a method for preparing a perovskite solar cell based on a hole transport layer, comprising: (1) cleaning a transparent conductive layer; (2) preparing a hole transport layer on the transparent conductive layer using a self-assembled molecular material and an additive, wherein the self-assembled molecular material is a phosphate-based molecule and the additive is a nitrogen-containing polymer material; (3) preparing a perovskite light-absorbing layer on the hole transport layer; (4) preparing a passivation layer on the perovskite light-absorbing layer; (5) preparing an electron transport layer on the passivation layer; (6) preparing an interface buffer layer on the electron transport layer; and (7) preparing an electrode layer on the interface buffer layer. This method significantly optimizes the interface performance of the perovskite solar cell by introducing an additive into the hole transport layer of the perovskite solar cell, thereby reducing the agglomeration of the self-assembled molecules and improving the photoelectric conversion efficiency and stability of the perovskite solar cell.

Description

Technical Field

[0001] The present invention relates to the technical field of solar cells, and in particular to a method for preparing a perovskite solar cell based on a hole transport layer. Background Art

[0002] Metal halide perovskite solar cells (PSCs) have achieved promising power conversion efficiency (PCE) comparable to that of silicon solar cells. The widespread use of self-assembled monolayers (SAMs) as hole transport materials, which have significant hole selectivity, accelerated hole transport, and reduced interface trap density, has led to the rapid development of inverted PSCs in terms of PCE.

[0003] However, traditional self-assembled monolayer materials still have significant shortcomings. First, the hydrophobic nature of the self-assembled monolayer results in poor interfacial contact between the perovskite layer and the self-assembled monolayer, leading to non-radiative recombination and energy loss. Second, due to their weak intermolecular forces, they are prone to aggregation during solution processing, resulting in poor film wettability and coverage, which in turn affects the efficiency of hole collection and photogenerated carrier extraction.

[0004] Therefore, developing a method to achieve a uniform and dense self-assembled monolayer (SAM) layer is an urgent problem to be solved for the successful industrialization of perovskite photovoltaics. Summary of the Invention

[0005] The purpose of the present invention is to overcome the problems of the above-mentioned prior art and provide a method for preparing a perovskite solar cell based on a hole transport layer. By using self-assembled molecular materials in the hole transport layer of the perovskite solar cell and introducing additives (such as 80% ethyl oxypolyethyleneimine) to reduce the agglomeration of the self-assembled molecules, the preparation of a uniform and dense self-assembled monolayer (SAM) is successfully achieved, effectively improving the photoelectric conversion efficiency and stability of the perovskite solar cell.

[0006] The above objectives are achieved through the following technical solutions:

[0007] A method for preparing a perovskite solar cell based on a hole transport layer includes a transparent conductive layer, a hole transport layer, a perovskite light absorption layer, a passivation layer, an electron transport layer, an interface buffer layer, and an electrode layer arranged from bottom to top. The preparation steps are as follows:

[0008] Step (1) cleaning the transparent conductive layer;

[0009] Step (2) preparing a hole transport layer on the transparent conductive layer using a self-assembling molecular material and an additive, wherein the concentration range of the solution of the self-assembling molecular material is 0.2 mg / mL-2 mg / mL, and the concentration range of the additive is 0.055 mg / mL-0.4 mg / mL; the self-assembling molecular material is a phosphate-based molecule, and the additive is a nitrogen-containing polymer material;

[0010] Step (3) preparing a perovskite light absorbing layer on the hole transport layer;

[0011] Step (4) preparing a passivation layer on the perovskite light absorbing layer;

[0012] Step (5) preparing an electron transport layer on the passivation layer;

[0013] Step (6) preparing an interface buffer layer on the electron transport layer;

[0014] Step (7) preparing an electrode layer on the interface buffer layer.

[0015] As a further optimization of the present method, the transparent conductive layer in step (1) is FTO glass, ITO glass, AZO glass, transparent silver nanowire glass, transparent copper nanowire glass, transparent polyaniline glass and a flexible transparent substrate.

[0016] As a further optimization of this method, the phosphate group molecules in step (2) are [2-(3,6-dimethoxy-9H-carbazol-9-yl)ethyl]phosphate (MeO-2PACz), [3-(3,6-dimethoxy-9H-carbazol-9-yl)propyl]phosphate (MeO-3PACz), [6-(3,6-dimethoxy-9H-carbazol-9-yl)hexyl]phosphate (MeO-6PACz), [2-(3,6-dimethyl-9H-carbazol-9-yl)ethyl]phosphate (Me-2PACz), [3-(3,6-dimethyl-9H-carbazol-9-yl)propyl]phosphate (Me-3PACz), [6-(3,6-dimethyl-9H-carbazol-9-yl)hexyl]phosphate (MeO-6PACz), [2-(3,6-dimethyl-9H-carbazol-9-yl)ethyl]phosphate (Me-2PACz), [3-(3,6-dimethyl-9H-carbazol-9-yl)propyl]phosphate (Me-3PACz), [6-(3,6-dimethyl-9H-carbazol-9-yl)hexyl]phosphate (MeO-6PACz). Phosphate (Me-6PACz), [1-(3,6-dimethyl-9H-carbazol-9-yl)methyl]phosphate (Me-1PACz), [4-(3,6-dimethyl-9H-carbazol-9-yl)butyl]phosphate (Me-4PACz), [8-(3,6-dimethyl-9H-carbazol-9-yl)octyl]phosphate (Me-8PACz), [1-(9H-carbazol-9-yl)methyl]phosphate (1PACz), [2-(9H-carbazol-9-yl)ethyl]phosphate (2PACz), [3-(9H-carbazol-9-yl)propyl]phosphate (3PACz), [4-(9H-carbazol-9-yl)butyl]phosphate (4PACz), [6 ... [4-(9H-9'-phenyl-3,3'-dicarbazol-9-yl)butyl] phosphate (4PABCz), [4-(diphenylamino)phenylethyl] phosphate (TPA-2PA), [4-(diphenylamino)phenylpropyl] phosphate (TPA-3PA), [4-(1 [0H-phenothiazin-10-yl)butyl]phosphate (4PAPT), [2-(7H-dibenzocarbazol-7-yl)ethyl]phosphate (2PADCB), [4-(7H-dibenzocarbazol-7-yl)butyl]phosphate (4PADCB), [3-(3,6-dibromo-9H-carbazol-9-yl)propyl]phosphate (2Br-3PACz), [4-(3,6-dibromo-9H-carbazol-9-yl)butyl]phosphate (2Br-4PACz), [6-(3,6-dibromo-9H-carbazol-9-yl)hexyl]phosphate (2Br-6PACz), [1-(3,6-di-tert-butyl-9H-carbazol-9-yl)methyl]phosphate (tBu-1PACz), [2 ...[6-di-tert-butyl-9H-carbazol-9-yl)ethyl]phosphate (tBu-2PACz), [3-(3,6-di-tert-butyl-9H-carbazol-9-yl)propyl]phosphate (tBu-3PACz), [4-(3,6-di-tert-butyl-9H-carbazol-9-yl)butyl]phosphate (tBu-4PACz), [6-(3,6-di-tert-butyl-9H-carbazol-9-yl)hexyl]phosphate (tBu-6PACz), [8-(3,6-di-tert-butyl-9H-carbazol-9-yl)octyl]phosphate (tBu-8PACz), [1-(3,6-diphenyl-9H-carbazol-9-yl)methyl]phosphate (Ph-1PACz), [2-(3,6-diphenyl-9H-carbazol-9-yl)ethyl]phosphate (Ph-2PACz), [ ), [3-(3,6-diphenyl-9H-carbazol-9-yl)propyl]phosphate (Ph-3PACz), [4-(3,6-diphenyl-9H-carbazol-9-yl)butyl]phosphate (Ph-4PACz), [6-(3,6-diphenyl-9H-carbazol-9-yl)hexyl]phosphate (Ph-6PACz), [8-(3,6-diphenyl-9H-carbazol-9-yl)octyl]phosphate (Ph-8PACz), [2-(10H-phenoxazin-10-yl)ethyl]phosphate (2PAPXZ), [4-(3,7-dibromo-10H-phenothiazin-10-yl)butyl]phosphate (2Br-4PAPT), [4-(3,7-dibromo-10H-phenoxazin-10-yl)butyl]phosphate (2Br-4PAPXZ), etc.

[0017] As a further optimization of this method, the nitrogen-containing polymer material in step (2) is one or more of the following: 80% ethylene oxide polyethyleneimine (PEIE), polyethyleneimine, polyimide, diamine-terminated polyethyleneimine, alkyl-oxidized polyethyleneimine, branched polyethyleneimine, hydroxyethylated polyethyleneimine, polypropyleneimine, polysuccinimide, poly(ethylene glycol)-block-polyethyleneimine, and polyethyleneimine hydrochloride, in any type and ratio.

[0018] As a further optimization of this method, the nitrogen-containing polymer material is 80% ethylene oxide polyethyleneimine (PEIE).

[0019] As a further optimization of this method, the structural formula of the material of the perovskite light absorbing layer in step (3) is ABX3; wherein A is selected from CH3NH3 + (MA + )、CH(NH2)2 + (FA + ), Rb + or Cs + Any one or a combination of at least two of: 2+、Ge 2+ 、Sn 2+ Any one or a combination of at least two of; X is selected from C l- Br - or I - Any one or a combination of at least two of .

[0020] As a further optimization of this method, the passivation layer in step (4) is 1,3-propylenediamine iodide (PDAI2).

[0021] As a further optimization of this method, the electron transport layer in step (5) is fullerene (C 60 ) or [6,6]-phenyl-C 61 / C 71- Isomethyl butyrate (PCBM).

[0022] As a further optimization of this method, the interface buffer layer in step (6) is 2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline (BCP) or tin dioxide (SnO2).

[0023] As a further optimization of this method, the electrode layer in step (7) is copper, silver or gold.

[0024] The present invention provides a method for preparing a perovskite solar cell based on a hole transport layer. By introducing additives into the hole transport layer of the perovskite solar cell, the agglomeration of self-assembled molecules is reduced, and the formed hole transport layer is more uniform and dense, resulting in fewer interface defects and better interface contact of the perovskite cell. The photoelectric conversion efficiency and stability of the perovskite solar cell are significantly improved. The single-junction perovskite solar cell based on the PEIE co-adsorption strategy achieves a photoelectric conversion efficiency of 21.69%. The method is applicable to various film preparation methods and can be applied to large-area cells at high throughput, which is of great significance to the industrialization of inverse perovskite photovoltaic technology. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 This is a flow chart of a method for preparing a perovskite solar cell based on a hole transport layer according to the present invention;

[0026] Figure 2 This is a flow chart of the preparation method of a self-assembled monolayer regulated by PEIE in the preparation method of a perovskite solar cell based on a hole transport layer according to the present invention;

[0027] Figure 3This is a graph of the corresponding perovskite cell conversion efficiency when the concentrations of PEIE in the hole transport layer precursor solution are 0.05 mg / mL, 0.1 mg / mL, 0.2 mg / mL, and 0.4 mg / mL, respectively, in the preparation method of a perovskite solar cell based on a hole transport layer described in the present invention (Example 1).

[0028] Figure 4 The hole transport layer prepared under the optimal conditions in the preparation method of a perovskite solar cell based on a hole transport layer described in the present invention (Example 2) is compared with the hole transport layer prepared by the traditional spin coating method (Comparative Example 1). They are respectively applied to complete perovskite cells, and their VOC, JSC, FF and PCE statistical data comparison charts are obtained.

[0029] Figure 5 Comparison of the JV curves of the optimal efficiency cells obtained under the optimal conditions for preparing the hole transport layer in the preparation method of a perovskite solar cell based on a hole transport layer according to the present invention (Example 2) and the hole transport layer prepared by the traditional spin coating method (Comparative Example 1). DETAILED DESCRIPTION

[0030] The present invention will be further described in detail below with reference to the accompanying drawings and examples. The described embodiments are only some embodiments of the present invention, not all embodiments. All other embodiments derived by persons of ordinary skill in the art based on the embodiments of the present invention without inventive effort shall fall within the scope of protection of the present invention.

[0031] like Figure 1 As shown, this solution provides a method for preparing a perovskite solar cell based on a hole transport layer, including a transparent conductive layer, a hole transport layer, a perovskite light absorbing layer, a passivation layer, an electron transport layer, an interface buffer layer and an electrode layer arranged from bottom to top. The preparation steps are as follows:

[0032] Step (1) Cleaning the transparent conductive layer, which provides support for subsequent layers and serves as a channel for charge transfer to collect photogenerated current;

[0033] Step (2) preparing a hole transport layer on the transparent conductive layer using a self-assembled molecular material and an additive, wherein the concentration range of the solution of the self-assembled molecular material is 0.2 mg / mL-2 mg / mL, and the concentration range of the additive is 0.055 mg / mL-0.4 mg / mL; the self-assembled molecular material is a phosphate-based molecule, and the additive is a nitrogen-containing polymer material; the main function of this layer is to transport holes and block electrons, reduce the agglomeration of the self-assembled molecules, form a uniform and dense film, reduce interface defects, improve interface contact, and promote the efficiency of hole collection and extraction of photogenerated carriers;

[0034] Step (3) preparing a perovskite light-absorbing layer on the hole transport layer; this layer is the core part of the battery, responsible for absorbing sunlight and generating photogenerated electron-hole pairs;

[0035] Step (4) preparing a passivation layer on the perovskite light absorbing layer; the function of this layer is to passivate the defects on the surface of the perovskite light absorbing layer, reduce non-radiative recombination, and improve battery performance;

[0036] Step (5) preparing an electron transport layer on the passivation layer; the main function of which is to transport electrons and block holes, so that electrons can be smoothly transported to the electrode;

[0037] Step (6) preparing an interface buffer layer on the electron transport layer; this can optimize the interface performance between the electron transport layer and the electrode layer, reduce charge recombination, and improve the stability and efficiency of the battery;

[0038] Step (7) An electrode layer is prepared on the interface buffer layer; the electrode layer is used to collect electrons transmitted from the electron transport layer and is connected to an external circuit to form a complete circuit loop, so that the battery can output electrical energy to the outside.

[0039] It should be noted that the types of perovskite solar cells in this scheme include single-cell perovskite solar cells, hole collection layers of broadband perovskite parts in perovskite / crystalline silicon tandem solar cells; and perovskite / perovskite tandem solar cells, which serve as hole transport layers for wide-bandgap and narrow-bandgap cells, respectively.

[0040] The preparation methods of the hole transport layer and other functional layers on the transparent conductive layer include but are not limited to spin coating, doctor blade coating, slit coating, screen printing, thermal evaporation, ion beam deposition, magnetron sputtering deposition, atomic layer deposition, etc.

[0041] Specifically, when the hole transport layer is prepared on the transparent conductive layer by spin coating in step (2), the spin coating speed is 3000 rpm-7000 rpm, the acceleration is 4000 rpm / s-8000 rpm / s, and the spin coating time is 10s-30s; in addition, the annealing temperature is 80°C-120°C, the annealing time is 5 min-15 min, and the annealing environment is in an air environment or in a glove box protected by inert gas.

[0042] Step (1) of the present method is specifically as follows: ultrasonically cleaning the transparent conductive layer in the order of acetone, IPA, acetone, and IPA for 20 minutes, drying at 65°C, and treating with ultraviolet ozone for 15 minutes to obtain a clean transparent conductive layer. The transparent conductive layer is one of FTO glass, ITO glass, AZO glass, transparent silver nanowire glass, transparent copper nanowire glass, transparent polyaniline glass, and a flexible transparent substrate.

[0043] like Figure 2 As shown, step (2) of the present method is specifically as follows: mixing the self-assembling molecular material and the additive in a solvent to prepare a hole transport layer precursor solution, and preparing the hole transport layer on the transparent conductive layer by spin coating. The spin coating speed is 3000 rpm-7000 rpm, the acceleration is 4000 rpm / s-8000 rpm / s, and the spin coating time is 10 s-30 s; in addition, the annealing temperature is 80 ℃-120 ℃, the annealing time is 5 min-15 min, and the annealing environment is in air or in an inert gas protected glove box.

[0044] Among them, the phosphate-based molecules used as self-assembling molecular materials include but are not limited to [2-(3,6-dimethoxy-9H-carbazol-9-yl)ethyl]phosphate (MeO-2PACz), [3-(3,6-dimethoxy-9H-carbazol-9-yl)propyl]phosphate (MeO-3PACz), [6-(3,6-dimethoxy-9H-carbazol-9-yl)hexyl]phosphate (MeO-6PACz), [2-(3,6-dimethyl-9H-carbazol-9-yl)ethyl]phosphate (Me-2PACz), [3-(3,6-dimethyl-9H-carbazol-9-yl)propyl]phosphate (Me-3PACz), [6-(3,6-dimethyl-9H-carbazol-9-yl)hexyl]phosphate Phosphate (Me-6PACz), [1-(3,6-dimethyl-9H-carbazol-9-yl)methyl]phosphate (Me-1PACz), [4-(3,6-dimethyl-9H-carbazol-9-yl)butyl]phosphate (Me-4PACz), [8-(3,6-dimethyl-9H-carbazol-9-yl)octyl]phosphate (Me-8PACz), [1-(9H-carbazol-9-yl)methyl]phosphate (1PACz), [2-(9H-carbazol-9-yl)ethyl]phosphate (2PACz), [3-(9H-carbazol-9-yl)propyl]phosphate (3PACz), [4-(9H-carbazol-9-yl)butyl]phosphate (4PACz), [6 ... )hexyl] phosphate (6PACz), [8-(9H-carbazol-9-yl)octyl] phosphate (8PACz), [4-(N,N-bis(4-methoxyphenylamino)phenyl)propyl] phosphate (MeO-TPA-3PA), 2,3,4,5,6-pentafluorobenzyl phosphate (F5BPA), [2-(9H-9'-phenyl-3,3'-dicarbazol-9-yl)ethyl] phosphate (2PABCz), [4-(9H-9'-phenyl-3,3'-dicarbazol-9-yl)butyl] phosphate (4PABCz), [4-(diphenylamino)phenylethyl] phosphate (TPA-2PA), [4-(diphenylamino)phenylpropyl] phosphate (TPA-3PA), [4-(1 [0H-phenothiazin-10-yl)butyl]phosphate (4PAPT), [2-(7H-dibenzocarbazol-7-yl)ethyl]phosphate (2PADCB), [4-(7H-dibenzocarbazol-7-yl)butyl]phosphate (4PADCB), [3-(3,6-dibromo-9H-carbazol-9-yl)propyl]phosphate (2Br-3PACz), [4-(3,6-dibromo-9H-carbazol-9-yl)butyl]phosphate (2Br-4PACz), [6-(3,6-dibromo-9H-carbazol-9-yl)hexyl]phosphate (2Br-6PACz), [1-(3,6-di-tert-butyl-9H-carbazol-9-yl)methyl]phosphate (tBu-1PACz), [2 ...[6-di-tert-butyl-9H-carbazol-9-yl)ethyl]phosphate (tBu-2PACz), [3-(3,6-di-tert-butyl-9H-carbazol-9-yl)propyl]phosphate (tBu-3PACz), [4-(3,6-di-tert-butyl-9H-carbazol-9-yl)butyl]phosphate (tBu-4PACz), [6-(3,6-di-tert-butyl-9H-carbazol-9-yl)hexyl]phosphate (tBu-6PACz), [8-(3,6-di-tert-butyl-9H-carbazol-9-yl)octyl]phosphate (tBu-8PACz), [1-(3,6-diphenyl-9H-carbazol-9-yl)methyl]phosphate (Ph-1PACz), [2-(3,6-diphenyl-9H-carbazol-9-yl)ethyl]phosphate (Ph-2PACz), [ ), [3-(3,6-diphenyl-9H-carbazol-9-yl)propyl]phosphate (Ph-3PACz), [4-(3,6-diphenyl-9H-carbazol-9-yl)butyl]phosphate (Ph-4PACz), [6-(3,6-diphenyl-9H-carbazol-9-yl)hexyl]phosphate (Ph-6PACz), [8-(3,6-diphenyl-9H-carbazol-9-yl)octyl]phosphate (Ph-8PACz), [2-(10H-phenoxazin-10-yl)ethyl]phosphate (2PAPXZ), [4-(3,7-dibromo-10H-phenothiazin-10-yl)butyl]phosphate (2Br-4PAPT), [4-(3,7-dibromo-10H-phenoxazin-10-yl)butyl]phosphate (2Br-4PAPXZ), etc.

[0045] The nitrogen-containing polymer material used as an additive includes, but is not limited to, 80% ethylene oxide polyethyleneimine (PEIE), polyethyleneimine, polyimide, diamine-terminated polyethyleneimine, alkyl-oxidized polyethyleneimine, branched polyethyleneimine, hydroxyethylated polyethyleneimine, polypropyleneimine, polysuccinimide, poly(ethylene glycol)-block-polyethyleneimine, and polyethyleneimine hydrochloride, one or more of which are selected from the group consisting of any type and combination of any proportion.

[0046] In the precursor solution for preparing the hole transport layer, the concentration range of the self-assembling molecular material solution is 0.2 mg / mL-2 mg / mL, and the concentration range of the additive is 0.055 mg / mL-0.4 mg / mL.

[0047] It should be noted that the nitrogen-containing polymer material in this embodiment is preferably 80% ethylene oxide polyethyleneimine (PEIE).

[0048] The general structural formula of the material of the perovskite light absorbing layer in step (3) of this method is ABX3;

[0049] Wherein, A is selected from CH3NH3 + (MA+ ) CH(NH2)2 + (FA + ) Rb + or Cs + or a combination of any one or at least two of them;

[0050] B is selected from Pb 2+ , Ge 2+ , Sn 2+ or a combination of any one or at least two of them;

[0051] X is selected from Cl - , Br - or I - or a combination of any one or at least two of them.

[0052] Mix the perovskite precursor materials in a mixed solvent such as DMF:DMSO to prepare a perovskite precursor solution, and prepare a perovskite light-absorbing layer on the hole transport layer by one of the methods such as spin coating, blade coating, slot die coating, screen printing, thermal evaporation, ion beam deposition, magnetron sputtering deposition, atomic layer deposition, etc. The thickness range of the perovskite light-absorbing layer is adjusted according to different materials and application requirements. For example, for perovskite materials with a bandgap width range of 1.49 - 1.75 eV, the thickness range is 400 - 1000 nm.

[0053] The materials of the perovskite light-absorbing layer described in this embodiment include MAPbI3, FAPbI3, MA x FA (1-x) PbI3 (0 < x < 1), Cs x MA y FA z PbI3 (x + y + z = 1), with a bandgap width range of 1.49 - 1.75 eV and a thickness range of 400 nm - 1000 nm.

[0054] The materials of the perovskite light-absorbing layer may include wide-bandgap perovskites with a bandgap width range of 1.60 - 1.8 eV, including Cs x MA y FA z PbI 3-n Br n (x + y + z = 1, 0 < n < 3), with a thickness range of 200 nm - 1000 nm;

[0055] The materials of the perovskite light-absorbing layer may also include narrow-bandgap perovskites with a bandgap width range of 1.20 - 1.50 eV, including C sx MA y FA z SnPb nI3 (x + y + z = 1, 0 < n < 3), with a thickness range of 500 nm - 2000 nm.

[0056] It should be noted that the perovskite solar cells using the SAM layer prepared by this method include not only the single - cell of various different perovskites described above, but also the HTL part of the wide - bandgap cell in the all - perovskite tandem cell. The structure of the all - perovskite tandem cell is conductive glass / SAM layer / wide - bandgap perovskite / electron transport layer / intermediate layer / hole transport layer / narrow - bandgap perovskite light - absorbing layer / electron transport layer / electrode.

[0057] The hole transport layer prepared by this method also includes the HTL part of the narrow - bandgap cell in the all - perovskite tandem cell. The structure of the all - perovskite tandem cell is conductive glass / hole transport layer / wide - bandgap perovskite / electron transport layer / intermediate layer / SAM layer / narrow - bandgap perovskite light - absorbing layer / electron transport layer / electrode.

[0058] The perovskite solar cells using the hole transport layer prepared by this method also include the HTL part of the wide - bandgap cell in the perovskite / silicon tandem cell. The structure of the perovskite / silicon cell is silicon cell / intermediate layer / SAM layer / wide - bandgap perovskite / electron transport layer / electrode.

[0059] Step (4) of this method is specifically: dissolving the passivation layer material in an appropriate solvent, and preparing the passivation layer on the perovskite light - absorbing layer by spin - coating or other methods.

[0060] Among them, the passivation layer is 1,3 - propanediamine iodide (PDAI2), the solvent is a mixed solvent of IPA and DMSO (IPA:DMSO = 99:1 v:v). The passivation solvent is spin - coated on the perovskite light - absorbing layer at a speed of 5000 rpm for 20 seconds, and then annealed at 110 °C for 10 minutes.

[0061] The electron transport layer in step (5) of this method is fullerene (C 60 ) or [6,6] - phenyl - C 61 / C 71- butyl isobutyrate (PCBM), and is prepared by thermal evaporation, spin - coating or other methods.

[0062] The interface buffer layer in step (6) of this method is 2,9 - dimethyl - 4,7 - diphenyl - 1,10 - phenanthroline (BCP) or tin dioxide (SnO2); and is prepared by thermal evaporation or other methods. For example, deposit SnO2 with a thickness of 20 nm.

[0063] The electrode layer in step (7) of this method is copper, silver or gold, and is prepared by thermal evaporation or other methods. For example, deposit Cu with a thickness of 80 nm. Example 1

[0064] This embodiment provides a method for preparing a perovskite solar cell based on a hole transport layer, as follows:

[0065] Cleaning the transparent conductive layer: The ITO or FTO substrate glass was ultrasonically cleaned in acetone, IPA, acetone, and IPA in the order of 20 minutes, dried at 65°C, and treated with ultraviolet ozone for 15 minutes to obtain a clean transparent conductive layer.

[0066] Preparation of hole transport layer: MeO-2PACz and PEIE were mixed in ethanol solvent (the concentration of MeO-2PACz in ethanol solution was 0.75 mg / mL), and four sets of hole transport layer precursor solutions with PEIE concentrations of 0.05 mg / mL, 0.1 mg / mL, 0.2 mg / mL, and 0.4 mg / mL were prepared as controls and transferred to a spin coater. 300 μL of the precursor was spin-coated on the transparent conductive layer at 5000 rpm for 20 seconds, followed by annealing at 100°C for 10 minutes. Figure 2 As shown, the key steps from transparent conductive layer cleaning to hole transport layer preparation are demonstrated, including precursor solution preparation, spin coating and annealing processes.

[0067] Preparation of perovskite light-absorbing layer: The chemical formula of perovskite material is Cs 0.05 MA 0.05 FA 0.90 PbBr 0.1 I 2.9 CsI, FAI, MABr, MACl, PbBr2 and PbI2 were mixed in DMF:DMSO mixed solvent (4:1 v:v) to prepare a 1.4 M perovskite precursor solution with the chemical formula of Cs 0.05 MA 0.05 FA 0.90 PbBr 0.1 I 2.9 Before deposition, 10 mol% MACl, 1 mg / mL GuaBCl, 1 mg / mL PMACl, and 2 mg / mL PbCl2 were added to the perovskite precursor. After stirring for more than 6 hours, the mixture was transferred to a spin coater. 300 μL of the perovskite precursor was dropped onto the hole transport layer and spin-coated at 1000 rpm for 5 seconds, then 3000 rpm for 30 seconds. During the final 15 seconds, 600 μL of chlorobenzene was added as an antisolvent. The perovskite film was then annealed at 110°C for 20 minutes.

[0068] Prepare the passivation layer: Dissolve 1 mg / mL of PDAI2 in a mixture of IPA and DMSO (IPA:DMSO = 99:1 v:v). Spin-coat the passivation solvent onto the perovskite absorber layer at 5000 rpm for 20 seconds, followed by annealing at 110°C for 10 minutes.

[0069] Preparation of electron transport layer, interface buffer layer and electrode layer: The film was transferred to a thermal evaporator and C was deposited with thicknesses of 18 nm, 20 nm and 80 nm respectively under high vacuum (<5×10-5Pa). 60 , SnO2 and Cu. Example 2

[0070] This embodiment provides a perovskite solar cell based on a hole transport layer. The only difference between this embodiment and the aforementioned embodiment 1 is that the concentration of PEIE in the hole transport layer precursor solution is only 0.2 mg / mL. The other materials, structures and preparation methods are the same as those in embodiment 1.

[0071] Comparative Example 1

[0072] This comparative example provides a perovskite solar cell, which differs from the aforementioned Example 2 only in that the hole transport layer precursor solution contains only MeO-2PACz at a concentration of 0.75 mg / mL, and is obtained by spin coating at a speed of 5000 rpm for 30 seconds, followed by annealing in air at 110°C for 10 minutes, and then transferred to a glove box for the remaining steps. The other materials, structures, and preparation methods are the same as those in Example 2.

[0073] Performance Testing

[0074] The open circuit voltage (VOC), short circuit current (JSC), fill factor (FF) and initial photoelectric conversion efficiency (PCE) of the perovskite cell provided in Example 1 were tested. The test results are as follows: Figure 3 The figure shows the key steps from transparent conductive layer cleaning to hole transport layer preparation, including precursor solution preparation, spin coating, and annealing. The perovskite cell provided by this method achieved the highest average power conversion efficiency at a PEIE concentration of 0.2 mg / mL, while also significantly improving the FF of the device. This indicates that PEIE facilitates the construction of a more uniform and dense buried interface, significantly reducing non-radiative recombination and leakage current at the buried interface, thereby improving the efficiency of the solar cell.

[0075] At the same time, in this method, the photovoltaic parameters of the single-junction perovskite solar cell based on the PEIE co-adsorption strategy are greatly improved compared with Comparative Example 1, achieving a photoelectric conversion efficiency of 21.69%.

[0076] like Figure 4As shown in the figure, a comparison was made between the optimal conditions for preparing a hole transport layer using this method (Example 2) and a hole transport layer prepared using a conventional spin coating method (Comparative Example 1). These methods were applied to complete perovskite cells, and statistical comparisons of their VOC, JSC, FF, and PCE were obtained. The data demonstrate that the photovoltaic parameters of the cell prepared using the method of the present invention were significantly improved compared to those in Comparative Example 1.

[0077] like Figure 5 Figure 2 shows a comparison of the JV curves of the optimal efficiency cell produced under the optimal conditions for preparing the hole transport layer using this method (Example 2) and using a hole transport layer prepared using a conventional spin coating method (Comparative Example 1). The curves demonstrate that the cell prepared using the method of the present invention has higher short-circuit current and open-circuit voltage, as well as a better fill factor, resulting in higher photoelectric conversion efficiency.

[0078] The above description is only for explaining the embodiments of the present invention and is not intended to limit the present invention. For those skilled in the art, any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A method for preparing a perovskite solar cell based on a hole transport layer, characterized in that: The process includes a transparent conductive layer, a hole transport layer, a perovskite light absorption layer, a passivation layer, an electron transport layer, an interface buffer layer, and an electrode layer arranged from bottom to top. The preparation steps are as follows: Step (1) cleaning the transparent conductive layer; Step (2) preparing a hole transport layer on the transparent conductive layer using a self-assembling molecular material and an additive, wherein the concentration range of the solution of the self-assembling molecular material is 0.2 mg / mL-2 mg / mL, and the concentration range of the additive is 0.055 mg / mL-0.4 mg / mL; the self-assembling molecular material is a phosphate-based molecule, and the additive is a nitrogen-containing polymer material; the nitrogen-containing polymer material is one or more of the following: 80% ethylene oxide polyethyleneimine (PEIE), polyethyleneimine, polyimide, diamine-terminated polyethyleneimine, alkyl-oxidized polyethyleneimine, branched polyethyleneimine, hydroxyethylated polyethyleneimine, polypropyleneimine, polysuccinimide, poly(ethylene glycol)-block-polyethyleneimine, and polyethyleneimine hydrochloride, in any type and ratio; Step (3) preparing a perovskite light absorbing layer on the hole transport layer; Step (4) preparing a passivation layer on the perovskite light absorbing layer; Step (5) preparing an electron transport layer on the passivation layer; Step (6) preparing an interface buffer layer on the electron transport layer; Step (7) preparing an electrode layer on the interface buffer layer.

2. The method for preparing a perovskite solar cell based on a hole transport layer according to claim 1, characterized in that: The transparent conductive layer in step (1) is FTO glass, ITO glass, AZO glass, transparent silver nanowire glass, transparent copper nanowire glass, transparent polyaniline glass and a flexible transparent substrate.

3. The method for preparing a perovskite solar cell based on a hole transport layer according to claim 2, characterized in that: The phosphate group molecules in step (2) are [2-(3,6-dimethoxy-9H-carbazole-9-yl)ethyl]phosphate (MeO-2PACz), [3-(3,6-dimethoxy-9H-carbazole-9-yl)propyl]phosphate (MeO-3PACz), [6-(3,6-dimethoxy-9H-carbazole-9-yl)hexyl]phosphate (MeO-6PACz), [2-(3,6-dimethyl-9H-carbazole-9-yl)ethyl]phosphate (Me-2PACz), [3-(3,6-dimethyl-9H-carbazole-9-yl)propyl]phosphate (Me-3PACz), [6-(3,6-dimethyl-9H-carbazole-9-yl)hexyl]phosphate (Me-6PACz). Cz), [1-(3,6-dimethyl-9H-carbazol-9-yl)methyl]phosphate (Me-1PACz), [4-(3,6-dimethyl-9H-carbazol-9-yl)butyl]phosphate (Me-4PACz), [8-(3,6-dimethyl-9H-carbazol-9-yl)octyl]phosphate (Me-8PACz), [1-(9H-carbazol-9-yl)methyl]phosphate (1PACz), [2-(9H-carbazol-9-yl)ethyl]phosphate (2PACz), [3-(9H-carbazol-9-yl)propyl]phosphate (3PACz), [4-(9H-carbazol-9-yl)butyl]phosphate (4PACz), [6-(9H-carbazol-9-yl)hexyl]phosphate Phosphoric acid (6PACz), [8-(9H-carbazol-9-yl)octyl] phosphate (8PACz), [4-(N,N-bis(4-methoxyphenylamino)phenyl)propyl] phosphate (MeO-TPA-3PA), 2,3,4,5,6-pentafluorobenzyl phosphate (F5BPA), [2-(9H-9'-phenyl-3,3'-dicarbazol-9-yl)ethyl] phosphate (2PABCz), [4-(9H-9'-phenyl-3,3'-dicarbazol-9-yl)butyl] phosphate (4PABCz), [4-(diphenylamino)phenylethyl] phosphate (TPA-2PA), [4-(diphenylamino)phenylpropyl] phosphate (TPA-3PA), [4-(10H- Phosphothiazin-10-yl)butyl]phosphate (4PAPT), [2-(7H-dibenzocarbazol-7-yl)ethyl]phosphate (2PADCB), [4-(7H-dibenzocarbazol-7-yl)butyl]phosphate (4PADCB), [3-(3,6-dibromo-9H-carbazol-9-yl)propyl]phosphate (2Br-3PACz), [4-(3,6-dibromo-9H-carbazol-9-yl)butyl]phosphate (2Br-4PACz), [6-(3,6-dibromo-9H-carbazol-9-yl)hexyl]phosphate (2Br-6PACz), [1-(3,6-di-tert-butyl-9H-carbazol-9-yl)methyl]phosphate (tBu-1PACz), [2 ...[6-di-tert-butyl-9H-carbazol-9-yl)ethyl]phosphate (tBu-2PACz), [3-(3,6-di-tert-butyl-9H-carbazol-9-yl)propyl]phosphate (tBu-3PACz), [4-(3,6-di-tert-butyl-9H-carbazol-9-yl)butyl]phosphate (tBu-4PACz), [6-(3,6-di-tert-butyl-9H-carbazol-9-yl)hexyl]phosphate (tBu-6PACz), [8-(3,6-di-tert-butyl-9H-carbazol-9-yl)octyl]phosphate (tBu-8PACz), [1-(3,6-diphenyl-9H-carbazol-9-yl)methyl]phosphate (Ph-1PACz), [2-(3,6-diphenyl-9H-carbazol-9-yl)ethyl]phosphate (Ph-2PACz), [ ), [3-(3,6-diphenyl-9H-carbazol-9-yl)propyl]phosphate (Ph-3PACz), [4-(3,6-diphenyl-9H-carbazol-9-yl)butyl]phosphate (Ph-4PACz), [6-(3,6-diphenyl-9H-carbazol-9-yl)hexyl]phosphate (Ph-6PACz), [8-(3,6-diphenyl-9H-carbazol-9-yl)octyl]phosphate (Ph-8PACz), [2-(10H-phenoxazin-10-yl)ethyl]phosphate (2PAPXZ), [4-(3,7-dibromo-10H-phenothiazin-10-yl)butyl]phosphate (2Br-4PAPT), [4-(3,7-dibromo-10H-phenoxazin-10-yl)butyl]phosphate (2Br-4PAPXZ). , 4. The method for preparing a perovskite solar cell based on a hole transport layer according to claim 1, characterized in that: The general structural formula of the material of the perovskite light absorbing layer in step (3) is ABX3; Wherein, A is selected from CH3NH3 + (MA + )、CH(NH2)2 + (FA + ), Rb + or Cs + Any one or a combination of at least two of the following: B is selected from Pb 2+ 、Ge 2+ 、Sn 2+ Any one or a combination of at least two of the following: X is selected from Cl - Br - or I - Any one or a combination of at least two of .

5. The method for preparing a perovskite solar cell based on a hole transport layer according to claim 1, characterized in that: The passivation layer in step (4) is 1,3-propylenediamine iodide (PDAI2).

6. The method for preparing a perovskite solar cell based on a hole transport layer according to claim 1, characterized in that: The electron transport layer in step (5) is fullerene (C 60 ) or [6,6]-phenyl-C 61 / C 71- Isomethyl butyrate (PCBM).

7. The method for preparing a perovskite solar cell based on a hole transport layer according to claim 1, characterized in that: The interface buffer layer in step (6) is 2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline (BCP) or tin dioxide (SnO2).

8. The method for preparing a perovskite solar cell based on a hole transport layer according to claim 1, characterized in that: The electrode layer in step (7) is copper, silver or gold.

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