A preparation method of perovskite solar cell based on interface modification

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 interface modification, 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 concentration range of the self-assembled molecular material solution is 0.2 mg / mL-2 mg / mL, and the concentration range of the dipole molecule additive is 0.5 mg / mL-2.5 mg / mL; (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. The method introduces a dipole molecule additive into the hole transport layer of the perovskite solar cell, so that the SAM micelles in the solution are transformed from a cross-linked fiber-like structure to a smaller block arrangement, thereby improving the quality of the hole transport layer film and improving the hole transport efficiency.

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 interface modification. Background Art

[0002] In recent years, inverted perovskite solar cells (PSCs) have attracted widespread attention due to their low cost and excellent interfacial hole transport performance. Their certified power conversion efficiency (PCE) has exceeded 26%, but has not yet reached the Shockley-Queisser (SQ) limit. Self-assembled monolayers (SAMs), a key component of inverted PSCs, are primarily composed of anchor groups that bind to the indium tin oxide substrate, end groups that regulate surface properties, and spacer groups.

[0003] However, SAMs in the prior art have the following significant drawbacks:

[0004] SAM molecular agglomeration effect: The amphiphilicity of SAM and its poor wettability to the perovskite precursor solution cause it to easily form agglomerations in the solution, seriously affecting the optimal contact of the perovskite / hole transport layer (HTL) buried interface, thereby destroying the crystallization quality of the perovskite film.

[0005] Energy barrier of micelle disassembly: The disassembly of SAM micelles will generate additional energy barriers during their binding to the substrate, hindering hole transport.

[0006] Insufficient density of the SAM structure: Due to the rough substrate surface and the limitations of the commonly used wet deposition method, it is difficult to stably form a dense SAM structure, which inevitably leads to defect formation, especially in areas with low SAM coverage.

[0007] Therefore, how to develop a uniform and dense SAM layer to improve interface contact and hole transport efficiency has become a key challenge that needs to be urgently addressed in the field of perovskite photovoltaics. Summary of the Invention

[0008] The purpose of the present invention is to overcome the problems of the above-mentioned prior art and provide a method for preparing perovskite solar cells based on interface modification. By introducing dipole molecule additives into the self-assembled monolayer of the perovskite solar cell, the SAM micelles in the solution are transformed from a fiber-like structure to a smaller block arrangement, thereby improving the quality of the hole transport layer film and improving the hole transport efficiency.

[0009] The above objectives are achieved through the following technical solutions:

[0010] A method for preparing a perovskite solar cell based on interface modification 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:

[0011] Step (1) cleaning the transparent conductive layer;

[0012] Step (2) A hole transport layer is prepared on the transparent conductive layer using a self-assembling molecular material and a dipole molecule additive. 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 dipole molecule additive is 0.5 mg / mL-2.5 mg / mL; the self-assembling molecular material is a phosphate-based molecule, and the dipole molecule additive is 4-trifluoromethylphenylammonium chloride (CF3-PhACl), 4-methoxyphenethylammonium iodide (MeO-PEAI), 4-hydroxyphenethylammonium iodide ammonium (OH-PEAI), 3-trifluoromethylphenethylammonium iodide (CF3-PEAI), 4-methoxyphenylammonium iodide (MeO-PhAI), 4-trifluoromethyl-benzylammonium chloride, 4-(trifluoromethyl)phenethyl bromide, 2-(trifluoromethyl)phenethyl bromide, 1-(2-bromoethyl)-3-(trifluoromethyl)benzene, 1-(3-trifluoromethylphenyl)ethyl bromide, p-trifluoromethylbenzonitrile, 4-chlorophenethylammonium chloride, 3-methoxyphenethylammonium iodide, 2-methoxyphenethylammonium iodide, 4-methoxy-phenylammonium iodide, 4-fluorobenzylammonium iodide;

[0013] Step (3) preparing a perovskite light absorbing layer on the hole transport layer;

[0014] Step (4) preparing a passivation layer on the perovskite light absorbing layer;

[0015] Step (5) preparing an electron transport layer on the passivation layer;

[0016] Step (6) preparing an interface buffer layer on the electron transport layer;

[0017] Step (7) preparing an electrode layer on the interface buffer layer.

[0018] As a further optimization of the present method, the step (2) is specifically as follows: the self-assembly molecular material and the dipole molecule additive are mixed in an ethanol solvent to prepare a hole transport layer precursor solution, and the hole transport layer is prepared on the transparent conductive layer by spin coating; the spin coating speed is 3000rpm-7000rpm, the acceleration is 4000rpm / s-8000rpm / s, and the spin coating time is 10s-30s; in addition, the annealing temperature is 80℃-120℃, 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.

[0019] As a further optimization of this method, the self-assembling molecular materials in step (2) include [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 ... e-2PACz), [3-(3,6-dimethyl-9H-carbazol-9-yl)propyl]phosphoric acid (Me-3PACz), [6-(3,6-dimethyl-9H-carbazol-9-yl)hexyl]phosphoric acid (Me-6PACz), [1-(3,6-dimethyl-9H-carbazol-9-yl)methyl]phosphoric acid (Me-1PACz), [4-(3,6-dimethyl-9H-carbazol-9-yl)butyl]phosphoric acid (Me-4PACz), [8-(3,6-dimethyl-9H-carbazol-9-yl)butyl]phosphoric acid (Me-4 ... [-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 (6PACz), [8-(9H-carbazol-9-yl) octyl] phosphate ( ... ACz), [4-(N,N-bis(4-methoxyphenylamino)phenyl)propyl]phosphoric acid (MeO-TPA-3PA), 2,3,4,5,6-pentafluorobenzylphosphoric acid (F5BPA), [2-(9H-9'-phenyl-3,3'-biscarbazol-9-yl)ethyl]phosphoric acid (2PABCz), [4-(9H-9'-phenyl-3,3'-biscarbazol-9-yl)butyl]phosphoric acid (4PABCz), [4-(diphenylamino)phenethyl]phosphoric acid (TPA-2PA), [4-(Diphenylamino)phenylpropyl]phosphate (TPA-3PA), [4-(10H-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-(3,6-di-tert-butyl-9H-carbazol-9-yl)methyl]phosphate (tBu-1PACz), [2-(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-(3,6-di-tert-butyl-9H-carbazol-9-yl)methyl]phosphate (tBu-1PACz), [2-(3,6-dibromo-9H-carbazol-9-yl)[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). ,

[0020] As a further optimization of this method, the concentration of the self-assembling molecular material in the ethanol solvent is 0.75 mg / mL, and the concentration of the dipole molecule additive in the ethanol solvent is 1.5 mg / mL;

[0021] The self-assembling molecular material is [2-(3,6-dimethoxy-9H-carbazole-9-yl)ethyl]phosphoric acid (MeO-2PACz);

[0022] The dipole molecule additive is 4-trifluoromethylphenylammonium chloride (CF3-PhACl).

[0023] As a further optimization of the method, the self-assembled molecular material forms SAM micelles in solution. The size of the SAM micelles is 10-1000 nm, and the shapes include square, needle, sphere, island, network, layer, dendrite, rod and amorphous.

[0024] As a further optimization of the present method, the step (1) 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.

[0025] As a further optimization of this method, 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 flexible transparent substrate.

[0026] As a further optimization of this method, the structural general formula of the material of the perovskite light-absorbing layer in step (3) is ABX3;

[0027] Among them, A is selected from CH3NH3 + (MA + ), CH(NH2)2 + (FA + ), Rb + or Cs + or any combination of at least two of them;

[0028] B is selected from Pb 2+ , Ge 2+ , Sn 2+ or any combination of at least two of them;

[0029] X is selected from Cl - , Br - or I - or any combination of at least two of them.

[0030] As a further optimization of this method, the material of the perovskite light-absorbing layer includes MAPbI3, FAPbI3, MA x FA [[ID=?]] (1-x) PbI3 (0 < x < 1), Cs x MA y FA z PbI3 (x + y + z = 1), the bandgap width ranges from 1.49 - 1.75 eV, and the thickness ranges from 400 nm to 1000 nm.

[0031] As a further optimization of this method, the material of the perovskite light-absorbing layer includes wide-bandgap perovskite, the bandgap width ranges from 1.60 - 1.8 eV, including Cs x MA y [[ID=?]] z PbI 3-n Br n (x + y + z = 1, 0 < n < 3), the thickness ranges from 200 nm to 1000 nm; or, the material of the perovskite light-absorbing layer includes narrow-bandgap perovskite, the bandgap width ranges from 1.20 - 1.50 eV, including C sx MA y FA z SnPb n It seems there are some missing tags in the original text which might be causing issues in the translation. Please check and correct if possible. Also, the "?" marks indicate where there might be an issue with the tags in the original for proper translation.I3 (x + y + z = 1, 0 < n < 3), with a thickness range of 500 nm - 2000 nm.

[0032] A method for preparing a perovskite solar cell based on interface modification provided by the present invention effectively improves the aggregation effect and micelle morphology of SAM molecules by introducing a dipole molecule additive into the hole transport layer of the perovskite solar cell, thereby increasing the coverage rate, smoothness and orderliness of SAM on the substrate, and thus significantly enhancing the photoelectric conversion efficiency and stability of the perovskite solar cell. More importantly, this method has a simple process and is completely compatible with the existing solution preparation process, especially suitable for the large-scale production of large-area perovskite solar cells, providing important technical support for promoting the industrialization process of perovskite photovoltaic technology. Specifically, it includes:

[0033] (1) Improving the SAM micelle morphology: By introducing a dipole molecule additive (such as CF3-PhACl), the SAM micelles in the solution are transformed from a fibrous-like structure to a smaller-sized block arrangement (with sizes of 10 - 1000 nm and shapes including squares, needles, spheres, etc.), increasing the coverage rate, smoothness and orderliness of SAM on the substrate.

[0034] (2) Enhancing the cell performance: Significantly improving the photoelectric conversion efficiency of the perovskite solar cell (the highest PCE reaches 26.58%), while improving the open-circuit voltage (VOC), short-circuit current (JSC) and fill factor (FF), and reducing interface recombination and leakage current.

[0035] (3) Strong process compatibility: This method has a simple process and is completely compatible with the existing solution preparation process, suitable for the large-scale production of large-area perovskite solar cells, providing technical support for industrialization. Brief Description of the Drawings

[0036] Figure 1 It is a flowchart of the method for preparing a perovskite solar cell based on interface modification according to the present invention;

[0037] Figure 2 It is a flowchart of the method for regulating the monodispersity of self-assembled monolayers by CF3-PhACl in the method for preparing a perovskite solar cell based on interface modification according to the present invention;

[0038] Figure 3 It is a graph of the conversion efficiency of the corresponding perovskite cells when the additives in the SAM solution are MeO-PEAI (Example 2), OH-PEAI (Example 2), CF3-PEAI (Example 2) and MeO-PhAI (Example 2) in the method for preparing a perovskite solar cell based on interface modification according to the present invention;

[0039] Figure 4 This is a graph showing the corresponding perovskite cell conversion efficiency when the concentrations of CF3-PhACl in the hole transport layer precursor solution are 0.5 mg / mL, 1.0 mg / mL, 1.5 mg / mL, 2.0 mg / mL, and 2.5 mg / mL, respectively, in the preparation method of perovskite solar cells based on interface modification described in the present invention (Example 1).

[0040] Figure 5 The hole transport layer prepared under the optimal conditions in the preparation method of the interface-modified perovskite solar cell described in the present invention (Example 3) 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 statistical comparison graphs of their open circuit voltage (VOC), short circuit current (JSC), fill factor (FF) and power conversion efficiency (PCE) are obtained.

[0041] Figure 6 The optimal efficiency of the cell obtained under the optimal conditions for preparing the hole transport layer in the method for preparing a perovskite solar cell based on interface modification of the present invention (Example 3) and the hole transport layer prepared by the traditional spin coating method (Comparative Example 1) is JV Curve comparison. DETAILED DESCRIPTION

[0042] 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.

[0043] like Figure 1 As shown, this scheme provides a method for preparing a perovskite solar cell based on interface modification, including 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:

[0044] Step (1) Cleaning the transparent conductive layer: This step is used to remove contaminants (such as organic matter, dust, metal ions, etc.) on the surface of the transparent conductive layer, improve the surface flatness and cleanliness, ensure the close bonding between the subsequent functional layer (such as the hole transport layer) and the substrate, and avoid the increase of contact resistance or the generation of defects due to interface impurities;

[0045] Step (2) A hole transport layer is prepared on the transparent conductive layer using a self-assembling molecular material and a dipole molecule additive. 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 dipole molecule additive is 0.5 mg / mL-2.5 mg / mL; the self-assembling molecular material is a phosphate-based molecule, and the dipole molecule additive is 4-trifluoromethylphenylammonium chloride (CF3-PhACl), 4-methoxyphenylethylammonium iodide (MeO-PEAI), 4-hydroxyphenylethylammonium iodide (OH-PEAI), 3-trifluoromethylphenylethylammonium iodide (CF3-PEAI), 4-methoxyphenylammonium iodide At least one of (MeO-PhAI), 4-trifluoromethyl-benzylammonium chloride, 4-(trifluoromethyl)phenethyl bromide, 2-(trifluoromethyl)phenethyl bromide, 1-(2-bromoethyl)-3-(trifluoromethyl)benzene, 1-(3-trifluoromethylphenyl)ethyl bromide, p-trifluoromethylbenzonitrile, 4-chlorophenethylammonium chloride, 3-methoxyphenethylammonium iodide, 2-methoxyphenethylammonium iodide, 4-methoxy-phenylammonium iodide, and 4-fluorobenzylammonium iodide; wherein the self-assembled molecular material (SAM) is used to form an ordered monolayer as a channel for hole transport, while regulating the surface energy of the substrate and improving the crystallization quality of the perovskite light-absorbing layer; the dipole molecule additive destroys the SAM through dipole-dipole interaction. The fibrous aggregate structure of micelles transforms them into smaller block-like arrangements, thereby improving the coverage, uniformity, and density of the SAM layer, reducing interface defects, and enhancing hole transport efficiency. This layer, through the synergistic effect of self-assembled molecular materials (SAM) and dipole molecule additives, effectively solves the problems of traditional SAM agglomeration and loose structure, providing key technical support for the preparation of high-performance perovskite cells.

[0046] Step (3) preparing a perovskite light-absorbing layer on the hole transport layer; this layer serves as the core light-absorbing layer of the solar cell and generates electron-hole pairs by absorbing photons;

[0047] Step (4) preparing a passivation layer on the perovskite light absorbing layer; the passivation layer passivates the uncoordinated ions (such as Pb² + ) and lattice defects, reducing the recombination loss of carriers (electrons / holes) at the interface, while improving the environmental stability of the perovskite film (such as resistance to humidity and oxygen corrosion); the passivation layer in this embodiment is 1,3-propylenediamine iodide (PDAI2);

[0048] Step (5) An electron transport layer is prepared on the passivation layer; this layer selectively transports electrons generated by the perovskite layer and blocks holes to achieve charge separation. At the same time, as a transmission channel for electrons from the perovskite layer to the electrode, its energy level matching (such as the lowest unoccupied molecular orbital energy level of C60) directly affects the electron extraction efficiency; the electron transport layer in this embodiment is fullerene (C 60 ) or [6,6]-phenyl-C 61 / C 71- isomethyl butyrate (PCBM);

[0049] Step (6) preparing an interface buffer layer on the electron transport layer; this layer is used to adjust the energy level matching between the electron transport layer and the electrode, reduce the electron transport barrier, and also serves as a protective layer to prevent the electrode material (such as Ag, Cu) from diffusing into the battery, thereby improving the stability of the device; in this embodiment, the interface buffer layer is 2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline (BCP) or tin dioxide (SnO2);

[0050] Step (7) An electrode layer is prepared on the interface buffer layer. This layer serves as the current extraction terminal of the battery, collecting electrons conducted by the electron transport layer to form a complete external circuit path. The electrode material is required to have high conductivity (such as Cu, Ag, Au) and good stability to ensure the current output capacity of the device during long-term operation. The electrode layer is made of copper, silver, or gold.

[0051] It should be noted that the types of perovskite solar cells in this scheme include single-cell perovskite solar cells, as well as the hole collection layer of the broadband perovskite part in the perovskite / crystalline silicon tandem solar cell; and also include perovskite / perovskite tandem solar cells, which serve as the hole transport layer of wide bandgap and narrow bandgap cells respectively.

[0052] The methods for preparing 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 and atomic layer deposition.

[0053] The 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.

[0054] Wherein, 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.

[0055] Step (2) of the present method is specifically as follows: mixing the self-assembling molecular material and the dipole molecule additive in an ethanol 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 3000rpm-7000rpm, the acceleration is 4000rpm / s-8000rpm / s, and the spin coating time is 10s-30s; in addition, the annealing temperature is 80℃-120℃, 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.

[0056] Wherein, the self-assembling molecular materials include [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 A series of phosphate molecules, including [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), and [4-(3,7-dibromo-10H-phenoxazin-10-yl)butyl]phosphate (2Br-4PAPXZ).

[0057] As an optimization of this embodiment, the concentration of the self-assembling molecular material in the ethanol solvent is 0.75 mg / mL, and the concentration of the dipole molecule additive in the ethanol solvent is 1.5 mg / mL;

[0058] The self-assembling molecular material is [2-(3,6-dimethoxy-9H-carbazole-9-yl)ethyl]phosphoric acid (MeO-2PACz);

[0059] The dipole molecule additive is 4-trifluoromethylphenylammonium chloride (CF3-PhACl).

[0060] It should be noted that the self-assembled molecular material in this embodiment forms SAM micelles in solution. The size of the SAM micelles is 10-1000 nm, and the shapes include square, needle, sphere, island, network, layer, dendrite, rod and amorphous.

[0061] Specifically, SAM micelles are closely related to step S2, "Preparing a hole transport layer comprising a self-assembled molecular material and a dipole molecule additive on the transparent conductive layer." During the preparation of the hole transport layer, SAM micelles are a form of the self-assembled molecular material in solution. The self-assembled molecular material forms SAM micelles in solution, and their morphology, size, and structure, among other properties, significantly influence the preparation and performance of the hole transport layer.

[0062] SAM micelle agglomeration affects the optimal contact between the perovskite and hole transport layer (HTTL) interfaces and the crystallization quality of the perovskite film. In this protocol, by introducing a dipolar molecule additive, such as 4-trifluoromethylphenylammonium chloride, in step S2, the SAM micelles in the solution transform from a fibrous structure to a smaller, blocky arrangement, thereby improving the quality of the HTL film and enhancing hole transport efficiency.

[0063] The general structural formula of the material of the perovskite light absorbing layer in step (3) of this method is ABX3;

[0064] 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:

[0065] B is selected from Pb 2+ 、Ge 2+ 、Sn 2+ Any one or a combination of at least two of the following:

[0066] X is selected from Cl - Br - or I - Any one or a combination of at least two of .

[0067] The materials of the perovskite light absorbing layer 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), bandgap range is 1.49-1.75eV, thickness range is 400nm-1000nm.

[0068] The material of the perovskite light absorbing layer may include wide bandgap perovskite with a bandgap width ranging from 1.60 to 1.8 eV, including Cs x MA y FAz PbI 3-n Br n (x + y + z = 1, 0 < n < 3), with a thickness range of 200 nm - 1000 nm;

[0069] The material of the perovskite light - absorbing layer may also include narrow - bandgap perovskite, with a bandgap width range of 1.20 - 1.50 eV, including C sx MA y FA z SnPb n I3 (x + y + z = 1, 0 < n < 3), with a thickness range of 500 nm - 2000 nm.

[0070] It should be noted that the perovskite solar cells applying the SAM layer prepared by this method not only include the single - junction cells of the above - mentioned various different perovskites, but also include 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.

[0071] 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.

[0072] The perovskite solar cells applying 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. Example 1

[0073] This example provides a preparation method of a perovskite solar cell based on interface modification, as follows:

[0074] Step (1): Clean the transparent conductive layer

[0075] Operation details: Ultrasonic clean the ITO or FTO substrate glass in the order of acetone → IPA → acetone → IPA, with each cleaning for 20 minutes; after cleaning, dry at 65 °C and then perform ultraviolet ozone treatment for 15 minutes to obtain a clean transparent conductive layer substrate.

[0076] Step (2): Prepare the hole - transport layer (including SAM material and CF3 - PhACl dipole molecule additive)

[0077] Material preparation: The self-assembled molecular material MeO-2PACz (concentration 0.75 mg / mL) and the dipole molecular additive CF3-PhACl (concentrations of 0.5 mg / mL, 1.0 mg / mL, 1.5 mg / mL, 2.0 mg / mL, and 2.5 mg / mL, respectively) were dissolved in ethanol solvent to prepare a hole transport layer precursor solution.

[0078] Film formation process: Take 65 μL of precursor solution, spin coat at 5000 rpm for 20 seconds, and then anneal at 100°C for 10 minutes (annealing environment is air).

[0079] Step (3): Preparation of perovskite light-absorbing layer

[0080] Material composition: The chemical formula of perovskite material is Cs 0.05 MA 0.05 FA 0.90 PbBr 0.1 I 2.9 A 1.4 M precursor solution was prepared by CsI, FAI, MABr, MACl, PbBr2 and PbI2 in a DMF:DMSO mixed solvent (volume ratio 4:1).

[0081] Additive modification: 10 mol% MACl, 1 mg / mL GuaBCI, 1 mg / mL PMACI, and 2 mg / mL PbCl2 were added to the precursor solution and stirred for more than 6 hours.

[0082] Film formation process: Take 65 μL of solution and drop it on the hole transport layer. First, spin-coat it at 1000 rpm for 5 seconds, then spin-coat it at 5000 rpm for 30 seconds. Finally, add 120 μL of chlorobenzene as an antisolvent within 15 seconds. After spin coating, anneal it at 110°C for 20 minutes to form a light-absorbing layer with a thickness of about 400-1000 nm.

[0083] Step (4): Preparation of passivation layer

[0084] Materials and solutions: The passivation layer material was 1,3-propylenediamine iodide (PDAI2), dissolved in a mixed solvent of IPA and DMSO (IPA:DMSO = 99:1 v:v) at a concentration of 1 mg / mL.

[0085] Film forming process: The passivation solution was spin-coated at 5000 rpm for 20 seconds and annealed at 110°C for 10 minutes to form a defect passivation layer.

[0086] Step (5) S5: Preparation of electron transport layer

[0087] Materials and process: The film was transferred to a thermal evaporator and heated in a high vacuum environment (<5×10-5 Pa) by thermal evaporation to deposit 18 nm thick fullerene (C 60 ), acts as an electron transport medium to selectively extract electrons generated in the perovskite layer.

[0088] Step (6): Preparation of interface buffer layer

[0089] Materials and processes: Continue to deposit 20 nm thick SnO2 under high vacuum as a buffer layer between the electron transport layer and the electrode to optimize energy level matching and prevent electrode material diffusion.

[0090] Step (7): Preparation of electrode layer

[0091] Materials and Process: In a high vacuum environment, 80 nm thick copper (Cu) is deposited by thermal evaporation as the electrode layer to form a complete current collection path. Example 2

[0092] This embodiment provides a perovskite solar cell, which differs from the above-mentioned embodiment 1 only in that the dipole molecule additives in the SAM solution are MeO-PEAI, OH-PEAI, CF3-PEAI and MeO-PhAI, with a concentration of 1.5 mg / mL. The other materials, structures and preparation methods are the same as those in embodiment 1. Example 3

[0093] This embodiment provides a perovskite solar cell, which differs from the above-mentioned embodiment 1 only in that the concentration of CF3-PhACl in the hole transport layer precursor solution is only 1.5 mg / mL, and the other materials, structures and preparation methods are the same as those in embodiment 1.

[0094] Comparative Example 1

[0095] This embodiment provides a perovskite solar cell, which differs from the above-mentioned embodiment 2 only in that the hole transport layer precursor solution contains only MeO-2PACz with 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 embodiment 2.

[0096] Performance Testing

[0097] like Figure 2 As shown, the SAM micelles of Comparative Example 1 exhibited a fiber-like structure with larger gaps when spin-coated into a film. After the introduction of CF3-PhACl in Example 3, the micelle morphology changed to a smaller block structure with smaller gaps and better uniformity when spin-coated into a film.

[0098] In this scheme, all photovoltaic parameters of the single-junction perovskite solar cell with SAM layer controlled by CF3-PhACl have been significantly improved, including V OC 、J SC , FF, and PCE. At a concentration of 1.5 mg / mL, the perovskite solar cell exhibited a power conversion efficiency of 26.58%, indicating that the use of the above additives created an excellent interface contact at the HTL / perovskite buried interface, which is beneficial to the transport of photogenerated holes.

[0099] like Figure 4 As shown in the figure, the effect of CF3-PhACl concentration (0.5 mg / mL-2.5 mg / mL) on the conversion efficiency of perovskite cells. When the CF3-PhACl concentration is 1.5 mg / mL, the battery power conversion efficiency (PCE) reaches a peak of 26.58%, indicating that there is an optimal additive concentration range.

[0100] like Figure 5 As shown, by comparing the photovoltaic parameters of Example 3 (optimal conditions) with those of Comparative Example 1 (traditional spin coating method), it can be seen that: V OC 、J SC , FF and PCE are significantly higher than those of Comparative Example 1, among which PCE is increased by about 2.05%, proving the effectiveness of interface modification.

[0101] like Figure 3 Figure 2 shows the effects of different dipole molecule additives (MeO-PEAI, OH-PEAI, CF3-PEAI, and MeO-PhAI) on the conversion efficiency of perovskite cells. The data demonstrates that all additives improve cell efficiency, with CF3-PhACl providing a more significant improvement, demonstrating the universality and effectiveness of dipole molecule additives.

[0102] like Figure 6 As shown, by Example 3 and Comparative Example 1 JV Curve comparison shows that the JV curve of Example 3 performs better in the full voltage range, and both the short-circuit current and the open-circuit voltage are significantly improved, further verifying the improvement of battery performance by interface modification.

[0103] At the same time, this method was used to prepare a denser and more uniform SAM layer, which greatly reduced the leakage current of the buried interface of the perovskite cell and significantly reduced the interface recombination, thereby significantly improving the conversion efficiency of the solar cell.

[0104] 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 interface modification, 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) A hole transport layer is prepared on the transparent conductive layer using a self-assembling molecular material and a dipole molecule additive. 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 dipole molecule additive is 0.5 mg / mL-2.5 mg / mL; the self-assembling molecular material is a phosphate-based molecule, and the dipole molecule additive is 4-trifluoromethylphenylammonium chloride (CF3-PhACl), 4-methoxyphenethylammonium iodide (MeO-PEAI), 4-hydroxyphenethylammonium iodide ammonium (OH-PEAI), 3-trifluoromethylphenethylammonium iodide (CF3-PEAI), 4-methoxyphenylammonium iodide (MeO-PhAI), 4-trifluoromethyl-benzylammonium chloride, 4-(trifluoromethyl)phenethyl bromide, 2-(trifluoromethyl)phenethyl bromide, 1-(2-bromoethyl)-3-(trifluoromethyl)benzene, 1-(3-trifluoromethylphenyl)ethyl bromide, p-trifluoromethylbenzonitrile, 4-chlorophenethylammonium chloride, 3-methoxyphenethylammonium iodide, 2-methoxyphenethylammonium iodide, 4-methoxy-phenylammonium iodide, 4-fluorobenzylammonium iodide; 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 interface modification according to claim 1, characterized in that: The step (2) is specifically as follows: mixing the self-assembling molecular material and the dipole molecule additive in an ethanol 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 3000rpm-7000rpm, the acceleration is 4000rpm / s-8000rpm / s, and the spin coating time is 10s-30s; in addition, the annealing temperature is 80℃-120℃, the annealing time is 5min-15min, and the annealing environment is in an air environment or in a glove box protected by inert gas.

3. The method for preparing a perovskite solar cell based on interface modification according to claim 2, characterized in that: The self-assembling molecular materials in step (2) include [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-carbazol-9-yl)propyl]phosphate (Me-3PACz), [6-(3,6-dimethyl-9H-carbazol-9-yl)hexyl]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)oct ...1-(3,6-dimethyl-9H-carbazol-9-yl) [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 (6PACz), [8-(9H-carbazol-9-yl)octyl]phosphate (8PACz), ... ), [4-(N,N-bis(4-methoxyphenylamino)phenyl)propyl]phosphoric acid (MeO-TPA-3PA), 2,3,4,5,6-pentafluorobenzylphosphoric acid (F5BPA), [2-(9H-9'-phenyl-3,3'-biscarbazol-9-yl)ethyl]phosphoric acid (2PABCz), [4-(9H-9'-phenyl-3,3'-biscarbazol-9-yl)butyl]phosphoric acid (4PABCz), [4-(diphenylamino)phenethyl]phosphoric acid (TPA-2PA), [4-(Diphenylamino)phenylpropyl]phosphate (TPA-3PA), [4-(10H-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-(3,6-di-tert-butyl-9H-carbazol-9-yl)methyl]phosphate (tBu-1PACz), [2-(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-(3,6-di-tert-butyl-9H-carbazol-9-yl)methyl]phosphate (tBu-1PACz), [2-(3,6-dibromo-9H-carbazol-9-yl)[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 interface modification according to claim 3, characterized in that: The concentration of the self-assembling molecular material in the ethanol solvent is 0.75 mg / mL, and the concentration of the dipole molecule additive in the ethanol solvent is 1.5 mg / mL; The self-assembling molecular material is [2-(3,6-dimethoxy-9H-carbazole-9-yl)ethyl]phosphoric acid (MeO-2PACz); The dipole molecule additive is 4-trifluoromethylphenylammonium chloride (CF3-PhACl).

5. The method for preparing a perovskite solar cell based on interface modification according to claim 3 or 4, characterized in that: The self-assembling molecular material forms SAM micelles in a solution. The size of the SAM micelles is 10-1000 nm, and the shapes include square, needle, sphere, island, network, layer, dendrite, rod and amorphous.

6. The method for preparing a perovskite solar cell based on interface modification according to claim 1, characterized in that: The step (1) specifically comprises: 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.

7. The method for preparing a perovskite solar cell based on interface modification according to claim 6, characterized in that: 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.

8. The method for preparing a perovskite solar cell based on interface modification 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 .

9. The method for preparing a perovskite solar cell based on interface modification according to claim 8, characterized in that: The material of the perovskite light absorbing layer includes MAPbI3, FAPbI3, MA x FA (1-x) PbI3, Cs x MA y FA z PbI3, the band gap range is 1.49-1.75eV, and the thickness range is 400nm-1000nm.

10. The method for preparing a perovskite solar cell based on interface modification according to claim 8, characterized in that: The material of the perovskite light absorbing layer includes wide bandgap perovskite with a bandgap width ranging from 1.60 to 1.8 eV, including Cs x MA y FA z PbI 3-n Br n , with a thickness ranging from 200nm to 1000nm; or, the material of the perovskite light absorbing layer includes narrow bandgap perovskite with a bandgap width ranging from 1.20 to 1.50eV, including C sx MA y FA z SnPb n I3, thickness range is 500nm-2000nm.

Images