Method for manufacturing perovskite cell and perovskite cell

Abstract

The application relates to a preparation method of a perovskite battery. The method comprises the following steps: preparing a perovskite precursor solution, wherein the solute of the perovskite precursor solution comprises a material with a molecular formula of ABX3 and a self-assembled monolayer material, A is an organic cation, B is a metal cation, and X is a halide anion; coating the perovskite precursor solution on a conductive substrate to form a perovskite precursor layer; and performing heat annealing treatment on the perovskite precursor layer to crystallize the perovskite precursor layer, so that a first transport layer, a P-type perovskite layer and an N-type perovskite layer are sequentially stacked in a direction away from the conductive substrate. The preparation method of the perovskite battery can effectively improve the power transmission efficiency of the prepared perovskite battery.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of new energy conversion and new energy battery components, in particular to a preparation method of a perovskite battery and the perovskite battery. BACKGROUND

[0002] Metal halide perovskite has become one of the most promising thin-film solar cell materials due to its excellent photoelectric properties such as excellent visible light absorption ability and long carrier diffusion length. The hole transport layer (HTL) in the structure mainly functions to block electrons, enhance hole transport and prevent quenching caused by direct contact between the perovskite active layer and the electrode.

[0003] However, the commonly used material for the hole transport layer is a polymer such as PTAA, which has disadvantages such as poor coverage, high price and poor stability, thereby resulting in poor power transmission efficiency of the perovskite battery. SUMMARY

[0004] Therefore, it is necessary to provide a preparation method of a perovskite battery in view of the problem of power transmission efficiency of the perovskite battery.

[0005] The preparation method of the perovskite battery comprises the following steps.

[0006] A perovskite precursor solution is prepared, and the solute of the perovskite precursor solution comprises a material with a molecular formula of ABX3 and a self-assembled monolayer material, wherein A is an organic cation, B is a metal cation, and X is a halide anion.

[0007] The perovskite precursor solution is coated on a conductive substrate to form a perovskite precursor layer.

[0008] The perovskite precursor layer is subjected to thermal annealing treatment to crystallize the perovskite precursor layer, thereby forming a first transport layer, a P-type perovskite layer and an N-type perovskite layer which are stacked in sequence in a direction away from the conductive substrate.

[0009] Optionally, the self-assembled monolayer material comprises a hydrophilic group, and during the thermal annealing treatment of the perovskite precursor layer, the hydrophilic group moves towards the conductive substrate, and part of the self-assembled monolayer material moves to the bottom of the perovskite precursor layer to crystallize to form the first transport layer in contact with the conductive substrate.

[0010] Optionally, the hydrophilic group comprises a phosphoric acid group, and during the crystallization of the perovskite material, the phosphoric acid group moves towards the conductive substrate, the content of the phosphoric acid group on the side of the perovskite precursor layer close to the conductive substrate is greater than the content of the phosphoric acid group on the side away from the conductive substrate, and the perovskite material crystallizes on the first transport layer to form the P-type perovskite layer and the N-type perovskite layer which are stacked.

[0011] Optionally, the content of phosphonic groups gradually decreases from the top surface of the N-type perovskite layer to the bottom surface of the P-type perovskite layer.

[0012] Optionally, the P-type perovskite layer comprises a plurality of sub-P-type layers formed in sequence on the first transport layer, and the content of holes in the plurality of sub-P-type layers gradually increases layer by layer in a direction away from the conductive substrate.

[0013] The N-type perovskite layer comprises a plurality of sub-N-type layers formed in sequence on the P-type perovskite layer, and the content of electrons in the plurality of sub-N-type layers gradually increases layer by layer in a direction away from the conductive substrate.

[0014] Optionally, the self-assembled monolayer material further comprises a hydrophobic group, and during the process of thermally annealing the perovskite precursor layer, the hydrophobic group moves in a direction away from the conductive substrate, and part of the self-assembled monolayer material moves to the top of the perovskite precursor layer to form a passivation layer on the top surface of the N-type perovskite layer.

[0015] Optionally, the perovskite precursor solution is prepared by:

[0016] providing iodine halide, inorganic metal halide, organic ammonium salt, and the self-assembled monolayer material;

[0017] dissolving the iodine halide, the inorganic metal halide, the organic ammonium salt, and the self-assembled monolayer material in an organic solvent according to a predetermined proportion to obtain the perovskite precursor solution;

[0018] Optionally, the self-assembled monolayer material comprises one or more of 4PADCB, BCB-C4PA, BCBBr-C4PA, and DMACPA.

[0019] Optionally, the concentration of the self-assembled monolayer material in the perovskite precursor solution is 0.1 mg / mL to 10 mg / mL.

[0020] A perovskite solar cell, characterized by being prepared by any one of the preparation methods of the perovskite solar cell.

[0021] A photovoltaic module, characterized by comprising the perovskite solar cell prepared by any one of the preparation methods of the perovskite solar cell.

[0022] The preparation method of the perovskite battery provided in the above embodiment is as follows: a perovskite precursor solution is prepared, the solute of the perovskite precursor solution includes a material with a molecular formula of ABX3 and a self-assembled monolayer material, wherein A is an organic cation, B is a metal cation, and X is a halide anion; the perovskite precursor solution is coated on a conductive substrate to form a perovskite precursor layer; and the perovskite precursor layer is subjected to heat annealing treatment to crystallize the perovskite precursor layer, so as to form a first transport layer, a P-type perovskite layer and an N-type perovskite layer which are sequentially stacked in a direction away from the conductive substrate. Since the self-assembled monolayer film (SAMs) has many advantages such as low material consumption, compatibility with flexible substrates, adjustable band gap, high light transmittance and green environmental protection, the perovskite precursor solution obtained by combining the self-assembled monolayer film material and the perovskite preparation solution can make the SAMs molecules disperse to the grain boundaries and the bottom of the film surface from the precursor solution when the perovskite layer is prepared, so as to form an obvious HTL and form an energy level gradient, and a small amount of SAMs diffuses to the top surface of the perovskite film to passivate the defects at the surface and the grain boundaries. The coordination complex between the deprotonated phosphoric acid group of the SAMs molecules and the lead polyiodide of the perovskite is responsible for mechanical absorption and electronic charge transfer, which leads to p-type doping of the perovskite film. Therefore, the morphology of the prepared perovskite layer is uniform, the charge transport capacity is enhanced, non-radiative recombination is inhibited, and the power conversion efficiency of the perovskite battery is effectively improved. BRIEF DESCRIPTION OF DRAWINGS

[0023] Figure 1 A flowchart of a preparation method of a perovskite battery according to an embodiment of the present application is shown in the figure;

[0024] Figure 2 An example diagram of a perovskite layer of a perovskite battery according to an embodiment of the present application is shown in the figure;

[0025] Figure 3 A correlation distribution diagram of radiation wavelength and radiation intensity in a current transmission process of a perovskite layer after annealing according to an embodiment of the present application is shown in the figure;

[0026] Figure 4 A layered diagram of a perovskite layer prepared according to an embodiment of the present application is shown in the figure;

[0027] Figure 5 A correlation distribution diagram of time and electromagnetic wavelength in a current transmission process of a perovskite layer after annealing according to an embodiment of the present application is shown in the figure;

[0028] Figure 6 Structural formulas of other materials in a self-assembled monolayer material according to an embodiment of the present application are shown in the figure. DETAILED DESCRIPTION

[0029] In order to make the above objectives, characteristics and advantages of the present application more apparent, more comprehensible, the specific embodiments of the present application will be described in detail below with reference to the drawings. In the following description, a large number of specific details are set forth in order to provide a thorough understanding of the present application. However, the present application can be practiced in a large number of other ways than those described herein, and one of ordinary skill in the art can make similar modifications without departing from the spirit of the present application, and therefore the present application is not limited to the specific implementations disclosed below.

[0030] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. In the description of the application, it should be understood that the terms "first", "second", etc. are used only for descriptive purposes and are not to be construed as indicating or implying relative importance or an indicated number of technical features. Therefore, the features defined with "first", "second" can explicitly or implicitly include at least one of the features. In the description of the application, the meaning of "a plurality of" is at least two, for example, two, three, etc., unless otherwise specifically limited.

[0031] The terms used in the specification of the present application are only for the purpose of describing the specific embodiments of the present application, and are not intended to limit the present application. It should be understood that when an element is considered to be "connected" to another element, it can be directly connected to the other element or there can be an intermediate element. In contrast, when an element is referred to as being "directly" connected to another element, there is no intermediate element.

[0032] Please refer to Figure 1 The present application provides a preparation method of a perovskite battery. The method comprises:

[0033] Step S101, preparing a perovskite precursor solution.

[0034] The solute of the perovskite precursor solution comprises a material with a molecular formula of ABX3 and a self-assembled monolayer material, wherein A is an organic cation, B is a metal cation, and X is a halide anion.

[0035] In the preparation of the perovskite precursor solution, the solution amount requirement value of the perovskite precursor solution is obtained, and based on the solution amount requirement value, the material configuration amount of the ABX3 material in the perovskite precursor solution corresponding to the solution amount requirement value is calculated through the preparation algorithm of the perovskite precursor solution. Based on the material configuration amount, the perovskite precursor solution of the traditional ABX3 material is prepared. Then, based on the solution capacity of the perovskite precursor solution of the traditional ABX3 material, the material configuration amount of the self-assembled monolayer material and the solution amount of the self-assembled monolayer material are determined according to the preset concentration value range of the self-assembled monolayer material in the perovskite precursor solution. Based on the material configuration amount and the solution amount of the self-assembled monolayer material, the material solution of the self-assembled monolayer material is configured, and finally the material solution of the self-assembled monolayer material is added to the perovskite precursor solution of the traditional ABX3 material and mixed and stirred to complete the preparation process of the perovskite precursor solution. The preset concentration value range of the self-assembled monolayer material in the perovskite precursor solution can be 0.01-0.5mg / ml.

[0036] Then, the material solution of the self-assembled monolayer material is poured into the perovskite precursor solution of the traditional ABX3 material, and stirred uniformly at a constant speed for 3-5 minutes in a clockwise direction, thereby completing the configuration step of the perovskite precursor solution. The ABX3 material includes one or more of CsI, FAI(CH5IN2), MAI(CH6IN), MABr(CH6BrN), MACl(CH6ClN), PbI2 and PbBr2. The self-assembled monolayer material is used to divide the perovskite layer into sub-perovskite layers corresponding to different energy levels. The concentration value range is 0.1-10mg / mL.

[0037] In step S102, the perovskite precursor solution is coated on the conductive substrate to form a perovskite precursor layer.

[0038] The conductive substrate is coated by a one-step spin coating film process on the conductive substrate, which can be but is not limited to a conductive glass ITO (Indium Tin Oxide) substrate or a fluorine-doped tin oxide FTO (Fluorine-doped Tin Oxide) substrate.

[0039] In step S103, the perovskite precursor layer is heat annealed to crystallize the perovskite precursor layer, forming a first transport layer, a P-type perovskite layer and an N-type perovskite layer stacked in turn in a direction away from the conductive substrate.

[0040] The first transport layer is a compact HTL layer formed by the material of the self-assembled monolayer material deposited on the surface of the conductive substrate after annealing. Figure 2As shown, an example diagram of a perovskite layer for preparing a perovskite cell. Wherein, the conductive substrate is an ITO glass substrate.

[0041] In some embodiments, the heat annealing treatment of the perovskite precursor layer comprises: heat annealing at a temperature of 80-150℃ for 1-60min.

[0042] In other embodiments, the heat annealing treatment of the perovskite precursor layer comprises: a first heat annealing treatment, heat annealing at a temperature of 50-100℃ for 1-60min. A second heat annealing treatment, heat annealing at a temperature of 90-150℃ for 1-60min.

[0043] Wherein, as shown, the distribution diagram of the radiation wavelength and the radiation intensity in the current transmission process of the hole-free (left) perovskite layer doped with 4PADCB and the hole-containing (right) perovskite layer after annealing, respectively, wherein the PL peak intensity of the hole-free perovskite layer doped with 4PADCB is improved, the non-radiative recombination at the interface is inhibited, and the defects are reduced. Figure 3

[0044] Based on the above scheme, by adding the self-assembled monolayer material into the perovskite precursor layer solution in a certain proportion, and then heat annealing to prepare the perovskite layer, the morphology of the prepared perovskite layer is uniform, not only the charge transport capacity is enhanced, the non-radiative recombination is inhibited, but also the power transmission efficiency of the perovskite cell is effectively improved.

[0045] Optionally, the self-assembled monolayer material includes a hydrophilic group, and during the heat annealing treatment of the perovskite precursor layer, the hydrophilic group moves towards the direction close to the conductive substrate, part of the self-assembled monolayer material moves to the bottom of the perovskite precursor layer, and crystallizes to form a first transport layer in contact with the conductive substrate.

[0046] Wherein, after heat annealing treatment, the carrier concentration of the material solution in the N-type sub-perovskite layer located above the P-type sub-perovskite layer is in the range of 10 15 ~ 10 18 cm 3 -1, and the carrier concentration of the material solution in the obtained P-type sub-perovskite layer is in the range of 10 10 ~ 10 8 cm 3 -1.

[0047] Wherein, as shown, Figure 4 ​As shown, the perovskite layer obtained after preparation is from top to bottom, in turn, the top surface passivation layer with a concentration of a first concentration value, the first N-type sub-perovskite layer with a concentration of a second concentration value, the second N-type sub-perovskite layer with a concentration of a third concentration value, the first P-type sub-perovskite layer with a concentration of a fourth concentration value, the second P-type sub-perovskite layer with a concentration of a fifth concentration value, and the HTL layer formed by depositing SAMS material on the conductive substrate and annealing. Among them, the concentration of each layer of the perovskite layer is not clear, but gradually decreases, and the concentration is gradually reduced. Among them, the carrier concentration range corresponding to the first concentration value can be 10 20 cm 3 -1 18 , the carrier concentration range corresponding to the second concentration value can be 10 3 cm 15 -1 3 , the carrier concentration range corresponding to the third concentration value can be 10 10 cm 3 -1 8 , the carrier concentration range corresponding to the fourth concentration value can be 10 3 cm 2 -1 3 . Among them, when constructing a perovskite battery including the perovskite layer, a transparent electrode layer and a buffer layer need to be added above the perovskite layer.

[0048] As Figure 5 shown, respectively, the hole-doped 4PADCB perovskite layer (left) and the hole-free perovskite layer (right) after annealing, the distribution diagram between time and electromagnetic wavelength in the current transmission process of the two perovskite layers, wherein the carrier lifetime of the sample of the hole-free perovskite layer doped with 4PADCB decreases more slowly, indicating that the defects are inhibited, and the sample with holes is on the contrary, indicating that the perovskite carrier transmission capacity of the hole-free perovskite layer doped with 4PADCB is enhanced.

[0049] Based on the above method, it can be ensured that after heat annealing treatment, layers with different concentration gradient are formed, and it can be ensured that the prepared P-type perovskite layer and N-type perovskite layer can have a specific concentration gradient. The concentration difference between the two adjacent layers can be 10 2 cm 3 -1 .

[0050] Optionally, the hydrophilic group includes a phosphate group, and during the crystallization of the perovskite material, the phosphate group moves towards the conductive substrate, and the content of the phosphate group on the side of the perovskite precursor layer close to the conductive substrate is greater than the content of the phosphate group on the side away from the conductive substrate. The perovskite material crystallizes on the first transport layer to form a stacked P-type perovskite layer and N-type perovskite layer.

[0051] Optionally, the content of the phosphoric acid group gradually decreases from the top surface of the N-type perovskite layer to the bottom surface of the P-type perovskite layer.

[0052] The content of the phosphoric acid group gradually decreases, so that the P-type perovskite layer can be isolated from the N-type perovskite layer to ensure the constant structural positional relationship of the P-type perovskite layer and the N-type perovskite layer and the material stability in different perovskite layers, so that the energy level gradient difference of the perovskite layer is reduced, thereby being more matched, which can effectively improve the carrier transport capacity and reduce the defect density of the interface and the perovskite thin film, and inhibit the non-radiative recombination of interface carriers.

[0053] Optionally, the P-type perovskite layer includes a plurality of sub-P-type layers formed in the first transport layer in sequence, and the content of holes in the plurality of sub-P-type layers increases layer by layer in a direction away from the conductive substrate; and the N-type perovskite layer includes a plurality of sub-N-type layers formed in the P-type perovskite layer in sequence, and the content of electrons in the plurality of sub-N-type layers increases layer by layer in a direction away from the conductive substrate.

[0054] Specifically, the surface work function of the original perovskite deposited ITO or FTO is moved upward, and the surface work function of the perovskite (SAMs) is moved downward, and the perovskite (SAMs) energy band shows upward bending, which enables the hole extraction at the interface. Electrons accumulate around the hydrogen protons from the doped SAMs, and the electrons are transferred from the perovskite to the bottom of the perovskite (deposited SAMs part), the electron density (n) is reduced, and the electron-hole product (np) is constant when the temperature is unchanged, which increases the hole density (p), resulting in the p-type characteristics of the doped SAMs perovskite film, and the upper layer of the electron transport layer is N-type.

[0055] Based on the above scheme, the stability of the preparation of the perovskite layer can be improved by ensuring that the N-type perovskite layer is arranged first and the P-type perovskite layer is arranged later according to the concentration from high to low when the perovskite layer is generated by annealing.

[0056] Optionally, the self-assembled monolayer material further includes a hydrophobic group, and the hydrophobic group moves away from the conductive substrate during the process of heat annealing the perovskite precursor layer, and part of the self-assembled monolayer material moves to the top of the perovskite precursor layer, and a passivation layer is formed on the top surface of the N-type perovskite layer by crystallization.

[0057] Optionally, the perovskite precursor solution is prepared by: providing a halogenated iodine, an inorganic metal halide, an organic ammonium salt, and a self-assembled monolayer material; and dissolving the halogenated iodine, the inorganic metal halide, the organic ammonium salt, and the self-assembled monolayer material in an organic solvent in a predetermined proportion to obtain the perovskite precursor solution; wherein the predetermined proportion of the self-assembled monolayer material in the perovskite precursor solution obtained by dissolving the self-assembled monolayer material ranges from 0.01 mg / ml to 0.5 mg / ml, and the self-assembled monolayer material includes one or more of 4PADCB ([4-(7H-dibenzo carbazole-7-yl) butyl] phosphonic acid), BCB-C4PA ([4-(7H-benzocarbazoI-7-yl) butyl] phosphonic acid), BCBBr-C4PA ([4-(10-bromo-7H-benzocarbazoI-7-yl) butyl] phosphonic acid), and DMACPA ([2,7-dibromo-9,9-dimethylacridin-10(9H)yl) butyl] phosphonic acid). As shown in the following structural formula, the self-assembled monolayer material includes other materials. Figure 6 As shown in the following structural formula, the self-assembled monolayer material includes other materials.

[0058] Optionally, the concentration of the self-assembled monolayer material in the perovskite precursor solution ranges from 0.1 mg / ml to 10 mg / ml.

[0059] The technical features of the above-described embodiments can be combined in any manner. To make the description concise, all possible combinations of the technical features in the above-described embodiments are not described, but as long as the combinations of the technical features do not contradict each other, they should be considered within the scope of the present disclosure.

[0060] The above-described embodiments only express several implementation manners of the present application, and the description is relatively specific and detailed, but it should not be understood as a limitation on the patent scope of the present application. It should be noted that for those skilled in the art, without departing from the concept of the present application, a number of modifications and improvements can be made, which are all within the scope of the present application. Therefore, the patent protection scope of the present application should be subject to the appended claims.

Claims

1. A method of preparing a perovskite cell, characterized by, The application relates to a method for preparing a perovskite material. The method comprises the following steps: preparing a perovskite precursor solution, wherein the solute of the perovskite precursor solution comprises a material with a molecular formula of ABX3 and a self-assembled monolayer material, A is an organic cation, B is a metal cation, and X is a halide anion; coating the perovskite precursor solution on a conductive substrate to form a perovskite precursor layer; 2. The method for preparing a perovskite solar cell according to claim 1, characterized in that, heat annealing the perovskite precursor layer, so that the self-assembled monolayer material migrates directionally in a crystallization process; wherein a hydrophilic group migrates towards the conductive substrate, is enriched on the surface of the conductive substrate and forms a first transfer layer; the perovskite precursor is crystallized on the first transfer layer, and a P-type perovskite layer and an N-type perovskite layer are formed on the first transfer layer in sequence away from the conductive substrate; a hydrophobic group migrates away from the conductive substrate, and is enriched on the top surface of the N-type perovskite layer to form a passivation layer.

3. The method of claim 2, wherein the perovskite cell is prepared by the steps of: The self-assembled monolayer material comprises a hydrophilic group, and the hydrophilic group moves towards the conductive substrate in the process of heat annealing the perovskite precursor layer; part of the self-assembled monolayer material moves to the bottom of the perovskite precursor layer and is crystallized to form the first transfer layer in contact with the conductive substrate. ​ 4. The method of claim 3, wherein the perovskite cell is prepared by the steps of: The hydrophilic group comprises a phosphoric acid group, and the phosphoric acid group moves towards the conductive substrate in the crystallization process of the perovskite material; the content of the phosphoric acid group on the side of the perovskite precursor layer close to the conductive substrate is greater than that on the side away from the conductive substrate; and the perovskite material is crystallized on the first transfer layer to form the P-type perovskite layer and the N-type perovskite layer in sequence. ​ 5. The method for preparing a perovskite solar cell according to claim 4, characterized in that, The content of the phosphoric acid group gradually decreases from the top surface of the N-type perovskite layer to the bottom surface of the P-type perovskite layer. The P-type perovskite layer comprises a plurality of sub-P-type layers formed on the first transfer layer in sequence, and the content of holes in the plurality of sub-P-type layers gradually increases layer by layer away from the conductive substrate; 6. The method for preparing a perovskite solar cell according to claim 2, characterized in that, The N-type perovskite layer comprises a plurality of sub-N-type layers formed on the P-type perovskite layer in sequence, and the content of electrons in the plurality of sub-N-type layers gradually increases layer by layer away from the conductive substrate.

7. The method of claim 1-6, wherein, The self-assembled monolayer material further comprises a hydrophobic group, and the hydrophobic group moves away from the conductive substrate in the process of heat annealing the perovskite precursor layer; part of the self-assembled monolayer material moves to the top of the perovskite precursor layer and is crystallized to form the passivation layer on the top surface of the N-type perovskite layer. The method comprises the following steps: providing iodine halide, inorganic metal halide, organic ammonium salt and the self-assembled monolayer material; dissolving the iodine halide, the inorganic metal halide, the organic ammonium salt and the self-assembled monolayer material in an organic solvent according to a predetermined proportion to obtain the perovskite precursor solution; The self-assembled monolayer material comprises one or more of 4PADCB, BCB-C4PA, BCBBr-C4PA and DMACPA.

8. The method of claim 7, wherein the perovskite cell is prepared by the steps of: The concentration of the self-assembled monolayer material in the perovskite precursor solution is 0.1 mg / mL-10 mg / mL.

9. A perovskite cell, characterized in that, The preparation method of the perovskite battery according to any one of claims 1-8 is used to prepare; wherein the perovskite battery comprises a conductive substrate, and a first transport layer, a P-type perovskite layer, an N-type perovskite layer and a passivation layer which are sequentially stacked on the conductive substrate; The first transport layer, the P-type perovskite layer, the N-type perovskite layer and the passivation layer are formed by one-time coating and annealing crystallization of a perovskite precursor solution comprising a self-assembled monolayer material.

10. A photovoltaic module, characterized by, The perovskite battery prepared by the preparation method of the perovskite battery according to any one of claims 1-8.

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