Method for manufacturing perovskite layers or laminates

Abstract

To provide a perovskite layer capable of maintaining a high photoelectric conversion efficiency. 【Solution means】A compound represented by the following formula (I) AM m X n ···(I) (In formula (I), A includes any one or more of CH3NH3 + , NH2CHNH2 + and Cs + and contains any one or two or more of them, M is a metal ion containing any or both of Pb 2+ and Sn 2+ and is a metal ion containing any or both of them, X is any one or more of F - , Cl - , Br - , and I - and is any one or two or more of them, m is 0.8 to 1.2, n is 2.8 to 3.2.) And a perovskite layer containing thiocyanic acid or a salt thereof, wherein the maximum value of the total abundance of the glycine derivative, its salt and their ions exists at any position from 70% or more to 100% or less or from 0% or more to 30% or less from the surface.

Description

[Technical Field]

[0001] This invention relates to perovskite layers and solar cells. More specifically, this invention relates to perovskite layers containing Sn and Pn, in which power generation efficiency is enhanced by having a surface treatment layer containing a glycine derivative or thiocyanic acid, or an amine or a salt thereof (preferably a diamine or a salt thereof). [Background technology]

[0002] Japanese Patent Publication No. 2019-55916 describes a method for manufacturing a solar cell having a perovskite layer. The perovskite layer described in this publication contains divalent cations such as tin and lead and has an absorption region up to the long wavelength range. [Prior art documents] [Patent Documents]

[0003] [Patent Document 1] Japanese Patent Publication No. 2019-55916 [Overview of the project] [Problems that the invention aims to solve]

[0004] The objective of this invention is to provide a perovskite layer that can achieve high short-circuit current density (Jsc) and energy conversion efficiency (PCE). The object of this invention is to provide a solar cell or other device having the above-described perovskite layer. The invention described in this specification aims to solve, for example, any of the above-mentioned problems. [Means for solving the problem]

[0005] One invention described in this specification is based on the finding of an embodiment that the above problems can be solved by either including a glycine derivative, thiocyanic acid or a salt thereof in the perovskite layer, or providing a surface treatment layer containing an amine or a salt thereof (preferably a diamine or a salt thereof) on the perovskite layer.

[0006] The first invention relates to a perovskite layer. This perovskite layer is a perovskite layer containing a compound represented by formula (I) and a glycine derivative represented by formula (II) or a salt thereof. Formula (I) is AM ,

[0007] , , , ,

[0008] , , , , , X n ···(I). And in formula (I), A is any one or more of methylammonium cation (CH3NH3 + ), formamidinium cation (NH2CHNH2 + ), and cesium cation (Cs + ). M is a metal ion containing any one or both of Pb 2+ and Sn 2+ . X is any one or more of F - , Cl - , Br - , and I - . m is 0.8 to 1.2. n is 2.8 to 3.2.

[0007] And it is preferable that the maximum value of the total abundance of the glycine derivative represented by formula (II), its salt, and their ions exists at any position from 70% or more to 100% or less or from 0% or more to 30% or less from the surface of the perovskite layer.

[0008] The glycine derivative represented by formula (II) is as follows.

Chemical formula

[0009] A preferred example of any of the above perovskite layers is where M is Pb 2+ and Sn 2+ It is a metal ion that contains both.

[0010] A preferred example of the perovskite layer described above is the perovskite layer further comprising thiocyanate or a salt thereof. Thiocyanate is a thiocyanate ion (SCN - ) are contained in the perovskite layer. Thiocyanate ions (SCN) are present at 20% and 80% of the surface of the perovskite layer. - The existence values ​​of ) are each d SCN20% and d SCN80% Let's assume that. Then, d SCN80% ,d SCN20% It is more than 5 times or less than 1 / 5 of the surface during manufacturing. SCN80% ,d SCN20% This is more than five times that amount.

[0011] A preferred example of the perovskite layer described above is a perovskite layer with thiocyanate ions (SCN) at either 70% to 100% or 0% to 30% of the surface. -The maximum amount of ) exists in this entity.

[0012] Another aspect of the perovskite layer, as described above, is a perovskite layer containing the compound represented by formula (I), Thiocyanic acid or its salt, Glycine derivatives represented by formula (II) or salts thereof, It is a perovskite layer that further contains [the specified element].

[0013] The second invention described in this specification relates to a laminate comprising any of the above-described perovskite layers and a surface treatment layer formed on the perovskite layer, wherein the surface treatment layer comprises an amine or a salt thereof.

[0014] A preferred example of the second invention is that the surface treatment layer contains a diamine or a salt thereof or diamine iodide, and more preferably contains ethylenediamine hydroiodide.

[0015] The third invention described in this specification relates to a solar cell comprising any of the perovskite layers or any of the laminates described above.

[0016] The fourth invention described in this specification relates to a perovskite precursor. This perovskite precursor comprises a compound represented by formula (I), thiocyanic acid or a salt thereof, and a glycine derivative represented by formula (II) or a salt thereof.

[0017] A preferred example of the above perovskite precursor is where M is Pb 2+ It contains thiocyanic acid or its salt, with Pb at a mole fraction. 2+ It contains between 1% and 10% of the total.

[0018] Preferred examples of the above perovskite precursors are: The salts of thiocyanate are Pb 2+ and Sn 2+It contains at least one of the following: a metal ion containing either or both of the above, an ammonium ion, and an ion containing an ionized amino group, along with a thiocyanate ion.

[0019] A preferred example of the perovskite precursor mentioned above is NH4SCN, which is a salt of thiocyanate.

[0020] A preferred example of the perovskite precursor described above is that the "glycine derivative or salt thereof" is glycine hydrochloride or glycine hydrobromide.

[0021] The fifth invention described in this specification relates to a method for producing a perovskite layer. This method involves the steps of preparing a perovskite precursor solution, The process includes the step of forming a perovskite layer using a perovskite precursor liquid. The perovskite precursor solution contains a glycine derivative represented by formula (II) or a salt thereof. The perovskite layer contains the compound represented by formula (I) and the glycine derivative represented by formula (II) or a salt thereof. In other words, the perovskite precursor solution contains the compound represented by formula (I) or its precursor and the glycine derivative represented by formula (II) or a salt thereof.

[0022] A preferred example of this method is a step in forming a perovskite layer using a perovskite precursor solution, in which the perovskite precursor solution is applied, followed by the application of a reverse solvent, thereby moving the glycine derivative represented by formula (II) or its salt toward the interface side of the perovskite layer.

[0023] The sixth invention described in this specification relates to a method for manufacturing a laminate. This method includes the steps of forming a perovskite layer by one of the perovskite layer manufacturing methods described above, and applying a surface treatment solution containing an amine or a salt thereof to the perovskite layer to form a surface treatment layer.

[0024] The surface treatment solution preferably further contains toluene. [Effects of the Invention]

[0025] This invention provides a perovskite layer that can achieve high short-circuit current density (Jsc) and energy conversion efficiency (PCE). This invention can provide solar cells and other devices having the above-mentioned perovskite layer. [Brief explanation of the drawing]

[0026] [Figure 1] Figure 1 is an SEM image, which replaces the drawing, showing a cross-section of the laminate including the perovskite layer and surface treatment layer obtained in Example 1. [Figure 2] Figure 2 is a graph that replaces the diagram, showing the characteristics of a solar cell without the addition of cyanate-based substances and glycine derivatives, and without a surface treatment layer. [Figure 3] Figure 3 is a graph that replaces the diagram showing the characteristics of the solar cell obtained in Example 1. [Figure 4] Figure 4 is a graph that replaces the diagram showing the IPCE spectrum of the solar cell obtained in Example 1. [Figure 5] Figure 5 is a graph that replaces the diagram showing the intensity distribution of EDA+ ions in TOF-SIMS measurements. EDA+ ions are mainly distributed from the surface up to 40 nm. [Figure 6] Figure 6 is a graph that replaces the diagram showing the intensity distribution of C2H4NO2- (glycine) ions in TOF-SIMS measurements. C2H4NO2- (glycine) ions are mainly distributed in the range from 790 nm to 860 nm from the surface (70 nm from the bottom). [Figure 7] Figure 7 is a graph that replaces the diagram showing the intensity distribution of SCN- ions in TOF-SIMS measurements. SCN- ions are mainly distributed in the range from 660 nm to 860 nm from the surface (200 nm from the bottom). [Figure 8]Figure 8 is a graph that replaces the diagram showing the intensity distribution of Cl- ions in TOF-SIMS measurements. Cl- ions are abundant from the surface up to ~50 nm and at the bottom (780 nm to 860 nm), but are also widely distributed in the interior. [Figure 9] Figure 9 is a graph that replaces the diagram showing the 3D distribution of each ion in the perovskite thin film calculated from the results of TOF-SIMS measurements. [Figure 10] Figure 10 is a graph that replaces the diagram showing the UPS measurement results of the laminate obtained in Example 1. (a) shows the cutoff region of secondary electrons, and (b) shows the HOMO region. [Figure 11] Figure 11 is a graph that replaces the diagram showing the band structure calculated from the UPS measurement results. [Figure 12] Figure 12 shows the normalized maximum power point tracking (MPPT) curves for unencapsulated control, EDAI2-treated, and EDAI2 / GlyHCl-treated devices operating in an inert atmosphere with AMI1.5G. [Figure 13] Figure 13 is a graph, instead of a diagram, that shows the variance of characteristic parameters of solar cells by forward and reverse JV scans of control, EDAI2-treated, and EDAI2 / GlyHCl-treated devices. [Figure 14] Figure 14 is a graph that replaces the diagram showing the characteristics of a solar cell using PAI. [Figure 15] Figure 15 is a graph that replaces the diagram showing the characteristics of a solar cell using PEAI. [Figure 16] Figure 16 is a graph that replaces the diagram to show the characteristics of a solar cell using β-alanine. [Figure 17] Figure 17 is a graph that replaces the diagram showing the characteristics of a solar cell using 4-ABA. [Figure 18] Figure 18 is a graph that replaces the diagram showing the characteristics of a solar cell using 5-AVA. [Figure 19] Figure 19 is a graph that replaces the diagram showing the characteristics of a solar cell using 4-AMBA. [Figure 20] Figure 20 is a graph that replaces the diagram to show the characteristics of a solar cell using PrySCN. [Figure 21] Figure 21 is a graph that replaces the diagram to show the characteristics of a solar cell using PEASCN. [Figure 22] Figure 22 is a graph that replaces the diagram showing the distribution of characteristic parameters of the solar cell obtained in Example 3. [Modes for carrying out the invention]

[0027] The embodiments for carrying out the present invention will be described below with reference to the drawings. The present invention is not limited to the embodiments described below, but also includes modifications made to the embodiments described below to the extent that is obvious to those skilled in the art. One invention described in this specification is characterized by employing one of the following: (1) including a glycine derivative or a salt thereof in the lower part of the perovskite layer; (2) including thiocyanic acid or a salt thereof in the lower part of the perovskite layer; and (3) providing a surface treatment layer containing an amine or a salt thereof (preferably a diamine or a salt thereof) on the upper surface of the perovskite layer. These can individually increase the photoelectric conversion efficiency of the perovskite layer, and when combined, they exert a synergistic effect, resulting in a higher photoelectric conversion effect while maintaining a high photoelectric conversion efficiency. Note that "lower" refers to the vertically downward direction during the manufacturing of the perovskite layer, and "upper" refers to the vertically upward direction during the manufacturing of the perovskite layer. Furthermore, "downward" can be rephrased as the substrate side when the perovskite layer is manufactured by coating and firing it onto the substrate, and "upward" can be rephrased as the side opposite to the substrate when the perovskite layer is manufactured by coating and firing it onto the substrate.

[0028] Perovskite layer The perovskite layer (light-absorbing layer) is a layer that absorbs light and performs photoelectric conversion by moving excited electrons. This perovskite layer contains a compound represented by formula (I) (a compound having a perovskite structure). Preferably, it also contains a glycine derivative or a salt thereof, or thiocyanic acid or a salt thereof, as described later. Equation (I) is, AM m X n ...(I). A is a methylammonium cation (CH3NH3 + ), formamidinium cation (NH2CHNH2 + ) and cesium cation (Cs + A may include one or more of the following: A may include only one or two of these; A may include all three of these, or consist of all three of these. M is Pb 2+ and Sn 2+ It is a metal ion containing either or both of the following: M is Pb 2+ It is preferable that it contains Pb 2+ and Sn 2+ It may include both, (effectively) Pb 2+ and Sn 2+ It's okay if it's from there. X is F - ,Cl - ,Br - , and I - X is one or more of the following types. - That's fine. m is between 0.8 and 1.2. An example of m when M consists only of divalent values ​​is 1. n is between 2.8 and 3.2. An example of n is 3. The compound represented by formula (I) may also be a neutral compound containing the cation or anion mentioned above.

[0029] Examples of compounds represented by formula (I) include Cs l1 FA l2 MA l3 Pb m1 Sn m2 I n1Here, l1+l2+l3=1, m1+m2=0.8~1.2 (preferably 1), and n1 is 2.8~3.2 (preferably 3). FA is formamidinium (NH2CHNH2), and MA is methylammonium (CH3NH3).

[0030] Examples of compounds represented by formula (I) include Cs 0.10 FA 0.60 MA 0.30 Pb 0.5 Sn 0.5 I3, Methylammonium lead iodide (CH3NH3PbI3: abbreviated as "MAPbI3"), (CH3NH3)2Pb3I8: abbreviated as "MA2Pb3I8"), Methylammonium lead bromide (CH3NH3PbBr3: abbreviated as "MAPbBr3"), Formamidinium lead iodide ((NH2)2CHPbI3: abbreviated as "FAPbI3"), and Formamidinium lead bromide ((NH2)2CHPbBr3: abbreviated as "FAPbBr3"), Iodine These are methylammonium tin bromide (CH3NH3SnI3: abbreviated as "MASnI3"), (CH3NH3)2Sn3I8: abbreviated as "MA2Sn3I8"), methylammonium tin bromide (CH3NH3SnBr3: abbreviated as "MASnBr3"), formamidinium tin iodide ((NH2)2CHSnI3: abbreviated as "FASnI3"), and formamidinium tin bromide ((NH2)2CHSnBr3: abbreviated as "FASnBr3").

[0031] Thiocyanate ions (SCN) at positions 20% and 80% from the surface of the perovskite layer (or the interface with other layers in the case of a laminate) - The existence values ​​of ) are each d SCN20% and d SCN80% The abundance values ​​can be determined using the values ​​at a position 20% below the center of gravity and a position 80% below the center of gravity, with respect to the center of gravity on the surface of the perovskite layer. In this specification, the abundance values ​​can be determined in the same manner. Furthermore, the abundance values ​​can be measured according to the examples described later. Then, a preferred example of a perovskite layer is d SCN80% ,d SCN20%It is more than 5 times or less than 1 / 5 of that. If the top surface during the manufacturing of the perovskite layer is considered the surface, d SCN80% ,d SCN20% This is more than five times that amount. SCN80% ,d SCN20% It can be 5 times or more but 1000 times or less, 5 times or more but 100 times or less, 5 times or more but 50 times or less, or 10 times or more but 1000 times or less. In the perovskite layer described above, thiocyanate ions become abundant in the lower region during manufacturing. In this way, the perovskite layer is formed slowly. It is thought that this results in the growth of a perovskite layer with good photoelectric conversion efficiency.

[0032] A preferred example of the perovskite layer described above is a perovskite layer with thiocyanate ions (SCN) at either 70% to 100% or 0% to 30% of the surface. - The maximum abundance of thiocyanate ions (SCN) exists in the perovskite layer. If the top surface during manufacturing is considered the surface, then thiocyanate ions (SCN) are located at a position between 70% and 100% from the surface of the perovskite layer. - It is preferable that the maximum abundance of thiocyanate ions (SCN) is present. Note that 100% from the surface of the perovskite layer means the bottom surface of the perovskite layer. This specification also means that thiocyanate ions are abundant in the lower region during the manufacturing of the perovskite layer. - The maximum abundance of ) may be located at a position between 75% and 99% of the surface of the perovskite layer, or at a position between 80% and 95% of the surface.

[0033] Thiocyanic acid or its salt Thiocyanate (HSCN) or its salts contain thiocyanate ions (SCN). - ) The source is not particularly limited. Examples of thiocyanate salts are any of the following:

[0034] [ka]

[0035] A preferred example of a thiocyanate salt is Pb 2+ and Sn 2+ A metal ion containing either or both of the following, an ammonium ion, and at least one ion containing an ionized amino group (cation source), and a thiocyanate ion (SCN - It consists of ).

[0036] Preferred examples of thiocyanic acid or its salts are Pb(SCN)2, guanidine thiocyanate, and NH4SCN. Among these, NH4SCN is preferred as the thiocyanic acid salt.

[0037] Glycine derivatives or salts thereof A preferred example of a perovskite layer is one containing a glycine derivative represented by formula (II), or a salt of the glycine derivative represented by formula (II). Preferably, the maximum total abundance of the glycine derivative represented by formula (II), its salt, and their ions (ions derived from the glycine derivative and ions derived from the salt) is located at either 70% to 100% or 0% to 30% from the surface of the perovskite layer. This maximum value represents the value at which the sum of the abundance of the glycine derivative represented by formula (II), the salt, and the ions of the glycine derivative contained in the perovskite layer is maximized. If the top surface of the perovskite layer during manufacturing is considered the surface, it is preferable that the maximum total abundance of the glycine derivative represented by formula (II), its salt, and their ions is located at 70% to 100% from the surface of the perovskite layer. The above maximum value may be located at 75% to 99% from the surface of the perovskite layer, or at 80% to 95% from the surface.

[0038] The glycine derivatives represented by formula (II) are as follows: [ka] In formula (II), R 1 These are C1-C5 alkylene groups, C6-C10 An arylene group, a group represented by the formula -C(=NH)NHCH2-, or -R 3 R 4 represents a group represented by -. R 1 is preferably a C1-C5 alkylene group, and preferably a methylene group. R 2 represents a carbon atom, P(OH), or S(=O). R 2 is preferably a carbon atom. R 3 and R 4 are R 3 represents a C1-C5 alkylene group, R 4 represents a C6-C 10 arylene group, or R 3 represents a C6-C 10 arylene group, R 4 represents a C1-C5 alkylene group.

[0039] The C1-C5 alkylene group means an alkylene group which may have a straight chain or a branched chain having 1 to 5 carbon atoms. Examples of the C1-C5 alkylene group are a methylene group, a methylmethylene group, an ethylene group, a propylene group, a trimethylene group, a 1-methylethylene group, a tetramethylene group, a 1-methyltrimethylene group, a 2-methyltrimethylene group, a 3-methyltrimethylene group, a 1-methylpropylene group, a 1,1-dimethylethylene group, a pentamethylene group, a 1-methyltetramethylene group, a 2-methyltetramethylene group, a 3-methyltetramethylene group, a 4-methyltetramethylene group, a 1,1-dimethyltrimethylene group, a 2,2-dimethyltrimethylene group, and a 3,3-dimethyltrimethylene group.

[0040] C6-C 10 The arylene group means a divalent group formed by removing 2 hydrogen atoms bonded to the ring from an aromatic hydrocarbon having 6 to 10 carbon atoms or a divalent group having 6 to carbon atoms containing a monovalent aromatic hydrocarbon group and an alkylene group bonded to the ring of the monovalent aromatic hydrocarbon. C6-C 10 Examples of the ring constituting the arylene group are a benzene ring and a naphthalene ring. C6-C 10Examples of allylene groups include phenylene, naphthylene, and benzylene groups.

[0041] An example of a glycine derivative represented by formula (II), or a salt of a glycine derivative represented by formula (II), is one of the following:

[0042] [ka]

[0043] Preferred examples of glycine derivatives or salts thereof are glycine derivatives or salts thereof having a methylammonium group (-CH2-NH2) that can penetrate structural defects on the surface of the perovskite layer. By using a glycine derivative or salt thereof having a methylammonium group, it is thought that the portion containing the methylammonium group will bond to the surface of the perovskite layer. This can reduce defects on the surface of the perovskite layer. Furthermore, by positioning the portion containing the carboxyl group of the glycine derivative away from the surface of the perovskite layer, an electrical bipolar state is created on the surface. This is thought to facilitate the movement of holes generated in the perovskite layer to the positive electrode side (hole transport layer side). Examples of glycine derivatives are glycine, alanine, 4-ABA (4-aminobutyric acid), 5-AVA (5-aminovaleric acid), and 4-AMBA (4-aminomethylbenzene acid). Furthermore, preferred examples of glycine derivatives or salts thereof are glycine hydrochloride and glycine hydrobromide.

[0044] The perovskite layer may contain the compound represented by formula (I) and the glycine derivative represented by formula (II) or a salt thereof. The perovskite layer may contain the compound represented by formula (I), thiocyanic acid or a salt thereof, and the glycine derivative represented by formula (II) or a salt thereof. The other compositions contained in the perovskite layer may be those of known perovskite layers. The thickness and size of the perovskite layer may also be those of known standards.

[0045] Perovskite precursors The perovskite precursor contains a compound represented by formula (I), and includes either or both thiocyanic acid or a salt thereof, and a glycine derivative represented by formula (II) or a salt thereof. The compound represented by formula (I) in the perovskite precursor may exist in the perovskite precursor in its compound form, or in the perovskite precursor with some ions removed. A preferred example of the perovskite precursor is one in which M is Pb 2+ It contains thiocyanic acid or its salt, with Pb at a mole fraction. 2+ It contains 1% to 10% of thiocyanic acid or its salt, in mole fraction of Pb 2+ The perovskite precursor may contain 2% to 8%, or 3% to 7%. The composition of the perovskite layer can be appropriately adopted for the perovskite precursor. In the perovskite precursor, the compound represented by formula (I), thiocyanic acid or its salt, and the glycine derivative represented by formula (II) or its salt are each contained in, for example, 0.5M to 4M (preferably 1M to 3M). The content of thiocyanic acid or its salt may be 3 times or less the amount of the compound represented by formula (I) in molar ratio, 0.5 to 2 times, or 0.7 to 1.5 times. The content of the glycine derivative or its salt may be 3 times or less the amount of the compound represented by formula (I) in molar ratio, 0.5 to 2 times, or 0.7 to 1.5 times.

[0046] Laminate The laminate includes a perovskite layer and a surface treatment layer formed on the perovskite layer. The surface treatment layer is a layer formed on the surface of the perovskite layer (the upper surface during the manufacturing of the perovskite layer). By forming the surface treatment layer, a synergistic effect with the perovskite layer can be achieved, as shown in the examples described later, to further increase the photoelectric conversion efficiency. This surface treatment layer contains an amine or a salt thereof. Examples of amines or salts of amines contained in the surface treatment layer are any of the following:

[0047] [ka]

[0048] The surface treatment layer can be formed by applying a surface treatment solution containing an amine or a salt thereof to the perovskite layer, but the use of an amine salt is preferred, and the use of a diamine salt is particularly preferred. In addition to the diamine salt, the surface treatment solution can use an alcohol such as IPA that is soluble in these, but it is even more preferable to use one that contains toluene as a cosolvent. As shown in the examples, when a diamine salt is particularly present in the surface treatment layer, n-type properties are exhibited compared to the internal perovskite layer. In particular, the presence of a glycine derivative or a salt thereof localized in the perovskite layer, and the presence of a diamine salt particularly in the surface treatment layer of the perovskite layer, enables the realization of a pin-type electronic structure, which is thought to lead to an improvement in solar cell characteristics.

[0049] The coating solution for the surface treatment layer comprises, for example, an amine or a salt of an amine and a solvent. The content of the amine or salt of an amine may be adjusted as appropriate. An example of a solvent is one containing an alcohol and an aromatic hydrocarbon. An example of an alcohol is IPA (isopropyl alcohol). The amount of alcohol per 1 g of amine or diamine salt is, for example, 100 ml to 10 l, or 0.5 l to 2 l. An example of an aromatic hydrocarbon is toluene. The amount of aromatic hydrocarbon per 1 g of amine or diamine salt is, for example, 100 ml to 10 l, or 0.5 l to 2 l. Preferred examples of amines or amine salts are amines or amine salts containing methylammonium groups that can penetrate structural defects on the perovskite layer surface. Preferred examples of monoamine salts containing methylammonium groups are propyleneamine hydroiodide and phenylethylamine hydroiodide. As mentioned above, preferred examples of amines or amine salts are diamines or diamine salts. Preferred examples of diamines or diamine salts have two amine moieties as ammonium salts (e.g., ammonium iodide), with the two ammonium salts linked by a two- or three-carbon linking group. By using diamines or diamine salts containing methylammonium groups, the moieties containing methylammonium groups bond to the perovskite layer surface. This reduces defects on the perovskite layer surface. Furthermore, by positioning the amine-containing moieties away from the perovskite layer surface, an electrical bipolar state is created on the surface. This makes it easier for electrons generated in the perovskite layer to move to the negative electrode side (electron transport layer side). Preferred examples of diamine salts are diamine iodides, and preferred examples of diamine iodides are ethylenediamine hydroiodide and propylamide imide. Furthermore, the surface treatment solution may contain an acid having a carboxyl group in addition to the amine. In this case, the acid is preferably an acid that has electron transport properties. Also, when an electron transport layer is formed on the perovskite layer via the surface treatment layer in a solar cell, the acid is preferably an acid having a structure similar to the material contained in the electron transport layer. For example, if the electron transport layer contains a fullerene derivative, the acid is preferably a fullerene structure. A preferred example of the acid is C60 pyrrolidinetrisic acid.

[0050] Method for producing a perovskite layer Next, we will explain the method for producing the perovskite layer. The perovskite layer can be formed by a method comprising the steps of preparing a perovskite precursor solution and forming a perovskite layer using the perovskite precursor solution. It is preferable to coat the perovskite precursor solution and then coat the reverse solvent to move either or both of (1) the glycine derivative represented by formula (II) or its salt and (2) thiocyanic acid or its salt to the interface side of the perovskite layer. This method allows for a time of 10 seconds or more between coating the solution and adding the poor solvent (preferably 30 seconds or more, 1 minute or more, or 2 minutes or more, but may be 5 minutes or less). Thus, this method can be used for mass production such as roll-to-roll because it allows for a relatively sufficient time before adding the poor solvent. By combining this method for manufacturing the perovskite layer with known methods, a solar cell can be obtained. The substrate may already have another film formed on it, and the perovskite layer may be formed on top of that film. An example of the film thickness of the coated layer is 10 nm to 1000 nm. The film thickness may also be 50 nm to 500 nm, 100 nm to 500 nm, or 250 nm to 500 nm.

[0051] solar cells Next, we will describe solar cells (particularly perovskite solar cells) containing the compound of the present invention.

[0052] The perovskite solar cell of the present invention comprises, for example, a transparent electrode, a (hole) blocking layer, an electron transport layer, a perovskite layer (light absorption layer), a hole transport layer, and a metal electrode in this order. The (hole) blocking layer is any layer. The order of the electron transport layer, perovskite layer (light absorption layer), and hole transport layer may also be reversed. A surface treatment layer may be provided on any surface of the perovskite layer (light absorption layer).

[0053] transparent electrode Since the transparent electrode serves as a support for the electron transport layer and also functions to extract electric current (holes) from the perovskite layer (light absorption layer) via the (electron) blocking layer, a conductive substrate is preferred, and a transparent conductive layer having light-transmitting properties that allows light contributing to photoelectric conversion to pass through is preferred.

[0054] Examples of transparent conductive layers include tin-doped indium oxide (ITO) films, impurity-doped indium oxide (In2O3) films, impurity-doped zinc oxide (ZnO) films, fluorine-doped tin dioxide (FTO) films, and laminated films formed by laminating these. The thickness of these transparent conductive layers is not particularly limited, but it is generally preferable to adjust it so that the resistance is 5 to 15 Ω / □. The transparent conductive layer can be obtained by known film formation methods depending on the material being molded.

[0055] The transparent conductive layer may be covered with a translucent coating as needed to protect it from the outside. Examples of such translucent coatings include resin sheets such as fluororesin, polyvinyl chloride, and polyimide; inorganic sheets such as white glass and soda glass; and hybrid sheets made by combining these materials. The thickness of these translucent coatings is not particularly limited, but it is generally preferable to adjust it so that the resistance is 5 to 15 Ω / □.

[0056] (Electron) blocking layer The (electron) blocking layer is a layer provided to prevent electron leakage and suppress reverse current to improve solar cell characteristics (especially photoelectric conversion efficiency), and is preferably provided between the transparent electrode and the perovskite layer (light absorption layer). The (electron) blocking layer is preferably made of a metal oxide such as NiOx or an organic semiconductor such as PEDOT:PSS, and more preferably a layer in which the surface of the transparent electrode is smoothly and densely covered with a p-type semiconductor. "Dense" means that the p-type semiconductor in the hole transport layer is densely packed. Note that pinholes, cracks, etc. may exist as long as the transparent electrode and the hole transport layer are not electrically connected.

[0057] The thickness of the electron blocking layer is, for example, 1 to 100 nm. From the viewpoint of electron injection efficiency into the electrode, a thickness of 20 nm to 50 nm is more preferable.

[0058] The (electron) blocking layer is formed on the transparent electrode described above. When an organic semiconductor is used as the (hole) blocking layer, a commercially available PEDOT:PSS aqueous solution can be spin-coated according to known methods (e.g., Nat. Commun. 2020, 11, 3008, etc.).

[0059] Subsequently, the resulting substrate can be heated in air and in an inert gas atmosphere to create a denser film.

[0060] An aqueous solution of PEDOT:PSS can be used directly after filtering a commercially available PEDOT:PSS solution (Heraeus, Clevious P VP.Al 4083) through a 0.45 μm PTFE filter. The heating and drying conditions are preferably at a temperature of 30-150°C, more preferably 100-150°C. Furthermore, it is even more preferable to heat and dry the solution in air, then transfer it to a glove box filled with an inert gas (such as Ar), and heat and dry it further at 100-150°C for about 30 minutes.

[0061] Electron transport layer (hole blocking layer) The electron transport layer (hole blocking layer) is formed to selectively collect electrons from the carriers generated in the perovskite layer (light absorption layer) and to improve photoelectric conversion efficiency. The electron transport layer may be formed on the perovskite layer by spin coating or vacuum deposition, but when using C60 or the like, it is preferable to form it on the perovskite layer by vacuum deposition. In addition, a buffer layer such as BCP can be deposited to reduce the contact resistance between the electron transport layer and the electrode fabricated on it. The film thicknesses of the electron transport layer (C60) and the buffer layer (BCP) may be 1 to 100 nm and 1 to 50 nm, but 10 to 50 nm and 1 to 30 nm are more preferable, 20 to 40 nm and 3 to 10 nm are even more preferable, and 20 nm and 8 nm are particularly preferable.

[0062] Perovskite layer (light-absorbing layer) In a perovskite solar cell, the perovskite layer (light-absorbing layer) is a layer that absorbs light and performs photoelectric conversion by moving excited electrons. The perovskite layer (light-absorbing layer) contains perovskite material or a perovskite complex. The perovskite layer can be manufactured according to the method described above. It is preferable to achieve mass production of the perovskite layer by roll-to-roll. The mixture is preferably applied to the substrate by spin coating, dip coating, screen printing, roll coating, die coating, transfer printing, spray coating, slit coating, etc., preferably by spin coating.

[0063] The substrate is not particularly limited as long as it can support the film to be deposited. The material of the substrate is also not particularly limited as long as it does not hinder the objective of the present invention, and may be a known substrate, and either organic or inorganic compounds can be used. For example, insulating substrates, semiconductor substrates, metal substrates, and conductive substrates (including conductive films) can all be used. Furthermore, substrates on which at least one of the following films—a metal film, a semiconductor film, a conductive film, and an insulating film—is formed on part or all of their surface can also be suitably used.

[0064] Examples of constituent metals for the metal film include one or more metals selected from gallium, iron, indium, aluminum, vanadium, titanium, chromium, rhodium, nickel, cobalt, zinc, magnesium, calcium, silicon, yttrium, strontium, and barium. Examples of constituent materials for the semiconductor film include elemental elements such as silicon and germanium, and chemical compounds containing elements from groups 3 to 5 and 13 to 15 of the periodic table. Examples of materials include alloys, metal oxides, metal sulfides, metal selenides, and metal nitrides. Examples of constituent materials for the conductive film include tin-doped indium oxide (ITO), fluorine-doped indium oxide (FTO), zinc oxide (ZnO), aluminum-doped zinc oxide (AZO), gallium-doped zinc oxide (GZO), tin oxide (SnO2), indium oxide (In2O3), and tungsten oxide (WO3). Examples of constituent materials for the insulating film include aluminum oxide (Al2O3), titanium oxide (TiO2), silicon oxide (SiO2), silicon nitride (Si3N4), and silicon oxynitride (Si4O5N3), with insulating films made of insulating oxides being preferred, and titanium oxide films being more preferred. In the present invention, conductive films made of conductive oxides or insulating oxides are preferred, with tin-doped indium oxide (ITO) films and fluorine-doped indium oxide (FTO) films being more preferred.

[0065] The substrate can be any shape and is effective for any shape, such as flat plates or discs, fibrous, rod-shaped, cylindrical, prismatic, tubular, spiral, spherical, or ring-shaped, and porous structures can also be used. In this invention, a plate-shaped substrate is preferred. The thickness of the substrate is not particularly limited in this invention, but is preferably 0.1 μm to 100 mm, and more preferably 1 μm to 10 mm. If the substrate is a glass substrate, an example of the substrate thickness is 0.1 mm to 1 cm, but may also be 0.5 mm to 3 mm, or 0.5 mm to 2 mm. If the substrate is a resin substrate such as a PET substrate or a biaxially oriented polyethylene 2,6-naphthalate (PEN) substrate, an example of the substrate thickness is 1 μm to 200 μm, but may also be 5 μm to 100 μm, or 10 μm to 100 μm.

[0066] The thickness of the perovskite layer (light-absorbing layer) is preferably 50 to 1000 nm, and more preferably 200 to 800 nm, from the viewpoint of balancing light absorption efficiency and exciton diffusion length, and the absorption efficiency of light reflected by the transparent electrode. In the present invention, the thickness of the perovskite layer (light-absorbing layer) is preferably in the range of 100 to 1000 nm, and more preferably in the range of 250 to 500 nm. Specifically, the lower limit of the thickness of the perovskite layer (light-absorbing layer) of the present invention is preferably 100 nm or more (particularly 400 nm) or more, and the upper limit is preferably 1000 nm or less (particularly 900 nm or less). The thickness of the perovskite layer (light-absorbing layer) of the present invention is measured by a cross-sectional scanning electron microscope (cross-sectional SEM) of the film made of the complex of the present invention.

[0067] Furthermore, the flatness of the perovskite layer (light-absorbing layer) of the present invention is preferably such that the height difference in a 500 nm × 500 nm horizontal area of ​​the surface measured by scanning electron microscopy is 50 nm or less (-25 nm to +25 nm), and more preferably 40 nm or less (-20 nm to +20 nm). This makes it easier to balance the light absorption efficiency and the exciton diffusion length, and further improves the absorption efficiency of light reflected by the transparent electrode. The flatness of the perovskite layer (light-absorbing layer) is measured using a cross-sectional scanning electron microscope (cross-sectional SEM) of the perovskite layer (light-absorbing layer) of the present invention, with an arbitrarily determined measurement point as the reference point, and the difference between the point with the largest film thickness and the point with the smallest film thickness as the upper limit and the difference between the point with the largest film thickness and the reference point as the lower limit, with the flatness of the perovskite layer (light-absorbing layer) of the present invention being measured.

[0068] metal electrode The metal electrode is positioned opposite the transparent electrode and formed on the hole transport layer, enabling charge exchange with the hole transport layer. As the metal electrode, known materials used in this industry can be used, such as platinum, titanium, stainless steel, aluminum, gold, silver, nickel, or alloys thereof. Among these, materials that can be formed by methods such as vapor deposition are preferred, as they allow for electrode formation in a dry atmosphere. Perovskite solar cells with layer configurations other than those described above can also be manufactured by similar methods.

[0069] Organic electroluminescent elements (organic EL elements) Organic EL elements are known elements, as described in, for example, Japanese Patent Publication No. 2017-123352 and Japanese Patent Publication No. 2015-071619, and their manufacturing methods are also known. An example of an organic EL element includes a substrate, an anode, a cathode, and an organic layer disposed between the anode and the cathode. The organic layer is constructed by stacking, in order from the anode side, a hole injection layer, a hole transport layer, an emissive layer, an electron transport layer, and an electron injection layer. The compound of the present invention can be used as an electron transport material in the electron transport layer.

[0070] The present invention also provides a method for manufacturing a solar cell. This method includes the steps of forming a hole transport (electron blocking) layer on a substrate using the perovskite layer manufacturing method described above, forming a perovskite layer on the hole transport layer, forming an electron transport (hole blocking) layer on the perovskite layer, and forming electrodes on the electron transport layer. [Examples]

[0071] The present invention will be described below based on examples. The present invention is not limited to the following examples, and includes additions and modifications of techniques known to those skilled in the art.

[0072] Ingredients: Unless otherwise specified, all ingredients were commercially available and used as is. Methylammonium iodide (MAI, > 99%), formamidine iodide (FAI, > 98%), bathocuproine (BCP), lead(II) iodide (PbI2, 99.99%, trace metals basis), and cesium iodide (CsI, > 99%) were supplied by Tokyo Chemical Industry Co., Ltd. (TCI). Ammonium thiocyanate (NH4SCN, 99.99% trace metals basis), tin(II) fluoride (SnF2, 99%), tin(II) iodide (SnI2, beads, 99.99%, trace metals basis), ethylenediamine hydroiodide (EDAI2, > 98%), and glycine hydrochloride (GlyHCl, > 99%) were supplied by Sigma-Aldrich. The PEDOT:PSS aqueous solution (Clevious PVP AI 4083) used was that of Heraeus Co., Ltd. 60(Sublimed, 99.99%) was from ATR Company. Dehydrated dimethyl sulfoxide (DMSO, super dehydrated) and dehydrated isopropyl alcohol (IPA, super dehydrated) were from FUJIFILM Wako Pure Chemical Co., and dehydrated dimethylformamide (DMF) and chlorobenzene were from Kanto Chemical Co. All solvents were degassed by argon gas bubbling for 1 hour, and then further dehydrated immediately before use in a glove box filled with argon gas (H2O, O2 < 0.1 ppm) using mock sieves.

[0073] Fabrication of perovskite thin films Perovskite thin films were fabricated in a glove box filled with argon gas (H2O, O2 < 0.1 ppm). Cs 0.1 FA 0.6 MA 0.3 Sn 0.5 Pb 0.5 The perovskite semiconductor precursor solution having composition I3 was prepared by diluting CsI (46.77 mg, 0.180 mmol), FAI (185.73 mg, 1.08 mmol), MAI (85.84 mg, 0.540 mmol), SnI2 (335.27 mg, 0.900 mmol), PbI2 (414.91 mg, 0.900 mmol), and SnF2 (14.10 mg, 0.090 mmol) to a concentration of 1.8 M using a mixed solvent of 0.25 mL DMSO and 0.75 mL DMF. Furthermore, 2 mol% of NH4SCN (2.74 mg, 0.036 mmol) and glycine hydrochloride (4.02 mg, 0.900 mmol) were added as additives to the perovskite precursor material. The precursor solution was stirred at 45°C for 40 minutes, and then filtered through a 0.20 μm PTFE filter immediately before spin coating. 200 μL of the precursor solution was deposited at room temperature using the following two-step spin coating method. The first step was 200 rpm s -1After the acceleration, it spins at 1000 rpm for 10 seconds, and then the second stage is at 1000 rpm s -1 After acceleration, the substrate was spun at 4000 rpm for 40 seconds. Twenty seconds before the end of the second spin, 400 μL of room temperature chlorobenzene was dropped onto the surface of the spinning thin film substrate. After spin coating, the perovskite thin film substrate was quickly moved onto a hot plate and heated at 100 °C for 10 minutes, followed by heating at 65 °C for at least 10 minutes. As a surface treatment on the resulting perovskite thin film, a 120 μL solution of EDAI2 (1 mg dissolved in a mixed solution of 1 mL IPA and 1 mL of toluene) was dropped onto the perovskite thin film, spin coated at 4000 rpm for 20 seconds, and then heated at 100 °C for 2 minutes.

[0074] Other thiocyanate ions (SCN ― Similarly, when other glycine derivatives were used as additives, the additive was added to the precursor solution to a concentration of 2 mol% relative to the perovskite precursor and then spin-coated. When diamine halide salts other than ethylenediamine hydroiodide (EDAI2) were used for surface treatment of the perovskite thin film, the solution was spin-coated onto the perovskite thin film and heated, as in the case of EDAI2.

[0075] Fabrication of solar cell devices Glass / FTO substrate (10 Ω sq ―1After patterning with zinc powder and HCl (6 M in de-ionized water) on a Geomatec Co., Ltd. substrate, it was cleaned in an ultrasonic cleaner for 15 minutes each in the following order: water, acetone, cleaning solution (Semico Clean 56, Furuuchi Chemical), water, and isopropyl alcohol, and then dried using an air gun. After cleaning the surface of organic matter by plasma cleaning, a PEDOT:PSS aqueous solution (Heraeus, Clevious PV VP.Al 4083), filtered through a 0.45 μm PTFE filter, was spin-coated onto an FTO substrate (500 rpm for 10 seconds, followed by 4000 rpm for 60 seconds), and heated at 140 °C for 20 minutes. The substrate was then moved to a glove box filled with Ar (H2O, O2 < 0.1 ppm) and heated at 140 °C for 30 minutes. A perovskite thin film was fabricated on the obtained PEDOT:PSS (film thickness 30 nm) using the method described above. Subsequently, a 20 nm C layer was deposited by vacuum deposition. 60 (0.01 nm s ―1 ) and 8 nm BCP (0.01 nm s ―1 ) are deposited on each, and finally a 100 nm silver electrode (0.005 nm s ―1 The pattern was created using a metal mask and then vapor-deposited.

[0076] Physical property measurement Scanning electron microscope (SEM) images were measured using an S8010 (Hitachi High-Technologies Co.). The photocurrent-voltage (JV) curves of the solar cells were measured in a glove box filled with N2 gas (H2O, O2 < 0.1 ppm) using an OTENTO-SUN-P1G solar simulator (BUNKOUKEIKI Co., Ltd.) and a Keithley 2400 source meter, with a metal mask (0.0985 cm²). 2 The measurements were taken using ( ). The intensity of the simulated sunlight was corrected using a BS520 silicon photodiode. External quantum efficiency (EQE) and internal quantum efficiency (IQE) spectra were measured using the SMO-250III system (BUNKOUKEIKI Co., Ltd.) equipped with an SM-250 diffuse reflection unit. Light intensity was corrected using a SiPD S1337-1010BQ silicon photodiode.

[0077] Figure 1 is an SEM image, replacing a drawing, showing a cross-section of the laminate including the perovskite layer and surface treatment layer obtained in Example 1. The thickness of the perovskite layer was 860 nm. Figure 2 is a graph that replaces the diagram, showing the characteristics of a solar cell without the addition of cyanate-based substances and glycine derivatives, and without a surface treatment layer. Figure 3 is a graph that replaces the diagram showing the characteristics of the solar cell obtained in Example 1. Figure 4 is a graph that replaces the diagram showing the IPCE spectrum of the solar cell obtained in Example 1.

[0078] Table 1 shows the surface treatment effects of perovskite layers using EDAI and similar compounds. Table 2 shows the additive effects of NH4SCN and similar compounds on perovskite layers. Table 3 shows the additive effects of glycine hydrochloride and similar compounds on perovskite layers. Table 4 shows the synergistic effect of the NH4SCN and glycine hydrochloride additives and the EDAI2 surface treatment.

[0079] [Table 1]

[0080] [Table 2]

[0081] [Table 3]

[0082] [Table 4]

[0083] Time-of-flight secondary ion mass spectrometry (TOF-SIMS) measurement Measurements were taken using TOF.SIMS 5 (IONTOF GmbH, Munster, Germany) in burst alignment mode. A 50 kV Bi3 with a pulse width of 125 ns was used. 2+ Data was integrated using the primary ion beam. To reduce damage to the sample, the Primary ion dose density (PIDD) was set to approximately 5 × 10⁻¹⁶ in each measurement cycle. 11 ions / cm 2 The following measurements were performed. For depth profiling, a 10 kV argon gas cluster ion beam (Ar-GCIB) with a size of approximately 1200 was used as the sputter ion beam. The raster area was 30 μm × 30 μm for the primary ion beam and 500 μm × 500 μm for the sputter ion beam. Mass spectrometry was performed on the central part of the sputtered area (100 μm × 100 μm).

[0084] Figure 5 shows EDA in TOF-SIMS measurement. + This graph replaces diagrams showing the ion intensity distribution. (EDA) + Ions are mainly distributed from the surface up to 40 nm. Figure 6 shows the results of C2H4NO2 measurements using TOF-SIMS. - This is a graph that replaces the diagram showing the intensity distribution of (glycine) ions. C2H4NO2 - (Glycine) ions are mainly distributed in the range from 790 nm to 860 nm from the surface (70 nm from the bottom). Figure 7 shows SCN in TOF-SIMS measurement. - This graph replaces the diagram showing the ion intensity distribution. (SCN) -Ions are mainly distributed in the range from 660 nm to 860 nm from the surface (200 nm from the bottom). Figure 8 shows the results of the TOF-SIMS measurement of Cl - This graph replaces the diagram showing the ion intensity distribution. - Ions are abundant in the range from the surface to about 50 nm and towards the bottom (780 nm to 860 nm), but they are also widely distributed within the interior. Figure 9 is a graph that replaces the diagram showing the 3D distribution of each ion in the perovskite thin film calculated from the results of TOF-SIMS measurements.

[0085] Ultraviolet photoelectron spectroscopy (UPS) measurement UPS measurements were performed using a PHI5000 VersaProbe II (ULVAC-PHI Inc.) with He I excitation (21.2 eV).

[0086] Figure 10 is a graph that replaces the diagram showing the UPS measurement results of the laminate obtained in Example 1. (a) shows the cutoff region of secondary electrons, and (b) shows the HOMO region. Figure 11 is a graph that replaces the diagram showing the band structure calculated from the UPS measurement results.

[0087] Figure 12 shows the normalized maximum power point tracking (MPPT) curves for unencapsulated control, EDAI2-treated, and EDAI2 / GlyHCl-treated devices operating in an inert atmosphere with AMI 1.5G. Initial efficiencies were 14.8%, 18.2%, and 20.1%, respectively. Table 5 shows the PL lifetime, PL intensity, peak energy, and FWHM (full width at half maximum) of the PL peak of the perovskite film formed on the substrate.

[0088] [Table 5]

[0089] Figure 13 is a graph, instead of a diagram, showing the variance of device parameters by forward and reverse JV scans of control, EDAI2-treated, and EDAI2 / GlyHCl-treated devices. Six samples were used for each condition. [Examples]

[0090] In this example, the properties of solar cells obtained using various surface treatment agents, glycine derivatives, and thiocyanic acid were confirmed. As a surface treatment agent, PAI (propylamine hydroiodide; CH3CH2CH2NH3) is used instead of EDAI2. + I - ),PEAI (phenylethylamine hydroiodide; PhCH2CH2NH3 + I - The characteristics of solar cells prepared in the same manner as in Example 1 are shown in Figures 14 to 21, except that the following were used: alanine (β-alanine), 4-ABA (4-aminobutyric acid), 5-AVA (5-aminovaleric acid), and 4-AMBA (4-aminomethylbenzene acid) were used instead of glycine hydrochloride as glycine derivatives, and PrySCN (pyrrolidinium thiocyanate) and PEASCN (phenethylammonium thiocyanate) were used instead of NH4SCN as thiocyanates. [Examples]

[0091] First, the perovskite film was prepared as follows. The experiment was conducted in a glove box filled with Ar (H2O, O2 < 0.1 ppm). Cs 0.1 FA 0.6 MA 0.3 Sn 0.5 Pb 0.5The I3 perovskite precursor solution was prepared by mixing CsI (48.06 mg, 0.185 mmol), FAI (190.89 mg, 1.11 mmol), MAI (88.23 mg, 0.555 mmol), and SnI2 (334.58 mg, 0.925 mmol), PbI2 (426.43 mg, 0.925 mmol), SnF2 (14.50 mg, 0.0925 mmol), GlyHCl (5.16 mg, 0.04625 mmol), and NH4SCN (2.82 mg, 0.037 mmol) in a 1.85 M solution of 0.25 mL DMSO and 0.75 mL LDMF. The precursor solution was stirred at 45°C for 40 minutes and filtered through a 0.20 μm PTFE filter before use. 200 μL of the precursor solution was applied to a substrate for spin coating. A two-stage spin coating program was used. The first step was 1000 rpm for 10 seconds, followed by acceleration at 200 rpm s -1 The second step is to maintain a constant speed of 4000 rpm for 40 seconds, with acceleration at 1000 rpm. -1 The procedure involved using chlorobenzene (400 μL) at room temperature as the poor solvent. Chlorobenzene was rapidly dropped onto the surface of the rotating substrate at 1-second intervals during the second spin-coating step, 20 seconds before the end of the procedure. The substrate was then immediately annealed on a hot plate at 100°C for 10 minutes, followed by annealing at 65°C for at least 10 minutes. Post-treatment was performed by spin-coating with the material dropped during rotation, and the spin-coating process was carried out at 1333 rpm s -1 The speed was set to 4000 rpm for 20 seconds during acceleration. Following the spin coating, the film was immediately annealed again at 100°C for about 5 minutes.

[0092] Next, the treated film was formed. The control (w / o) was prepared without post-treatment. In the case of the PP (piperazine) treated film, 0.25 mg mL of the mixed solvent was used. -1PP was coated onto the film surface. For PPCPTA-treated films, a solution containing 0.25, 0.50, and 1.0 mg of CPTA (C60 pyrrolidine tris-acid) in 1 mL of mixed solvent was prepared, and then 1 mL of PP solution (0.5 mg mL in mixed solvent) was added. -1 The CPTA solution was individually added to the CPTA solution. Next, the solution was heated at 70°C for approximately 30 minutes with vigorous stirring. These three solutions, prepared by increasing the amount of CPTA, are shown as PPCPTA-C1, PPCPTA-C2, and PPCPTA-C3, respectively. All solutions were cooled to room temperature, filtered, and then coated onto the film surface. SEM images of the films prepared with and without treatment are shown in Figure 22. The scale bar in the top view of Figure 22 is 1 μm. Figure 22 shows the distribution of device parameters obtained by forward and reverse JV scanning of untreated (control), PP, PPCPTA-C1, PPCPTA-C1, PPCPTA-C2, and PPCPTA-C3. Six samples were used for each condition. Table 6 shows the dispersion of device parameters by forward and reverse JV scanning of control (w / o), PP, PPCPTA-C1, PPCPTA-C1, PPCPTA-C2, and PPCPTA-C3.

[0093] [Table 6] [Industrial applicability]

[0094] This invention can be used in fields such as solar cells and organic LEDs.

Claims

1. The process of preparing the perovskite precursor solution, The process includes the step of forming a perovskite layer using the perovskite precursor liquid. A method for producing a perovskite layer, The aforementioned perovskite layer is Compounds having a perovskite structure represented by the following formula (I) AM ｍ X ｎ ・・・(I) (In formula (I), A contains any one or more of methylammonium cation (CH ３ NH ３ ＋ ), formamidinium cation (NH ２ CHNH ２ ＋ ), and cesium cation (Cs ＋ ), and M is Pb ２＋ and Sn ２＋ A metal ion containing either or both of the following: X is F － , Cl － , Br － , and I － It is one or more of the following types: m is between 0.8 and 1.

2. n is between 2.8 and 3.2.) Glycine derivatives represented by the following formula (II) 【Chemistry 1】 (In formula (II), R １ is, C １ ~C ５ Alkylene group, C ６ ~C １０ Arylene group, formula -C(=NH)NHCH ２ A group indicated by -, or -R ３ R ４ The group indicated by - is shown. R ２ This represents a carbon atom, P(OH), or S(=O), R ３ and R ４ teeth, R ３ However, C １ ~C ５ It shows an alkylene group, R ４ C ６ ~C １０ Does it show an arylene group? R ３ However, C ６ ~C １０ It shows an arylene group, R ４ C １ ~C ５ (Indicates an alkylene group.) A method for producing a perovskite layer, comprising a salt of the glycine derivative.

2. A method for producing a perovskite layer according to claim 1, The step of forming a perovskite layer using the perovskite precursor liquid is as follows: A method for producing a perovskite layer, comprising applying the perovskite precursor solution and then applying a reverse solvent to move the glycine derivative represented by formula (II) or a salt thereof to the interface side of the perovskite layer.

3. A method for manufacturing a laminate, comprising the steps of forming a perovskite layer by the method for manufacturing a perovskite layer described in claim 2, and applying a surface treatment solution containing an amine or a salt thereof to the perovskite layer to form a surface treatment layer.

4. A method for manufacturing a laminate according to claim 3, The aforementioned surface treatment solution contains an amine and an acid, and is a method for producing a laminate.

5. A method for manufacturing a laminate according to claim 3, The method for manufacturing a laminate further comprises a surface treatment liquid containing toluene.

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