KR102234701B1 - Perovskite Ink for Printing and the Printing Method Using Thereof - Google Patents

Abstract

The present invention relates to a perovskite ink having a high viscosity and, more specifically, to a perovskite ink comprising: a perovskite compound including amidinium-based ions, organic ammonium ions, or amidinium-based ions and organic ammonium ions as monovalent cations, and metal ions and halogen anions; a pyrolytic thickener; and a solvent.

Description

Perovskite Ink for Printing and the Printing Method Using Thereof}

The present invention relates to a perovskite ink for printing and a printing method using the same, and more particularly, to a perovskite ink having a high viscosity without deterioration of the physical properties of the perovskite compound, and a printing method using the same. .

An organometallic halide with a perovskite structure referred to as an organic-inorganic perovskite compound, consisting of an organic cation (A), a metal cation (M), and a halogen anion (X), and is represented by the formula of _{AMX 3} to be.

Currently, perovskite solar cells using organic-inorganic perovskite compounds as light absorbers are the closest to commercialization among next-generation solar cells including dye-sensitized and organic solar cells, and an efficiency of up to 20% is reported. No. 2014-0035284), and interest is increasing more and more.

These perovskite solar cells have an efficiency comparable to that of silicon solar cells, have a very low material cost, can be manufactured by a low-temperature process, and are determined by a solution process in which an organic-inorganic perovskite compound solution is simply applied. It is possible to manufacture a film and has excellent commerciality.

In order for perovskite solar cells to be commercialized, technology development that can mass-produce high-quality solar cells with low-cost and simple processes must be made with improved device stability.

In the case of forming a perovskite compound film through printing which is advantageous for mass production, the ink used must have a viscosity of a certain or higher so that the printing aptitude can be satisfied. However, there is a limit to the amount of the organic-inorganic perovskite compound dissolved in the solvent, and there is a limit to the change of the solvent as the solvent must have favorable volatility to form a uniform film by spontaneous crystallization. -The solution process, which is the biggest commercial advantage of inorganic perovskite compounds, is acting as a disadvantage.

In addition, when a thickener such as polymer or cellulose is used to increase the viscosity of the organic-inorganic perovskite compound solution, there is a problem that the film quality of the organic-inorganic perovskite compound film is greatly degraded by the thickener.

Therefore, in order to mass-produce perovskite solar cells through a simple printing process, first of all, a perovskite compound film having a low surface roughness and a uniform thickness is formed without adversely affecting the film quality of the perovskite compound. There is a need to develop a perovskite ink having a high viscosity while using a solvent that is advantageous for the same.

Republic of Korea Patent Publication No. 2014-0035284

It is an object of the present invention to provide a perovskite ink suitable for a printing process including gravure printing, having a high viscosity while preventing film quality degradation of an organic-inorganic perovskite compound film.

The perovskite ink according to the present invention is a printing ink, and a perovskite containing amidinium-based ions, organic ammonium ions, or amidinium-based ions and organic ammonium ions as monovalent cations, and containing metal ions and halogen anions. Skyt compounds; Pyrolytic thickeners; And a solvent;

In the perovskite ink according to an embodiment of the present invention, the thermally decomposable thickener may be an ammonium compound.

The perovskite ink according to an embodiment of the present invention may be for gravure printing.

In the perovskite ink according to an embodiment of the present invention, the viscosity of the perovskite ink may be 15 cPs or more based on 25°C.

In the perovskite ink according to an embodiment of the present invention, the thermally decomposable thickener may be decomposed and removed at a temperature of 200° C. or less.

In the perovskite ink according to an embodiment of the present invention, the thermally decomposable thickener may be methyl ammonium chloride.

The perovskite ink according to an embodiment of the present invention may contain a perovskite compound having a concentration of 2.0 to 3.5M.

In the perovskite ink according to an embodiment of the present invention, the molar ratio of the perovskite compound to the thermally decomposable thickener contained in the perovskite ink may be 1:0.3 to 1.0.

The present invention includes a printing method using the above-described perovskite ink.

The printing method of the perovskite compound according to the present invention includes the step of gravure printing the above-described perovskite ink.

A printing method of a perovskite compound according to an embodiment of the present invention comprises the steps of gravure printing the perovskite ink on a substrate to prepare a printed material; And removing the thermally decomposable thickener by heat-treating the printed matter at a temperature equal to or higher than the thermal decomposition temperature of the thermally decomposable thickener.

The perovskite ink according to an embodiment of the present invention contains amidium-based ions and organic ammonium ions as monovalent cations, and a perovskite compound containing metal ions and halogen anions, and a thermally decomposable thickener. , It has the advantage of having a high viscosity of 15 cPs or more without using a thickener such as polymer or cellulose, and the thermally decomposable thickener can be easily removed at low temperature after printing the ink, so that the film quality of the perovskite compound film is fundamentally reduced. There is an advantage to be prevented.

In addition, the perovskite ink according to an embodiment of the present invention has a high viscosity of 15 cPs or more, and has the advantage of printing a perovskite compound film through gravure printing suitable for mass production. There is an advantage of being able to form a perovskite compound film in a shape.

1 is an optical photograph of observing the printing pattern of the perovskite compound prepared in Example,
FIG. 2 is an optical photograph of observing the printing pattern of the perovskite compound prepared in Comparative Example,
3 is a scanning electron microscope photograph of a surface of a printed pattern of a perovskite compound prepared in Example.

Hereinafter, with reference to the accompanying drawings, the printing perovskite ink of the present invention and a printing method using the same will be described in detail. The drawings introduced below are provided as examples in order to sufficiently convey the spirit of the present invention to those skilled in the art. Accordingly, the present invention is not limited to the drawings presented below and may be embodied in other forms, and the drawings presented below may be exaggerated to clarify the spirit of the present invention. At this time, unless there are other definitions in the technical terms and scientific terms used, they have the meanings commonly understood by those of ordinary skill in the technical field to which the present invention belongs, and the gist of the present invention in the following description and accompanying drawings Descriptions of known functions and configurations that may be unnecessarily obscure will be omitted.

In the present invention, the perovskite compound (or organic-inorganic perovskite compound) refers to an organometallic halide having a perovskite structure. In an embodiment, the perovskite compound may satisfy the formula of _{AMX 3} based on organic cation (A), metal cation (M), and anion (X). Perovskite compounds are three-dimensional in which A (organic cation) _{combines with 12 X (anions) with AX 12} to form a cubic octahedral structure, and M (metal cation) is MX ₆ with X (anion) and octahedral structure. It may have a structure, but is not necessarily limited thereto.

In the present invention, the perovskite ink is an ink used for printing, and refers to an ink in a state in which a perovskite compound is dissolved in a solvent.

In the present invention, the perovskite solar cell may mean a solar cell containing a perovskite compound as a light absorber.

In the present invention, the thermally decomposable thickener may be decomposed (pyrolyzed) removed at a temperature at which the perovskite compound is not damaged (or decomposed) by heat, and may mean a material that increases the viscosity of the ink.

In the present invention, high viscosity may mean a viscosity that can be printed using a printing method requiring high viscosity, such as gravure printing, screen printing, slot die printing, inkjet printing, and the like. It may mean a viscosity of 15 cPs or more. A viscosity of 15 cPs or more is a viscosity that enables gravure printing of a film having a thickness corresponding to ^{the thickness (10 2 μm order) of a conventional perovskite compound-based light absorbing layer in a designed shape.}

The perovskite ink according to the present invention is a printing perovskite ink, which contains an amidium-based ion, an organic ammonium ion, or an amidium-based ion and an organic ammonium ion as a monovalent cation, and contains metal ions and halogen anions. Containing perovskite compounds; Pyrolytic thickeners; And a solvent;

The perovskite ink according to the present invention contains a thermally decomposable thickener, so that the viscosity of the ink can be improved by the thermally decomposable thickener.

In addition, the perovskite ink according to the present invention does not contain a polymer or a cellulose thickener (additive), and contains a thermally decomposable thickener that is easily decomposed and removed at low temperatures, so that the viscosity of the ink can be increased by printing. There is an advantage in that the film quality of the produced perovskite compound film is prevented from being deteriorated.

As the perovskite ink contains a thermally decomposable thickener that is thermally decomposed at a low temperature, after printing using the perovskite ink is performed, a post-treatment for removing the thermally decomposable thickener from the printed material may be performed.

Perovskite ink can improve the viscosity of the perovskite ink, and selectively among the perovskite compounds and pyrolytic thickeners contained in printed materials, the pyrolytic thickener can be easily removed at a lower temperature. The pyrolytic thickener contained may be an ammonium compound, advantageously a C1-C2 alkylammonium salt, more advantageously a C1-C2 alkylammonium halide. The C1-C2 alkylammonium halide itself acts to dissolve the perovskite compound in the ink beyond the solubility limit with a thickening effect of increasing the viscosity of the ink, so that the ink may have a remarkably high viscosity.

Advantageously, the halogen anion contained in the perovskite compound may be an iodine ion, a bromine ion, or an iodine ion and a bromine ion, and the thermally decomposable thickener is preferably a C1-C2 alkyl ammonium chloride. Chlorine has a greater reactivity than iodine or bromine, does not affect the composition of the perovskite compound contained in printed matter, and can be selectively removed at a lower temperature. The C1-C2 alkyl ammonium chloride is preferably a methyl ammonium chloride. In this case, the pyrolytic thickener is advantageous because it can be decomposed at a lower temperature, and further, all pyrolysis products are removed in a gaseous form, and a residue is not formed on the perovskite compound film, which is advantageous.

The pyrolytic thickener can be decomposed and removed at a temperature of 200° C. or less. That is, the thermal decomposition temperature of the thermally decomposable thickener may be 200°C or less, specifically 150°C or less, more specifically 140°C or less, and even more specifically 120°C or less. Substantially, the pyrolytic thickener can be decomposed and removed at a temperature of 100 to 150°C, more substantially 100 to 140°C, and even more substantially 100 to 120°C.

As described above, the halogen anion contained in the perovskite compound may be an iodine ion, a bromine ion, or an iodine ion and a bromine ion, and the thermally decomposable thickener may be a C1-C2 alkyl ammonium chloride. In this case, the pyrolytic thickener can be decomposed and removed at a temperature of 100 to 150° C., more substantially 100 to 140° C., and even more substantially 100 to 120° C., and can be completely removed without unwanted residues. In addition, thermal damage to the perovskite compound contained in the printed material can be prevented, while the thermally decomposable thickener can be selectively and quickly removed, and the desired perovskite compound composition change can be completely prevented by the thermally decomposable thickener. .

The perovskite ink may contain a perovskite compound at a concentration of 0.8 to 3.5M. As described above, when the thermally decomposable thickener is a C1-C2 alkylammonium halide, the solubility (solubility limit) of the perovskite compound in the same solvent can be increased by adding the thermally decomposable thickener, which is more advantageous for high viscosity. . As is known, the molar concentration of the perovskite compound in a saturated solution based on 25°C of the non-aqueous polar organic solvents that dissolve the perovskite compound is 1.1M to 1.8M. However, according to an advantageous example of the present invention, when the thermally decomposable thickener is a C1-C2 alkylammonium halide, the perovskite ink contains a perovskite compound at a high concentration of 1.8M or more, specifically 2.0M or more. can do. Substantially, when the thermally decomposable thickener is a C1-C2 alkylammonium halide, the perovskite ink may contain the perovskite compound at a concentration of 2.0 to 3.5M, more substantially at a concentration of 2.5 to 3.5M.

In one embodiment, the perovskite compound contained in the perovskite ink: the molar ratio of the thermally decomposable thickener may be 1: 0.3 to 1.0, specifically 1: 0.3 to 0.6, more specifically 1: 0.3 to 0.5 have. The viscosity of the ink can be increased by increasing the content of the thermally decomposable thickener. Furthermore, when the thermally decomposable thickener is a C1-C2 alkylammonium halide, the solubility limit of the perovskite compound is also increased by the thermally decomposable thickener, resulting in thermal decomposition. It is possible to increase the viscosity of the ink by both a sexual thickener and a perovskite compound. When the molar ratio of the thermally decomposable thickener to the perovskite compound satisfies the above range, the molar concentration of the perovskite compound in the perovskite ink may reach 2.0 to 3.5M, substantially 2.5 to 3.5M concentration. .

In one embodiment, the perovskite ink may be an ink for gravure printing. As is known, gravure printing belongs to the intaglio printing method. In gravure printing, ink is applied to a cylindrical or plate-type printing substrate on which an intaglio pattern is formed, and after removing the ink from the convex portion of the printing substrate through a doctor blade, etc., the object to be printed is placed between the press roll and the printing substrate. It is a printing method in which the ink in the concave portion of the printed board is transferred to a printed object by pressing and pressing.

As gravure printing is an intaglio printing technique, it has the advantage of being able to accurately implement (print) the thickness of the designed perovskite compound film, and it is possible to print highly fine or highly complex shapes with precision, and a continuous printing process is possible. And it is very suitable for mass printing.

Among various printing methods, gravure printing is known to use relatively high viscosity ink. However, as described above, since conventional thickeners degrade the film quality of the perovskite compound film, it is difficult to use practically, and the solvent must also have favorable volatility to form a uniform film by spontaneous crystallization, so it is difficult to change the solvent material. , The maximum viscosity of the perovskite compound solution is limited to the viscosity of the saturated solution (1.1M to 1.8M level) in which the organic-inorganic perovskite compound is dissolved up to the solubility limit. The maximum viscosity of the perovskite compound solution (the viscosity of the saturated solution) is only 5 to 8 cPs, so gravure printing is not possible.

However, the perovskite ink according to an embodiment of the present invention may have a viscosity of 15 cPs or more, which is a gravure printable viscosity, and accordingly, the perovskite ink may be an ink for gravure printing. In addition, advantageously, when the thermally decomposable thickener is a C1-C2 alkylammonium halide, the solubility limit of the perovskite compound in the same solvent is increased, and the viscosity of the ink may be 17 cPs or more, and the C1-C2 alkyl ammonium in the ink Depending on the content of the halide and perovskite compound, the viscosity of the ink can be increased up to 100 cPs or more. The viscosity of the perovskite ink substantially for gravure printing may be 15 to 150 cPs, more substantially 17 to 100 cPs, and even more substantially 17 to 50 cPs. At this time, the viscosity of the perovskite compound ink may be a viscosity of 25°C, and may be a value measured using a Brookfield viscometer.

However, the ink of the present invention is limited to gravure printing ink and cannot be interpreted, and as described above, the viscosity of the ink according to an embodiment may reach 100 cPs. Accordingly, the ink of the present invention can be used to form a perovskite compound pattern by using various printing methods such as conventional commercial printing methods requiring high viscosity, specific examples such as screen printing, slot die printing, and inkjet printing.

The perovskite compound of the perovskite ink may satisfy Formula 1.

(Formula 1)

B _1-x A _x MX ₃

In Formula 1, A is a monovalent organic ammonium ion, B is a monovalent amidine ion, M is a divalent metal ion, X is a halogen ion, x is 0≤x≤1, for example, 0.01≤ x≤0.1, as another example, is a real number of 0.02≤x≤0.06.

In Formula 1, the monovalent organic ammonium ion may be R ₁ -NH ₃ ⁺ (R ₁ is C1-C24 alkyl, C3-C20 cycloalkyl or C6-C20 aryl), and the amidinium ion is Formula 2 may be satisfied.

(Formula 2)

In Formula 2, R ₂ to R ₆ are each independently hydrogen, C1-C24 alkyl, C3-C20 cycloalkyl, or C6-C20 aryl. In Formula 4, R ₂ to R ₆ may be appropriately selected according to the use of the perovskite compound. In detail, the size of the unit cell of the perovskite compound is related to the band gap, and the small unit cell size may have a band gap energy suitable for use as a solar cell (for example, at a level of 1.1 to 1.5 V). Accordingly, when considering a band gap energy suitable for use as a solar cell, R ₂ to R ₆ are independently of each other, hydrogen, amino or C1-C24 alkyl, specifically, hydrogen, amino or C1-C7 alkyl, More specifically, it may be hydrogen, amino or methyl, and even more specifically, R ₂ may be hydrogen, amino or methyl, and R ₃ to R ₆ may be hydrogen. As a practical example, the amidinium-based ion is a formamidinium (formamidinium, NH ₂ CH=NH ₂ ⁺ ) ion, acetamidinium (acetamidinium, NH ₂ C(CH ₃ )=NH ₂ ⁺ ) ion or guamidi Nium (Guamidinium, NH ₂ C (NH ₂ ) = NH ₂ ⁺ ) ions may be mentioned, but are not limited thereto. Such an example is an example considering the use of a perovskite compound, that is, as a light absorber of sunlight, design of the wavelength band of light to be absorbed, design of the emission wavelength band when used as a light emitting layer of a light emitting device, When used as a semiconductor device of a transistor, R ₂ to R ₆ may be appropriately selected in consideration of an energy band gap and a threshold voltage.

In Formula 1, M is Cu ²⁺ , Ni ²⁺ , Co ²⁺ , Fe ²⁺ , Mn ²⁺ , Cr ²⁺ , Pd ²⁺ , Cd ²⁺ , Ge ²⁺ , Sn ²⁺ , Pb ²⁺ and It may be one or two or more metal ions selected from ^{Yb 2+.}

According to an advantageous example, in formula 1, X is Br ^- can be ^-, I ^- or Br ^- and I. When X is Br ^- and I ^- , X may be (I _1-x Br _x ) (a real number of 0<x<1, specifically 0.01≦x≦0.15, more specifically 0.01≦x≦0.10).

The solvent of the perovskite ink may be any solvent commonly used to prepare a perovskite compound film having a dense and smooth surface in the conventional solution coating method. However, as described above, the perovskite ink according to an embodiment of the present invention has a viscosity that satisfies printability by increasing the concentration of the pyrolytic thickener or the pyrolytic thickener and the perovskite compound itself. I can have it. Accordingly, it is not necessary to change the solvent used in the conventional perovskite solution to another solvent that is advantageous for increasing viscosity in order to increase the viscosity, and it is difficult to remove volatilization and a high viscosity solvent (3-mer The use of oxypropane nitrile, terpineol, butyl carbitol, 3-methoxypropane nitrile, etc.) is unnecessary. Accordingly, the solvent contained in the perovskite ink is preferably a low-viscosity polar organic solvent capable of inducing crystallization of a uniform and homogeneous perovskite compound even in a large area. The low-viscosity polar organic solvent may be a polar organic solvent having a 25°C reference viscosity of 2.0 cps or less, preferably 1.5 cps or less, and more preferably 1.0 cps or less. As a specific example of the low viscosity polar organic solvent, the solvent is dimethylsulfoxide (DMSO), N-methyl-2-pyrrolidone (NMP), N,N-dimethylformamide ( N,N-Dimethylformamide, DMF), gamma-butyrolactone (GBL), N,N-N,N-dimethylacetamide, or a mixed solvent thereof, but is limited thereto. It is not.

The present invention includes a printing method using the above-described perovskite ink.

The printing method of the perovskite compound according to the present invention includes the step of gravure printing the above-described perovskite ink.

A printing method according to an embodiment comprises the steps of gravure printing the perovskite ink on a substrate to produce a printed product; And removing the thermally decomposable thickener by heat-treating the printed matter at a temperature equal to or higher than the thermal decomposition temperature of the thermally decomposable thickener.

The substrate is the object to be printed, and a suitable substrate may be used depending on the intended use of the perovskite compound film, and the substrate is located under the perovskite compound film in consideration of the specific structure of the desired article (device). Of course, the elements may be a pre-formed substrate. In addition, the printing substrate during gravure printing may have an appropriate intaglio pattern formed so that perovskite ink can be printed in a designed position, a designed shape, and a designed thickness in consideration of the specific structure of the desired article (device). Of course.

As an example of a perovskite solar cell, the substrate may include a transparent substrate, a first electrode positioned on the transparent substrate, and a first charge carrier positioned on the first electrode. At this time, the first electrode and the first charge transfer body may be sequentially positioned in a designed shape in the designed area of the transparent material, as well as two or more units in which the first electrode and the first charge transfer body are stacked on the transparent material. Of course, the units can be arranged spaced apart from each other. In the case of gravure printing, the cylindrical or plate-type printed substrate may be formed with an intaglio pattern for transferring perovskite ink in a shape and size corresponding to the first charge transfer body on the top of the first charge transfer body included in the substrate. In this case, it goes without saying that the height of the perovskite ink transferred to the substrate may be controlled by adjusting the depth of the intaglio pattern.

After gravure printing a perovskite ink on a substrate to prepare a printed product, a step of removing the pyrolytic thickener may be performed by heat treating the produced printed product at a temperature equal to or higher than the pyrolysis temperature of the pyrolytic thickener. In this case, the printed material refers to a perovskite ink (hereinafter, collectively referred to as a perovskite ink pattern) transferred to the substrate by the substrate and the intaglio pattern.

At this time, the solvent of the perovskite ink pattern may be volatilized and removed by spontaneous volatilization before the thickener removal step. Unlike this, in the thickener removal step, the volatilization of the solvent and the thermally decomposable thickener may be simultaneously removed. In addition, if necessary, a drying step of volatilizing and removing the solvent from the perovskite ink pattern after gravure printing and before removing the thickener may be further performed. The drying step may be performed at 60 to 100° C., in a specific example, at 60 to 90° C., but is not limited thereto.

The step of removing the thickener is a step of removing the thermally decomposable thickener from the perovskite ink pattern of the printed material, and may be a step of heat-treating the printed product at a temperature equal to or higher than the thermal decomposition temperature of the thermally decomposable thickener. In detail, the heat treatment for removing the thermally decomposable thickener may be performed at a temperature of 120 to 200°C, specifically 120 to 150°C, and more specifically 120 to 140°C. At this time, when the thermally decomposable thickener is methyl ammonium chloride, it is more advantageous because it can be easily removed at a very low temperature of 140°C or less. The heat treatment for removing the pyrolytic thickener may be performed in an air atmosphere, and the heat treatment time may be a time in which the pyrolytic thickener can be sufficiently removed.

(Example 1)

In a mixed solvent of dimethylformamide (DMF) and dimethyl sulfoxide (DMSO) (DMF:DMSO = 8:1 v/v) (FAPbI ₃ ) _1-z (MAPbBr ₃ ) _z (FA=formamidinium, MA=methylammonium, z =0.05) with FAPbI ₃ MAPbBr _{3 was added, and CH 3} NH ₃ Cl, a thermally decomposable thickener, was added to prepare a perovskite ink. At this time, in the perovskite ink, (FAPbI ₃ ) _1-z (MAPbBr ₃ ) _z was a 3M concentration, and _{the molar ratio of the perovskite compound: CH 3} NH ₃ Cl was 7: 3, and the prepared ink was 25° C. The viscosity was 17.6 cPs.

Prints were produced by printing perovskite ink on a polyethylene terephthalate (PET) substrate coated with ITO at a speed of 18 m/min using a ^{table-top gravure printer and a metal plate with an intaglio pattern with a linear density of 120 lines cm -2.} I did.

Thereafter, the prepared printed matter was heat-treated in air at 120° C. for 20 minutes to decompose and remove the thermally decomposable thickener to prepare a printed pattern made of a perovskite compound (thickness: 0.5 μm).

(Comparative Example 1)

In a mixed solvent of dimethylformamide (DMF) and dimethyl sulfoxide (DMSO) (DMF:DMSO = 8:1 v/v) (FAPbI ₃ ) _1-z (MAPbBr ₃ ) _z (FA=formamidinium, MA=methylammonium, z =0.05) with FAPbI ₃ MAPbBr ₃ was added, but was added to the solubility limit to prepare a saturated solution of perovskite with a concentration of _{(FAPbI 3} ) _1-z (MAPbBr ₃ ) _{z of 1.4M.} The viscosity of the prepared saturated perovskite solution at 25°C was 7.5 cPs.

Thereafter, gravure printing was performed in the same manner as in Example 1 using the prepared saturated perovskite solution, and then heat treated in the same manner as in Example 1 to prepare a printed pattern made of a perovskite compound.

1 is an optical picture of observing the printing pattern prepared in Example 1, and FIG. 2 is an optical picture of observing the printing pattern prepared in Comparative Example 1.

As can be seen from FIG. 2, even if the perovskite compound solution used in the conventional solution coating method increases the viscosity as possible by making a saturated state, the pattern is crushed and tailing occurs severely, so that gravure printing is impossible. Able to know. On the other hand, looking at the printed pattern prepared in Example 1, it was confirmed that fine patterns to be implemented through gravure printing were elaborately transferred to the substrate and formed.

In addition, as a result of analysis using X-ray diffraction and X-ray spectroscopy, the prepared printed pattern is selectively removed with a thermally decomposable thickener, and substantially pure (FAPbI ₃ ) _1-z (MAPbBr ₃ ) _z (FA=formamidinium, MA=methylammonium, z=0.05).

3 is a scanning electron microscope photograph of the surface of the printed pattern prepared in Example 1, that is, the surface of the printed pattern made of a perovskite compound after the thermally decomposable thickener was removed. As can be seen from FIG. 3, it was confirmed that the crystal grains of the perovskite compound were uniformly and densely formed, and a clean surface was formed without remaining by-products due to the thickener.

As described above, in the present invention, specific matters and limited embodiments and drawings have been described, but this is provided only to help a more general understanding of the present invention, and the present invention is not limited to the above embodiments, and the present invention is Those of ordinary skill in the relevant field can make various modifications and variations from these descriptions.

Therefore, the spirit of the present invention is limited to the described embodiments and should not be defined, and all things that are equivalent or equivalent to the claims as well as the claims to be described later fall within the scope of the spirit of the present invention. .

Claims (10)

A perovskite ink for printing, the ink is a perovskite compound containing an amidium ion, an organic ammonium ion or an amidium ion and an organic ammonium ion as a monovalent cation, and a metal ion and a halogen anion ; A pyrolytic thickener which is a C1-C2 alkyl ammonium halide; And a solvent; wherein the ink is a printing perovskite ink containing the perovskite compound at a concentration of 2.0 to 3.5M.
delete The method of claim 1,
The printing is a gravure printing perovskite ink. The method of claim 3,
The perovskite ink has a viscosity of 15 cPs or more based on 25°C. The method of claim 1,
The pyrolytic thickener is a perovskite ink that is decomposed and removed at a temperature of 200°C or less. delete delete The method of claim 1,
The perovskite compound contained in the perovskite ink: the molar ratio of the thermally decomposable thickener is 1: 0.3 to 1.0 perovskite ink. A method of printing a perovskite compound comprising the step of gravure printing the perovskite ink according to any one of claims 1, 3 to 5, and 8. The method of claim 9,
Gravure printing the perovskite ink on a substrate to produce a printed product; And
Heat-treating the printed matter at a temperature equal to or higher than the pyrolysis temperature of the pyrolytic thickener to remove the pyrolytic thickener;
Printing method of a perovskite compound comprising a.

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