One-dimensional perovskite capping thin film, manufacturing method thereof, and perovskite solar cell comprising same

Abstract

The present invention relates to a one-dimensional perovskite capping thin film, a method for manufacturing the same, and a perovskite solar cell comprising the same, wherein the one-dimensional perovskite capping layer is formed on a three-dimensional perovskite layer, and the one-dimensional perovskite capping layer is characterized by a dominant facet peak in an XRD pattern, a method for manufacturing the same, and a perovskite solar cell comprising the same.

Description

Technology Field

[0001] The present disclosure relates to a one-dimensional perovskite capping thin film according to embodiments of the present disclosure, a method for manufacturing the same, and a perovskite solar cell comprising the same.

[0002] The present invention was carried out through the InnoCORE project of the Korea Advanced Institute of Science and Technology (KAIST) supported by the Ministry of Science and ICT (1.250021.01) and the research project of Ulsan National Institute of Science and Technology (UNIST) (1.250008.01). Background Technology

[0003] Perovskite solar cells (PeSCs) are attracting attention as a promising candidate for next-generation photovoltaic power generation technology, and have recently achieved a power conversion efficiency (PCE) of approximately 27.0%. Based on excellent physical properties such as a high light absorption coefficient, direct bandgap, long carrier diffusion length, and bandgap tunability, PeSCs are approaching the performance of conventional silicon solar cells.

[0004] As a strategy to improve the efficiency and stability of perovskite solar cells, the introduction of low-dimensional (2D, 1D, 0D) perovskites as capping layers on top of three-dimensional (3D) perovskite layers is being actively researched. These low-dimensional perovskites (LDPs) contribute to improving the long-term stability of the device by effectively passivating surface defects, forming built-in potentials, and blocking the penetration of moisture and oxygen. Conventional LDP capping layers have a problem in that they obstruct charge transport pathways due to random crystal orientation and energy level mismatch in pinned perovskite solar cells. To address this, various LDP formation control technologies are being developed. For example, a 3D / MPA / 2D heterojunction structure using a thin film of 4-methoxyphenylphosphonic acid (MPA) as a passivating dipole layer between a 3D absorber and a 2D capping perovskite, or the formation of a vertically oriented 2D perovskite through vacuum deposition has been reported.

[0005] Meanwhile, one-dimensional (1D) perovskites are based on a lead-halide octahedral structure aligned along a single crystal axis and are surrounded by bulky organic cations, suggesting potential as interface modifiers. These 1D structures can improve device stability through surface defect healing, inhibition of ion migration, and hydrophobic properties. Nevertheless, compared to 2D perovskites, the application of capping layers in pin-structured PeSCs of 1D perovskites is relatively understudied. The problem to be solved

[0006] One-dimensional (1D) perovskite capping layers present a promising method for improving the efficiency and stability of perovskite solar cells (PeSC), but there is a lack of device improvement effects and related research in reverse perovskite solar cells.

[0007] The present invention aims to solve the aforementioned problems by providing a one-dimensional perovskite capping thin film, which is a cross-sectionally adjustable one-dimensional perovskite capping layer for high-efficiency and high-stability perovskite solar cells.

[0008] The present invention provides a perovskite solar cell comprising a one-dimensional perovskite capping thin film according to embodiments of the present invention.

[0009] The present invention provides a method for manufacturing a one-dimensional perovskite capping thin film, wherein a cross-sectional controllable one-dimensional perovskite capping layer is formed using a simple solution process.

[0010] However, the problems that the present invention aims to solve are not limited to those mentioned above, and other unmentioned problems will be clearly understood by those skilled in the art from the description below. means of solving the problem

[0011] According to one embodiment, the one-dimensional perovskite capping film of the present invention is a one-dimensional perovskite capping layer formed on a three-dimensional perovskite layer, and the one-dimensional perovskite capping layer may have a facet peak dominant in the XRD pattern.

[0012] According to one embodiment, the capping layer may comprise a perovskite compound represented by ABX3, wherein A is a cation derived from the following chemical formula 1, B is lead (Pb), and X is an anion selected from halogens.

[0013] [Chemical Formula 1]

[0014]

[0015] (R1, R2, and R3 are each selected from hydrogen, C1 to C10 alkyl groups, C2 to C10 alkenyl groups, benzyl groups, and aryl groups, and X' is a halogen, NO3 - and H3CSO3 - (Selected from.)

[0016] According to one embodiment, the capping layer may comprise at least one perovskite compound selected from [Edimim(1-ethyl-2,3-dimentylimidazolium)]-PbX3, [BMIM(1-butyl-3-methylimidazolium ion)]-PbX3, [EMIM(1-ethyl-3-methylimidazolium)]-PbX3, [VMIM(1-vinyl-3-methylimidazolium)]-PbX3, [DMIM(1,3-dimethylimidazolium)]-PbX3, and [BzMIM(1-benzyl-3-methylimidazolium)]-PbX3.

[0017] According to one embodiment, the one-dimensional perovskite capping layer may be formed by depositing and heat treating a precursor solution comprising a compound represented by Formula 1; and at least one organic solvent among a hydrocarbon solvent, a carbon chloride solvent, and an ether solvent having a dielectric constant of 8 or less and a dipole moment of 2 or less or both.

[0018] According to one embodiment, the solvent may comprise at least one of pentane, hexane, benzene, heptane, toluene, 1,4-dioxane, diethyl ether, tetrahydrofuran (THF), and chloroform.

[0019] According to one embodiment, the cross-section may be a (200) plane and a (102) plane, and may be a (200) plane enhanced one-dimensional perovskite in which the peak intensity of the XRD pattern of the (200) plane is higher than that of the (102) plane.

[0020] According to one embodiment, the one-dimensional perovskite capping layer may have a peak intensity ratio of the cross-section according to the following formula greater than 0.5.

[0021] [Equation 1]

[0022] Peak intensity ratio = I 200 / I 102

[0023] (I is the intensity value of each peak in the XRD pattern.)

[0024] According to one embodiment, the peak ratio of the cross-section may be 0.7 or higher.

[0025] According to one embodiment, the one-dimensional perovskite capping layer may comprise the same divalent metal as the perovskite layer.

[0026] According to one embodiment, a method for manufacturing a one-dimensional perovskite capping thin film of the present invention may comprise: a step of preparing a three-dimensional perovskite layer; a step of forming a precursor film by depositing a precursor solution comprising the following chemical formula 1 and an organic solvent on the three-dimensional perovskite layer; and a step of heat-treating the precursor film.

[0027] According to one embodiment, the heat treatment step may be performed at 80°C to 150°C for at least 1 minute.

[0028] According to one embodiment, the precursor solution may comprise a compound represented by Formula 1; and at least one organic solvent among a hydrocarbon solvent, a carbon chloride solvent, and an ether solvent having a dielectric constant of 8 or less and a dipole moment of 2 or less or both.

[0029] According to one embodiment, the solvent may comprise at least one of pentane, hexane, benzene, heptane, toluene, 1,4-dioxane, diethyl ether, tetrahydrofuran (THF), and chloroform.

[0030] A perovskite solar cell of the present invention according to one embodiment comprises: a first electrode layer; a hole transport layer on the electrode layer; a perovskite-based photoactive layer on the hole transport layer; a one-dimensional perovskite capping layer on the photoactive layer; an electron transport layer on the capping layer; and a second electrode on the electron transport layer; wherein the one-dimensional perovskite capping layer may be a one-dimensional perovskite capping thin film of claim 1.

[0031] According to one embodiment, the thickness of the capping layer may be 1 nm or more.

[0032] According to one embodiment, an organic buffer layer may be further included between the electron transport layer and the second electrode.

[0033] A method for manufacturing a perovskite solar cell according to one embodiment of the present invention comprises: a step of forming a perovskite-based photoactive layer on a hole transport layer; a step of forming a precursor film by depositing a precursor solution comprising the following chemical formula 1 and an organic solvent on the perovskite-based photoactive layer; and a step of heat-treating the precursor film.

[0034] It may include.

[0035] According to one embodiment, the step of forming the photoactive layer may be to heat treat at 80°C to 150°C for 30 minutes or more after depositing a three-dimensional perovskite precursor.

[0036] According to one embodiment, the step of heat-treating the precursor film may be to heat-treat at 80°C to 150°C for at least 1 minute. Effects of the invention

[0037] According to one embodiment, the present invention can increase photoelectric efficiency by improving electron extraction through enhancing the perovskite Fermi level by controlling the cross-section of a one-dimensional perovskite, and can improve moisture stability by applying a thermodynamically stable one-dimensional perovskite capping layer and the same to a solar cell (e.g., an inverted solar cell). Brief explanation of the drawing

[0038] FIG. 1 is a schematic diagram showing a cross-sectional control process of a one-dimensional perovskite according to a treatment solvent of the present invention according to one embodiment. FIG. 2 illustrates, in an exemplary manner, the configuration of a perovskite solar cell of the present invention according to one embodiment. FIG. 3 illustrates, in an exemplary manner, the configuration of a perovskite solar cell of the present invention according to one embodiment. FIG. 4 is a schematic diagram showing the shape deformation of a one-dimensional perovskite controlled by the dissociation constant (ξ) of an ionic liquid (IL) in an embodiment of the present invention, according to one embodiment. Figure 5 shows an experimental process for controlling the morphology and dominant cross-section of a one-dimensional perovskite through solvent control in an embodiment of the present invention according to one embodiment, and an X-ray pattern of a perovskite film (i.e., EMIMPbI3) treated with EMIM-I dissolved in IPA and THF, respectively. Figure 6 shows the difference in electron density (below) according to the cross-section (top) of a one-dimensional perovskite (EMIMPbI3) in an embodiment of the present invention, according to one embodiment. Figure 7 shows the difference in electron transport according to the cross-sectional control of a one-dimensional perovskite (EMIMPbI3) in an embodiment of the present invention, according to one embodiment. FIG. 8 illustrates, according to one embodiment, PbI2, PbI2+EMIM-I, PbI2+EMIM-I+IPA (IPA), and PbI2+EMIM-I+THF (THF) in an embodiment of the present invention. 207 This shows the Pb NMR spectrum. FIG. 9 shows the UPS spectrum of an EMIM-I treated perovskite film in an embodiment of the present invention according to one embodiment. FIG. 10 shows an energy level diagram of a 3D perovskite / 1D EMIMPbI3 heterostructure in an embodiment of the present invention according to one embodiment. FIG. 11 shows the measurement results of the JV characteristics of PeSC in an embodiment of the present invention according to one embodiment. Figure 12 shows SEM images of perovskite films after treatment with EMIM-I dissolved in IPA and THF, respectively, in an embodiment of the present invention, according to one embodiment. FIG. 13 shows KPFM images of perovskite films after treatment with EMIM-I dissolved in IPA and THF, respectively, in an embodiment of the present invention, according to one embodiment. FIG. 14 shows the TPC measurement results of PeSCs in an embodiment of the present invention according to one embodiment. FIG. 15 shows the stability of PeSC (ambient temperature and humidity without encapsulation) in ISOS-D1 (ambient temperature and humidity) in an embodiment of the present invention, evaluated via PCE in the case without EMIM-I treatment (control group) and in the case with EMIM-I treatment, according to one embodiment. According to one embodiment, FIG. 16 shows the change in the XRD pattern of a perovskite film treated with EMIM-I(THF) in an embodiment of the present invention over 96 hours in ambient air (50-60 RH%). Figure 17 shows the JV curve of PeSC according to the concentration of EMIM-I dissolved in THF in an embodiment of the present invention, according to one embodiment. Specific details for implementing the invention

[0039] Embodiments of the present invention will be described in detail below with reference to the attached drawings. In describing the present invention, specific descriptions of related known functions or configurations will be omitted if it is determined that such detailed descriptions may unnecessarily obscure the essence of the present invention. Furthermore, terms used in this specification are used to appropriately express preferred embodiments of the present invention, and these may vary depending on the intent of the user or operator, or the conventions of the field to which the present invention belongs. Accordingly, the definitions of these terms should be based on the content throughout this specification. Identical reference numerals in each drawing indicate identical components.

[0040] Throughout the specification, when it is stated that a component is located "on" another component, this includes not only cases where a component is in contact with another component, but also cases where another component exists between the two components.

[0041] Throughout the specification, when a part is described as "including" a certain component, this means that it does not exclude other components but may include additional components.

[0042] In this document, each of the phrases such as “A or B,” “at least one of A and B,” “at least one of A or B,” “A, B or C,” “at least one of A, B and C,” and “at least one of A, B, or C” may include any one of the items listed together in the corresponding phrase, or all possible combinations thereof. Terms such as “first,” “second,” or “first” or “second” may be used simply to distinguish a component from another component and do not limit the components in any other aspect (e.g., importance or order).

[0043] Hereinafter, the one-dimensional perovskite capping thin film of the present invention, the method for manufacturing the same, and the perovskite solar cell including the same will be described in detail with reference to the embodiments and drawings. However, the present invention is not limited to these embodiments and drawings.

[0044] According to one embodiment, the one-dimensional perovskite capping film of the present invention is a one-dimensional perovskite capping layer formed on a three-dimensional perovskite layer, wherein the capping layer is formed by treating a three-dimensional (3D) perovskite layer with a precursor solution containing a one-dimensional perovskite forming material and a solvent, and may include a one-dimensional (1D) perovskite compound formed by reacting the precursor solution with an excess metal (e.g., a divalent metal) (e.g., lead (Pb)) of the three-dimensional perovskite layer. The one-dimensional perovskite forming material is an ionic material having a large organic cation represented by the following chemical formula 1, and various one-dimensional perovskites can be formed by changing the cation and anion. For example, a one-dimensional perovskite compound having a composition represented by ABX3 can be formed by applying the compound of chemical formula 1. In the above ABX3, A is a cation derived from an imidazolium ionic liquid, which is a compound represented by the following chemical formula 1, B is a divalent metal, and X may be an anion.

[0045] [Chemical Formula 1]

[0046]

[0047] According to one embodiment, in Formula 1, R1, R2, and R3 are each selected from hydrogen, an alkyl group, an alkenyl group, a benzyl group, and an aryl group, and A may be an anion. The alkyl group may be an alkyl group having 1 to 10 carbon atoms; 1 to 8 carbon atoms; 1 to 6 carbon atoms; 1 to 5 carbon atoms; 1 to 4 carbon atoms; 1 to 3 carbon atoms; or 1 to 2 carbon atoms. The alkenyl group may be an alkenyl group having 2 to 10 carbon atoms; 2 to 8 carbon atoms; 2 to 6 carbon atoms; 2 to 5 carbon atoms; 2 to 4 carbon atoms; or 2 to 3 carbon atoms. The aryl group may be an alkenyl group having 6 to 12 carbon atoms; or 6 to 10 carbon atoms. Alternatively, it may be an aryl group having 6 carbon atoms. The above X' is a halogen (I, Cl, Br, F) anion, NO3 - , H3CSO3 - It may be selected from the following. For example, the compound of Formula 1 above may be Edimim(1-ethyl-2,3-dimentylimidazolium)-X', BMIM(1-butyl-3-methylimidazolium ion)-X', EMIM(1-ethyl-3-methylimidazolium)-X', VMIM(1-vinyl-3-methylimidazolium)-X', DMIM(1,3-dimethylimidazolium)-X' It may include at least one of BzMIM(1-benzyl-3-methylimidazolium)-X'.

[0048] According to one embodiment, B may be Pb, Sn, Ge, Ga, In, Al, Sb, Bi, or Po. X may be an anion selected from halogens (I, Cl, Br, F). According to one embodiment, the capping layer may comprise a one-dimensional perovskite compound having at least one composition among [Edimim(1-ethyl-2,3-dimentylimidazolium)]-BX3, [BMIM(1-butyl-3-methylimidazolium ion)]-BX3, [EMIM(1-ethyl-3-methylimidazolium)]-BX3, [VMIM(1-vinyl-3-methylimidazolium)]-BX3, [DMIM(1,3-dimethylimidazolium)]-BX3, and [BzMIM(1-benzyl-3-methylimidazolium)]-BX3. Here, B and X are as mentioned above, and preferably may be Pb and I.

[0049] According to one embodiment, the one-dimensional perovskite capping thin film may be formed on a three-dimensional perovskite layer to form a heterojunction of one-dimensional and three-dimensional perovskites. The one-dimensional perovskite capping layer may comprise a perovskite compound having the same or different composition as the three-dimensional perovskite layer. Additionally, the one-dimensional perovskite capping layer may comprise a divalent metal identical to that of the perovskite layer. The three-dimensional perovskite may be applied without limitation as long as it is a three-dimensional perovskite represented by ABX3, A2BX4, ABX4, APbX3, etc. Here, A is an organic ammonium (RNH3) + , organic amidinium derivative (RC(=NR2)NR2) + , organoguanidinium derivative (R2NC(=NR2)NR2) + , organic diammonium , formamidinium (FA; CH(NH2)2 +Selected from ), etc. (R can be selected from cyclic, aromatic, or linear hydrocarbons), and X is F - , Cl - , Br - , I - , At - B is selected from divalent metals (e.g., transition metals, post-transition metals, rare earth metals, alkaline earth metals, etc.). For example, FA 1-x Cs x PbI 3, MASnBrI2, MASnBrCl 2, MASnBr3, FAPbI3, (FAPbI3) 1-x , (MAPbBr3) x , CsPbI2Br, CsPbI3, CsPbBr3, Cs 0.05 (FA 1-x MA x ) 0.95 Pb(I 1-y Br y )3, MA x FA 1-x PbI3, GAPbI3, GA x MA 1-x PbI3, (PEA)2(MA)2Pb3I 10 , (IC2H4NH3)2(MA) n-1 PbI 3n+1 , MASn x Pb 1-x I3, MAPbI 3-x Cl x , FAPb(Br y I 1-y )3, FA y Cs 1-y Pb[I (1-x) Br x ]3, CsPbIBr2, Cs2PbI6, CsPb 1-x SrxI2Br, CsPb 0.9 Sn 0.1It may include at least one of IBr2. Here, FA (formamidinium), MA (methylammonium), GA (guanidinium), and PEA (phenylethylammonium).

[0050] According to one embodiment, with reference to FIG. 4, by changing the anion of Formula 1 in the precursor solution, a one-dimensional perovskite in which facet peaks are dominant in the XRD pattern can be formed, and furthermore, the shape of the one-dimensional perovskite, such as rod-shaped or planar-shaped, can be controlled. In addition, by changing the solvent in the precursor solution, the facet ratio of the one-dimensional perovskite in the XRD pattern can be changed through solvent control. For example, with reference to FIG. 1, a one-dimensional perovskite in which (n-type) facets (e.g., (200) planes) with high electron density are enhanced can be formed.

[0051] According to one embodiment, the precursor solution may control the cross-section by applying a compound represented by Formula 1 and an organic solvent that is low polarity or nonpolar. That is, device performance can be improved by controlling the ratio of cross-section peaks in the XRD pattern. For example, the organic solvent may include at least one of a hydrocarbon solvent, a carbon chloride solvent, and an ether solvent having a dielectric constant of 8 or less; 7 or less; 5 or less; 3 or less; or 2 or less; and a dipole moment of 2 or less; 1.8 or less; 1.7 or less; 1.5 or less; 1.3 or less; 1.0 or less; 0.5 or less; or about 0; or both. For example, the solvent may include at least one of pentane, hexane, benzene, heptane, toluene, 1,4-dioxane, diethyl ether, tetrahydrofuran (THF), and chloroform.

[0052] According to one embodiment, the precursor solution can improve device performance by controlling the end-face of the one-dimensional perovskite using a low-polarity solvent (e.g., tetrahydrofuran). This allows for the control of the morphology, surface end, and optoelectronic performance of the one-dimensional perovskite thin film by controlling the dissociation of the ionic liquid (IL) represented by Formula 1 using the solvent. That is, the low-dissociation IL and strong Pb 2+By introducing an anti-dissociation IL combined with a coordination solvent, this solvent can control the Pb site so that the anti-dissociation IL can mimic the effect of a high-dissociation IL. This can form a 1D perovskite with a dominant (200) plane orientation while maintaining long-term stability, realize an optimized 1D / 3D heterojunction PeSC, and improve power conversion efficiency. In addition, it can realize a durable and high-performance solar cell.

[0053] According to one embodiment, the cross-sectional planes are a (200) plane and a (102) plane. Referring to FIGS. 5 and 6, the (200) plane is a high electron density surface exhibiting superior performance compared to the (102) plane, which can provide excellent charge transport and interfacial contact. A (200) plane-enhanced one-dimensional perovskite can be formed in which the peak intensity of the XRD pattern of the (200) plane is higher than that of the (102) plane. For example, the one-dimensional perovskite capping layer according to the following Equation 1 The peak ratio of the longitudinal section may be greater than 0.5; 0.6 or more; 0.7 or more; 0.8 or more; 0.9 or more; 1 or more; or about 1.

[0054] [Equation 1]

[0055] Peak intensity ratio = I 200 / I 102

[0056] (I is the intensity value of each peak in the XRD pattern.)

[0057] According to one embodiment, the present invention provides a method for manufacturing a one-dimensional perovskite capping thin film, wherein the manufacturing method may include the steps of: preparing a three-dimensional perovskite layer; forming a precursor film by depositing a precursor solution comprising the following chemical formula 1 and an organic solvent on the three-dimensional perovskite layer; and heat-treating the precursor film.

[0058] According to one embodiment, the compound represented by Formula 1 in the precursor solution; and the organic solvent are as described above. The concentration of the compound represented by Formula 1 in the precursor solution may be 0.5 mM to 5 mM; 0.5 mM to 4 mM; 0.5 mM to 3 mM; 0.5 mM to 2 mM; or 0.5 mM to 1.5 mM.

[0059] According to one embodiment, the heat treatment step may be performed at a temperature of 50°C or higher; 80°C or higher; 100°C or higher; 80°C to 150°C; 80°C to 120°C and for 1 minute or more; 5 minutes or more; 10 minutes or more (or less); 20 minutes or more (or less); or for 8 minutes to 15 minutes.

[0060] According to one embodiment, the step of forming the precursor film may utilize a solution process and may refer to a process of forming a film using a liquid solvent, such as spin coating, spray coating, dip coating, inkjet printing, roll-to-roll printing, or screen printing.

[0061] According to one embodiment, the present invention may provide a perovskite solar cell comprising a photoactive layer in which a one-dimensional perovskite thin film of the present invention is introduced as a capping layer. Depending on the structure of the solar cell, the capping layer may be introduced on the bottom surface, the top surface, or both of the photoactive layer. Referring to FIG. 2, FIG. 2 exemplarily illustrates the configuration of a perovskite solar cell of the present invention according to one embodiment, and may include a first electrode layer (100), a first functional layer (200), a photoactive layer (300), a capping layer (400), a second functional layer (500), and a second electrode layer (600). According to one embodiment, the present invention may provide a perovskite solar cell in which a one-dimensional perovskite capping layer with a controlled cross-sectional plane is introduced between a light absorption layer (e.g., a three-dimensional perovskite layer) and a functional layer (e.g., an electron transport layer).

[0062] According to one embodiment, the present invention can improve device performance and promote interfacial electron extraction by introducing a one-dimensional perovskite capping layer (400) having a (n-type) cross-section (e.g., (200) plane) with high electron density, thereby forming appropriate energy levels between a perovskite-based photoactive layer (300) and a functional layer (e.g., electron transport layer). Additionally, the moisture stability of the device can be improved by utilizing it as a stable one-dimensional perovskite capping layer.

[0063] According to one embodiment, the first electrode layer and the second electrode layer may be applied without limitation as long as they are electrodes for driving a solar cell, and the first electrode and the second electrode may each be a cathode or an anode electrode. In some examples, the first electrode and the second electrode may include a transparent conductive material, a translucent conductive material, etc., and may include at least one selected from the group consisting of, for example, Co, Ir, Ta, Cr, Mn, Mo, Tc, W, Re, Fe, Sc, Ti, Ge, Sb, Al, Pt, Ni, Cu, Rh, Au, V, Nb, Ag, Pd, Zn, Ni, Si, Sn, and Ru; alloys thereof; and oxides thereof. The oxide may include at least one of a transparent conductive oxide (TCO) such as ITO, ZITO, ZIO, GIO, ZTO, FTO, AZO, GZO, etc. Additionally, it may further include carbon allotropes such as carbon nanotubes (CNT), graphene, and graphite, and conductive polymer materials such as polyacetylene, polyaniline, polythiophene, and polypyrrole. In some examples, the first electrode may be a transparent oxide electrode (e.g., ITO), and the second electrode may be a metal electrode (e.g., Al). In some examples, the thickness of the first electrode and the second electrode may be 10 nm to 200 nm; or 50 nm to 150 nm, respectively. In some examples, the first electrode may be a transparent electrode comprising a transparent oxide layer formed on a transparent substrate (e.g., a light-transmitting substrate such as glass, silicon, or a transparent polymer). In some examples, the second electrode layer may be formed on a second functional layer. In some examples, the first electrode and the second electrode may be a film, a membrane, or a pattern.

[0064] According to one embodiment, the first functional layer (200) and the second functional layer (500) may each be selected from a hole transport layer and an electron transport layer. For example, the first functional layer (200) may be a hole transport layer and the second functional layer (500) may be an electron transport layer.

[0065] According to one embodiment, the hole transport layer may be a hydrophobic hole transport layer as a hydrophobic functional layer. In some examples, the hydrophobic hole transport layer comprises Br-2PACz, I-2PACz, Me-2PACz, MeO-2PACz, Me-6PACz, MeO-4PACz, Me-4PACz, PTAA (poly(triarylamine), poly[bis(4-phenyl)(2,4,6-trimethylphenyl)amine]), cyclopenta-[2,1-b;3,4-b']-dithiophene, benzothiadiazole, diketopyrrolopyrrole, thieno[3,4-b]thiophene, benzodithiophene, carbazole, fluorene, and PEDOT:PSS It may include one or more selected from the group consisting of (poly(3,4-ethylenedioxythiophene) poly(styrenesulfonate), PS-PAA (polystyrene-polyacrylic acid block copolymer), poly-TPD (Poly(4-butylphenyl-diphenyl-amine)), PPV (polypheylene vinylene) and PVP (polyvinylpyrrolidone).

[0066] According to one embodiment, the electron transport layer is aluminum tris(8-hydroxyquinoline) (Alq3), lithium fluoride (LiF), lithium complex (8-hydroxy-quinolinato lithium, Liq), non-conjugated polymer, non-conjugated polymer electrolyte, conjugated polymer electrolyte (e.g., B3PYMPM, TPBi, 3TPYMB, BmPyPB, BSFM, B3PYMPM, BSFM, etc.), or n-type metal oxide, C 60 It can be formed using materials such as low-dimensional carbon-based materials. For example, the n-type metal oxide is, for instance, TiO₂. x It may be ZnO or Cs2CO3. Additionally, a self-assembled thin film of a metal layer may be used as the electron transport layer. The low-dimensional carbon-based material comprises low-elliptical carbon-based organic or inorganic materials, or both, and is, for example, C60, C70, C71, C76, C78, ​​C80, C82, C84, C92, PC60BM, PC61BM, PC 71 Fullerene compounds such as BM, ICBA, BCP, PC70BM, IC70BA, PC84BM, Indene C60, Indene C70, and endohydral fullerene; may include one or more selected from the group consisting of perylene, PTCDA, PTCBI, BCP (bathocuproine), Bphen (4,7-diphenyl-1,10-phenanthroline), TpPyPB, and DPPS, but are not limited thereto.

[0067] According to one embodiment, the thickness of the first functional layer (200) and the second functional layer (500) may be, respectively, 1 nm to 100 nm; 1 nm to 90 nm; 1 nm to 50 nm; 5 nm to 30 nm; or 10 nm to 20 nm. Preferably, it may be 10 nm to 20 nm. The thickness may be the thickness of each layer or the total thickness.

[0068] According to one embodiment, the thickness of the capping layer (400) may be 10 nm or more; 15 nm or more; 20 nm or more; 25 nm or more (or less); 30 nm or more (or less); or 20 nm to 30 nm.

[0069] According to one embodiment, an organic buffer layer (600) may be further included between the electron transport layer (500) and the second electrode (700). The organic buffer layer 600 includes BCP (Bathocuproine), TPD-Si2(4,4' bis[(ptrichlorosilylpropylphenyl)phenylamino]biphenyl), P3HTV (poly(3-hexyl-2,5-thienylene vinylene)), PHEDOT (poly[3,4-(1hydroxymethyl) ethylenedioxythiophene]), PSSA-g-PANI (poly(styrenesulfonic acid)-graft-poly(aniline)), PFT (poly[(9,9-dioctylfluorene)-co-N-(4-(1-methylpropyl)phenyl)diphenylamine]), TSPP (4,4' bis[(p-trichlorosilylpropylphenyl)phenylamino] biphenyl), TSPT It may be selected from (5,5'-bis[(p-trichlorosilylpropylphenyl)phenylamino]-2, 20-biphenyl), but is not limited thereto.

[0070] According to one embodiment, the solar cell comprises, as shown in FIG. 3, a first electrode layer (100); a hole transport layer (200) on the first electrode layer (100); a perovskite-based photoactive layer (300) on the hole transport layer (200); a one-dimensional perovskite capping layer (400) on the photoactive layer (300); an electron transport layer (500) on the capping layer (400); and a second electrode (700) on the electron transport layer (500), and may further comprise an organic buffer layer (600) between the electron transport layer (500) and the second electrode (700). The first electrode layer (100) may be a transparent electrode and the second electrode (700) may be a metal electrode, and the solar cell may be an inverted structure solar cell.

[0071] According to one embodiment, a method for manufacturing a perovskite solar cell of the present invention may include the steps of: forming a three-dimensional perovskite-based photoactive layer on a first functional layer (e.g., a hole transport layer) or a second functional layer; forming a one-dimensional perovskite precursor film on the three-dimensional perovskite-based photoactive layer; and heat-treating the one-dimensional perovskite precursor film. According to one embodiment, the method for manufacturing the present invention may provide a solar cell having a one-dimensional perovskite capping layer with a controlled cross-section that can improve electron extraction and moisture stability by introducing a thin one-dimensional perovskite capping layer through a simple solution process.

[0072] According to one embodiment, the step of forming the photoactive layer includes the step of forming a three-dimensional perovskite precursor film and the step of heat treatment, and the step of forming the three-dimensional perovskite precursor film utilizes a deposition or coating process, for example, spin coating, sputtering, CVD, ion-beam sputtering, reactive sputtering, ion-assisted deposition, HiTUS (High-target-utilization sputtering), HiPIMS (High-power impulse magnetron sputtering), gas flow sputtering, plasma sputtering, etc., and the deposition may utilize CVD, thermal evaporation, plasma sputtering, electron beam evaporation, atomic layer deposition (ALD), etc. The heat treatment step above may be performed after depositing the perovskite precursor at a temperature of 50°C or higher; 80°C or higher; 100°C or higher; or 80°C to 150°C and for 30 minutes or more; 1 hour or more; 2 hours or more; or 30 minutes to 1.5 hours. The above three-dimensional perovskite precursor film may utilize a precursor compound appropriately selected according to the aforementioned three-dimensional perovskite, for example, for ABX3 formation, a precursor compound related to methylammonium (A site: Methylammonium, MA), tin (B site: Sn), X site: (bromide (Br), chloride, Cl), etc., may be included, or a precursor compound related to formamidinium (A site: Formamidinium; FA), cesium (A site: Cs), lead (B site: Pb), and iodide (X site: I) may be utilized.

[0073] According to one embodiment, the step of forming a one-dimensional perovskite precursor film on the three-dimensional perovskite-based photoactive layer may be to prepare and deposit a one-dimensional perovskite precursor solution comprising Formula 1 and an organic solvent, and the step of heat-treating the precursor film may be to heat-treat at a temperature of 50°C or higher; 80°C or higher; 100°C or higher; or 80°C to 150°C and for 1 minute or more; 5 minutes or more; 10 minutes or more (or less); 20 minutes or more (or less); or 8 minutes to 15 minutes.

[0074] According to one embodiment, the electrode, functional layer, organic buffer layer, etc., which are components of the solar cell of the present invention, may utilize processes known in the technical field of the present invention. For example, a conductive material layer may be formed on a substrate coated with a conductive material layer on the substrate using sputtering, CVD, deposition, solution process, coating, printing, etc. For example, a second functional layer may be formed using sputtering, CVD, deposition, solution process, coating, printing, etc. In some examples, the step of forming the second electrode layer may involve forming a metal electrode by thermal evaporation. For example, the first functional layer and the second functional layer may be formed respectively on a lower substrate (e.g., the first electrode layer or a perovskite crystal film) using sputtering, CVD, deposition, coating (e.g., solution process coating) (e.g., spin coating), printing, etc. Preferably, thermal evaporation may be used. For example, the first functional layer and the second functional layer can be formed by thermal evaporation under temperature conditions of 20°C to 100°C. The sputtering mentioned above may utilize ion-beam sputtering, reactive sputtering, ion-assisted deposition, HiTUS (High-target-utilization sputtering), HiPIMS (High-power impulse magnetron sputtering), gas-flow sputtering, plasma sputtering, etc., and the deposition may utilize CVD, thermal evaporation, plasma sputtering, electron beam evaporation, atomic layer deposition (ALD), etc.The above coating may refer to a process of forming a film using a liquid solvent, such as a solution process, spin coating, spray coating, dip coating, inkjet printing, roll-to-roll printing, or screen printing.

[0075] Example 1

[0076] The device was fabricated according to the configuration of Fig. 3. An ITO-coated glass substrate was ultrasonically treated for 10 minutes while sequentially washing with deionized water, acetone, and isopropyl alcohol. Subsequently, the washed substrate was treated with UV-O3 for 60 minutes, transferred to an N2 glove box, and MeO-4PACz (1 mg mL in ethanol) -1 ) was spin-coated at 5000 rpm for 30 seconds and then annealed at 100 °C for 10 minutes. After cooling, the film was washed by spin-casting with ethanol solvent at 5000 rpm for 30 seconds. The 3D perovskite precursor solution was spin-coated at 500 rpm for 7 seconds and at 4000 rpm for 25 seconds. After 17 seconds, ethyl acetate (0.45 mL) was poured onto the perovskite layer during spin-coating. After thermal annealing at 100 °C for 1 hour, EMIM-I (0.5 mg / mL in tetrahydrofuran) was dynamically spin-coated at 5000 rpm for 30 seconds and then annealed at 100 °C for 10 minutes. A 30 nm thick C60 layer was first placed under high vacuum (< 5 × 10⁻⁶ -6 Evaporation rate of 0.3 Å s under Torr -1 It was deposited as follows. Next, under the same vacuum conditions, a 3.5 nm thick BCP (Bathocuproine; Xian polymer) layer was deposited at 0.2 Å s -1 It was deposited in [location]. Finally, a 100 nm thick silver (Ag) electrode was thermally deposited in a high vacuum. The device area of ​​13.5 mm² is defined by the patterned metal mask used during silver (Ag) deposition. The composition of the above three-dimensional perovskite precursor solution (total concentration 1.8 M) is as follows:

[0077] (1) Solute:

[0078] Formamidinium iodide 1.53M,

[0079] Cesium iodide 0.27M,

[0080] Lead (II) iodide 1.8M

[0081] (2) Solvent:

[0082] It contains dimethylformamide and dimethyl sulfoxide in a ratio of 7:3.

[0083] Example 2

[0084] The procedure was carried out in the same manner as Example 1, except that EMIM-I (0.5 mg / mL in IPA) was applied.

[0085] Evaluation example

[0086] (1) Shape control of 1D perovskite controlled by the dissociation constant (ξ) of the IL

[0087] FIG. 4 is a schematic diagram showing the shape deformation of a one-dimensional perovskite controlled by the dissociation constant (ξ) of the IL in an embodiment of the present invention, according to one embodiment.

[0088] In Fig. 4, the one-dimensional (1D) perovskite EMIMPbI3 is face-sharing [PbI3] - containing the 1D chain of octahedra Pcba It crystallizes in space group (61). EMIM +Cations exist in interchain vacancies to maintain charge balance. To investigate the crystal structure in more detail, EMIM-I and PbI2 were dissolved in DMSO at a 1:1 molar ratio, and the solvent was slowly evaporated in a vacuum oven to obtain EMIMPbI3. The resulting yellow 1D perovskite structure exhibits two distinct XRD peaks at 2θ = 10.0° and 10.2°, corresponding to the (200) and (102) planes, respectively. Additionally, each ionic liquid (IL) was dissolved at an equal concentration in isopropyl alcohol (IPA), a solvent used to prepare LDP / 3D heterostructures, and then treated onto a 3D perovskite film. All samples exhibited (200) and (102) plane peaks, confirming the formation of EMIMPbI3 in the perovskite layer. The relative peak intensity varies depending on the IL used. EMIMPbI3 treated with EMIM-H3CSO3 showed similar intensity for the (200) and (102) planes, whereas EMIMPbI3 treated with EMIM-I showed a much stronger (102) peak compared to the (200) peak. Changes in the overall morphology occurred due to differences in growth rate and size in the (200) and (102) planes. EMIMPbI3 formed with EMIM-H3CSO3 showed a rod-like shape, whereas 1D EMIMPbI3 formed with EMIM-I had a plate-like shape. Taken together, these results suggest that IL can control the facet-selective growth of EMIMPbI3 to ultimately determine the morphology of 1D EMIMPbI3.

[0089] (2) Morphology and dominant cross-section control of 1D perovskites through solvent control

[0090] Figure 5 shows an experimental process for controlling the morphology and dominant cross-section of a one-dimensional perovskite through solvent control in an embodiment of the present invention according to one embodiment, and an X-ray pattern of a perovskite film (i.e., EMIMPbI3) treated with EMIM-I dissolved in IPA and THF, respectively.

[0091] The present invention can improve electron extraction and device performance by controlling the dominant end face of EMIMPbI3 by adjusting the treatment solvent and forming EMIMPbI3 with an enhanced (200) plane, which is an electron-rich state (n-type). It can be observed that the (200) / (102) end face ratio of the one-dimensional perovskite (EMIMPbI3) changes depending on the change in the treatment solvent (IPA → THF). EMIMPbI3 with an enhanced (200) plane can be obtained through THF treatment.

[0092] Figure 6 shows the difference in electron density (below) according to the cross-section (top) of a one-dimensional perovskite (EMIMPbI3) in an embodiment of the present invention, according to one embodiment.

[0093] In FIG. 6, EMIMPbI3 is predominantly composed of (200) planes and (102) planes, and the (200) plane is [PbI3] - It is terminated by a unit and has an electron-rich state (n-type), and (102) plane is [EMIM + ] terminates in a unit and is relatively electron-deficient.

[0094] Figure 7 shows the difference in electron transport according to the cross-sectional control of a one-dimensional perovskite (EMIMPbI3) in an embodiment of the present invention, according to one embodiment.

[0095] In FIG. 7, EMIMPbI3 with a dominant (102) plane has a higher conduction band energy level than the perovskite layer, which prevents electrons from being easily extracted into the electron transport layer, leading to a degradation in device performance. The present invention forms an EMIMPbI3 with an enhanced n-type (200) plane that has a high electron density, thereby raising the Fermi level. As a result, n-type characteristics are imparted to the perovskite surface, making electron extraction easier.

[0096] FIG. 8 illustrates, according to one embodiment, PbI2, PbI2+EMIM-I, PbI2+EMIM-I+IPA (IPA), and PbI2+EMIM-I+THF (THF) in an embodiment of the present invention. 207 This shows the Pb NMR spectrum. All samples are dissolved in DMSO of the same concentration.

[0097] In Figure 8, for four solutions (PbI2 alone, PbI2+ EMIM-I, PbI2+ EMIM-I + IPA, and PbI2+ EMIM-I + THF) prepared at the same concentration in DMSO to evaluate the relative interaction strength between PbI2 and the solvent IPA or THF 207 The Pb nuclear magnetic resonance (NMR) spectrum was measured. The results are shown in Figure 8. Pure PbI2 at 138 ppm 207 It exhibits Pb resonance. Upon addition of THF, the peak shifts to a lower field than that of IPA, indicating that THF induces greater shielding rejection, resulting in stronger binding to PbI2 than IPA. Considering these characteristics, THF allows for the use of Pb 2+ Reducing the number of sites relatively EMIM + It can induce an environment rich in [a] and mimic the effect of strongly dissociating IL (ionic liquid).

[0098] FIG. 9 shows the UPS spectrum of an EMIM-I treated perovskite film in an embodiment of the present invention according to one embodiment, corresponding to (top) EMIM-I / IPA treated and (bottom) EMIM-I / THF treated perovskite.

[0099] FIG. 10 shows an energy level diagram of a 3D perovskite / 1D EMIMPbI3 heterostructure in an embodiment of the present invention according to one embodiment, comprising a perovskite photoactive layer (EMIM-I untreated), a perovskite (102) dominant 1D / 3D (EMIM-I / IPA treated) and a perovskite (200) enhanced 1D / 3D (EMIM-I / THF treated) and C 60 This is the energy level diagram.

[0100] As previously confirmed in the XRD patterns in Figures 9 and 10, changes in energy levels according to changes in the cross-section of the one-dimensional perovskite can be observed. When the treatment solvent is changed to tetrahydrofuran (THF), the (200) plane ratio of the one-dimensional perovskite (EMIMPbI3) increases, and by strengthening the ratio of the (200) plane with high electron density, an increase in the ferro level is induced, resulting in an energy level favorable for electron extraction.

[0101] FIG. 11 illustrates AM 1.5G and 100 mW cm⁻¹ in an embodiment of the present invention according to one embodiment. -2 This measures the JV characteristics of the peak performance of PeSCs under 1-sun illumination conditions. Figure 11 relates to PeSCs without EMIM-I treatment (control group) and with EMIM-I treatment. The cell active area is 0.135 cm² 2 The EMIM-I(THF) processed PeSC has the highest performance JV characteristics.

[0102] Figure 12 shows SEM images of perovskite films after treatment with EMIM-I dissolved in IPA and THF, respectively, in an embodiment of the present invention, according to one embodiment.

[0103] FIG. 13 shows KPFM images of perovskite films after treatment with EMIM-I dissolved in IPA and THF, respectively, in an embodiment of the present invention, according to one embodiment.

[0104] FIG. 14 shows the TPC measurement results of PeSCs in an embodiment of the present invention according to one embodiment, relating to PeSCs in the case without EMIM-I treatment (control group) and in the case with EMIM-I treatment.

[0105] FIG. 15 shows the stability of PeSC (ambient temperature and humidity without encapsulation) in ISOS-D1 (ambient temperature and humidity) in an embodiment of the present invention, evaluated via PCE in the case without EMIM-I treatment (control group) and in the case with EMIM-I treatment, according to one embodiment.

[0106] Table 1 shows the measurement results of photovoltaic parameters of the PeSCs prepared in the examples. Table 1 shows the photovoltaic parameters of the PeSCs containing the pure photoactive layer (control group), 1D EMIMPbI3 (EMIM-I(IPA)), and 1D EMIMPbI3 (EMIM-I(THF)), respectively.

[0107] [Table 1]

[0108]

[0109] In Figure 11, the change in performance of the solar cell can be confirmed through the solar cell JV curve.

[0110] In Fig. 12, changes in the shape of the one-dimensional perovskite according to changes in the (200) / (102) cross-sectional ratio can be observed.

[0111] In Figure 13, changes in the Fermi level of the perovskite surface depending on the treatment solvent can be observed. In Figure 14, improvements in charge extraction (transient photocurrent measurement) according to changes in the cross-sectional view of the one-dimensional perovskite can be observed. In Figure 15, improvements in moisture stability due to the introduction of one-dimensional perovskite can be observed, and in Table 1, improvements in the characteristics of the perovskite solar cell can be observed. That is, due to the rise in the Fermi level, an energy level that facilitates electron extraction is obtained, and consequently, it can be confirmed that device performance is improved. In addition, it can be confirmed that moisture stability (50-60 RH%) is improved by using thermodynamically stable one-dimensional perovskite as a capping layer.

[0112] According to one embodiment, FIG. 16 shows the change in the XRD pattern of a perovskite film treated with EMIM-I(THF) in an embodiment of the present invention over 96 hours in ambient air (50-60 RH%). The perovskite film treated with EMIM-I(THF) maintains a black appearance for 96 hours when stored in ambient air with a relative humidity of 50-60%, and through X-ray diffraction analysis, it can be confirmed that the crystal structure of the perovskite treated with EMIM-I(THF) did not change for 96 hours when stored in ambient air with a relative humidity of 50-60% because a low ξ IL was used.

[0113] Figure 17 shows the JV curve of PeSC according to the concentration of EMIM-I dissolved in THF in an embodiment of the present invention, according to one embodiment. It can be confirmed that for high-performance PeSC, the optimal concentration of EMIM-I in THF is 0.5 mg / ml.

[0114] The present invention is a strong Pb 2+- A controlled geometry of rod-shaped 1D EMIMPbI3 can be realized by using a coordination solvent (THF) and an anti-dissociation IL (EMIM-I) together. As a result, EMIM-I (THF) treated with PeSC exhibits a high PCE (electrolyte efficiency) of 25.40% and excellent moisture and thermal stability. This improvement in properties is attributed to the hydrophobicity and chemically robust surface characteristics of the 1D capping layer. In other words, facet engineering of the 1D perovskite through solvent-IL interactions precisely controls crystal orientation and morphology, thereby improving both the efficiency and stability of the pin PeSC, and by integrating a functional interface layer of the 1D perovskite, a high-performance and durable device structure can be provided.

[0115] Although the embodiments have been described above with reference to limited examples and drawings, those skilled in the art can make various modifications and variations from the description above. For example, suitable results may be achieved even if the described techniques are performed in a different order than described, and / or the described components are combined or assembled in a form different from described, or replaced or substituted by other components or equivalents. Therefore, other implementations, other embodiments, and equivalents to the claims below are also within the scope of the claims.

Claims

Claim 1 A one-dimensional perovskite capping layer formed on a three-dimensional perovskite layer, wherein the one-dimensional perovskite capping layer is a (200) plane and a (102) plane in which facet peaks are dominant in the XRD pattern, and the facets are a (200) plane and a (102) plane, and the peak intensity of the XRD pattern of the (200) plane is higher than that of the (102) plane, and the one-dimensional perovskite capping layer is a (200) plane enhanced one-dimensional perovskite, or wherein the one-dimensional perovskite capping layer has a facet peak intensity ratio according to the following formula greater than 0.5: [Formula 1] Peak intensity ratio = I 200 / I 102 (I is the intensity value of each peak in the XRD pattern.) Claim 2 A one-dimensional perovskite capping thin film according to claim 1, wherein the capping layer comprises a perovskite compound represented by ABX3, wherein A is a cation derived from the following Chemical Formula 1, B is lead (Pb), and X is an anion selected from halogens: [Chemical Formula 1] (R1, R2, and R3 are each selected from hydrogen, C1 to C10 alkyl groups, C2 to C10 alkenyl groups, benzyl groups, and aryl groups, and X' is a halogen, NO3 - and H3CSO3 - (Selected from.) Claim 3 A one-dimensional perovskite capping thin film according to claim 2, wherein the capping layer comprises at least one perovskite compound selected from [Edimim(1-ethyl-2,3-dimentylimidazolium)]-PbX3, [BMIM(1-butyl-3-methylimidazolium ion)]-PbX3, [EMIM(1-ethyl-3-methylimidazolium)]-PbX3, [VMIM(1-vinyl-3-methylimidazolium)]-PbX3, [DMIM(1,3-dimethylimidazolium)]-PbX3, and [BzMIM(1-benzyl-3-methylimidazolium)]-PbX3. Claim 4 A one-dimensional perovskite capping thin film according to claim 2, wherein the one-dimensional perovskite capping layer is formed by depositing and heat treating a precursor solution comprising a compound represented by the chemical formula 1; and at least one organic solvent among a hydrocarbon solvent, a carbon chloride solvent, and an ether solvent having a dielectric constant of 8 or less and a dipole moment of 2 or less or both, on a three-dimensional perovskite layer. Claim 5 A one-dimensional perovskite capping film according to claim 4, wherein the solvent comprises at least one of pentane, hexane, benzene, heptane, toluene, 1,4-dioxane, diethyl ether, tetrahydrofuran (THF), and chloroform. Claim 6 delete Claim 7 delete Claim 8 A one-dimensional perovskite capping thin film according to claim 1, wherein the peak ratio of the cross-section is 0.7 or higher. Claim 9 A one-dimensional perovskite capping thin film according to claim 1, wherein the one-dimensional perovskite capping layer comprises a divalent metal identical to the perovskite layer. Claim 10 A method for manufacturing a one-dimensional perovskite capping thin film according to claim 1, wherein the manufacturing method comprises: a step of preparing a three-dimensional perovskite layer; a step of forming a precursor film by depositing a precursor solution comprising the following chemical formula 1 and an organic solvent on the three-dimensional perovskite layer; and a step of heat-treating the precursor film; a method for manufacturing a one-dimensional perovskite capping thin film: [Chemical Formula 1] (R1, R2, and R3 are each selected from hydrogen, C1 to C10 alkyl groups, C2 to C10 alkenyl groups, benzyl groups, and aryl groups, and X' is a halogen, NO3 - and H3CSO3 - (Selected from.) Claim 11 A method for manufacturing a one-dimensional perovskite capping thin film according to claim 10, wherein the heat treatment step is performed at 80°C to 150°C for at least 1 minute. Claim 12 A method for preparing a one-dimensional perovskite capping thin film according to claim 10, wherein the precursor solution comprises a compound represented by the chemical formula 1; and at least one organic solvent among a hydrocarbon solvent, a carbon chloride solvent, and an ether solvent having a dielectric constant of 8 or less and a dipole moment of 2 or less or both. Claim 13 A method for preparing a one-dimensional perovskite capping film according to claim 12, wherein the solvent comprises at least one of pentane, hexane, benzene, heptane, toluene, 1,4-dioxane, diethyl ether, tetrahydrofuran (THF), and chloroform. Claim 14 A perovskite solar cell comprising: a first electrode layer; a hole transport layer on the electrode layer; a perovskite-based photoactive layer on the hole transport layer; a one-dimensional perovskite capping layer on the photoactive layer; an electron transport layer on the capping layer; and a second electrode on the electron transport layer; wherein the one-dimensional perovskite capping layer is a one-dimensional perovskite capping thin film of claim 1. Claim 15 A perovskite solar cell according to claim 14, wherein the thickness of the capping layer is 1 nm or more. Claim 16 A perovskite solar cell according to claim 14, further comprising an organic buffer layer between the electron transport layer and the second electrode. Claim 17 A method for manufacturing a perovskite solar cell according to claim 14, wherein the method comprises: a step of forming a perovskite-based photoactive layer on a hole transport layer; a step of forming a precursor film by depositing a precursor solution comprising the following chemical formula 1 and an organic solvent on the perovskite-based photoactive layer; and a step of heat-treating the precursor film; a method for manufacturing a perovskite solar cell: [Chemical Formula 1] (R1, R2, and R3 are each selected from hydrogen, C1 to C10 alkyl groups, C2 to C10 alkenyl groups, benzyl groups, and aryl groups, and X' is a halogen, NO3 - and H3CSO3 - (Selected from.) Claim 18 A method for manufacturing a perovskite solar cell according to claim 17, wherein the step of forming the photoactive layer is heat-treating at 80°C to 150°C for 30 minutes or more after depositing a three-dimensional perovskite precursor. Claim 19 A method for manufacturing a perovskite solar cell according to claim 17, wherein the step of heat-treating the precursor film is heat-treating at 80°C to 150°C for at least 1 minute.

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