Perovskite solar cell and method of manufacturing perovskite solar cell

Abstract

To provide a perovskite solar cell which uses a counter electrode containing carbon and achieves a thin thickness and flexibility while suppressed in decrease of photoelectric conversion efficiency, and a method of manufacturing a perovskite solar cell.SOLUTION: A perovskite solar cell 10 includes an anodic electrode 62 disposed adjacent to a hole transport layer 5. The anodic electrode 62 comprises a carbon electrode containing graphite fillers and has a large conductivity along a forward direction where current flows as compared with a conductivity along an orthogonal direction orthogonal to the forward direction.SELECTED DRAWING: Figure 4

Description

[Technical Field]

[0001] The present disclosure relates to perovskite solar cells and methods for manufacturing perovskite solar cells. [Background technology]

[0002] Solar cells generally use elements such as silicon, compound semiconductors, and organic semiconductors. Recently, perovskite solar cells have been attracting attention due to their high light-harvesting capacity, thin film construction, and low cost.

[0003] Patent Document 1 discloses a perovskite solar cell using a carbon electrode. In this solar cell, to give the carbon electrode the dual functions of hole transport and conductivity, carbon nanospheres coated with transition metal chalcogenide, which has semiconducting properties, are produced using a transition metal chalcogenide ammonium salt, an emulsifier, water, and a monomer as raw materials. These are then mixed with other carbon materials to produce a carbon slurry, which serves as the carbon electrode. The carbon electrode has a thickness of 10 μm to 20 μm. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Chinese Patent Application Publication No. 115985999 Summary of the Invention [Problem to be solved by the invention]

[0005] The perovskite solar cell disclosed in Patent Document 1 has a power generation efficiency of 8.05% to 9.78%, less than half that of perovskite solar cells using gold electrodes. This is due to the extremely low electrical conductivity of carbon compared to gold. Conventional carbon electrodes are primarily made of carbon materials with hole transport layer functionality, which makes it difficult to improve the electrical conductivity of the carbon electrodes due to poor carbon crystallinity. This results in a significant decrease in power generation efficiency compared to solar cells using gold electrodes. Conversely, increasing the thickness of the carbon electrodes to ensure the necessary electrical conductivity sacrifices the thinness and flexibility that are characteristic of perovskite solar cells.

[0006] Therefore, there is a demand for a thin, flexible perovskite solar cell that uses a counter electrode containing carbon and that suppresses a decrease in photoelectric conversion efficiency, as well as a method for manufacturing such a perovskite solar cell. [Means for solving the problem]

[0007] One embodiment of a perovskite solar cell according to the present disclosure is a perovskite solar cell having an anode electrode disposed adjacent to a hole transport layer, wherein the anode electrode is made of a carbon electrode containing graphite filler, and the electrical conductivity along a forward direction, in which current flows, is greater than the electrical conductivity along an orthogonal direction perpendicular to the forward direction.

[0008] According to this embodiment, the anode electrode is made of a carbon electrode containing graphite filler, and the conductivity in the forward direction, in which current flows, is higher than the conductivity in the orthogonal direction perpendicular to the forward direction. Higher conductivity allows a larger current to flow with lower resistance, resulting in higher photoelectric conversion efficiency. Therefore, by configuring the current to flow in the forward direction, a perovskite solar cell can be obtained that has a highly conductive anode electrode and that suppresses a decrease in photoelectric conversion efficiency.

[0009] One embodiment of the method for manufacturing a perovskite solar cell according to the present disclosure is the method for manufacturing the perovskite solar cell described above, and further includes an anode forming step of applying a carbon paste containing the graphite filler onto the hole transport layer in a direction parallel to the forward direction, and drying the carbon paste to form the anode.

[0010] According to this embodiment, the anode is formed by a simple method in which a carbon paste containing graphite filler is applied onto the hole transport layer in a direction parallel to the forward direction and then dried. This makes it possible to easily manufacture a perovskite solar cell that has a highly conductive anode and in which a decrease in photoelectric conversion efficiency is suppressed. [Brief explanation of the drawings]

[0011] [Figure 1] FIG. 1 is a schematic cross-sectional view of a perovskite solar cell. [Figure 2] FIG. 1 is a perspective view from above of a perovskite solar cell. [Figure 3] FIG. 1 is a cross-sectional view illustrating the power generation principle of a perovskite solar cell. [Figure 4] FIG. 1 is an explanatory diagram showing a procedure for fabricating a perovskite solar cell. DETAILED DESCRIPTION OF THE INVENTION

[0012] Hereinafter, embodiments of the perovskite solar cell according to the present disclosure will be described in detail with reference to the drawings. Note that the embodiments described below are examples for explaining the perovskite solar cell, and the perovskite solar cell is not limited to these embodiments. Therefore, the perovskite solar cell according to the present disclosure can be implemented in various forms without departing from the spirit of the present disclosure.

[0013] [Basic structure of solar cells] As shown in FIGS. 1 and 2 , a perovskite solar cell 10 according to this embodiment (hereinafter simply referred to as the solar cell 10) includes a substrate 2 and a laminate 11 provided on the substrate 2. The substrate 2 includes a transparent substrate 21 and a transparent conductive film 22. The laminate 11 includes a blocking layer 3, a power generation layer 4, and a hole transport layer 5. The blocking layer 3 is provided on the transparent conductive film 22 and transfers electrons to the transparent conductive film 22, while separating the hole transport layer 5 from the transparent conductive film 22 to prevent recombination of electrons and holes (reverse electron transfer). The power generation layer 4 is provided on the blocking layer 3 and is formed by laminating a perovskite layer 44, which is excited by light to generate electrons, on a porous semiconductor 41. The hole transport layer 5 is provided on the power generation layer 4 and allows holes generated in the perovskite layer 44 to pass through. Furthermore, a photoelectrode 61 that emits electrons is provided on the surface of the blocking layer 3 via the transparent conductive film 22, and a counter electrode 62 (an example of an anode electrode) that receives electrons is provided on the surface of the hole transport layer 5. The counter electrode 62 is formed from the surface of the hole transport layer 5, passing over the side surfaces of the hole transport layer 5 and the perovskite layer 44, and extending to the surface of the blocking layer 3. Hereinafter, the photoelectrode 61 and the counter electrode 62 will be collectively referred to as electrode 6. The arrangement of the electrode 6 is not particularly limited as long as it allows electron transfer; for example, the photoelectrode 61 may be formed by connecting a conductor to the transparent conductive film 22. Furthermore, to increase the durability of the solar cell 10, the counter electrode 62 may be protected by a transparent substrate 21 or the like.

[0014] The transparent substrate 21 is made of a light-transmitting material. Examples of the transparent substrate 21 include a transparent glass substrate, a frosted semi-transparent glass substrate, and a transparent resin substrate. Examples of the transparent conductive film 22 include fluorine-doped tin oxide (FTO), tin oxide (SnO), tin-doped indium oxide (ITO), zinc oxide (ZnO), and aluminum-doped zinc oxide (AZO).

[0015] Metal oxides are suitable for the blocking layer 3 and the porous semiconductor 41, and examples thereof include titanium dioxide (TiO2), zinc oxide (ZnO), niobium oxide (Nb2O5), tin dioxide (SnO2), and aluminum oxide (Al2O3). In particular, it is preferable to use a sintered body of titanium dioxide (TiO2), which can secure a large surface area for stacking the perovskite layer 44. Furthermore, a portion of the blocking layer 3 extends into a recess 221 formed by removing a portion of the transparent conductive film 22 to form the insulating layer 31, thereby dividing the transparent conductive film 22 into two. In the blocking layer 3, electrons can move in the stacking direction, but have difficulty moving laterally, which is perpendicular to the stacking direction. Furthermore, electrons cannot move between the two transparent conductive films 22 separated by the insulating layer 31. In other words, electrons that enter the blocking layer 3 move smoothly in the stacking direction of the transparent conductive film 22 and are supplied to the photoelectrode 61, but since the insulating layer 31 prevents them from moving laterally toward the counter electrode 62, there is no short circuit between the photoelectrode 61 and the counter electrode 62.

[0016] The perovskite layer 44 is an organic-inorganic hybrid compound. Specifically, the perovskite layer 44 is produced by reacting a compound composed of lead and a halogen element X (PbX2, where X = the halogen element) with methylammonium iodide (CH3NH3I; hereinafter, sometimes abbreviated as "MAI"). Specifically, a solution containing lead and the halogen element X (e.g., a solution of PbI2 in N,N-dimethylformamide) is infiltrated into the pores of the porous semiconductor 41, dried, and then immersed in a mixed solution of MAI, whereby crystals of the perovskite compound (CH3NH3PbI3 when X = I) that forms the perovskite layer 44 are rapidly produced. The halogen element X can be iodine, bromine, chlorine, or the like, and iodine, which has high morphological stability, is preferably used. In addition, halogen element X was converted into mixed cation-mixed halide (FAPbI3) using MABr and 0.2M lead bromide (PbBr2), and FAI and lead iodide (PbI2). 1-x (MAPbBr3) x ) may be used. In this case, for example, (FAPbI3) 0.85 (MAPbBr3)0.15 etc. can be suitably used.

[0017] A hole transport material described later is used for the hole transport layer 5. For the photoelectrode 61, for example, an elemental metal or alloy of a metal such as gold, platinum, silver, or copper, or an oxide conductor such as fluorine-doped tin oxide (FTO) or tin-doped indium oxide (ITO) is used.

[0018] The counter electrode 62 is a carbon electrode. The counter electrode 62 of this embodiment contains graphite filler and carbon black. The counter electrode 62 of this embodiment is a carbon electrode with improved conductivity due to the graphite filler being oriented (imparting orientation).

[0019] Next, the principle of how solar cell 10 generates electricity will be described with reference to Figure 3. When light such as sunlight or room light is incident from the transparent substrate 21 side, this incident light passes through substrate 2 and blocking layer 3 without being absorbed much, and most of it reaches power generation layer 4. When the incident light that has reached power generation layer 4 is irradiated onto perovskite layer 44, this perovskite layer 44 absorbs the light energy and becomes excited. When this excitation raises the energy level of perovskite layer 44 to a predetermined level higher than the conduction band potential of the metal oxide that is the porous semiconductor 41, electrons are injected from perovskite layer 44 into porous semiconductor 41. The injected electrons pass through blocking layer 3 and are collected by photoelectrode 61.

[0020] Meanwhile, holes generated in the perovskite layer 44 reach the counter electrode 62 via the hole transport layer 5, where they recombine with electrons that have passed through the external load 7. In other words, a potential gradient is generated between the photoelectrode 61 and the counter electrode 62, and power can be supplied by connecting the external load 7 between the two electrodes. [Example]

[0021] [Solar cell fabrication procedure] <Example> Next, an example of the solar cell 10 according to this embodiment will be described. First, a manufacturing procedure for the solar cell 10 will be described with reference to FIG. 4. The solar cell 10 can be manufactured with reference to known techniques such as Michael Saliba et al., "Correction to 'How to Makeover 20% Efficient Perovskite Solar Cells in Regular (nip) and Inverted (pin) Architectures'," Chem. Mater., 2018, 30, 4193-4218.

[0022] First, a transparent conductive film 22 is formed on a transparent substrate 21 to prepare the substrate 2. The transparent conductive film 22 is laminated on the transparent substrate 21 by, for example, chemical vapor deposition (CVD) or sputtering. Next, laser scribing is performed to partially remove the transparent conductive film 22, forming recesses 221 for the insulating layer 31, followed by cleaning. Next, a blocking layer 3 is formed over the entire surface of the substrate 2 by atomic layer deposition (ALD) or spray pyrolysis (SPD). The blocking layer 3 is preferably formed as a dense TiO layer. Next, a porous semiconductor 41, which is a nanoparticle sintered layer, is formed near the center of the masked substrate 2 and blocking layer 3. The porous semiconductor 41 is preferably formed as a porous layer of TiO (p-TiO). This porous semiconductor 41 is formed by diluting nanoparticle paste with a solvent, applying it by spin coating at a rotation speed of 4000 rpm to 6000 rpm, drying it, removing the masking, and heating it at 450°C to 550°C to sinter it.

[0023] Next, for example, a solution of PbI2 in N,N-dimethylformamide is prepared and dropped onto the porous semiconductor 41. After that, the solution is permeated into the pores (p-TiO2) and excess solution is removed by spin coating at a rotation speed of, for example, 5000 rpm to 8000 rpm. The solution is then dried at 60°C to 120°C (preferably 70°C to 90°C) to form a PbI2 layer.

[0024] The substrate 2, blocking layer 3, and porous semiconductor 41 permeated with lead iodide are immersed in an isopropyl alcohol solution (2 mg / ml to 20 mg / ml) of MAI (CH3NH3I) at 0°C to 80°C (preferably at room temperature) (MAI immersion method). PbI2 and MAI react to form a perovskite compound [(CH3NH3)PbI3(MAPbI3)] as a perovskite layer 44 inside and on the pores of the porous semiconductor 41, and then the porous semiconductor 41 is rinsed with pure isopropyl alcohol solution and dried at 60°C to 120°C (preferably 70°C to 100°C). The mixed cation-mixed halide ((FAPbI3) 1-x (MAPbBr3) x )-based perovskite compounds can also be prepared in a similar manner.

[0025] The above fabrication procedure involves controlling the crystal growth of the perovskite compound that forms the perovskite layer 44 in two steps, but this can also be done in one step. For example, a perovskite ((CH3NH3)PbI3) solution is permeated into the pores of the porous semiconductor 41 by spin coating. Next, toluene is added dropwise during spinning to precipitate microcrystals and create a mirror-finished surface (poor solvent precipitation method).

[0026] The hole transport material according to this example (e.g., Spiro-OMeTAD) is prepared as a 60 mg / ml to 90 mg / ml chlorobenzene solution. The solution is dropped onto the perovskite layer 44, excess solution is removed by spin coating, and the solution is dried to form the hole transport layer 5. An additive such as TPFB may be added to the hole transport material. When TPFB is added, the TPFB content of the hole transport material is preferably 0.01 wt % to 100 wt %, and more preferably 0.1 wt % to 50 wt %. For example, the hole transport material according to this example is weighed out to a concentration of 30 mM, and TPFB equivalent to 10 wt % is added. The hole transport layer 5 can be formed by dissolving these in chlorobenzene. The thickness of the hole transport layer 5 in this example is 200 nm.

[0027] The above steps from forming the PbI2 layer to forming the hole transport layer 5 are preferably carried out in a dry nitrogen atmosphere such as in a glove box. Finally, the electrode 6 is formed. The photoelectrode 61 is formed by adhering a thin film of gold or the like to the surface of the blocking layer 3 by vacuum deposition or the like.

[0028] As described above, the counter electrode 62 is a carbon electrode containing graphite filler and carbon black. In this embodiment, the counter electrode 62 is formed using a solution (hereinafter also referred to as carbon paste 62a) in which graphite filler, carbon black, a resin binder, and a stabilizer component (hereinafter referred to as binder, etc.) are dispersed in a solvent. The graphite filler has a flake (scale-like) shape with a length of 10 μm to 25 μm and a thickness of less than 5 μm. The binder, etc. is made of resin with a content of 1.0 wt % to 18 wt %. The binder, etc. is preferably an acrylic-based, fluorine-based, ethylene oxide-based, paraffin-based, wax-based, anionic surfactant, cationic surfactant, amphoteric surfactant, nonionic surfactant, etc. The solvent is preferably an alcohol, such as methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, 2-butanol, tert-butanol, or 1-pentanol. In the carbon paste 62a, graphite filler, carbon black, binder, etc. account for 20% to 45% by weight, and the solvent accounts for 80% to 55% by weight, which gives the carbon paste 62a a viscosity of 600 cps to 2000 cps, which is optimal for the anode electrode formation process described below.

[0029] The anode formation process, which is a method for forming the counter electrode 62, is described below. In the anode formation process, first, the carbon paste 62a described above is applied onto the hole transport layer 5. Then, the coater 70 is moved to spread and coat the carbon paste 62a on the hole transport layer 5. When the coater 70 is moved, the gap between the coater 70 and the hole transport layer 5 is 30 μm to 100 μm, and the movement speed of the coater 70 is 3 mm / sec to 20 mm / sec. Hereinafter, the movement direction of the coater 70 when applying the carbon paste 62a is referred to as the forward direction. If the gap between the coater 70 and the hole transport layer 5 is less than 30 μm, the hole transport layer 5 may be adversely affected during the coating process. If it exceeds 100 μm, the thickness of the counter electrode 62 becomes too large. If the movement speed of the coater 70 is less than 3 mm / sec, production efficiency decreases, and if it exceeds 20 mm / sec, the counter electrode 62 may not be evenly formed.

[0030] When the coater 70 is moved in the forward direction to apply the carbon paste 62a, the length direction of the graphite filler particles is aligned approximately parallel to the forward direction. The carbon paste 62a is then dried to evaporate the solvent. The solvent is evaporated, for example, by heating at 80°C for 30 minutes. This dries the residual binder and the carbon film, resulting in a carbon film. In the resulting carbon film, as described above, the length direction of the graphite filler particles is aligned approximately parallel to the forward direction. Therefore, the graphite filler particles in the carbon film have orientation, and the orientation direction of the graphite filler particles is the same as the forward direction. In other words, by moving the coater 70 in the direction A indicated by the arrow in FIG. 4 (hereinafter also referred to as the coating direction A), the movement direction of the coater 70 and the orientation direction of the graphite filler particles in the carbon film can be made the same. The coating direction A and the movement direction of the coater 70 are the same as the forward direction.

[0031] If the sheet resistance (thickness of the carbon film) is not equal to or less than the desired value after the carbon film is formed, this indicates that the carbon film is too thin. Therefore, it is necessary to repeatedly apply and dry the carbon paste 62a to thicken the carbon film until the sheet resistance reaches the desired value. However, in this example, the gap between the coater 70 and the hole transport layer 5 is set relatively large, and the carbon film is formed once to obtain a counter electrode 62 with the desired thickness of 30 μm. A perovskite solar cell 10 having a 30 μm thick counter electrode 62, which is a carbon electrode, is as thin and flexible as a perovskite solar cell having a gold electrode.

[0032] In the counter electrode 62 of this embodiment, the graphite filler is oriented, and therefore the conductivity varies depending on the direction of current flow in the counter electrode 62. Specifically, the conductivity of the counter electrode 62 is highest when a current is passed through the counter electrode 62 in the direction of orientation of the graphite filler, i.e., the forward direction. Therefore, the forward direction is the direction in which the conductivity of the counter electrode 62 is highest, and passing a current in the forward direction results in the smallest sheet resistance.

[0033] For an example of solar cell 10 manufactured by the above-described manufacturing method, the sheet resistance, volume resistance, conductivity, and photoelectric conversion efficiency of counter electrode 62 were measured when a current was passed along coating direction A, which is parallel to the movement direction of coater 70 in Figure 4, and when a current was passed along direction B (hereinafter also referred to as coating direction B), which is perpendicular to the movement direction of coater 70. The measurement results are shown in Table 1 below.

[0034] [Table 1]

[0035] From Table 1, in the solar cell 10 of this example in which a current was passed along the coating direction A parallel to the moving direction of the coater 70, the resistance value of the counter electrode 62 was 9 Ω / sq and the volume resistance value was 2.7×10 -4Ω·m, conductivity was 3703.7 S / m, and photoelectric conversion efficiency was 14%. On the other hand, in the solar cell 10 of this example in which a current was passed along the coating direction B perpendicular to the moving direction of the coater 70, the resistance value of the counter electrode 62 was 12 Ω / sq, and the volume resistance value was 3.6×10 -4 The measured values ​​were Ω·m, conductivity 2777.8 S / m, and photoelectric conversion efficiency 9%. That is, the solar cell 10 of this example in which current was passed along coating direction A had 0.75 times the resistance and volume resistance, 1.33 times (more than 1.2 times) the conductivity, and 1.56 times the photoelectric conversion efficiency of the solar cell 10 of this example in which current was passed along coating direction B. This demonstrates that the solar cell 10 of this example in which current was passed along coating direction A exhibited better characteristics in all measured items than the solar cell 10 in which current was passed along coating direction B.

[0036] Generally, the resistance of the counter electrode 62 in a perovskite solar cell is preferably 20 Ω / sq or less, and more preferably 10 Ω / sq or less. The resistance of the solar cell 10 of this embodiment in coating direction A is 9 Ω / sq, satisfying the requirement for a more desirable resistance value. Furthermore, the photoelectric conversion efficiency of the solar cell 10 of this embodiment in coating direction A is 14%. This is 93% compared to the average photoelectric conversion efficiency of 15% for perovskite solar cells using a gold counter electrode. Despite being a carbon electrode, the decrease in photoelectric conversion efficiency compared to a gold electrode is suppressed to only 7%. Furthermore, because the counter electrode 62 of the solar cell 10 of this embodiment is a carbon electrode, it is more cost-effective than gold. Therefore, the solar cell 10 of this embodiment is practical in all respects: resistance, photoelectric conversion efficiency, and cost.

[0037] In the above example, the carbon film was formed once to obtain a counter electrode 62 with a film thickness of 30 μm and a sheet resistance of 9 Ω / sq. However, if a lower sheet resistance is required, the gap between the coater 70 and the hole transport layer 5 may be narrowed more than in the above example, and the carbon paste 62a may be applied and dried, and this process may be repeated multiple times. That is, the gap may be narrowed to form a carbon film thinner than the desired film thickness, and this process may be repeated multiple times. This further enhances the orientation of the graphite filler, allowing a counter electrode 62 with a desired film thickness and low sheet resistance to be obtained.

[0038] [Summary of the above embodiment] Hereinafter, the perovskite solar cell (10) described in the above embodiment will be considered to have the following configuration.

[0039] <1> One embodiment of the perovskite solar cell (10) is a perovskite solar cell (10) having an anode electrode (62) disposed adjacent to the hole transport layer (5), the anode electrode (62) being made of a carbon electrode containing graphite filler, and having a higher conductivity along a forward direction in which current flows than along an orthogonal direction perpendicular to the forward direction.

[0040] In this configuration, the anode electrode (62) is made of a carbon electrode containing graphite filler, and its conductivity in the forward direction, in which current flows, is higher than the conductivity in the orthogonal direction perpendicular to the forward direction. Higher conductivity allows a larger current to flow with lower resistance, resulting in higher photoelectric conversion efficiency. Therefore, by configuring the current to flow in the forward direction, a perovskite solar cell (10) can be obtained that has a highly conductive anode electrode (62) and that suppresses a decrease in photoelectric conversion efficiency.

[0041] <2> the above <1> In the perovskite solar cell (10) described above, it is preferable that the electrical conductivity of the anode electrode (62) in the forward direction is at least 1.2 times the electrical conductivity in the perpendicular direction.

[0042] According to this configuration, the conductivity of the anode electrode (62) in the forward direction is at least 1.2 times the conductivity in the orthogonal direction. Therefore, by configuring the anode electrode (62) so that current flows in the forward direction, it is possible to obtain a perovskite solar cell (10) having an anode electrode (62) with high conductivity and in which a decrease in photoelectric conversion efficiency is suppressed.

[0043] <3> the above <1> or <2> In the method for manufacturing a perovskite solar cell (10) described above, it is preferable to include an anode electrode formation step in which a carbon paste (62a) containing a graphite filler is applied onto the hole transport layer (5) in a direction parallel to the forward direction and then dried to form the anode electrode (62).

[0044] According to this method, the anode electrode (62) is formed by a simple method of applying a carbon paste (62a) containing graphite filler along a direction parallel to the forward direction onto the hole transport layer (5) and drying it. This makes it possible to easily manufacture a perovskite solar cell (10) having a highly conductive anode electrode (62) and in which a decrease in photoelectric conversion efficiency is suppressed.

[0045] <4> the above <3> In the method for manufacturing a perovskite solar cell (10) described above, it is preferable that the anode electrode formation step applies a carbon paste (62a) onto the hole transport layer (5) by moving a coater (70) in a direction parallel to the forward direction, the viscosity of the carbon paste (62a) is 600 cps or more and 2000 cps or less, the gap between the coater (70) and the hole transport layer (5) is 30 μm or more and 100 μm or less, and the moving speed of the coater (70) is 3 mm / sec or more and 20 mm / sec or less.

[0046] By forming the anode electrode (62) in the anode electrode formation step under the conditions of this method, it is possible to easily manufacture a perovskite solar cell (10) having a highly conductive anode electrode (62) and suppressing a decrease in photoelectric conversion efficiency. [Industrial Applicability]

[0047] The present disclosure is applicable to perovskite solar cells and methods for manufacturing perovskite solar cells. [Explanation of symbols]

[0048] 5: hole transport layer, 10: perovskite solar cell, 62: counter electrode (anode electrode), 62a: carbon paste, 70: coater

Claims

1. 1. A perovskite solar cell having an anode electrode disposed adjacent to a hole transport layer, The anode electrode is a carbon electrode containing graphite filler, and the electrical conductivity along a forward direction in which current flows is greater than the electrical conductivity along an orthogonal direction perpendicular to the forward direction.

2. 2. The perovskite solar cell according to claim 1, wherein the electrical conductivity of the anode electrode along the forward direction is 1.2 times or more than the electrical conductivity along the orthogonal direction.

3. A method for producing a perovskite solar cell according to claim 1 or 2, anode electrode formation step of applying a carbon paste containing the graphite filler onto the hole transport layer along a direction parallel to the forward direction and drying the carbon paste to form the anode electrode.

4. the anode electrode forming step includes applying the carbon paste onto the hole transport layer by moving a coater in a direction parallel to the forward direction; The viscosity of the carbon paste is 600 cps or more and 2000 cps or less, a gap between the coater and the hole transport layer is 30 μm or more and 100 μm or less; The method for producing a perovskite solar cell according to claim 3, wherein the moving speed of the coater is 3 mm / sec or more and 20 mm / sec or less.

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