KR101701670B1 - Perovskite solar cells containing N-type semiconductors modified with oxygen and halogen atoms, and fabricating method thereof - Google Patents

Abstract

The present invention relates to a perovskite solar cell having an N-type semiconductor modified with oxygen and halogen atom. More particularly, a recombination blocking agent composed of oxygen and halogen atom is adsorbed on the surface of an N-type semiconductor, thereby preventing interface recombination between N-type semiconductor and hole transport agent and improving the photoelectric conversion efficiency of a solar cell.

Description

TECHNICAL FIELD [0001] The present invention relates to a perovskite solar cell having an N-type semiconductor modified with oxygen and a halogen atom, and a perovskite solar cell having a perovskite solar cell containing N-type semiconductors modified with oxygen and halogen atoms,

The present invention relates to a perovskite solar cell having an N-type semiconductor modified with oxygen and a halogen atom, and more particularly to a perovskite solar cell having an N-type semiconductor-hole transporting material by adsorbing a recombination blocking agent composed of oxygen and halogen atoms on the surface of the N- And an n-type semiconductor modified with oxygen and halogen atoms capable of improving the efficiency of a solar cell by preventing interface recombination between the n-type semiconductor and the n-type semiconductor, and a method for manufacturing the same.

Solar Cells (Photovoltaic Cells) are a key component of photovoltaic power generation that convert sunlight directly into electricity and are now widely used for power supply from space to homes. In the early days when the solar cell was first made, it was mainly used for space use. However, since the 1970s, when it was undergoing two oil fluctuations, it became possible to use it as a ground power source. It began to be used as a dragon. Recently, it has been used in aeronautical, meteorological and telecommunication fields.

   Although such a solar cell mainly uses silicon semiconductor, there is a problem that the cost of power generation is high due to the raw material cost of a high purity (6N to 9N) silicon semiconductor and the complexity of the manufacturing process of the solar cell using the same. In other words, it is 3 to 10 times higher than the conventional unit price of fossil fuel, so it is limited by the government subsidy policy. For this reason, research and development of silicon-free solar cells have been promoted. In the 1990s, Dye-sensitized solar cells (DSSC) using organic semiconductor materials and polymer solar cells using conductive polymers Solar Cell: PSC) has started to be studied in earnest. Although organic semiconductor-based solar cells such as DSSC and PSC have not reached commercialization stage despite the efforts of academia and industry, the emergence of perovskite solar cell, which recently combines the merits of DSSC and PSC The expectations for next-generation solar cells are rising.

   Perovskite solar cells are fusion solar cells of conventional DSSC and PSC. They do not use liquid electrolyte like DSSC and have high reliability. They are solar cells that can be highly efficient due to optical superiority of perovskite. , Material improvement and structural improvement have been continuously improving efficiency. The structure of such a perovskite solar cell is shown in Fig. Referring to FIG. 1, a perovskite solar cell includes a substrate, a first electrode, a blocking layer, a photoactive layer composed of an N-type semiconductor (metal oxide) and a P-type semiconductor (perovskite) , And a second electrode. The operation principle of such a perovskite solar cell is as follows.

The perovskite compounds excited by sunlight inject electrons into the conduction band of an N-type semiconductor (mainly metal oxide), and the injected electrons pass through the N-type semiconductor and the blocking layer and are collected on the first electrode, Circuit. If there is no blocking layer, all electrons reaching the first electrode can not be transferred to the external circuit. That is, in the absence of the blocking layer, the upper surface of the first electrode is mostly in contact with the N-type semiconductor, but a portion of the electrons reaching the first electrode is not transmitted to the external circuit. (HTM) and is lost. This phenomenon is referred to as a first electrode-hole transport interface recombination (hereinafter referred to as a first recombination phenomenon), which causes a decrease in photoelectric conversion efficiency. In order to minimize the recombination phenomenon of the interface between the first electrode and the hole transport agent, a blocking layer is formed as shown in FIG. 1 to prevent direct contact between the first electrode and the hole transport agent. On the other hand, the electrons reach the second electrode via the external circuit, and then transfer electrons to the P-type semiconductor through the hole transport layer, thereby completing the solar cell operation.

Currently, the commercialization of perovskite solar cells is accelerated, and in order to replace conventional high-priced silicon solar cells, improvement of photoelectric conversion efficiency should be preceded. In the perovskite solar cell shown in Fig. 1, the perovskite compound which is the p-type semiconductor does not exist over the entire surface of the n-type semiconductor. Therefore, a part of the surface of the N-type semiconductor exists in direct contact with the hole transporting agent. As a result, electrons injected into the N-type semiconductor react with the hole transporting agent and disappear. This phenomenon is referred to as an N-type semiconductor-hole transport interface recombination (hereinafter referred to as a second recombination phenomenon), which is a problem of lowering the efficiency of a perovskite solar cell.

Korean Patent Publication No. 10-2015-0124412 Korean Patent Publication No. 10-2015-0124413 Korean Patent No. 10-1492022

G.S. Han et al, J. Mater. Chem. A, 3, 9160-9164 (2015) D. H. Cao, APL MATERIALS, 2, 091101-1 ~ 091101-7 (2014)

The present invention has been conceived to improve efficiency of a solar cell by preventing a second recombination phenomenon between a conventional N-type semiconductor and a hole transport agent, and is characterized in that five or more unshared electron pairs are covalently bonded with oxygen and halogen atoms, The blocking agent is adsorbed on the surface of the N-type semiconductor to obtain the modified N-type semiconductor. By using the modified N-type semiconductor, direct contact between the N-type semiconductor and the hole transporting agent is prevented to prevent the second recombination phenomenon, And an N-type semiconductor modified with oxygen and a halogen atom capable of improving the performance of a perovskite solar cell and a method of manufacturing the same.

Hereinafter, the constituent elements and the manufacturing method of the present invention will be described in detail.

≪ Substrate / First electrode preparation and cleaning >

The first electrode formed on the substrate is immersed in acetone, ethanol, distilled water or a mixed solution thereof, followed by ultrasonic cleaning. Any substrate that is optically transparent, such as glass or plastic, may be used. The first electrode is FTO (F-doped tin oxide) , ITO (In-doped tin oxide), IZO (In-doped zinc oxide), ZnO-Ga 2 O 3, ZnO-Al 2 O 3, SnO 2 - Transparent and conductive transparent electrodes such as Sb ₂ O ₃ can be used.

≪ Blocking layer Formation>

As described above, the blocking layer is formed to improve the efficiency by preventing the first recombination (interface recombination of the first electrode and the hole transporting material), and a material such as TiO ₂ or ZnO is used as the material for the blocking layer For example. For example, if the cleaned substrate / first electrode is immersed in a precursor solution (TiCl ₄ ) at a concentration of 40 mM and left at 70 ° C for 30 minutes, a titanium oxychloride is formed on the surface of the first electrode , Washed with distilled water and ethanol, and then fired at a high temperature (450 to 500 ° C.) to form a TiO ₂ blocking layer. Another method is to dissolve a Ti precursor such as Ti (IV) bis (ethylacetoacetato) -diisopropoxide or titanium (IV) isopropoxide in a solvent, and then spin coating or spray coating to form a TiO ₂ blocking layer . On the other hand, in case of ZnO, ZnO blocking layer can be formed by dissolving zinc acetate dihydrate and ethanolamine in a solvent (2-methoxy ethanol) and then coating and drying on the first electrode by spin coating or the like. Since the blocking layer is formed for the purpose of improving the photoelectric conversion efficiency of the perovskite solar cell, there is no problem in the operation of the solar cell without the blocking layer.

< Blocking layer  Upper N-type semiconductor layer Formation>

A paste containing N-type semiconductor nanoparticles is coated on the blocking layer to form a thin film, followed by heat treatment (450 to 550 DEG C) in air or oxygen atmosphere for about 30 to 60 minutes to form an N-type A semiconductor layer can be formed. In some cases, the N-type semiconductor layer is formed of TiCl ₄ (450 ~ 550 ° C) to fill the pores between the N-type semiconductor particles to induce additional efficiency improvement. The material for the N-type semiconductor layer may include a metal oxide selected from the group consisting of TiO ₂ , Al ₂ O ₃ , SnO ₂ , ZnO, WO ₃ , Nb ₂ O ₅ , TiSrO ₃ , ZrO ₂ , But may not be limited thereto. As a method of coating the N-type semiconductor on the blocking layer, a doctor blade coating, a screen printing, a flexography method, a gravure printing method, or the like may be used.

< N-type semiconductor  By adsorption of recombination blocking agent on the surface N-type semiconductor Surface modification>

In order to adsorb a recombination blocking agent composed of oxygen and halogen atoms on the surface of the N-type semiconductor of the metal oxide system, in the present invention, a deposition solution is prepared by adding a recombination blocking agent to a solvent, and a substrate on which the N- The recombination blocking agent is adsorbed on the N type semiconductor surface. The hydroxyl groups present on the surface of the N-type semiconductor of the metal oxide system and the anionic functional groups of the recombination blocking agent can adsorb the recombination blocking agent to the surface of the N-type semiconductor of the metal oxide system by chemisorption and / or physisorption have. In this case, the immersion time is suitably about 0.1 minute to 24 hours. After the immersion, the substrate is washed with distilled water and a solvent of alcohols, dried at a temperature of about 60 to 70 ° C for about 10 to 20 minutes, It is possible to adsorb the recombination blocking agent on the surface of the oxide (N-type semiconductor).

The recombination blocking agent of the present invention is characterized in that oxygen and halogen atoms are linked by a covalent bond, and at least five unshared electron pairs are contained in the recombination blocking agent molecule. Preferably 5 to 8 non-covalent electron pairs in the molecule. Examples of such a recombination blocking agent include metal salts of HClO ₃ and HClO ₃ [LiClO ₃ , CsClO ₃ , Ca (ClO ₃ ) ₂ , Cr (ClO ₃ ) ₂ and the like], amine salts of HClO ₃ [NH ₄ ClO ₃ , NH C ₂ H _{5) 3} ClO ₃ -, HClO _4, a metal salt _{[NaClO 4, FrClO 4, Sr} (ClO 4) 2, Mo (ClO 4) 2 , etc.], salts of HClO ₄ of HClO ₄ [NH ₄ ClO _{4 , NH (C 2 H 5)} 3 ClO 4], HClO 2, metal salts _{[NaClO 2, FrClO 2, Sr} (ClO 2) 2, Mo (ClO 2) 2 , etc.], salts of HClO ₂ of HClO ₂ [NH _{4 ClO 2, NH (C 4} H 9) 3 ClO 2], HClO, of HClO metal salt [NaClO, FrClO, Sr (ClO ) 2, Mo (ClO) 2 , etc.], salts of HClO [NH ₄ ClO, NH _{(C 3 H 7) 3 ClO} ] and chlorinated compounds, HBrO _3, metal salt _{[LiBrO 3, CsBrO 3, Ca} (BrO 3) 2, Cr (BrO 3) 2 , etc.], salts of HBrO ₃ of HBrO ₃ as [ _{NH 4 BrO 3, NH (C} 2 H 5) 3BrO 3], HBrO 4, HBrO ₄ metal salt _{[NaBrO 4, FrBrO 4, Sr} (BrO 4) 2, Mo (BrO 4) 2 , etc.], the HBrO _4-amine salt _{[NH 4 BrO 4, NH (} C 2 H 5) 3 BrO 4], HBrO 2, metal salts of _{HBrO 2 [NaBrO 2, FrBrO 2} , Sr (BrO 2) 2, Mo (BrO 2) 2 , etc.], HBrO ₂ of the amine _{[NH 4 BrO 2, NH (} C 4 H 9) 3 BrO 2], HBrO, of HBrO metal salt [NaBrO, FrBrO, Sr (BrO ) 2, Mo (BrO) 2 , etc.], salts of HBrO [NH ₄ BrO , NH for _{(C 3 H 7) 3 BrO} ] and like bromine-based compounds, HIO _3, HIO ₃ of metal salt _{[LiIO 3, CsIO 3, Ca} (IO 3) 2, Cr (IO 3) 2 , etc.], HIO ₃ salt _{[NH 4 IO 3, NH (} C 2 H 5) 3 IO 3], HIO 4, HIO 4 of metal salt _{[NaIO 4, FrIO 4, Sr} (IO 4) 2, Mo (IO 4) 2 , etc.], amine salts of _{HIO 4 [NH 4 IO 4,} NH (C 2 H 5) 3 IO 4], HIO 2, metal salts of _{HIO 2 [NaIO 2, FrIO 2} , Sr (IO 2) 2, Mo (IO 2) 2 (NaIO, FrIO, Sr (IO) ₂ , Mo (IO) _2, etc.) of the amine salts of NHIO ₂ [NH ₄ IO ₂ , NH (C ₄ H ₉ ) ₃ IO ₂ ], HIO, (LiFO ₃ , CsFO ₃ , Ca (FO ₃ ) ₂ , Cr (FO ₃ ), and the like) of an iodine compound, HFO ₃ and HFO ₃ as well as an amine salt of HIO [NH ₄ IO, NH (C ₃ H ₇ ) ₃ IO] ) _2], salts of _{HFO 3 [NH 4 FO 3,} NH (C 2 H 5) 3 FO 3], HFO 4, metal salts of _{HFO 4 [NaFO 4, FrFO 4} , Sr (FO 4) 2, Mo (FO ₄ ) ₂ ], the amine salt of HFO ₄ [NH ₄ FO ₄ , NH (C ₂ H ₅ ) ₃ FO ₄ ], HFO ₂ , HFO ₂ Of metal salt _{[NaFO 2, FrFO 2, Sr} (FO 2) 2, Mo (FO 2) 2 , etc.], salts of _{HFO 2 [NH 4 FO 2,} NH (C 4 H 9) 3 FO 2], HFO, A fluorine-based compound such as a metal salt of HFO (NaFO, FrFO, Sr (FO) ₂ , Mo (FO) ₂ etc.) and an amine salt of HFO [NH ₄ FO, NH (C ₃ H ₇ ) ₃ FO] Or may be used in plural.

Examples of the solvent include tertiary butyl alcohol, acetonitrile, tetrahydrofuran, ethanol, isopropyl alcohol, methanol, acetone, Propanol, methylethylketone, butylalcohol, water, formamide, N-methylformamide, N, N-dimethylformamide (N N-dimethylformamide, acetamide, N-methylacetamide, N, N-dimethylacetamide, N-methylpropionamide, 2-pyrrolidone, N-methyl pyrrolidone, methyl sulfoxide, dimethyl sulfoxide, sulfolane, diphenyl sulfone, ) May be used singly or in plural, and the present invention is not limited thereto It is not.

  FIG. 2 is a conceptual view illustrating the role of the recombination blocking agent according to the present invention. The recombination blocking agent is adsorbed on the surface of a metal oxide (N-type semiconductor) to prevent direct contact with a hole transporting material (HTM) It is possible to prevent recombination (N-type semiconductor-hole transport interface recombination) phenomenon. The recombination blocking agent according to the present invention has oxygen and halogen atoms covalently bonded in the molecule thereof and has a large number of non-covalent electron pairs in oxygen and halogen atoms as shown in Fig. 2, So that the second recombination phenomenon can be prevented. As described above, the recombination blocking agent according to the present invention prevents (2) a recombination phenomenon by preventing direct contact between the N-type semiconductor and the hole transporting material, (2) a non-covalent electron pair Or more) and the electrons injected into the N-type semiconductor act in addition to the effect of preventing the second recombination phenomenon. (3) Since the recombination blocking agent made of oxygen and halogen atoms of the present invention is an insulating material, the electron blocking effect is much larger, and (4) the semiconductor layer can be adsorbed onto the surface of the semiconductor layer by a simple deposition process.

< N-type semiconductor  On the surface P-type semiconductor  Junction>

In order to operate as a solar cell, an N-type semiconductor and a P-type semiconductor must be bonded, and a P-type semiconductor must be bonded to the surface of the N-type semiconductor on which the recombination blocking agent is adsorbed, as shown in FIG. The p-type semiconductor absorbs light, and electrons are transferred from the ground state to the excited state to form an electron-hole pair. The electrons in the excited state are injected into the conduction band of the n-type semiconductor, So that an electromotive force is generated.

As the P-type semiconductor material, a compound represented by RMX ₃ having a well-known perovskite crystal structure can be used. Wherein R is ^{_{CnH 2n + 1 NH 3 + (}} n is an integer from 1 to ^{_{9), NH 4 +, HC}} (NH 2) 2 +, CS +, NF 4 +, NCl 4 +, PF 4 +, PCl 4 + ^{_{, CH 3 PH 3 +, CH}} 3 AsH 3 +, CH 3 SbH 3 +, PH 4 +, AsH 4 +, SbH 4 + , and means a monovalent cation selected from the group consisting of a combination thereof, and M is Means a divalent metal cation selected from the group consisting of Pb ₂ ⁺ , Sn ₂ ⁺ , Ge ₂ ^+, and combinations thereof, and X means a halogen anion such as F ^- , Cl ^- , Br ^- , or I ^- .

A variety of methods for bonding a P-type semiconductor to an N-type semiconductor surface are known. Hereinafter, a case where R is an alkylammonium ion will be briefly described as follows. (Spin coating, dip coating, etc.) on the N-type semiconductor, followed by heat treatment (40 to 300 ° C) to form a PN junction . Alternatively, a method may be used in which an alkylammonium halide solution and a metal halide solution are separately prepared, a substrate including the N-type semiconductor is successively deposited or spin coated, and then heat-treated to form a P-N junction. In addition to the above methods, a method of vacuum deposition of an alkylammonium halide precursor and a metal halide precursor, and a method of vacuum depositing a finally synthesized perovskite material are possible. When a solution of the precursor or perovskite material is prepared and the P-N bonding process is performed, γ-butyrolactone, dimethylsulfoxide, dimethylformamide, N-methyl-2-pyrrolidone and dimethylacetamide may be used.

As described above, the method of bonding the P-type semiconductor to the adsorption of the recombination blocking agent on the surface of the N-type semiconductor has been described, but the method is not limited thereto. The above method is a method of first adsorbing a recombination blocking agent and bonding a P-type semiconductor, but there is no problem in the operation of a solar cell even if the order is changed. That is, it is also possible to bond the p-type semiconductor first by the above-described method and adsorb the recombination blocking agent.

< Hole transport layer  Formation>

The P-type semiconductor, perovskite, absorbs light to form electron-hole pairs, and the hole transport layer serves to transfer the generated holes to the second electrode. As the material constituting the hole transporting layer, a compound having a capability of transporting holes and having not only a property of blocking electrons but also an ability of forming a thin film is preferable. Specifically, a low molecular weight compound such as a phthalocyanine compound, an indigo, a thioindigo compound, a melocyanine compound, a cyanine compound or an arylamine compound, a thiophene polymer, a polymer having an arylamine group, Material is possible. Typical examples of the low-molecular compound include Spiro-OMeTAD [2,2 ', 7,7'-tetrakis- (N, N-di-4-methoxyphenylamino) -9,9'-spirobifluorene]. Poly (3,4-ethylenedioxythiophene): poly (4-styrene sulfonate)], G-PEDOT [poly (3,4-ethylenedioxythiophene) poly (4-styrene sulfonate), PANI: polyaniline (camphor sulfonic acid), PDBT (poly (4,4'-dimethoxy bithophene) (Hexylthiophene) (P3HT), (poly [2,1,3-benzothiadiazole-4,7-diyl [ 3,4-b '] dithiophene-2,6-diyl]] (PCPDTBT), (poly [[9- (1-octylnonyl) -9H- carbazole- 2,5-thiophenediyl]) (PCDTBT), or poly (triarylamine) (PTAA). Examples of the inorganic material include, but are not limited to, MoO ₃ , V ₂ O ₅ , NiO, WO ₃ , CuI, CuSCN and the like. The low- Yes , But they may additionally contain dopants such as 4-tertbutylpyridine, lithium bis (trifluoromethanesulfonyl) imide [LiN (CF ₃ SO ₂ ) ₂ ], butylmethyl imidazolium iodide, methyl-imidazolium iodide, and lithium iodide, which can be used singly or in combination.

The hole transport layer may be formed by a spin coating method, a spray coating method, a screen printing method, a bar coating method, a doctor blade coating method, or the like, or may be formed by thermal deposition or sputtering under vacuum . The thickness of the hole transport layer is preferably about 5 to 300 nm.

&Lt; Formation of second electrode &

The second electrode formed on the hole transport layer performs a role of collecting holes (that is, a function of receiving holes from the hole transport layer), has high electrical conductivity, is capable of ohmic junction with the hole transport layer, Should be excellent. As materials for the second electrode, silver (Ag), platinum (Pt), tungsten (W), copper (Cu), molybdenum (Mo), gold (Au) (Pd), In, ruthenium (Rh), iridium (Ir), osmium (Os), conductive carbon and conductive polymer. . Such a second electrode may be formed by a DC sputtering method, thermal evaporation or alternatively by a wet method such as chemical vapor deposition (CVD), atomic layer deposition (ALD), electroplating and various printing techniques, .

Since the perovskite solar cell according to the present invention may be deteriorated by moisture and oxygen during operation, it is necessary to block each layer formed from the atmosphere. First, attach a moisture absorbent that absorbs moisture to the center of the protective cap made of glass or metal, and dispense sealing material at the edge. Next, the prepared device (substrate / first electrode / N type semiconductor: P type semiconductor: hole transport agent / second electrode) is disposed on the top of the dispensed sealing material, and then the sealing material is cured by applying UV or heat. If the sealing material is cured using UV, it is necessary to prevent UV light from entering the photoactive layer, since the photoactive layer may be deteriorated by UV. In addition, a method of forming a multilayer thin film under vacuum may be used for the sealing process. These sealing processes have already been well established in the organic electroluminescent device industry. In the perovskite solar cell of the present invention, which is realized by the above-described structure and manufacturing process, a grid electrode may be further formed on the first electrode and / or the second electrode. The grid electrode mainly consists of a metal contact layer and can be formed through an electron beam system or another method, and mainly Ni, Al, Ag or the like can be used. Further, an anti-reflection layer may be additionally formed inside or outside the transparent substrate. In general, silicon nitride (SiNx) is used as an antireflection layer which functions to further increase the efficiency by reducing the reflection loss of sunlight incident on the solar cell. The thickness of the antireflection layer is preferably 600 to 600 nm by electron beam evaporation or chemical vapor deposition (CVD) 1000 &lt; / RTI &gt;

The recombination blocking agent composed of oxygen and halogen atoms according to the present invention can prevent the second recombination phenomenon by preventing the direct contact between the N-type semiconductor and the hole transport agent, thereby improving the efficiency of the solar cell. Second, The second recombination phenomenon is further prevented by the action of the repulsive force between at least 5 or more, preferably 5 to 8 non-covalent electron pairs contained in the atoms and the electrons injected into the N-type semiconductor. Thirdly, Since the recombination blocking agent made of a halogen atom is an insulating material, the electron blocking effect is much greater. Fourth, the adsorption can be performed on the surface of the semiconductor layer by a simple deposition process.

1 is a structural view of a perovskite solar cell,
2 is a conceptual diagram for preventing the recombination blocking agent adsorbed on the surface of the N-type semiconductor to prevent the second recombination phenomenon,
3 is a graph showing current-voltage characteristics of a solar cell according to Comparative Example 1,
4 is a graph showing current-voltage characteristics of a solar cell fabricated according to Example 1 of the present invention,
5 is a graph of dark current according to voltages of the solar cells according to Comparative Examples 1 and 2.

Hereinafter, the perovskite solar cell of the present invention and its implementation method will be described in detail by way of examples. However, the present invention is not limited to the following examples.

Comparative Example  One

First, 0.15 M titanium diisopropoxide bis (acetylacetonate) solution (solvent: 1-butanol) was prepared to form a blocking layer, and then spin-coated on the cleaned FTO substrate. This was repeated three times and then heat-treated at 500 ° C for 20 minutes to form a blocking layer of TiO ₂ component. Subsequently, TiO ₂ paste ( _{trade name} : Solaronix, TiO ₂ particle size: 20 nm) was diluted with ethanol and coated on the upper side of the blocking layer by spin coating (3000 rpm, 30 s) Type semiconductor layer. A 1.0 M PbI ₂ solution (solvent: dimethylformamide) was spin-coated on the substrate on which TiO _{2, which} is an N-type semiconductor, was formed and then dried. Then, a CH ₃ NH ₃ I solution (10 mg / mL, solvent: 2-propanol) To deposit a perovskite compound CH ₃ NH ₃ PbI ₃ (P type semiconductor) on the surface of TiO ₂ . After dissolving the spiro-OMeTAD (0.085M), tert -butylpyridine, LiN (CF 3 SO 2) 2 in chlorobenzene solvent to form a hole transport layer by spin coating and dried to form a hole transport layer. A perovskite solar cell was fabricated by forming Ag as a second electrode with a thickness of 100 nm on the hole transport layer by a thermal deposition method. The photoelectric conversion efficiency of the completed perovskite solar cell was measured using a solar simulator and IV measurement equipment. Figure 3 shows the IV curves obtained after irradiating the device with light of AM 1.5 (100 mW / cm ² ) to the manufactured solar cell device. V _OC (open circuit voltage) is 0.924 V , J _SC circuit current density was 18.79 mA / cm ^2, and the fill factor was 69.8%, indicating a photoelectric conversion efficiency of 12.12%.

Example  One

Except that the substrate on which the N-type semiconductor (TiO ₂ ) was formed was immersed in an aqueous solution of 100 mM for 20 minutes to add a step of adsorbing the recombination blocking agent (LiBrO ₃ ) on the surface of the TiO ₂ in the solar cell manufacturing process shown in Comparative Example 1 A perovskite solar cell was prepared in the same manner as in Comparative Example 1 except that all conditions were changed. The photovoltaic conversion efficiency was measured by the same equipment and method. V _OC was 1.00 V , J _SC was 20.23 mA / cm ^2, and the fill factor was 70.1%, which showed a photoelectric conversion efficiency of 14.18%, which is shown in FIG. Compared with the comparative example 1, the V _OC and J _SC were greatly increased. This indicates that the recombination blocking agent adsorbed on the TiO ₂ surface not only prevented the direct contact with the hole transport agent but also the eight non-covalent electron pairs This is because the second recombination phenomenon is reduced by the repulsive force between the electrons transferred from the p-type semiconductor (CH ₃ NH ₃ PbI ₃ ) to TiO ₂ .

Example  2

In the solar cell manufacturing process shown in Comparative Example 1, the substrate on which the N type semiconductor (TiO ₂ ) was formed was immersed in an aqueous solution of 50 mM NH ₄ ClO ₄ for 30 minutes to adsorb the recombination blocking agent (NH ₄ ClO ₄ ) on the surface of the TiO ₂ A perovskite solar cell was manufactured in the same manner as in Comparative Example 1 except that the process was added. The photovoltaic conversion efficiency was measured by the same equipment and method. V _OC was 0.982 V , J _SC was 21.01 mA / cm ^2, and the fill factor was 69.9%, indicating a photoelectric conversion efficiency of 14.42%. Similar to the results of Example 1, V _OC and J _SC were greatly increased compared to Comparative Example 1, indicating that the recombination blocking agent (NH ₄ ClO ₄ ) adsorbed on the TiO ₂ surface prevented direct contact with the hole transport agent This is because the second recombination phenomenon is reduced by the repulsive force between the eight non-covalent electron pairs present in the recombination blocking agent and the electrons transferred from the P type semiconductor (CH ₃ NH ₃ PbI ₃ ) to TiO ₂ . In order to analyze the reason why the recombination blocking agent of the present invention is adsorbed on the surface of the N-type semiconductor (TiO ₂ ), the dark current was measured using the solar cell manufactured in the process of Comparative Example 1 and Example 2 The results are shown in Fig. As can be seen from FIG. 5, the dark current of the solar cell according to Example 2 of the present invention was smaller than that of the solar cell according to Comparative Example 1. This is because the recombination blocking agent is adsorbed on the surface of the N type semiconductor (TiO ₂ ), so that the second recombination shape is prevented and the dark current is reduced. As a result, V _OC and J _SC are improved.

Example  3

From the comparison a solar cell manufacturing process presented in Example 1, N-type semiconductor (TiO ₂₎ is NaIO ₂ solution of 30mM substrate formed rejoins the TiO ₂ surface by immersion for 30 minutes (ethanol and water mixed solvent) blockers (NaIO ₂₎ A perovskite solar cell was manufactured in the same manner as in Comparative Example 1 except that all of the conditions were changed. The photovoltaic conversion efficiency was measured by the same equipment and method. V _OC was 0.945 V , J _SC was 20.34 mA / cm ^2, and the fill factor was 70.2%, indicating a photoelectric conversion efficiency of 13.49%.

Example  4

In the solar cell manufacturing process shown in Comparative Example 1, the solar cell was manufactured by the following two processes. First, a ZnO sol was prepared by mixing 1 g of zinc acetate dihydrate, 0.28 g of ethanolamine, and 10 mL of 2-methoxy ethanol, and then spin coating and heat treatment were performed on the cleaned FTO substrate to form a blocking layer. ZnO was used instead of TiO _{2 as a} blocking layer material. Second, N-type semiconductor (TiO ₂₎ a Mo (BrO ₄₎ in 200mM a substrate formed of ₂ solution (dimethyl formamide and water mixed solvent) recombination blockers TiO ₂ surface by immersion for 30 minutes [Mo (BrO _{4) 2]} Was added. Thus, a perovskite solar cell was produced in the same manner as in Comparative Example 1 except for the above two process conditions. The photovoltaic conversion efficiency was measured by the same equipment and method. V _OC was 0.107 V , J _SC was 21.09 mA / cm ^2, and the fill factor was 70.6%, indicating a photoelectric conversion efficiency of 15.93%.

Example  5

In the solar cell manufacturing process shown in Comparative Example 1, the substrate on which the N type semiconductor (TiO ₂ ) was formed was immersed in an aqueous solution of 150 mM HFO ₃ for 1 minute to form TiO ₂ A perovskite solar cell was manufactured in the same manner as in Comparative Example 1 except that a process of adsorbing a recombination blocking agent (HFO ₃ ) on the surface was added. The photovoltaic conversion efficiency was measured by the same equipment and method. V _OC is 0.988 V , J _SC is 19.98 mA / cm ² And a fill factor of 70.8%, indicating a photoelectric conversion efficiency of 13.98%.

Example  6

A perovskite solar cell was manufactured in the same manner as in Example 1, except that the N-type semiconductor was changed to Al ₂ O ₃ in the solar cell manufacturing process shown in Example 1. The photovoltaic conversion efficiency was measured by the same equipment and method. V _OC was 1.04 V , J _SC was 20.88 mA / cm ^{2, and the} fill factor was 69.8%, indicating a photoelectric conversion efficiency of 15.16%.

Example  7

A perovskite solar cell was manufactured in the same manner as in Example 1, except that the N-type semiconductor was changed to ZrO ₂ in the solar cell manufacturing process shown in Example 1. The photovoltaic conversion efficiency was measured by the same equipment and method. V _OC is 0.96 V , J _SC is 19.92 mA / cm ² And a fill factor of 70.8%, indicating a photoelectric conversion efficiency of 13.54%.

Claims (12)

A first electrode formed on the substrate, a blocking layer formed on the first electrode, a photoactive layer formed on the blocking layer, a hole transport layer formed on the photoactive layer, and a second electrode formed on the hole transport layer Wherein the photoactive layer is an N-type semiconductor, a recombination blocking agent adsorbed on the surface of the N-type semiconductor and composed of oxygen and halogen atoms and having five or more non-covalent electron pairs, a P- A perovskite solar cell comprising an N-type semiconductor modified with oxygen and a halogen atom.
The method according to claim 1,
The recombination blockers of HClO _3, HClO ₃ of the metal salt, HClO ₃ of the amine salt, HClO _4, HClO ₄ of the metal salt, HClO ₄ salt, HClO _2, HClO ₂ of the metal salts, amine salts, HClO, HClO of HClO ₂ of Chlorinated compounds such as metal salts and amine salts of HClO; HBrO _3, amine salt of HBrO ₃ metal salts, HBrO ₃ of, HBrO _4, of HBrO ₄ metal salt, HBrO ₄ of salt, HBrO _2, the HBrO2 metal salts, amine salts of HBrO _2, HBrO, of HBrO metal salts of HBrO amine A bromine-based compound such as a salt; Of HIO _3, HIO ₃ metal salts, HIO ₃ of the amine salt, HIO _4, HIO ₄ of the metal salt, HIO ₄ of salt, HIO _2, HIO ₂ of the metal salt, HIO ₂ salt, HIO, the HIO metal salt, HIO of Iodine compounds such as amine salts; Of HFO _3, HFO ₃ metal salts, HFO ₃ of the amine salt, HFO _4, HFO ₄ of the metal salt, HFO ₄ of salt, HFO _2, HFO ₂ of the metal salt, HFO ₂ salt, HFO, the HFO metal salt, HFO of Wherein the perovskite type solar cell comprises an N-type semiconductor modified with oxygen and a halogen atom.
The method according to claim 1,
Wherein the substrate is selected from optically transparent glass and plastic. &Lt; RTI ID = 0.0 &gt; 11. &lt; / RTI &gt; A perovskite solar cell having an N-type semiconductor modified with oxygen and halogen atoms.
The method according to claim 1,
The first electrode FTO (F-doped tin oxide) , ITO (In-doped tin oxide), IZO (In-doped zinc oxide), ZnO-Ga 2 O 3, ZnO-Al 2 O 3, SnO 2 -Sb ₂ O ₃ and characterized in that the transparent and conductive, transparent electrodes such as, Fe with an oxygen atom and a halogen-modified N-type semiconductor perovskite solar cells.
The method according to claim 1,
Wherein the blocking layer is selected from the group consisting of TiO ₂ and ZnO, singly or in combination, and the N-type semiconductor modified with oxygen and halogen atoms. The method according to claim 1,
Wherein the material for the N-type semiconductor is selected from the group consisting of TiO ₂ , Al ₂ O ₃ , SnO ₂ , ZnO, WO ₃ , Nb ₂ O ₅ , TiSrO ₃ and ZrO ₂ , A perovskite solar cell having an N - type semiconductor.
The method according to claim 1,
The material for the hole transport layer is Spiro-OMeTAD (2,2 ', 7,7'-tetrakis- (N, N-di-4-methoxyphenylamino) -9,9'- spirobifluorene], PEDOT: 4-ethylenedioxythiophene: poly (4-styrene sulfonate)], G-PEDOT [poly (4-ethylenedioxythiophene): polyglycol (glycerol)], PANI: (styrene sulfonate), PANI: polyaniline, camphor sulfonic acid, PDBT, poly (3-hexylthiophene) (P3HT) Synthesis of 3-benzothiadiazole-4,7-diyl [4,4-bis (2-ethylhexyl-4H- cyclopenta [2,1- b: 3,4- b '] dithiophene- ]] (PCPDTBT), (poly [[9- (1-octylnonyl) -9H-carbazole-2,7-diyl] -2,5-thiophenediyl-2,1,3-benzothiadiazole- (PCDTBT) or poly (triarylamine) (PTAA), MoO ₃ , V ₂ O ₅ , NiO, WO ₃ , CuI, CuSCN, , Characterized in that a perovskite solar cell having an N-type semiconductor modified with oxygen and a halogen atom, . 8. The method of claim 1 or 7,
The hole transport layer may further include a dopant, and the dopant may include 4-tertbutylpyridine, lithium bis (trifluoromethanesulfonyl) imide [LiN (CF ₃ SO ₂ ) ₂ ]), butylmethyl imidazolium iodide, 3-propyl-1-methyl-imidazolium iodide, Wherein the perovskite solar cell has an N-type semiconductor modified with oxygen and a halogen atom, which is selected singly or in plurality from lithium iodide.
The method according to claim 1,
It is the P-type semiconductor RMX ₃ [wherein R is ^{_{CnH 2n + 1 NH 3 + (}} n is an integer from 1 to ^{_{9), NH 4 +, HC}} (NH 2) 2 +, CS +, NF 4 +, NCl 4 + , PF ₄ ⁺ , PCl ₄ ⁺ , CH ₃ PH ₃ ⁺ , CH ₃ AsH ₃ ⁺ , CH ₃ SbH ₃ ⁺ , PH ₄ ⁺ , AsH ₄ ⁺ , SbH ₄ ⁺ And M is a divalent metal cation selected from the group consisting of Pb ₂ ⁺ , Sn ₂ ⁺ , Ge ₂ ^+, and combinations thereof, and X represents F ^- , Cl ^- , Br ^- , I ^- And the same halogen anion.] The perovskite solar cell has an N-type semiconductor modified with oxygen and a halogen atom. The method according to claim 1,
The second electrode may be at least one selected from the group consisting of Ag, Pt, W, Cu, Mo, Au, Ni, Wherein at least one selected from the group consisting of ruthenium (Ru), palladium (Pd), rhodium (Rh), iridium (Ir), osmium (Os), conductive carbon, A perovskite solar cell. Forming a first electrode over the substrate;
Forming a blocking layer on the first electrode;
Forming a photoactive layer over the blocking layer;
Forming a hole transport layer on the photoactive layer;
And forming a second electrode on the hole transport layer,
Wherein the photoactive layer comprises an N-type semiconductor layer;
Adsorbing a recombination blocking agent composed of oxygen and halogen atoms on the surface of the N-type semiconductor layer and having five or more non-covalent electron pairs; And
A method of manufacturing a perovskite solar cell having an N-type semiconductor modified with oxygen and a halogen atom, the method comprising: bonding an N-type semiconductor and a P-type semiconductor. 12. The method of claim 11,
The recombination blockers of HClO _3, HClO ₃ of the metal salt, HClO ₃ of the amine salt, HClO _4, HClO ₄ of the metal salt, HClO ₄ salt, HClO _2, HClO ₂ of the metal salts, amine salts, HClO, HClO of HClO ₂ of Chlorinated compounds such as metal salts and amine salts of HClO; HBrO _3, amine salt of HBrO ₃ metal salts, HBrO ₃ of, HBrO _4, of HBrO ₄ metal salt, HBrO ₄ of salt, HBrO _2, the HBrO2 metal salts, amine salts of HBrO _2, HBrO, of HBrO metal salts of HBrO amine A bromine-based compound such as a salt; Of HIO _3, HIO ₃ metal salts, HIO ₃ of the amine salt, HIO _4, HIO ₄ of the metal salt, HIO ₄ of salt, HIO _2, HIO ₂ of the metal salt, HIO ₂ salt, HIO, the HIO metal salt, HIO of Iodine compounds such as amine salts; Of HFO _3, HFO ₃ metal salts, HFO ₃ of the amine salt, HFO _4, HFO ₄ of the metal salt, HFO ₄ of salt, HFO _2, HFO ₂ of the metal salt, HFO ₂ salt, HFO, the HFO metal salt, HFO of Wherein the phosphorus-based compound is selected from the group consisting of a fluorine-based compound such as an amine salt, and an N-type semiconductor modified with oxygen and a halogen atom.

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