Passivation layer of perovskite solar cell and perovskite solar cell comprising same

Abstract

The present invention relates to a passivation layer of a perovskite solar cell and, more specifically, to: a passivation layer of a perovskite solar cell, capable of securing device stability by preventing penetration of moisture, oxygen, and the like, and thus being able to prevent a change in the lattice structure within the perovskite and minimize a decrease in photoelectric conversion efficiency over time; and a perovskite solar cell comprising same.

Description

Passivation layer of a perovskite solar cell and a perovskite solar cell including the same

[0001] The present invention relates to a passivation layer of a perovskite solar cell, and more specifically, to a passivation layer of a perovskite solar cell and a perovskite solar cell comprising the same.

[0002] In order to address the depletion of fossil fuels and the global environmental problems caused by their use, research on renewable and clean alternative energy sources such as solar, wind, and hydroelectric power is actively underway.

[0003] Among these, interest in solar cells, which directly convert sunlight into electrical energy, is increasing significantly. Here, a solar cell refers to a battery that generates current and voltage by utilizing the photovoltaic effect, which absorbs light energy from sunlight to generate electrons and holes.

[0004] Various methods for such solar cells are being proposed, and among them, solar cells utilizing perovskite material—known to have the same crystal structure as calcium titanium oxide (CaTiO3)—as the light-absorbing layer are gaining attention.

[0005] Perovskite solar cells are third-generation solar cells that combine silicon wafer-based technology and thin-film technology. Compared to other types of solar cells, they possess characteristics such as a high absorption coefficient, a variable band gap, and a rapidly increasing capacity. In addition, perovskite solar cells are superior to silicon solar cells in terms of cost, rigidity, weight, and efficiency.

[0006] Meanwhile, conventional perovskite solar cells were vulnerable to moisture and oxygen, which caused problems such as changes in the lattice structure within the perovskite and degradation of solar cell performance upon exposure to the atmosphere.

[0007]

[0008] Accordingly, there is an urgent need to develop methods to ensure the stability of perovskite solar cells by preventing the intrusion of moisture, oxygen, and other substances.

[0009] The present invention was devised to overcome the aforementioned problems and aims to provide a passivation layer for a perovskite solar cell and a perovskite solar cell including the same, which can prevent the penetration of moisture, oxygen, etc., thereby ensuring the stability of the device, preventing changes in the lattice structure within the perovskite, and minimizing the decrease in photoelectric conversion efficiency over time.

[0010] To solve the above-mentioned problem, the present invention provides a passivation layer of a perovskite solar cell comprising a compound comprising at least one of Al and Si and at least one of N and O, having a density of 1.4 to 2.6 g / cm³.

[0011] According to a preferred embodiment of the present invention, the passivation layer may have a density of 1.5 to 2.5 g / cm³.

[0012] In addition, the above passivation layer is AlO x , SiN x and SiO x It may include one or more of the following.

[0013] In addition, the passivation layer may have a refractive index of 1.65 or higher.

[0014] In addition, the above passivation layer is SiN x and SiO x It includes one or more of the above, and the refractive index may be 1.85 or higher.

[0015]

[0016] In addition, the present invention provides a perovskite solar cell comprising a first electrode, a hole transport layer (HTL) disposed on the first electrode, a photoactive layer disposed on the hole transport layer and having perovskite, an electron transport layer (ETL) disposed on the photoactive layer, a second electrode disposed on the electron transport layer, and the above-described passivation layer disposed on the second electrode.

[0017] According to a preferred embodiment of the present invention, a recombination layer may be further included between the first electrode and the hole transport layer.

[0018] In addition, an anti-reflection layer (AR layer) may be further included between the electron transport layer and the passivation layer.

[0019] In addition, the above perovskite solar cell has a water vapor transmission rate (WVTR) of 0.8 × 10⁻⁶ -3 ~ 1.2×10 -2 g / m 2 It could be a day.

[0020] The passivation layer of the perovskite solar cell of the present invention and the perovskite solar cell including the same can ensure the stability of the device by preventing the penetration of moisture, oxygen, etc., thereby preventing changes in the lattice structure within the perovskite and minimizing the decrease in photoelectric conversion efficiency over time.

[0021] FIG. 1 is a schematic cross-sectional view of a perovskite solar cell according to one embodiment of the present invention.

[0022] FIG. 2 is a graph evaluating the photoelectric conversion efficiency over time of Example 1 and Comparative Example 1 of the present invention.

[0023] FIG. 3 is a graph evaluating the photoelectric conversion efficiency after 2 weeks of Examples 1 to 3 of the present invention.

[0024] Hereinafter, embodiments of the present invention are described in detail so that those skilled in the art can easily implement the invention. The present invention may be embodied in various different forms and is not limited to the embodiments described herein.

[0025]

[0026] The passivation layer of the perovskite solar cell according to the present invention comprises a compound comprising at least one of Al and Si and at least one of N and O, and is implemented to have a density of 1.4 to 2.6 g / cm³.

[0027] The passivation layer of the perovskite solar cell according to the present invention prevents the penetration of moisture, oxygen, etc., thereby ensuring the stability of the device, preventing changes in the lattice structure within the perovskite, and performs the function of exhibiting the effect of minimizing the decrease in photoelectric conversion efficiency over time.

[0028] The above passivation layer comprises a compound containing at least one of Al and Si and at least one of N and O as described above, and preferably AlO x , SiN x and SiO x Including one or more of these can prevent the penetration of moisture, oxygen, etc., thereby ensuring the stability of the device, which can prevent changes in the lattice structure within the perovskite and minimize the decrease in photoelectric conversion efficiency over time, which may be more advantageous in terms of exhibiting an effect.

[0029] In addition, the above passivation layer may have a density of 1.4 to 2.6 g / cm³ as described above, preferably 1.5 to 2.5 g / cm³, and more preferably 2 to 2.2 g / cm³. If the density of the passivation layer is less than 1.4 g / cm³, the initial photoelectric conversion efficiency may be reduced or the decrease in photoelectric conversion efficiency over time may not be minimized, and if the density of the passivation layer exceeds 2.6 g / cm³, pinholes or cracks may occur in the passivation layer.

[0030] In addition, the passivation layer may have a refractive index of 1.65 or higher, and preferably 1.7 or higher, which can prevent voids (empty forms within the unit lattice of the fabric) or pinholes and prevent the penetration of moisture, oxygen, etc., thereby ensuring the stability of the device, which can prevent changes in the lattice structure within the perovskite and minimize the decrease in photoelectric conversion efficiency over time, which may be more advantageous in terms of exhibiting an effect.

[0031] At this time, more preferably, the passivation layer is AlO x In the case including, the passivation layer can be implemented with a refractive index of 1.65 or higher, preferably 1.7 or higher, and the passivation layer is SiN x and SiO x In cases where one or more of the above are included, the passivation layer can be implemented with a refractive index of 1.65 or higher, preferably 1.7 or higher, and more preferably 1.9 or higher. Since the refractive index range according to the material included in the passivation layer is satisfied, it is possible to prevent pores (empty shapes within the original unit lattice) or pinholes and prevent the penetration of moisture, oxygen, etc., thereby ensuring the stability of the device. This can be more advantageous in terms of preventing changes in the lattice structure within the perovskite and minimizing the decrease in photoelectric conversion efficiency over time.

[0032]

[0033] In addition, as illustrated in FIG. 1, the present invention provides a perovskite solar cell (100) comprising a first electrode (10), a hole transport layer (HTL) (20) disposed on the first electrode (10), a photoactive layer (30) disposed on the hole transport layer (20) and having perovskite, an electron transport layer (ETL) (40) disposed on the photoactive layer (30), a second electrode (50) disposed on the electron transport layer (40), and the aforementioned passivation layer (60) disposed on the second electrode (50).

[0034] First, the first electrode (10) may be coated on a predetermined substrate with a material comprising one or more selected from a conductive metal, an alloy of a conductive metal, a metal oxide, and a conductive polymer.

[0035] The above substrate may be a general substrate used in the industry, and for example, a transparent plastic substrate, glass substrate, quartz substrate, silicon substrate, etc., made of materials such as polyethylene terephthalate, polyethylene naphthalate, polyethersulfone, aromatic polyester, or polyimide may be used.

[0036] In addition, the above material may include one or more selected from conductive metals, alloys of conductive metals, metal oxides, and conductive polymers as described above, and preferably may include ITO (Indium Tin Oxide), FTO (Fluorine-doped Tin Oxide), ATO (Sb2O3-doped Tin Oxide), GTO (Gallium-doped Tin Oxide), ZTO (tin-doped zinc oxide), ZTO:Ga (gallium-doped ZTO), IGZO (Indium-gallium zinc oxide), IZO (Indium-doped zinc oxide) and / or AZO (Aluminum-doped zinc oxide), etc.

[0037]

[0038] In addition, the hole transport layer (HTL) (20) and the electron transport layer (ETL) (40) may each independently include inorganic and / or organic transport materials.

[0039] The above-mentioned inorganic delivery material may include one or more selected from nickel oxide (NiOx), CuSCN, CuCrO2, and CuI.

[0040] The above organic carriers are carbazole derivatives, polyarylalkane derivatives, phenylenediamine derivatives, arylamine derivatives, amino-substituted chalcone derivatives, styrylanthracene derivatives, fluorene derivatives, hydrazone derivatives, stilbene derivatives, silazane derivatives, aromatic tertiary amine compounds, styrylamine compounds, aromatic dimethylidine compounds, porphyrin compounds, phthalocyanine compounds, polythiophene derivatives, polypyrrole derivatives, polyparaphenylenevinylene derivatives, pentacene, coumarin 6 (3-(2-benzothiazolyl)-7-(diethylamino)coumarin), ZnPC (zinc phthalocyanine), CuPC (copper phthalocyanine), TiOPC (titanium oxide phthalocyanine), Spiro-MeOTAD(2,2',7,7'-tetrakis(N,Np-dimethoxyphenylamino)-9,9'-spirobifluorene), F16CuPC(copper(II) 1,2,3,4,8,9,10,11,15,16,17,18,22,23,24,25-hexadecafluoro-29H,31H-phthalocyanine), SubPc (boron subphthalocyanine chloride) and N3(cis-di(thiocyanato)-bis(2,2'-bipyridyl-4,4'-dicarboxylic acid)-ruthenium(II), P3HT(poly[3-hexylthiophene]), MDMO-PPV(poly[2-methoxy-5-(3',7'-dimethyloctyloxyl)]-1,4-phenylene vinylene), MEH-PPV(poly[2-methoxy-5-(2''-ethylhexyloxy)-p-phenylene vinylene]), P3OT(poly(3-octyl thiophene)), POT(poly(octyl thiophene)), P3DT(poly(3-decyl thiophene)),P3DDT(poly(3-dodecyl thiophene), PPV(poly(p-phenylene vinylene)), TFB(poly(9,9'-dioctylfluorene-co-N-(4-butylphenyl)diphenyl amine), 폴리아닐린(Polyaniline), Spiro-MeOTAD([2,22′,7,77′-tetrkis (N,N-di-pmethoxyphenyl amine)-9,9,9′-spirobi fluorine]), CuSCN, CuI, PCPDTBT(Poly[2,1,3-benzothiadiazole-4,7-diyl[4,4-bis(2-ethylhexyl-4H-cyclopenta [2,1-b:3,4-b']dithiophene-2,6-diyl]], Si-PCPDTBT(poly[(4,4′-bis(2-ethylhexyl)dithieno[3,2-b:2′,3′-d]silole)-2,6-diyl-alt-(2,1,3-benzothiadiazole)-4,7-diyl]), PBDTTPD(poly((4,8-diethylhexyloxyl), PFDTBT(poly[2,7-(9-(2-ethylhexyl)-9-hexyl-fluorene)-alt-5,5-(4', 7, -di-2-thienyl-2',1', 3'-benzothiadiazole)]), PFO-DBT(poly[2,7-.9,9-(dioctyl-fluorene)-alt-5,5-(4',7'-di-2-.thienyl-2', 1', 3'-benzothiadiazole)]), PSiFDTBT(poly[(2,7-dioctylsilafluorene)-2,7-diyl-alt-(4,7-bis(2-thienyl)-2,1,3-benzothiadiazole)-5,5′-diyl]), PCDTBT(Poly [[9-(1-octylnonyl)-9H-carbazole-2,7-diyl] -2,5-thiophenediyl-2,1,3-benzothiadiazole-4,7-diyl-2,5-thiophenediyl]), PFB(poly(9,9′-dioctylfluorene-co-bis(N,N′-(4,butylphenyl))bis(N,N′-phenyl-1,4-phenylene)diamine), F8BT(poly(9,9′-dioctylfluorene-cobenzothiadiazole), PEDOT (poly(3,4-ethylenedioxythiophene)), PEDOT:PSS It may include poly(3,4-ethylenedioxythiophene) poly(styrenesulfonate), PTAA (poly(triarylamine)), 2-PACz, Me-2PACz, 4-PACz, MeO-4PACz, Me-4PACz and / or MeO-2PACz.

[0041] In addition, methods for forming each of the hole transport layer (20) and the electron transport layer (40) may include coating methods and vacuum deposition methods, and coating methods may include gravure coating, bar coating, printing, spraying, spin coating, dip coating, and die coating.

[0042]

[0043] In addition, the light absorption layer (30) may include a perovskite material, and preferably may include a perovskite material represented by the following chemical formula 1.

[0044] [Chemical Formula 1]

[0045] CMX3

[0046] In Formula 1, C is a monovalent cation and may include an amine, ammonium, a Group 1 metal, a Group 2 metal, and / or other cation or cation-like compound, preferably formamidinium (FA), methylammonium (MA), FAMA, CsFAMA, or N(R)4 +(Here, R may be the same or different group, and R is a straight-chain alkyl group having 1 to 5 carbon atoms, a branched-chain alkyl group having 3 to 5 carbon atoms, a phenyl group, an alkylphenyl group, an alkoxyphenyl group, or an alkyl halide).

[0047] In addition, M of Chemical Formula 1 is a divalent cation and may include one or two types selected from Fe, Co, Ni, Cu, Sn, Pb, Bi, Ge, Ti, Eu, and Zr.

[0048] In addition, X of Formula 1 is a monovalent anion and may include one or more halide elements selected from F, Cl, Br, and I and / or a Group 16 anion, and in a preferred example, X is I x Br 3-x (0≤x≤3) can be

[0049] And, as a preferred embodiment of the above Chemical Formula 1, FAPbI x Br 3-x (0≤x≤3), MAPbI x Br 3-x (0≤x≤3), CsMAFAPbI x Br 3-x (0≤x≤3), CH3NH3PbX3(X=Cl, Br, I, BrI2, or Br2I), CH3NH3SnX3(X=Cl, Br or I), CH(=NH)NH3PbX3(X=Cl, Br, I, BrI2, or Br2I), CH(=NH)NH3SnX3(X=Cl, Br or I), etc.

[0050] In addition, in the solar cell of the present invention, the light absorption layer may be a single layer composed of the same perovskite material, or a multilayer structure in which multiple layers composed of different perovskite materials are stacked, and may include a different type of perovskite material having a pillar shape such as a column shape, plate shape, needle shape, wire shape, or rod shape within the light absorption layer composed of one type of perovskite material.

[0051]

[0052] In addition, the second electrode (50) can be formed by coating or depositing one or more materials selected from Pt, Au, Ni, Cu, Ag, In, Ru, Pd, Rh, Ir, Os, C and conductive polymers.

[0053]

[0054] In addition, the description of the passivation layer (60) is omitted as it is identical to the description of the passivation layer of the perovskite solar cell described above.

[0055]

[0056] Meanwhile, a perovskite solar cell (100) according to one embodiment of the present invention may further include a recombination layer (70) between the first electrode (10) and the hole transport layer (20), and may further include an anti-reflection layer (AR layer) (not shown) between the electron transport layer (40) and the passivation layer (60).

[0057] As the above recombination layer (70) and anti-reflection layer (not shown) may be identical to known recombination layers and anti-reflection layers, they are not specifically described in the present invention.

[0058]

[0059] And, the above perovskite solar cell has a water vapor transmission rate (WVTR) of 0.8 × 10⁻⁶ -3 ~ 1.2×10 -2 g / m 2 It can be day, and preferably the moisture permeability is 10 -3 ~ 10 -2 g / m 2 It can be day. The moisture permeability of the above perovskite solar cell is 0.8×10 -3 g / m 2 If it is less than one day, pinholes or cracks may occur in the passivation layer, and the moisture permeability is 1.2 × 10⁻⁶ -2g / m 2 If the period exceeds one day, the initial photoelectric conversion efficiency may decrease, or it may not be possible to minimize the decrease in photoelectric conversion efficiency over time.

[0060]

[0061] Meanwhile, according to one embodiment of the present invention, the passivation layer described above can be applied to a heterojunction (tandem) perovskite solar cell, and for example, the heterojunction perovskite solar cell may be a solar cell comprising a structure in which a first electrode, a first photoactive layer, a hole transport layer (HTL), a second photoactive layer, an electron transporting layer (ETL), and a second electrode are stacked in sequence.

[0062] The first light-absorbing layer may be a silicon solar cell or a light-absorbing layer comprising the previously described perovskite material.

[0063] The present invention will be explained in more detail below through examples, but the following examples are not intended to limit the scope of the invention and should be interpreted as being for the purpose of aiding understanding of the invention.

[0064] [Example]

[0065] <Example 1: Preparation of Perovskite Solar Cell>

[0066] A glass substrate (thickness 1.1 mm) coated with indium tin oxide (ITO) to a thickness of about 110 nm was cleaned sequentially with acetone and isopropyl alcohol (IPA) using an ultrasonic cleaner for 1 hour each to prepare the first electrode.

[0067] Next, ITO was formed to a thickness of 50 nm as a recombination layer on the first electrode using a Sputter device.

[0068] Next, a hole transport layer (NiO₂) with a thickness of 20 nm is deposited on the recombination layer by a sputtering deposition method.x ) was formed. Next, a photoactive layer solution formed by dissolving dimethylformamide (DMF) : NMP (N-Methyl-2-Pyrrolidone) in a weight ratio of 9:1 was formed on top of the hole transport layer via spin coating, and by heat treatment at 100°C for 20 minutes, a photoactive layer (CsMAFAPbI) having a NiOx hole transport layer and a 500 nm thick perovskite crystal structure was formed. x Br 3-x , 0≤x≤3) was formed (at this time, the formation of the hole transport layer and the photoactive layer was performed in a yellow room to block short-wavelength light under conditions of 20% Rh relative humidity and 21℃ temperature).

[0069] Next, a first electron transport layer (a carbonfullerene compound and a halogenated inorganic compound) with a thickness of 20 nm was formed on the photoactive layer through an evaporator deposition method.

[0070] Next, a second electron transport layer (SnOx) with a thickness of 10 nm was formed on the first electron transport layer using an atomic deposition method.

[0071] Next, a 100 nm thick electrode was deposited on the second electrode using an evaporator method. Subsequently, a perovskite solar cell was fabricated by forming a passivation layer (AlOx) with a density of 2.0 g / cm³ to a thickness of 10 nm using an atomic deposition method, with a process temperature of 95°C and a source input amount of 10 sccm. At this time, the refractive index of the passivation layer was 1.7.

[0072]

[0073] <Example 2>

[0074] A perovskite solar cell was manufactured in the same manner as in Example 1 above, but by depositing AlOx with a thickness of 10 nm using an atomic deposition method at a process temperature of 90°C, thereby changing the density of the passivation layer to 1.78 g / cm³ (the refractive index of the passivation layer is 1.68).

[0075]

[0076] <Example 3>

[0077] A perovskite solar cell was manufactured in the same manner as in Example 1 above, but by depositing AlOx to a thickness of 10 nm using an atomic deposition method at a process temperature of 110°C, thereby changing the density of the passivation layer to 1.9 g / cm³ (refractive index of the passivation layer is 1.68).

[0078]

[0079] <Example 4>

[0080] A perovskite solar cell was manufactured in the same manner as in Example 1 above, but by depositing AlOx with a thickness of 10 nm using an atomic deposition method at a process temperature of 130°C, thereby changing the density of the passivation layer to 2.2 g / cm³ (the refractive index of the passivation layer is 1.69).

[0081]

[0082] <Example 5>

[0083] A perovskite solar cell was manufactured in the same manner as in Example 1 above, but with a Source amount of 2 sccm added to change the refractive index of the passivation layer to 1.55 (the density of the passivation layer was 1.67 g / cm³).

[0084]

[0085] <Example 6>

[0086] A perovskite solar cell was manufactured by carrying out the same procedure as in Example 1 above, but by depositing SiNx to a thickness of 10 nm at a process temperature of 130°C using an atomic deposition method to form a passivation layer with a density of 2.0 g / cm³ (the refractive index of the passivation layer is 1.53).

[0087]

[0088] <Comparative Example 1>

[0089] A perovskite solar cell was manufactured in the same manner as in Example 1 above, but without forming a passivation layer.

[0090]

[0091] <Comparative Example 2>

[0092] A perovskite solar cell was manufactured in the same manner as in Example 1 above, but by using an atomic deposition method to deposit AlOx with a thickness of 10 nm at a process temperature of 50°C, thereby changing the density of the passivation layer to 1.3 g / cm³ (the refractive index of the passivation layer is 1.21).

[0093]

[0094] <Comparative Example 3>

[0095] A perovskite solar cell was fabricated in the same manner as in Example 1 above, but with the density of the passivation layer changed to 2.7 g / cm³ by depositing AlOx with a thickness of 10 nm using an atomic deposition method with a Source input amount of 15 sccm / Reactant Source 5 sccm (refractive index of the passivation layer is 1.57).

[0096]

[0097] <Experimental Example: Measurement of Water Transmittance and Performance of Perovskite Solar Cells>

[0098] For the perovskite solar cells prepared according to the above examples and comparative examples, calcium was deposited on the upper surface of a glass substrate inside a glove box, and a passivation layer was deposited over the entire calcium using an atomic deposition method. Then, the water vapor transmission rate according to the degree of calcium oxidation was evaluated using a calcium test method. The calcium-deposited substrate was connected to an electrical characteristic wire, and the calcium oxidation occurred according to the amount of water vapor transmitted, and the resulting rate of change in resistance was measured. Based on this, the cells were stored in an environment chamber at a temperature of 60°C and a relative humidity of 90%. The measurement results of the solar cells according to the storage period are shown in Tables 1 and 2 below.

[0099] Specifically, the electrical performance of the initial cell was first evaluated using a solar simulator. Then, the electrical performance of the cell over time was evaluated while stored under the aforementioned temperature and relative humidity conditions.

[0100] At this time, for Example 1 and Comparative Example 1, the initial performance, performance after 1 week, performance after 2 weeks, performance after 3 weeks, and performance after 4 weeks were measured (photoelectric conversion efficiency) respectively and are shown in FIG. 2.

[0101] As shown in FIG. 2, it was confirmed that Example 1, which includes a passivation layer, can minimize the decrease in photoelectric conversion efficiency over time compared to Comparative Example 1, which does not include a passivation layer.

[0102] In addition, for Example 2 (passivation layer density 1.7 g / cm³), Example 3 (passivation layer density 1.9 g / cm³), and Example 4 (passivation layer density 2.2 g / cm³), the performance (photoelectric conversion efficiency) after 2 weeks was measured and is shown in Fig. 3.

[0103] As shown in Fig. 3, Example 4, which includes a high-density passivation layer, was found to have excellent photoelectric conversion efficiency even after 2 weeks.

[0104] In addition, moisture permeability, initial performance, and performance after 4 weeks are shown in Tables 1 and 2 below.

[0105] Classification Example 1 Example 2 Example 3 Example 4 Example 5 Initial Performance Open Voltage (V oc , V)1.138 1.112 1.138 1.16 1.130 Short-circuit current density (J sc , mA / cm 2 )19.90 19.7 219.90 20.4 119.41 Fill Factor (FF) 80.3 77 9.6 680.3 77 5.6 27 6.24 Photovoltaic Conversion Efficiency (PCE, %) 18.2 117.9 818.2 117.9 216.7 24 Performance after weeks Open-circuit Voltage (V oc, V)1.143 1.075 1.143 1.130 1.098 Short-circuit current density (J sc , mA / cm 2 )19.85 18.00 19.85 19.41 19.02 Fill Factor (FF) 79.28 79.62 79.28 76.24 74.18 Photovoltaic Conversion Efficiency (PCE, %) 17.99 17.30 17.98 17.77 15.50 Moisture Permeability (g / m² 2 day)5.3×10 -4 6.3×10 -3 5.3×10 -4 4.3×10 -4 2.1×10 -3

[0106] Classification Example 6 Comparative Example 1 Comparative Example 2 Comparative Example 3 Initial Performance Open Voltage (V oc , V)1.147 1.122 1.138 1.129 Short-circuit current density (J sc , mA / cm 2 )19.87 19.96 19.30 19.49 Fill Factor (FF) 80.31 80.83 79.75 79.73 Photovoltaic Conversion Efficiency (PCE, %) 18.30 18.10 17.05 17.704 Performance after weeks Open-circuit Voltage (V oc , V)1.135 1.012 1.075 1.098 Short-circuit current density (J sc , mA / cm 2 )19.77 18.47 18.92 18.75 Fill Factor (FF) 63.75 69.54 74.75 73.97 Photovoltaic Conversion Efficiency (PCE, %) 13.98 14.75 15.50 15.90 Moisture Permeability (g / m²) 2 day)6.1×10 -2 7.1×10 -1 3.5×10 -2 4.9×10 -2

[0107] As can be seen from Tables 1 and 2 above, Examples 1 to 4, which satisfy all of the density, refractive index, and inclusion of the passivation layer according to the present invention, have superior initial solar cell performance and solar cell performance after the passage of time, and significantly lower moisture permeability compared to Examples 5 to 6 and Comparative Examples 1 to 3, which do not satisfy at least one of these.

[0108]

[0109] Although an embodiment of the present invention has been described above, the concept of the present invention is not limited to the embodiments presented in this specification. Those skilled in the art who understand the concept of the present invention may easily propose other embodiments within the scope of the same concept by adding, changing, deleting, or adding components, and such embodiments shall also be considered to fall within the scope of the concept of the present invention.

[0110]

[0111] [Explanation of the symbol]

[0112] 10: First electrode

[0113] 20: Precision Transport Layer

[0114] 30: Photoactive layer

[0115] 40: Electron transport layer

[0116] 50: Second electrode

[0117] 60: Passivation layer

[0118] 70: Recombination layer

Claims

1. A passivation layer of a perovskite solar cell comprising a compound containing at least one of Al and Si and at least one of N and O, having a density of 1.4 to 2.6 g / cm³.

2. In Paragraph 1, The above passivation layer is a passivation layer of a perovskite solar cell having a density of 1.5 to 2.5 g / cm³.

3. In Paragraph 1, The above passivation layer is AlO x , SiN x and SiO x A passivation layer of a perovskite solar cell comprising one or more of the following.

4. In Paragraph 1, The above passivation layer is a passivation layer of a perovskite solar cell having a refractive index of 1.65 or higher.

5. In Paragraph 1, The above passivation layer is SiN x and SiO x A passivation layer of a perovskite solar cell comprising one or more of the following, with a refractive index of 1.85 or higher.

6. First electrode; A hole transport layer (HTL) disposed on the first electrode; A photoactive layer disposed on the above-mentioned hole transport layer and having a perovskite; An electron transport layer (ETL) disposed on the above photoactive layer; A second electrode disposed on the electron transport layer above; and A perovskite solar cell comprising a passivation layer according to any one of claims 1 to 5 disposed on the second electrode.

7. In Paragraph 6, A perovskite solar cell further comprising a recombination layer between the first electrode and the hole transport layer.

8. In Paragraph 6, A perovskite solar cell further comprising an anti-reflection layer (AR layer) between the electron transport layer and the passivation layer.

9. In Paragraph 6, The above perovskite solar cell has a water vapor transmission rate (WVTR) of 0.8 × 10⁻⁶ -3 ~ 1.2×10 -2 g / m 2 Passivation layer of a day perovskite solar cell.

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