Perovskite photodetectors with improved performance and durability and fabrication method thereof

Abstract

The present invention relates to a perovskite photodetector with improved performance and durability and a method for manufacturing the same.

Description

Technology Field

[0001] The present invention relates to a perovskite photodetector with improved performance and durability and a method for manufacturing the same. Background Technology

[0003] A perovskite photodetector refers to a device capable of converting incident light into an electrical signal based on a photosensitive layer with a perovskite (ABX3) structure. Perovskite materials feature an adjustable bandgap (1.5–2.5 eV), low exciton binding energy (~10 meV), and high charge mobility (800 cm⁻¹). 2 It has the advantage of having / Vs) and a long charge diffusion distance (1 μm).

[0005] In conventional optoelectronic devices, perovskite photosensitive layers are coated by dissolving perovskite precursors in a solvent. When using this method, the supersaturated precursors crystallize into perovskite material due to the evaporation of the solvent, forming a solid perovskite thin film. Consequently, numerous defect sites exist on the surface of the perovskite, making it difficult to manufacture high-quality photosensitive layers.

[0007] To control the non-uniform surface of perovskites caused by the rapid reaction and self-assembly properties between perovskite precursors, methods such as using dimethylsulfoxide (DMSO) or utilizing inert gas (N2) instead of ambient air to remove moisture (H2O) have been employed. However, to manufacture perovskite photosensitive layers, it is necessary to lower production costs, increase the uniformity of the photosensitive layer to enhance reproducibility, and secure stable photoelectric conversion efficiency. Accordingly, there is a need for the development of technology capable of more effectively forming high-quality and durable perovskite photosensitive layers.

[0009] Prior art literature

[0010] 1. Prior art patent document KR 10-2023-0106318 The problem to be solved

[0012] The inventors, having made diligent efforts to manufacture a high-quality perovskite photosensitive layer, confirmed that the performance and durability of a perovskite photodetector can be improved by controlling the growth rate of perovskite crystals and passivating defect sites when 1,8-octanedithiol (ODT) is applied as an additive during spin coating of a perovskite precursor solution on a substrate, and subsequently completed the present invention.

[0013] More specifically, the inventors prepared a perovskite photosensitive layer by spin-coating a perovskite precursor solution onto a substrate and applying a mixed antisolvent, in which 1,8-octaneditiol (ODT) is mixed into the antisolvent during spin-coating, onto the substrate. Compared to the case without the addition of 1,8-octaneditiol, the formation and growth rate of the crystalline phase increased (Experimental Example 1), the average particle size (~228.33 nm) and the layer thickness (~252.94 nm) increased (Experimental Example 2), and the hydrophilic surface energy was 62.26 mJ / m². 2 It was confirmed that it can be lowered to (Experimental Example 3). When fabricating a perovskite photodetector including the above MAPbI3 layer, the dark current density under a -0.1 V bias is 2.00 × 10 7 A / cm 2As such, it decreased by more than 20 times compared to the case without 1,8-octaneditiol addition; in the forward bias region, under a 550 nm light source, the open-circuit potential increased by more than 3 times compared to the case without 1,8-octaneditiol addition, and the detection capability increased by more than 4 times compared to the case without 1,8-octaneditiol addition; furthermore, the detection capability was maintained stably compared to the case without 1,8-octaneditiol addition under low light intensity conditions of 1 / 6000 times lower than 1 SUN conditions, and under self-powered conditions, it was improved by ~6.25 times compared to the perovskite photodetector without 1,8-octaneditiol addition, reaching ~2.72 × 10⁻⁶. 13 cmHz 1 / 2 W -1 It was shown (Experimental Example 4), and compared to the perovskite photodetector without 1,8-octanedithil, the rise time of the transient photocurrent of the perovskite photodetector was reduced and the fall time was shortened (Experimental Example 5), and it was confirmed that it could exhibit a detection capability of approximately 90% even after approximately 260 hours (Experimental Example 6). In addition, the detection capability of the perovskite photodetector according to the present invention is approximately 1×10⁻⁶ 13 cmHz 1 / 2 W -1 and EQE max As it was confirmed to be ~86%, it was confirmed that it can exhibit a promising performance level compared to conventional perovskite photodetectors (Experimental Example 7).

[0015] However, the problems that this invention seeks to solve are not limited to those mentioned above, and other unmentioned problems will be clearly understood by those skilled in the art from the description below. means of solving the problem

[0017] The present invention discloses a perovskite photodetector with improved performance and durability and a method for manufacturing the same.

[0019] According to the first embodiment,

[0020] Substrate; and

[0021] It includes a photosensitive layer formed on the above substrate, and

[0022] A perovskite photodetector is disclosed in which the photosensitive layer comprises perovskite and 1,8-octanedthiol (1,8-Octanedithiol, ODT).

[0023] In the present invention, the substrate may be a glass substrate or a flexible polymer film.

[0024] In the present invention, the photodetector further comprises a transparent conductive layer formed between a substrate and a photosensitive layer, and the transparent conductive layer may comprise ITO (Indium Tin Oxide), IZO (Indium Zinc Oxide), ITZO (Indium Tin Zinc Oxide), or a combination thereof.

[0025] In the present invention, the photodetector further comprises a hole transport layer (HTL) formed between the transparent conductive layer and the photosensitive layer, and the hole transport layer may comprise nickel oxide, Spiro-OMeTAD, PTAA, P3HT, PEDOT:PSS, or a combination thereof.

[0026] In the present invention, the photodetector further comprises an electron transport layer (ETL) formed on the photosensitive layer, and the electron transport layer may comprise TiO2, SnO2, ZnO, PCBM, or a combination thereof.

[0027] In the present invention, the photodetector further comprises an electrode layer formed on the electron transport layer, and the electrode may comprise gold (Au), silver (Ag), aluminum (Al), platinum (Pt), nickel (Ni), ITO (Indium Tin Oxide), carbon, EGaIn, or a combination thereof.

[0029] According to the second embodiment,

[0030] A step of spin-coating a perovskite precursor solution onto a substrate;

[0031] A step of applying a mixed antisolvent, in which 1,8-octanedithiol (1,8-Octanedithiol, ODT) is mixed with the antisolvent during the spin coating above, onto a substrate; and

[0032] A step of heat-treating the perovskite layer formed on the substrate.

[0033] A method for manufacturing a perovskite photodetector comprising the above is disclosed. According to the present invention, fast precipitation of perovskite can be induced by applying a mixed antisolvent, in which 1,8-octanedithiol (ODT) is mixed with the antisolvent during spin coating, onto a substrate.

[0034] In the present invention, the perovskite precursor solution may comprise a compound satisfying the following chemical formula 1, a compound satisfying the following chemical formula 2, and a solvent.

[0035] [Chemical Formula 1]

[0036] AX

[0037] [Chemical Formula 2]

[0038] MX2

[0039] (In the above chemical formulas 1 and 2,

[0040] A is Cs + or is an organic cation;

[0041] M is selected from the group consisting of Pb, Cu, Ni, Co, Fe, Mn, Cr, Pd, Cd, Yb, Sn, Ge and combinations thereof;

[0042] X is Br - , Cl - or I - am)

[0043] In the present invention, the solvent may include dimethyl sulfoxide (DMSO), gamma-butyrolactone (γGBL), diethyl sulfoxide, methyl ethyl sulfoxide, pyrrolidone derivatives, amide derivatives, N,N'-dimethylpropyleneurea derivatives, or a combination thereof.

[0044] In the present invention, the perovskite precursor solution and 1,8-octanedithol are in a ratio of 1:1 x 10⁻⁶ -6 Inner 1 : 200x10 -6 It can be added in a molar ratio.

[0045] In the present invention, the antisolvent may include chlorobenzene, chloroform, hexene, cyclohexene, 1,4-dioxane, benzene, toluene, triethylamine, ethylamine, ethylether, ethyl acetate, acetic acid, 1,2-dichlorobenzene, tert-butyl alcohol, 2-butanol, isopropanol, methylethylketone, or a combination thereof.

[0046] In the present invention, the 1,8-octanedithiol may be included in an amount of 0.1 to 5 vol% based on the mixed antisolvent.

[0047] In the present invention, the 1,8-octanedithiol may be included in an amount of 1 to 50 μL based on the mixed antisolvent.

[0048] In the present invention, the heat treatment may be performed at 80-125 ℃ for 3 to 5 minutes.

[0049] In the present invention, the method is:

[0050] Step of forming a transparent conductive layer on a substrate;

[0051] A step of forming a hole transport layer on the transparent conductive layer;

[0052] A step of forming a photosensitive layer on the hole transport layer above;

[0053] A step of forming an electron transport layer on the above photosensitive layer; and

[0054] The method includes the step of forming an electrode on the electron transport layer,

[0055] Here, the step of forming the photosensitive layer is:

[0056] A step of spin-coating a perovskite precursor solution onto a substrate;

[0057] A step of applying a mixed antisolvent, in which 1,8-octanedithiol (1,8-Octanedithiol, ODT) is mixed with the antisolvent during the spin coating above, onto a substrate; and

[0058] It may include a step of heat-treating the perovskite layer formed on the substrate.

[0059] In the present invention, the method is:

[0060] A step of forming a transparent conductive layer of ITO (Indium Tin Oxide) on a glass substrate;

[0061] A step of forming a PEDOT:PSS hole transport layer on the above ITO transparent conductive layer;

[0062] A step of forming a photosensitive layer on the above PEDOT:PSS hole transport layer;

[0063] A step of forming a PCBM electron transport layer on the above photosensitive layer; and

[0064] The method includes the step of forming an AI electrode on the PCBM electron transport layer.

[0065] Here, the step of forming the photosensitive layer is:

[0066] A step of spin-coating a perovskite precursor solution comprising methylammonium ioid (CH3NH3I), lead(II) oxide (PbI2), dimethyl sulfoxide (DMSO), and γ-butyrolactone (GBL) onto a substrate;

[0067] A step of applying a mixed antisolvent, comprising chlorobenzene (CB) mixed with 1,8-octanedithiol (ODT), onto a substrate during the spin coating; and

[0068] The method may include a step of heat-treating the perovskite layer formed on the substrate at 80-125°C for 3 to 5 minutes. Effects of the invention

[0070] According to the present invention, when a perovskite photosensitive layer is prepared by applying an antisolvent containing 1,8-octanedithiol (ODT) onto a substrate during spin coating of a perovskite precursor solution onto a substrate, the generation and growth rate of the crystalline phase can be increased, and the hydrophilic surface energy is 62.26 mJ / m² 2 It can be lowered to. In addition, the photodetector including the perovskite photosensitive layer according to the present invention can not only improve dark current density, responsiveness, and detection capability, but also significantly improve durability.

[0072] Meanwhile, the scope of the present invention is not limited by the effects described above. Brief explanation of the drawing

[0074] FIG. 1 shows a cross-sectional view of a perovskite photodetector according to one embodiment of the present invention. Figure 2 shows the FT-IR (Fourier transform infrared) analysis results of perovskite thin films with or without ODT addition, showing (a) adduct phase MAPbI3, (b) crystalline phase MAPbI3, (c) S=O peak intensity, (d) NH / S=O ratio, and (e) NH / CN ratio. Figure 3 shows the results of the morphology and crystallinity analysis of MAPbI3 thin films according to ODT concentration, including the surface morphology of field emission scanning electron microscope (FE-SEM) images of MAPbI3 thin films treated with molar ODT concentrations of (a) 0 μmol, (b) 27.2 μmol, (c) 54.4 μmol, (d) 108.8 μmol, and (e) 163.2 μmol, (f) the average particle size of MAPbI3 thin films treated with molar ODT concentrations (0 μmol, 27.2 μmol, 54.4 μmol, 108.8 μmol, 163.2 μmol), and (g) X-ray diffraction (XRD) patterns. Figure 4 shows field emission scanning electron microscope (FE-SEM)-based cross-sectional images of a perovskite layer with or without ODT addition. Figure 5 shows the contact angle and surface energy analysis results of MAPbI3 thin films according to ODT concentration, and represents the contact angle and surface energy of samples having a glass / PEDOT:PSS / MAPbI3 structure treated with ODT molar concentrations (0 μmol, 27.7 μmol, 54.4 μmol, 108.8 μmol, 163.2 μmol). Figure 6 shows the results of analyzing parameters measured under bias conditions of a perovskite photodetector with or without ODT addition, including (a) current density-voltage (JV) curve under dark conditions, (b) current density-voltage (JV) curve under 550 nm conditions, (c) responsiveness (-0.1 V applied bias), (d) detection capability (0.1 V applied bias), (e) linear dynamic range by light intensity, and (f) open circuit voltage (depending on light intensity). Fig. 7 shows 1 SUN (AM 1.5G, 100 mW / cm²) 2 This shows the operating characteristics of a perovskite photodetector with ODT added compared to a perovskite photodetector without ODT added under conditions of 1 / 6000 times lower light intensity than the condition. Figure 8 shows the results of the analysis of the photoresponse characteristics of a perovskite photodetector with or without the addition of ODT, including (a) normalized current density-time response on test, (b) normalized current density-time response off test, (c) steady-state photoluminescence (PL) spectrum (PL mapping 2.5 μm x 2.5 μm), (d) time-resolved photoluminescence spectrum, (e) electrochemical impedance spectroscopy (EIS) under light conditions, and electrochemical impedance spectroscopy results under dark conditions. Figure 9 shows the results of the analysis of the detection capability of a perovskite photodetector with or without the addition of ODT, showing the detection capability (0.1 V applied bias) for ~260 hours. Figure 10 shows a graph comparing the detection capability and EQEmax parameters of an ODT-added perovskite photodetector according to the present invention and a conventional perovskite photodetector. Specific details for implementing the invention

[0075] Hereinafter, a perovskite photodetector with improved performance and durability and a method for manufacturing the same, according to a specific embodiment of the invention, will be described in detail. However, this is presented as one example of the invention and does not limit the scope of the invention, and it is obvious to those skilled in the art that various modifications to the embodiment are possible within the scope of the invention. Throughout this specification, unless otherwise specifically stated, "includes" or "contains" refers to the inclusion of any component (or constituent) without any particular limitation and should not be interpreted as excluding the addition of other components (or constituents).

[0076] Expressions such as "comprising" as used in this specification should be understood as open-ended terms implying the possibility of including other embodiments, unless specifically otherwise stated in the phrase or sentence containing such expression.

[0077] As used herein, "preferred" and "preferably" refer to embodiments of the invention that may provide certain advantages under certain conditions. However, other embodiments may also be preferred under the same or different conditions. Additionally, the mention of one or more preferred embodiments does not imply that other embodiments are not useful, nor is it intended to exclude other embodiments from the scope of the invention.

[0078] Unless a specific order is clearly indicated in the context, each step may occur differently from the specified order. That is, each step may occur in the same order as specified, may be performed substantially simultaneously, or may be performed in the reverse order.

[0079] In this specification, when it is stated that a component is located 'on' another component, this includes not only cases where a component is in contact with another component, but also cases where another component exists between the two components.

[0081] 1. Perovskite photodetector

[0082] The present invention

[0083] Substrate; and

[0084] It includes a photosensitive layer formed on the above substrate, and

[0085] The present invention aims to provide a perovskite photodetector in which the photosensitive layer comprises perovskite and 1,8-octanedithil (1,8-Octanedithiol, ODT).

[0086] In the perovskite photodetector according to the present invention, the substrate may be a glass substrate or a flexible polymer film. The polymer film may include PEN (Polyethylene naphthalate), PET (Polyethylene terephthalate), PEI (Polyethylenimine), or a combination thereof, but is not limited thereto.

[0087] In the perovskite photodetector according to the present invention, the 1,8-octanedithiol can be chemically bonded to the cation of the perovskite.

[0088] In the perovskite photodetector according to the present invention, the 1,8-octanedithiol may exist in a coordinate bonded state with the cation of the perovskite.

[0089] In a perovskite photodetector according to the present invention, the photodetector may further include a transparent conductive layer formed between a substrate and a photosensitive layer. The transparent conductive layer may include ITO (Indium Tin Oxide), IZO (Indium Zinc Oxide), ITZO (Indium Tin Zinc Oxide), or a combination thereof, but is not limited thereto.

[0090] In the perovskite photodetector according to the present invention, the photodetector may further include a hole transport layer (HTL) formed between the transparent conductive layer and the photosensitive layer. For example, the hole transport layer may include nickel oxide, Spiro-OMeTAD, PTAA, P3HT, PEDOT:PSS, or a combination thereof, but is not limited thereto.

[0091] In the perovskite photodetector according to the present invention, the photodetector may further include an electron transport layer (ETL) formed on the photosensitive layer. For example, the electron transport layer may include TiO2, SnO2, ZnO, PCBM, or a combination thereof, but is not limited thereto.

[0092] In the perovskite photodetector according to the present invention, the photodetector may further include an electrode layer formed on the electron transport layer. For example, the electrode may include gold (Au), silver (Ag), aluminum (Al), platinum (Pt), nickel (Ni), ITO (Indium Tin Oxide), carbon, EGaIn, or a combination thereof, but is not limited thereto.

[0093] According to one embodiment, the perovskite photodetector according to the present invention is:

[0094] Substrate;

[0095] A transparent conductive layer formed on the above substrate;

[0096] A hole transport layer formed on the above transparent conductive layer;

[0097] A photosensitive layer formed on the above-mentioned hole transport layer;

[0098] An electron transport layer formed on the above photosensitive layer; and

[0099] It includes an electrode formed on the electron transport layer above, and

[0100] Here, the photosensitive layer may include perovskite and 1,8-octanedithol (ODT). Referring to FIG. 1, a perovskite photodetector (100) according to the present invention may include a substrate (not shown), a transparent conductive layer (10), a hole transport layer (20), a perovskite photosensitive layer (30) containing 1,8-octanedithol, a sperm transport layer (40), and an electrode.

[0101] As described above, the perovskite photodetector according to the present invention may have a perovskite layer containing 1,8-octanedithil (ODT). The 1,8-octanedithil (ODT) may be positioned within the perovskite layer between or at the boundaries of perovskite grains, thereby surrounding the perovskite or filling the spaces between the perovskites. That is, the 1,8-octanedithil (ODT) is an amine, PbX 3 Region and low-coordinate Pb 2+ By existing in a chemical bonding state to ions, for example, a coordinate bond, the growth rate of perovskite crystals can be controlled and defect sites can be passivated, thereby significantly improving performance such as dark current density, responsiveness, and durability.

[0103] 2. Method for manufacturing a perovskite photodetector

[0104] The present invention

[0105] A step of spin-coating a perovskite precursor solution onto a substrate;

[0106] A step of applying a mixed antisolvent, in which 1,8-octanedithiol (1,8-Octanedithiol, ODT) is mixed with the antisolvent during the spin coating above, onto a substrate; and

[0107] A step of heat-treating the perovskite layer formed on the substrate.

[0108] including,

[0109] The present invention aims to provide a method for manufacturing a perovskite photodetector.

[0110] In a method for manufacturing a perovskite photodetector according to the present invention, the perovskite precursor solution may include a compound satisfying the following chemical formula 1, a compound satisfying the following chemical formula 2, and a solvent.

[0111] [Chemical Formula 1]

[0112] AX

[0113] [Chemical Formula 2]

[0114] MX2

[0115] (In the above chemical formulas 1 and 2,

[0116] A is Cs + or is an organic cation;

[0117] M is selected from the group consisting of Pb, Cu, Ni, Co, Fe, Mn, Cr, Pd, Cd, Yb, Sn, Ge and combinations thereof;

[0118] X is Br - , Cl - or I - am)

[0119] For example, the above chemical formula 1 may be CH3NH3I (methylammonium iodide), CH(NH2)2I (formamidinium iodide) or CsI (cesium iodide).

[0120] For example, the solvent may include, but is not limited to, dimethyl sulfoxide (DMSO), gamma-butyrolactone (γGBL), diethyl sulfoxide, methyl ethyl sulfoxide, pyrrolidone derivatives, amide derivatives, N,N'-dimethylpropyleneurea derivatives, or combinations thereof.

[0121] In a method for manufacturing a perovskite photodetector according to the present invention, the perovskite precursor solution and 1,8-octanedithiol are in a ratio of 1:1 x 10 -6 Inner 1 : 200x10 -6 It can be added in a molar ratio of . Preferably, the perovskite precursor solution and 1,8-octaneditiol are 1:2x10 -6 Inner 1 : 100x10 -6 It can be added in a molar ratio of . More preferably, the perovskite precursor solution and 1,8-octanedithol are 1:4x10 -6Inner 1: 60x10 -6 It can be added in a molar ratio.

[0122] In a method for manufacturing a perovskite photodetector according to the present invention, the antisolvent may include, but is not limited to, chlorobenzene, chloroform, hexene, cyclohexene, 1,4-dioxane, benzene, toluene, triethylamine, ethylamine, ethylether, ethyl acetate, acetic acid, 1,2-dichlorobenzene, tert-butyl alcohol, 2-butanol, isopropanol, methylethylketone, or a combination thereof.

[0123] In the method for manufacturing a perovskite photodetector according to the present invention, the 1,8-octanedithol may be included in an amount of 0.1 to 5 vol% based on the mixed semi-solvent. Preferably, the 1,8-octanedithol may be included in an amount of 0.5 to 3.5 vol% based on the mixed semi-solvent, and most preferably, the 1,8-octanedithol may be included in an amount of 0.5 to 2.0 vol% based on the mixed semi-solvent.

[0124] In the method for manufacturing a perovskite photodetector according to the present invention, the 1,8-octaneditiol may be included in an amount of 1 to 50 μL based on the mixed semi-solvent. Preferably, the 1,8-octaneditiol may be included in an amount of 5 to 30 μL based on the mixed semi-solvent, and most preferably, the 1,8-octaneditiol may be included in an amount of 5 to 20 μL based on the mixed semi-solvent.

[0125] In the method for manufacturing a perovskite photodetector according to the present invention, the heat treatment may be performed at 80-125 ℃ for 3 to 5 minutes.

[0126] According to one embodiment, in a method for manufacturing a perovskite photodetector of the present invention, the method

[0127] Step of forming a transparent conductive layer on a substrate;

[0128] A step of forming a hole transport layer on the transparent conductive layer;

[0129] A step of forming a photosensitive layer on the hole transport layer above;

[0130] A step of forming an electron transport layer on the above photosensitive layer; and

[0131] The method includes the step of forming an electrode on the electron transport layer,

[0132] Here, the step of forming the photosensitive layer is:

[0133] Step of preparing a perovskite precursor solution;

[0134] A step of spin-coating a perovskite precursor solution onto a substrate;

[0135] A step of applying a mixed antisolvent, in which 1,8-octanedithiol (1,8-Octanedithiol, ODT) is mixed with the antisolvent during the spin coating above, onto a substrate; and

[0136] A step of heat-treating the perovskite layer formed on the substrate.

[0137] It may include.

[0138] For example, a method for manufacturing a perovskite photodetector according to the present invention

[0139] A step of forming a transparent conductive layer of ITO (Indium Tin Oxide) on a glass substrate;

[0140] A step of forming a PEDOT:PSS hole transport layer on the above ITO transparent conductive layer;

[0141] A step of forming a photosensitive layer on the above PEDOT:PSS hole transport layer;

[0142] A step of forming a PCBM electron transport layer on the above photosensitive layer; and

[0143] The method includes the step of forming an AI electrode on the PCBM electron transport layer.

[0144] Here, the step of forming the photosensitive layer is:

[0145] A step of spin-coating a perovskite precursor solution comprising methylammonium ioid (CH3NH3I), lead(II) oxide (PbI2), dimethyl sulfoxide (DMSO), and γ-butyrolactone (GBL) onto a substrate;

[0146] A step of applying a mixed antisolvent, comprising chlorobenzene (CB) mixed with 1,8-octanedithiol (ODT), onto a substrate during the spin coating; and

[0147] The method may include a step of heat-treating the perovskite layer formed on the substrate at 80-125°C for 3 to 5 minutes.

[0148] According to one embodiment, in the method for manufacturing a perovskite photodetector of the present invention, the perovskite layer may have a reduced S=O peak according to the Fourier transform infrared (FTIR) spectrum compared to a 1,8-octanedithol-untreated perovskite layer (Experimental Example 1).

[0149] According to one embodiment, in the method for manufacturing a perovskite photodetector of the present invention, the average particle size of the perovskite layer as measured by a field emission scanning electron microscope (FE-SEM) may be 130 to 300 nm. The thickness of the perovskite layer as measured by a field emission scanning electron microscope (FE-SEM) may be 240 to 280 nm (Experimental Example 2).

[0150] According to one embodiment, in a method for manufacturing a perovskite photodetector of the present invention, the contact angle evaluated with DI water on the perovskite layer may be 35 to 50°. The surface energy of the perovskite layer is 60 to 67 mJ / m² 2 It may be (Experimental Example 3).

[0151] According to one embodiment, in the method for manufacturing a perovskite photodetector of the present invention, the dark current density under reverse voltage bias conditions (-0.1 V) of the perovskite photodetector can be reduced by 20 to 25 times compared to a perovskite photodetector without 1,8-octanedithil added. For example, under reverse voltage bias conditions (-0.1 V) of the perovskite photodetector, the dark current density is 2.00 × 10⁻⁶ -7 A / cm 2 It may be (Experimental Example 4).

[0152] According to one embodiment, in the method for manufacturing a perovskite photodetector of the present invention, the open-circuit potential under a 550 nm light source in the forward bias region of the perovskite photodetector can be increased by more than 3 times compared to a perovskite photodetector without 1,8-octanedithil added (Experimental Example 4).

[0153] According to one embodiment, in the method for manufacturing a perovskite photodetector of the present invention, the detection capability of the perovskite photodetector can be increased by more than 4 times compared to a perovskite photodetector without 1,8-octanedithil at 680 nm or 660 nm under reverse voltage bias conditions (-0.1 V) (Experimental Example 4).

[0154] According to one embodiment, in the method for manufacturing a perovskite photodetector of the present invention, the transient photocurrent of the perovskite photodetector can have a reduced rise time and a shortened fall time compared to a perovskite photodetector without 1,8-octanedithil added (Experimental Example 5).

[0155] According to one embodiment, in the method for manufacturing a perovskite photodetector of the present invention, the perovskite photodetector can maintain a performance of 90% or more even after 260 hours (Experimental Example 6).

[0156] According to one embodiment, in the method for manufacturing a perovskite photodetector of the present invention, the perovskite photodetector can maintain a performance of 90% or more even after 260 hours (Experimental Example 6).

[0157] According to one embodiment, in a method for manufacturing a perovskite photodetector of the present invention, the perovskite photodetector has a detection capability of 9.5 × 10⁻⁶ 12 Up to 1×10 13 cmHz 1 / 2 W -1 and EQE max It can be 85 to 90% (Experimental Example 7).

[0159] Various embodiments are presented below to aid in understanding the invention. The following embodiments are provided merely to facilitate a better understanding of the invention and do not limit the scope of protection of the invention to the following embodiments.

[0161] Ingredients

[0162] A MAPbI3 precursor solution was prepared based on a concentration of 1.4 M. Specifically, CH3NH3I (99.99%, Dyesol-Timo Co., Ltd.) and lead(II) oxide (PbI2, 99.99%, TCI Co., Ltd.) as precursors were dissolved in a mixed solvent of dimethyl sulfoxide (DMSO, Junsei Co., Ltd.) and γ-butyrolactone (GBL, Sigma-Aldrich) (DMSO:GBL=3:7), and the mixture was treated with a mixed antisolvent. In this case, the mixed semisolvent used chlorobenzene (CB, Sigma-Aldrich) as the semisolvent and 1,8-octanedithil (ODT, Sigma-Aldrich) at concentrations of 0, 27.7, 54.4, 108.8, and 163.2 μmol as the additive (the volume of ODT corresponded to 0.0.5v%, 1v%, 2v%, and 3v%, respectively, based on 100% of the mixed semisolvent volume). As for the intermediate layer materials, poly(3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS (AI4083), Heraeus Co.) was used as the hole transport material and 6,6-phenyl-C70-methyl butyrate ester (PC 70 BM, Nano-C Inc.) was used. The photosensitive and electron transport materials were stirred in a glove box (Ar atmosphere) for more than 12 hours. All other chemicals were purchased from Sigma-Aldrich and used exactly as received.

[0164] <Example>

[0165] Manufacturing of light-sensing sensors (photodetectors)

[0166] The glass / indium tin oxide (ITO) substrate was cleaned by ultrasonically treating it with deionized water (DI), acetone, and isopropanol (IPA) solvents for 20 minutes, and then dried to remove residual solvents and impurities. To modify the hydrophilic surface, the glass / ITO substrate was treated with UV / O3 for 15 minutes. Next, PEDOT:PSS (AI4083) was spin-coated onto the glass / ITO substrate and annealed on a hot plate (~145°C) for 10 minutes to form a hole transport layer. Then, a mixture of MAPbI3 and 1,8-octaneditiol (0 μmol, 27.7 μmol, 54.4 μmol, 108.8 μmol, and 163.2 μmol) was spin-coated onto the hole transport layer and annealed on a hot plate (~100°C) for 4 minutes to form a photosensitive layer. Next, PC was applied to the photosensitive layer. 70 A BM is spin-coated to form an electron transport layer, and finally, under high vacuum conditions (~1.9 × 10⁻⁶ -6 An AI cathode was formed by thermal deposition in Torr.

[0168] <Experimental Example>

[0169] Experimental Example 1. FT-IR analysis results of perovskite thin films depending on the presence or absence of ODT addition

[0170] Referring to the Fourier Trans Infrared (FTIR) spectrum results of the MAPbI3 thin film with and without ODT addition (Figs. 1a-b), at 4000-500 cm⁻¹ -1 When ODT is added to the spectrum, the main peaks of the perovskite adduct phase and crystalline phase are 3190, 1469, 1403, and 1020 cm⁻¹. -1These were observed and were identified as NH stretching, NH bending, CN, and S=O, respectively (Figs. 2a-b). Furthermore, a comparison of each peak according to phase change revealed that the intensity of the S=O peak decreased as the phase changed from the adduct phase to the crystalline phase. Since a lower decrease in the S=O peak was observed when ODT was added compared to the case without ODT (Fig. 2c), it was confirmed that more DMSO residue could be removed when ODT was added. Therefore, it was found that when ODT was added, the NH / S=O ratio increased and crystallization accelerated as the phase changed to the crystalline phase (Fig. 2d), and the crystal growth rate increased (Fig. 2e).

[0172] Experimental Example 2. MAPbI according to ODT concentration 3 Analysis results of thin film morphology and crystallinity

[0173] Based on the field emission scanning electron microscope (FE-SEM) analysis results of the MAPbI3 thin film according to ODT concentration, it was found that the particle size increased when ODT was added, and in particular, when ODT was added at a concentration of 54.4 μmol, the average particle size of the perovskite increased to approximately 230 nm (Fig. 3a-g). In addition, cross-sectional FE-SEM analysis of the thickness of the MAPbI3 layer showed that the thickness of the layer when ODT was added (54.4 μmol) was approximately 253 nm, which is an increase of about 20 nm compared to the thickness of the layer when ODT was not added (Fig. 4).

[0174] Likewise, in the analysis of the XRD (X-ray diffraction) pattern of the MAPbI3 thin film according to ODT concentration, main peaks corresponding to the perovskite crystal planes (110) and (220) were observed at 13.91° and 28.20° (Fig. 3g).

[0176] Experimental Example 3. MAPbI according to ODT concentration 3 Analysis results of thin film contact angle and surface energy

[0177] Referring to the analysis results of the contact angle and surface energy of MAPbI3 thin films according to ODT concentration, it was found that the contact angle of the MAPbI3 thin film increased and the surface energy decreased upon the addition of ODT; in particular, when ODT was added at a concentration of 54.4 μmol, the surface energy of the perovskite thin film was 62.26 mJ / m². 2 It was confirmed that it decreases to (Fig. 5).

[0179] Experimental Example 4. Analysis results of photoelectronic characteristics of perovskite photodetectors depending on the presence or absence of ODT addition

[0180] Parameters / Condition Jd(A / cm 2 ) R(A / W) D*(Jones) LDR(dB) ODT not added 4.45 × 10 -6 0.379 3.15 × 10 11 110.38 ODT addition 2.00 × 10 -7 0.366 1.45 × 10 12 128.96

[0181] As a result of comparing the current density distribution at each voltage under reverse voltage bias conditions (-0.1 V) of the MAPbI3 photodetector with and without the addition of ODT (54.4 μmol), the dark current density (J d ) is 2.00 × 10 -7 A / cm 2 As such, the dark current density in the case where ODT is not added is 4.45 × 10 -6 A / cm 2 Compared to that, it was found to be suppressed by about 22.25 times (Fig. 6a), and accordingly, it was confirmed that shunt resistance can be significantly improved when ODT is added.

[0182] As a result of comparing the photovoltaic effect under a 550 nm light source in the forward bias region of the MAPbI3 photodetector with and without the addition of ODT (54.4 μmol), when ODT was added, a photovoltage approximately three times higher was generated compared to when ODT was not added, and a stable JV (current density versus voltage) was observed (Fig. 6b).

[0183] Performance parameters of the MAPbI3 photodetector were compared with and without the addition of ODT (54.4 μmol). Specifically, when comparing the responsivity (R) under -0.1 V bias, the responsivity (~350-800 nm) of the two perovskite photodetectors was found to be similar (Fig. 6c), and the detection capability (D*) increased by approximately 4.6 times at 680 nm and 4.96 times at 660 nm when ODT was added under -0.1 V bias compared to when ODT was not added (Fig. 6d), confirming that dark current can be effectively suppressed by the addition of ODT. In addition, when comparing the J and Voc (open circuit voltage) characteristics according to light intensity, it was confirmed that adding ODT allows for a wider range of photo-responsivity, as the linear dynamic range (LDR) increased by approximately 1.17 times from 110.38 dB when ODT was not added to 128.96 dB when ODT was added (Fig. 6e), and it was found that the voltage according to light intensity exhibited a linear proportional characteristic in both cases with and without ODT (Fig. 6f).

[0184] Meanwhile, 1 SUN (AM 1.5G, 100 mW / cm²) 2As a result of comparing the operating characteristics of a perovskite photodetector with ODT added versus a perovskite photodetector without ODT under a light intensity 1 / 6000 times lower than the 1 SUN condition, it was found that the detection capability of the perovskite photodetector with ODT added remained stable compared to the one without ODT, even with bias changes (within the range of -1.0 to 0.2 V) under light intensity 1 / 6000 times lower than the 1 SUN condition. Against this backdrop, an analysis of detection capability revealed that under self-powered conditions, the perovskite photodetector with ODT added achieved ~2.72 × 10⁻⁶, an improvement of ~6.25 times compared to the perovskite photodetector without ODT. 13 cmHz 1 / 2 W -1 It was confirmed to represent (Fig. 7).

[0186] Experimental Example 5. Results of analysis of photoresponse characteristics of perovskite photodetectors depending on the addition of ODT

[0187] As a result of comparing the transient photocurrent of the MAPbI3 photodetector with and without the addition of ODT (54.4 μmol), the rise time of the photodetector with ODT added was reduced by 1.92 μs compared to the rise time of 15.36 μs of the photodetector without ODT added (Fig. 8a), and the fall time of the photodetector with ODT added was shortened by 0.67 μs compared to the rise time of 21.78 μs of the photodetector without ODT added (Fig. 8b), indicating that the photoresponse occurs faster when ODT is added.

[0188] For a more accurate analysis, steady-state PL and PL mapping were analyzed in glass / MAPbI3 with and without the addition of ODT (54.4 μmol). The results showed that when ODT was added, the PL intensity increased by approximately 1.88 times compared to the case without ODT. Similarly, in the PL mapping distribution, a high-intensity orange region was predominantly observed when ODT was added, whereas a low-intensity blue distribution was predominantly observed when ODT was not added, confirming that the charge generation tendency in the photosensitive layer was enhanced upon the addition of ODT (Fig. 8c). Based on this, time-resolved photoluminescence (TRPL) characteristics were analyzed to compare charge flow trends. The results showed that when ODT was added, τ avg It was found to be 10.47 ns, which is a significant improvement compared to 5.61 ns when ODT is not added (Fig. 8d).

[0189] In addition, impedance spectroscopy analysis was performed with and without the addition of ODT (54.4 μmol) to compare charge transfer and recombination trends. As a result, when ODT was added, the series resistance (R) under light conditions s ) and R CT As the values ​​were 17.46 Ω and 28.29 Ω, respectively, which are lower compared to 25.91 Ω and 47.36 Ω without ODT addition, it was confirmed that charge transfer was improved when ODT was added (Fig. 8e). In addition, when ODT was added under dark conditions, the recombination resistance (R sh It was confirmed that the ohmic shunt through the perovskite crystal boundary can be reduced when ODT is added, as the value increased by approximately 4.62 times compared to the case without ODT (Fig. 8f).

[0191] Experimental Example 6. Results of durability analysis of perovskite photodetectors depending on the addition of ODT

[0192] The durability of the MAPbI3 photodetector with and without the addition of ODT (54.4 μmol) was compared by integrating the output for each wavelength value in the photosensitive region of 300-900 nm under -0.1 V. As a result, it was confirmed that the durability of the MAPbI3 photodetector can be significantly improved by the addition of ODT, as the performance was maintained at approximately 90% even after about 260 h when ODT was added (Fig. 9).

[0194] Experimental Example 7. Comparison of the detection capability of the perovskite photodetector according to the present invention and the detection capability of a conventionally known photodetector

[0195] When comparing the performance (maximum EQE (%) and D*) of a perovskite photodetector with ODT (54.4 μmol) added according to the present invention with the performance of a conventionally known photodetector, the photodetector according to the present invention has a D of 9.9×10 12 cmHz 1 / 2 W 1 and EQE max It was confirmed to show ~86%, indicating a promising level compared to previous studies (Fig. 10).

[0197] Specific parts of the present invention have been described in detail above. It is evident to those skilled in the art that such specific descriptions are merely preferred embodiments and do not limit the scope of the invention. Accordingly, the actual scope of the invention is defined by the appended claims and their equivalents.

Claims

Claim 1 The method comprises the steps of: spin-coating a perovskite precursor solution onto a substrate; applying a mixed half-solvent onto the substrate during spin-coating, wherein 1,8-octanedithol (ODT) is mixed into the half-solvent; and heat-treating a perovskite photosensitive layer formed on the substrate; wherein the perovskite precursor solution and 1,8-octanedithol are in a ratio of 1:4 x 10⁻⁶ -6 Inner 1: 60x10 -6 A method for manufacturing a perovskite photodetector in which the components are added in a molar ratio. Claim 2 A method for manufacturing a perovskite photodetector according to claim 1, wherein the substrate is a glass substrate or a flexible polymer film. Claim 3 A method for manufacturing a perovskite photodetector according to claim 1, wherein the photodetector further comprises a transparent conductive layer formed between a substrate and a photosensitive layer, and the transparent conductive layer comprises ITO (Indium Tin Oxide), IZO (Indium Zinc Oxide), ITZO (Indium Tin Zinc Oxide), or a combination thereof. Claim 4 A method for manufacturing a perovskite photodetector according to claim 3, wherein the photodetector further comprises a hole transport layer (HTL) formed between the transparent conductive layer and the photosensitive layer, and the hole transport layer comprises nickel oxide, Spiro-OMeTAD, PTAA, P3HT, PEDOT:PSS, or a combination thereof. Claim 5 A method for manufacturing a perovskite photodetector according to claim 1, wherein the photodetector further comprises an electron transport layer (ETL) formed on a photosensitive layer, and the electron transport layer comprises TiO2, SnO2, ZnO, PCBM, or a combination thereof. Claim 6 A method for manufacturing a perovskite photodetector according to claim 5, wherein the photodetector further comprises an electrode layer formed on the electron transport layer, and the electrode comprises gold (Au), silver (Ag), aluminum (Al), platinum (Pt), nickel (Ni), ITO (Indium Tin Oxide), carbon, EGaIn, or a combination thereof. Claim 7 delete Claim 8 A method for manufacturing a perovskite photodetector according to claim 1, wherein the perovskite precursor solution comprises a compound satisfying the following chemical formula 1, a compound satisfying the following chemical formula 2, and a solvent. [Chemical Formula 1]AX[Chemical Formula 2]MX2(in the above chemical formulas 1 and 2, A is Cs + or is an organic cation; M is selected from the group consisting of Pb, Cu, Ni, Co, Fe, Mn, Cr, Pd, Cd, Yb, Sn, Ge and combinations thereof; and X is Br - , Cl - or I - am) Claim 9 A method for manufacturing a perovskite photodetector according to claim 8, wherein the solvent comprises dimethyl sulfoxide (DMSO), gamma-butyrolactone (γGBL), diethyl sulfoxide, methyl ethyl sulfoxide, pyrrolidone derivatives, amide derivatives, N,N'-dimethylpropyleneurea derivatives, or a combination thereof. Claim 10 delete Claim 11 A method for manufacturing a perovskite photodetector according to claim 1, wherein the antisolvent comprises chlorobenzene, chloroform, hexene, cyclohexene, 1,4-dioxane, benzene, toluene, triethylamine, ethylamine, ethylether, ethyl acetate, acetic acid, 1,2-dichlorobenzene, tert-butyl alcohol, 2-butanol, isopropanol, methylethylketone, or a combination thereof. Claim 12 delete Claim 13 delete Claim 14 A method for manufacturing a perovskite photodetector according to claim 1, comprising the steps of: forming a transparent conductive layer on a substrate; forming a hole transport layer on the transparent conductive layer; forming a photosensitive layer on the hole transport layer; forming an electron transport layer on the photosensitive layer; and forming an electrode on the electron transport layer, wherein the step of forming the photosensitive layer comprises: spin-coating a perovskite precursor solution on a substrate; applying a mixed antisolvent, wherein 1,8-octanedithiol (ODT) is mixed in the antisolvent during spin-coating, onto the substrate; and heat-treating the perovskite layer formed on the substrate. Claim 15 In claim 1, the method comprises the steps of: forming an ITO (Indium Tin Oxide) transparent conductive layer on a glass substrate; forming a PEDOT:PSS hole transport layer on the ITO transparent conductive layer; forming a photosensitive layer on the PEDOT:PSS hole transport layer; forming a PCBM electron transport layer on the photosensitive layer; and forming an AI electrode on the PCBM electron transport layer, wherein the step of forming the photosensitive layer comprises: spin-coating a perovskite precursor solution comprising methylammonium iodide (CH3NH3I), lead(II) oxide (PbI2), dimethyl sulfoxide (DMSO), and γ-butyrolactone (GBL) on a substrate; and applying a mixed antisolvent, comprising chlorobenzene (CB) mixed with 1,8-octanedithiol (ODT), onto the substrate during the spin-coating process. A method for manufacturing a perovskite photodetector, characterized by including the step of heat-treating the perovskite layer formed on the substrate at 80-125 ℃ for 3 to 5 minutes.

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