Light conversion layer, solar cell and power consumption device

Abstract

The present application relates to the technical field of solar cells, and in particular to a light conversion layer, a solar cell, and a power consumption device. The light conversion layer includes a conversion material, and the conversion material includes an upconversion luminescent material and / or a downconversion luminescent material. The light conversion layer is provided on the light incident side of the light absorption layer of the solar cell. Introducing a light conversion layer including an upconversion luminescent material and / or a downconversion luminescent material into a solar cell can absorb photons in the long wavelength band (low energy) and / or short wavelength band (high energy) and convert them to a wavelength band absorbable by the light absorption layer, which is advantageous for increasing the utilization efficiency of the solar spectrum and improving the output performance of the solar cell.

Description

[Technical Field]

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS This application claims priority to a Chinese patent application filed on April 21, 2023, bearing application number 202310431080.5, the entire contents of which are incorporated herein by reference.

[0002] The present application relates to the technical field of solar cells, and in particular to light conversion layers, solar cells and power consuming devices. [Background technology]

[0003] A solar cell is a device that converts light energy directly into electrical energy through the photovoltaic or photochemical effect.

[0004] However, conventional photovoltaic devices limit the efficiency with which solar cells can utilize the solar spectrum. Summary of the Invention [Means for solving the problem]

[0005] The main objective of this application is to provide a light conversion layer for increasing the utilization of the solar spectrum by a solar cell and improving the performance of the solar cell.

[0006] To achieve the above object, the present application provides a light conversion layer, the light conversion layer including a conversion material, the conversion material including an up-conversion luminescent material and / or a down-conversion luminescent material, and the light conversion layer is disposed on the light incident side of the light absorption layer of the solar cell.

[0007] By introducing a light conversion layer containing an upconversion luminescent material and / or a downconversion luminescent material into a solar cell, which is provided on the light incident side of the light absorption layer of the solar cell, it is possible to absorb photons in the long wavelength band (low energy) and / or short wavelength band (high energy) and convert them to a wavelength band that can be absorbed by the light absorption layer, which is advantageous in increasing the utilization rate of the solar light spectrum and improving the output performance of the solar cell.

[0008] Optionally, the solar cell includes an upper electrode, and the light conversion layer is provided on a surface of the upper electrode;

[0009] and / or the solar cell comprises an upper electrode and a first charge transport layer, and the light conversion layer is provided between the upper electrode and the first charge transport layer;

[0010] And / or, the solar cell comprises a first charge transport layer and a light absorbing layer, and the light conversion layer is provided between the first charge transport layer and the light absorbing layer.

[0011] As can be appreciated, the light conversion layer can be disposed on the surface of the upper electrode, between the upper electrode and the first charge transport layer, or between the first charge transport layer and the light absorbing layer.

[0012] Optionally, the solar cell comprises a top electrode, the light conversion layer is the top electrode, and the light conversion layer includes a top electrode material and the conversion material.

[0013] As can be understood, the light conversion layer may be a single layer structure alone or may be compounded with other layer structures in the solar cell, for example, the light conversion layer may be compounded with the upper electrode, so that the upper electrode has the function of the light conversion layer, i.e., the light conversion layer is the upper electrode, and the light conversion layer includes the upper electrode material and the conversion material.

[0014] Optionally, the solar cell comprises a first charge transport layer, and the light conversion layer is a first charge transport layer, and the light conversion layer includes a charge transport material and the conversion material.

[0015] The light conversion layer is composited with the first charge transport layer, the light conversion layer being the first charge transport layer, and the light conversion layer comprising a charge transport material and a conversion material.

[0016] Combining upconversion and / or downconversion luminescent materials with charge transport layer materials can enhance the utilization of the solar spectrum without affecting the intrinsic structural performance of the cell, significantly improving device performance.

[0017] That is, compared with the case where an upconversion layer and / or a downconversion layer and a charge transport layer are separately provided, the provision of a multilayer structure increases the process complexity, requiring additional film fabrication steps, while increasing the number of heterointerfaces and increasing the resistance on the carrier transport path, including the effects of parasitic resistance and interface defects, resulting in a decrease in the photoelectric conversion performance of the device. The photoconversion layer according to the present application (a combination of an upconversion light-emitting material and / or a downconversion light-emitting material and a charge transport layer material) can avoid the above two problems and increase the utilization efficiency of the solar spectrum without changing the inherent physical structure of the cell.

[0018] Optionally, the range of values ​​of the mass of the conversion material relative to the total mass of the materials of the light conversion layer is inclusive of 1% to 75%.

[0019] The conversion material includes an upconversion luminescent material and / or a downconversion luminescent material, and by mixing the conversion material with a charge transport material, a light conversion layer having charge transport and light conversion functions can be obtained, thereby improving the utilization efficiency of the solar spectrum by the solar cell.

[0020] As can be seen, the light conversion layer not only improves the solar spectrum utilization rate through the conversion material therein, but also realizes the charge transport function through the charge transport material. That is, in order to avoid a decrease in photoelectric conversion efficiency, it is necessary to balance the amount of charge transport material and the amount of conversion material used, and to avoid using too little charge transport material in the light conversion layer. As can be seen, photoelectric conversion efficiency is the ratio of the total power output of a battery device under light irradiation to the incident light power. If the amount of charge transport material used in the light conversion layer is too little, the ability to transport electrons or holes through the light conversion layer will be reduced, resulting in low photoelectric conversion efficiency. To avoid a slight improvement in solar spectrum utilization rate, it is also necessary to avoid using too little conversion material in the light conversion layer. To balance solar spectrum utilization rate and photoelectric conversion efficiency, the range of values ​​in which the mass of the conversion material accounts for the total mass of the materials in the light conversion layer includes 1% to 75%.

[0021] Optionally, the range of values ​​of the mass of the conversion material relative to the total mass of the materials of the light conversion layer is inclusively 25% to 60%.

[0022] In order to balance the utilization rate of the solar spectrum and the photoelectric conversion efficiency, the mass of the conversion material accounts for 25% to 60% of the total mass of the materials of the light conversion layer.

[0023] Optionally, the range of thickness of the light conversion layer includes 30 nm to 60 nm.

[0024] For the same material, the thickness of the light conversion layer affects the energy conversion efficiency of the solar cell. For a solar cell to have an adequate energy conversion efficiency, the range of the thickness of the light conversion layer is 30 nm to 60 nm.

[0025] Optionally, the range of thickness of the light conversion layer includes 40 nm to 50 nm.

[0026] For the same material, the thickness of the light conversion layer affects the energy conversion efficiency of the solar cell. For a solar cell to have an adequate energy conversion efficiency, the range of the thickness of the light conversion layer is 40 nm to 50 nm.

[0027] Optionally, the light conversion layer comprises a charge transport material, an upconversion luminescent material, and a downconversion luminescent material, and the mass of the upconversion luminescent material accounts for a range value greater than 0 and less than or equal to 25% of the total mass of materials in the light conversion layer.

[0028] the mass of the down-conversion luminescent material accounts for a range value of more than 0% to 25% of the total mass of the materials of the light conversion layer;

[0029] The mass of the charge transport material accounts for 50% or more and less than 100% of the total mass of the materials in the light conversion layer.

[0030] The conversion material includes an upconversion luminescent material and a downconversion luminescent material, and by mixing the conversion material with a charge transport material, a light conversion layer having charge transport and light conversion functions is obtained, and the light conversion layer can improve the solar spectrum utilization rate of the solar cell. To balance the solar spectrum utilization rate and the photoelectric conversion efficiency, the mass of the upconversion luminescent material relative to the total mass of the materials in the light conversion layer ranges from greater than 0 to 25%, the mass of the downconversion luminescent material relative to the total mass of the materials in the light conversion layer ranges from greater than 0 to 25%, and the mass of the charge transport material relative to the total mass of the materials in the light conversion layer ranges from 50% to 100%.

[0031] Optionally, the conversion material comprises an up-conversion luminescent material, the up-conversion luminescent material comprising at least one of an organic compound or an inorganic compound.

[0032] In the present application, the type of the upconversion luminescent material is not limited as long as the upconversion luminescent material can enhance the utilization efficiency of the solar spectrum, and may be, for example, an organic compound and / or an inorganic compound.

[0033] Optionally, the organic compound comprises at least one of 4CzIPN, thioxanthone, and triphenylamine;

[0034] and / or the inorganic compound is selected from the group consisting of NaYF4, NaLuF4, NaGdF4, NaYbF4, NaYGd, NaYLu, NaYNd, NaGd(WO4)2, LiErF, BaYF5, BaLuF5, BaGdF5, BaYb2F, CaS, LiLa(MoO4)2, Gd2O3, ZrYO, YalO3, CaWO4, and doped with one or more of the rare earth elements Yb, Er, Tm, Eu, Sm, Bi, and Ho. The present invention relates to a method for producing a crystalline silicon dioxide particle, and to a method for producing a crystalline silicon dioxide particle, the method comprising the steps of: (a) providing a crystalline silicon dioxide particle having a thickness of 1000 nm to 1000 nm; (b) providing a crystalline silicon dioxide particle having a thickness of 1000 nm to 1000 nm; and (c) providing a crystalline silicon dioxide particle having a thickness of 1000 nm to 1000 nm.

[0035] In the present application, the upconversion luminescent material is not limited in type, as long as it can enhance the utilization efficiency of the solar spectrum. Examples of the upconversion luminescent material include NaYF, NaLuF, NaGdF, NaYbF, NaYGd, NaYLu, NaYNd, NaGd(WO), LiErF, BaYF, BaLuF, BaGdF, BaYbF, CaS, LiLa(MoO), GdO, ZrYO, YAlO, CaWO, 4CzIPN, and rare earth element-doped NaYF, NaL The upconversion luminescent materials include at least one of uF, NaGdF, NaYbF, NaYGd, NaYLu, NaYNd, NaGd(WO), LiErF, BaYF, BaLuF, BaGdF, BaYbF, CaS, LiLa(MoO), GdO, ZrYO, YAlO, CaWO, 4CzIPN, thioxanthone and derivatives thereof, and triphenylamine and derivatives thereof. The upconversion luminescent materials listed above are merely examples, and the upconversion luminescent material in the present application may further include materials other than those listed above.

[0036] Optionally, the conversion material comprises a down-conversion luminescent material, and the down-conversion luminescent material comprises a fluorescent material and / or a phosphorescent material.

[0037] Optionally, the down-conversion luminescent material comprises a fluorescent material, which comprises at least one of riboflavin, fluorescein-based compounds, rhodamine-based compounds, phycoerythrin, iridium complexes, rare earth element complexes, polyfluorene-based compounds, coumarin-based compounds, naphthalimide-based compounds, polyacene-based compounds, bodipy-based compounds, resorufin-based compounds, pyrazoline-based compounds, triphenylamine-based compounds, carbazole-based compounds, green fluorescent protein, diamine-based fluorescent compounds, perovskite luminescent nanomaterials, and thermally activated delayed fluorescent compounds;

[0038] and / or the down-conversion luminescent material comprises a phosphorescent material, the phosphorescent material comprising a matrix, the matrix comprising at least one of sulfides, oxides, selenides, fluorides, phosphates, silicates and tungstates of Group II metals;

[0039] And / or, the down-conversion luminescent material includes a phosphorescent material, the phosphorescent material includes a matrix and an activator, and the activator includes a heavy metal.

[0040] In the present application, the down-conversion luminescent material is not limited in type, and may be, for example, capable of absorbing photons in a short wavelength band (high energy) and converting them into a visible light wavelength band that can be effectively absorbed by the light absorption layer. The down-conversion luminescent materials listed above are merely examples, and the down-conversion luminescent material in the present application may further include materials other than those listed above.

[0041] Optionally, the charge transport material comprises an electron transport material or a hole transport material.

[0042] Optionally, the electron transport material includes at least one of an imide-based compound, a quinone-based compound, a fullerene and its derivatives, a metal oxide, a semiconductor material oxide, a titanate, and a fluoride.

[0043] Optionally, the imide-based compound includes at least one of phthalimide, succinimide, N-bromosuccinimide, glutarimide, or maleimide;

[0044] and / or the quinone-based compound includes at least one of benzoquinone, naphthoquinone, phenanthrenequinone, or anthraquinone;

[0045] And / or the fullerene and its derivatives are C 60 and PCBM,

[0046] and / or the metal element in the metal oxide comprises at least one of Mg, Cd, Zn, In, Pb, W, Sb, Bi, Hg, Ti, Ag, Mn, Fe, V, Sn, Zr, Sr, Ga, and Cr;

[0047] and / or the semiconductor material oxide comprises silicon oxide;

[0048] and / or the titanate comprises at least one of strontium titanate and calcium titanate;

[0049] And / or, the fluoride includes at least one of lithium fluoride and calcium fluoride.

[0050] The electron transport material has the function of transporting electrons and is used to transport electrons to the corresponding electrode and prevent electrons from diffusing in the opposite direction. In the present application, the electron transport material is not limited and may be any one or more of the materials listed above, or may be a material other than those in the present application.

[0051] For example, the electron transport material includes at least one of imide-based compounds, quinone-based compounds, fullerene and its derivatives, metal oxides, silicon oxide, strontium titanate, calcium titanate, lithium fluoride, and calcium fluoride, but is not limited thereto, and the metal element in the metal oxide includes at least one of Mg, Cd, Zn, In, Pb, W, Sb, Bi, Hg, Ti, Ag, Mn, Fe, V, Sn, Zr, Sr, Ga, and Cr.

[0052] Optionally, the hole transport material comprises at least one of 2,2',7,7'-tetra(N,N-di-p-methoxyphenylamino)-9,9'-spirobifluorene, methoxytriphenylamine-fluoroformamidine, poly[bis(4-phenyl)(2,4,6-trimethylphenyl)amine], poly(3,4-ethylenedioxythiophene), polystyrenesulfonic acid, poly(3-hexylthiophene), triptycene-based triphenylamine, 3,4-ethylenedioxythiophene-methoxytriphenylamine, N-(4-aniline)carbazole-spirobifluorene, polythiophene, a phosphate group monomer, a carbazolyl group monomer, a sulfonic acid group monomer, a triphenylamine group monomer, an aromatic group monomer, a metal oxide, and cuprous thiocyanate, wherein the metal element in the metal oxide comprises at least one of Ni, Mo, and Cu.

[0053] The hole transport material has the function of transporting holes, and is used to transport holes to the corresponding electrode and prevent holes from diffusing in the opposite direction. In the present application, the hole transport material is not limited and may be any one or more of the materials listed above, or may be a material other than those in the present application.

[0054] For example, hole transport materials include, but are not limited to, at least one of 2,2',7,7'-tetra(N,N-di-p-methoxyphenylamino)-9,9'-spirobifluorene, methoxytriphenylamine-fluoroformamidine, poly[bis(4-phenyl)(2,4,6-trimethylphenyl)amine], poly(3,4-ethylenedioxythiophene), polystyrene sulfonic acid, poly(3-hexylthiophene), triptycene-based triphenylamine, 3,4-ethylenedioxythiophene-methoxytriphenylamine, N-(4-aniline)carbazole-spirobifluorene, polythiophene, a phosphate group monomer, a carbazolyl group monomer, a sulfonic acid group monomer, a triphenylamine group monomer, an aromatic group monomer, a metal oxide, and cuprous thiocyanate, wherein the metal element in the metal oxide includes at least one of Ni, Mo, and Cu.

[0055] The present application further provides a solar cell comprising the light conversion layer.

[0056] Optionally, along a first direction, the solar cell sequentially comprises an upper electrode, a first charge transport layer, a light absorbing layer, a second charge transport layer, and a lower electrode;

[0057] the first charge transport layer includes the light conversion layer, and the charge transport material in the first charge transport layer includes one of an electron transport material and a hole transport material;

[0058] The charge transport material in the second charge transport layer includes the other of an electron transport material and a hole transport material.

[0059] By introducing an upconversion luminescent material and / or a downconversion luminescent material into the first charge transport layer, photons in the long wavelength band (low energy) and / or short wavelength band (high energy) can be absorbed and converted into a wavelength band that can be absorbed by the light absorption layer, which is advantageous in increasing the utilization efficiency of the solar spectrum and improving the output performance of the solar cell.

[0060] Optionally, the material of the upper electrode and / or the lower electrode comprises an organic conductive material and / or an inorganic conductive material.

[0061] Optionally, the organic conductive material comprises at least one of poly(3,4-ethylenedioxythiophene), polythiophene, and polyacetylene;

[0062] and / or the inorganic conductive material includes at least one of fluorine-doped SnO2 transparent conductive glass, aluminum-doped zinc oxide transparent conductive glass, and metal.

[0063] In the present application, the materials for the upper electrode and the lower electrode are not specifically limited in type, and may be any material that can provide a conductive function, and may be organic conductive materials such as conductive polymers (poly(3,4-ethylenedioxythiophene), polythiophene, polyacetylene, etc.), or inorganic conductive materials such as transparent conductive oxides (FTO, ITO, AZO, etc.), metals, carbon derivatives, etc.

[0064] Optionally, the material of the light absorbing layer includes a perovskite, and the structural formula of the perovskite is ABX3, where A is an inorganic cation and / or an organic anion, B is an inorganic cation and / or an organic cation, and X is an inorganic anion and / or an organic anion.

[0065] In the present application, the material of the light absorbing layer is not limited. Preferably, the material of the light absorbing layer includes perovskite, and the structural formula of the perovskite is ABX3, where A is an inorganic cation and / or an organic anion, B is an inorganic cation and / or an organic cation, and X is an inorganic anion and / or an organic anion.

[0066] Perovskite materials are a broad group of materials that typically have an ABX3 structure, e.g., where the A site is Cs + , CH3NH2 + and CH2(NH2) + and the B site is Pb 2+ or Sn2+ and the X site is a halogen ion Cl - , Br - and I - It is a cubic close-packed structure formed by hydrogen bonding between the halide octahedron BX6 and the A-site cations. Organic-inorganic hybrid lead halide perovskites with this structure have advantages such as low cost, high internal absorption coefficient for visible light, high carrier mobility, tunable band gap, and ease of synthesis by solution processing.

[0067] The present application further provides a power consuming device comprising the solar cell.

[0068] The light conversion layer of the present application includes a conversion material, and the conversion material includes an upconversion luminescent material and / or a downconversion luminescent material. By introducing the upconversion luminescent material and / or the downconversion luminescent material into the light conversion layer, photons in the long wavelength band (low energy) and / or the short wavelength band (high energy) can be absorbed and converted into a wavelength band that can be absorbed by the light absorption layer, which is advantageous in increasing the utilization efficiency of the solar spectrum and improving the output performance of the solar cell. [Brief explanation of the drawings]

[0069] In order to more clearly explain the technical solutions in the embodiments of the present application or the prior art, the following briefly introduces drawings necessary for explaining the embodiments or the prior art. Obviously, the drawings described below are only some embodiments of the present application, and those skilled in the art can obtain other drawings based on the structures shown in these drawings without any creative efforts.

[0070] [Figure 1] 1 is a structural schematic diagram of a solar cell according to an embodiment of the present application;

[0071] [Table 1A]

[0072] The achievement of the objects, functional features and advantages of the present application will be further explained with reference to the accompanying drawings in conjunction with the examples. DETAILED DESCRIPTION OF THE INVENTION

[0073] The technical solutions in this application will be clearly and completely described below in conjunction with the drawings in the examples of this application, but obviously, the described examples are only a part of the examples of this application, not all of the examples. Based on the embodiments of this application, all other embodiments that a person skilled in the art can obtain without any creative efforts belong to the protection scope of this application.

[0074] Hereinafter, embodiments specifically disclosing the solar cell of the present application will be described in detail with appropriate reference to the drawings. However, unnecessary detailed description may be omitted. For example, detailed description of well-known matters and redundant description of actually identical structures may be omitted. This is to avoid unnecessary redundancy in the following description and to facilitate understanding by those skilled in the art. Note that the accompanying drawings and the following description are provided to enable those skilled in the art to fully understand the present disclosure and are not intended to limit the subject matter recited in the claims.

[0075] The "ranges" disclosed in this application are defined in the form of lower and upper limits, and a given range is defined by selecting one lower limit and one upper limit, and the selected lower and upper limits define the boundaries of the particular range. Such defined ranges may be inclusive or exclusive of the end values, and are arbitrarily combinable; i.e., any lower limit can be combined with any upper limit to form a single range. For example, if ranges of 60 to 120 and 80 to 110 are listed for a particular parameter, it is understood that ranges of 60 to 110 and 80 to 120 are also contemplated. Furthermore, if 1 and 2 are listed as minimum range values ​​and 3, 4, and 5 are listed as maximum range values, the following ranges are also contemplated: 1 to 3, 1 to 4, 1 to 5, 2 to 3, 2 to 4, and 2 to 5. In this application, unless otherwise specified, a numerical range "a to b" represents a shorthand notation for any combination of real numbers a to b, where a and b are both real numbers. For example, the numerical range "0-5" indicates that this specification has already listed all real numbers between "0-5," and "0-5" is merely a shorthand representation of combinations of these numbers. Also, expressing a parameter as an integer ≧2 is equivalent to disclosing that this parameter is, for example, the integers 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, etc.

[0076] Unless otherwise stated, all the embodiments and optional embodiments in the present application can be combined with each other to form a new technical solution.

[0077] Unless otherwise stated, all technical features and optional technical features of the present application can be combined with each other to form a new technical solution.

[0078] Unless otherwise specified, all steps in the present application may be performed in order or randomly, and are preferably performed in order. For example, when the method includes steps (a) and (b), it means that the method may include steps (a) and (b) performed in order, or may include steps (b) and (a) performed in order. For example, when the method mentioned above may further include step (c), it means that step (c) may be added to the method in any order, and for example, the method may include steps (a), (b), and (c), or may include steps (a), (c), and (b), or may include steps (c), (a), and (b), etc.

[0079] Conventional photovoltaic devices limit the efficiency with which solar cells can utilize the solar spectrum.

[0080] For example, the optical band gap of the light-absorbing layer material (such as perovskite) in conventional photovoltaic devices is fixed. The optical band gap is the energy barrier for electron transitions in a material when light interacts with the material, and is determined by the energy band structure of the material itself. Electrons must absorb the energy of photons to cross this band gap and reach an excited state. Because the absorption spectrum of the light-absorbing layer material is fixed, long-wavelength bands are directly transmitted through the light-absorbing layer, preventing full utilization of the solar spectrum. Short-wavelength bands are absorbed by the light-absorbing layer but cause significant damage to the material. For example, ultraviolet light has high optical energy and activity, so MAPbI3 (MA = CH3NH3 + ) MA in perovskites + and I - It can directly catalyze the oxidation-reduction reaction with iodine to produce elemental iodine and methylamine gas, causing destruction of the crystal lattice and aging of the film.

[0081] In order to improve the utilization efficiency of the solar spectrum by a solar cell, the present application provides a light conversion layer, which includes a conversion material, and the conversion material includes an up-conversion luminescent material and / or a down-conversion luminescent material, and the light conversion layer is disposed on the light incident side of the light absorption layer of the solar cell.

[0082] Upconversion luminescence refers to the luminescence process in which high-energy light (short wavelength) is emitted through various conversion methods under the excitation of low-energy light (long wavelength).

[0083] For upconversion luminescent materials, the material is excited with low energy light and emits high energy light, i.e., when excited with long wavelength, low frequency light, it emits short wavelength, high frequency light.

[0084] In down-conversion luminescence, after being excited by high-energy (short-wavelength) light, low-energy (long-wavelength) light is emitted, and this luminescence method is also called down-conversion luminescence.

[0085] For down-conversion luminescent materials, the optically active substance emits low-energy photons under the excitation of high-energy photons. Down-conversion luminescent materials refer to materials that can absorb high-energy photon ultraviolet light and then emit one or more low-energy photons.

[0086] Regarding the light-absorbing layer, the light-absorbing layer includes a light-absorbing material, which is a material having a photoelectric conversion function, and the light-absorbing material absorbs photons of sunlight to generate excitations, which excite electrons in the valence band to generate photogenerated hole-electron pairs.

[0087] Providing a light conversion layer on the light incident side of a light absorption layer of a solar cell means that the light conversion layer is provided on the side where light is incident on the light absorption layer.

[0088] By introducing a light conversion layer containing an upconversion luminescent material and / or a downconversion luminescent material into a solar cell, it is possible to absorb photons in the long wavelength band (low energy) and / or short wavelength band (high energy) and convert them to a wavelength band that can be absorbed by the light absorption layer, which is advantageous in increasing the utilization rate of the solar spectrum and improving the output performance of the solar cell.

[0089] In one embodiment, the solar cell comprises an upper electrode, and the light conversion layer is provided on a surface of the upper electrode, and / or the solar cell comprises an upper electrode and a first charge transport layer, and the light conversion layer is provided between the upper electrode and the first charge transport layer, and / or the solar cell comprises the first charge transport layer and a light absorption layer, and the light conversion layer is provided between the first charge transport layer and the light absorption layer.

[0090] As shown in FIG. 1, which is a structural schematic diagram of a solar cell according to an embodiment, the solar cell is provided with an upper electrode 1, a first charge transport layer 2, a light absorption layer 3, a second charge transport layer 4, and a lower electrode 5 in this order from top to bottom.

[0091] As for the electrode, the electrode is mainly used to collect electrons / holes from the charge transport layer.

[0092] Regarding the light-absorbing layer, the light-absorbing layer includes a light-absorbing material, which is a material having a photoelectric conversion function, and the light-absorbing material absorbs photons of sunlight to generate excitations, which excite electrons in the valence band to generate photogenerated hole-electron pairs.

[0093] Regarding the charge transport layer, as shown in Figure 1, which is a structural schematic diagram of a solar cell, the first charge transport layer 2 is located between the electrode and the light absorption layer. It is a layered structure for transporting electrons or holes, and is made of an electron or hole transporting material, which is used to transport electrons to the corresponding electrode and prevent the diffusion of electrons or holes in the opposite direction.

[0094] As can be appreciated, the light conversion layer can be disposed on the surface of the upper electrode, between the upper electrode and the first charge transport layer, or between the first charge transport layer and the light absorbing layer.

[0095] In one embodiment, the solar cell comprises a top electrode, the light conversion layer is the top electrode, and the light conversion layer includes a top electrode material and a conversion material.

[0096] As can be understood, the light conversion layer may be a single layer structure alone or may be compounded with other layer structures in the solar cell, for example, the light conversion layer may be compounded with the upper electrode, so that the upper electrode has the function of the light conversion layer, i.e., the light conversion layer is the upper electrode, and the light conversion layer includes the upper electrode material and the conversion material.

[0097] In one embodiment, the solar cell comprises a first charge transport layer, and the light conversion layer is the first charge transport layer, and the light conversion layer comprises a charge transport material and a conversion material.

[0098] The light conversion layer is composited with the first charge transport layer, the light conversion layer being the first charge transport layer, and the light conversion layer comprising a charge transport material and a conversion material.

[0099] By introducing an upconversion luminescent material and / or a downconversion luminescent material into the first charge transport layer, photons in the long wavelength band (low energy) and / or short wavelength band (high energy) can be absorbed and converted into a wavelength band that can be absorbed by the light absorption layer, which is advantageous in increasing the utilization efficiency of the solar spectrum and improving the output performance of the solar cell.

[0100] Furthermore, by combining upconversion and / or downconversion luminescent materials with charge transport layer materials, the solar spectrum can be utilized more efficiently without affecting the intrinsic structural performance of the cell, significantly improving device performance.

[0101] That is, compared with the case where an upconversion layer and / or a downconversion layer and a charge transport layer are separately provided, the provision of a multilayer structure increases the process complexity, requiring additional film fabrication steps, while increasing the number of heterointerfaces and increasing the resistance on the carrier transport path, including the effects of parasitic resistance and interface defects, resulting in a decrease in the photoelectric conversion performance of the device. The photoconversion layer according to the present application (a combination of an upconversion light-emitting material and / or a downconversion light-emitting material and a charge transport layer material) can avoid the above two problems and increase the utilization efficiency of the solar spectrum without changing the inherent physical structure of the cell.

[0102] The photovoltaic principle of perovskite solar cells is that sunlight enters the device through the transparent conductive glass, passes through the electron transport layer, and reaches the perovskite active layer, where it is absorbed and excites electrons in the valence band to generate photogenerated hole-electron pairs. Under the action of the internal electric field, the hole and electron charges are separated, and the photogenerated electrons move to the electron transport layer and are then collected by the electrode. At the same time, the holes in the perovskite layer are transported to the hole transport layer and then conducted to the electrode. The electrons and holes then drive a load via an external circuit.

[0103] In one embodiment, the range of values ​​for the mass of the conversion material relative to the total mass of the materials in the light conversion layer includes 1% to 75%.

[0104] The conversion material includes an upconversion luminescent material and / or a downconversion luminescent material, and by mixing the conversion material with a charge transport material, a light conversion layer having charge transport and light conversion functions can be obtained, thereby improving the utilization efficiency of the solar spectrum by the solar cell.

[0105] As can be seen, the light conversion layer not only improves the utilization of the solar spectrum through the conversion material therein, but also realizes the charge transport function through the charge transport material. That is, to avoid a decrease in photoelectric conversion efficiency, it is necessary to balance the amount of charge transport material and the amount of conversion material used, and to avoid using too little charge transport material in the light conversion layer. As can be seen, photoelectric conversion efficiency is the ratio of the total power output of a battery device under light irradiation to the incident light power. If the amount of charge transport material used in the light conversion layer is too little, the ability to transport electrons or holes through the light conversion layer will be reduced, resulting in low photoelectric conversion efficiency. To avoid a slight improvement in solar spectrum utilization, it is also necessary to avoid using too little conversion material in the light conversion layer. To balance the utilization of the solar spectrum and photoelectric conversion efficiency, the range of values ​​in which the mass of the conversion material accounts for the total mass of the materials in the light conversion layer includes 1% to 75%.

[0106] In the above range of 1% to 75%, the values ​​include the minimum and maximum values ​​of this range, and each value between such minimum and maximum values. Specific examples include, but are not limited to, the point values ​​in the examples, as well as 1%, 10%, 15%, 20%, 25%, 30%, 35%, 40%, 45%, 50%, 55%, 60%, 65%, 70%, 75%, etc., and range values ​​between any two of the above point values.

[0107] In one embodiment, the range of values ​​for the weight of the conversion material relative to the total weight of the materials in the charge transport layer includes 25% to 60%.

[0108] The conversion material includes an up-conversion luminescent material and / or a down-conversion luminescent material, and by incorporating the conversion material into the light conversion layer, the utilization of the solar spectrum by the solar cell can be improved.

[0109] As can be appreciated, the light conversion layer can be a mixture of an upconversion luminescent material and a charge transport layer material, a mixture of a downconversion luminescent material and a charge transport layer material, or a mixture of an upconversion luminescent material, a downconversion luminescent material, and a charge transport layer material.

[0110] To balance the utilization rate of the solar spectrum and the photoelectric conversion efficiency, the mass of the conversion material accounts for 25% to 60% of the total mass of the materials in the light conversion layer.

[0111] In the above range of 25% to 60%, the values ​​include the minimum and maximum values ​​of this range, and each value between such minimum and maximum values. Specific examples include, but are not limited to, the point values ​​in the examples, as well as 25%, 26%, 28%, 30%, 35%, 40%, 45%, 50%, 55%, 60%, etc., and range values ​​between any two of the above point values.

[0112] In one embodiment, the range of thicknesses for the charge transport layer includes 30 nm to 60 nm.

[0113] For the same material, the thickness of the light conversion layer affects the energy conversion efficiency of the solar cell. For a solar cell to have an adequate energy conversion efficiency, the range of the thickness of the light conversion layer is 30 nm to 60 nm.

[0114] In the above range of 30 nm to 60 nm, the values ​​include the minimum and maximum values ​​of this range, and each value between such minimum and maximum values. Specific examples include, but are not limited to, the point values ​​in the examples, as well as 30 nm, 35 nm, 40 nm, 45 nm, 50 nm, 55 nm, 60 nm, etc., and range values ​​between any two of the above point values.

[0115] In one embodiment, the range of thickness values ​​for the light conversion layer includes 40 nm to 50 nm.

[0116] In order for the solar cell to have suitable energy conversion efficiency, the range value of the thickness of the light conversion layer includes 40 nm to 50 nm.

[0117] In the above range of 40 nm to 50 nm, the values ​​include the minimum and maximum values ​​of this range, and each value between such minimum and maximum values. Specific examples include, but are not limited to, the point values ​​in the examples, as well as 40 nm, 42 nm, 44 nm, 45 nm, 47 nm, 49 nm, 50 nm, etc., and range values ​​between any two of the above point values.

[0118] In one embodiment, the light conversion layer includes a charge transport material, an upconversion luminescent material, and a downconversion luminescent material, wherein the mass of the upconversion luminescent material is greater than 0 and less than 25% of the total mass of the materials of the light conversion layer, the mass of the downconversion luminescent material is greater than 0 and less than 25%, and the mass of the charge transport material is greater than 50% and less than 100% of the total mass of the materials of the light conversion layer.

[0119] The conversion material includes an upconversion luminescent material and a downconversion luminescent material, and by mixing the conversion material with a charge transport material, a light conversion layer having charge transport and light conversion functions is obtained, and the light conversion layer can improve the solar spectrum utilization rate of the solar cell. To balance the solar spectrum utilization rate and the photoelectric conversion efficiency, the mass of the upconversion luminescent material relative to the total mass of the materials in the light conversion layer ranges from greater than 0 to 25%, the mass of the downconversion luminescent material relative to the total mass of the materials in the light conversion layer ranges from greater than 0 to 25%, and the mass of the charge transport material relative to the total mass of the materials in the light conversion layer ranges from 50% to 100%.

[0120] The range value for the mass of the upconversion luminescent material relative to the total mass of the materials in the light conversion layer is greater than 0 and less than or equal to 25%, including 0.5%, 1%, 5%, 10%, 15%, 20%, 25%, etc., and range values ​​between any two of the above point values.

[0121] The range value of the mass of the down-conversion luminescent material relative to the total mass of the materials in the light conversion layer is greater than 0 and less than or equal to 25%, including 0.5%, 5%, 10%, 15%, 20%, 25%, etc., and range values ​​between any two of the above point values.

[0122] The range of values ​​for the mass of the charge transport material relative to the total mass of the materials in the light conversion layer is 50% or more and less than 100%, including 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85%, 90%, 95%, 99%, etc., and range values ​​between any two of the above mentioned point values.

[0123] In one embodiment, the conversion material comprises an upconversion luminescent material, which comprises at least one of an organic compound or an inorganic compound.

[0124] In the present application, the type of the upconversion luminescent material is not limited as long as the upconversion luminescent material can enhance the utilization efficiency of the solar spectrum, and may be, for example, an organic compound and / or an inorganic compound.

[0125] In one embodiment, the organic compound includes at least one of 4CzIPN, thioxanthone, and triphenylamine, and the inorganic compound includes NaYF4, NaLuF4, NaGdF4, NaYbF4, NaYGd, NaYLu, NaYNd, NaGd(WO4)2, LiErF, BaYF5, BaLuF5, BaGdF5, BaYb2F, CaS, LiLa(MoO4)2, Gd2O3, ZrYO, YAlO3, CaWO4, and at least one of NaYF4, NaLuF4, NaGdF4, NaYbF4, NaYGd, NaYLu, NaYNd, NaGd(WO4)2, LiErF, BaYF5, BaLuF5, BaGdF5, BaYb2F, CaS, LiLa(MoO4)2, Gd2O3, ZrYO, YAlO3, and CaWO4 doped with one or more of Yb, Er, Tm, Eu, Sm, Bi, and Ho rare earth elements.

[0126] In the present application, the upconversion luminescent material is not limited in type, as long as it can enhance the utilization efficiency of the solar spectrum, and examples thereof include NaYF4, NaLuF4, NaGdF4, NaYbF4, NaYGd, NaYLu, NaYNd, NaGd(WO4)2, LiErF, BaYF5, BaLuF5, BaGdF5, BaYb2F, CaS, LiLa(MoO4)2, Gd2O3, ZrYO, YAlO3, CaWO4, 4CzIPN, and rare earth element-doped NaYF4, The upconversion luminescent materials in the present application include at least one of NaLuF4, NaGdF4, NaYbF4, NaYGd, NaYLu, NaYNd, NaGd(WO4)2, LiErF, BaYF5, BaLuF5, BaGdF5, BaYb2F, CaS, LiLa(MoO4)2, Gd2O3, ZrYO, YAlO3, CaWO4, thioxanthone and derivatives thereof, and triphenylamine and derivatives thereof. The upconversion luminescent materials listed above are merely examples, and the upconversion luminescent material in the present application may further include materials other than those listed above.

[0127] In one embodiment, the conversion material comprises a down-converting luminescent material, which comprises a fluorescent material and / or a phosphorescent material.

[0128] Under ultraviolet irradiation, the fluorescent material emits visible light of various colors depending on the type and content of metals and activators in the pigment.

[0129] Phosphorescent materials are materials that can emit phosphorescence when excited by electromagnetic radiation and ion beams. Phosphorescence is a slow-emission photoluminescence phenomenon. When a room-temperature material is irradiated with incident light of a certain wavelength (usually ultraviolet or X-ray), the material absorbs the light energy, enters an excited state (usually with a different spin multiplicity than the ground state), and then slowly de-excites, emitting outgoing light (usually in the visible wavelength range) with a wavelength longer than the incident light wavelength.

[0130] In one embodiment, the down-conversion luminescent material comprises a fluorescent material, the fluorescent material comprising at least one of riboflavin, fluorescein-based compounds, rhodamine-based compounds, phycoerythrin, iridium complexes, rare earth element complexes, polyfluorene-based compounds, coumarin-based compounds, naphthalimide-based compounds, polyacene-based compounds, bodipy-based compounds, resorufin-based compounds, pyrazoline-based compounds, triphenylamine-based compounds, carbazole-based compounds, green fluorescent proteins, diamine-based fluorescent compounds, perovskite luminescent nanomaterials, and thermally activated delayed fluorescent compounds; and / or the down-conversion luminescent material comprises a phosphorescent material, the phosphorescent material comprising a matrix, the matrix comprising at least one of sulfides, oxides, selenides, fluorides, phosphates, silicates, and tungstates of Group II metals; and / or the down-conversion luminescent material comprises a phosphorescent material, the phosphorescent material comprising a matrix and an activator, the activator comprising a heavy metal.

[0131] In the present application, the down-conversion luminescent material is not limited in type and may be any of the materials mentioned in the present application or any materials not mentioned in the present application, as long as it can absorb photons in a short wavelength band (high energy) and convert them into a visible light wavelength band that can be effectively absorbed by the light absorption layer. For example, the down-conversion luminescent material may include a fluorescent material and / or a phosphorescent material, and the fluorescent material may include riboflavin, fluorescein-based compounds (including fluorescein isothiocyanate), rhodamine-based compounds (including tetraethyl rhodamine, tetramethyl isothiocyanate rhodamine, etc.). ), phycoerythrin, iridium complexes, rare earth element complexes (including trivalent rare earth lanthanide chelates), polyfluorene-based compounds, coumarin-based compounds, naphthalimide-based compounds, polyacene-based compounds (including triacenes and tetraacenes), bodipy-based compounds, resorufin-based compounds, pyrazoline-based compounds, triphenylamine-based compounds, carbazole-based compounds, green fluorescent proteins, diamine-based fluorescent compounds, perovskite luminescent nanomaterials, and thermally activated delayed fluorescent compounds (including 2,3,5,6-tetra(9-carbazolyl)-terephthalonitrile (4CzTPN)).

[0132] The phosphorescent material includes a matrix and an activator, where the matrix includes at least one of sulfides, oxides, selenides, fluorides, phosphates, silicates, and tungstates of Group II metals, and the activator includes a heavy metal. For example, the matrix includes ZnS, BaS, CaS, CaWO3, Ca3(PO4)2, Zn2SiO4, and Y3SiO3. Heavy metals used as activators include Au, Cu, Mn, Ag, Bi, Pb, and rare earth metals.

[0133] Thermally activated delayed fluorescence (TADF) compounds can emit fluorescence when excitons completely return from the triplet state to the singlet state under thermal disturbance, and this fluorescence is called TADF (Thermally Activated Delayed Fluorescence).

[0134] The main light-emitting mechanism is that the energy difference between the singlet and triplet states of TADF materials is small, which is advantageous for triplet excitons to reach the singlet state through an efficient reverse intersystem crossing process, form singlet excitons, and emit light by radiative transition.

[0135] In one embodiment, the charge transport material comprises an electron transport material or a hole transport material.

[0136] The electron transport material has the function of transporting electrons and is used to transport electrons to the corresponding electrode and to prevent electron diffusion in the opposite direction.

[0137] The hole transport material has the function of transporting holes and is used to transport holes to the corresponding electrode and to prevent holes from diffusing in the opposite direction.

[0138] In one embodiment, the electron transport material includes at least one of imide-based compounds, quinone-based compounds, fullerenes and their derivatives, metal oxides, semiconductor material oxides, titanates, and fluorides.

[0139] In one embodiment, the imide-based compound includes at least one of phthalimide, succinimide, N-bromosuccinimide, glutarimide, or maleimide, and / or the quinone-based compound includes at least one of benzoquinone, naphthoquinone, phenanthrenequinone, or anthraquinone, and / or the fullerene and its derivatives are C 60 , PCBM ([6,6]-phenyl-C61-butyric acid methyl ester), and / or the metal element in the metal oxide comprises at least one of Mg, Cd, Zn, In, Pb, W, Sb, Bi, Hg, Ti, Ag, Mn, Fe, V, Sn, Zr, Sr, Ga and Cr, and / or the semiconductor material oxide comprises silicon oxide, and / or the titanate comprises at least one of strontium titanate and calcium titanate, and / or the fluoride comprises at least one of lithium fluoride and calcium fluoride.

[0140] The electron transport material has the function of transporting electrons and is used to transport electrons to the corresponding electrode and prevent electrons from diffusing in the opposite direction. In the present application, the electron transport material is not limited and may be any one or more of the materials listed above, or may be a material other than those in the present application.

[0141] For example, the electron transport material includes at least one of imide-based compounds, quinone-based compounds, fullerene and its derivatives, metal oxides, silicon oxides, strontium titanate, calcium titanate, lithium fluoride, and calcium fluoride, and the metal element in the metal oxide includes at least one of Mg, Cd, Zn, In, Pb, W, Sb, Bi, Hg, Ti, Ag, Mn, Fe, V, Sn, Zr, Sr, Ga, and Cr.

[0142] In one embodiment, the hole transport material comprises at least one of 2,2′,7,7′-tetra(N,N-di-p-methoxyphenylamino)-9,9′-spirobifluorene, methoxytriphenylamine-fluoroformamidine, poly[bis(4-phenyl)(2,4,6-trimethylphenyl)amine], poly(3,4-ethylenedioxythiophene), polystyrene sulfonic acid, poly(3-hexylthiophene), triptycene-based triphenylamine, 3,4-ethylenedioxythiophene-methoxytriphenylamine, N-(4-aniline)carbazole-spirobifluorene, polythiophene, a phosphate group molecule, a carbazolyl group molecule, a sulfonate group molecule, a triphenylamine group molecule, an aromatic group molecule, a metal oxide, and cuprous thiocyanate, wherein the metal element in the metal oxide comprises at least one of Ni, Mo, and Cu.

[0143] The hole transport material has the function of transporting holes, and is used to transport holes to the corresponding electrode and prevent holes from diffusing in the opposite direction. In the present application, the hole transport material is not limited and may be any one or more of the materials listed above, or may be a material other than those in the present application.

[0144] In one embodiment, the hole transport material includes, but is not limited to, at least one of 2,2',7,7'-tetra(N,N-di-p-methoxyphenylamino)-9,9'-spirobifluorene, methoxytriphenylamine-fluoroformamidine, poly[bis(4-phenyl)(2,4,6-trimethylphenyl)amine], poly(3,4-ethylenedioxythiophene), polystyrene sulfonic acid, poly(3-hexylthiophene), triptycene-based triphenylamine, 3,4-ethylenedioxythiophene-methoxytriphenylamine, N-(4-aniline)carbazole-spirobifluorene, polythiophene, a phosphate group monomer, a carbazolyl group monomer, a sulfonate group monomer, a triphenylamine group monomer, an aromatic group monomer, a metal oxide, and cuprous thiocyanate, wherein the metal element in the metal oxide includes at least one of Ni, Mo, and Cu.

[0145] In one embodiment, the present application further provides a solar cell comprising the above-described light conversion layer.

[0146] The light conversion layer adopts all the technical solutions of all the above embodiments, and therefore has at least all the beneficial effects of the technical solutions of the above embodiments, and they will not be described one by one here.

[0147] By adopting a solar cell having the above-mentioned light conversion layer and introducing an upconversion luminescent material and / or a downconversion luminescent material into the light conversion layer, it is possible to absorb photons in the long wavelength band (low energy) and / or short wavelength band (high energy) and convert them into a wavelength band that can be absorbed by the light absorption layer, which is advantageous in increasing the utilization rate of the solar spectrum and improving the output performance of the solar cell.

[0148] In one embodiment, the solar cell comprises, along a first direction, an upper electrode, a first charge transport layer, a light absorption layer, a second charge transport layer, and a lower electrode in that order, the first charge transport layer includes the above-mentioned light conversion layer, the charge transport material in the first charge transport layer includes one of an electron transport material and a hole transport material, and the charge transport material in the second charge transport layer includes the other of the electron transport material and the hole transport material.

[0149] As for the electrode, the electrode is mainly used to collect electrons / holes from the charge transport layer.

[0150] Regarding the light-absorbing layer, the light-absorbing layer includes a light-absorbing material, which is a material having a photoelectric conversion function, and the light-absorbing material absorbs photons of sunlight to generate excitations, which excite electrons in the valence band to generate photogenerated hole-electron pairs.

[0151] FIG. 1 shows a schematic diagram of the structure of a solar cell according to one embodiment. The solar cell is sequentially provided with, from top to bottom, an upper electrode 1, a first charge transport layer 2, a light absorbing layer 3, a second charge transport layer 4, and a lower electrode 5. By introducing an upconversion luminescent material and / or a downconversion luminescent material into the first charge transport layer, photons in the long wavelength band (low energy) and / or short wavelength band (high energy) can be absorbed and converted into a wavelength band that can be absorbed by the light absorbing layer, which is advantageous for increasing the utilization efficiency of the solar spectrum and improving the output performance of the solar cell.

[0152] In one embodiment, the material of the top electrode and / or the bottom electrode includes an organic conductive material and / or an inorganic conductive material.

[0153] In one embodiment, the organic conductive material includes at least one of poly(3,4-ethylenedioxythiophene), polythiophene, and polyacetylene, and / or the inorganic conductive material includes at least one of fluorine-doped SnO transparent conductive glass, aluminum-doped zinc oxide transparent conductive glass, and a metal.

[0154] In the present application, the materials for the upper electrode and the lower electrode are not specifically limited in type, and may be any material that can provide a conductive function, and may be organic conductive materials such as conductive polymers (poly(3,4-ethylenedioxythiophene), polythiophene, polyacetylene, etc.), or inorganic conductive materials such as transparent conductive oxides (FTO, ITO, AZO, etc.), metals, carbon derivatives, etc.

[0155] FTO conductive glass is a fluorine-doped SnO2 transparent conductive glass (SnO2:F) and is abbreviated as FTO. ITO conductive glass is made by plating a layer of indium tin oxide (commonly known as ITO) film onto a soda-lime or boron-silicon substrate glass using magnetron sputtering. AZO is an abbreviation for aluminum-doped zinc oxide (ZnO) transparent conductive glass.

[0156] In one embodiment, the material of the light absorbing layer comprises a perovskite, and the structural formula of the perovskite is ABX3, where A is an inorganic cation and / or an organic anion, B is an inorganic cation and / or an organic cation, and X is an inorganic anion and / or an organic anion.

[0157] In the present application, the material of the light absorbing layer is not limited. Preferably, the material of the light absorbing layer includes perovskite, and the structural formula of the perovskite is ABX3, where A is an inorganic cation and / or an organic anion, B is an inorganic cation and / or an organic cation, and X is an inorganic anion and / or an organic anion.

[0158] For example, A is an inorganic cation, or an organic cation, or a mixture of inorganic and organic cations; B is an inorganic cation, or an organic cation, or a mixture of inorganic and organic cations; and X is an inorganic cation, or an organic cation, or a mixture of inorganic and organic cations.

[0159] Perovskite materials are a broad group of materials that typically have an ABX3 structure, e.g., where the A site is Cs +, CH3NH2 + and CH2(NH2) + and the B site is Pb 2+ or Sn 2+ and the X site is a halogen ion Cl - , Br - and I - It is a cubic close-packed structure formed by hydrogen bonding between the halide octahedron BX6 and the A-site cations. Organic-inorganic hybrid lead halide perovskites with this structure have advantages such as low cost, high internal absorption coefficient for visible light, high carrier mobility, tunable band gap, and ease of synthesis by solution processing.

[0160] As can be seen, perovskite materials with a fixed composition have a fixed optical bandgap and are unable to fully utilize the solar spectrum; the long-wavelength band is directly transmitted through the light-absorbing layer; by introducing an upconversion luminescent material and / or a downconversion luminescent material, photons in the short-wavelength band and / or long-wavelength band can be absorbed and converted into visible light wavelength bands that can be effectively absorbed by the perovskite, thereby increasing the utilization of the solar spectrum and improving the current level of the device. Furthermore, by directly integrating the upconversion luminescent material and / or the downconversion luminescent material into the first charge transport layer, process complexity can be reduced, the number of interfaces can be reduced, and the inherent structural advantages of the device can be ensured.

[0161] In one embodiment, methods for fabricating the top electrode, the first charge transport layer, the light absorbing layer, the second charge transport layer, and the bottom electrode include chemical bath deposition, electrochemical deposition, chemical vapor deposition, physical epitaxial growth, thermal co-evaporation, atomic layer deposition, magnetron sputtering, precursor liquid spin coating, precursor liquid slit coating, precursor liquid scraping, and mechanical bonding.

[0162] In the process of manufacturing a solar cell, the manufacturing method of each layer is not limited, and may be, for example, a chemical bath deposition method, an electrochemical deposition method, a chemical vapor deposition method, a physical epitaxial growth method, a thermal co-evaporation method, an atomic layer deposition method, a magnetron sputtering method, a precursor liquid spin coating method, a precursor liquid slit coating method, a precursor liquid scraping method, or a mechanical pressing method.

[0163] In chemical bath deposition, chemical bath deposition is a technique in which a chemical reaction occurs in the liquid phase, followed by deposition onto a substrate.

[0164] In electrochemical deposition, electrochemical deposition refers to a technique in which an electric current is generated by the movement of positive and negative ions in an electrolyte solution under the action of an external electric field, and an oxidation-reduction reaction occurs on the electrode, accompanied by the exchange of electrons, to form a plating layer.

[0165] Chemical vapor deposition is a process in which gaseous or vaporous substances react in the gas phase or at a gas-solid interface to produce a solid deposit.

[0166] In physical epitaxial growth, epitaxial growth refers to growing a single-crystal layer on a single-crystal substrate (base) that meets certain requirements and follows the same crystal orientation as the substrate, so that the original crystal extends outward a certain distance.

[0167] Atomic layer deposition is a film formation technique that uses sequential chemical reactions in the gas phase.

[0168] In magnetron sputtering, argon ions are accelerated by a cathode and collide with the cathode target surface, sputtering atoms from the target surface and depositing them on the substrate surface to form a film.

[0169] The precursor liquid spin coating method is an abbreviation for spin coating, and the main equipment used is a spin coater. The spin coating method involves three steps: preparation, high-speed rotation, and film formation by evaporation. The film thickness can be controlled by controlling the spin coating time, rotation speed, amount dropped, and the concentration and viscosity of the solution used.

[0170] The precursor liquid slit coating method is a coating technique in which a coating liquid is extruded under a constant pressure through a gap in a mold and transferred onto a moving substrate.

[0171] The precursor liquid scraping method is a coating method in which a scraper is used to coat the surface and obtain a thick coating film.

[0172] For example, a method for producing a charge transport layer includes dissolving a charge transport material and a conversion material in a solvent to obtain a charge transport layer slurry, coating the charge transport layer slurry on an upper electrode by a spin coating method, and drying to obtain a charge transport layer of a predetermined thickness.

[0173] In one embodiment, the present application further provides a power consuming device, the power consuming device comprising the solar cell described above.

[0174] The solar cell adopts all the technical solutions of all the above embodiments, and therefore has at least all the beneficial effects of the technical solutions of the above embodiments, and they will not be described one by one here.

[0175] Example

[0176] Example 1

[0177] 1) The surface of a 2.0 cm x 2.0 cm FTO conductive glass was washed twice with acetone and isopropanol, immersed in deionized water and ultrasonically treated for 10 min, dried in a blower oven, and then placed in a glove box (N atmosphere) to be used as the upper electrode.

[0178] 2) Preparation of down-conversion charge (electron) transport layer: A mixed aqueous solution of 1 wt.% tetraethylrhodamine and 3 wt.% SnO2 nanocolloids was spin-coated onto the FTO layer at 4000 rpm to 6500 rpm, and then heated on a constant-temperature hot stage at 150°C for 15 min to a thickness of 40 nm.

[0179] 3) Preparation of perovskite layer (light absorption layer): A 1.5 mol / L solution of FAPbI3 in DMF was spin-coated onto the obtained electron transport layer at a speed of 3000 rpm to 4500 rpm, then transferred to a constant temperature hot stage and heated at 100°C for 30 min. After cooling to room temperature, a 500 nm thick perovskite layer was formed.

[0180] 4) Preparation of the second charge transport layer: A chlorobenzene solution of Spiro-OMeTAD with a concentration of 73 mg / mL was spin-coated onto the perovskite layer at a speed of 3000 rpm to 4000 rpm to a thickness of 150 nm.

[0181] 5) Preparation of Ag electrode (bottom electrode): The above sample was placed in a vacuum coater and 5 × 10 -4 Under vacuum conditions of 0.1 Pa, an Ag electrode was evaporated on the surface of the obtained hole transport layer, the evaporation rate was 0.1 angstroms / s, and the thickness of the Ag electrode was 80 nm.

[0182] In this way, the perovskite solar cell of Example 1 was obtained.

[0183] In Examples 2 to 11, based on Example 1, parameters such as the type and ratio of the down-conversion luminescent material, the up-conversion luminescent material, and the thickness of the charge transport layer were adjusted to obtain Examples 2 to 11.

[0184] In Comparative Example 1, the upper electrode, the perovskite layer, the second charge transport layer, and the lower electrode were fabricated in the same manner as in Example 1.

[0185] Fabrication of the first charge (electron) transport layer: A mixed aqueous solution of 3 wt.% SnO2 nanocolloids was spin-coated onto the FTO layer at 4000 rpm to 6500 rpm, and then heated on a constant-temperature hot stage at 150°C for 15 minutes to a thickness of 40 nm.

[0186] As a result, the perovskite solar cell of Comparative Example 1 was obtained.

[0187] Performance testing of perovskite solar cells

[0188] The performance of the perovskite solar cells of the examples and comparative examples was tested.

[0189] Specifically, the energy conversion efficiency of the perovskite cells of each example and comparative example was measured. In an atmospheric environment, an AM1.5G standard light source was used as a sunlight-simulating light source. The voltage-current characteristic curve of the cell under illumination by the light source was measured using a 4-channel digital source meter (Keithley 2440). The open-circuit voltage Voc, short-circuit current density Jsc, and fill factor FF of the cell were obtained, and the energy conversion efficiency Eff of the cell was calculated based on these. As can be seen, introducing an upconversion luminescent material and / or a downconversion luminescent material into a solar cell is advantageous in increasing the utilization rate of the solar spectrum, increasing the photo-generated current, and further improving the energy conversion efficiency.

[0190] The energy conversion efficiency is calculated as follows: Eff=Pout / Popt

[0191] =Voc×Jsc×(Vmpp×Jmpp) / (Voc×Jsc)

[0192] =Voc×Jsc×FF

[0193] where Pout, Popt, Vmpp, and Jmpp are the operating output power of the battery, the incident light power, the maximum power point voltage, and the maximum power point current of the battery, respectively.

[0194] The results are shown in Table 1.

[0195] [Table 1-1] [Table 1-2]

[0196] Example 12

[0197] 1) The surface of a 2.0 cm x 2.0 cm FTO conductive glass was washed twice with acetone and isopropanol, immersed in deionized water and ultrasonically treated for 10 min, dried in a blower oven, and then placed in a glove box (N atmosphere) to be used as the upper electrode.

[0198] 2) Light conversion layer: A mixed aqueous solution of 1 wt.% tetraethylrhodamine and 1 wt.% NaYF4 was spin-coated on one side of the FTO layer at 4000 rpm to 6500 rpm, and then heated on a constant temperature hot stage at 150°C for 15 minutes to a thickness of 40 nm.

[0199] 3) Preparation of charge (electron) transport layer: A mixed aqueous solution of 3 wt.% SnO2 nanocolloids was spin-coated onto the FTO layer at 4000 rpm to 6500 rpm, and then heated on a constant temperature hot stage at 150°C for 15 minutes to a thickness of 40 nm.

[0200] 4) Preparation of perovskite layer (light absorption layer): A 1.5 mol / L solution of FAPbI3 in DMF was spin-coated onto the obtained electron transport layer at a speed of 3000 rpm to 4500 rpm, then transferred to a constant temperature hot stage and heated at 100°C for 30 min. After cooling to room temperature, a 500 nm thick perovskite layer was formed.

[0201] 5) Preparation of the second charge transport layer: A chlorobenzene solution of Spiro-OMeTAD with a concentration of 73 mg / mL was spin-coated onto the perovskite layer at a speed of 3000 rpm to 4000 rpm to a thickness of 150 nm.

[0202] 6) Preparation of Ag electrode (bottom electrode): The above sample was placed in a vacuum coater and 5 × 10 -4 Under vacuum conditions of 0.1 Pa, an Ag electrode was evaporated on the surface of the obtained hole transport layer, the evaporation rate was 0.1 angstroms / s, and the thickness of the Ag electrode was 80 nm.

[0203] As a result, the perovskite solar cell of Example 12 was obtained.

[0204] In Example 13, based on Example 12, a light conversion layer was provided between the upper electrode and the first charge transport layer.

[0205] In Example 14, based on Example 12, a light conversion layer was provided between the first charge transport layer and the light absorption layer.

[0206] [Table 2]

[0207] In Example 15, based on Example 12, step 2) was not performed, and an up-conversion luminescent material and a down-conversion luminescent material were added to the upper electrode.

[0208] [Table 3]

[0209] As can be seen from Tables 1 to 3, the energy conversion efficiency of a solar cell is improved by introducing an upconversion luminescent material and / or a downconversion luminescent material into the solar cell.

[0210] The above is merely a preferred embodiment of the present application, and does not limit the patent scope of the present application. Any equivalent structural modifications made using the contents of the specification and drawings of the present application based on the idea of ​​the present application, or those directly or indirectly applied to other related technical fields, are all included in the scope of patent protection of the present application.

Claims

1. 1. A light conversion layer to be applied to a solar cell, the light conversion layer comprising a conversion material, the conversion material comprising an up-conversion luminescent material and / or a down-conversion luminescent material, the light conversion layer being provided on a light incident side of a light absorption layer of the solar cell.

2. the solar cell includes an upper electrode, and the light conversion layer is provided on a surface of the upper electrode; and / or the solar cell comprises an upper electrode and a first charge transport layer, and the light conversion layer is provided between the upper electrode and the first charge transport layer; and / or the solar cell comprises a first charge transport layer and a light absorbing layer, and the light conversion layer is provided between the first charge transport layer and the light absorbing layer.

3. The light conversion layer of claim 1 , wherein the solar cell comprises a top electrode, the light conversion layer being the top electrode, and the light conversion layer including a top electrode material and the conversion material.

4. 10. The light conversion layer of claim 1, wherein the solar cell comprises a first charge transport layer, the light conversion layer being a first charge transport layer, the light conversion layer comprising a charge transport material and the conversion material.

5. 5. The light conversion layer of claim 4, wherein the weight of the conversion material accounts for 1% to 75% of the total weight of the materials in the light conversion layer.

6. 6. The light conversion layer of claim 5, wherein the weight of the conversion material accounts for 25% to 60% of the total weight of the material of the light conversion layer.

7. The light conversion layer according to any one of claims 1 to 6, wherein the range of thickness of the light conversion layer is in the range of 30 nm to 60 nm.

8. The light conversion layer of claim 7, wherein the thickness range of the light conversion layer includes 40 nm to 50 nm.

9. the light conversion layer comprises the charge transport material, the up-conversion luminescent material, and the down-conversion luminescent material, and the mass of the up-conversion luminescent material accounts for a range value greater than 0 and less than or equal to 25% of the total mass of materials in the light conversion layer; the mass of the down-conversion luminescent material accounts for a range value of more than 0% to 25% of the total mass of materials of the light conversion layer; 7. The light conversion layer according to claim 4, wherein the mass of the charge transport material accounts for 50% or more and less than 100% of the total mass of materials in the light conversion layer.

10. The light conversion layer according to any one of claims 1 to 6 and 8, wherein the conversion material comprises an up-conversion luminescent material, and the up-conversion luminescent material comprises at least one of an organic compound or an inorganic compound.

11. the organic compound includes at least one of 4CzIPN, thioxanthone, and triphenylamine; and / or the inorganic compound is NaYF ４ , NaLuF ４ , NaGdF ４ , NaYbF ４ , NaYGd, NaYLu, NaYNd, NaGd (WO ４ ) ２ , LiErF, BaYF ５ , BaLuF ５ , BaGdF ５ ,BaYb ２ F, CaS, LiLa(MoO ４ ) ２ , Gd ２ O ３ , ZrYO, YalO ３ , CaWO ４ and the NaYF doped with one or more of Yb, Er, Tm, Eu, Sm, Bi and Ho rare earth elements. ４ , the NaLuF ４ , the NaGdF ４ , the NaYbF ４ , the NaYGd, the NaYLu, the NaYNd, the NaGd(WO ４ ) ２ , the LiErF, the BaYF ５ , the BaLuF ５ , the BaGdF ５ , the BaYb ２ F, the CaS, the LiLa(MoO ４ ) ２ , the Gd ２ O ３ , the ZrYO, the YAlO ３ , the CaWO ４ The light conversion layer of claim 10 comprising at least one of:

12. The light conversion layer according to any one of claims 1 to 6, 8 and 11, wherein the conversion material comprises a down-conversion luminescent material, and the down-conversion luminescent material comprises a fluorescent material and / or a phosphorescent material.

13. the down-conversion luminescent material comprises a fluorescent material, the fluorescent material comprising at least one of riboflavin, a fluorescein-based compound, a rhodamine-based compound, phycoerythrin, an iridium complex, a rare earth element complex, a polyfluorene-based compound, a coumarin-based compound, a naphthalimide-based compound, a polyacene-based compound, a bodipy-based compound, a resorufin-based compound, a pyrazoline-based compound, a triphenylamine-based compound, a carbazole-based compound, a green fluorescent protein, a diamine-based fluorescent compound, a perovskite luminescent nanomaterial, and a thermally activated delayed fluorescent compound; and / or the down-conversion luminescent material comprises a phosphorescent material, the phosphorescent material comprising a matrix, the matrix comprising at least one of sulfides, oxides, selenides, fluorides, phosphates, silicates and tungstates of Group II metals; And / or the down-conversion luminescent material comprises a phosphorescent material, the phosphorescent material comprises a matrix and an activator, and the activator comprises a heavy metal.

14. The light conversion layer according to any one of claims 4 to 6, wherein the charge transport material comprises an electron transport material or a hole transport material.

15. 15. The light conversion layer of claim 14, wherein the electron transport material comprises at least one of an imide-based compound, a quinone-based compound, a fullerene and its derivatives, a metal oxide, a semiconductor material oxide, a titanate, and a fluoride.

16. the imide-based compound includes at least one of phthalimide, succinimide, N-bromosuccinimide, glutarimide, and maleimide; and / or the quinone-based compound includes at least one of benzoquinone, naphthoquinone, phenanthrenequinone, and anthraquinone; And / or the fullerene and its derivatives are C ６０ and PCBM, and / or the metal element in the metal oxide includes at least one of Mg, Cd, Zn, In, Pb, W, Sb, Bi, Hg, Ti, Ag, Mn, Fe, V, Sn, Zr, Sr, Ga, and Cr; and / or the semiconductor material oxide comprises silicon oxide; and / or the titanate comprises at least one of strontium titanate and calcium titanate; and / or the fluoride comprises at least one of lithium fluoride and calcium fluoride.

17. 15. The light conversion layer of claim 14, wherein the hole transport material comprises at least one of 2,2',7,7'-tetra(N,N-di-p-methoxyphenylamino)-9,9'-spirobifluorene, methoxytriphenylamine-fluoroformamidine, poly[bis(4-phenyl)(2,4,6-trimethylphenyl)amine], poly(3,4-ethylenedioxythiophene), polystyrenesulfonic acid, poly(3-hexylthiophene), triptycene-cored triphenylamine, 3,4-ethylenedioxythiophene-methoxytriphenylamine, N-(4-aniline)carbazole-spirobifluorene, polythiophene, a phosphate group monomer, a carbazolyl group monomer, a sulfonic acid group monomer, a triphenylamine group monomer, an aromatic group monomer, a metal oxide, and cuprous thiocyanate, wherein the metal element in the metal oxide comprises at least one of Ni, Mo, and Cu.

18. A solar cell comprising the light conversion layer according to any one of claims 1 to 17.

19. Along a first direction, the solar cell sequentially comprises an upper electrode, a first charge transport layer, a light absorbing layer, a second charge transport layer, and a lower electrode; the first charge transport layer includes the light conversion layer according to any one of claims 1 to 17, and the charge transport material in the first charge transport layer includes one of an electron transport material and a hole transport material; 20. The solar cell of claim 18, wherein the charge transport material in the second charge transport layer comprises the other of an electron transport material and a hole transport material.

20. 20. The solar cell according to claim 19, wherein the material of the upper electrode and / or the lower electrode comprises an organic conductive material and / or an inorganic conductive material.

21. the organic conductive material includes at least one of poly(3,4-ethylenedioxythiophene), polythiophene, and polyacetylene; and / or the inorganic conductive material is fluorine-doped SnO ２ 21. The solar cell of claim 20, comprising at least one of transparent conductive glass, aluminum doped zinc oxide transparent conductive glass, and a metal.

22. 22. The solar cell according to claim 19 or 21, wherein the material of the light absorbing layer comprises a perovskite, and the structural formula of the perovskite is ABX3, where A is an inorganic cation and / or an organic anion, B is an inorganic cation and / or an organic cation, and X is an inorganic anion and / or an organic anion.

23. A power consuming device comprising the solar cell according to any one of claims 18 to 22.

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