Disclosure of Invention
Therefore, it is necessary to provide a solar cell and a preparation method thereof to solve the problems of large light loss, small photovoltaic working area and high internal resistance easily formed in the solar cell in the conventional perovskite thin film solar cell structure.
The application provides a solar cell, including:
a transparent substrate;
the light absorption layer is arranged on the first surface of the transparent substrate and is made of a perovskite structure material;
the electron transport layer and the hole transport layer are arranged on the surface, far away from the transparent substrate, of the light absorption layer;
the positive electrode is arranged on the surface, far away from the light absorption layer, of the hole transport layer; and
and the negative electrode is arranged on the surface of the electron transmission layer, which is far away from the light absorption layer.
According to a specific embodiment of the present application, the electron transport layers and the hole transport layers are alternately disposed.
According to a specific embodiment of the present application, the electron transport layer and the hole transport layer are in contact or not in contact in a thickness direction perpendicular to the light absorbing layer. Optionally, the electron transport layer and the hole transport layer are not in contact in a thickness direction perpendicular to the light absorbing layer. Further, the distance between the electron transport layer and the hole transport layer is 50nm to 300 nm.
According to an embodiment of the present application, the solar cell further comprises:
and the first protective layer is clamped between the hole transport layer and the positive electrode. Optionally, the material of the first protective layer is selected from graphite, graphene, NiOxOr MoOyWherein x is more than 0 and less than 2, and y is more than 0 and less than 3.
According to an embodiment of the present application, the solar cell further comprises:
and the second protective layer is clamped between the electron transmission layer and the negative electrode. Optionally, the material of the second protective layer is selected from SnO2ZnO or TiO2At least one of (1).
According to an embodiment of the present application, the positive electrode and the negative electrode may be a single-layer electrode or a multi-layer electrode, respectively. Optionally, the material of the positive electrode and the negative electrode is an electrode material commonly used in the field of solar cells, such as one or more selected from Al, Mo, Ag, Cr, Ni, Cu, Sn, graphite, and graphene. In other words, when the positive electrode or the negative electrode is a single-layer electrode, the material of the electrode may be one or more of Al, Mo, Ag, Cr, Ni, Cu, Sn, graphite, and graphene; when the positive electrode or the negative electrode is a multilayer electrode, the electrode materials of the layers can be the same or different, and the material of each layer of electrode can be one or more of Al, Mo, Ag, Cr, Ni, Cu, Sn, graphite and graphene.
According to an embodiment of the present application, the solar cell further comprises:
the barrier layer is clamped between the transparent substrate and the light absorption layer; optionally, the material of the barrier layer is selected from silicon oxide, silicon nitride, aluminum oxide or magnesium oxide.
According to an embodiment of the present application, the solar cell further comprises:
an antireflection layer provided on the linerOn a second surface of the sole opposite the first surface. The material of the antireflection layer can be a material with an antireflection function, which is commonly used in the field of solar cells. Optionally, the material of the antireflection layer is selected from materials with refractive indexes of 1 to 1.5, and preferably, the material of the antireflection layer is MgF2。
A method for manufacturing a solar cell includes the following steps:
forming a light absorption layer on a first surface of a transparent substrate, wherein the light absorption layer is made of a perovskite structure material;
forming a hole transport layer on a surface of the light absorbing layer;
forming a positive electrode on the surface of the hole transport layer;
forming an electron transport layer on the surface of the light absorption layer;
and arranging a negative electrode on the surface of the electron transport layer.
According to an embodiment of the present application, the hole transport layers and the electron transport layers are alternately disposed on the surface of the light absorbing layer.
According to a specific embodiment of the present application, the method for manufacturing a solar cell further includes: forming a first protective layer on the hole transport layer, and then forming the positive electrode on the first protective layer; optionally, the material of the first protection layer is graphite, graphene or an inert metal.
According to a specific embodiment of the present application, the method for manufacturing a solar cell further includes: forming a second protective layer on the electron transport layer, and then forming the negative electrode on the second protective layer; optionally, the material of the second protective layer is SnO2ZnO or MoOyWherein y is more than 0 and less than 3.
According to an embodiment of the present application, the positive electrode and the negative electrode may be a single-layer electrode or a multi-layer electrode, respectively. Optionally, the material of the positive electrode and the negative electrode is one or more of Al, Mo, Ag, Cr, Ni, Cu, Sn, graphite, and graphene.
According to an embodiment of the present application, before forming a light absorbing layer on the first surface of the light-transmitting substrate, the light absorbing layer is a material having a perovskite structure, the method further includes:
forming a barrier layer on the first surface of the light-transmitting substrate, and forming the light absorbing layer on the barrier layer.
The solar cell provided herein includes a light-transmitting substrate, a light-absorbing layer, an electron transport layer, a hole transport layer, a positive electrode, and a negative electrode. The electron transport layer and the hole transport layer are both arranged on the surface, far away from the light-transmitting substrate, of the light absorption layer. The light incident surface of the solar cell is not provided with an electron transmission layer and a hole transmission layer in a stacking mode, and the light incident surface of the solar cell is not provided with a transparent front electrode, so that the light energy entering the light absorption layer is greatly increased, and the short-circuit current of the solar cell is increased. The solar cell is not provided with a front electrode any more, so that the area waste when the front electrode is led out can be avoided, and the full-area conversion efficiency of the solar cell is increased.
Detailed Description
In order to make the objects, technical solutions and advantages of the present application more apparent, the present application is described in further detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present application and are not intended to limit the present application.
Referring to fig. 1, a solar cell 100 according to an embodiment of the present disclosure includes a light-transmitting substrate 10, a light-absorbing layer 30, an electron transport layer 40, a hole transport layer 50, a positive electrode 60, and a negative electrode 70.
According to an embodiment of the present invention, the perovskite material may generally be of the formula ABX3Generally, the configuration of (a) is a cubic or octahedral structure. The A ion is positioned in the center of the cubic unit cell, and is surrounded by 12X ions to form a coordination cubic octahedron, and the coordination number is 12; the B ion is located at the vertex of the cubic unit cell, and is surrounded by 6X ions to form a coordination octahedron with coordination number of 6. Wherein, the radii of the A ions and the X ions are close to each other, and the A ions and the X ions form cubic close packing together. The a ions in the perovskite material are generally referred to as organic cations, most commonly CH3NH3 +(RA ═ 0.18nm), others such as NH2CH=NH2 +(RA=0.23nm),CH3CH2NH3 +(RA ═ 0.19-0.22nm) has also found certain applications. The B ion refers to a metal cation, mainly containing Pb2+(RB ═ 0.119nm) and Sn2+(RB ═ 0.110 nm). The X ion being a halide anion, i.e. I-(RX=0.220nm)、Cl-(RX ═ 0.181nm) and Br-(RX=0.196nm)。
The material of the transparent substrate 10 may be transparent, and may be, for example, glass or a light-permeable (including transparent) polymer plate. The light-transmitting substrate 10 may be glass or soda-lime glass, for example. The choice of the transparent substrate 10 can be continuously updated according to the development of technology.
According to a specific embodiment of the present application, a barrier layer 20 is deposited on the first surface of the transparent substrate 10. The barrier layer 20 mainly functions to block diffusion of atoms in the light-transmitting substrate 10 to other layers. The material used for the barrier layer 20 may be a barrier layer material commonly used in the art, and for example, may be one or more of silicon oxide, silicon nitride, aluminum oxide, or magnesium oxide, where the proportion of oxygen or nitrogen in the oxide or nitride may be adjusted as needed. The barrier layer 20 may have a thickness of 2 nanometers to 2000 microns. Preferably, the barrier layer 20 has a thickness of 10nm to 100 nm. According to a specific embodiment of the present application, an antireflection layer 101 is formed on the second surface of the transparent substrate 10. The antireflection layer 101 serves to increase the light absorption intensity. The material of the antireflection layer 101 may be an antireflection layer material commonly used in the art. Optionally, the material of the anti-reflection layer 101 is selected from materials with a refractive index of 1 to 1.5. Preferably, the material of the anti-reflection layer 101 may be MgF2A material. According to another embodiment of the present application, the second surface of the transparent substrate 10 may be textured for reducing reflection and increasing light absorption intensity. In this embodiment, the blocking layer 20 can prevent diffusion of metal into the charge transport layer; it is also possible to prevent damage to the electron transport layer 40 or the hole transport layer 50 when an electrode is deposited.
The light absorption layer 30 is disposed on the first surface of the light transmissive substrate 10 or on the surface of the barrier layer 20. The material used for the light absorbing layer 30 may be any material commonly used in the art, for example, the material of the light absorbing layer 30 is perovskite structure. The material of the light absorbing layer 30 may be (FAPbI)3)x(MAPbBr3)1-xWherein x is more than 0 and less than 1. Wherein, the chemical structural formula of FA is CH (NH)2)2 +The chemical structural formula of MA is CH (NH)2)2 +. The light absorbing layer 30 may have a thickness of 100nm to 2000 nm. Preferably, the light absorbing layer 30 has a thickness of 250nm to 500 nm. The thickness of the light absorbing layer 30 is different, which also affects the photoelectric conversion efficiency of the solar cell 100.
The electron transport layer 40 is disposed on the surface of the light absorption layer 30 away from the light transmissive substrate 10. The electron transport layer 40 may be made of an electron transport layer material commonly used in the art. For example, materials for the electron transport layer 40 include, but are not limited to, SnO2And ZnO. The material of the electron transport layer 40 may also be a composite structure formed by multiple layers of materials. The width of the electron transport layer 40 is 50nm to 20 mm. Preferably, the width of the electron transport layer 40 is 300nm to 100 μm. The thickness of the electron transport layer 40 is 1nm to 10 μm. The electron transport layer 40 preferably has a thickness of 5 nm to 100 nm.
The hole transport layer 50 is disposed on the surface of the light absorbing layer 30 away from the light transmissive substrate 10. The material that can be used for the hole transport layer 50 may be a hole transport layer material commonly used in the art. The hole transport layer 50 includes, but is not limited to, PTAA and CuSCN. The hole transport layer 50 may have a single-layer structure or a multi-layer structure. The width of the hole transport layer 50 is 50nm to 20 mm. Preferably, the width of the hole transport layer 50 is 300nm to 100 μm. The hole transport layer 50 has a thickness of 1nm to 10 μm. Preferably, the hole transport layer 50 may have a thickness of 5 nm to 100 nm.
The main function of the electron transport layer 40 and the hole transport layer 50 is to extract electrons or holes from the light absorbing layer 30, and to prevent electron-hole pairs from recombining at the interface of the light absorbing layer 30 or each film layer. Therefore, other materials and configurations are suitable for this purpose. The electron transport layer 40 and the hole transport layer 50 may be disposed on a surface of the light absorbing layer 30 away from the light transmissive substrate 10. The electron transport layer 40 and the hole transport layer 50 may be in the form of stripes, ribbons, or other shapes as designed by those skilled in the art. In addition, the hole transport layer 50 is spaced apart from the electron transport layer 40 by a first distance. According to a specific embodiment of the present application, the first pitch may be 0nm to 10 mm. The first interval between the electron transport layer 40 and the hole transport layer 50 may be 0, that is, the electron transport layer 40 and the hole transport layer 50 may be in close contact. The first spacing between the electron transport layer 40 and the hole transport layer 50 may also be any distance between 0 nanometers and 10 millimeters. Such as a first spacing of 100nm between the electron transport layer 40 and the hole transport layer 50.
The positive electrode 60 is disposed on the surface of the hole transport layer 50 away from the light absorbing layer 30. The cathode 70 is disposed on the surface of the electron transport layer 40 away from the light absorbing layer 30. The positive electrode 60 and the negative electrode 70 are disposed at a second interval. The first pitch and the second pitch may be equal or unequal. The second pitch needs to be greater than zero. For example, when the first spacing distance is 1 micrometer, the second spacing distance may also be 0.5 micrometer.
According to a specific embodiment of the present application, the material of the positive electrode 60 and the negative electrode 70 is a metal material, a conductive material, or a composite material including a metal material and a conductive material. For example, the positive electrode 60 and the negative electrode 70 may have a single-layer electrode structure or a composite structure of multiple layers of electrodes. When the anode or the cathode is a single-layer electrode, the material of the electrode is one or more of Al, Mo, Ag, Cr, Ni, Cu, Sn, graphite and graphene; when the positive electrode or the negative electrode is a multilayer electrode, the electrode materials of the layers can be the same or different, and the material of each layer of electrode can be a metal material such as Al, Mo, Ag and the like, can also be other materials with good conductivity such as graphite, graphene and the like, and can also be a composite of various materials. In other words, for example, the positive electrode 60 and the negative electrode 70 may have a multi-layered electrode structure in which three Mo/Al/Cr layers of metal are sequentially stacked on a charge transport material, or a multi-layered electrode structure in which four graphene/Mo/Ag/Cr layers of thin films are sequentially stacked on a charge transport material. The main functions of the positive electrode 60 and the negative electrode 70 are to collect charges conducted from the charge transport layer (including the electron transport layer 40 and the hole transport layer 50) and generate current, while not damaging other materials in the manufacture and operation of the solar cell device. Therefore, other materials and configurations are suitable for this purpose. The positive electrode 60 and the negative electrode 70 may be made of the same material or different materials and structures.
The width of the positive electrode 60 or the negative electrode 70 is 50nm to 20 mm. Preferably, the width of the positive electrode 60 or the negative electrode 70 is 300nm to 100 μm. The total thickness of the positive electrode 60 or the negative electrode 70 is 1nm to 10 μm. Preferably, the total thickness of the positive electrode 60 and the negative electrode 70 is 50nm to 100 nm. The second pitch may be 1 nanometer to 10 millimeters. It is obvious to the person skilled in the art that: in the present application, the distance between the positive electrode 60 and the negative electrode 70 must be greater than 0, so as to avoid direct contact between the positive electrode 60 and the negative electrode 70.
The working principle of the solar cell 100 in this embodiment is as follows: sunlight transmitted through the translucent substrate 10 will also strike the surface of the light absorbing layer 30 through the barrier layer in a specific embodiment, and be absorbed by the light absorbing layer 30. The light absorbing layer 30 absorbs sunlight and then excites electrons of the light absorbing layer 30 to generate electron-hole pairs. The electron-hole pairs are diffused in the light absorbing layer 30, and when electrons are diffused in the electron transport layer 40, the electrons are extracted by the electron transport layer 40 and conducted to the negative electrode 70. When holes diffuse into the hole transport layer 50, the holes are extracted by the hole transport layer 50 and conducted to the positive electrode 60. When a load is applied to the positive electrode 60 and the negative electrode 70, a current flow from the positive electrode 60 to the negative electrode 70 is established.
In this embodiment, the electron transport layer 40, the hole transport layer 50, the positive electrode 60, and the negative electrode 70 are integrated on the back surface of the solar cell 100, which is provided with the solar cell 100. The electron transport layer 40 and the hole transport layer 50 disposed on the backlight surface of the solar cell 100 absorb sunlight to generate electron-hole pairs (excitons), when the electron-hole pairs diffuse to the back surface of the light absorbing layer 30, electrons are collected by the electron transport layer 40, and holes are collected by the hole transport layer 50, so that current is collected through the negative electrode 70 and the positive electrode 60, respectively, to generate electric energy.
In this embodiment, the electron transport layer 40 and the hole transport layer 50 are both disposed on the surface of the light absorbing layer 30 away from the light transmissive substrate 10. The electron transport layer 40 and the hole transport layer 50 are not disposed on the light incident surface of the solar cell 100, and the transparent front electrode is not disposed on the light incident surface of the solar cell 100, so that the light energy entering the light absorbing layer 30 is greatly increased, and the short-circuit current of the solar cell 100 is increased. The solar cell 100 is not provided with a front electrode, so that the area waste when the front electrode is led out can be avoided, and the full-area conversion efficiency of the solar cell is increased. The positive electrode 60 and the negative electrode 70 are both disposed on the backlight surface of the solar cell 100, and do not need to transmit light. Therefore, the selection range of the materials of the positive electrode 60 and the negative electrode 70 is wider. The positive electrode 60 and the negative electrode 70 can adopt a metal material with better conductivity to replace a transparent conductive oxide material, so that the internal resistance of the battery is reduced, and the filling factor is improved.
According to one embodiment of the present application, the first pitch (d 1 in FIG. 1) is 0nm to 1 × 107And (5) nm. Optionally, the first pitch is 10nm-1 μm. Preferably, the first pitch is 30nm, 50nm, 80nm, 100nm, 200nm, 300nm or 500 nm. The distance between the electron transport layer 40 and the hole transport layer 50 may be related to the size of the light-transmitting substrate 10 and the ratio of disposing the solar cell. According to an embodiment of the present disclosure, the distance between the electron transport layer 40 and the hole transport layer 50 is 50nm to 300nm, which can reduce the complexity of the manufacturing process and reduce the cost. An appropriate spacing between the electron transport layer 40 and the hole transport layer 50 is provided so that the charge transport capability can be kept to a maximum.
According to an embodiment of the present application, the second pitch (d 2 in fig. 1) may be greater than the first pitch. The second pitch may be smaller than the first pitch as long as direct contact is not made between the positive electrode 60 and the negative electrode 70. In this embodiment, the interval between the electron transport layer 40 and the hole transport layer 50 is the first distance. The spacing within the positive electrode 60 and the negative electrode 70 is a second pitch. In this embodiment, the positive electrode 60 and the negative electrode 70 need to be distinguished from each other, so as to avoid electrical connection between the positive electrode 60 and the negative electrode 70, and enable the solar cell 100 to accurately derive the electrical energy converted by the light absorbing layer 30 and the charge transport layer.
Referring to fig. 2, according to an embodiment of the present application, the solar cell 100 further includes a first protection layer 51. The first protective layer 51 is disposed on the surface of the hole transport layer 50 away from the light absorbing layer 30. The first protective layer 51 is in contact with the positive electrode 60 away from the surface of the hole transport layer 50. The thickness of the first protective layer 51 is not particularly limited. The first protective layer 51 is sandwiched between the hole transport layer 50 and the positive electrode 60. Optionally, the material of the first protective layer 51 is selected from graphite, graphene, NiOxOr MoOyWherein x is more than 0 and less than 2, and y is more than 0 and less than 3. The first protective layer 51 can effectively prevent damage to the hole transport layer 50 during the process. The first protective layer 51 may also be of other materials. The thickness of the first protective layer 51 may be set in combination with the thickness of the hole transport layer 50.
In this embodiment, the hole transport layer 50, the first protective layer 51, and the positive electrode 60 may be deposited by using a mask plate with one configuration, and after the deposition is completed, the hole transport layer, the first protective layer 51, and the positive electrode 60 are removed. And another configuration of mask plate is selected to deposit the electron transport layer 40 and the cathode 70, and after the deposition is finished, the electron transport layer and the cathode are removed. Of course, the hole transport layer 50, the first protective layer 51 and the positive electrode 60 may be deposited in other manners.
According to an embodiment of the present application, the positive electrode 60 includes a first positive electrode 61 and a second positive electrode 62. The first positive electrode 61 is disposed to overlap the second positive electrode 62, and the first positive electrode 61 is interposed between the second positive electrode 62 and the first protective layer 51. The first positive electrode 61 is disposed on a surface of the first protective layer 51 away from the hole transport layer 50. The second positive electrode 62 is disposed on a surface of the first positive electrode 61 away from the first protective layer 51.
In this embodiment, the material of the first positive electrode 61 and the second positive electrode 62 may be metallic aluminum, metallic nickel, or other metallic materials that can be realized by those skilled in the art. In this embodiment, the positive electrode 60 has a laminated structure, which can improve the electrical conduction efficiency of the solar cell 100.
Referring to fig. 3, according to an embodiment of the present disclosure, the solar cell 100 further includes a second protection layer 52 sandwiched between the electron transport layer 40 and the negative electrode 70.
The second protective layer 52 is disposed between the electron transport layer 40 and the negative electrode 70. According to an embodiment of the present application, optionally, the material of the second protective layer 52 is selected from SnO2ZnO or TiO2One or more of (a). The second protective layer 52 can effectively prevent damage to the electron transport layer 40 during the manufacturing process.
If the material of the electron transport layer 40 is SnO2And the metal oxides have good compactness, can stand damage caused by the preparation of the electrode material, and can be provided with no protective layer. If the electron transport layer 40 is C60 or some organic material, the second protective layer 52 needs to be provided. The material of the second protective layer 52 is SnO2ZnO or TiO2One or more of (a).
Referring to fig. 4, a solar cell 100 is provided according to an embodiment of the present application. The solar cell 100 may be a structure in which a plurality of the solar cells 100 are arranged together. The solar cell 100 may be provided with one or a plurality of electricity extraction points. The solar cell 100 includes a light-transmitting substrate 10, a light-absorbing layer 30, a plurality of electron transport layers 40, a plurality of hole transport layers 50, a plurality of positive electrodes 60, and a plurality of negative electrodes 70. Specifically, the selection, thickness and width of each of the above structural materials may be the same as those of the above solar cell 100.
The material of the transparent substrate 10 may be selected the same as that of the solar cell 100. In this embodiment, the size of the translucent substrate 10 may be larger. The light absorbing layer 30 is disposed on the surface of the light transmissive substrate 10. The electron transport layers 40 are disposed at intervals on the surface of the light absorption layer 30 away from the light transmissive substrate 10. Each hole transport layer 50 of the plurality of hole transport layers 50 is disposed between two adjacent electron transport layers 40, and each hole transport layer 50 is disposed on the light absorption layer 30 at a first interval from two adjacent electron transport layers 40. Each of the plurality of positive electrodes 60 is disposed on a surface of one of the hole transport layers 50 remote from the light absorbing layer 30. Each of the plurality of negative electrodes 70 is disposed on a surface of one of the electron transport layers 40 away from the light absorbing layer 30. According to an embodiment of the present disclosure, the plurality of electron transport layers 40 and the plurality of hole transport layers 50 may be alternately arranged on the light absorbing layer 30 as shown in fig. 4 to 6.
In this embodiment, the solar cell 100 integrates the plurality of electron transport layers 40, the plurality of hole transport layers 50, the plurality of positive electrodes 60, and the plurality of negative electrodes 70 in a backlight surface of the solar cell 100. The plurality of electron transport layers 40 and the plurality of hole transport layers 50 disposed on the backlight surface of the solar cell 100 absorb sunlight to generate electron-hole pairs (excitons), when the electron-hole pairs diffuse to the back surface of the light absorbing layer 30, electrons are collected by the plurality of electron transport layers 40, and holes are collected by the plurality of hole transport layers 50, so that current is collected through the plurality of cathodes 70 and the plurality of anodes 60, respectively, to generate electric energy.
In this embodiment, the charge transport layer is not disposed on the light incident surface of the solar cell 100, and the transparent front electrode is not disposed on the light incident surface of the solar cell 100, so that the light energy entering the light absorbing layer 30 is greatly increased, and the short-circuit current of the solar cell 100 is increased. The charge transport layer includes an electron transport layer or a hole transport layer. The solar cell 100 is not provided with a front electrode, so that the area waste when the front electrode is led out can be avoided, and the full-area conversion efficiency of the solar cell is increased. The plurality of anodes 60 and the plurality of cathodes 70 are disposed on a backlight surface of the solar cell 100, and do not need to transmit light. Therefore, the plurality of positive electrodes 60 and the plurality of negative electrodes 70 are more widely selected in material. The positive electrodes 60 and the negative electrodes 70 may be made of a metal material having better conductivity instead of a transparent conductive oxide material, so as to reduce the internal resistance of the battery and improve the fill factor.
According to one embodiment of the present application, the first pitch (d 1 in fig. 4) is 0nm to 1 × 107And (5) nm. In this embodiment, the first distance is set to be suitable for the function of guiding out electrons and/or holes between the plurality of hole transport layers 50 and the plurality of electron transport layers 40. By setting the first distance appropriately, irregular movement of electrons and/or holes in the charge transport layer can be avoided, and the overall transport efficiency of the solar cell 100 can be improved. In this embodiment, the setting of the first pitch may also be selected in combination with the current process conditions.
According to an embodiment of the present application, the second pitch (d 2 in fig. 4) may be greater than the first pitch. The second pitch may also be smaller than the first pitch. The first pitch may be zero, i.e., the plurality of electron transport layers 40 and the plurality of hole transport layers 50 may be in direct contact. The second pitch may not be zero, i.e., the plurality of positive electrodes 60 and the plurality of negative electrodes 70 may not be in direct contact. The plurality of positive electrodes 60 and the plurality of negative electrodes 70 need to be disposed at intervals to avoid electrical connection between the plurality of positive electrodes 60 and the plurality of negative electrodes 70, so that the solar cell 100 can accurately lead out the electrical energy converted by the light absorption layer 30 and the charge transport layer.
Referring to fig. 5, according to an embodiment of the present application, the solar cell 100 further includes a plurality of first protection layers 51. Each first protective layer 51 is disposed on a surface of one of the hole transport layers 50 away from the light absorbing layer 30, and a surface of each first protective layer 51 away from the hole transport layer 50 is in contact with one of the anodes 60.
Referring to fig. 6, according to an embodiment of the present disclosure, the solar cell 100 further includes a plurality of second passivation layers 52. Each of the second passivation layers 52 is disposed on a surface of one of the hole transport layers 50 away from the light absorbing layer 30, and each of the second passivation layers 52 is in contact with one of the anodes 60 on the surface of the hole transport layer 50 away from the light absorbing layer.
In this embodiment, the material selection of each structure of the solar cell 100 provided may be the same as the material selection in the solar cell 100, and is not repeated herein.
According to an embodiment of the present application, the second spacing d2 may also be smaller than the first spacing d1 (shown in fig. 7) as long as no direct contact is made between the positive electrode 60 and the negative electrode 70.
According to an embodiment of the present application, there is provided a method for manufacturing a solar cell panel, including the steps of:
forming a light absorbing layer 30 on a first surface of a transparent substrate 10, the light absorbing layer 30 being a material of perovskite structure;
forming a hole transport layer 50 on a surface of the light absorbing layer 30;
forming a positive electrode 60 on a surface of the hole transport layer 50;
forming an electron transport layer 40 on a surface of the light absorbing layer 30;
a negative electrode 70 is provided on the surface of the electron transport layer 40.
The preparation method of the solar cell panel can be any combination of the above steps in different sequences. For example, the solar cell panel may be manufactured by first manufacturing the electron transport layer 40 and the negative electrode 70, and then manufacturing the hole transport layer 50 and the positive electrode 60. The preparation method of the solar cell panel may also be to prepare the hole transport layer 50 and the anode 60, and then prepare the electron transport layer 40 and the cathode 70. The preparation method of the solar cell panel may further include preparing the electron transport layer 40, preparing the hole transport layer 50, and preparing the anode 60 and the cathode 70 at the same time.
In this embodiment, in the method for manufacturing the solar cell panel, the electron transport layer 40 and the hole transport layer 50 are both disposed on the surface of the light absorption layer 30 away from the transparent substrate 10. The electron transport layer 40 and the hole transport layer 50 are not disposed on the light incident surface of the solar cell 100, and the transparent front electrode is not disposed on the light incident surface of the solar cell 100, so that the light energy entering the light absorbing layer 30 is greatly increased, and the short-circuit current of the solar cell 100 is increased. The solar cell 100 is not provided with a front electrode, so that the area waste when the front electrode is led out can be avoided, and the full-area conversion efficiency of the solar cell is increased. The positive electrode 60 and the negative electrode 70 are both disposed on the backlight surface of the solar cell 100, and do not need to transmit light. Therefore, the selection range of the materials of the positive electrode 60 and the negative electrode 70 is wider. The positive electrode 60 and the negative electrode 70 can adopt a metal material with better conductivity to replace a transparent conductive oxide material, so that the internal resistance of the battery is reduced, and the filling factor is improved.
According to an embodiment of the present invention, the hole transport layers 50 and the electron transport layers 40 are alternately disposed on the surface of the light absorbing layer 30.
In this embodiment, the hole transport layer 50 and the electron transport layer 40 may be disposed on the first surface of the large-sized light-transmitting substrate 10. The hole transport layers 50 and the electron transport layers 40 are alternately arranged, which means that the hole transport layers 50 and the electron transport layers 40 are alternately arranged in one direction in the plane of the light absorbing layer 30, as shown in fig. 4 to 6.
According to an embodiment of the present invention, depositing the electron transport layer 40 on the surface of the light absorption layer 30 may include
S210, providing a first mask plate, and placing the first mask plate on the surface, away from the light-transmitting substrate 10, of the light absorption layer 30.
S220, providing a deposition material of an electron transport layer, and depositing the electron transport layer 40 on the surface of the first mask, where the first mask has a plurality of non-blocked portions, and the deposition material of the electron transport layer directly deposits on the surface of the light absorption layer 30 through the plurality of non-blocked portions of the first mask.
Depositing a cathode 70 on the surface of each electron transport layer 40 away from the light absorbing layer 30 may include
S310, providing a negative electrode material, and further depositing a plurality of negative electrodes 70 after the step S220, wherein the plurality of negative electrodes 70 are directly deposited on the surface of the electron transport layer 40 away from the light absorption layer 30.
In this embodiment, a first mask is provided to realize the electron transport layers 40 and the cathodes 70. Specifically, the parameter of the first mask may be set by a person skilled in the art. The non-blocked portion of the first mask may allow the plurality of electron transport layers 40 to be directly deposited on the surface of the light absorbing layer 30.
According to an embodiment of the present application, a plurality of hole transport layers 50 are deposited on the surface of the light absorption layer 30, and each hole transport layer 50 is disposed between two adjacent electron transport layers 40, including
S410, providing a second mask plate, and placing the second mask plate on the surface, away from the light-transmitting substrate 10, of the light absorption layer 30.
S420, providing a deposition material of a hole transport layer, and depositing a plurality of hole transport layers 50 on the surface of the light absorbing layer 30, where the second mask has a plurality of non-blocked portions, and the deposition material of the hole transport layer is directly deposited on the surface of the light absorbing layer 30 through the plurality of non-blocked portions of the second mask.
S510, providing a positive electrode material, and further depositing a plurality of positive electrodes 60 after the step S420, wherein a plurality of negative electrodes 70 are directly deposited on the surface of the hole transport layer 50 away from the light absorbing layer 30.
In this embodiment, a second mask is provided to implement the plurality of hole transport layers 50 and the plurality of anodes 60. Specifically, the parameters of the second mask may be set by a person skilled in the art. The non-blocked portion of the second mask may allow the plurality of hole transport layers 50 to be directly deposited on the surface of the light absorbing layer 30. According to a specific embodiment of the application, the area of each shielding portion of the first mask plate is larger than the area of each non-shielding portion of the second mask plate. The first and/or second pitch may be determined by the structural arrangement of the first and second masks and the position at which they are placed prior to deposition. In addition, if the first and second pitches are not equal, a third mask and/or a fourth mask may be used to deposit the plurality of anodes 60 and the plurality of cathodes 70.
According to an embodiment of the present application, the method further comprises forming a first protective layer 51 on the hole transport layer 50, and then forming the positive electrode 60 on the first protective layer 51. Optionally, the material of the first protective layer 51 may be selected from graphite, graphene, NiOxOr MoOyWherein x is more than 0 and less than 2, and y is more than 0 and less than 3. The first protective layer 51 can effectively prevent damage to the hole transport layer 50 during the process.
According to an embodiment of the present application, the method further includes forming a second protective layer 52 on the electron transport layer 40, and then forming the negative electrode 70 on the second protective layer 52. The material of the second protective layer 52 is selected from SnO2ZnO or TiO2. The second protective layer 52 can effectively prevent damage to the electron transport layer 40 during the manufacturing process.
According to a specific embodiment of the present application, the positive electrode 60 and the negative electrode 70 may be a single-layer electrode or a multi-layer electrode, respectively, and optionally, the material of the positive electrode 60 and the negative electrode 70 is at least one of Al, Mo, Ag, Cr, Ni, Cu, Sn, graphite, or graphene, i.e., one or more.
According to an embodiment of the present application, before forming the light absorbing layer 30 on the first surface of the light transmissive substrate 10, the forming the light absorbing layer 30 is a material having a perovskite structure, forming a barrier layer 20 on the first surface of the light transmissive substrate 10, and forming the light absorbing layer 30 on the barrier layer 20. The barrier layer 20 mainly functions to block diffusion of atoms in the light-transmitting substrate 10 to other layers. The material used for the barrier layer 20 may be one or more of silicon oxide, silicon nitride, aluminum oxide, or magnesium oxide, wherein the proportion of oxygen or nitrogen in the oxide or nitride may be adjusted as required.
Based on the present application, the following specific examples are provided:
Example three:
firstly, glass is selected as the transparent substrate 10, and SiO is deposited on the surface of the glass transparent substrate by adopting a PECVD (plasma enhanced chemical vapor deposition) methodx(silicon oxide) as the barrier layer 20.
And (II) depositing the light absorption layer 30 on the transparent substrate on which the silicon nitride is deposited. The light absorbing layer 30 is made of FA0.15MA0.85PbI3(ii) a The thickness was 500 nm. The deposition method is co-evaporation, and the evaporation source has PbI2、MAI、FAI,PbI2The source temperature is 350 ℃, the MAI source temperature is 150 ℃, and the FAI source temperature is 100 ℃; the temperature of the transparent substrate is 50 ℃; the vacuum chamber pressure was 0.1 pa.
(iii) forming the hole transport layer 50 and the positive electrode 60 on the light absorbing layer 30. In order to form a grid line structure between the hole transport layer 50 and the anode 60, a second mask plate covers the light absorption layer 30, and covers the area where the hole transport layer 50 does not need to be plated, the area of the slits with hollowed-out masks is 10 microns, and the gap between the slits is 12 microns. PTAA with a thickness of 10nm is prepared as the hole transport layer 50 by a spray coating method, and then baked and sintered.
(IV) deposition of 20nm thick MoO by PECVD methodxA layer (where the range may be 0-3), a 500nm thick metallic Mo film was deposited by magnetron sputtering as the positive electrode 60. Wherein MoOxThe layer may prevent magnetron sputtering from damaging the hole transport layer 50. Removing the second mask plate after the film coating is finished to form the hole transport layer 50 and MoOxA grid line structure in which layers and the anode 60 are stacked together. Width of the resulting gate line structure10 microns in thickness and 530nm in total thickness.
And (V) after the gate line structures of the hole transport layer 50 and the anode 60 are deposited, covering the first mask plate again, wherein the slit area of the hollowed mask is 10 microns, and the gap between the slits is 12 microns. The central line of the slit region of the mask coincides with the central line of the hollow-out region of the gate line structure of the hole transport layer 50 and the anode 60. Then 50nm thick SnO was deposited by ALD2As the electron transport layer 40, Mo with a thickness of 500nm is deposited by magnetron sputtering as the negative electrode 70. And after the film coating is finished, taking down the first mask plate to form a grid line structure of the electron transmission layer 40 and the cathode 70.
In this embodiment, one solar cell 100 may be manufactured after the above processes are completed. The solar cell 100 may be formed if a plurality of the solar cells 100 are connected in series and in parallel. The interconnection can be achieved by connecting the negative electrode 70 and the positive electrode 60 of each solar cell 100 in series and parallel. According to an embodiment of the present application, the large-sized transparent substrate 10 can be directly selected to directly prepare the solar cells 100 in series and parallel. The solar cell 100 is subjected to an encapsulation process to produce more solar cell devices.
Referring to table 1, the solar cell 100 prepared in the three embodiments of the present application is compared with the conventional cell test parameters. The conventional cell in table 1 is a structure in which a light-transmitting substrate, a barrier layer, a transparent conductive oxide layer (negative electrode), an electron transport layer, a light absorbing layer, a hole transport layer, and a positive electrode are sequentially stacked as a comparative example. The important points to be explained are: the electron transport layer, the light absorbing layer and the hole transport layer are stacked, and the electron transport layer and the hole transport layer are not disposed on the same surface of the light absorbing layer. In the conventional battery as a comparative example, the material used for each film layer was the same as that used in example one of the present application. The barrier layer of a conventional cell has a thickness of 20 nm. The thickness of the transparent conductive oxide layer (negative electrode) of the conventional cell was 400 nm. The thickness of the electron transport layer of a conventional battery is 50 nm. The light absorbing layer of the conventional cell has a thickness of 400 nm. The hole transport layer of a conventional cell has a thickness of 100 nm. The thickness of the positive electrode of the conventional battery is 260 nm. It can be seen in table 1 that the various properties of the solar cell 100 prepared in the present application are superior to conventional cell structures to varying degrees.
Table 1: test parameter comparison table of solar cell 100 and traditional cell
The conventional cell, the solar cell of example one, the solar cell of example two and the solar cell of example three in table 1 were all carried out using IEC60904-3:2008 standard. Wherein the total area of the solar cell 100 refers to the total area of the cell as measured by front projection or reflection. A higher total area efficiency of the solar cell 100 indicates a higher utilization of sunlight by the solar cell 100. The effective area efficiency may be the area of the solar cell 100 that can generate electricity. The higher the effective area efficiency of the solar cell 100, the greater the power generation capability of the functional layers of the solar cell 100. According to the specific embodiment of the present application, the total area efficiency of the obtained solar cell 100 is between 17% and 20%, which is much greater than that of the conventional cell. According to the specific embodiment of the present application, the effective area efficiency of the solar cell 100 is between 19% and 22%, which is greater than that of the conventional cell.
The open circuit voltage of the solar cell 100 is an electromotive force generated between the positive electrode and the negative electrode of the solar cell 100 due to light irradiation. When the external circuit is switched on, the current can be continuously output as long as the illumination is not stopped. The open circuit voltage of the solar cell 100 may be obtained by a test method in the art, such as voltmeter measurement or potential compensation measurement. The higher the open circuit voltage of the solar cell 100 is, the stronger the electromotive force generated between the positive electrode and the negative electrode of the solar cell 100 is. In one embodiment of the present application, the open circuit voltage of the solar cell 100 can be up to 1.14V.
The current density is the short circuit current of the solar cell 100 divided by the area of the cell absorber layer that is illuminated. The current density of the solar cell 100 flows in a direction from the positive electrode 60 to the negative electrode 70. When the open-circuit voltage and the fill factor of the solar cell 100 are not reduced, the larger the current density obtained by the test is, the better the performance of the solar cell 100 is. In the present embodiment, the current density of the solar cell 100 is 23mA/cm2-24mA/cm2And much higher than the current density of conventional batteries.
The Fill Factor (FF) refers to a ratio of a product of a current and a voltage at which the solar cell 100 has a maximum output power to a product of a short circuit current and an open circuit voltage. The fill factor should be as close to 1 (i.e., 100%) as possible, with the greater the fill factor, the higher the quality of the solar cell 100. In embodiments of the present application, the fill factor of the solar cell 100 is between 79% and 85%. The fill factor can vary depending on the material and device structure of the solar cell 100.
The technical features of the embodiments described above may be arbitrarily combined, and for the sake of brevity, all possible combinations of the technical features in the embodiments described above are not described, but should be considered as being within the scope of the present specification as long as there is no contradiction between the combinations of the technical features.
The above-mentioned embodiments only express several embodiments of the present application, and the description thereof is more specific and detailed, but not construed as limiting the scope of the invention. It should be noted that, for a person skilled in the art, several variations and modifications can be made without departing from the concept of the present application, which falls within the scope of protection of the present application. Therefore, the protection scope of the present patent shall be subject to the appended claims.