Annealing device, annealing method and perovskite layer preparation method

Abstract

The invention discloses an annealing device, an annealing method and a perovskite layer preparation method, the annealing device is used for heating and crystallizing a perovskite layer, and the annealing device comprises a radiation light source and a bearing table; the radiation light source is used for generating radiation light, and the radiation light is used for heating the perovskite layer; the bearing platform is arranged opposite to the radiation light source and is used for supporting a substrate attached with a perovskite layer; the side, facing the radiation light source, of the bearing table is provided with a rough layer, and the rough layer is located on the side, back to the radiation light source, of the perovskite layer, receives radiation light penetrating through the perovskite layer and scatters at least part of the radiation light to the perovskite layer. The annealing device, the annealing method and the perovskite layer preparation method are used for improving the crystallization quality of the perovskite layer after annealing.

Description

Technical Field

[0001] The present invention relates to the technical field of annealing devices, and in particular to an annealing device, an annealing method and a perovskite layer preparation method. Background Art

[0002] The perovskite layer is the core structural layer that determines the photoelectric conversion efficiency of perovskite solar cells. When preparing the perovskite layer, a perovskite precursor liquid is generally coated on a glass substrate to form a liquid perovskite layer, and then the liquid perovskite layer is subjected to steps such as desolventizing, drying, annealing and crystallization to obtain the desired perovskite layer.

[0003] The existing method for annealing the perovskite layer is generally thermal conduction annealing. In the thermal conduction annealing method, a glass substrate coated with a perovskite layer is generally placed on a hot plate, and then the hot plate generates heat and conducts it to the perovskite layer through the glass substrate to anneal the perovskite layer. This method requires the hot plate to be heated to a relatively high temperature. The glass substrate may bend and deform under the heating of the hot plate, resulting in uneven contact between the glass substrate and the hot plate, which in turn leads to uneven distribution of heat conducted from the hot plate to the perovskite layer, affecting the annealing crystallization quality of the perovskite layer. Summary of the invention

[0004] The object of the present invention is to provide an annealing device, an annealing method and a perovskite layer preparation method, which are used to improve the crystallization quality of the perovskite layer after annealing.

[0005] The purpose of the present invention is achieved by the following technical solutions: An annealing device, used for heating and crystallizing a perovskite layer, comprising: A radiation light source, used to generate radiation light, wherein the radiation light is used to heat the perovskite layer; A supporting platform, arranged opposite to the radiation light source and used to support the substrate with the perovskite layer attached thereto; A rough layer is provided on the side of the carrier platform facing the radiation light source. The rough layer is located on the side of the perovskite layer facing away from the radiation light source and receives radiation light penetrating the perovskite layer and scatters at least part of the radiation light to the perovskite layer.

[0006] Preferably, the rough layer is used to contact with the substrate, and the supporting platform supports the substrate in a contact manner, the root mean square of the height fluctuation of the rough layer is greater than 0.4 and less than 0.9, and the surface correlation length of the rough layer is 0.8~1.2 times the wavelength of the radiation light; the wavelength of the radiation light is 200nm~2μm.

[0007] Preferably, the thickness of the substrate is 2 mm to 3.5 mm, the size of the substrate is 300 mm×300 mm to 400 mm×500 mm, and the substrate is a glass substrate.

[0008] Preferably, the rough layer and the substrate are spaced apart, and the supporting platform supports the substrate in a non-contact manner, the spacing between the rough layer and the substrate is 1 μm~100 μm; the root mean square of the height fluctuation of the rough layer is greater than 0.6 and less than 0.8, and the surface correlation length of the rough layer is 0.8~1.2 times the wavelength of the radiation light; the wavelength of the radiation light is 380nm~10μm.

[0009] Preferably, the thickness of the substrate is 2 mm to 3.5 mm, the size of the substrate is 0.6 m×1 m to 1.2 m×2.4 m, and the substrate is a glass substrate.

[0010] Preferably, the substrate is FTO glass or ordinary glass; the perovskite layer is one or more of a MAPbI3 perovskite film, a FAPbI3 perovskite film, and a CsFAPbI3 perovskite film.

[0011] Preferably, the rough layer and the supporting platform are an integrated structure, or the rough layer is a thin film attached to the surface of the supporting platform, and the thin film material is a metal material.

[0012] Preferably, the rough layer is formed on the supporting platform by etching, sputtering or evaporation.

[0013] An annealing method, the annealing method is applied to any one of the above annealing devices, the annealing method comprising: The radiation light source generates radiation light that is irradiated toward the perovskite layer, part of the radiation light is absorbed by the perovskite layer, and part of the radiation light penetrates the perovskite layer and the substrate and irradiates the rough layer; The radiation light irradiated to the rough layer is scattered and reflected in the rough layer, and at least part of the scattered radiation light propagates to the perovskite layer and oscillates repeatedly to increase the optical path of the radiation light in the perovskite layer.

[0014] Preferably, the perovskite layer is pre-formed with a transparent mesophase film, and when the radiation light generated by the radiation light source passes through the perovskite layer, the transparent mesophase film absorbs part of the radiation light; Wherein, the radiation light is directed directly towards the target material.

[0015] Preferably, the substrate abuts against the rough layer, and the radiation light scattered at the rough layer passes through the substrate to enter the perovskite layer, wherein the power of the radiation light source is 450-550 W, and the scanning speed is 1-3 mm / s; Alternatively, the substrate is spaced from the rough layer to form a spacing space, and the radiation light scattered at the rough layer passes through the spacing space and the substrate to enter the perovskite layer, wherein the power of the radiation light source is 0.9~1.1kW and the scanning speed is 5~7mm / s.

[0016] Preferably, the perovskite layer absorbs the energy of the radiation light and gradually changes from a transparent state to a non-transparent state; before the perovskite layer changes to the non-transparent state, the radiation light generated by the radiation light source passes through the perovskite layer and then is scattered to the perovskite layer through the rough layer and oscillates repeatedly; when the perovskite layer changes to the non-transparent state, the radiation light generated by the radiation light source is directly absorbed by the perovskite layer, and the radiation light passing through the perovskite layer is reflected or scattered to the perovskite layer under the action of the rough layer and absorbed by the perovskite layer.

[0017] A method for preparing a perovskite layer, comprising: coating a perovskite precursor liquid on a substrate to form a perovskite layer; Preliminarily dissolving the perovskite layer so that the perovskite layer forms a transparent intermediate phase film; The perovskite layer on the substrate is annealed by any of the above annealing methods.

[0018] Compared with the prior art, the beneficial effects of the present invention include at least: By using radiation light as the energy source for annealing treatment, there is no need to set up an intermediate medium such as a glass substrate for heat transfer, avoiding deformation of the intermediate medium to cause uneven heat transfer, thereby effectively improving the crystal quality of the perovskite layer after annealing treatment. By setting a rough layer on the side of the carrier platform facing the radiation light source, when the radiation light is irradiated to the rough surface of the rough layer, part of the radiation light will be attenuated, and the attenuated radiation light will be scattered in all directions. At least part of the radiation light scattered by the rough layer is directed to the perovskite layer and oscillates repeatedly, so that the optical path of this part of the radiation light in the perovskite layer is significantly increased, and the absorption amount of the radiation light by the perovskite layer is increased, thereby improving the utilization rate of the radiation light and improving the crystal quality. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 is a schematic structural diagram of an annealing device according to an embodiment of the present invention; Figure 2 is a schematic structural diagram of an annealing device according to another embodiment of the present invention; Figure 3 1 is the absorption spectrum of Example 1, Comparative Example 1 and Comparative Example 2 of the present invention; Figure 4 is the absorption spectrum of Example 2, Comparative Example 1 and Comparative Example 2 of the embodiment of the present invention; Figure 5 is the absorption spectrum of Example 3, Comparative Example 1 and Comparative Example 2 of the embodiment of the present invention; Figure 6 It is the absorption spectrum of Example 4 and Comparative Example 1 of the present invention; Figure 7 It is the absorption spectrum of Example 5 and Comparative Example 1 of the embodiment of the present invention; Figure 8 is a 9-point absorption spectrum of Example 6 of the embodiment of the present invention; Fig. 9 It is a 9-point absorption spectrum of Comparative Example 3 of the embodiment of the present invention.

[0020] In the figure: 1. radiation light source; 2. support platform; 3. rough layer; 4. spacing space; 5. target material; 51. perovskite layer; 52. substrate. DETAILED DESCRIPTION

[0021] Example embodiments will now be described more fully with reference to the accompanying drawings. However, example embodiments can be implemented in a variety of forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided to make the present invention more comprehensive and complete and to fully convey the concepts of example embodiments to those skilled in the art. The same reference numerals in the figures represent the same or similar structures, and thus their repeated description will be omitted.

[0022] The words expressing positions and directions described in the present invention are all explained with reference to the accompanying drawings as examples, but they can be changed as needed, and all such changes are included in the protection scope of the present invention.

[0023] like Figure 1 and Figure 2As shown, the present invention provides an annealing device, which is used to anneal the target material 5. The target material 5 is light-transmitting, so that light can pass through the target material 5. The target material 5 can be a substrate 52 coated with a perovskite layer 51, and the substrate 52 can be a glass substrate or a substrate of other transparent materials. Specifically, the substrate 52 can be FTO (fluorine-doped tin oxide) glass or ordinary glass. Ordinary glass is a common glass that has not been doped or other treatments. The chemical composition of ordinary glass is Na2SiO3, CaSiO3, SiO2 or Na2O·CaO·6SiO2, etc.; the perovskite layer 51 can be one or more of a MAPbI3 perovskite film, a FAPbI3 perovskite film, and a CsFAPbI3 perovskite film. The perovskite layer 51 is light-transmitting, and the perovskite layer 51 can be formed by coating a liquid perovskite precursor solution on the substrate 52, and the perovskite layer 51 can be preliminarily desolvated in advance to form a transparent intermediate phase film. The annealing device is specifically used to anneal the perovskite layer 51 in the target material 5 to prepare the perovskite layer 51 into a desired perovskite layer. The desired perovskite layer is a perovskite layer 51 that condenses from a liquid state to a solid state after absorbing energy and forms an opaque layer structure. The annealing device includes a radiation light source 1 and a carrier 2.

[0024] The radiation light source 1 is used to generate radiation light, which is emitted from the radiation light source 1 toward the perovskite layer 51 of the target material 5. When the radiation light is irradiated onto the perovskite layer 51, the perovskite layer 51 can absorb the energy of the radiation light so that the radiation light can heat the perovskite layer 51 and anneal the perovskite layer 51. The radiation light source 1 can be an ultraviolet radiation source such as a mercury lamp or a xenon lamp, and the radiation light can be an ultraviolet radiation light; or, the radiation light source 1 can use other devices that can be used as a radiation annealing light source, for example, the radiation light source 1 uses other laser radiation sources such as an infrared radiation source or a microwave radiation source.

[0025] The support platform 2 is arranged opposite to the radiation light source 1, and the support platform 2 can support the substrate 52 in the target material 5 in a contact or non-contact manner. A rough layer 3 is provided on the side of the support platform 2 facing the radiation light source 1. The target material 5 can be arranged between the rough layer 3 and the radiation light. When the radiation light source 1 generates radiation light, the radiation light will be irradiated toward the target material 5. When the radiation light irradiates the target material 5, the perovskite layer 51 of the target material 5 hardly absorbs the radiation light, and the substrate 52 does not absorb the radiation light. Therefore, only a small part of the radiation light will be absorbed by the perovskite layer 51 to be used as an energy source for the annealing treatment of the perovskite layer 51, and a large part of the radiation light will penetrate the perovskite layer 51 and the substrate 52 of the target material 5 and propagate toward the coarse and rough layer 3 of the support platform 2. When the radiation light propagates to the rough layer 3, due to the uneven surface of the rough layer 3, part of the radiation light will be reflected along the original path, and part of the radiation light will be scattered.

[0026] The rough layer 3 may be an integrated structure with the carrier 2, for example, the carrier 2 forms the rough layer 3 by etching or other processes. Alternatively, the rough layer 3 may be a highly reflective thin film, and the rough layer 3 is attached to the carrier 2, for example, the rough layer 3 is formed on the carrier 2 by sputtering or evaporation. When the rough layer 3 is a thin film, the material of the thin film may be a metal material, for example, one of silver, copper, aluminum, tin, etc.; or, the thin film may also be made of other highly reflective materials.

[0027] In the partial radiation annealing device, the rough layer 3 is not provided on the carrier 2, and the surface of the carrier 2 is selected to be a smooth surface. When the radiation light passes through the target material 5 and irradiates the smooth surface, the radiation light is basically reflected by the smooth surface along the original path, and the radiation light reflected by the smooth surface passes through the target material 5 and dissipates in the environment. The optical path of the radiation light in the perovskite layer 51 of the target material 5 is related to the thickness of the perovskite layer 51. Due to the limited thickness of the perovskite layer 51, the optical path of the radiation light in the perovskite layer 51 is short, resulting in the perovskite layer 51 absorbing only part of the radiation light, while the rest of the radiation light is wasted. Among them, the original path of the radiation light is the illumination path when the radiation light passes through the target material 5 and is emitted to the carrier 2. Specifically, the radiation light passes through the target material 5 and is emitted to the carrier 2 along a vertical path, and the radiation light reflected by the carrier 2 is emitted to the target material 5 along the vertical path.

[0028] In the present application, a rough layer 3 is provided on the side of the carrier 2 facing the radiation light source 1, so that the surface of the rough layer 3 forms a rough surface. When the radiation light is irradiated to the rough surface of the rough layer 3, part of the radiation light will be reflected by the rough layer 3 along the original path, and the reflected radiation light will be emitted toward the target material 5 along the original path and pass through the target material 5, and the optical path of this part of the radiation light in the perovskite layer 51 is relatively short. Part of the radiation light will be attenuated, and the attenuated radiation light will be scattered in all directions. At least part of the radiation light scattered by the rough layer 3 will be emitted to the perovskite layer 51 of the target material 5 and oscillate repeatedly, so that the optical path of this part of the radiation light in the perovskite layer 51 is significantly increased, and the absorption amount of the radiation light by the perovskite layer 51 is increased, thereby improving the utilization rate of the radiation light and the crystallization quality. Among them, the path of the radiation light scattered from the rough layer 3 changes, the scattered radiation light enters the substrate 52 of the target material 5, passes through the substrate 52 and enters the perovskite layer 51, and is reflected by the perovskite layer 51 back to the substrate 52 and toward the rough layer 3; therefore, the radiation light can oscillate repeatedly. Specifically, the radiation light can be vertically directed to the target material 5, and then vertically pass through the perovskite layer 51 and the substrate 52 of the target material 5 and be directed to the rough layer 3. The radiation light is reflected and scattered at the rough layer 3. The reflected radiation light passes through the target material 5 along a vertical path, and the direction of the scattered radiation light changes. The scattered radiation light is directed to the perovskite layer 51 along an inclined path. When the scattered radiation light is directed from the lower surface of the perovskite layer 51 to the upper surface, it will be reflected to the rough layer 3 through the upper surface of the perovskite layer 51. The scattered radiation light repeats between the perovskite layer 51 and the rough layer 3, so that this part of the radiation light oscillates repeatedly.

[0029] The radiation reflected by the rough layer 3 is the mirror reflection component, which can also be called the coherent component, and the radiation scattered by the rough layer 3 is the diffuse component, which can also be called the incoherent component. When the roughness of the rough layer 3 is low, the coherent component is dominant, and the incoherent component is weak. At this time, only a small amount of radiation is scattered by the rough layer 3. When the roughness of the rough layer 3 is high, the incoherent component is dominant, and the coherent component is weak. At this time, a large amount of radiation is scattered by the rough layer 3.

[0030] Reference Figure 1 In some specific embodiments, the rough layer 3 is used to contact the target material 5, so that the support platform 2 can support the substrate 52 of the target material 5 in a contact manner. After the radiation light passes through the target material 5 and irradiates the rough layer 3, at least part of the radiation light scattered by the rough layer 3 re-enters the perovskite layer 51 of the target material 5 and oscillates repeatedly.

[0031] In addition, there may be some scattered radiation light that passes through the substrate 52 and is directly emitted from the substrate 52 to the outside without entering the perovskite layer 51. As the roughness of the rough layer 3 increases, the scattering range of the scattered radiation light generated under the action of the rough layer 3 is also larger. At this time, there are more radiation lights that are directly scattered into the environment without entering the perovskite layer 51. The wavelength λ of the radiation light and the roughness of the rough layer 3 will affect the scattering of the radiation light. In order to allow the radiation light scattered under the action of the rough layer 3 to enter the perovskite layer 51 to a greater extent and to increase the optical path of the radiation light in the perovskite layer 51 to a greater extent, so as to ensure the utilization efficiency of the radiation light, the height fluctuation root mean square δ of the rough layer 3 can be greater than 0.4 and less than 0.9, and the surface correlation length of the rough layer 3 can be greater than 0.4 and less than 0.9. is approximately the same as the wavelength of the radiated light, for example, the surface correlation length of the rough layer 3 It is 0.8 to 1.2 times the wavelength of the radiation light, and the wavelength of the radiation light can specifically be 200 nm to 2 μm.

[0032] Among them, the height fluctuation root mean square δ and the surface correlation length It is used to jointly characterize the roughness of the rough layer 3. The height fluctuation root mean square δ represents the relative to the average height The degree of deviation, .

[0033] In the calculation formula of the height fluctuation root mean square δ, is the vertical distance between the highest point and the lower surface of the rough layer 3 in the portion of the rough layer 3 located below the target material 5, that is, the maximum height of the rough layer 3, is the average height of each point in the part of the rough layer 3 located below the target material 5. When the rough layer 3 is a thin film structure with high reflectivity, the lower surface of the rough layer 3 is the contact surface between the rough layer 3 and the support platform 2; when the rough layer 3 and the support platform 2 are an integrated structure, the rough layer 3 can be assumed to have the same structure as the rough layer 3 of the thin film structure, and the virtual contact surface between the rough layer 3 and the support platform 2 is the lower surface of the rough layer 3. Surface correlation length Indicates the density of the surface undulations of the rough layer 3.

[0034] The physical surface height can be approximately regarded as following Gaussian distribution or exponential distribution. The horizontal distance on the surface of rough layer 3 is The degree of correlation between any two points is described by the autocorrelation function, and the Gaussian distribution correlation function is: , the exponential distribution function is: When r=0, ρ(r)= , as r increases, the ρ(r) value gradually decreases. When r approaches infinity, ρ(r) approaches 0. When the correlation coefficient ρ(r) drops to When the horizontal interval r between two points is defined as the surface correlation length .

[0035] When the rough layer 3 in the annealing device contacts the perovskite layer 51 of the target material 5, the annealing device can be used to anneal the target material 5 with a size of 300mm×300mm~400mm×500mm, that is, in the target material 5, the width of the substrate 52 and the perovskite layer 51 can both be 300mm~400mm, and the length of the substrate 52 and the perovskite layer 51 can both be 300mm~500mm. The thickness of the substrate 52 in the target material 5 can be 2mm~3.5mm, and the thickness of the perovskite layer 51 can be 400nm~650nm.

[0036] Reference Figure 2 In other specific embodiments, the rough layer 3 is spaced apart from the substrate 52 of the target material 5 to form a spacing space 4, so that the support platform 2 can support the substrate 52 of the target material 5 in a non-contact manner. By spacing the substrate 52 of the target material 5 from the rough layer 3, it is possible to avoid heat transfer when the substrate 52 contacts the rough layer 3, thereby avoiding the temperature difference at various locations of the substrate 52, thereby avoiding the influence of the temperature difference on the uniformity and quality of annealing. After passing through the target material 5, the radiation light passes through the spacing space 4 and irradiates the rough layer 3. At least part of the radiation light scattered by the rough layer 3 passes through the spacing space 4 and enters the perovskite layer 51 of the target material 5 and oscillates repeatedly. Among them, the carrier platform 2 can be provided with an air flotation device for supporting the substrate 52, and the substrate 52 of the target material 5 is spaced apart from the rough layer 3 by air flotation. At this time, the carrier platform 2 supports the substrate 52 of the target material 5 in a non-contact manner; or, the carrier platform 2 can also be provided with a clamping component, and the substrate 52 of the target material 5 can also be clamped and fixed above the rough layer 3 and spaced apart from the rough layer 3 by setting a clamping component, etc.; at this time, the carrier platform 2 supports the substrate 52 of the target material 5 in a contact manner, but only the clamping part of the clamping component of the carrier platform 2 is in contact with the substrate 52, and only a small area of ​​heat transfer is generated between the carrier platform 2 and the substrate 52, which effectively reduces the heat transfer generated when the substrate 52 contacts the carrier platform 2, thereby causing temperature differences at various locations of the substrate 52.

[0037] Part of the radiation light scattered by the rough layer 3 may pass through the spacing space 4 or the substrate 52 and directly emit to the outside without entering the perovskite layer 51. As the roughness of the rough layer 3 increases, the scattering range of the scattered radiation light generated by the rough layer 3 is also larger. At this time, more radiation light is directly scattered into the environment and enters the perovskite layer 51. The wavelength λ of the radiation light and the roughness of the rough layer 3 will affect the reflection and scattering of the radiation light. In addition, the height of the spacing space 4 will also affect the amount of scattered radiation light generated by the rough layer 3 directly entering the environment from the spacing space 4 or the substrate 52. In order to allow the radiation light scattered by the rough layer 3 to enter the perovskite layer 51 to a greater extent and increase the optical path of the radiation light in the perovskite layer 51 to a greater extent, so as to ensure the utilization efficiency of the radiation light, the spacing h between the rough layer 3 and the target material 5 can be 1μm~100μm. Preferably, the spacing h between the highest point of the rough layer 3 and the substrate 52 along the propagation direction of the radiation light is 1μm~100μm; the root mean square δ of the height fluctuation of the rough layer 3 can be greater than 0.6 and less than 0.8, and the surface correlation length of the rough layer 3 is approximately the same as the wavelength of the radiated light, for example, the surface correlation length of the rough layer 3 It is 0.8 to 1.2 times the wavelength of the radiation light, and the wavelength of the radiation light can specifically be 380 nm to 10 μm.

[0038] When the rough layer 3 in the annealing device is spaced apart from the substrate 52 of the target material 5, the annealing device can be used to anneal the target material 5 with a size of 0.6m×1m~1.2m×2.4m, that is, in the target material 5, the width of the substrate 52 and the perovskite layer 51 can both be 0.6m~1.2m, and the length of the substrate 52 and the perovskite layer 51 can both be 1m~2.4m. The thickness of the substrate 52 in the target material 5 can be 2mm~3.5mm, and the thickness of the perovskite layer 51 can be 400~650nm.

[0039] The present invention also provides an annealing method, which can be performed using the above annealing device. The annealing method includes step S01 and step S02, and can also include step S03.

[0040] Step S01 includes: the radiation light source 1 generates radiation light that irradiates toward the perovskite layer 51 of the target material 5, a small part of the radiation light is absorbed by the perovskite layer 51, and most of the radiation light penetrates the perovskite layer 51 and irradiates the rough layer 3. For example, the part of the radiation light that penetrates the perovskite layer 51 and irradiates the rough layer 3 is at least 10 times the part of the radiation light that is directly absorbed by the perovskite layer 51. Among them, the substrate 52 of the target material 5 can be in direct contact with the rough layer 3, and the radiation light sequentially penetrates the perovskite layer 51 and the substrate 52 of the target material 5 and then irradiates the rough layer 3. Alternatively, the target material 5 can be spaced apart from the rough layer 3 and a spacing space 4 is formed between the target material 5 and the rough layer 3, and the radiation light sequentially penetrates the perovskite layer 51 and the substrate 52 of the target material 5 and passes through the spacing space 4 and then irradiates the rough layer 3.

[0041] Step S02 includes: the radiation light irradiated to the rough layer 3 is scattered and reflected in the rough layer 3, and at least part of the scattered radiation light propagates to the perovskite layer 51 and oscillates repeatedly to increase the optical path of the radiation light in the perovskite layer 51. When the substrate 52 of the target material 5 is in direct contact with the rough surface, most of the scattered radiation light penetrates through the substrate 52 to penetrate into the perovskite layer 51 and oscillates repeatedly. Alternatively, when the substrate 52 of the target material 5 is spaced apart from the rough layer 3, most of the scattered radiation light penetrates through the spacing space 4 and the substrate 52 to penetrate into the perovskite layer 51 and oscillates repeatedly.

[0042] Step S03 includes: the perovskite layer 51 absorbs the energy of the radiation light and gradually changes from a transparent state to a non-transparent state; before the perovskite layer 51 changes to a non-transparent state, the radiation light generated by the radiation light source 1 passes through the perovskite layer 51 and is scattered to the perovskite layer 51 through the rough layer 3 and oscillates repeatedly; when the perovskite layer 51 changes to a non-transparent state, the radiation light generated by the radiation light source 1 is directly absorbed by the perovskite layer 51, and the radiation light passing through the perovskite layer 51 is reflected or scattered to the perovskite layer 51 under the action of the rough layer 3 and absorbed by the perovskite layer 51.

[0043] When the radiation light passes through the perovskite layer 51, the perovskite layer 51 absorbs part of the radiation light, and part of the radiation light passes through the perovskite layer 51 and the substrate 52 and then irradiates the rough layer 3. The radiation light is scattered at the rough layer 3, and most of the scattered radiation light enters the perovskite layer 51 again and oscillates repeatedly between the perovskite layer 51 and the rough layer 3, so as to effectively increase the optical path of the radiation light in the perovskite layer 51 and improve the efficiency of radiation annealing treatment of the perovskite layer 51.

[0044] In step S01, when the substrate 52 of the target material 5 is in contact with the rough layer 3, the radiation light scattered at the rough layer 3 passes through the substrate 52 to enter the perovskite layer 51. At this time, the power of the radiation light source 1 can be 450~550W, and the scanning speed of the radiation light source 1 can be 1~3mm / s; when the substrate 52 of the target material 5 is spaced from the rough layer 3 and forms a spacing space 4, the radiation light scattered at the rough layer 3 passes through the spacing space 4 and the substrate 52 to enter the perovskite layer 51. At this time, the power of the radiation light source 1 can be 0.9~1.1kW, and the scanning speed of the radiation light source 1 can be 5~7mm / s.

[0045] The perovskite layer 51 in the target component is pre-formed with a transparent intermediate phase film. When the radiation light is irradiated to the perovskite layer 51 , part of the radiation light is absorbed by the transparent intermediate phase film, and part of the radiation light passes through the transparent intermediate phase film and then irradiates to the rough layer 3 .

[0046] In the existing radiation annealing method, the optical path of the radiation light in the perovskite layer 51 is short, the perovskite layer 51 can only absorb a small amount of radiation light, and most of the energy of the radiation light is wasted. The annealing method of the present application scatters the radiation light passing through the perovskite layer 51 at the rough layer 3, and at least part of the scattered radiation light can be directed to the target material 5 and oscillate repeatedly, which effectively increases the optical path of the radiation light in the perovskite layer 51, thereby improving the absorption effect of the perovskite layer 51 on the radiation light, and improving the energy utilization rate of the radiation light, so that within a certain period of time, the perovskite layer 51 can absorb more energy from the radiation light, thereby improving the annealing efficiency and annealing quality. The annealing method of the present application generally only takes 2.5~3min to complete the annealing treatment of the perovskite layer 51.

[0047] In step S03, the perovskite layer 51 absorbs the energy of the radiation light and dries and crystallizes. The crystallized perovskite is in a non-transparent state. As the perovskite layer 51 continuously absorbs the energy of the radiation light, the crystallized portion of the perovskite layer 51 continuously increases, so that the perovskite layer 51 gradually changes from a transparent state to a non-transparent state. When the perovskite layer 51 changes to a non-transparent state, the perovskite layer 51 is in a partially dry or completely dry state.

[0048] Before the perovskite layer 51 is transformed into a non-transparent state, the radiation light can pass through the perovskite layer 51 and the substrate 52 to irradiate the rough layer 3, and then the rough layer 3 scatters the radiation light to the perovskite layer 51. When the perovskite layer 51 is transformed into a non-transparent state, the radiation light is directly absorbed by the perovskite layer 51 without passing through the perovskite layer 51, but the radiation light that passes through the perovskite layer 51 before the perovskite layer 51 is transformed into a non-transparent state may still exist between the perovskite layer 51 and the rough layer 3, and this part of the radiation light is reflected or scattered by the rough layer 3 to the perovskite layer 51 to be absorbed by the perovskite layer 51.

[0049] The present invention also provides a method for preparing a perovskite layer, comprising step S11, step S12 and step S13.

[0050] Step S11 includes: coating a perovskite precursor liquid on a substrate 52 to form a perovskite layer 51 .

[0051] Step S12 includes: performing preliminary desolventizing on the perovskite layer 51 so that the perovskite layer 51 forms a transparent intermediate phase film.

[0052] Step S13 includes: using the above-mentioned annealing method to anneal the perovskite layer 51 on the substrate 52 to obtain the desired perovskite layer.

[0053] In step S11, the perovskite precursor liquid may be a perovskite precursor liquid whose active ingredient is CsFAPbIBr or CsFAPbI3, or the perovskite precursor liquid may be other existing perovskite precursor liquids for preparing a perovskite layer. The perovskite precursor liquid may be coated on the substrate 52 by spin coating, slit coating, or blade coating to form a liquid film-like perovskite layer 51 on the substrate 52.

[0054] In step S12, the method for performing preliminary desolventization on the perovskite layer 51 can be any one of anti-solvent desolventization, VCD (Vacuum Concentration Drying) desolventization, and air knife desolventization. After the preliminary desolventization, the solution in the perovskite layer 51 is partially removed, so that a transparent intermediate phase film is formed in the perovskite layer 51. Example 1

[0055] Formamidine iodide, lead iodide, and cesium iodide in a mass ratio of 4.7:13:1 were dissolved in a mixed solution of NN-dimethylformamide and N-methylpyrrolidone in a volume ratio of 13:1, with a mass fraction of 44%, to obtain a perovskite precursor liquid with CsFAPbI3 as the active ingredient; the perovskite precursor liquid was coated on a substrate 52 by a slit coating process to form a perovskite layer 51. In the slit coating process, the coating head discharge speed was 20 μL / s, and the coating head moving speed was 28 mm / s; the thickness of the substrate 52 was 2 mm, and the size of the substrate 52 was 300 mm×300 mm.

[0056] The perovskite layer 51 is subjected to a VCD desolvation process, wherein the pressure of the VCD process is 5 Pa and the desolvation time is 30 s.

[0057] The perovskite layer 51 after dissolution is subjected to radiation annealing, specifically, laser annealing is selected, laser is used as the radiation light, and the wavelength of the laser is 450nm. A rough layer 3 is prepared on the aluminum support platform 2 by sputtering, and the height fluctuation root mean square δ of the rough layer 3 is 0.5, and the surface correlation length and wavelength, specifically, the surface correlation length The laser annealing power is 500W, the scanning speed is 2mm / s, and the annealing time is 2.5min. The substrate 52 is in contact with the rough layer 3. Example 2

[0058] This embodiment is basically the same as Embodiment 1, except that, in this embodiment, the perovskite layer 51 is desolventized by air knife desolventization. Specifically, the air knife desolventization is a wind knife suspended behind the coating head and bound to the coating head, and the wind knife moves with the coating head. The moving speed of the wind knife is specifically 5mm / s~50mm / s, the air inlet pressure of the wind knife is 0.1~0.6Mpa, and the distance between the wind knife outlet and the surface of the substrate 52 is 2-30mm. Example 3

[0059] This embodiment is basically the same as the embodiment 1, except that in this embodiment, the wavelength of the laser is 450 nm, the root mean square of the rough layer 3 is δ=2, and the surface correlation length is Smaller than the wavelength, the surface correlation length is 200nm. Example 4

[0060] This embodiment is basically the same as the embodiment 1, except that in this embodiment, the wavelength of the laser is 300 nm, the root mean square of the rough layer 3 is δ=0.5, and the surface correlation length is Same as wavelength, both are 300nm. Example 5

[0061] This embodiment is basically the same as the embodiment 1, except that in this embodiment, the wavelength of the laser is 1.5 μm, the root mean square of the rough layer 3 is δ=0.5, and the surface correlation length is The same as the wavelength, both are 1.5um. Example 6

[0062] Formamidine iodide, lead iodide, and cesium bromide in a mass ratio of 5.93:18.07:1 were dissolved in a mixed solution of NN-dimethylformamide and acetonitrile in a volume ratio of 9:1, with a mass fraction of 43.3%, to obtain a perovskite precursor liquid with an active ingredient of CsFAPbIBr; the perovskite precursor liquid was coated on a substrate 52 by a slit coating process to form a perovskite layer 51. In the slit coating process, the coating head had a liquid discharge speed of 40 μL / s and a coating head moving speed of 60 mm / s; the thickness of the substrate 52 was 2 mm, and the size of the substrate 52 was 0.6 m×1 m.

[0063] The perovskite layer 51 is desolvated by using an air knife, wherein the air knife moves at a speed of 10 mm / s, the air inlet pressure of the air knife is 0.5 MPa, and the distance between the air knife outlet and the surface of the substrate 52 is 3 mm.

[0064] The perovskite layer 51 after dissolution is subjected to radiation annealing, specifically, laser annealing is selected, laser is used as the radiation light, and the wavelength of the laser is 1.5 μm. The rough layer 3 is prepared on the aluminum support platform 2 by sputtering, and the height fluctuation root mean square δ of the rough layer 3 is 0.7, and the surface correlation length The wavelength is the same as 1.5 μm. The laser annealing power is 1 kW, the scanning speed is 6 mm / s, and the annealing time is 3 min. The substrate 52 is separated from the rough layer 3 by air floating design, and the spacing between the substrate 52 and the rough layer 3 is 80 μm. Comparative Example 1

[0065] This embodiment is basically the same as Embodiment 1, except that, in this embodiment, the perovskite layer 51 is annealed by hot plate annealing, the annealing temperature is 130° C., and the annealing time is 15 min. Comparative Example 2

[0066] This embodiment is basically the same as the embodiment 1, except that in this embodiment, the laser wavelength is 450nm. No rough layer 3 is formed on the surface of the support platform 2, that is, the root mean square of the surface of the support platform 2 is δ=0.08, and the surface correlation length Much larger than the wavelength, the surface correlation length Specifically 1mm. Comparative Example 3

[0067] This embodiment is basically the same as Embodiment 6, except that, in this embodiment, the substrate 52 is in direct contact with the rough layer 3 .

[0068] The perovskite layers prepared in the above examples and comparative examples were characterized by UV-visible absorption to obtain corresponding spectrum information. In the absorption spectrum, the horizontal axis is wavelength, in nm, and the vertical axis is absorbance, in L / (g·cm).

[0069] Reference Figure 3 , Figure 3 The spectrum information of the perovskite layer prepared in Example 1, Comparative Example 1 and Comparative Example 2 shows that the ultraviolet-visible light absorption of Example 1 is equivalent to that of Comparative Example 1, and the ultraviolet-visible light absorption of Example 1 is slightly stronger than that of Comparative Example 1. Compared with the hot plate annealing method in Comparative Example 1, the present application adopts radiation light for annealing, which greatly shortens the annealing time, and the quality of the perovskite layer prepared after annealing is also better. The ultraviolet-visible light absorption of Example 1 is significantly better than that of Comparative Example 2. It can be seen that by setting the rough layer 3, under the same radiation light and the same annealing time, the annealing efficiency and annealing quality can be significantly improved, so that the prepared perovskite layer has a higher light utilization rate.

[0070] Reference Figure 4 , Figure 4 The spectral information of the perovskite layers prepared in Example 2, Comparative Example 1 and Comparative Example 2 shows that the ultraviolet-visible light absorption of Example 2 is equivalent to that of Comparative Example 1, and the ultraviolet-visible light absorption of Example 2 is slightly stronger than that of Comparative Example 1, and the ultraviolet-visible light absorption of Example 2 is significantly better than that of Comparative Example 2.

[0071] Reference Figure 5 , Figure 5 The spectrum information of the perovskite layer prepared in Example 3, Comparative Example 1 and Comparative Example 2 shows that the ultraviolet visible light absorption of Example 3 is weaker than that of Comparative Example 1, and the ultraviolet visible light absorption of Example 3 is better than that of Comparative Example 2. It can be seen that when the height fluctuation root mean square δ is set larger so that the roughness of the rough surface is higher, the effect of the scattered radiation light on the annealing treatment of the perovskite layer 51 is slightly worse.

[0072] Reference Figure 6 and Figure 7 , Figure 6 The spectrum information of the perovskite layer prepared in Example 4 and Comparative Example 1, Figure 7 The spectrum information of the perovskite layer prepared in Example 5 and Comparative Example 1. It can be seen that the ultraviolet visible light absorption of Example 4 and Example 5 is equivalent to that of Comparative Example 1, and the ultraviolet visible light absorption of Example 4 and Example 5 is slightly stronger than that of Comparative Example 1.

[0073] Above Figures 3 to 7 In the figure, the spectrum information is the average value of the absorbance corresponding to the wavelength obtained by measuring multiple locations at each wavelength in the corresponding embodiment or comparative example, and the average value of the corresponding absorbance is obtained by measuring the average value of the corresponding absorbance at different wavelengths. Figures 6 to 9 The graph information in .

[0074] Reference Figures 8 to 9, Figure 8 The spectrum information is obtained by measuring 9 points on the perovskite layer prepared in Example 6. Fig. 9 The spectrum information is measured at 9 points on the perovskite layer prepared in Comparative Example 3. It can be seen that although the ultraviolet visible light absorption of Example 6 is equivalent to that of Comparative Example 3, the uniformity of the ultraviolet visible light absorption of Comparative Example 3 is significantly worse than that of Example 6. Specifically, after measurement, the ultraviolet visible light absorption uniformity of Example 6 is 1.61%, and the ultraviolet visible light absorption uniformity of Comparative Example 3 is 9.31%. Among them, the ultraviolet visible light absorption uniformity indicates the uniformity of ultraviolet visible light absorption at various locations of the perovskite layer. The smaller the uniformity, the more uniform the ultraviolet visible light absorption.

[0075] Although the embodiments of the present invention have been shown and described above, it is to be understood that the above embodiments are exemplary and are not to be construed as limitations on the present invention. A person skilled in the art may change, modify, substitute and modify the above embodiments within the scope of the invention without departing from the principles and purpose of the present invention. All such changes should fall within the scope of protection of the claims of the present invention.

Claims

1. An annealing device for heating and crystallizing a perovskite layer (51), characterized in that: include: A radiation light source (1) for generating radiation light, wherein the radiation light is used to heat the perovskite layer (51); A carrier platform (2), arranged opposite to the radiation light source (1), and used to support a substrate (52) to which the perovskite layer (51) is attached; A rough layer (3) is provided on the side of the carrier platform (2) facing the radiation light source (1); the rough layer (3) is located on the side of the perovskite layer (51) facing away from the radiation light source (1); and the rough layer (3) receives radiation light penetrating the perovskite layer (51) and scatters at least part of the radiation light to the perovskite layer (51).

2. The annealing device according to claim 1, characterized in that: The rough layer (3) is used to contact the substrate (52), and the support platform (2) supports the substrate (52) in a contact manner, the root mean square of the height fluctuation of the rough layer (3) is greater than 0.4 and less than 0.9, and the surface correlation length of the rough layer (3) is 0.8 to 1.2 times the wavelength of the radiation light; the wavelength of the radiation light is 200nm to 2μm.

3. The annealing device according to claim 2, characterized in that: The thickness of the substrate (52) is 2 mm to 3.5 mm, the size of the substrate (52) is 300 mm×300 mm to 400 mm×500 mm, and the substrate (52) is a glass substrate.

4. The annealing device according to claim 1, characterized in that: The rough layer (3) and the substrate (52) are spaced apart, and the support platform (2) supports the substrate (52) in a non-contact manner, the spacing between the rough layer (3) and the substrate (52) is 1 μm to 100 μm; the root mean square of the height fluctuation of the rough layer (3) is greater than 0.6 and less than 0.8, and the surface correlation length of the rough layer (3) is 0.8 to 1.2 times the wavelength of the radiation light; the wavelength of the radiation light is 380 nm to 10 μm.

5. The annealing device according to claim 4, characterized in that: The thickness of the substrate (52) is 2 mm to 3.5 mm, the size of the substrate (52) is 0.6 m×1 m to 1.2 m×2.4 m, and the substrate (52) is a glass substrate.

6. The annealing device according to claim 3 or 5, characterized in that: The substrate (52) is FTO glass or ordinary glass; the perovskite layer (51) is one or more of a MAPbI3 perovskite film, a FAPbI3 perovskite film, and a CsFAPbI3 perovskite film.

7. The annealing device according to claim 1, characterized in that: The rough layer (3) and the support platform (2) are an integrated structure, or the rough layer (3) is a thin film attached to the surface of the support platform (2), and the material of the thin film is a metal material.

8. The annealing device according to claim 1, characterized in that: The rough layer (3) is formed on the carrier platform (2) by etching, sputtering or evaporation.

9. An annealing method, characterized in that: The annealing method is applied to the annealing device according to any one of claims 1 to 8, and the annealing method comprises: The radiation light source (1) generates radiation light that is irradiated toward the perovskite layer (51), part of the radiation light is absorbed by the perovskite layer (51), and part of the radiation light penetrates the perovskite layer (51) and the substrate (52) and irradiates the rough layer (3); The radiation light irradiated onto the rough layer (3) is scattered and reflected on the rough layer (3), and at least part of the scattered radiation light propagates to the perovskite layer (51) and oscillates repeatedly, thereby increasing the optical path of the radiation light in the perovskite layer (51).

10. The annealing method according to claim 9, characterized in that: The perovskite layer (51) is pre-formed with a transparent intermediate phase film, and when the radiation light generated by the radiation light source (1) passes through the perovskite layer (51), the transparent intermediate phase film absorbs part of the radiation light; The radiation light is directed towards the target material (5).

11. The annealing method according to claim 10, characterized in that: The substrate (52) is in contact with the rough layer (3), and the radiation light scattered at the rough layer (3) passes through the substrate (52) to enter the perovskite layer (51), wherein the power of the radiation light source (1) is 450-550 W, and the scanning speed is 1-3 mm / s; Alternatively, the substrate (52) is spaced from the rough layer (3) to form a spacing space (4), and the radiation light scattered at the rough layer (3) passes through the spacing space (4) and the substrate (52) to enter the perovskite layer (51), wherein the power of the radiation light source (1) is 0.9-1.1 kW, and the scanning speed is 5-7 mm / s.

12. The annealing method according to claim 9, characterized in that: Also includes: The perovskite layer (51) absorbs the energy of the radiation light and gradually changes from a transparent state to a non-transparent state; Before the perovskite layer (51) is transformed into a non-transparent state, the radiation light generated by the radiation light source (1) passes through the perovskite layer (51) and is scattered to the perovskite layer (51) through the rough layer (3) and oscillates repeatedly; when the perovskite layer (51) is transformed into a non-transparent state, the radiation light generated by the radiation light source (1) is directly absorbed by the perovskite layer (51), and the radiation light passing through the perovskite layer (51) is reflected or scattered to the perovskite layer (51) under the action of the rough layer (3) and is absorbed by the perovskite layer (51).

13. A method for preparing a perovskite layer, characterized in that: include: coating a perovskite precursor liquid on a substrate (52) to form a perovskite layer (51); Preliminarily desolventizing the perovskite layer (51) so that the perovskite layer (51) forms a transparent intermediate phase film; The perovskite layer (51) on the substrate (52) is annealed using the annealing method according to any one of claims 9 to 12.

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