Pure-phase high-performance CsPbBr3Solar cell and preparation method thereof
阅读说明：本技术 一种纯相高性能CsPbBr3太阳电池及其制备方法 (Pure-phase high-performance CsPbBr3Solar cell and preparation method thereof ) 是由 朱卫东 巴延双 张泽阳 张春福 陈大正 张进成 郝跃 于 2021-07-26 设计创作，主要内容包括：本发明公开了一种纯相高性能CsPbBr-(3)太阳电池及其制备方法,所述制备方法包括：选取带有FTO电极阴极的玻璃衬底；在FTO电极阴极上制备TiO-(2)电子传输层,获得FTO/TiO-(2)基底；在TiO-(2)电子传输层上形成CsPb-(2)Br-(5)二维钙钛矿薄膜,获得FTO/TiO-(2)/CsPb-(2)Br-(5)基底；利用CsBr水溶液通过原位相变将CsPb-(2)Br-(5)二维钙钛矿薄膜转变为CsPbBr-(3)钙钛矿光吸收层,获得FTO/TiO-(2)/CsPbBr-(3)基底；在CsPbBr-(3)钙钛矿光吸收层上沉积碳电极阳极,获得纯相高性能CsPbBr-(3)太阳能电池。该制备方法基于原位相变,利用PbBr-(2)和CsBr生成二维钙钛矿CsPb-(2)Br-(5),而后通过原位相变方法将二维钙钛矿CsPb-(2)Br-(5)转变为纯相的三维钙钛矿CsPbBr-(3),依照该方法可以得到纯相的CsPbBr-(3)薄膜,且制备工艺简单、成本较低。(The invention discloses pure-phase high-performance CsPbBr 3 A solar cell and a method of fabricating the same, the method comprising: selecting a glass substrate with an FTO electrode cathode; preparation of TiO on FTO electrode cathode 2 Electron transport layer to obtain FTO/TiO 2 A substrate; in TiO 2 CsPb is formed on the electron transport layer 2 Br 5 Two-dimensional perovskite thin film to obtain FTO/TiO 2 /CsPb 2 Br 5 A substrate; CsPb by in-situ phase transition using CsBr aqueous solution 2 Br 5 Conversion of two-dimensional perovskite thin film into CsPbBr 3 Perovskite light absorption layer to obtain FTO/TiO 2 /CsPbBr 3 A substrate; in CsPbBr 3 Depositing carbon electrode anode on the perovskite light absorption layer to obtain pure phase high performance CsPbBr 3 A solar cell. The preparation method is based on in-situ phase change and utilizes PbBr 2 And CsBr to form two-dimensional perovskite CsPb 2 Br 5 Then, the two-dimensional perovskite CsPb is subjected to in-situ phase change 2 Br 5 Three-dimensional perovskite CsPbBr converted into pure phase 3 According to the method, pure-phase CsPbBr can be obtained 3 The film has simple preparation process and lower cost.)
1. Pure-phase high-performance CsPbBr3A method for manufacturing a solar cell, comprising:
selecting a glass substrate with an FTO electrode cathode;
preparing TiO on the cathode of the FTO electrode2Electron transport layer to obtain FTO/TiO2A substrate;
in the TiO2CsPb is formed on the electron transport layer2Br5Two-dimensional perovskite thin film to obtain FTO/TiO2/CsPb2Br5A substrate;
in-situ phase transition of CsPb by CsBr aqueous solution2Br5Conversion of two-dimensional perovskite thin film into CsPbBr3Perovskite light absorption layer to obtain FTO/TiO2/CsPbBr3A substrate;
in the CsPbBr3Depositing a carbon electrode anode on the perovskite light absorption layer to obtain the pure-phase high-performance CsPbBr3A solar cell.
2. The pure phase high performance CsPbBr of claim 13The preparation method of the solar cell is characterized in that glass with an FTO electrode cathode is selectedA substrate, comprising:
selecting a glass substrate with an FTO electrode cathode, and putting the glass substrate into Decon-90 aqueous solution, deionized water, acetone and absolute ethyl alcohol in sequence for ultrasonic cleaning for 15-30 min; subsequently, the cleaned glass substrate was placed in a UV-OZONE cleaner for ultraviolet OZONE treatment for 15 to 30 min.
3. The pure phase high performance CsPbBr of claim 13The preparation method of the solar cell is characterized in that TiO is formed on the cathode of the FTO electrode2An electron transport layer, obtaining an FTO/TiO2 substrate, comprising:
mixing 80-100 μ L of TiO2Spin-coating sol on the upper surface of the FTO electrode cathode for 30-60s at the rotating speed of 1500-3000rpm in an air environment;
annealing at 550 ℃ for 1-2h under the air environment of 450-2Electron transport layer to obtain FTO/TiO2A substrate.
4. The pure phase high performance CsPbBr of claim 13The method for preparing the solar cell is characterized in that the TiO2CsPb is formed on the electron transport layer2Br5Two-dimensional perovskite thin film to obtain FTO/TiO2/CsPb2Br5A substrate, comprising:
taking CsBr solid and PbBr with the mol ratio of 1:20-1:22Dissolving the solid in dimethylformamide solution to obtain CsPb2Br5Precursor solution;
in N2Taking 80-100 mu L CsPb in the atmosphere2Br5The precursor solution rotates at the speed of 1500-3000rpm in the FTO/TiO2Spin coating on the substrate for 30-60 s;
spin-coated with CsPb2Br5FTO/TiO of precursor solution2Annealing the substrate at 80-100 deg.C for 30-40min to form 200-400nm CsPb2Br5Film to obtain FTO/TiO2/CsPb2Br5A substrate.
5. The pure phase high performance CsPbBr of claim 13The preparation method of the solar cell is characterized in that CsPb is subjected to in-situ phase change by utilizing CsBr aqueous solution2Br5Conversion of two-dimensional perovskite thin film into CsPbBr3Perovskite light absorption layer to obtain FTO/TiO2/CsPbBr3A substrate, comprising:
dissolving CsBr solid in deionized water to obtain a CsBr water solution with the concentration of 212.8 mg/mL;
in the air room temperature environment, 70-100 μ L of the CsBr aqueous solution is rotated at 1500-3000rpm in the FTO/TiO2/CsPb2Br5Spin coating on the substrate for 30-60 s;
spin-coating FTO/TiO with CsBr solution2/CsPb2Br5Annealing the substrate at the temperature of 200-300 ℃ for 5-15min to form the CsPbBr with the thickness of 400-600nm3Perovskite light absorption layer, thereby obtaining the FTO/TiO2/CsPbBr3A substrate.
6. The pure phase high performance CsPbBr of claim 13The preparation method of the solar cell is characterized in that CsPbBr is added3Depositing a carbon electrode anode on the perovskite light absorbing layer, comprising:
under the room temperature environment, the CsPbBr is subjected to silk-screen printing3Depositing carbon slurry on the perovskite light absorption layer, and annealing for 15-30min at the temperature of 100-150 ℃ to form the carbon electrode anode with the thickness of 5-10 mu m.
7. Pure-phase high-performance CsPbBr3Solar cell, characterized in that it is made according to the manufacturing method of any one of claims 1 to 6, comprising, in order from bottom to top, a glass substrate, an FTO electrode cathode, TiO2Electron transport layer, CsPbBr3A perovskite light absorption layer and a carbon electrode anode.
8. The pure phase high performance CsPbBr prepared by the in situ phase transition two-step process of claim 73Solar cellThe method is characterized in that the thickness of the glass substrate is 1.5-2.5mm, the thickness of the FTO electrode cathode is 100-120nm, and the TiO is2The thickness of the electron transport layer is 50-80nm, and the CsPbBr is3The thickness of the perovskite light absorption layer is 400-600nm, and the thickness of the carbon electrode anode is 5-10 mu m.
Technical Field
The invention belongs to the technical field of perovskite solar cells, and particularly relates to pure-phase high-performance CsPbBr3A solar cell and a method for manufacturing the same.
Background
A perovskite solar cell is a solar cell using a perovskite-type organic metal halide semiconductor as a light absorbing material, and belongs to a third generation solar cell. The organic metal halide perovskite has the advantages of adjustable band gap, long carrier diffusion length, high mobility, low defect density and the like, and has a plurality of excellent optical and electrical properties. The perovskite solar cell has the efficiency equivalent to that of a silicon-based solar cell, and in addition, the perovskite solar cell becomes a hotspot in the research field of optoelectronic devices in recent years due to the potentials of high photoelectric conversion efficiency, simple preparation process, low cost and the like.
At present, organic-inorganic hybrid lead-halogen perovskites are easy to decompose and degrade under high temperature, high humidity or continuous illumination conditions because of the fact that the perovskite contains volatile and hydrophilic organic cation components. Therefore, under extreme conditions such as high temperature, high humidity, or continuous light, an organic-inorganic hybrid lead-halogen perovskite solar cell inevitably has a problem of poor reliability, while most perovskite photovoltaic devices include an organic charge transport layer and a metal electrode, and the former has a problem of poor stability. Furthermore, atoms in the device metal electrode tend to diffuse into the organic-inorganic hybrid lead-haloperovskite thin film/charge transport layerThe interface, which reacts chemically with the halogen in the film, further exacerbates device degradation. However, carbon-based CsPbBr3The inorganic perovskite solar cell completely avoids using an organic-inorganic hybrid lead-halogen perovskite material with poor stability, an organic charge transport material and a metal electrode, thereby becoming one of important approaches for overcoming the reliability problem of perovskite photovoltaic devices. In addition, since the metal electrode and the organic charge transport layer are replaced by the cheap carbon electrode, the manufacturing cost of the device is further reduced.
However, the current CsPbBr3The perovskite light absorption layer is generally prepared by adopting a one-step solution spin coating method or a two-step spin coating method, wherein the one-step preparation method is simple in process, but the film forming quality is low, and the adverse effect is generated on the performance of a device; CsPbBr preparation by two-step method3The film quality is improved, but pure-phase CsPbBr can not be prepared3Uncontrolled impurity phases are introduced into the thin film, rather than the pure phase thin film, which may generate defects and energy barriers, preventing carrier transport from affecting device performance.
Disclosure of Invention
In order to solve the problems in the prior art, the invention provides pure-phase high-performance CsPbBr3A solar cell and a method for manufacturing the same. The technical problem to be solved by the invention is realized by the following technical scheme:
one aspect of the invention provides pure-phase high-performance CsPbBr3A method of fabricating a solar cell, comprising:
selecting a glass substrate with an FTO electrode cathode;
preparing TiO on the cathode of the FTO electrode2Electron transport layer to obtain FTO/TiO2A substrate;
in the TiO2CsPb is formed on the electron transport layer2Br5Two-dimensional perovskite thin film to obtain FTO/TiO2/CsPb2Br5A substrate;
in-situ phase transition of CsPb by CsBr aqueous solution2Br5Conversion of two-dimensional perovskite thin film into CsPbBr3Perovskite light absorption layer to obtain FTO/TiO2/CsPbBr3A substrate;
in the CsPbBr3Depositing a carbon electrode anode on the perovskite light absorption layer to obtain the pure-phase high-performance CsPbBr3A solar cell.
In one embodiment of the present invention, a glass substrate with a cathode for an FTO electrode is selected comprising:
selecting a glass substrate with an FTO electrode cathode, and putting the glass substrate into Decon-90 aqueous solution, deionized water, acetone and absolute ethyl alcohol in sequence for ultrasonic cleaning for 15-30 min; subsequently, the cleaned glass substrate was placed in a UV-OZONE cleaner for ultraviolet OZONE treatment for 15 to 30 min.
In one embodiment of the present invention, TiO is formed on the cathode of the FTO electrode2Electron transport layer to obtain FTO/TiO2A substrate, comprising:
mixing 80-100 μ L of TiO2Spin-coating sol on the upper surface of the FTO electrode cathode for 30-60s at the rotating speed of 1500-3000rpm in an air environment;
annealing at 550 ℃ for 1-2h under the air environment of 450-2Electron transport layer to obtain FTO/TiO2A substrate.
In one embodiment of the invention, the TiO is2CsPb is formed on the electron transport layer2Br5Two-dimensional perovskite thin film to obtain FTO/TiO2/CsPb2Br5A substrate, comprising:
taking CsBr solid and PbBr with the mol ratio of 1:20-1:22Dissolving the solid in dimethylformamide solution to obtain CsPb2Br5Precursor solution;
in N2Taking 80-100 mu L CsPb in the atmosphere2Br5The precursor solution rotates at the speed of 1500-3000rpm in the FTO/TiO2Spin coating on the substrate for 30-60 s;
spin-coated with CsPb2Br5FTO/TiO of precursor solution2Annealing the substrate at 80-100 deg.C for 30-40min to form 200-400nm CsPb2Br5Film, obtainingFTO/TiO2/CsPb2Br5A substrate.
In one embodiment of the invention, the CsPb is converted by in situ phase transition using an aqueous CsBr solution2Br5Conversion of two-dimensional perovskite thin film into CsPbBr3Perovskite light absorption layer to obtain FTO/TiO2/CsPbBr3A substrate, comprising:
dissolving CsBr solid in deionized water to obtain a CsBr water solution with the concentration of 212.8 mg/mL;
in the air room temperature environment, 70-100 μ L of the CsBr aqueous solution is rotated at 1500-3000rpm in the FTO/TiO2/CsPb2Br5Spin coating on the substrate for 30-60 s;
spin-coating FTO/TiO with CsBr solution2/CsPb2Br5Annealing the substrate at the temperature of 200-300 ℃ for 5-15min to form the CsPbBr with the thickness of 400-600nm3Perovskite light absorption layer, thereby obtaining the FTO/TiO2/CsPbBr3A substrate.
In one embodiment of the invention, the CsPbBr is3Depositing a carbon electrode anode on the perovskite light absorbing layer, comprising:
under the room temperature environment, the CsPbBr is subjected to silk-screen printing3Depositing carbon slurry on the perovskite light absorption layer, and annealing for 15-30min at the temperature of 100-150 ℃ to form the carbon electrode anode with the thickness of 5-10 mu m.
On the other hand, the invention provides pure-phase high-performance CsPbBr3The solar cell is prepared according to the preparation method in any one of the above embodiments, and comprises a glass substrate, an FTO electrode cathode, and TiO which are sequentially distributed from bottom to top2Electron transport layer, CsPbBr3A perovskite light absorption layer and a carbon electrode anode.
In one embodiment of the invention, the thickness of the glass substrate is 1.5-2.5mm, the thickness of the FTO electrode cathode is 100-120nm, and the TiO electrode cathode is made of a metal oxide2The thickness of the electron transport layer is 50-80nm, and the CsPbBr is3The thickness of the perovskite light absorption layer is 400-600nm, and the thickness of the carbon electrode anode is 5-10 mu m.
Compared with the prior art, the invention has the beneficial effects that:
the pure phase high performance CsPbBr of the invention3The preparation method of the solar cell is based on in-situ phase change, and firstly PbBr is utilized2And CsBr to form two-dimensional perovskite CsPb2Br5Then to CsPb2Br5Adding CsBr aqueous solution dropwise, and carrying out in-situ phase change on the two-dimensional perovskite CsPb2Br5Three-dimensional perovskite CsPbBr converted into pure phase3And finally preparing the high-performance perovskite solar cell. CsPbBr prepared according to the method3The film has the advantage of excellent quality of the film prepared by the two-step method, and pure-phase CsPbBr can be obtained3The film simultaneously considers the requirements of manufacturing process difficulty and cost, and promotes CsPbBr3The efficiency of solar cells represents a strong application potential.
The present invention will be described in further detail with reference to the accompanying drawings and examples.
Drawings
FIG. 1 shows a pure phase CsPbBr with high performance according to an embodiment of the present invention3A flow schematic diagram of a preparation method of the solar cell;
FIGS. 2a to 2e show a pure phase CsPbBr with high performance according to an embodiment of the present invention3A preparation process schematic diagram of the solar cell;
FIG. 3 shows a pure-phase CsPbBr with high performance according to an embodiment of the present invention3A schematic structural diagram of a solar cell;
FIG. 4 is CsPbBr prepared by different methods3Efficiency of solar cells is plotted;
FIG. 5 is a pure phase high performance CsPbBr prepared by the method of the embodiment of the invention3CsPbBr of solar cell3Scanning Electron Microscope (SEM) images of the films.
Detailed Description
To further illustrate the technical means and effects of the present invention for achieving the predetermined objects, the following description, in conjunction with the accompanying drawings and the detailed description, provides a pure phase high performance CsPbBr according to the present invention3Solar cell and method for manufacturing the sameAnd (6) performing detailed description.
The foregoing and other technical matters, features and effects of the present invention will be apparent from the following detailed description of the embodiments, which is to be read in connection with the accompanying drawings. The technical means and effects of the present invention adopted to achieve the predetermined purpose can be more deeply and specifically understood through the description of the specific embodiments, however, the attached drawings are provided for reference and description only and are not used for limiting the technical scheme of the present invention.
It is noted that, herein, relational terms such as first and second, and the like may be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Also, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that an article or device that comprises a list of elements does not include only those elements but may include other elements not expressly listed. Without further limitation, an element defined by the phrase "comprising an … …" does not exclude the presence of additional like elements in the article or device comprising the element.
Example one
Referring to fig. 1 and fig. 2a to 2e, fig. 1 shows a pure phase high performance CsPbBr according to an embodiment of the present invention3A flow schematic diagram of a preparation method of the solar cell; FIGS. 2a to 2e show a pure phase CsPbBr with high performance according to an embodiment of the present invention3The preparation process of the solar cell is schematically shown. The preparation method comprises the following steps:
s1: a glass substrate with a cathode for the FTO electrode was selected.
Specifically, as shown in fig. 2a, a glass substrate with an FTO electrode cathode is selected and sequentially placed into a Decon-90 aqueous solution, deionized water, acetone, and absolute ethyl alcohol for ultrasonic cleaning for 15-30 min; subsequently, the cleaned glass substrate was placed in a UV-OZONE cleaner for ultraviolet OZONE treatment for 15 to 30 min.
In this example, the glass substrate with the cathode of the FTO electrode is dopedSnO of fluorine2Transparent conductive glass (SnO)2: F) wherein the thickness of the cathode of the FTO electrode is 100 nm-120 nm, and the thickness of the glass substrate excluding the cathode of the FTO electrode is 1.5 mm-2.5 mm.
The Decon-90 aqueous solution is a dikang Decon 90 alkaline cleaning solution, which is a surface active cleaning agent/radioactive contamination purifying agent, can be used for various purposes in laboratories, medical treatment and special industries, is provided in the form of a non-viscous concentrated liquid, is diluted with water, can be biodegraded and decomposed, can be rinsed completely and is not easy to burn.
S2: preparing TiO on the cathode of the FTO electrode2Electron transport layer to obtain FTO/TiO2A substrate.
Specifically, 80-100 μ L of TiO is mixed by a spin coater2Spin-coating (titanium dioxide) sol on the upper surface of the cathode of the FTO electrode treated by the UV-Ozone at the rotating speed of 1500-3000rpm in an air environment for 30-60 s; spin-on coating with TiO2The sample wafer is placed in a muffle furnace and annealed for 1-2h at 550 ℃ in an air atmosphere of 450-2Electron transport layer to form FTO/TiO2Substrate as shown in fig. 2 b.
S3: in the TiO2Preparation of CsPb on electron transport layer2Br5Two-dimensional perovskite thin film to obtain FTO/TiO2/CsPb2Br5A substrate.
Concretely, CsBr solid and PbBr are taken in a molar ratio of 1:20-1:22Dissolving the solid in dimethylformamide solution, stirring at normal temperature until the solid is completely dissolved to obtain CsPb2Br5Precursor solution; mixing the FTO/TiO2The substrate was placed in a glove box N2In the environment, 80-100 mu L of CsPb is taken2Br5The precursor solution is in the FTO/TiO at the rotating speed of 1500-2Spin coating on the substrate for 30-60 s; spin-coated with CsPb2Br5FTO/TiO of precursor solution2The substrate is placed on a hot bench at 80-100 ℃ for annealing for 30-40min to prepare the CsPb with the thickness of 200-400nm2Br5Thin film, and further obtaining FTO/TiO2/CsPb2Br5Substrate as shown in fig. 2 c.
S4: by usingThe CsPb aqueous solution of CsBr is subjected to in-situ phase change2Br5Conversion of thin films to CsPbBr3Perovskite light absorption layer to obtain FTO/TiO2/CsPbBr3A substrate;
specifically, the CsBr solid with the mass of 212.8mg is dissolved in 1mL of deionized water, and the solution is stirred at the normal temperature until the CsBr solid is completely dissolved to obtain a CsBr water solution with the concentration of 212.8 mg/mL; mixing the FTO/TiO2/CsPb2Br5The substrate is placed in an air room temperature environment, and 70-100 mu L of the CsBr aqueous solution is placed in the FTO/TiO at the rotating speed of 1500-2/CsPb2Br5Spin coating on the substrate for 30-60 s; spin-coating FTO/TiO with CsBr solution2/CsPb2Br5The substrate is placed on a 200-300 ℃ hot bench for annealing for 5-15min to prepare the CsPbBr with the thickness of 400-600nm3Perovskite light absorption layer, thereby obtaining the FTO/TiO2/CsPbBr3Substrate as shown in fig. 2 d.
S5: in the CsPbBr3Depositing carbon electrode anode on the perovskite light absorption layer to obtain pure phase high performance CsPbBr3A solar cell.
Specifically, the CsPbBr is subjected to silk-screen printing under room temperature environment3Depositing conductive carbon paste on the perovskite light absorption layer, and annealing for 15-30min on a hot bench at 100-150 ℃ to obtain the perovskite light absorption layer with the thickness of 5-10 mu m and the area of 0.085cm2To complete pure phase high performance CsPbBr3The solar cell was prepared as shown in figure 2 e.
In conclusion, the pure-phase high-performance CsPbBr of the embodiment3The solar cell preparation method is based on in-situ phase change and firstly utilizes PbBr2And CsBr to form two-dimensional perovskite CsPb2Br5Then to CsPb2Br5Adding CsBr aqueous solution dropwise, and carrying out in-situ phase change on the two-dimensional perovskite CsPb2Br5Three-dimensional perovskite CsPbBr converted into pure phase3And finally preparing the high-performance perovskite solar cell. CsPbBr prepared according to the method3The film has the advantage of excellent quality of the film prepared by the two-step method, and pure-phase CsPbBr can be obtained3Film, in combinationThe requirements of manufacturing process difficulty and cost are considered, and CsPbBr is improved3The efficiency of solar cells represents a strong application potential.
Example two
On the basis of the first embodiment, the embodiment provides pure-phase high-performance CsPbBr prepared by in-situ phase change3A method of fabricating a solar cell, the method comprising the steps of:
step 1: selecting a glass substrate with an FTO electrode cathode, and putting the glass substrate into Decon-90 aqueous solution, deionized water, acetone and absolute ethyl alcohol in sequence for ultrasonic cleaning for 15 min; subsequently, the cleaned glass substrate was placed in a UV-OZONE cleaner for ultraviolet OZONE treatment for 15 min.
In this example, the glass substrate with the cathode of the FTO electrode is SnO doped with fluorine2Transparent conductive glass (SnO)2: F) the thickness of the cathode of the FTO electrode is 100nm, and the thickness of the glass substrate excluding the cathode of the FTO electrode is 1.5 mm.
Step 2: 80 μ L of TiO was homogenized using a homogenizer2Spin-coating (titanium dioxide) sol on the upper surface of the cathode of the FTO electrode treated by the UV-OZONE for 30s at the rotating speed of 3000rpm in an air environment; spin-on coating with TiO2The sample wafer is placed in a muffle furnace and annealed for 1h at 500 ℃ in an air atmosphere to obtain TiO with the thickness of 80nm2Electron transport layer to form FTO/TiO2A substrate.
And step 3: taking CsBr solid and PbBr with the mol ratio of 1:20-1:22Dissolving the solid in dimethylformamide solution, stirring at normal temperature until the solid is completely dissolved to obtain CsPb2Br5Precursor solution; mixing the FTO/TiO2The substrate was placed in a glove box N2In the environment, 80 μ L of CsPb was taken2Br5The precursor solution is put in the FTO/TiO at the rotating speed of 3000rpm2Spin coating on the substrate for 30 s; spin-coated with CsPb2Br5FTO/TiO of precursor solution2The substrate is placed on a hot bench at 80-100 ℃ for annealing for 30-40min to prepare the CsPb with the thickness of 200-400nm2Br5Thin film, and further obtaining FTO/TiO2/CsPb2Br5A substrate.
In this example, CsBr solid and PbBr were taken2The molar ratio of solids was 1: 20. Specifically, take CsBr solid with a mass of 10.6mg and PbBr with a mass of 367mg2The solid was dissolved in 1mL of dimethylformamide.
And 4, step 4: dissolving the CsBr solid with the mass of 212.8mg in 1mL of deionized water, and stirring at normal temperature until the CsBr solid is completely dissolved to obtain a CsBr water solution with the concentration of 212.8 mg/mL; mixing the FTO/TiO2/CsPb2Br5The substrate was placed in an air room temperature environment and 80. mu.L of the above CsBr aqueous solution was spun at 2000rpm on the FTO/TiO substrate2/CsPb2Br5Spin coating on the substrate for 30 s; spin-coating FTO/TiO with CsBr solution2/CsPb2Br5The substrate is placed on a hot bench at 250 ℃ for annealing for 5min to prepare CsPbBr with the thickness of 400nm3Perovskite light absorption layer, thereby obtaining the FTO/TiO2/CsPbBr3A substrate.
And 5: under the room temperature environment, the CsPbBr is subjected to silk-screen printing3Depositing conductive carbon paste on the perovskite light absorption layer, and annealing at 120 deg.C for 15min to obtain a film with a thickness of 5-10 μm and an area of 0.085cm2To complete pure phase high performance CsPbBr3And (4) preparing the solar cell.
EXAMPLE III
On the basis of the above embodiments, the present embodiment provides a pure phase high performance CsPbBr3A solar cell prepared using the method of preparation described in the above example. Referring to fig. 3, fig. 3 is a schematic structural diagram of a pure-phase high-performance CsPbBr3 solar cell according to an embodiment of the present invention. The pure phase high performance CsPbBr3The solar cell includes: a glass substrate 1, an FTO electrode cathode 2 and TiO which are distributed from bottom to top in sequence2Electron transport layer 3, CsPbBr3A thin film 4 of CsPbBr3A carbon electrode anode 5 is provided above the perovskite light absorption layer 4. Wherein the thickness of the glass substrate 1 is 1.5 mm-2.5 mm, the thickness of the FTO electrode cathode 2 is 100 nm-120 nm, and the TiO is2The thickness of the electron transmission layer 3 is 50 nm-80 nm, and CsPbBr3The thickness of the perovskite light absorption layer 4 is 400 anm-600 nm, the thickness of the carbon electrode anode 5 is 5-10 μm, and the area is 0.085cm2。
The pure phase high performance CsPbBr prepared by the embodiment of the invention is further illustrated by the comparative experiment below3Performance of the solar cell. Referring to FIGS. 4 and 5, FIG. 4 shows CsPbBr prepared by different methods3Efficiency of solar cells is plotted; wherein w/o CsBr represents the existing one-step solution spin coating method, w/CsBr 0.05mol and w/CsBr 0.1mol are both the method of the embodiment, and w/CsBr 0.05mol represents 1mol of PbBr in step 320.05mol CsBr is added, w/CsBr 0.1mol means that 1mol PbBr is added in step 320.1mol CsBr was added thereto. It is obvious that first use PbBr2And CsBr to form two-dimensional perovskite CsPb2Br5Then to CsPb2Br5Adding CsBr aqueous solution dropwise, and carrying out in-situ phase change on the two-dimensional perovskite CsPb2Br5Three-dimensional perovskite CsPbBr converted into pure phase3The performance of the prepared solar cell is obviously improved.
Referring to fig. 5, fig. 5 is an SEM image of the CsPbBr3 thin film of the pure-phase high-performance CsPbBr3 solar cell prepared by the method of the embodiment of the present invention, wherein the left side image is the image obtained by adding PbBr to the CsPbBr3 thin film in step 32CsPbBr prepared by doping 0.05mol CsBr into solution3SEM photograph of the film, right side view is to PbBr in step 32CsPbBr prepared by doping 0.1mol CsBr into solution3As seen from the SEM picture of the film, the film prepared by doping 0.1mol of CsBr has better crystallinity and larger grain size, which corresponds to the solar cell efficiency shown in FIG. 4. The film prepared by adding 0.1mol of CsBr has better crystallinity, so that more excellent solar cell performance is obtained, and the influence of different CsBr doping doses on the solar cell performance in different embodiments can be seen.
Pure phase high performance CsPbBr of this example3The solar cell preparation method is based on in-situ phase change and firstly utilizes PbBr2And CsBr to form two-dimensional perovskite CsPb2Br5Then to CsPb2Br5Adding CsBr aqueous solution dropwise, and carrying out in-situ phase change on the two-dimensional perovskite CsPb2Br5Three-dimensional perovskite CsPbBr converted into pure phase3And finally preparing the high-performance perovskite solar cell. CsPbBr prepared according to the method3The film has the advantage of excellent quality of the film prepared by the two-step method, and pure-phase CsPbBr can be obtained3The film simultaneously considers the requirements of manufacturing process difficulty and cost, and promotes CsPbBr3The efficiency of solar cells represents a strong application potential.
The foregoing is a more detailed description of the invention in connection with specific preferred embodiments and it is not intended that the invention be limited to these specific details. For those skilled in the art to which the invention pertains, several simple deductions or substitutions can be made without departing from the spirit of the invention, and all shall be considered as belonging to the protection scope of the invention.