A high photoelectric conversion rate perovskite battery and preparation method thereof

Abstract

The invention discloses a high photoelectric conversion rate perovskite cell and a preparation method thereof. The structure of the perovskite cell is sequentially composed of an FTO conductive glass layer, an electron transport layer, a perovskite light absorption layer, a strontium chloride film layer, a hole transport layer and a gold electrode layer; the material of the electron transport layer is titanium dioxide or tin dioxide. The high photoelectric conversion rate perovskite cell of the invention prepares a layer of strontium salt film modification layer on the surface of the perovskite light absorption layer as an interface modification layer to form a barrier layer for ion migration. The addition of the strontium salt film modification layer significantly improves the photoelectric performance of the perovskite solar cell, so that the photoelectric conversion efficiency of the perovskite cell can reach 21.11%. The stability of the perovskite cell of the invention is significantly improved, which is helpful to promote the commercialization of the perovskite cell.

Description

Technical Field

[0001] The present invention relates to the technical field of the preparation of organic-inorganic halide perovskite thin film batteries, and specifically relates to a perovskite battery with high photoelectric conversion efficiency and a preparation method thereof. Background Art

[0002] As the third-generation solar cell industry, perovskite batteries have developed rapidly in recent years, and the photoelectric conversion efficiency has increased from the initial 3.8% to 25.2%. Therefore, perovskite materials may become a powerful alternative to silicon-based solar cells in the future and also play a key role in LEDs and photodetectors. The research and development of perovskite materials have continuously refreshed the world record, and the battery structures are also diverse, including planar n-i-p structures, mesoporous n-i-p structures, and inverted p-i-n structures. However, the stability of perovskite batteries under long-term working conditions is still at a relatively low level. The main factors affecting device stability include external factors such as humidity and air, and internal influencing factors include the hygroscopicity, thermal instability, and ion migration of the materials. The former alleviates the influence of factors such as moisture, oxygen, and light in the air through advanced encapsulation technologies, while the internal factors need to be solved by adjusting the bandgap structure of perovskite materials, appropriate dopants, and interfacial material modification layers.

[0003] Due to the application of a high external field to the thin film during current-voltage scanning, ion migration in halide perovskites is almost inevitable, and the situation is more serious at grain boundaries and interfaces. This phenomenon will lead to the hysteresis effect of the battery and the attenuation of device performance. Therefore, by adding a suitable interfacial material modification layer between the perovskite light-absorbing layer and the hole transport layer, the ion migration barrier is increased, thereby reducing the occurrence of ion migration, effectively improving the crystallization of perovskite crystals and surface passivation, and thus reducing the generation of defect states, and further improving the optoelectronic performance of the device. Most of the previous studies have focused on the help of interfacial material modification layers in improving the battery hysteresis effect and defect states, but the research on the stability of perovskite devices still needs to be urgently solved. Summary of the Invention

[0004] The purpose of the present invention is to provide a perovskite battery with high photoelectric conversion efficiency for the deficiencies in the above-mentioned prior art.

[0005] Another purpose of the present invention is to provide a preparation method of a perovskite battery with high photoelectric conversion efficiency.

[0006] The purpose of the present invention is achieved through the following technical solutions:

[0007] A perovskite battery with high photoelectric conversion efficiency, the structure of the perovskite battery is successively an FTO conductive glass layer, an electron transport layer, a perovskite light-absorbing layer, a strontium chloride thin film layer, a hole transport layer, and a gold electrode layer; the material of the electron transport layer is titanium dioxide or tin dioxide.

[0008] In a further design of the present invention, the perovskite light-absorbing layer material is FA x MA 1-x PbI x Br 1-x , where 0 ≤ x ≤ 1.

[0009] In a further design of the present invention, the hole transport layer material is poly[bis(4-phenyl)(2,4,6-trimethylphenyl)amine] (PTAA) or 2,2,7,7-tetra[N,N-bis(4-methoxyphenyl)amino]-9,9-spirobifluorene (Spiro-oMeTAD).

[0010] The preparation method of the above high-photovoltaic conversion rate perovskite solar cell includes the following specific steps:

[0011] Step 1, clean the FTO conductive glass: successively clean the FTO conductive glass with glass cleaning agent, acetone, isopropanol, absolute ethanol, and deionized water by ultrasonic wave, and after drying, use a nitrogen gun to remove the impurities on the surface of the FTO conductive glass;

[0012] Step 2, prepare the electron transport layer: spin-coat the electron transport layer material on the FTO conductive glass and perform annealing treatment;

[0013] Step 3, prepare the perovskite light-absorbing layer: prepare the perovskite light-absorbing material into a solution according to the one-step solution method, spin-coat the perovskite light-absorbing material on the electron transport layer, the first rotation speed is 1000 rpm, the time is 10 s, the second-stage rotation speed is 4000 rpm, the time is 30 s, and 10 s after the second-stage rotation speed, quickly pipette diethyl ether and drop it onto the perovskite light-absorbing layer and perform annealing treatment. The perovskite light-absorbing material is FA x MA 1-x PbI x Br 1-x , where 0 ≤ x ≤ 1;

[0014] Step 4, prepare the strontium salt thin film layer: spin-coat the strontium salt solution on the perovskite light-absorbing layer and perform annealing treatment. The strontium salt solution is strontium chloride solution;

[0015] Step 5, prepare the hole transport layer: spin-coat the hole transport material on the strontium salt thin film layer. The hole transport material is poly[bis(4-phenyl)(2,4,6-trimethylphenyl)amine] or 2,2,7,7-tetra[N,N-bis(4-methoxyphenyl)amino]-9,9-spirobifluorene;

[0016] Step 6, evaporate a gold electrode on the hole transport layer.

[0017] In a further design solution of the present invention, the electron transport layer material in step 2 is a titanium dioxide solution, which is prepared from diisopropyl dititanate and anhydrous n-butanol in a volume ratio of 1:(10 - 20), the annealing temperature is 450 - 500 °C, and the annealing time is 60 - 90 min.

[0018] In a further design solution of the present invention, the electron transport layer material in step 2 is a tin dioxide hydrosol solution, which is prepared from a 15% hydrosol dispersion and deionized water in a volume ratio of 1:(4 - 10), the annealing temperature is 140 - 150 °C, and the annealing time is 30 - 40 min.

[0019] In a further design solution of the present invention, the molar concentration of the strontium chloride solution in step 4 is 0.5 - 2.0 mmol / L.

[0020] In a further design solution of the present invention, when the strontium salt solution is spin-coated on the perovskite light-absorbing layer in step 4, the strontium salt solution is first allowed to stand for 10 - 15 s, the rotation speed during spin-coating is 3000 - 5000 rpm, the annealing temperature is 110 - 115 °C, and the annealing time is 5 - 10 min.

[0021] The present invention has the following outstanding beneficial effects:

[0022] In the high-photovoltage-conversion perovskite solar cell of the present invention, a strontium salt thin film modification layer is prepared on the surface of the perovskite light-absorbing layer as an interfacial modification layer to form a barrier layer for ion migration. The addition of the strontium salt thin film modification layer significantly improves the optoelectronic performance of the perovskite solar cell, enabling the photoelectric conversion efficiency of the perovskite solar cell to reach 21.11%. Compared with existing perovskite solar cells, the average value exceeds 20%. At the same time, the voltage of the perovskite solar cell containing the strontium salt thin film modification layer increases from 1.00 V of the existing perovskite solar cell to 1.09 V, which enhances the passivation effect of the perovskite solar cell and effectively suppresses non-radiative recombination. The perovskite solar cell of the present invention can effectively solve the ion migration problem of methylamine and formamidine materials in the crystal structure, improve the photoelectric conversion efficiency and device hysteresis effect of the perovskite solar cell, and at the same time improve the stability of the device. In the optoelectronic performance test under continuous dry air for 1000 h, the perovskite solar cell containing the strontium salt thin film modification layer always maintains a high photoelectric conversion efficiency. The stability of the perovskite solar cell of the present invention is significantly improved, which helps to promote the commercialization of perovskite solar cells. The preparation method of the high-photovoltage-conversion perovskite solar cell of the present invention is simple and easy to operate, and is prepared in air with strong repeatability. Description of the Drawings

[0023] Figure 1 It is a graph showing the optoelectronic performance test results of the high-photovoltage-conversion perovskite solar cell and the comparative perovskite solar cell in forward and reverse scans in Example 1;

[0024] Figure 2 It is the graph of the continuous optoelectronic performance test results of the high-photovoltaic conversion rate perovskite battery and the comparative perovskite battery in Example 1 under dry air for 1000 h;

[0025] Figure 3 It is the SEM image of Test Piece A in the detection example;

[0026] Figure 4 It is the SEM image of Test Piece B in the detection example;

[0027] Figure 5 It is the fluorescence emission image of Test Piece A and Test Piece B in the detection example;

[0028] Figure 6 It is the thin film fluorescence lifetime image of Test Piece A and Test Piece B in the detection example;

[0029] Figure 7 It is the thin film fluorescence lifetime image of Test Piece A and Test Piece B in the detection example;

[0030] Figure 8 It is the ultraviolet absorption image of the thin films of Test Piece C and Test Piece D in the detection example;

[0031] Figure 9 It is the XPS energy spectrum image of I in the thin films of Test Piece C and Test Piece D in the detection example;

[0032] Figure 10 It is the XPS energy spectrum image of Pb in the thin films of Test Piece C and Test Piece D in the detection example. Detailed implementation manners

[0033] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0034] Example 1

[0035] Step 1: Cleaning of FTO conductive glass: Successively ultrasonic clean with glass cleaning agent, acetone, isopropyl alcohol, absolute ethanol, and deionized water for 20 min, dry after cleaning, and remove surface impurities with a nitrogen gun.

[0036] Step 2: Preparation of electron transport layer: Prepare a TiO 2 solution according to the volume ratio of diisopropyl titanate to anhydrous n-butanol of 1:20, spin-coat the TiO 2 solution on the FTO conductive glass, and anneal at 500 °C for 90 min.

[0037] Step 3: Preparation of perovskite light-absorbing layer: Mix FA 0.95 MA 0.05 PbI 0.95 Br 0.05The perovskite light-absorbing material is spin-coated on the electron transport layer by a one-step solution method at a first rotation speed of 1000 rpm for 10 s, and a second-stage rotation speed of 4000 rpm for 30 s. After 10 s of the second-stage rotation speed, 1000 μL of diethyl ether is taken and quickly dropped onto the perovskite light-absorbing layer, and annealed at 150 °C for 15 min.

[0038] Step 4: Preparation of the strontium salt thin film layer: Take 500 μL of a strontium salt solution with a molar concentration of 1.10 mmol / L, spin-coat at 4000 rpm after standing for 10 s, and anneal at 115 °C for 10 min.

[0039] Step 5: Preparation of the hole transport layer: Spin-coat Spiro-OMeTAD on the above-mentioned strontium salt thin film layer.

[0040] Step 6: Evaporate a gold electrode on the hole transport layer to obtain a perovskite solar cell with high photoelectric conversion efficiency.

[0041] To test the performance of the perovskite solar cell with high photoelectric conversion efficiency, a comparative perovskite solar cell is fabricated according to the following steps:

[0042] Step 1: Cleaning of the FTO conductive glass: Ultrasonically clean with a glass cleaning agent, acetone, isopropyl alcohol, absolute ethanol, and deionized water in sequence for 20 min. After cleaning, dry it and remove the surface impurities with a nitrogen gun.

[0043] Step 2: Preparation of the electron transport layer: Prepare a TiO 2 solution according to the volume ratio of diisopropyl titanate to anhydrous n-butanol of 1:20, and spin-coat the TiO 2 solution on the FTO conductive glass, and anneal at 500 °C for 90 min.

[0044] Step 3: Preparation of the perovskite light-absorbing layer: Spin-coat the FA 0.95 MA 0.05 PbI 0.95 Br 0.05 perovskite light-absorbing material on the electron transport layer by a one-step solution method at a first rotation speed of 1000 rpm for 10 s, and a second-stage rotation speed of 4000 rpm for 30 s. After 10 s of the second-stage rotation speed, 1000 μL of diethyl ether is taken and quickly dropped onto the above process, and annealed at 150 °C for 15 min.

[0045] Step 4: Preparation of the hole transport layer: Spin-coat Spiro-OMeTAD on the above-mentioned perovskite light-absorbing layer.

[0046] Step 5: Evaporate a gold electrode on the hole transport layer to obtain a comparative perovskite solar cell.

[0047] The preparation steps of the comparative perovskite solar cell are one step less than the preparation of the strontium salt thin film layer, and the remaining steps and methods are exactly the same as above.

[0048] The perovskite solar cell with high photoelectric conversion rate obtained in Example 1 and the comparative perovskite solar cell were subjected to forward and reverse scan photoelectric performance tests, and the results are shown in Table 1 and Figure 1 .

[0049] Table 1

[0050]

[0051] As can be seen from Table 1 and Figure 1 , the forward and reverse scan results of the perovskite solar cell with high photoelectric conversion rate obtained in Example 1 are almost the same, indicating that the hysteresis effect of the perovskite solar cell device modified with the strontium salt thin film layer is reduced, and the photoelectric conversion efficiency is significantly increased. The forward and reverse scan photoelectric conversion efficiencies of the perovskite solar cell with high photoelectric conversion rate obtained in Example 1 are significantly improved compared with those of the comparative perovskite solar cell device.

[0052] The perovskite solar cell with high photoelectric conversion rate obtained in Example 1 and the comparative perovskite solar cell were subjected to continuous photoelectric performance tests for 1000 h in dry air, and the results are shown in Figure 2 .

[0053] As Figure 2 shown, after 1000 h of continuous photoelectric performance test, the battery performance of the perovskite solar cell with high photoelectric conversion rate obtained in Example 1 retained more than 80% of the original, while the battery performance of the comparative perovskite solar cell without the strontium salt modification layer had decayed to less than 20% of the original after 800 h, which confirmed that the battery device of the perovskite solar cell of the present invention had higher long-term stability.

[0054] Example 2

[0055] Step 1: Cleaning of FTO conductive glass: The FTO conductive glass was successively ultrasonically cleaned with glass cleaning agent, acetone, isopropanol, absolute ethanol, and deionized water for 20 min, dried after cleaning, and the surface impurities were removed with a nitrogen gun.

[0056] Step 2: Preparation of electron transport layer: A TiO 2 solution was prepared according to the volume ratio of diisopropyl titanate to anhydrous n-butanol of 1:14, and the TiO 2 solution was spin-coated on the FTO conductive glass and annealed at 500 °C for 60 min.

[0057] Step 3: Preparation of perovskite light-absorbing layer: FA 0.95 MA 0.05 PbI 0.95 Br 0.05The perovskite light-absorbing material is spin-coated on the electron transport layer by the one-step solution method. The first rotation speed is 1000 rpm for 10 s, the second-stage rotation speed is 4000 rpm for 30 s. After 10 s of the second-stage rotation speed, 500 μL of ethyl ether is taken and quickly dropped onto the perovskite light-absorbing layer, and annealed at 150 °C for 10 min.

[0058] Step 4: Preparation of the strontium salt thin film layer: Take 200 μL of strontium salt solution with a molar concentration of 0.5 mmol / L, spin-coat at 3000 rpm after standing for 10 s, and anneal at 110 °C for 5 min.

[0059] Step 5: Preparation of the hole transport layer: Spin-coat Spiro-OMeTAD on the strontium salt thin film layer described in Step 4.

[0060] Step 6: Evaporate a gold electrode on the hole transport layer to obtain a perovskite solar cell with high photoelectric conversion efficiency.

[0061] Example 3

[0062] Step 1: The same as Step 1 in Example 1.

[0063] Step 2: Preparation of the electron transport layer: Spin-coat the SnO2 solution (15% aqueous colloid dispersion and deionized water in a volume ratio of 1:4) on the FTO conductive glass, and anneal at 140 °C for 30 min.

[0064] Step 3: Preparation of the perovskite light-absorbing layer: FA 0.95 MA 0.05 PbI 0.95 Br 0.05 The perovskite light-absorbing material is spin-coated on the electron transport layer in Step 2 by the classical one-step solution method. The first rotation speed is 1000 rpm for 10 s, the second-stage rotation speed is 4000 rpm for 30 s. After 10 s of the second-stage rotation speed, 600 μL of ethyl ether is taken and quickly dropped onto the perovskite light-absorbing layer, and annealed at 150 °C for 10 min.

[0065] Step 4: Preparation of the strontium salt thin film layer: Take 200 μL of strontium salt solution with a molar concentration of 0.5 mmol / L, spin-coat at 3000 rpm after standing for 10 s, and anneal at 110 °C for 5 min.

[0066] Step 5: Preparation of the hole transport layer: Spin-coat Spiro-OMeTAD on the strontium salt thin film layer described in Step 4.

[0067] Step 6: Evaporate a gold electrode on the hole transport layer.

[0068] Example 4

[0069] Step 1: The same as Step 1 in Example 1.

[0070] Step 2: Preparation of the electron transport layer: TiO 2 solution (the volume ratio of diisopropyl dititanate to anhydrous n-butanol is 1:16) is spin-coated on the FTO conductive glass and annealed at 450 °C for 60 min.

[0071] Step 3: Preparation of the perovskite light-absorbing layer: FA 0.85 MA 0.15 PbI 0.85 Br 0.15 The perovskite light-absorbing material is spin-coated on the electron transport layer of Step 2 according to the classical one-step solution method. The first rotation speed is 1000 rpm for 10 s, the second stage rotation speed is 4000 rpm for 30 s. After 10 s of the second stage rotation speed, 800 μL of ethyl ether is taken and quickly dropped onto the perovskite light-absorbing layer, and then annealed at 140 °C for 10 min.

[0072] Step 4: Preparation of the strontium salt thin film layer: Take 200 μL of a strontium salt solution with a molar concentration of 1.0 mmol / L, spin-coat at 3000 rpm after standing for 15 s, and anneal at 110 °C for 10 min.

[0073] Step 5: Preparation of the hole transport layer: PTAA is spin-coated on the strontium salt thin film layer described in Step 4.

[0074] Step 6: Evaporate a gold electrode on the hole transport layer.

[0075] Example 5

[0076] Step 1: The same as Step 1 in Example 1.

[0077] Step 2: Preparation of the electron transport layer: SnO 2 solution (15% aqueous colloid dispersion and deionized water in a volume ratio of 1:6) is spin-coated on the FTO conductive glass and annealed at 140 °C for 30 min..

[0078] Step 3: Preparation of the perovskite light-absorbing layer: FA 0.85 MA 0.15 PbI 0.85 Br 0.15 The perovskite light-absorbing material is spin-coated on the electron transport layer of Step 2 according to the classical one-step solution method. The first rotation speed is 1000 rpm for 10 s, the second stage rotation speed is 4000 rpm for 30 s. After 10 s of the second stage rotation speed, 1000 μL of ethyl ether is taken and quickly dropped onto the above process, and then annealed at 145 °C for 15 min.

[0079] Step 4: Preparation of the strontium salt thin film layer: Take 200 μL of a strontium salt solution with a molar concentration of 1.5 mmol / L, spin-coat at 4000 rpm after standing for 10 s, and anneal at 115 °C for 10 min.

[0080] Step 5: Preparation of the hole transport layer: Spin-coat PTAA on the strontium salt thin film layer described in Step 4.

[0081] Step 6: Evaporate a gold electrode on the hole transport layer.

[0082] Detection examples

[0083] Fabricate test pieces A, B, C, and D respectively according to the following steps.

[0084] Test piece A

[0085] Step 1: Cleaning of FTO conductive glass: Ultrasonically clean with glass cleaner, acetone, isopropanol, absolute ethanol, and deionized water in sequence for 20 min, dry after cleaning, and remove surface impurities with a nitrogen gun.

[0086] Step 2: Preparation of the perovskite light-absorbing layer: Spin-coat the perovskite light-absorbing material of FA 0.85 MA 0.15 PbI 0.85 Br 0.15 onto the FTO conductive glass in Step 1 by the classic one-step solution method at a first rotation speed of 1000 rpm for 10 s, a second-stage rotation speed of 4000 rpm for 30 s, and quickly pipette 1000 μL of diethyl ether 10 s after the second-stage rotation speed and anneal at 150 °C for 15 min.

[0087] Test piece B

[0088] Step 1: The same as Step 1 of Test piece A.

[0089] Step 2: Preparation of the perovskite light-absorbing layer: Spin-coat the perovskite light-absorbing material of FA 0.85 MA 0.15 PbI 0.85 Br 0.15 onto the FTO conductive glass in Step 1 by the classic one-step solution method at a first rotation speed of 1000 rpm for 10 s, a second-stage rotation speed of 4000 rpm for 30 s, and quickly pipette 1000 μL of diethyl ether 10 s after the second-stage rotation speed and anneal at 150 °C for 15 min.

[0090] Step 3: Preparation of the strontium salt thin film layer: Take 500 μL of a strontium salt solution with a molar concentration of 1.0 mmol / L, spin-coat it on the perovskite light-absorbing layer in Step 2 at 4000 rpm after standing for 10 s, and anneal at 115 °C for 10 min.

[0091] The SEM images of Test piece A and Test piece B are respectively Figure 3 and Figure 4, it can be seen that the test piece B contains a strontium salt thin film layer with large grains on the surface, which can effectively reduce the surface area to volume ratio of the battery, form fewer defects at the grain boundaries, and thus reduce the occurrence of battery degradation.

[0092] The fluorescence emission diagrams of test piece A and test piece B are shown in Figure 5 , and it can be seen from the figure that the fluorescence intensity of test piece B is significantly higher than that of test piece A without the strontium salt thin film modification layer.

[0093] Figure 6 are the thin film fluorescence lifetime diagrams of test piece A and test piece B. It can be seen from the figure that the fluorescence lifetime of test piece A (~1428 ns) is much smaller than that of test piece B with the strontium salt modified layer thin film (~2939 ns), indicating that the defect states of the film with the strontium salt thin film modification layer are reduced, and the recombination of electrons and holes is reduced.

[0094] Test piece C

[0095] Step 1: The same as step 1 of test piece A.

[0096] Step 2: Preparation of the perovskite light-absorbing layer: Spin-coat the FA 0.95 MA 0.05 PbI 0.95 Br 0.05 perovskite light-absorbing material onto the FTO conductive glass in step 1 by the classic one-step solution method at a first rotation speed of 1000 rpm for 10 s, a second stage rotation speed of 4000 rpm for 30 s, and quickly add 1000 uL of diethyl ether 10 s after the second stage rotation speed, and anneal at 145 °C for 10 min.

[0097] Test piece D

[0098] Step 1: The same as step 1 of test piece A.

[0099] Step 2: Preparation of the perovskite light-absorbing layer: Spin-coat the FA 0.95 MA 0.05 PbI 0.95 Br 0.05 perovskite light-absorbing material onto the FTO conductive glass in step 1 by the classic one-step solution method at a first rotation speed of 1000 rpm for 10 s, a second stage rotation speed of 4000 rpm for 30 s, and quickly add 1000 uL of diethyl ether 10 s after the second stage rotation speed, and anneal at 145 °C for 10 min.

[0100] Step 3: Preparation of the strontium salt thin film layer: Take 500 uL of a strontium salt solution with a molar concentration of 1.0 mmol / L, spin-coat it onto the perovskite light-absorbing layer in step 2 at 4000 rpm after standing for 10 s, and anneal at 115 °C for 10 min.

[0101] Figure 7 XRD patterns of the films of Test Piece C and Test Piece D;

[0102] As Figure 7 shown, the two main diffraction peaks in the XRD pattern are located at about 14.3° and 28.4° respectively. For Test Piece D with the strontium salt thin film modification layer, the heights of both peaks have increased, and the full width at half maximum (FWHM) is smaller than that of Test Piece C without the strontium salt thin film modification layer, which confirms that the perovskite grain size and crystal quality have been improved after the strontium salt thin film modification layer.

[0103] Figure 8 UV absorption diagrams of the films of Test Piece C and Test Piece D;

[0104] As Figure 8 shown, the absorption edge of Test Piece D with the strontium salt thin film modification layer is 778 nm, which is about 3 nm longer than that of Test Piece C without the strontium salt thin film modification layer, indicating that it has a stronger absorption ability after containing the strontium salt thin film modification layer.

[0105] Figure 9 XPS energy spectra of I in the films of Test Piece C and Test Piece D;

[0106] Figure 10 XPS energy spectra of Pb in the films of Test Piece C and Test Piece D.

[0107] As Figure 9 and Figure 10 shown, the number 1 in the figure represents Test Piece C without the strontium salt thin film modification layer, and the number 2 represents the one with the strontium salt thin film modification layer. The XPS binding energies of Pb and I shift towards lower energy after the strontium salt thin film modification layer, which proves that after containing the strontium salt thin film modification layer, Cl in the strontium salt has a stronger interaction between Pb / I.

[0108] The above are the preferred embodiments of the present invention. All changes made according to the technical solution of the present invention, when the functions and effects generated do not exceed the scope of the technical solution of the present invention, shall fall within the protection scope of the present invention.

Claims

1. A high photoelectric conversion rate perovskite battery, characterized in that: The structure of the perovskite battery is, from bottom to top, an FTO conductive glass layer, an electron transport layer, a perovskite light absorption layer, a strontium chloride film layer, a hole transport layer and a gold electrode layer; the material of the electron transport layer is titanium dioxide or tin dioxide.

2. The high photoelectric conversion rate perovskite cell according to claim 1, characterized in that: The perovskite light absorbing layer material is FA x MA 1-x PbI x Br 1-x , where 0≤x≤1.

3. The high photoelectric conversion rate perovskite cell according to claim 1, characterized in that: The hole transport layer material is poly[bis(4-phenyl)(2,4,6-trimethylphenyl)amine] or 2,2,7,7-tetrakis[N,N-di(4-methoxyphenyl)amino]-9,9-spirobifluorene.

4. The method for preparing the high photoelectric conversion rate perovskite cell according to claim 1 comprises the following specific steps: Step 1, cleaning the FTO conductive glass: using glass cleaning agent, acetone, isopropanol, anhydrous ethanol, and deionized water ultrasonic cleaning FTO conductive glass respectively, and after drying, using a nitrogen gun to remove impurities on the surface of the FTO conductive glass; Step 2, preparing the electron transport layer: spin coating the electron transport layer material on the FTO conductive glass and annealing it; Step 3, prepare the perovskite light absorbing layer: prepare the perovskite light absorbing material into a solution according to the one-step solution method, and spin-coat the perovskite light absorbing material on the electron transport layer, the first speed is 1000 rpm, the time is 10s, the second stage speed is 4000 rpm, the time is 30s, after the second stage speed is 10s, the ether is quickly added to the perovskite light absorbing layer and annealed, the perovskite light absorbing material is FA x MA 1-x PbI x Br 1-x , where 0≤x≤1; Step 4, preparing a strontium salt thin film layer: spin coating a strontium salt solution on the perovskite light absorbing layer and performing an annealing treatment, wherein the strontium salt solution is a strontium chloride solution; Step 5, preparing a hole transport layer: spin coating a hole transport material on the strontium salt thin film layer, wherein the hole transport material is poly[bis(4-phenyl)(2,4,6-trimethylphenyl)amine] or 2,2,7,7-tetrakis[N,N-di(4-methoxyphenyl)amino]-9,9-spirobifluorene; Step 6: evaporate a gold electrode on the hole transport layer.

5. The method for preparing a perovskite cell with high photoelectric conversion efficiency according to claim 4, characterized in that: The electron transport layer material in step 2 is a titanium dioxide solution, which is prepared by diisopropyl dititanate and anhydrous n-butanol in a volume ratio of 1:(10-20), the annealing temperature is 450-500° C., and the annealing time is 60-90 min.

6. The method for preparing a perovskite cell with high photoelectric conversion efficiency according to claim 4, characterized in that: The electron transport layer material in step 2 is a tin dioxide hydrocolloid solution, which is prepared by mixing 15% hydrocolloid dispersion and deionized water in a volume ratio of 1:(4-10), with an annealing temperature of 140-150° C. and an annealing time of 30-40 min.

7. The method for preparing a perovskite cell with high photoelectric conversion efficiency according to claim 4, characterized in that: The molar concentration of the strontium chloride solution in step 4 is 0.5-2.0 mmoL / L.

8. The method for preparing a perovskite cell with high photoelectric conversion efficiency according to claim 4, characterized in that: When the strontium salt solution is spin-coated on the perovskite light-absorbing layer in step 4, the strontium salt solution is first allowed to stand for 10 to 15 seconds, the rotation speed during spin coating is 3000 to 5000 rpm, the annealing temperature is 110 to 115° C., and the annealing time is 5 to 10 minutes.

Images