CN111146300B - Addition of CsPbBr based on amine Compounds3Inorganic perovskite solar cell and preparation method and application thereof - Google Patents

Abstract

The invention provides an inorganic perovskite solar cell based on amine compound adding CsPbBr ₃ and its preparation method and application. The invention specifically prepares an electron transport layer on FTO conductive glass, and then spin-coats the surface of the brominated amine compound added Lead solution, spin-coating cesium bromide solution several times to obtain high-quality perovskite thin films, and finally scrape-coating carbon slurry as the back electrode to assemble an inorganic perovskite solar cell. In the present invention, by adding an amine compound to the lead bromide solution, the crystallization and growth rate of _CsPbBr crystal grains are delayed, and a perovskite film with large grain size and dense and uniform is obtained. In addition, the amine compound can effectively passivate the perovskite Defects on the surface and inside of the mineral thin film, and improve the energy level matching of the battery interface, thereby inhibiting charge recombination and improving the photovoltaic performance of the battery. The invention has the advantages of simple and easy preparation method, low cost, high repeatability, outstanding stability under high temperature and high humidity environment, and the like.

Description

Inorganic perovskite solar cells based on amine compound adding CsPbBr3 and their preparation methods and applications

technical field

The invention belongs to the fields of new material technology and new energy technology, and particularly relates to an inorganic perovskite solar cell based on amine compound adding CsPbBr ₃ in additive engineering and its application as a cell component.

Background technique

At present, the photoelectric conversion efficiency of organic-inorganic hybrid perovskite solar cells has reached 25.2%. Perovskite may replace crystalline silicon and become the "new favorite" of solar cells. However, there are still many problems. For example, the hybrid perovskite solar cell contains expensive organic components, and its long-term stability is poor in high temperature and high humidity environment, which seriously affects its commercialization process. Hole-free, carbon-based _CsPbBr3 all-inorganic perovskites prepared by replacing organic ions with inorganic cesium ions are characterized by their simple preparation process, low cost, and an optimal balance between efficiency and long-term operational stability. It has become a research hotspot in the field of photovoltaics.

The nucleation and growth rate of _CsPbBr3 grains prepared by the traditional multi-step liquid phase heating method is too fast, which is not conducive to the full formation of perovskite crystals, and the defect state density inside and on the surface of the film is high, resulting in serious charge Recombination, which limits the improvement of the photoelectric conversion efficiency of the battery. Based on the above two problems, it is of great theoretical significance and practicality to find an additive that can not only affect the crystallization kinetics of perovskite crystals, but also passivate film defects at the same time. The preparation of high-performance inorganic perovskite solar cells based on additive engineering value.

SUMMARY OF THE INVENTION

The purpose of the present invention is to provide an inorganic perovskite solar cell based on amine compound adding CsPbBr ₃ and its preparation method and application. The present invention can obtain simple preparation method, low cost, outstanding quality of perovskite film, excellent photovoltaic performance and Inorganic perovskite solar cells with long-term operational stability have important practical significance and economic value to accelerate the commercial application of perovskite solar cells.

In order to realize the above-mentioned purpose of the invention, the present invention adopts the following technical solutions to be realized:

The invention provides a preparation method of an inorganic perovskite solar cell based on an amine compound adding CsPbBr ₃ , which comprises the following steps:

(1) Various solutions required for preparation: isopropyl titanate ethanol solution with a concentration of 0.1-1 mol/L, titanium dioxide slurry with a concentration of 0.05-0.1 g/mL, and a concentration of 0.01-0.05 mol/L Titanium tetrachloride aqueous solution; added cesium bromide methanol solution with a concentration of 1-2 mol/L lead bromide DMF solution (0.5-5%) and a concentration of 0.05-0.1 mol/L of amine compounds in different molar ratios;

(2), the ethanol solution of above-mentioned prepared isopropyl titanate is spin-coated on the etched and cleaned FTO substrate at a speed of 7000 rpm for 30 seconds, and then high-temperature calcination makes a dense titanium dioxide layer;

(3), spin-coating the dense titanium dioxide layer obtained in step (2) at a speed of 2000 rpm with the prepared titanium dioxide slurry for 30 seconds, and then calcining at high temperature to obtain a titanium dioxide film;

(4), soaking the titanium dioxide film prepared in step (3) in the prepared titanium tetrachloride solution, after heating and soaking in a water bath, cleaning with water and absolute ethanol in turn, and then calcining at high temperature to obtain mesoporous titanium dioxide film;

(5), the lead bromide DMF solution of adding different proportions of amine compounds prepared above is spin-coated on the film surface prepared by step (4), then heated;

(6), spin coating the cesium bromide methanol solution prepared above on the surface of the lead bromide film prepared in step (5), heat at high temperature, and repeat this step many times to prepare high-quality CsPbBr _perovskite light-absorbing Floor;

(7), the surface of the CsPbBr ₃ perovskite light-absorbing layer prepared in step (6) is scraped with carbon slurry to assemble a high-performance CsPbBr ₃ all-inorganic perovskite solar cell based on amine compounds as perovskite precursor solution additives .

Further: the molar ratio in the step (1) is the molar ratio of the amine compound and the lead ion in the lead bromide DMF solution, and after the lead bromide in the DMF solution is completely dissolved, the amine compound is added to dissolve the solution to prepare a solution.

Further: in the step (2), the FTO glass is etched with zinc powder and hydrochloric acid, and ultrasonically cleaned with deionized water, ethanol and acetone in sequence for 3-4 times.

Further: in the step (3), the mesoporous titanium dioxide film is prepared by calcining at 400-500 degrees in a muffle furnace.

Further: in the step (4), the 60-80 degree water bath is heated for 20-40 minutes, and the mesoporous titanium dioxide film is prepared by calcination in a muffle furnace at 400-500 degree.

Further: in the step (5), the specific conditions for spin-coating and adding lead bromide DMF solutions of different proportions of amine compounds are that the rotating speed is 2500 rpm and the time is 30 seconds.

Further: in the step (6), the spin coating times of cesium bromide are 6 to 8 times, the rotation speed is 2500 rpm, and the time is 30 seconds.

The present invention also provides the inorganic perovskite solar cell based on amine compound adding CsPbBr ₃ .

Further: the open circuit voltage of the inorganic perovskite solar cell is 1.4-1.6V, the short-circuit current is 5.8-7.5 mA·cm ^-2 , the filling factor is 0.68-0.80, and the photoelectric conversion efficiency is 6-10%.

The invention also provides the application of the inorganic perovskite solar cell based on amine compound adding CsPbBr ₃ as a cell component.

Compared with the prior art, the advantages and technical effects of the present invention are:

1. The present invention makes full use of the amino group of the amine compound, and its nitrogen atom with a lone electron pair can be combined with the lead ion in the PbBr ₂ solution, thereby effectively reducing the nodule and growth rate of the CsPbBr ₃ crystal, making the perovskite The ore grains are fully formed, and a film with a large grain size is obtained; and the amino group can obviously passivate the positively charged ion defects existing in the film and on the surface, reducing the non-radiative recombination path of carriers, and to a large extent. On the other hand, the charge recombination existing inside and on the surface of the perovskite film is inhibited, and the efficiency of the _CsPbBr3 inorganic perovskite solar cell is increased to more than 9%.

2. The amine compound added in the present invention itself has hydrophobicity. It is found that the CsPbBr _{3 film added with the amine compound (taking melamine as an example) has a higher contact angle and stronger hydrophobicity than the pure CsPbBr 3 film} . The prepared battery is more stable under high temperature and high humidity environment, and is not easy to degrade. The optimized inorganic perovskite solar cells operated continuously for 30 days in an air environment with a humidity of 85% and a temperature of 85°, respectively, without significant degradation in photovoltaic performance.

3. The CsPbBr3 _perovskite is prepared by adding an amine compound in the present invention, which effectively improves the energy level matching between the light absorption layer and the charge transfer layer of the perovskite, reduces the interface energy loss of the solar cell device and the photo-generated electron-hole recombination, and promotes the battery Improvement of photovoltaic performance. At the same time, compared with interface engineering (another passivation defect, reducing charge recombination), the additive engineering does not need to increase the preparation process and introduce a new interface, which avoids the formation of energy level differences between the interfaces and the unnecessary increase of interface resistance. Charge recombination, this invention is simple and feasible.

Description of drawings

Fig. 1 is the JV curve of the inorganic perovskite solar cell prepared by the present invention based on an amine compound (taking melamine as an example) adding CsPbBr ₃ .

Figure 2 is the contact angle of the inorganic perovskite thin film prepared by the present invention based on amine compound (taking melamine as an example) adding CsPbBr ₃ .

Figure 3 shows the stability of the inorganic perovskite solar cells based on amine compounds (taking melamine as an example) added with CsPbBr ₃ prepared by the present invention: a, high temperature 85°C; b, humidity 85°, temperature 20°C.

Detailed ways

The technical solutions of the present invention will be described in further detail below in conjunction with specific embodiments.

Example 1

The preparation method of the inorganic perovskite solar cell based on amine compound adding CsPbBr ₃ according to the present invention comprises the following steps:

1. Prepare isopropyl titanate ethanol solution with a concentration of 0.5mol/L (isopropyl titanate is the solute and ethanol is the solvent), and prepare 0.1 g/mL TiO ₂ slurry (TiO ₂ is a solute, deionized water is a solvent), prepare a titanium tetrachloride solution with a concentration of 0.04 mol/L (titanium tetrachloride is a solute, and deionized water is a solvent), and respectively prepare and add 0.5-5% melamine in a molar ratio The 1mol/L lead bromide DMF solution (lead bromide, amine compound are solute, DMF is solvent), preparation concentration is the cesium bromide solution of 0.07mol/L (cesium bromide is solute, methanol is solvent);

2. Spin-coat 90 μL of the isopropyl titanate ethanol solution on the FTO conductive glass substrate for 30 seconds at a rotational speed of 7000 rpm, and then calcine at 550 degrees for 2 hours to obtain a dense layer of titanium dioxide;

3. Spin-coat the dense layer of the titanium dioxide slurry prepared in step 1 on step 2 for 30 seconds, at a rotational speed of 3000 rpm, and then calcine at 450 degrees for 30 minutes;

4. Soak the film prepared in step 3 in the titanium tetrachloride solution for 30 minutes, the heating temperature of the water bath is 75 degrees, and then calcined at 450 degrees for 30 minutes to prepare the mesoporous titanium dioxide film;

5. The lead bromide DMF solution (0.5-5%) prepared in step 1 with different molar ratios of melamine added was spin-coated on the surface of the titanium dioxide film prepared in step 4 for 30 seconds at a rotational speed of 2500 rpm, and then at 90 The titanium dioxide/lead bromide film was prepared by heating for 30 minutes at 100 degrees Celsius;

6. Spin-coating the cesium bromide solution prepared in step 1 on the surface of the film prepared in step 5 for 30 seconds at a rotational speed of 2500 rpm, and then heat at 250 degrees for 8 minutes;

7. Repeat the spin coating process in step 6 for 7 times to prepare CsPbBr ₃ perovskite light-absorbing layers added with different molar ratios of melamine;

8. Scratch carbon slurry on the surface of the CsPbBr3 _perovskite light-absorbing layer prepared in step 7, then heat it at 90 degrees for 20 minutes to dry, and assemble into a high-performance CsPbBr3 based on melamine as the _perovskite precursor solution additive prepared Inorganic perovskite solar cells.

The performance test results of the inorganic perovskite solar cell are shown in FIG. 1 , FIG. 2 and FIG. 3 . Through the above-mentioned method, an amine compound-added inorganic CsPbBr ₃ -based inorganic compound with an open-circuit voltage of 1.4-1.6 V, a short-circuit current of 5.8-7.5 mA·cm ^-2 , a fill factor of 0.68-0.80, and a photoelectric conversion efficiency of 6-10% was obtained. Perovskite solar cells.

The above embodiments are only used to illustrate the technical solutions of the present invention, but not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art can still The recorded technical solutions are modified, or some technical features thereof are equivalently replaced; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions claimed in the present invention.

Claims (8)

1. the preparation method of the inorganic perovskite solar cell based on amine compound adding CsPbBr ₃ , is characterized in that, comprises the following steps: (1) Various solutions required for preparation: isopropyl titanate ethanol solution with a concentration of 0.1-1 mol/L, titanium dioxide slurry with a concentration of 0.05-0.1 g/mL, and a concentration of 0.01-0.05 mol/L Titanium tetrachloride aqueous solution, adding a 0.5-5% molar ratio of an amine compound with a concentration of 1-2 mol/L lead bromide DMF solution, and a cesium bromide methanol solution with a concentration of 0.05-0.1 mol/L; The molar ratio is the molar ratio of the amine compound and the lead ion in the lead bromide DMF solution. After the lead bromide in the DMF solution is completely dissolved, the solution is prepared by adding an amine compound to dissolve, and the added amine compound is cyanamide, and two Polycyanamide, melamine, ethanolamine, diethanolamine, triethanolamine, twelve to nineteen amines, etc.; (2), the ethanolic solution of above-mentioned prepared isopropyl titanate is spin-coated for 30 seconds on the etched and cleaned FTO substrate at a speed of 7000 rev/min, and then high-temperature calcination makes a dense titanium dioxide layer; (3), spin-coating the above-mentioned prepared titanium dioxide slurry on the dense titanium dioxide layer obtained in step (2) at a speed of 2000 rpm for 30 seconds, and then calcining at high temperature to obtain a titanium dioxide film; (4), soaking the titanium dioxide film prepared in step (3) in the prepared titanium tetrachloride solution, after heating and soaking in a water bath, cleaning with water and absolute ethanol in turn, and then calcining at high temperature to obtain mesoporous titanium dioxide film; (5), the lead bromide DMF solution of adding different proportions of amine compounds prepared above is spin-coated on the film surface prepared by step (4), then heated; (6), spin coating the cesium bromide methanol solution prepared above on the surface of the lead bromide film prepared in step (5), heat at high temperature, and repeat this step many times to prepare high-quality CsPbBr _perovskite light-absorbing Floor; (7), coating the surface of the CsPbBr ₃ perovskite light-absorbing layer prepared in step (6) with carbon slurry, and assembling an inorganic perovskite solar cell based on an amine compound adding CsPbBr ₃ . 2 . The method for preparing an inorganic perovskite solar cell based on an amine compound adding CsPbBr ₃ according to claim 1 , wherein in the step (3), the preparation medium is prepared by calcining in a muffle furnace at 400-500 degrees. 3 . Porous titanium dioxide films. 3. The preparation method of an inorganic perovskite solar cell based on an amine compound adding CsPbBr ₃ according to claim 1, characterized in that: in the step (4), 60-80 degree water bath heating for 20-40 minutes, in horse The mesoporous titanium dioxide film is prepared by calcining at 400-500 degrees in a Furnace. 4. the preparation method of the inorganic perovskite solar cell based on amine compound adding CsPbBr ₃ according to claim 1, is characterized in that: in described step (5), spin coating adds the lead bromide DMF solution of amine compound in different proportions The specific conditions are that the speed is 2500 rpm and the time is 30 seconds. 5. The method for preparing an inorganic perovskite solar cell based on an amine compound adding CsPbBr ₃ according to claim 1, wherein the spin coating times of cesium bromide in the step (6) are 6 to 8 times, Speed 2500 rpm, time 30 seconds. 6 . The inorganic perovskite solar cell based on amine compound adding CsPbBr ₃ prepared by the preparation method according to any one of claims 1 to 5. 7. The inorganic perovskite solar cell based on amine compound adding CsPbBr ₃ according to claim 6, wherein the CsPbBr ₃ inorganic perovskite solar cell has an open circuit voltage of 1.4-1.6V and a short-circuit current of 5.8 ~7.5 mA·cm ⁻² , fill factor of 0.68 to 0.80, and photoelectric conversion efficiency of 6 to 10%. 8. The application of the inorganic perovskite solar cell based on amine compound adding CsPbBr ₃ as claimed in claim 6 as a cell component.

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