CN108321296A - Trans- low-dimensional perovskite solar cell based on photon crystal heterojunction and preparation method thereof - Google Patents

Abstract

The invention relates to the technical field of solar cells, and discloses a trans-type low-dimensional perovskite solar cell based on a photonic crystal heterojunction and a preparation method thereof, including a transparent conductive substrate and hollow cells sequentially stacked on the transparent conductive substrate. Hole transport layer, low-dimensional perovskite light absorbing layer based on silica-titania photonic crystal heterojunction, hole blocking layer and metal electrode. Compared with the prior art, the trans low-dimensional perovskite solar cell based on photonic crystal heterojunction in the present invention has stronger slow light effect, higher capture efficiency of incident light, and higher carrier transport efficiency. High, good stability.

Description

Trans-type low-dimensional perovskite solar cells based on photonic crystal heterojunction and its preparation method

technical field

The invention relates to the technical field of solar cells, in particular to a trans-type low-dimensional perovskite solar cell based on a photonic crystal heterojunction and a preparation method thereof.

Background technique

With the increasing global energy crisis, solar energy has become a research hotspot in the field of renewable clean energy due to its advantages of abundant resources, wide distribution, and environmental protection. Perovskite solar cells (PSCs) have the characteristics of high photoelectric conversion efficiency, low cost, and simple process. As one of the most promising photovoltaic power generation technologies, they have received extensive attention.

Generally, PSCs have three typical structures, which are formal mesoporous structure (conducting glass (FTO)/electron transport layer/mesoporous layer/perovskite light absorption layer/hole transport layer/metal electrode), formal planar structure ( FTO/electron transport layer/perovskite light absorption layer/hole transport layer/metal electrode) and trans planar structure (FTO/hole transport layer/perovskite light absorption layer/electron transport layer/metal electrode). Researchers have conducted a lot of in-depth research on various components and interfaces in the device structure, such as: developing new inorganic hole transport materials, perovskite light absorbing layer materials, electron transport materials and metal electrode materials, optimizing hole transport layer/light absorbing layer and electron transport layer/light absorbing layer interface. In particular, the perovskite light-absorbing layer is the most critical component in the device structure, and its crystal structure, morphology and optical properties all play a vital role in device efficiency. In order to further improve the device efficiency, the researchers used bandgap engineering and interface engineering to explore the influence of the energy bandgap and interface matching of the perovskite light absorbing layer on the photoelectric performance of the device, and initially explained its internal mechanism. Especially in trans-PSCs, the use of bandgap engineering is beneficial to obtain a highly crystalline perovskite light-absorbing layer; the use of interface engineering can effectively optimize the battery device with better photoelectric performance. It can be seen that the trans planar structure is more conducive to the construction of PSCs with high device efficiency, small hysteresis effect and good stability. However, traditional three-dimensional perovskite materials also expose their own defects, especially the stability of temperature, humidity, and light and heat, which seriously hinders the large-scale application of PSCs. At the same time, low-dimensional perovskite materials exhibit better stability than three-dimensional perovskite materials due to their high formation energy, low self-doping effect, and low ion mobility. At present, the photoelectric conversion efficiency of low-dimensional perovskite solar cells has increased from 4.37% to 13.7%. However, how to obtain low-dimensional PSCs with excellent optoelectronic properties and low cost is still a difficult problem faced by academic and industrial circles.

Contents of the invention

Purpose of the invention: Aiming at the problems existing in the prior art, the present invention provides a trans-type low-dimensional perovskite solar cell based on photonic crystal heterojunction and its preparation method. The incident light capture efficiency is high, the carrier transport efficiency is high, and the stability is good.

Technical solution: The present invention provides a trans-type low-dimensional perovskite solar cell based on a photonic crystal heterojunction, which is characterized in that it includes a transparent conductive substrate and a hole transport layer sequentially stacked on the transparent conductive substrate , Low-dimensional perovskite light-absorbing layers, hole-blocking layers, and metal electrodes based on silica-titania photonic crystal heterojunctions.

Further, the low-dimensional perovskite light-absorbing layer is a silicon dioxide-titanium dioxide photonic crystal heterojunction filled with low-dimensional perovskite light-absorbing semiconductor materials. The construction of the heterojunction is conducive to improving the capture efficiency of the perovskite light-absorbing layer for incident light, and by adjusting its interface and thickness, a high-efficiency perovskite solar cell can be optimized; based on silica-titania photonic crystal heterogeneity The low-dimensional perovskite light-absorbing layer of the junction uses its photonic band gap and slow light effect to improve the quantum efficiency of the device, and uses the three-dimensional ordered macropore structure to improve the carrier transmission efficiency, thereby improving the photoelectric conversion efficiency of the device.

Preferably, the low-dimensional perovskite light-absorbing semiconductor material is a semiconductor material with an Aʹ ₂ A _n-1 B _n X _3n+1 type crystal structure, wherein the Aʹ is an organic amine ion, and the A is a cation , the B is a metal cation, the X is a halide anion, and the n is the number of layers of the low-dimensional perovskite.

Preferably, the organic amine ion is any one of the following: phenethylamine ion (PEA ⁺ ), n-butylamine ion (n-BA ⁺ ), isobutylamine ion (iso-BA ⁺ ), polyethyleneiminium ion (PEI ⁺ ); the cation is any one or combination of the following: methylamine cation (MA ⁺ , CH ₃ NH ₃ ⁺ ), formamidine cation (FA ⁺ , CH(NH ₂ ) ₂ ⁺ ), cesium ion ( Cs ⁺ ); the metal cation is any one or a combination of the following: Pb ²⁺ , Sn ²⁺ ; the halogen anion is any one or a combination of the following: I ^- , Br ^- , Cl ^- ; the n It is a natural number greater than 0 and less than or equal to 10.

Preferably, the hole transport layer is nickel oxide, copper oxide or cobalt oxide.

Preferably, the hole blocking layer is 2,9-dimethyl-4,7-biphenyl-1,10-phenanthroline (BCP).

Preferably, the metal electrode is a silver electrode or a gold electrode.

Preferably, the transparent conductive substrate is fluorine-doped tin oxide conductive glass (FTO).

The present invention also provides a method for preparing a trans-type low-dimensional perovskite solar cell based on a photonic crystal heterojunction, comprising the following steps: S1: preparing a hole transport layer on a transparent conductive substrate; S2: preparing a carbon dioxide Silicon precursor solution and titanium dioxide precursor solution; S3: Polystyrene pellets are used as building blocks, and the silicon dioxide precursor solution is configured to form an assembly solution A, and the transparent conductive substrate is used as a substrate. The constant temperature vertical deposition method deposits polystyrene-silica colloidal crystals on the hole transport layer; S4: use polystyrene beads as building blocks, and configure the assembly solution B with the titanium dioxide precursor solution, and The transparent conductive substrate is a substrate, and titanium dioxide is introduced on the polystyrene-silica colloidal crystal by a constant temperature vertical deposition method to obtain a polystyrene-silica-titania colloidal crystal heterojunction; S5: remove The polystyrene pellets in the polystyrene-silicon dioxide-titania colloidal crystal heterojunction obtain a three-dimensional ordered macroporous silica-titania photonic crystal heterojunction; S6: use the transparent conductive substrate As a substrate, a low-dimensional perovskite light-absorbing semiconductor material is filled in the three-dimensional ordered macroporous silica-titania photonic crystal heterojunction by a one-step method to obtain a silicon dioxide-titania photonic crystal heterojunction A low-dimensional perovskite light-absorbing layer; S7: sequentially vacuum-evaporating a hole blocking layer and a metal electrode on the low-dimensional perovskite light-absorbing layer.

Further, in the above S6, the one-step method specifically includes the following steps: First, prepare the precursor solution: weigh a certain amount of organic amine ions, cations, and metal cations and disperse them in N,N-dimethylformamide and di In methyl sulfoxide solvent, wherein, the molar concentration of metal cation is 0.6~1.2 mol/L, the volume ratio of N,N-dimethylformamide and dimethyl sulfoxide is 2:1 to 4:1; secondly, In the air environment, spin-coat the precursor solution on the silicon dioxide-titania photonic crystal heterojunction in turn: in the air environment, place the silicon dioxide-titania photonic crystal heterojunction substrate on the spin coating heat treatment at 75-95°C in the instrument, and then spin-coat the precursor solution at 70-80°C on the surface; finally, the low-dimensional perovskite light-absorbing layer is obtained after heat treatment: the DMF The crystallization dish covers the substrate, and the temperature is kept at 80-110° C. for 10-30 minutes to obtain a low-dimensional perovskite light-absorbing layer based on the heterojunction of silicon dioxide-titania photonic crystal.

Beneficial effects: the structure of the trans low-dimensional perovskite solar cell based on photonic crystal heterojunction in the present invention is conductive glass/hole transport layer/low-dimensional perovskite based on silicon dioxide-titania photonic crystal heterojunction Mineral light absorbing layer/hole blocking layer/metal electrode, its characteristics are:

1) Utilizing the photonic bandgap of the low-dimensional perovskite light-absorbing layer based on titanium dioxide photonic crystals improves the quantum efficiency of the device in the long wavelength range of 600-800nm;

2) Utilizing the match between the photonic bandgap of the low-dimensional perovskite light-absorbing layer based on silica photonic crystals and the energy bandgap of the perovskite material, the slow light effect is enhanced and the device’s capture efficiency of incident light is improved;

3) The low-dimensional perovskite light-absorbing layer based on silica-titania photonic crystal heterojunction has unique electrical properties: on the one hand, the low-dimensional perovskite light-absorbing layer based on silica photonic crystal can transfer the hole transport layer It is separated from the low-dimensional perovskite light-absorbing layer based on titanium dioxide photonic crystals to avoid the recombination of electrons in titanium dioxide and holes in the hole transport layer; on the other hand, electrons can be transported to the hole blocking layer through titanium dioxide, and then pass through The hole blocking layer enters the metal electrode, and at the same time, the hole blocking layer can block holes from entering the metal electrode, avoiding the recombination of electrons and holes at the metal electrode; it can be seen that the low-dimensional calcium based on silica-titania photonic crystal heterojunction The above-mentioned unique electrical properties of the titanium ore light-absorbing layer help to improve the transport efficiency of carriers;

4) Using the ordered macroporous structure of the low-dimensional perovskite light-absorbing layer based on the silica-titania photonic crystal heterojunction can effectively improve the carrier transport efficiency;

5) Trans-type low-dimensional perovskite solar cell devices based on photonic crystal heterojunctions exhibit certain colors and enhance the aesthetics.

6) The trans-type low-dimensional perovskite solar cell based on photonic crystal heterojunction in the present invention can effectively prepare a battery device with large area and excellent performance. Compared with the three-dimensional perovskite solar cell, it has small hysteresis effect and stable Good sex and other advantages.

Description of drawings

Figure 1 is a schematic diagram of the structure of a trans-type low-dimensional perovskite solar cell based on a photonic crystal heterojunction;

Figure 2 is a flow chart of the preparation of trans-type low-dimensional perovskite solar cells based on photonic crystal heterojunction;

Fig. 3 is the preparation flowchart of polystyrene-silica colloidal crystal;

Fig. 4 is the preparation flowchart of three-dimensional ordered macroporous silica-titania photonic crystal heterojunction;

Fig. 5 is a flowchart of the preparation of a low-dimensional perovskite light-absorbing layer based on a silica-titania photonic crystal heterojunction.

The present invention will be described in detail below in conjunction with the accompanying drawings.

Implementation mode 1:

This embodiment provides a trans-type low-dimensional perovskite solar cell based on a photonic crystal heterojunction. The structure is shown in FIG. Silicon oxide-titania photonic crystal heterojunction low-dimensional perovskite light-absorbing layer, BCP hole blocking layer and silver electrode composition. The low-dimensional perovskite light-absorbing layer is a three-dimensional ordered macroporous silica-titania photonic crystal heterojunction filled with (PEA) ₂ (FA) ₈ Sn ₉ I ₂₈ .

The preparation method of the above-mentioned trans-type low-dimensional perovskite solar cell based on photonic crystal heterojunction is as follows, and the preparation flow chart is shown in Figure 2:

S1: Preparation of nickel oxide hole transport layer on FTO by spin coating method;

The specific process is: use absolute ethanol as a solvent to prepare a nickel acetylacetonate solution with a concentration of 0.5 mol/L, and add diethanolamine equal to the molar number of nickel ions, and stir at 70°C for 12 hours; after the reaction is completed, the solution is Evaporate at 150°C for 30 minutes to form a nickel oxide precursor; place the cleaned FTO conductive glass on a spin coater, drop in the nickel oxide precursor, and spin coat at 3000 rpm for 30 seconds; The FTO is placed in a drying oven and dried at 60° C. for 1 hour to obtain a nickel oxide hole transport layer.

S2: preparing a silicon dioxide precursor solution and a titanium dioxide precursor solution;

The specific process of preparing the silica precursor solution is as follows: firstly, at room temperature, mix and stir 1mL tetraethyl orthosilicate and 1mL absolute ethanol; secondly, slowly add 0.25mL hydrochloric acid and 0.2 mL of deionized water to obtain a silica precursor solution; finally, store the prepared silica precursor solution at 4°C for future use.

The specific process of configuring the titanium dioxide precursor solution is as follows: firstly, at room temperature, mix 1mL tetra-n-butyl titanate and 1mL absolute ethanol and stir evenly; secondly, under stirring conditions, slowly add 0.2mL hydrochloric acid and 0.4mL to ionized water to obtain a titanium dioxide precursor solution; finally, store the prepared titanium dioxide precursor solution at 4°C for future use.

S3: Polystyrene pellets were used as building blocks, and the silicon dioxide precursor solution prepared in S2 was configured to form assembly solution A. The FTO prepared in S1 and spin-coated with a nickel oxide hole transport layer was used as the substrate. Deposit polystyrene-silica colloidal crystals on nickel oxide by constant temperature vertical deposition method;

The specific process is: using monodisperse polystyrene beads prepared by soap-free emulsion polymerization as the building block, dispersing 0.1 mL of the silica precursor solution in 50 mL of polystyrene beads with a mass fraction of 0.05% in ethanol solution , configured as assembly solution A, and placed in a vacuum drying oven at a temperature of 25°C; insert the FTO substrate spin-coated with nickel oxide into assembly solution A, and after the solvent evaporates, polystyrene- Silica colloidal crystals; the preparation flow chart is shown in Figure 3.

S4: Polystyrene pellets are used as the building block, and the titanium dioxide precursor solution prepared in S2 is configured to form assembly solution B, and FTO with polystyrene-silica colloidal crystals deposited on nickel oxide is used as the substrate. Introduce titanium dioxide on polystyrene-silica colloidal crystals by constant temperature vertical deposition method to obtain polystyrene-silica-titania colloidal crystal heterojunction;

The specific process is: using monodisperse polystyrene beads prepared by soap-free emulsion polymerization as building blocks, dispersing 0.1 mL of titanium dioxide precursor solution in 50 mL of polystyrene beads ethanol solution with a mass fraction of 0.05%, and configuring Assemble solution B, and place it in a vacuum oven at a temperature of 25°C; insert the FTO substrate with polystyrene-silica colloidal crystals deposited on nickel oxide into assembly solution B, and after the solvent evaporates, The polystyrene-silicon dioxide-titanium dioxide colloidal crystal heterojunction can be prepared.

S5: removing the polystyrene balls in the polystyrene-silica-titania colloidal crystal heterojunction in S4 to obtain a three-dimensional ordered macroporous silica-titania photonic crystal heterojunction;

The specific process is as follows: the polystyrene-silica-titanium dioxide colloidal crystal heterojunction is placed in a sintering furnace for heat treatment, the heating rate is 2°C per minute, and it is kept at 500°C for 1 hour to obtain a three-dimensional ordered large Porous silica-titania photonic crystal heterojunction; the two-step preparation flow chart of S4 and S5 is shown in Figure 4.

S6: Using FTO with a three-dimensional ordered macroporous silica-titania photonic crystal heterojunction as a substrate, the three-dimensional ordered macroporous silica-titania photonic crystal heterojunction is filled with (PEA) ₂ in one step (FA) ₈ Sn ₉ I ₂₈ , to obtain a low-dimensional perovskite light-absorbing layer based on silica-titania photonic crystal heterojunction;

First, prepare the precursor solution. The specific process is: weigh 0.13mmol of phenethylammonium iodide (PEAI), 0.60mmol of tin iodide (SnI ₂ ), 0.53mmol of formamidine ammonium iodide (FAI), 0.06mmol of tin fluoride (SnF ₂ ) Disperse in 1 mL of solvent (0.67 mL of N,N-dimethylformamide and 0.33 mL of dimethyl sulfoxide), stir at 70°C for 3 hours to form a precursor solution;

Secondly, in an air environment, the precursor solution is sequentially spin-coated on the silicon dioxide-titania photonic crystal heterojunction. The specific process is as follows: in the air environment, the FTO substrate with a three-dimensional ordered macroporous silica-titania photonic crystal heterojunction is placed in a spin coater and heat-treated at 75 ° C for 15 minutes, and then the three-dimensional organic Spin-coating a precursor solution at a temperature of 70°C on the surface of the sequenced macroporous silica-titania photonic crystal heterojunction, and the spin-coating condition is to spin-coat for 30 seconds under the condition of 5000 revolutions/second;

Finally, the low-dimensional perovskite light-absorbing layer is obtained through heat treatment. The specific process is: cover the substrate with a DMF-attached crystallization dish, and continue the treatment at 80°C for 30 minutes to obtain a low-dimensional perovskite light-absorbing layer based on the heterojunction of silicon dioxide-titanium dioxide photonic crystals. The preparation process is shown in Figure 5.

S7: On the low-dimensional perovskite light-absorbing layer, a hole-blocking layer and a metal electrode were sequentially vacuum-evaporated to obtain a trans-type low-dimensional perovskite solar cell based on a photonic crystal heterojunction.

The specific process is as follows: the above-mentioned FTO substrate with a low-dimensional perovskite light-absorbing layer is placed in a high-vacuum coating device, and BCP and silver electrodes are evaporated in sequence to construct a trans low-dimensional perovskite based on a photonic crystal heterojunction. mine solar cell, and control the area of the device to 0.1cm ² through the mask plate.

Implementation mode 2:

This embodiment provides a trans-type low-dimensional perovskite solar cell based on a photonic crystal heterojunction. The structure is shown in FIG. Silicon oxide-titania photonic crystal heterojunction low-dimensional perovskite light absorbing layer, BCP hole blocking layer and gold electrode composition. The low-dimensional perovskite light-absorbing layer is a three-dimensional ordered macroporous silica-titania photonic crystal heterojunction filled with (BA) ₂ (MA) ₃ Pb ₄ I ₁₃ ,

The preparation method of the above-mentioned trans-type low-dimensional perovskite solar cell based on photonic crystal heterojunction is as follows, and the preparation flow chart is shown in Figure 2:

S1: Preparation of copper oxide hole transport layer on FTO by spin coating method;

The specific process is: use ethylene glycol as a solvent to configure a copper sulfate pentahydrate solution with a concentration of 0.5 mol/L, and add a certain amount of 1,2-ethylenediamine dihydrochloride (with a concentration of 1.0 mol/L); to be reacted After the end, the copper oxide precursor can be formed; put the cleaned FTO conductive glass on the spin coater, drop the copper oxide precursor, and spin coat at 6000 rpm for 50 seconds; put the FTO in the tube furnace In the process, heat treatment at 300° C. for 2 hours under an argon atmosphere can obtain a copper oxide hole transport layer.

S2: preparing a silicon dioxide precursor solution and a titanium dioxide precursor solution;

The specific process of preparing the silica precursor solution is as follows: firstly, at room temperature, mix and stir 1mL tetraethyl orthosilicate and 1mL absolute ethanol; secondly, slowly add 0.25mL hydrochloric acid and 0.2 mL of deionized water to obtain a silica precursor solution; finally, store the prepared silica precursor solution at 4°C for future use.

The specific process of configuring the titanium dioxide precursor solution is as follows: firstly, at room temperature, mix 1mL tetra-n-butyl titanate and 1mL absolute ethanol and stir evenly; secondly, under stirring conditions, slowly add 0.2mL hydrochloric acid and 0.4mL to ionized water to obtain a titanium dioxide precursor solution; finally, store the prepared titanium dioxide precursor solution at 4°C for future use.

S3: Polystyrene pellets were used as the building block, and the silicon dioxide precursor solution prepared in S2 was configured to form assembly solution A, and the FTO prepared in S1 was spin-coated with a copper oxide hole transport layer as the substrate. Deposit polystyrene-silica colloidal crystals on copper oxide by constant temperature vertical deposition method;

The specific process is: using monodisperse polystyrene beads prepared by soap-free emulsion polymerization as the building block, dispersing 0.1 mL of the silica precursor solution in 50 mL of polystyrene beads with a mass fraction of 0.05% in ethanol solution , configured as assembly solution A, and placed in a vacuum oven at a temperature of 25°C; insert the FTO substrate spin-coated with copper oxide into assembly solution A, and after the solvent evaporates, polystyrene- Silica colloidal crystals; the preparation flow chart is shown in Figure 3.

S4: Polystyrene pellets are used as the building block, and the titanium dioxide precursor solution prepared in S2 is configured to form assembly solution B, and FTO with polystyrene-silica colloidal crystals deposited on copper oxide is used as the substrate. Introduce titanium dioxide on polystyrene-silica colloidal crystals by constant temperature vertical deposition method to obtain polystyrene-silica-titania colloidal crystal heterojunction;

The specific process is: using monodisperse polystyrene beads prepared by soap-free emulsion polymerization as building blocks, dispersing 0.1 mL of titanium dioxide precursor solution in 50 mL of polystyrene beads ethanol solution with a mass fraction of 0.05%, and configuring Assemble solution B, and place it in a vacuum drying oven at a temperature of 25°C; insert the FTO substrate with polystyrene-silica colloidal crystals deposited on copper oxide into assembly solution B, and after the solvent evaporates, The polystyrene-silicon dioxide-titanium dioxide colloidal crystal heterojunction can be prepared.

S5: removing the polystyrene balls in the polystyrene-silica-titania colloidal crystal heterojunction in S4 to obtain a three-dimensional ordered macroporous silica-titania photonic crystal heterojunction;

The specific process is as follows: the polystyrene-silica-titania colloidal crystal heterojunction is placed in a sintering furnace for heat treatment, the heating rate is 2°C per minute, and it is kept at 450°C for 1 hour to obtain a three-dimensional ordered large Porous silica-titania photonic crystal heterojunction; the two-step preparation flow chart of S4 and S5 is shown in Figure 4.

S6: Using FTO with a three-dimensional ordered macroporous silica-titania photonic crystal heterojunction as a substrate, the three-dimensional ordered macroporous silica-titania photonic crystal heterojunction is filled with (BA) ₂ in one step (MA) ₃ Pb ₄ I ₁₃ , to obtain a low-dimensional perovskite light-absorbing layer based on silica-titania photonic crystal heterojunction;

First, prepare the precursor solution. The specific process is: weigh 0.45 mmol of butyl ammonium iodide (BAI), 0.675 mmol of methyl ammonium iodide (MAI), and 0.90 mmol of lead iodide (PbI ₂ ) and disperse them in 1 mL of solvent (0.75 mL of N , N-dimethylformamide and 0.25mL of dimethyl sulfoxide), stirred at 70°C for 3 hours to form a precursor solution;

Secondly, in an air environment, the precursor solution is sequentially spin-coated on the above-mentioned silica-titania photonic crystal heterojunction. The specific process is as follows: in the air environment, the FTO substrate with a three-dimensional ordered macroporous silica-titania photonic crystal heterojunction is placed in a spin coater and heat-treated at 85°C for 15 minutes, and then the three-dimensional organic Spin-coating a precursor solution at a temperature of 75° C. on the surface of a sequenced macroporous silica-titania photonic crystal heterojunction, and the spin-coating condition is to spin-coat at 5000 rpm for 20 seconds;

Finally, the low-dimensional perovskite light-absorbing layer is obtained through heat treatment. The specific process is as follows: cover the substrate with a DMF-attached crystal dish, and continue the treatment at 95°C for 20 minutes to obtain a low-dimensional perovskite light-absorbing layer based on the heterojunction of silicon dioxide-titanium dioxide photonic crystals. The preparation process is shown in Figure 5.

S7: On the low-dimensional perovskite light-absorbing layer, a hole-blocking layer and a metal electrode were sequentially vacuum-evaporated to obtain a trans-type low-dimensional perovskite solar cell based on a photonic crystal heterojunction.

The specific process is as follows: the above-mentioned FTO substrate with a low-dimensional perovskite light-absorbing layer is placed in a high-vacuum coating device, and BCP and gold electrodes are sequentially evaporated to construct a trans low-dimensional perovskite based on a photonic crystal heterojunction. mine solar cell, and control the area of the device to 0.1cm ² through the mask plate.

Implementation mode 3:

This embodiment provides a trans low-dimensional perovskite solar cell based on a photonic crystal heterojunction. The structure is shown in FIG. Silicon oxide-titania photonic crystal heterojunction low-dimensional perovskite light absorbing layer, BCP hole blocking layer and gold electrode composition. The low-dimensional perovskite light-absorbing layer is a three-dimensional ordered macroporous silica-titania photonic crystal heterojunction filled with (PEI) ₂ (MA) ₂ Sn ₃ I ₁₀ ,

The preparation method of the above-mentioned trans-type low-dimensional perovskite solar cell based on photonic crystal heterojunction is as follows, and the preparation flow chart is shown in Figure 2:

S1: Preparation of cobalt oxide hole transport layer on FTO by spin coating method;

The specific process is: use ethylene glycol as a solvent to prepare a cobalt acetate tetrahydrate solution with a concentration of 0.5 mol/L, and add a certain amount of 1,2-ethylenediamine dihydrochloride (with a concentration of 1.0 mol/L); After the end, the cobalt oxide precursor can be formed; put the cleaned FTO conductive glass on the spin coater, drop the cobalt oxide precursor, and spin coat at 6000 rpm for 50 seconds; put the FTO in the tube furnace , heat treatment at 300° C. for 2 hours under an argon atmosphere to obtain a cobalt oxide hole transport layer.

S2: preparing a silicon dioxide precursor solution and a titanium dioxide precursor solution;

The specific process of preparing the silica precursor solution is as follows: firstly, at room temperature, mix and stir 1mL tetraethyl orthosilicate and 1mL absolute ethanol; secondly, slowly add 0.25mL hydrochloric acid and 0.2 mL of deionized water to obtain a silica precursor solution; finally, store the prepared silica precursor solution at 4°C for future use.

The specific process of configuring the titanium dioxide precursor solution is as follows: firstly, at room temperature, mix 1mL tetra-n-butyl titanate and 1mL absolute ethanol and stir evenly; secondly, under stirring conditions, slowly add 0.2mL hydrochloric acid and 0.4mL to ionized water to obtain a titanium dioxide precursor solution; finally, store the prepared titanium dioxide precursor solution at 4°C for future use.

S3: Polystyrene pellets were used as building blocks, and the silicon dioxide precursor solution prepared in S2 was configured to form assembly solution A, and the FTO prepared in S1 with a spin-coated cobalt oxide hole transport layer was used as a substrate. Deposit polystyrene-silica colloidal crystals on cobalt oxide by constant temperature vertical deposition method;

The specific process is: using monodisperse polystyrene beads prepared by soap-free emulsion polymerization as the building block, dispersing 0.1 mL of the silica precursor solution in 50 mL of polystyrene beads with a mass fraction of 0.05% in ethanol solution , configured as assembly solution A, and placed in a vacuum oven at a temperature of 25°C; insert the FTO substrate spin-coated with cobalt oxide into assembly solution A, and after the solvent evaporates, polystyrene- Silica colloidal crystals; the preparation flow chart is shown in Figure 3.

S4: Polystyrene pellets are used as the building block, and the titanium dioxide precursor solution prepared in S2 is configured to form assembly solution B, and FTO with polystyrene-silica colloidal crystals deposited on cobalt oxide is used as the substrate. Introduce titanium dioxide on polystyrene-silica colloidal crystals by constant temperature vertical deposition method to obtain polystyrene-silica-titania colloidal crystal heterojunction;

The specific process is: using monodisperse polystyrene beads prepared by soap-free emulsion polymerization as building blocks, dispersing 0.1 mL of titanium dioxide precursor solution in 50 mL of polystyrene beads ethanol solution with a mass fraction of 0.05%, and configuring Assemble solution B, and place it in a vacuum drying oven at a temperature of 25°C; insert the FTO substrate with polystyrene-silica colloidal crystals deposited on cobalt oxide into assembly solution B, and after the solvent evaporates, The polystyrene-silicon dioxide-titanium dioxide colloidal crystal heterojunction can be prepared.

S5: removing the polystyrene balls in the polystyrene-silica-titania colloidal crystal heterojunction in S4 to obtain a three-dimensional ordered macroporous silica-titania photonic crystal heterojunction;

The specific process is as follows: the polystyrene-silica-titania colloidal crystal heterojunction is placed in a sintering furnace for heat treatment, the heating rate is 2°C per minute, and it is kept at 450°C for 1 hour to obtain a three-dimensional ordered large Porous silica-titania photonic crystal heterojunction; the two-step preparation flow chart of S4 and S5 is shown in Figure 4.

S6: Using FTO with a three-dimensional ordered macroporous silica-titania photonic crystal heterojunction as a substrate, a two-step method is used to fill (PEI) the three-dimensional ordered macroporous silica-titania photonic crystal heterojunction ₂ (MA) ₂ Pb ₃ I ₁₀ , to obtain a low-dimensional perovskite light-absorbing layer based on silica-titania photonic crystal heterojunction;

First, prepare the precursor solution. The specific process is: weigh 0.80 mmol of polyethyleneimine hydroiodide (PEI HI), 0.80 mmol of methylamine iodide (MAI), and 1.20 mmol of lead iodide (PbI ₂ ) and disperse them in 1 mL of solvent (0.8mL of N,N-dimethylformamide and 0.2mL of dimethyl sulfoxide), stirred at 70°C for 3 hours to form a precursor solution;

Secondly, in an air environment, the precursor solution is sequentially spin-coated on the above-mentioned silica-titania photonic crystal heterojunction. The specific process is as follows: in the air environment, the FTO substrate with a three-dimensional ordered macroporous silica-titania photonic crystal heterojunction is placed in a spin coater and heat-treated at 95 ° C for 15 minutes, and then the three-dimensional organic Spin-coating a precursor solution at a temperature of 80° C. on the surface of a sequenced macroporous silica-titania photonic crystal heterojunction, and the spin-coating condition is 30 seconds at 3000 rpm;

Finally, the low-dimensional perovskite light-absorbing layer is obtained through heat treatment. The specific process is: cover the substrate with a DMF-attached crystal dish, and continue the treatment at 110°C for 10 minutes to obtain a low-dimensional perovskite light-absorbing layer based on the heterojunction of silicon dioxide-titanium dioxide photonic crystals. The preparation process is shown in Figure 5.

S7: On the three-dimensional perovskite light-absorbing layer, a hole-blocking layer and a metal electrode were sequentially vacuum-evaporated to obtain a reverse three-dimensional perovskite solar cell based on a photonic crystal heterojunction.

The specific process is as follows: the above-mentioned FTO substrate with a three-dimensional perovskite light-absorbing layer is placed in a high-vacuum coating device, and BCP and gold electrodes are evaporated in sequence to construct a trans-three-dimensional perovskite solar energy based on a photonic crystal heterojunction. battery, and control the area of the device to 0.1cm ² through the mask plate.

The above-mentioned embodiments are only for illustrating the technical concept and characteristics of the present invention, and its purpose is to enable those skilled in the art to understand the content of the present invention and implement it accordingly, and not to limit the scope of protection of the present invention. All equivalent changes or modifications made according to the spirit of the present invention shall fall within the protection scope of the present invention.

Claims (9)

1. A trans-type low-dimensional perovskite solar cell based on a photonic crystal heterojunction, characterized in that it comprises a transparent conductive substrate and a hole transport layer stacked on the transparent conductive substrate in sequence, based on silicon dioxide - Low-dimensional perovskite light-absorbing layers, hole-blocking layers, and metal electrodes for titanium dioxide photonic crystal heterojunctions. 2. The trans low-dimensional perovskite solar cell based on photonic crystal heterojunction according to claim 1, wherein the low-dimensional perovskite light-absorbing layer is filled with low-dimensional perovskite light-absorbing semiconductors Materials for silica-titania photonic crystal heterojunctions. 3. The trans low-dimensional perovskite solar cell based on photonic crystal heterojunction according to claim 2, characterized in that, the low-dimensional perovskite light-absorbing semiconductor material has Aʹ ₂ A _n-1 B A semiconductor material with _n X _3n+1 crystal structure, wherein the Aʹ is an organic amine ion, the A is a cation, the B is a metal cation, the X is a halogen anion, and the n is a low-dimensional perovskite layers of mine. 4. The trans low-dimensional perovskite solar cell based on photonic crystal heterojunction according to claim 3, characterized in that, The organic amine ion is any one of the following: phenylethylamine ion (PEA ⁺ ), n-butylamine ion (n-BA ⁺ ), isobutylamine ion (iso-BA ⁺ ), polyethyleneiminium ion (PEI ⁺ ); The cation is any one of the following or a combination thereof: methylamine cation, formamidine cation, cesium ion; The metal cation is any one or combination of the following: Pb ²⁺ , Sn ²⁺ ; The halogen anion is any one or combination of the following: I ^- , Br ^- , Cl ^- ; The n is a natural number greater than 0 and less than or equal to 10. 5. The trans-type low-dimensional perovskite solar cell based on photonic crystal heterojunction according to any one of claims 1 to 4, wherein the hole transport layer is nickel oxide, copper oxide or oxide cobalt. 6. The trans-type low-dimensional perovskite solar cell based on photonic crystal heterojunction according to any one of claims 1 to 4, wherein the hole blocking layer is 2,9-dimethyl -4,7-biphenyl-1,10-phenanthroline. 7. The trans low-dimensional perovskite solar cell based on photonic crystal heterojunction according to any one of claims 1 to 4, wherein the metal electrode is a silver electrode or a gold electrode. 8. The trans low-dimensional perovskite solar cell based on photonic crystal heterojunction according to any one of claims 1 to 4, wherein the transparent conductive substrate is fluorine-doped tin oxide conductive glass . 9. The preparation method of the trans-type low-dimensional perovskite solar cell based on photonic crystal heterojunction according to any one of claims 1 to 8, characterized in that, comprising the following steps: S1: preparing a hole transport layer on a transparent conductive substrate; S2: preparing a silicon dioxide precursor solution and a titanium dioxide precursor solution; S3: Polystyrene beads are used as building blocks, and the silicon dioxide precursor solution is configured to form an assembly solution A, and the transparent conductive substrate is used as a substrate, and the constant temperature vertical deposition method is used to transport holes in the Polystyrene-silica colloidal crystals are deposited on the layer; S4: Polystyrene pellets are used as building blocks, and the titanium dioxide precursor solution is configured to form an assembly solution B, and the transparent conductive substrate is used as a substrate, and the constant temperature vertical deposition method is used on the polystyrene-II Titanium dioxide is introduced into the silica colloidal crystal to obtain polystyrene-silica-titania colloidal crystal heterojunction; S5: removing the polystyrene pellets in the polystyrene-silicon dioxide-titania colloidal crystal heterojunction to obtain a three-dimensional ordered macroporous silica-titania photonic crystal heterojunction; S6: Using the transparent conductive substrate as the substrate, a one-step method is used to fill the three-dimensional ordered macroporous silica-titania photonic crystal heterojunction with a low-dimensional perovskite-based light-absorbing semiconductor material to obtain a Low-dimensional perovskite light-absorbing layer of silicon-titania photonic crystal heterojunction; S7: Vacuum-evaporating a hole blocking layer and a metal electrode sequentially on the low-dimensional perovskite light-absorbing layer.