CN110246966A - A kind of novel ferroelectric photovoltaic material and its application - Google Patents

Abstract

The invention discloses preparation methods of two novel ferroelectric photovoltaic materials and ferroelectric photovoltaic devices prepared by using the materials. The ferroelectric photovoltaic material is ABC _4‑4x D _4x , 0≤x≤1. A is an organic cation, B is a metal cation, and C and D are inorganic anions. By adjusting the type materials of A, B, C and D, ferroelectric photovoltaic materials can be obtained. Among them, (C ₆ H ₁₁ NH ₂ ) ₂ PbBr ₄ and (C ₆ H ₁₁ NH ₂ ) ₂ PbI ₄ exhibited excellent ferroelectric photovoltaic properties. It exhibits good ferroelectric photovoltaic performance. The present invention also discloses two ferroelectric thin film photovoltaic devices based on this material. One is a traditional sandwich model with electrodes at the upper and lower ends; the other is a transverse sandwich model with electrodes at the left and right ends. The upper electrode (or any end electrode of the lateral electrode) is a transparent electrode material such as indium tin oxide (ITO), and the lower electrode (or any end electrode of the lateral electrode) is a metal with low work function such as Au, Ag, Al, Mg.

Description

A Novel Ferroelectric Photovoltaic Material and Its Application

technical field

The invention relates to a ferroelectric photovoltaic material, in particular to a novel ferroelectric photovoltaic material and application thereof, and belongs to the technical field of ferroelectric photovoltaic materials.

Background technique

Ferroelectric photovoltaic material refers to any material with dual characteristics of ferroelectric effect and photovoltaic effect. The ferroelectric effect refers to the property of spontaneous electric polarization in the state where no external electric field is applied. Experiments have found that such materials have the characteristic of ferroelectricity, which overcomes the fact that traditional photovoltaic materials must have PN junctions, and theoretically can achieve infinite ferroelectric photovoltaics. Traditional silicon-based photovoltaic materials often use a layer of P-type material and a layer of N-type material stacked on each other to generate a PN junction in the production process to achieve photovoltaic effect, and the photoelectric conversion rate is low. Ferroelectric photovoltaic materials overcome this point. Due to the existence of spontaneous polarization, all ferroelectric materials themselves can be considered as PN junctions, which greatly improves the photoelectric conversion efficiency. Therefore, the use of ferroelectric photovoltaic materials can completely replace the original silicon-based photovoltaic materials, and the economic benefit is much higher than that of silicon-based photovoltaic materials.

ABC _4-4x D _4x material is a new type of ferroelectric photovoltaic material, which has the characteristics of multipolar axis and high polarization voltage, and its own residual polarization is large. beyond traditional silicon-based optoelectronic materials. However, the existing technologies generally have problems such as low utilization efficiency and complicated preparation methods, which limit the application of photovoltaic materials to a certain extent. Most ferroelectric materials have wide band gaps. When used as semiconductor materials, their ability to absorb light is extremely weak. Usually, only photogenerated electron-hole pairs can be generated under ultraviolet light irradiation. At the same time, the conductivity is very poor. low, it is difficult to meet the needs of the application. Therefore, how to improve the photoelectric conversion efficiency and make ferroelectrics practical as photovoltaic materials has become a new technical problem.

SUMMARY OF THE INVENTION

The present invention is aimed at the problems existing in the prior art, provides a novel ferroelectric photovoltaic material, a preparation method and application thereof, and provides two photovoltaic structures, which can maximize the utilization efficiency of the ferroelectric photovoltaic material, The preparation method is simple and the application is wide.

In order to achieve the above object, the technical scheme of the present invention is as follows, a novel ferroelectric photovoltaic material, characterized in that the ferroelectric photovoltaic material has the general formula: ABC _4-4x D _4x . Wherein: A is nitrogen-containing or containing Phosphorus organic cation, B is a metal cation, C and D are inorganic anions.

As an improvement of the present invention, the A is a nitrogen-containing or phosphorus-containing organic cation, specifically including tetramethylamine cation, tetramethylphosphine cation, trimethylchloromethylamine cation, trimethylfluoromethylamine cation cation, trimethylbromomethylamine cation, trimethyliodomethylamine cation, trimethyldifluoromethylamine cation, trimethyltrifluoromethylamine cation, trimethylhydroxylamine cation, trimethylethylamine cation base cation, trimethylpropyl cation, trimethylchloroethyl cation, trimethylamine cation, triethylamine cation, tetraethylamine cation, triethylamine methyl cation, triethylamine chloromethyl cation, triethylamine Fluoromethyl cation, triethylamine bromomethyl cation, triethylamine iodomethyl cation, pyrrolidine cation, pyrroline cation, quinuclidine cation, imidazolium cation, pyridinium cation, aminopyrrolidine cation, aminoquinuclidine cation , one or more of piperazine cations or triethylenediamine cations.

As an improvement of the present invention, B is a metal cation, specifically including ^: Cd ²⁺ , Mn ²⁺ , Cu ²⁺ , Zn ²⁺ , Ni ²⁺ , Co ²⁺ , Fe ²⁺ , Cr ²⁺ , V ^{2 +} , Hg ²⁺ , Cu ⁺ , Ag ⁺ , Au ⁺ , Al ³⁺ , In ²⁺ , Sn ²⁺ , Pb ²⁺ , Sb ³⁺ , Bi ³⁺ , Na ⁺ , K ⁺ , Rb ⁺ , Cs ⁺ One or more of , Mg ²⁺ , Ca ²⁺ , Sr ²⁺ or Ba ²⁺ .

As an improvement of the present invention, C and D are inorganic anions, and the anions include: one of Cl ^- , Br ^- , I ^- , SCN ^- , N ^3- , ClO ^4- , CN ^- or BF ^4- or several.

A method for synthesizing the novel ferroelectric photovoltaic material, characterized in that the preparation method utilizes a solution method to synthesize, that is, a class A organic amine salt or phosphine salt and BC _1-x D _x (0≤x≤ 1) metal salt, the amount of substance is respectively 20mmol, 10mmol, mix in 100 milliliters of water, DMF, hydrochloric acid, hydrobromic acid or hydroiodic acid solvent to obtain clear solution, heat under 353K temperature, by slow cooling, cooling rate is 0.2K·h ^-1 , crystals are obtained, and the target sample is obtained.

A method for preparing a ferroelectric photovoltaic thin film using the novel ferroelectric photovoltaic material, characterized in that the method comprises the following steps;

Step 1: prepare a precursor solution by dissolving the ferroelectric photovoltaic material in a solvent;

Step 2: Clean the substrate;

Step 3: take the precursor solution, take 20 microliters of solution each time, and use the drop coating method or spin coating method to make it evenly cover the surface of the substrate;

Step 4: remove the solvent by room temperature volatilization or thermal annealing to obtain a thin film;

Step 5: removing the substrate by chemical method or physical method to obtain a ferroelectric photovoltaic thin film.

Step 6: Ferroelectric polarization is performed on the obtained ferroelectric photovoltaic thin film.

As an improvement of the present invention, the solvent in step 1 includes water, methanol, DMF, ethanol, acetone, petroleum ether, diethyl ether, chloroform, trichloroethylene, formamide, ethylene glycol, methylacetamide, Aminoethanol, acetic acid, propanol, butanol, DMSO, acetonitrile, aniline, ethylenediamine, morpholine, pyridine, THF, quinine, toluene and other organic solvents; the ratio is: 300mg/ml.

The substrate in step 4 includes Si, SiO ₂ , polymer film, quartz or conductive glass;

The polarization process described in step 6 is carried out under the conditions of the phase transition temperature and the polarization voltage slightly greater than that of the polarization, and the photoelectric test is carried out. An application of a new type of ferroelectric photovoltaic material, characterized in that the ferroelectric photovoltaic material is used in photovoltaic devices and photovoltaic cells, and the photovoltaic device includes an upper electrode, a metal lower electrode or lateral left and right electrodes, and an electrode located between the two electrodes. A thin film of ferroelectric photovoltaic material between the two electrodes; either end electrodes of the upper electrode or lateral electrodes are transparent electrode materials such as indium tin oxide (ITO); any end electrodes of the metal lower electrodes or lateral electrodes are Au, Ag, Al, Mg metals with low work function.

Compared with the prior art, the present invention has the following advantages. The two ferroelectric photovoltaic cells designed by this technical solution are characterized by a novel ferroelectric photovoltaic material in the middle. The present invention also discloses two ferroelectric thin film photovoltaic devices based on this material. . One is a traditional sandwich model with electrodes at the upper and lower ends; the other is a transverse sandwich model with electrodes at the left and right ends. The upper electrode (or any end electrode of the lateral electrode) is a transparent electrode material such as indium tin oxide (ITO), and the lower electrode (or any end electrode of the lateral electrode) is a metal with low work function such as Au, Ag, Al, and Mg. The purpose is to improve the open circuit voltage and other characteristics of photovoltaic cells and broaden the application range of ferroelectric devices. The device is characterized by the use of a new type of ferroelectric material in the central photoelectric layer. The material we have obtained (C ₆ H ₁₁ NH ₂ ) _{2 PbBr 4-4x} I _4x has good ferroelectric and optoelectronic properties. Generally speaking, the contact between strong bonds makes the energy gap between HOMO and LUMO larger. The bond between Pb atom and Br atom is weaker, and the bond between Pb and I atom is weaker, so the energy band of this material is lower than that of general materials, thereby reducing the turn-on voltage of the device. Energy bands were measured by UV-Vis spectroscopy. See Figure 3. As the Br content in the molecule decreases, the energy band also decreases gradually.

Description of drawings

Figure 1 shows the traditional sandwich element diagram of ABC _4-4x D _4x ferroelectric optoelectronic materials

Figure 2 is a diagram of a lateral sandwich element of ABC _4-4x D _4x ferroelectric optoelectronic materials.

Figure 3a is the UV-Vis spectrum for the composition of x=0, the inset is the Tauc plot; b is the normalized absorption spectrum for the composition of x=0, 0.175 and 1.

In the picture:

Detailed ways:

In order to deepen the understanding of the present invention, the present embodiment will be described in detail below with reference to the accompanying drawings.

Embodiment 1: A ferroelectric photovoltaic material having the general formula ABC _4-4x D _4x : wherein A is tetramethylamine cation, tetramethylphosphine cation, trimethylchloromethylamine cation, Trimethylfluoromethylamine cation, trimethylbromomethylamine cation, trimethyliodomethylamine cation, trimethyldifluoromethylamine cation, trimethyltrifluoromethylamine cation, trimethyl cation Hydroxylamine cation, trimethylethyl cation, trimethylpropyl cation, trimethylchloroethyl cation, trimethylamine cation, triethylamine cation, tetraethylamine cation, triethylamine methyl cation, triethylamine chloride Methyl cation, triethylamine fluoromethyl cation, triethylamine bromomethyl cation, triethylamidoiodomethyl cation, pyrrolidine cation, pyrroline cation, quinuclidine cation, imidazolium cation, pyridine cation, aminopyrrolidine cation, aminoquinuclidine cation, piperazine cation or triethylenediamine cation. B is metal cation, including: Cd2+, Mn2+, Cu2+, Zn2+, Ni2+, Co2+, Fe2+, Cr2+, V2+, Hg2+, Cu+, Ag+, Au+, Al3+, In2+, Sn2+, Pb2+, Sb3+, Bi3+, Na+, K+, Rb+, Cs+, Mg2+, Ca2+, Sr2+, Ba2+, etc.; C and D are anions, including: Cl ^- , Br ^- , I ^- , SCN ^- , N ^3- , ClO ^4- , CN ^- or BF ^4- . The optoelectronic materials are: aminoquinine·PbI ₄ , aminopyrrolidine·PbBr ₄ , cyclohexylamine·PbCl ₄ and the like.

Example 2:

When A=C ₆ H ₁₁ NH ₂ , B=Pb and C=D=I in the molecular-based binary ferroelectric photovoltaic material, the present invention provides a ferroelectric photovoltaic material (C ₆ H ₁₁ NH ₂ ) ₂ PbI _4. .

Methylamine, PbI ₂ and HI solutions are mixed in a certain stoichiometric ratio, heated, and cooled by reflux to obtain crystals, the molecular formula is (C ₆ H ₁₁ NH ₂ ) ₂ PbI ₄ .

Example 3:

When A=DFCHA, B=Pb, C=Br, D=I in the above molecular-based binary piezoelectric material, the present invention provides a ferroelectric optoelectronic material (C ₆ H ₁₁ NH) with excellent ferroelectric optoelectronic properties. ₂ ) 2PbBr4-4xI4x.

Mix C ₆ H ₁₁ NH ₂ , PbBr ₂ , HBr solution and HI solution in a certain stoichiometric ratio, heat, and slowly cool to obtain crystals, the molecular formula is (C ₆ H ₁₁ NH ₂ ) ₂ PbI ₄ .

Example 4:

The invention provides a preparation method of a ferroelectric photovoltaic thin film, and the specific steps are as follows:

Step 1: prepare a precursor solution by dissolving the ferroelectric photovoltaic material in a solvent;

Step 2: Clean the substrate;

Step 3: take the precursor liquid, and make it evenly cover the surface of the above-mentioned substrate by the drop coating method or the spin coating method;

Step 4: remove the solvent by room temperature volatilization or thermal annealing to obtain a thin film;

Step 5: removing the substrate by chemical method or physical method to obtain a ferroelectric photovoltaic thin film.

Step 6: Ferroelectric polarization is performed on the obtained ferroelectric photovoltaic thin film.

The solvent of step 1 includes water, methanol, DMF, ethanol, acetone, petroleum ether, diethyl ether, chloroform, trichloroethylene, formamide, ethylene glycol, methylacetamide, aminoethanol, acetic acid, propanol, butanol , DMSO, acetonitrile, aniline, ethylenediamine, morpholine, pyridine, THF, quinine, toluene and other organic solvents.

The sinking substrate described in step 4 includes but is not limited to Si, SiO ₂ , polymer film, quartz or conductive glass. The polarization process of step 6 is carried out under the condition of phase transition temperature and slightly larger than polarization voltage. And conduct photoelectric test.

Example 5:

The present invention designs two ferroelectric photovoltaic devices, one of which includes an upper electrode, a metal lower electrode, and a ferroelectric material film. The second consists of left and right electrodes and a thin film of ferroelectric photovoltaic material in the middle. The upper electrode (or any end electrode of the lateral electrode) is a transparent electrode material such as indium tin oxide (ITO), and the lower electrode (or any end electrode of the lateral electrode) is a metal with low work function such as Au, Ag, Al, Mg. Assemble by chemical and physical methods, and test the battery.

The two ferroelectric photovoltaic cells designed by the present invention are characterized by a novel ferroelectric photovoltaic material in the middle. The purpose is to improve the open circuit voltage and other characteristics of photovoltaic cells and broaden the application range of ferroelectric devices.

It should be noted that the above-mentioned embodiments are not intended to limit the protection scope of the present invention, and equivalent transformations or substitutions made on the basis of the above-mentioned technical solutions all fall into the protection scope of the present invention.

Claims (10)

1. a kind of novel ferroelectric photovoltaic material, which is characterized in that the ferroelectricity photovoltaic material has general formula are as follows: ABC_4-4xD_4xIts In: A is nitrogenous or phosphorous organic cation, and B is metal cation, and C and D are inorganic anion.

2. novel ferroelectric photovoltaic material according to claim 1, which is characterized in that the A is nitrogenous or phosphorous organic sun Ion specifically includes tetramethyl amine cation, tetramethyl phosphine cation, trimethyl chloromethyl base amine cation, trimethyl methyl fluoride Amine cation, trimethyl bromomethyl amine cation, trimethyl iodomethyl amine cation, trimethyl difluoromethyl amine cation, three Methyl trifluoro methyl amine cation, trimethyl azanol cation, trimethylethyl cation, thmethylpropyl cation, front three Base chloroethyl cation, front three amine cation, triethylamine cation, tetrem amine cation, triethylamine methyl-cation, triethylamine Chloromethyl cation, triethylamine methyl fluoride cation, triethylamine bromomethyl cation, triethylamine iodomethyl cation, pyrrolidines Cation, pyrroles's cation moiety, quinuclidine cation, glyoxaline cation, pyridylium, amino-pyrrolidine cation, amino One or more of quinuclidine cation, piperazine cation or triethylene diamine cation.

3. novel ferroelectric photovoltaic material according to claim 2, which is characterized in that B is metal cation, is specifically included: Cd²⁺、Mn²⁺、Cu²⁺、Zn²⁺、Ni²⁺、Co²⁺、Fe²⁺、Cr²⁺、V²⁺、Hg²⁺、Cu⁺、Ag⁺、Au⁺、Al³⁺、In²⁺、Sn²⁺、Pb²⁺、Sb³⁺、 Bi³⁺、Na⁺、K⁺、Rb⁺、Cs⁺、Mg²⁺、Ca²⁺、Sr²⁺Or Ba²⁺One of or it is several.

4. novel ferroelectric photovoltaic material according to claim 2, which is characterized in that C and D is inorganic anion, the yin Ion includes: Cl^-、Br^-、I^-、SCN^-、N^3-、ClO^4-、CN^-Or BF^4-One of or it is several.

5. novel ferroelectric photovoltaic material according to claim 4, which is characterized in that the ferroelectricity photovoltaic material is (C₆H₁₁NH₂)₂PbBr_4-4xI_4x。

6. the method for synthesizing novel ferroelectric photovoltaic material described in claim 1-4 any one, which is characterized in that the preparation side Method is synthesized using solwution method, that is, by A class organic amine salt or phosphonium salt and BC_1-xD_x(0≤x≤1) metal salt, water, DMF, It is mixed to get clear solution in hydrochloric acid, hydrobromic acid or hydroiodic acid solvent, heats, crystal is obtained by Slow cooling, obtains target Sample.

7. special using the method for the preparation ferroelectricity photovoltaic film of novel ferroelectric photovoltaic material described in claim 1-4 any one Sign is, the described method comprises the following steps；

Step 1: precursor liquid is prepared with solvent dissolved iron electricity photovoltaic material；

Step 2: substrate is cleaned up；

Step 3: taking the precursor liquid, using drop-coating or spin-coating method, make its uniform fold in above-mentioned substrate surface；

Step 4: solvent being removed by room temperature volatilization or heating anneal, obtains film；

Step 5: using the substrate is chemically or physically removed, obtaining ferroelectricity photovoltaic film.

Step 6: iron electric polarization is carried out to resulting ferroelectricity photovoltaic film.

8. the method for preparation ferroelectricity photovoltaic film according to claim 7, which is characterized in that

Solvent described in step 1 includes water, methanol, DMF, ethyl alcohol, acetone, petroleum ether, ether, chloroform, trichloro ethylene, first Amide, ethylene glycol, methylacetamide, ethylaminoethanol, acetic acid, propyl alcohol, butanol, DMSO, acetonitrile, aniline, ethylenediamine, morpholine, pyrrole The organic solvents such as pyridine, THF, quinine, toluene；

Substrate described in step 4 includes Si, SiO₂, macromolecule membrane, quartz or electro-conductive glass；

Polarization process described in step 6 is to carry out in phase transition temperature and slightly larger than polarizing voltage under conditions of, and carry out photoelectricity test.

9. the application of claim 1-4 any one novel ferroelectric photovoltaic material, which is characterized in that the ferroelectricity photovoltaic material is answered Used in photovoltaic device, the application of photovoltaic cell.

10. the application of novel ferroelectric photovoltaic material according to claim 9, which is characterized in that the photovoltaic device includes Top electrode, lower metal electrode or lateral left and right electrode and the ferroelectricity photovoltaic material film between two electrodes；It is described to power on Any end electrode of pole or transverse electrode is transparent electrode materials such as tin indium oxide (ITO)；The lower metal electrode or transverse direction The metal of the low work functions such as any end the electrode A u, Ag, Al, Mg of electrode.