阅读说明：本技术 一种以硒化铟与一价铜为中间体浸渍提拉工艺制备铜铟硒薄膜的方法 (Method for preparing copper indium selenide film by dipping and drawing process with indium selenide and monovalent copper as intermediates ) 是由 季惠明 黄雄 于 2019-03-15 设计创作，主要内容包括：本发明公开一种以硒化铟与一价铜为中间体浸渍提拉工艺制备铜铟硒薄膜的方法,采用热注射法制备In<Sub>2</Sub>Se<Sub>3</Sub>纳米墨水,以In<Sub>2</Sub>Se<Sub>3</Sub>作为支撑层,通过与Cu<Sup>+</Sup>溶液在室温下进行叠层,硒化退火后得到CIS薄膜。在此过程中,In<Sub>2</Sub>Se<Sub>3</Sub>纳米墨水与Cu<Sup>+</Sup>溶液反复交替提拉,In<Sub>2</Sub>Se<Sub>3</Sub>不仅提供In和Se源,同时起到支撑的作用,使预制层薄膜的厚度在10次循环后达到2μm。In<Sub>2</Sub>Se<Sub>3</Sub>纳米粒子表面能高,叠层后界面具有高能量,烧结中高的界面能成为原子运动的驱动力,有利于界面附近的原子扩散、空洞收缩,此外Cu<Sup>+</Sup>与Se蒸气反应得到低熔液相Cu-Se化合物,包裹In<Sub>2</Sub>Se<Sub>3</Sub>纳米粒子,有利于Cu与In相互扩散,从而得到致密的CIS薄膜。(The invention discloses a method for preparing a copper indium diselenide film by using an immersion and drawing process with indium selenide and monovalent copper as intermediates, which adopts a hot injection method to prepare In 2 Se 3 Nano ink of In 2 Se 3 As a support layer, by reacting with Cu + And (4) laminating the solution at room temperature, and selenizing and annealing to obtain the CIS film. In this process, In 2 Se 3 Nano ink and Cu + Repeatedly and alternately pulling In the solution 2 Se 3 Not only provides In and Se sources, but also plays a role of supporting, so that the thickness of the prefabricated layer film reaches 2 mu m after 10 cycles. In 2 Se 3 The surface energy of the nano particles is high, the interface has high energy after lamination, the high interface energy in sintering becomes the driving force of atom movement, the atom diffusion and the cavity shrinkage near the interface are facilitated, and in addition, the Cu + Reacting with Se vapor to obtain low-melting liquid phase Cu-Se compoundSubstance, encapsulating In 2 Se 3 The nano particles are beneficial to mutual diffusion of Cu and In, so that a compact CIS film is obtained.)

1. A method for preparing a copper indium selenide film by using an immersion and drawing process with indium selenide and monovalent copper as intermediates is characterized by comprising the following steps:

step 1, standing Mo glass in a manner of being vertical to indium selenide nano ink, then carrying out lifting and pulling, and repeating; standing the Mo glass in a monovalent copper solution perpendicularly, then pulling and repeating to obtain a CIS prefabricated layer;

and 2, placing the Mo glass plated with the CIS prefabricated layer obtained in the step 1 in a reaction container containing selenium powder, heating to 450-550 ℃ from room temperature of 20-25 ℃ at a heating rate of 5-10 ℃/min under an inert protective atmosphere, carrying out heat preservation reaction for 30-60 min, and cooling to room temperature along with a furnace to obtain the copper indium selenium film.

2. The method for preparing the copper indium diselenide thin film by the dipping and drawing process taking indium selenide and monovalent copper as intermediates, as claimed in claim 1, wherein in the step 1, a mixed solution of anhydrous ethanol and anhydrous ethylenediamine is used as a solvent, and the volume ratio of the two is (3-5): 1, adding CuCl powder into the mixed solution, and fully stirring to dissolve the CuCl powder to obtain Cu with the concentration of 0.12-0.18 mol/L⁺And (3) solution.

3. The method for preparing the copper indium diselenide thin film by using the immersion and drawing process with indium selenide and monovalent copper as intermediates as claimed in claim 1, wherein in step 1, Mo glass is pretreated, ultrasonically cleaned with isopropanol, distilled water and absolute ethyl alcohol for 30-40 min respectively, and dried in a clean environment for standby.

4. The method for preparing the copper indium diselenide thin film by using the immersion and drawing process with indium selenide and monovalent copper as intermediates as claimed in claim 1, wherein in the step 1, absolute ethyl alcohol is used as a dispersing solvent in the indium selenide nano ink, and the concentration is 0.075-0.125 mol/L.

5. The method for preparing the copper indium diselenide thin film by the dipping and drawing process taking indium selenide and monovalent copper as intermediates as claimed In claim 1, wherein In the step 1, Mo glass is perpendicular to In₂Se₃Standing the nano ink for 4-6 s, pulling out, and repeating the step for 1 time after the ethanol solvent on the Mo glass is completely volatilized; then, the Mo glass is vertical to the monovalent copper solution, and is lifted out after standing for 1-3 s so as to completely volatilize the solvent; the pulling coating is a cycle, and the CIS prefabricated layer is obtained by continuously operating 10-15 cycles.

6. The method for preparing a copper indium diselenide thin film by using an immersion and drawing process with indium selenide and monovalent copper as intermediates as claimed in claim 1, wherein in the step 2, the reaction vessel is a graphite crucible, and the temperature rise and holding reaction is carried out by using a tube furnace.

7. The method for preparing the copper indium diselenide thin film by the dip-coating process taking indium selenide and monovalent copper as intermediates as claimed in claim 1, wherein in the step 2, the inert protective atmosphere is nitrogen, helium or argon.

8. The method for preparing the copper indium diselenide thin film by using the immersion and drawing process with indium selenide and monovalent copper as intermediates as claimed in claim 1, wherein in the step 2, the temperature is raised to 480-520 ℃ at a temperature raising speed of 8-10 ℃/min, and the temperature is kept for reaction for 30-40 min.

9. Use of a copper indium diselenide thin film prepared according to the method of any one of claims 1 to 8 for the preparation of a copper indium diselenide thin film based solar cell.

10. The use according to claim 9, wherein the forbidden band width is 1.04-1.05 eV and the hole concentration is (2.20-2.41) × 10¹⁶cm^-3The electric mobility is 7.23-7.61 cm²V^-1S^-1The resistivity is 53.2 to 61.3 Ω · cm.

Technical Field

The invention belongs to the field of solar cells, namely a method for preparing CuInSe₂A method for forming a photoanode absorption layer, In₂Se₃Preparing nano ink and monovalent copper ethanol solution, namely preparing CuInSe through selenylation annealing after obtaining a precursor by using a dipping and pulling method₂A method of making a thin film.

Background

Photovoltaic materials, as the name implies, a material that directly converts solar energy into electrical energy, it provides a continuous and viable approach to meet the growing energy needs of mankind, due to the high visible light absorption coefficient of copper indium selenide-based thin film solar cells (3-6 × 10)⁵cm^-1) (ii) a The preparation cost is low, and the silicon solar cell is only 1/3-1/2 of a silicon solar cell; the forbidden band is adjustable within the range of 1.0eV to 2.4 eV; the characteristics of high photoelectric conversion efficiency and the like have become research hotspots in the photovoltaic field. CuInSe₂The common structure of the base thin-film solar cell is SLG/Mo/CIS/CdS/i-ZnO/AZO/Ag and Al. Wherein CIS (CuInSe)₂) The absorbing layer of sunlight belongs to I-III-VI family chalcogenide semiconductor materials, and the preparation of the absorbing layer plays an important role and is related to reducing cost, improving efficiency and realizing industrialization.

The current methods for preparing the copper indium selenium film mainly comprise a vacuum method and a non-vacuum method. Common vacuum methods mainly comprise a multi-component co-evaporation method, a sputtering method, a metal prefabricated layer selenization method and the like, and the vacuum method has the defects of complex process control parameters, high cost, problems in uniformity of large-area films, more material waste and the like. The non-vacuum method mainly comprises a liquid phase epitaxy method, an electrochemical deposition method, a continuous ion layer adsorption reaction method, a full solution method, a nanocrystalline ink method and the like. The nanocrystalline ink method is a new potential absorption layer film preparation technology which is rapidly developed in recent years. The method uses solution chemical synthesis nanocrystalline to prepare stable dispersed colloidal ink, and performs film preparation through the coating form of the ink. Compared with other methods, the method has the advantages of no requirement of expensive equipment, low manufacturing cost; the stoichiometric quantity of the solution synthesized nano-crystal is uniform and stable, large-area film preparation can be carried out, and a Roll to Roll technology can be applied to prepare flexible batteries; rare elements In, Ga and Se are less wasted, and compared with a vacuum gas phase technology, the loss and pollution of raw materials are less.

However, in the method, a dispersing agent is used for dispersing the previously obtained CIS nanocrystals into a corresponding solvent, carbon is inevitably introduced into the CIS film, and the existence of the carbon often causes the battery to have higher series resistance, so that the performance of the battery is influenced; on the other hand, the CIS has a high melting point, the CIS cannot be changed into a molten state at the annealing temperature of about 500 ℃, the film is difficult to densify, the obtained nanocrystalline aggregation structure has small crystal grains and a plurality of structural defects, and the performance of the CIS-based thin film solar cell is influenced.

Disclosure of Invention

The invention aims to overcome the defects of the prior art and provides a method for preparing a copper indium diselenide film by using an immersion and drawing process with indium selenide and monovalent copper as intermediates, wherein In is utilized₂Se₃As a support layer with Cu⁺Stacking to obtain prefabricated layer, selenizing Cu in annealing process⁺Reacting with Se to generate a low-melting Cu-Se compound, rapidly diffusing at high temperature to realize the densification of the film, and mutually diffusing Cu and In the process to obtain the CIS ternary chalcopyrite absorption layer. The method has the following advantages: low cost, easy mass production, compact absorption layer and no impurity phase.

The technical purpose of the invention is realized by the following technical scheme.

A method for preparing a copper indium selenide film by using an immersion and lifting process with indium selenide and monovalent copper as intermediates comprises the following steps:

step 1, standing Mo glass in a manner of being vertical to indium selenide nano ink, then carrying out lifting and pulling, and repeating; standing the Mo glass in a monovalent copper solution perpendicularly, then pulling and repeating to obtain a CIS prefabricated layer;

in the step 1, Mo glass is pretreated, ultrasonically cleaned for 30-40 min by using isopropanol, distilled water and absolute ethyl alcohol respectively, and dried in a clean environment for later use.

In the step 1, in the monovalent copper solution, a mixed solution of absolute ethyl alcohol and absolute ethylenediamine is used as a solvent, and the volume ratio of the absolute ethyl alcohol to the absolute ethylene diamine is (3-5): 1, adding CuCl powder into the mixed solution, and fully stirring to dissolve the CuCl powder to obtain Cu with the concentration of 0.12-0.18 mol/L⁺And (3) solution.

In step 1, indium selenide nano-ink (i.e. In)₂Se₃Nano ink), absolute ethyl alcohol is used as a dispersing solvent, and the concentration is 0.075-0.125 mol/L. In₂Se₃Nano meterThe ink is prepared by a method described In the prior art, specifically referring to Multi-morpholinological group of Nano-structured In2Se3 by Ambient environmental pressure polyethylene based solutions Synthesis, Tongfei Li, Jiann Wang, Junyun Lai, Xuuerng Zheng, Weiyan Liu, Junna Ji, Hui Liu, Zhengguo Ji, PII, S0925-8388 (30090-6 DOI, 10.1016/j. janl com.2015.05.193 Reference LCOM 34315, Journal of alloys and company JA, Received Date 8 July Revised Date:28 May modified Date: 201429; specifically, the preparation method can be carried out as follows:

adding 0.3-0.5 mmol of InCl₃·4H₂Dissolving O in triethylene glycol to obtain a cation precursor solution of 0.03-0.05 mol/L; taking 1.5 times of InCl₃·4H₂Adding Se and polyvinylpyrrolidone (PVP) with a molar ratio of O into triethylene glycol (wherein the ratio of Se to PVP is (4.5-7.5) mmol:1g, namely the molar mass ratio) to obtain an anion precursor solution of 0.01125-0.01875 mol/L; placing the anion precursor solution in a reflux device, vacuumizing, introducing inert protective gas (such as nitrogen, helium or argon) to remove oxygen in the water solution (such as 5-10 min), adding 0.4-0.5 mL of hydrazine hydrate as a reducing agent to reduce Se (the proportion of triethylene glycol to hydrazine hydrate is 1mol (1-1.25) L, namely the molar volume ratio) at room temperature (such as 20-25 ℃), stirring and heating the mixed solution to 235-245 ℃, then quickly injecting the cation precursor solution into the reflux device, preserving heat and refluxing for 25-35 min at 215-225 ℃, and cooling to room temperature; centrifuging the solution obtained by the reaction at a high speed (8000-10000 r/min, 15-30 min), and repeatedly centrifuging and cleaning for 4-6 times (8000-10000 r/min, 10-15 min) by using excessive absolute ethyl alcohol; ultrasonically dispersing the obtained product In absolute ethyl alcohol to obtain In₂Se₃And (5) the nano ink is ready for use.

In step 1, Mo glass is placed perpendicular to In₂Se₃Standing the nano ink for 4-6 s, pulling out, and repeating the step for 1 time after the ethanol solvent on the Mo glass is completely volatilized; then, the Mo glass is vertical to the monovalent copper solution, and is lifted out after standing for 1-3 s so as to completely volatilize the solvent; the lifting coating is a cycle, and 10-15 continuous operations are carried outAnd circulating to obtain the CIS prefabricated layer.

Step 2, placing the Mo glass plated with the CIS prefabricated layer obtained in the step 1 into a reaction container containing selenium powder, heating to 450-550 ℃ from room temperature of 20-25 ℃ at a heating rate of 5-10 ℃/min under an inert protective atmosphere, carrying out heat preservation reaction for 30-60 min, and cooling to room temperature along with a furnace to obtain a copper indium selenium film (namely, CuInSe film)₂A film).

In step 2, the reaction vessel is a graphite crucible.

In step 2, a tube furnace is used for the temperature-raising and holding reaction.

In step 2, the inert protective atmosphere is nitrogen, helium or argon.

In the step 2, the temperature is increased to 480-520 ℃ at a heating rate of 8-10 ℃/min, and the reaction is carried out for 30-40 min under heat preservation.

In the step 2, selenium powder is added into the reaction vessel, and the selenium powder and the Mo glass plated with the CIS prefabricated layer are subjected to heat preservation reaction together in the reaction vessel, so that the selenium powder supplements the element selenium for the CIS prefabricated layer.

The copper indium selenide film prepared by the method is applied to the preparation of a copper indium selenide film-based solar cell.

The copper indium diselenide film prepared by the method of the invention is subjected to corresponding phase and shape test analysis. And (3) testing the forbidden band width of the obtained product by using a UV-3600 ultraviolet-visible light-near infrared spectrophotometer to obtain an absorption spectrogram, and calculating the forbidden band width by using a Tauc's formula. The electrical properties of the film were judged by a hall tester (Accent HL5500PC, England) to test the resistivity, the electrical mobility and the carrier concentration. According to the process described in this patent, a compact single chalcopyrite phase copper indium diselenide CuInSe with a grain size of 2-3 μm is obtained₂A film having a forbidden band width of 1.04-1.05 eV and a hole concentration of (2.20-2.41) × 10¹⁶cm^-3The electric mobility is 7.23-7.61 cm²V^-1S^-1A resistivity of 53.2 to 61.3. omega. cm, and a built-up CuInSe₂The potential capability of the base thin film solar cell. In contrast to the nano-ink method In the literature₂Se₃And Cu⁺Alternative lifterThe crystal grain size and the compactness of the film are obviously improved.

The invention adopts a hot injection method to prepare In₂Se₃Nano ink of In₂Se₃As a support layer, by reacting with Cu⁺And (4) laminating the solution at room temperature, and selenizing and annealing to obtain the CIS film. In this process, In₂Se₃Nano ink and Cu⁺Repeatedly and alternately pulling In the solution₂Se₃Not only provides In and Se sources, but also plays a role of supporting, so that the thickness of the prefabricated layer film reaches 2 mu m after 10 cycles. In₂Se₃The surface energy of the nano particles is high, the interface has high energy after lamination, the high interface energy in sintering becomes the driving force of atom movement, the atom diffusion and the cavity shrinkage near the interface are facilitated, and in addition, the Cu⁺Reacting with Se vapor to obtain low-melting liquid-phase Cu-Se compound, and encapsulating In₂Se₃The nano particles are beneficial to mutual diffusion of Cu and In, so that a compact CIS film is obtained.

Drawings

FIG. 1 is a phase analysis diagram of a thin film obtained by selenization at 500 ℃ in example 1 of the present invention.

FIG. 2 is a scanning and energy spectrum of the film selenized at 500 ℃ in example 1 of the present invention.

Detailed Description

The technical scheme of the invention is further explained by combining specific examples.