阅读说明：本技术 铜铟镓硒太阳能电池硫化镉层的制备方法、太阳能电池及铜铟镓硒层上生长硫化镉层的方法 (Preparation method of cadmium sulfide layer of copper-indium-gallium-selenium solar cell, solar cell and method for growing cadmium sulfide layer on copper-indium-gallium-selenium layer ) 是由 左悦 孙合成 于 2019-02-25 设计创作，主要内容包括：本发明涉及一种铜铟镓硒太阳能电池的硫化镉层制备方法、太阳能电池及铜铟镓硒层上生长硫化镉层的方法,所述铜铟镓硒太阳能电池的硫化镉层制备方法包括：预设有铜铟镓硒层的衬底置于酒石酸钾溶液中浸泡,使得酒石酸钾溶液中的至少部分钾离子扩散进铜铟镓硒层中；向酒石酸钾溶液中加入镉盐和碱,充分混合得到混合溶液,混合溶液中含有酒石酸与镉的络合物；加热混合溶液,使得络合物中的镉离子扩散进铜铟镓硒层中,并且使铜铟镓硒层的表面含有至少部分镉离子；以及向混合溶液中加入硫脲,充分反应,在铜铟镓硒层上生长出硫化镉层。采用酒石酸钾代替现有技术中的氨水,使用酒石酸钾制备的硫化镉层质量和稳定性都大大提高了。(The invention relates to a preparation method of a cadmium sulfide layer of a copper indium gallium selenide solar cell, the solar cell and a method for growing the cadmium sulfide layer on the copper indium gallium selenide layer, wherein the preparation method of the cadmium sulfide layer of the copper indium gallium selenide solar cell comprises the following steps: soaking the substrate with the copper-indium-gallium-selenium layer in a potassium tartrate solution to enable at least part of potassium ions in the potassium tartrate solution to diffuse into the copper-indium-gallium-selenium layer; adding cadmium salt and alkali into potassium tartrate solution, and fully mixing to obtain mixed solution, wherein the mixed solution contains tartaric acid and cadmium complex; heating the mixed solution to enable cadmium ions in the complex to diffuse into the copper indium gallium selenide layer and enable the surface of the copper indium gallium selenide layer to contain at least part of cadmium ions; and adding thiourea into the mixed solution, fully reacting, and growing a cadmium sulfide layer on the copper indium gallium selenide layer. The potassium tartrate is adopted to replace ammonia water in the prior art, and the quality and the stability of the cadmium sulfide layer prepared by using the potassium tartrate are greatly improved.)

1. A preparation method of a cadmium sulfide layer of a copper-indium-gallium-selenium solar cell is characterized by comprising the following steps:

soaking the substrate (1) with the copper indium gallium selenide layer (2) in a potassium tartrate solution to enable at least part of potassium ions in the potassium tartrate solution to diffuse into the copper indium gallium selenide layer (2);

adding cadmium salt and alkali into the potassium tartrate solution, and fully mixing to obtain a mixed solution, wherein the mixed solution contains a complex of tartaric acid and cadmium;

heating the mixed solution to enable cadmium ions in the complex to diffuse into the copper indium gallium selenide layer (2) and enable the surface of the copper indium gallium selenide layer (2) to contain at least part of cadmium ions; and

and adding thiourea into the mixed solution, fully reacting, and growing a cadmium sulfide layer (3) on the copper indium gallium selenide layer (2).

2. The preparation method according to claim 1, characterized in that the step of immersing the substrate (1) pre-provided with the CIGS layer (2) in a potassium tartrate solution comprises:

the concentration of the potassium tartrate solution is 2-4mol/L, and the soaking time is 5-6 min.

3. The method according to claim 1, wherein in the step of adding a cadmium salt and a base to the potassium tartrate solution:

the concentration of the cadmium salt is 1.5-7 mol/L;

the concentration of the alkali is 0.05-0.5 mol/L.

4. The method of claim 1, wherein the step of heating the mixed solution comprises:

heating the mixed solution to 50-60 ℃ and maintaining for 1-3 min.

5. The method according to claim 1, wherein the adding thiourea to the mixed solution step:

the thiourea is thiourea crystal or thiourea solution with the concentration of 1-2 mol/L.

6. The method according to claim 1, wherein the step of adding thiourea to the mixed solution and reacting sufficiently comprises:

adding thiourea, and heating to 60-85 deg.C for 5-20 min.

7. The method according to claim 1, wherein the concentrations of the solutes after the addition of thiourea to the mixed solution are:

potassium tartrate: 0.05-1.5 mol/L; cadmium salt: 0.5-2.5 mol/L; thiourea: 0.02-0.5 mol/L; alkali: 0.001-0.1 mol/L.

8. The production method according to claim 7, characterized in that, after adding thiourea to the mixed solution:

the pH of the solution is 8-13.

9. The method according to claim 1, wherein the base is sodium hydroxide or potassium hydroxide.

10. The method according to claim 1, wherein after the step of growing the cadmium sulfide layer (3) on the CIGS layer (2), the method further comprises:

taking out the substrate;

washing with deionized water; and

and (4) drying by using high-pressure gas.

11. A solar cell comprising a cadmium sulfide layer prepared by the method for preparing a cadmium sulfide layer of a copper indium gallium selenide solar cell according to any one of claims 1 to 10.

12. A method for growing a cadmium sulfide layer on a copper indium gallium selenide layer, the method for growing the cadmium sulfide layer comprising:

soaking the copper indium gallium selenide layer (2) in a potassium tartrate solution to enable at least part of potassium ions in the potassium tartrate solution to diffuse into the copper indium gallium selenide layer (2);

adding cadmium salt and alkali into the potassium tartrate solution, and fully mixing to obtain a mixed solution, wherein the mixed solution contains a complex of tartaric acid and cadmium;

heating the mixed solution to enable cadmium ions in the complex to diffuse into the copper indium gallium selenide layer (2) and enable the surface of the copper indium gallium selenide layer (2) to contain at least part of cadmium ions; and

and adding thiourea into the mixed solution, fully reacting, and growing a cadmium sulfide layer (3) on the copper indium gallium selenide layer (2).

13. The method of claim 12, wherein the step of heating the mixed solution comprises:

heating the mixed solution to 50-60 ℃ and maintaining for 1-3 min.

14. The method according to claim 12, wherein the concentrations of the solutes after the addition of thiourea to the mixed solution are:

potassium tartrate: 0.05-1.5 mol/L; cadmium salt: 0.5-2.5 mol/L; thiourea: 0.02-0.5 mol/L; alkali: 0.001-0.1 mol/L.

15. The method of claim 12, wherein the step of adding thiourea to the mixed solution and fully reacting comprises:

adding thiourea, and heating to 60-85 deg.C for 5-20 min.

Technical Field

The invention relates to the technical field of solar cells, in particular to a preparation method of a cadmium sulfide layer of a copper indium gallium selenide solar cell, the solar cell and a method for growing the cadmium sulfide layer on the copper indium gallium selenide layer.

Background

The copper indium gallium selenide thin-film solar cell has the characteristics of high photoelectric conversion efficiency, small material consumption, light weight, flexibility and the like, is widely concerned, and is considered to be a second-generation solar cell with great commercial prospect. Generally, the thin film solar cell sequentially comprises a substrate, a back electrode, a copper indium gallium selenide absorption layer, a cadmium sulfide layer and an upper electrode from bottom to top. The cadmium sulfide layer mainly plays a role in adjusting lattice matching between the absorption layer and the window layer, protecting the absorption layer and avoiding being damaged by a subsequent preparation process, and the thickness of the cadmium sulfide layer is 10-100 nm. The traditional chemical water bath method for preparing the cadmium sulfide film is to utilize cadmium salt and thiourea to carry out complex decomposition reaction in an ammonia solution to generate cadmium sulfide on a substrate so as to obtain the cadmium sulfide film. The method has simple equipment and can realize low temperature and large-area deposition; however, in the coating process, the ammonia content can change, thereby affecting the quality of the film. Meanwhile, ammonia water is strongly irritant and corrosive to eyes, skin and nose of a human body. In addition, in the process of preparing the cadmium sulfide film, the situation that ammonia gas molecules are adsorbed on the surface of the cadmium sulfide film to easily cause pinholes is inevitable, and the short circuit of the battery is possibly caused.

Disclosure of Invention

In order to solve the problems in the prior art, the invention provides a preparation method of a cadmium sulfide layer of a copper-indium-gallium-selenium solar cell, the solar cell and a method for growing the cadmium sulfide layer on the copper-indium-gallium-selenium layer.

A preparation method of a cadmium sulfide layer of a copper-indium-gallium-selenium solar cell comprises the following steps:

soaking the substrate with the copper indium gallium selenide layer in a potassium tartrate solution to enable at least part of potassium ions in the potassium tartrate solution to diffuse into the copper indium gallium selenide layer;

adding cadmium salt and alkali into the potassium tartrate solution, and fully mixing to obtain a mixed solution, wherein the mixed solution contains a complex of tartaric acid and cadmium;

heating the mixed solution to enable cadmium ions in the complex to diffuse into the copper indium gallium selenide layer and enable the surface of the copper indium gallium selenide layer to contain at least part of the cadmium ions; and

and adding thiourea into the mixed solution, fully reacting, and growing a cadmium sulfide layer on the copper indium gallium selenide layer.

Further, the step of soaking the substrate with the copper indium gallium selenide layer in the potassium tartrate solution comprises the following steps:

the concentration of the potassium tartrate solution is 2-4mol/L, and the soaking time is 5-6 min.

Further, in the step of adding the cadmium salt and the alkali into the potassium tartrate solution:

the cadmium salt is a cadmium salt solution with the concentration of 1.5-7 mol/L;

the concentration of the alkali is 0.05-0.5 mol/L.

Further, the step of heating the mixed solution includes:

heating the mixed solution to 50-60 ℃ and maintaining for 1-3 min.

Further, in the step of adding thiourea to the mixed solution:

the thiourea can be thiourea crystals or thiourea solution with the concentration of 1-2 mol/L.

Further, the adding thiourea into the mixed solution and fully reacting comprises the following steps:

adding thiourea, and heating to 60-85 deg.C for 5-20 min.

Further, after thiourea is added into the mixed solution, the concentration of each solute in the solution when the solution is uniformly stirred is as follows:

potassium tartrate: 0.05-1.5 mol/L; cadmium salt: 0.5-2.5 mol/L; thiourea: 0.02-0.5 mol/L; alkali: 0.001-0.1 mol/L.

Further, after adding thiourea to the mixed solution:

the pH of the solution is 8-13.

Further, the alkali is sodium hydroxide or potassium hydroxide.

Further, the alkali is potassium hydroxide.

Further, after the step of growing the cadmium sulfide layer on the copper indium gallium selenide layer, the method further comprises the following steps:

taking out the substrate;

washing with deionized water; and

and (4) drying by using high-pressure gas.

Based on the same invention idea, the invention also provides a solar cell, which comprises the cadmium sulfide layer prepared by the preparation method of the cadmium sulfide layer of the copper indium gallium selenide solar cell.

Based on the same invention idea, the invention also provides a method for growing the cadmium sulfide layer on the copper indium gallium selenide layer, and the method for growing the cadmium sulfide layer comprises the following steps:

soaking the copper indium gallium selenide layer in a potassium tartrate solution to enable at least part of potassium ions in the potassium tartrate solution to diffuse into the copper indium gallium selenide layer;

adding cadmium salt and alkali into the potassium tartrate solution, and fully mixing to obtain a mixed solution, wherein the mixed solution contains a complex of tartaric acid and cadmium;

heating the mixed solution to enable cadmium ions in the complex to diffuse into the copper indium gallium selenide layer and enable the surface of the copper indium gallium selenide layer to contain at least part of the cadmium ions; and

and adding thiourea into the mixed solution, fully reacting, and growing a cadmium sulfide layer on the copper indium gallium selenide layer.

Further, the step of heating the mixed solution includes:

heating the mixed solution to 50-60 ℃ and maintaining for 1-3 min.

Further, the concentrations of the solutes after thiourea is added to the mixed solution are respectively as follows:

potassium tartrate: 0.05-1.5 mol/L; cadmium salt: 0.5-2.5 mol/L; thiourea: 0.02-0.5 mol/L; alkali: 0.001-0.1 mol/L.

Further, the adding thiourea into the mixed solution and fully reacting comprises the following steps:

adding thiourea, and heating to 60-85 deg.C for 5-20 min.

Compared with the closest prior art, the technical scheme of the invention has the following advantages:

according to the preparation method of the cadmium sulfide layer of the CIGS solar cell, potassium tartrate is adopted to replace ammonia water in the prior art to prepare a pretreatment solution, the ammonia water is avoided being used in the subsequent reaction step, the harm of the ammonia water to human bodies is avoided, the problem of pinholes caused by the adsorption of ammonia water molecules is also avoided, and the quality and the stability of the cadmium sulfide layer prepared by using the potassium tartrate are greatly improved.

Drawings

FIG. 1 is a flow chart of a method for preparing a cadmium sulfide layer of a CIGS solar cell according to the present invention;

fig. 2 is a cross-sectional view of a solar cell provided by the present invention.

Wherein: 1-a substrate; 2-a copper indium gallium selenide layer; 3-a cadmium sulfide layer; 4-a barrier layer; 5-front electrode.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are some, but not all, embodiments of the present invention. All other embodiments, which can be obtained by a person skilled in the art without any inventive step based on the embodiments of the present invention, are within the scope of the present invention.

It should be noted that the terms "first," "second," and the like in the description and claims of this application and in the drawings described above are used for distinguishing between similar elements and not necessarily for describing a particular sequential or chronological order. It should be understood that the data so used may be interchanged under appropriate circumstances such that embodiments of the application described herein may be used. Furthermore, the terms "comprises," "comprising," and "having," and any variations thereof, are intended to cover a non-exclusive inclusion, such that a process, method, system, article, or apparatus that comprises a list of steps or elements is not necessarily limited to those steps or elements expressly listed, but may include other steps or elements not expressly listed or inherent to such process, method, article, or apparatus.

In this application, the terms "upper", "lower", "inner", "middle", "outer", "front", "rear", and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings. These terms are used primarily to better describe the present application and its embodiments, and are not used to limit the indicated devices, elements or components to a particular orientation or to be constructed and operated in a particular orientation.

Moreover, some of the above terms may be used to indicate other meanings besides the orientation or positional relationship, for example, the term "on" may also be used to indicate some kind of attachment or connection relationship in some cases. The specific meaning of these terms in this application will be understood by those of ordinary skill in the art as appropriate.

Furthermore, the terms "disposed," "connected," and "secured" are to be construed broadly. For example, "connected" may be a fixed connection, a detachable connection, or a unitary construction; can be a mechanical connection, or an electrical connection; may be directly connected, or indirectly connected through intervening media, or may be in internal communication between two devices, elements or components. The specific meaning of the above terms in the present application can be understood by those of ordinary skill in the art as appropriate.

It should be noted that the embodiments and features of the embodiments in the present application may be combined with each other without conflict. The present application will be described in detail below with reference to fig. 1 and 2 and examples 1 to 6.