阅读说明：本技术 一种柔性高吸收率的薄膜太阳能电池 (Flexible high-absorption rate thin film solar cell ) 是由 马立云 姚婷婷 李刚 沈洪雪 彭赛奥 金克武 王天齐 杨扬 甘治平 彭寿 于 2019-11-16 设计创作，主要内容包括：本发明公开一种柔性高吸收率的薄膜太阳能电池,包括柔性基底,柔性基底顶面由下至上依次层叠有前电极、缓冲层、吸收层、背接触层与保护层,吸收层为CdTe薄膜,前电极包含由下至上依次层叠的下阻隔层、微结构层、透明导电层与上阻隔层；微结构层为单分散SiO<Sub>2</Sub>小球薄膜,SiO<Sub>2</Sub>小球直径为100～500 nm；缓冲层的厚度为40～120nm；吸收层的厚度为1500～2500nm；背接触层的厚度为5～30nm；保护层的厚度为10～40nm；该薄膜太阳能电池能够提高对太阳能的吸收率,增强薄膜太阳能电池的整体性能。(The invention discloses a flexible high-absorptivity thin-film solar cell, which comprises a flexible substrate, wherein a front electrode, a buffer layer, an absorption layer, a back contact layer and a protective layer are sequentially laminated on the top surface of the flexible substrate from bottom to top, the absorption layer is a CdTe thin film, and the front electrode comprises a lower barrier layer, a microstructure layer, a transparent conducting layer and an upper barrier layer which are sequentially laminated from bottom to top; the microstructure layer is monodisperse SiO 2 Small spherical film, SiO 2 The diameter of the small ball is 100-500 nm; the thickness of the buffer layer is 40-120 nm; the thickness of the absorption layer is 1500-2500 nm; the thickness of the back contact layer is 5-30 nm; the thickness of the protective layer is 10-40 nm; the thin film solar cell can improve the absorptivity of solar energy and enhance the performance of the thin film solar cellOverall performance.)

1. A flexible high-absorptivity thin-film solar cell comprises a flexible substrate, wherein a front electrode, a buffer layer, an absorption layer, a back contact layer and a protection layer are sequentially laminated on the top surface of the flexible substrate from bottom to top, and the absorption layer is a CdTe thin film;

the lower barrier layer is TiO₂、ZnO、Al₂O₃SnO or In₂O₃The thickness of the lower barrier layer is 20-80 nm; the microstructure layer is monodisperse SiO₂Small spherical film, SiO₂The diameter of the small ball is 100-500 nm; the transparent conducting layer is a BZO, AZO, GZO, IGZO or ITO film, and the thickness of the transparent conducting layer is 600-1000 nm; the upper barrier layer is TiO₂、ZnO、Al₂O₃SnO or In₂O₃The thickness of the upper barrier layer is 15-60 nm;

the thickness of the buffer layer is 40-120 nm; the thickness of the absorption layer is 1500-2500 nm; the thickness of the back contact layer is 5-30 nm; the thickness of the protective layer is 10-40 nm.

2. The flexible high absorption rate thin film solar cell according to claim 1, wherein the top surface of the transparent conductive layer is a concave-convex textured structure.

3. The flexible high absorption thin film solar cell according to claim 1 or 2, wherein the flexible substrate is a polymer substrate or a metal flexible substrate.

4. A flexible high absorption thin film solar cell according to claim 1 or 2, wherein the buffer layer is a CdS, ZnS or InS thin film.

5. The flexible high absorption thin film solar cell according to claim 1 or 2, wherein the back contact layer is a Cu, Zn, Mo, Ti, Al, Ag or Au thin film.

6. The flexible high absorption thin film solar cell according to claim 1 or 2, wherein the protective layer is an Au, Zn, Pt, Zr or Ti thin film.

7. The flexible high absorption thin film solar cell according to claim 3, wherein the polymer substrate is polyimide or polybenzimidazole.

8. The flexible high absorption rate thin film solar cell according to claim 3, wherein the metal flexible substrate is made of iron-nickel alloy, stainless steel, aluminum foil, titanium foil, molybdenum foil or copper foil.

Technical Field

The invention relates to the technical field of thin film solar cells, in particular to a flexible high-absorptivity thin film solar cell.

Background

At present, a thin film solar cell is rapidly developing as an efficient energy product, and has become a new hotspot and a new trend of the development of the international photovoltaic market due to the fact that the thin film solar cell is relatively lighter in weight, smooth in appearance and relatively low in manufacturing cost.

At present, there are 3 types of thin film solar cells that can be industrially produced in a large scale: silicon-based thin film solar cells, Copper Indium Gallium Selenide (CIGS) thin film solar cells, and cadmium telluride (CdTe) thin film solar cells. The cadmium telluride thin film solar cell is relatively simplest in structure, a single-phase CdTe crystal thin film can be easily prepared, and the preparation method is more. Most of the thin-film solar cells are glass substrates, and the flexible thin-film solar cells are easy to carry due to light weight, folding property, bending property and obvious cost reduction, so that the flexible thin-film solar cells are beneficial to large-scale production, can be widely applied to portable emergency charging backpacks, photovoltaic tents, photovoltaic curtains, photovoltaic roofs, solar automobiles and the like, have wide application spaces, and are beneficial to the sustainable and healthy development of the photovoltaic industry in China.

However, the conventional cadmium telluride thin film solar cell has low absorptivity, and the development of the thin film solar cell is restricted.

Disclosure of Invention

The invention aims to provide a flexible high-absorptivity thin-film solar cell, which can improve the absorptivity of solar energy and enhance the overall performance of the thin-film solar cell.

The technical scheme adopted by the invention for solving the technical problems is as follows:

a flexible high-absorptivity thin-film solar cell comprises a flexible substrate, wherein a front electrode, a buffer layer, an absorption layer, a back contact layer and a protection layer are sequentially laminated on the top surface of the flexible substrate from bottom to top, and the absorption layer is a CdTe thin film;

the lower barrier layer is TiO₂、ZnO、Al₂O₃SnO or In₂O₃The thickness of the lower barrier layer is 20-80 nm; the microstructure layer is monodisperse SiO₂Small spherical film, SiO₂The diameter of the small ball is 100-500 nm; the transparent conducting layer is a BZO, AZO, GZO, IGZO or ITO film, and the thickness of the transparent conducting layer is 600-1000 nm; the upper barrier layer is TiO₂、ZnO、Al₂O₃SnO or In₂O₃The thickness of the upper barrier layer is 15-60 nm;

the thickness of the buffer layer is 40-120 nm; the thickness of the absorption layer is 1500-2500 nm; the thickness of the back contact layer is 5-30 nm; the thickness of the protective layer is 10-40 nm.

Furthermore, the top surface of the transparent conducting layer is of a concave-convex suede structure.

Further, the flexible substrate is a polymer substrate or a metal flexible substrate.

Further, the buffer layer is a CdS, ZnS or InS thin film.

Further, the back contact layer is a Cu, Zn, Mo, Ti, Al, Ag or Au film.

Further, the protective layer is an Au, Zn, Pt, Zr or Ti film.

Further, the polymer substrate is made of polyimide or polybenzimidazole.

Furthermore, the metal flexible substrate is made of iron-nickel alloy, stainless steel, aluminum foil, titanium foil, molybdenum foil or copper foil.

The invention has the beneficial effects that:

the flexible substrate is a polymer substrate or a metal flexible substrate, and is light in weight, foldable, bendable and convenient to carry, so that the surrounding type sputtering deposition can be adopted, the large-scale production is facilitated, and the cost is obviously reduced.

And the front electrode adopts a composite structure of multiple layers of films, the lower blocking layer can effectively prevent the thin-film solar cell from electric leakage, the transmittance of the front electrode is increased, the pollution from the substrate can be blocked, and the light transmittance and the electric conductivity of the transparent conductive layer are prevented from being influenced.

The microstructure layer can reduce the reflectivity of the front electrode, and is beneficial to the formation of a surface microstructure of the transparent conducting layer, so that the light transmittance of the front electrode is effectively increased, the absorption of the solar cell absorption layer on sunlight is enhanced, and the light energy utilization rate is improved.

And fourthly, the transparent conducting layer can adopt different films, and the material and the preparation method of the transparent conducting layer can be adjusted according to the materials of the absorbing layer and the buffer layer, so that excellent photoelectric performance is realized and the cost is reduced.

Fifthly, the concave-convex suede structure of the transparent conducting layer can reduce the reflectivity of the front electrode, so that the light transmittance of the front electrode is effectively increased, the absorption of the solar cell absorption layer on sunlight is enhanced, and the light energy utilization rate is improved.

And sixthly, the upper blocking layer can be used as middle buffering of the front electrode and the buffering layer, so that the interface state of the front electrode and the buffering layer is reduced, the transmittance of the front electrode is increased, elements in the absorption layer are effectively prevented from diffusing to the transparent conducting layer, the pollution from the substrate can be blocked, and the light transmittance and the conducting performance of the transparent conducting layer are prevented from being influenced.

And seventhly, the buffer layer adopts a CdS, ZnS or InS film, so that the lattice constant is between the front electrode and the absorption layer, and the interface state of the front electrode and the absorption layer is reduced.

And eighthly, the back contact layer adopts a Cu, Zn, Mo, Ti, Al, Ag or Au film, and can form good ohmic contact with the absorption layer and reduce the recombination of a carrier interface.

And the protective layer adopts an Au, Zn, Pt, Zr or Ti film, so that the solar cell is protected from being corroded by acid and alkali to reduce the photoelectric conversion efficiency or generate electric leakage, the weather resistance of the cell is improved, and the service life of the cell is prolonged.

Drawings

The invention is further illustrated with reference to the following figures and examples:

FIG. 1 is a schematic structural view of the present invention;

FIG. 2 is a surface topography of the front electrode of the present invention.

Detailed Description

As shown in fig. 1, the invention provides a flexible high-absorption-rate thin-film solar cell, which comprises a flexible substrate 1, wherein a front electrode 2, a buffer layer 3, an absorption layer 4, a back contact layer 5 and a protection layer 6 are sequentially stacked on the top surface of the flexible substrate 1 from bottom to top, and the absorption layer 4 is a CdTe thin film; as shown in fig. 2, the front electrode 2 includes a lower barrier layer 21, a microstructure layer 22, a transparent conductive layer 23, and an upper barrier layer 24, which are sequentially stacked from bottom to top.

The lower barrier layer 21 is TiO₂、ZnO、Al₂O₃SnO or In₂O₃A thin film, wherein the thickness of the lower barrier layer 21 is 20-80 nm; the microstructure layer 22 is a monodisperse SiO₂Small spherical film, SiO₂The diameter of the small ball is 100-500 nm; the transparent conducting layer 23 is a BZO, AZO, GZO, IGZO or ITO thin film, the thickness of the transparent conducting layer 23 is 600-1000 nm, and preferably, the top surface of the transparent conducting layer 23 is of a concave-convex suede structure; the upper barrier layer 24 is TiO₂、ZnO、Al₂O₃SnO or In₂O₃The film has an upper barrier layer 24 with a thickness of 15 to 60 nm.

The thickness of the buffer layer 3 is 40-120 nm; the thickness of the absorption layer 4 is 1500-2500 nm; the thickness of the back contact layer 5 is 5-30 nm; the thickness of the protective layer 6 is 10 to 40 nm.

Preferably, the flexible substrate 1 is a polymer substrate or a metal flexible substrate, the polymer substrate is polyimide or polybenzimidazole, and the metal flexible substrate is iron-nickel alloy, stainless steel, aluminum foil, titanium foil, molybdenum foil or copper foil. The buffer layer 3 is a CdS, ZnS or InS thin film. The back contact layer 5 is a Cu, Zn, Mo, Ti, Al, Ag or Au film. The protective layer 6 is an Au, Zn, Pt, Zr or Ti thin film.

The foregoing is merely a preferred embodiment of the invention and is not intended to limit the invention in any manner; those skilled in the art can make numerous possible variations and modifications to the present teachings, or modify equivalent embodiments to equivalent variations, without departing from the scope of the present teachings, using the methods and techniques disclosed above. Therefore, any simple modification, equivalent replacement, equivalent change and modification made to the above embodiments according to the technical essence of the present invention are still within the scope of the protection of the technical solution of the present invention.