Heterojunction photovoltaic cell

Abstract

The invention discloses a heterojunction photovoltaic cell which comprises a substrate and a light conversion layer, the substrate comprises a first doping layer, a front intrinsic layer, a base body, a back intrinsic layer and a second doping layer, the light conversion layer comprises a light conversion conductive layer and a first transparent conductive layer, the transparent conductive layer is attached to the first doping layer, and the light conversion conductive layer is attached to the second doping layer. The side, attached to the light conversion conductive layer, of the first transparent conductive layer is provided with a protrusion array used for increasing the contact area between the first transparent conductive layer and the light conversion conductive layer, the second transparent conductive layer is attached to the second doping layer, and the front electrode layer is attached to the light conversion conductive layer. And the back electrode layer is attached to the second transparent conductive layer. The heterojunction photovoltaic cell provided by the invention has the advantages of improving the photoelectric conversion efficiency and stability of the cell and reducing the energy loss.

Description

Technical Field

[0001] The present invention relates to the technical field of photovoltaic cells, in particular to a heterojunction photovoltaic cell. Background Art

[0002] Heterojunction photovoltaic cells in related technologies face challenges in improving light absorption and charge transfer. The structure and working efficiency of UV light transfer films cannot meet the needs and have defects such as large energy loss and weak adhesion. Summary of the invention

[0003] The present invention aims to solve one of the technical problems in the related art to at least some extent. To this end, an embodiment of the present invention provides a heterojunction photovoltaic cell, which has the advantages of improving the photoelectric conversion efficiency and stability of the cell and reducing energy loss.

[0004] According to the heterojunction photovoltaic cell of the embodiment of the present invention, the heterojunction photovoltaic cell includes a substrate and a photoconversion layer, the substrate includes a first doped layer, a front intrinsic layer, a matrix, a back intrinsic layer, and a second doped layer, the photoconversion layer includes a photoconversion conductive layer and a first transparent conductive layer, the transparent conductive layer is bonded to the first doped layer, a protrusion array is arranged on one side where the first transparent conductive layer is bonded to the photoconversion conductive layer to increase the contact area between the first transparent conductive layer and the photoconversion conductive layer, the second transparent conductive layer is bonded to the second doped layer, the front electrode layer is bonded to the photoconversion conductive layer, and the back electrode layer is bonded to the second transparent conductive layer.

[0005] The heterojunction photovoltaic cell according to the embodiment of the present invention has the advantages of improving the photoelectric conversion efficiency and stability of the cell and reducing energy loss.

[0006] In some embodiments, a buffer layer is disposed between the transparent conductive layer and the first doped layer to increase adhesion.

[0007] In some embodiments, the buffer layer is a polyurethane layer.

[0008] In some embodiments, the light-converting conductive layer is doped with a light-converting material for converting UV.

[0009] In some embodiments, the light conversion material is CdSe quantum dots or fluorescent dyes.

[0010] In some embodiments, the doping concentration of the light conversion material in the light conversion conductive layer is uneven, and the doping concentration on the side adjacent to the first transparent conductive layer is higher than the doping concentration on the side adjacent to the front electrode layer.

[0011] In some embodiments, the thickness of the light-converting conductive layer is 0 nm to 100 nm, and the sum of the thickness of the first transparent conductive film layer and the second transparent conductive film layer is 1 nm to 100 nm.

[0012] In some embodiments, an anti-reflection layer is disposed on a side of the light-converting conductive layer away from the first transparent conductive layer.

[0013] In some embodiments, the light-converting and conductive layer is further doped with graphene nanosheets. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 Schematic diagram of the structure of a heterojunction photovoltaic cell according to an embodiment of the present invention.

[0015] Figure numerals: 1. substrate; 2. front intrinsic layer; 3. back intrinsic layer; 4. first doped layer; 5. second doped layer; 6. first transparent conductive layer; 7. photoconductive layer; 8. front electrode layer; 9. second transparent conductive layer; 10. back electrode layer; 11. protrusion array. DETAILED DESCRIPTION

[0016] Embodiments of the present invention are described in detail below, and examples of the embodiments are shown in the accompanying drawings. The embodiments described below with reference to the accompanying drawings are exemplary and intended to be used to explain the present invention, but should not be understood as limiting the present invention.

[0017] According to the heterojunction photovoltaic cell of the embodiment of the present invention, the heterojunction photovoltaic cell comprises a substrate and a photoconversion layer, the substrate comprises a first doped layer 4, a front intrinsic layer 2, a matrix 1, a back intrinsic layer 3, and a second doped layer 5, the photoconversion layer comprises a photoconversion conductive layer 7 and a first transparent conductive layer 6, the transparent conductive layer is bonded to the first doped layer 4, a convex array 11 is arranged on one side of the first transparent conductive layer 6 and the photoconversion conductive layer 7 to increase the contact area between the first transparent conductive layer 6 and the photoconversion conductive layer 7, the second transparent conductive layer 9 is bonded to the second doped layer 5, the front electrode layer 8 is bonded to the photoconversion conductive layer 7, and the back electrode layer 10 is bonded to the second transparent conductive layer 9. The substrate of the heterojunction photovoltaic cell adopts n-type and p-type doped layers to form a pn junction to improve the separation efficiency of electrons and holes.

[0018] The protrusion array 11 of the light conversion layer can be prepared by nanoimprint technology, photolithography technology or chemical vapor deposition (CVD) and other methods. The increased contact area of ​​the protrusion array 11 helps to improve the electrical contact and contact area between the light conversion conductive layer 7 and the first transparent conductive layer 6, thereby reducing the contact resistance, improving the overall efficiency of the battery and improving the adhesion strength between the transparent conductive layer and the light conversion conductive layer 7.

[0019] The heterojunction photovoltaic cell according to the embodiment of the present invention has the advantages of improving the photoelectric conversion efficiency and stability of the cell and reducing energy loss.

[0020] In some embodiments, a buffer layer is disposed between the transparent conductive layer and the first doped layer 4 to increase adhesion.

[0021] Specifically, the buffer layer can be a thin layer of organic or inorganic material, which is used to reduce interface defects and improve the chemical and mechanical bonding between interfaces. The buffer layer material can be a silane coupling agent, aluminum oxide, silicon nitride, etc. The setting of the buffer layer helps to relieve the stress caused by the mismatch of thermal expansion coefficients, thereby improving the long-term stability of the photovoltaic cell, improving the adhesion between the transparent conductive layer and the first doping layer 4, reducing interface defects, and improving the life of the battery.

[0022] In some embodiments, the buffer layer is a polyurethane layer.

[0023] Specifically, the polyurethane layer as a buffer layer has good flexibility and weather resistance, and is suitable for applications in different environments. The thickness and cross-linking density of the polyurethane layer can be adjusted as needed to optimize its performance. The use of the polyurethane layer can improve the bonding strength of the interface while maintaining good light transmittance, improve the mechanical strength and durability of the battery, and maintain a high photoelectric conversion efficiency.

[0024] In some embodiments, the light-converting conductive layer 7 is doped with a light-converting material for converting UV.

[0025] Specifically, the light-converting material doped in the light-converting conductive layer 7 can absorb UV light and convert it into visible light, thereby increasing the absorption spectrum range of the photovoltaic cell. The light-converting material can be a combination or one of a plurality of inorganic or organic nanoparticles, such as quantum dots such as CdSe, CdS, and ZnS. By doping with the light-converting material, the utilization rate of the solar spectrum of the cell can be increased, the overall photoelectric conversion efficiency can be improved, the absorption spectrum of the cell can be broadened, and the photoelectric conversion efficiency of the cell can be improved.

[0026] In some embodiments, the light conversion material is CdSe quantum dots or fluorescent dyes.

[0027] Specifically, CdSe quantum dots or fluorescent dyes as light conversion materials have high light conversion efficiency and good chemical stability, and can effectively convert UV light into visible light, which is more effectively absorbed by the active layer in the photovoltaic cell, improving the cell's absorption capacity in the UV band and increasing the overall photoelectric conversion efficiency.

[0028] In some embodiments, the doping concentration of the light conversion material in the light conversion conductive layer 7 is uneven, and the doping concentration on the side adjacent to the first transparent conductive layer 6 is higher than the doping concentration on the side adjacent to the front electrode layer 8 .

[0029] Specifically, by controlling the uneven distribution of doping concentration, the efficiency of charge transfer and collection can be optimized. The higher doping concentration close to the transparent conductive layer helps improve the efficiency of charge injection, while the lower doping concentration side helps collect charges, optimizes charge transfer, and improves the efficiency and stability of the battery.

[0030] In some embodiments, the thickness of the light-converting conductive layer 7 is 0 nm to 100 nm, and the sum of the thicknesses of the first transparent conductive film layer and the second transparent conductive film layer is 1 nm to 100 nm.

[0031] Specifically, the thickness of the light-converting conductive layer 7 can be 0nm, 10nm, 20nm, 30nm, 40nm, 50nm, 60nm, 70nm or 100nm, etc., and the thickness of the transparent conductive film layer can be 1nm, 4nm, 5nm, 8nm, 10nm, 15nm, 20nm, 24nm, 25nm, 30nm, 35nm, 40nm, 45nm, 50nm, 55nm, 60nm, 65nm, 70nm, 75nm, 80nm, 85nm, 90nm, 95nm, etc. By adjusting the thickness of the light-converting conductive layer 7, light management and optimization can be achieved. Appropriate thickness can ensure sufficient light absorption while maintaining low optical loss, thereby improving the light absorption efficiency and charge transfer performance of the battery.

[0032] In some embodiments, an anti-reflection layer is disposed on a side of the light-converting conductive layer 7 away from the first transparent conductive layer 6 .

[0033] Specifically, the anti-reflection layer can be one or more layers of optical coatings used to reduce the reflection loss of light on the surface of the battery. The material of the anti-reflection layer can be TiO2, SiO2, MgF2, etc., and its thickness and refractive index can be designed as needed. The setting of the anti-reflection layer can increase the transmission path of light inside the battery, improve the absorption rate of light, reduce the reflection loss of light, and improve the photoelectric conversion efficiency of the battery.

[0034] In some embodiments, the light-converting and conductive layer 7 is also doped with graphene nanosheets.

[0035] Specifically, graphene nanosheets can be doped into the light-converting conductive layer 7 as a reinforcing material due to their excellent electrical conductivity and mechanical properties. Doping with graphene nanosheets can improve the conductive network of the light-converting conductive layer 7 and enhance charge transport. The addition of graphene nanosheets helps to improve the overall performance of the light-converting conductive layer 7, including electrical conductivity, mechanical strength and thermal stability, improve the electrical conductivity and mechanical properties of the battery, and enhance its environmental stability.

[0036] In the description of the present invention, it is to be understood that the terms “center”, “longitudinal”, “lateral”, “length”, “width”, “thickness”, “up”, “down”, “front”, “back”, “left”, “right”, “vertical”, “horizontal”, “top”, “bottom”, “inside”, “outside”, “clockwise”, “counterclockwise”, “axial”, “radial”, “circumferential”, etc., indicating orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0037] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of the present invention, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0038] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral one; it can be a mechanical connection, an electrical connection, or communication with each other; it can be a direct connection, or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0039] In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, a first feature being "above", "above" or "above" a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being "below", "below" or "below" a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0040] In the present invention, the terms "one embodiment", "some embodiments", "examples", "specific examples", or "some examples" etc. mean that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the described specific features, structures, materials or characteristics may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0041] Although the embodiments of the present invention have been shown and described above, it is to be understood that the above embodiments are illustrative and are not to be construed as limitations on the present invention. Changes, modifications, substitutions and variations of the above embodiments by those of ordinary skill in the art are all within the scope of protection of the present invention.

Claims

1. A heterojunction photovoltaic cell, characterized in that: include: A substrate, the substrate comprising a first doped layer, a front intrinsic layer, a matrix, a back intrinsic layer, and a second doped layer; A light conversion layer, the light conversion layer comprising a light conversion conductive layer and a first transparent conductive layer, the transparent conductive layer is bonded to the first doped layer, and a protrusion array is provided on one side where the first transparent conductive layer is bonded to the light conversion conductive layer to increase the contact area between the first transparent conductive layer and the light conversion conductive layer; The second transparent conductive layer is bonded to the second doped layer, the front electrode layer is bonded to the light-converting conductive layer, and the back electrode layer is bonded to the second transparent conductive layer;.

2. The heterojunction photovoltaic cell according to claim 1, characterized in that: A buffer layer is disposed between the transparent conductive layer and the first doping layer to increase adhesion.

3. The heterojunction photovoltaic cell according to claim 2, characterized in that: The buffer layer is a polyurethane layer.

4. The heterojunction photovoltaic cell according to claim 1, characterized in that: The light-converting conductive layer is doped with a light-converting material for converting UV.

5. The heterojunction photovoltaic cell according to claim 4, characterized in that: The light conversion material is CdSe quantum dots or fluorescent dyes.

6. The heterojunction photovoltaic cell according to claim 4, characterized in that: The doping concentration of the light-converting material in the light-converting conductive layer is uneven, and the doping concentration on the side adjacent to the first transparent conductive layer is higher than the doping concentration on the side adjacent to the front electrode layer.

7. The heterojunction photovoltaic cell according to claim 1, characterized in that: The thickness of the light-converting conductive layer is 0 nm to 100 nm, and the sum of the thickness of the first transparent conductive film layer and the second transparent conductive film layer is 1 nm to 100 nm.

8. The heterojunction photovoltaic cell according to claim 1, characterized in that: An anti-reflection layer is disposed on a side of the light-converting conductive layer away from the first transparent conductive layer.

9. The heterojunction photovoltaic cell according to claim 1, characterized in that: The light-converting and conducting layer is also doped with graphene nanosheets.

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