Perovskite silicon tandem cell employing a tantalum nitride interlayer and method of fabrication thereof

Abstract

The application relates to a perovskite silicon laminated battery adopting a TaN intermediate layer and a preparation method thereof. The perovskite silicon laminated battery comprises, from bottom to top, a bottom electrode, a silicon bottom battery, a TaN intermediate layer, a perovskite battery and a metal grid electrode. The perovskite silicon laminated battery adopting the TaN intermediate layer has excellent long-wave transmittance, conductivity and stability, can effectively increase the light absorption capacity of the battery, and improves the overall photoelectric conversion efficiency of the perovskite silicon laminated battery. Meanwhile, the production cost of the TaN material is lower, and the overall cost can be reduced in large-scale manufacturing. Furthermore, the TaN intermediate layer in the application has good compatibility with different types of crystalline silicon batteries, and can adapt to various manufacturing processes.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of perovskite batteries, and particularly relates to a perovskite silicon tandem battery adopting a TaN intermediate layer and a preparation method thereof. BACKGROUND

[0002] As a new emerging solar cell technology, perovskite silicon tandem battery has attracted much attention in recent years and triggered a wide research boom in the energy field. Compared with traditional silicon-based solar cells, perovskite silicon tandem battery has many remarkable advantages such as simple process, low raw material cost and high energy conversion efficiency. These characteristics make perovskite silicon tandem battery show great application potential in the field of renewable energy and become one of the important trends in the development of future solar cell technology.

[0003] The intermediate layer plays a crucial role in the tandem solar cell, which provides recombination sites for electrons and holes from the top and bottom cells, promotes the effective recombination of charges and improves the efficiency of the cell. The conductivity, light transmittance and stability of the intermediate layer will directly affect the overall performance of the tandem cell. An ideal intermediate layer should have good electrical conductivity to improve the recombination rate of charges; high optical transmittance to allow light to effectively penetrate to the bottom cell to ensure that the back junction sub-cell obtains sufficient light for photoelectric conversion. By selecting appropriate materials, the intermediate layer can reduce unnecessary light absorption, thereby improving the energy conversion efficiency of the entire tandem cell. By optimizing the performance of the intermediate layer, it is expected to significantly improve the efficiency and reliability of the tandem cell.

[0004] In the prior art, the intermediate layer material is usually selected from conductive oxides, especially transparent conductive indium tin oxide (ITO) thin film. However, the traditional ITO thin film has high reflectivity in the infrared band, which limits its effective utilization of long-wave solar energy. In addition to ITO, other common transparent conductive oxides (TCO) include indium zinc oxide (IZO) and aluminum-doped zinc oxide (AZO). Among them, IZO has good conductivity and transparency, but its stability and conductivity may decrease at high temperatures, affecting the long-term performance of the cell. AZO is relatively low in cost, but its conductivity and optical properties are still inferior to ITO, especially in applications requiring high light transmittance. In addition, using doped polysilicon as an intermediate layer is also an option, but its process is complex and the cost is high. In summary, the intermediate layer materials in the prior art cannot be compatible in long-wave transmittance, conductivity and stability, which limits the development and application of perovskite silicon tandem battery. SUMMARY

[0005] In order to solve the above problems existing in the prior art, the present application provides a perovskite silicon tandem battery adopting a TaN intermediate layer and a preparation method thereof. The technical problem to be solved by the present application is solved by the following technical scheme:

[0006] The first aspect of the present application provides a perovskite silicon tandem battery with a TaN intermediate layer, comprising a bottom electrode, a silicon bottom battery, a TaN intermediate layer, a perovskite battery and a metal grid electrode arranged in sequence from bottom to top.

[0007] In an implementable manner, further comprising: an alloy layer;

[0008] The alloy layer is arranged between the TaN intermediate layer and the perovskite battery.

[0009] In an implementable manner, the material of the alloy layer comprises one of a Ta-Ni alloy mixture, a Ta-Ti alloy mixture and a Ta-Cu alloy mixture; and the thickness of the alloy layer is 1-2 nm.

[0010] In an implementable manner, the perovskite battery is a p-i-n type perovskite battery.

[0011] The p-i-n type perovskite battery comprises a hole transport layer, a perovskite light absorption layer, an electron transport layer, a buffer layer and a transparent electrode layer arranged in sequence from bottom to top.

[0012] In an implementable manner, the electron selection layer in the silicon bottom battery is arranged upward.

[0013] The hole transport layer of the p-i-n type perovskite battery is arranged close to the electron selection layer of the silicon bottom battery.

[0014] In an implementable manner, the perovskite battery is an n-i-p type perovskite battery.

[0015] The n-i-p type perovskite battery comprises an electron transport layer, a perovskite light absorption layer, a hole transport layer, a buffer layer and a transparent electrode layer arranged in sequence from bottom to top.

[0016] In an implementable manner, the hole selection layer in the silicon bottom battery is arranged upward.

[0017] The electron transport layer of the n-i-p type perovskite battery is arranged close to the hole selection layer of the silicon bottom battery.

[0018] In an implementable manner, the silicon bottom battery comprises one of an HJT battery, a TOPCon battery and a PERC battery.

[0019] The second aspect of the present application provides a preparation method of a perovskite silicon tandem battery with a TaN intermediate layer, comprising the following steps:

[0020] Preparation of a TaN intermediate layer on the upper surface of a silicon bottom battery;

[0021] preparing a perovskite cell on the upper surface of the TaN intermediate layer;

[0022] preparing a metal grid electrode on the upper surface of the perovskite cell; and preparing a bottom electrode on the lower surface of the silicon bottom cell.

[0023] In an implementable manner, the TaN intermediate layer is prepared on the upper surface of the silicon bottom cell, comprising:

[0024] The TaN with a thickness of 1-5 nm is prepared on the upper surface of the silicon bottom cell by using a reactive magnetron sputtering technology, so as to form the TaN intermediate layer.

[0025] Compared with the prior art, the present application has the following beneficial effects:

[0026] The perovskite silicon stacked cell with the TaN intermediate layer has excellent long-wave transmittance, conductivity and stability, can effectively increase the light absorption capacity of the cell, and improve the overall photoelectric conversion efficiency of the perovskite silicon stacked cell; at the same time, the production cost of the TaN material is lower, and the overall cost can be reduced in large-scale manufacturing; and the TaN intermediate layer in the present application has good compatibility with different types of crystalline silicon cells, and can adapt to various manufacturing processes. BRIEF DESCRIPTION OF DRAWINGS

[0027] Figure 1 is a structure schematic diagram of a perovskite silicon stacked cell with a TaN intermediate layer provided by an embodiment of the present application;

[0028] Figure 2 is a transmittance diagram of a 2nm TaN thin film provided by an embodiment of the present application;

[0029] Figure 3 is a structure schematic diagram of a p-i-n type perovskite silicon stacked cell provided by an embodiment of the present application;

[0030] Figure 4 is a step schematic diagram of a perovskite silicon stacked cell with a TaN intermediate layer provided by an embodiment of the present application;

[0031] Figure 5 is another structure schematic diagram of a perovskite silicon stacked cell with a TaN intermediate layer provided by an embodiment of the present application. DETAILED DESCRIPTION

[0032] The present application will be further described in detail below in combination with specific embodiments, but the implementation manner of the present application is not limited thereto.

[0033] Embodiment one

[0034] The first aspect of this embodiment provides a perovskite silicon tandem cell using a tantalum nitride (TaN) intermediate layer, see Figure 1 , Figure 1 This is a schematic diagram of the structure of a perovskite silicon tandem cell using a TaN interlayer, provided in an embodiment of the present invention. This embodiment provides a perovskite silicon tandem cell using a TaN interlayer, comprising, arranged from bottom to top, a bottom electrode, a silicon bottom cell, a TaN interlayer, a perovskite cell, and a metal grid electrode.

[0035] In this embodiment, the perovskite cell is a pin-type perovskite cell or a nip-type perovskite cell. The silicon-based cell includes one of an HJT cell, a TOPCon cell, and a PERC cell. The thickness of the TaN intermediate layer is 1 to 5 nm.

[0036] Specifically, TaN has excellent long-wave transmittance, conductivity and stability, which enables the perovskite silicon tandem cell to effectively transmit long-wave light (such as near-infrared light), thereby improving the light absorption capacity of the perovskite silicon tandem cell and improving the overall photoelectric conversion efficiency of the perovskite silicon tandem cell. Furthermore, when the thickness of the TaN intermediate layer is 1 to 5 nm, the ultra-thin characteristics of the TaN intermediate layer can usually further optimize the long-wave transmittance, conductivity and stability, making full use of these properties to exhibit better transmittance. The thickness of the ultra-thin TaN film reduces the reflection and absorption of light when it passes through, thereby improving the long-wave transmittance. However, when the thickness of the TaN intermediate layer is too thin, the conductivity of the TaN film may be insufficient, resulting in a decrease in the transmission efficiency of the carrier interface, causing electrical loss, thereby affecting the overall efficiency of the battery. In addition, film discontinuity or pore phenomena may occur, resulting in the inability of current to pass smoothly, resulting in high resistance and unevenness. However, when the thickness of the TaN interlayer is too thick, it will affect the transmittance of light. The thicker TaN interlayer may block some light from entering, reducing light absorption efficiency and affecting the performance of the battery. Therefore, when the thickness of the TaN interlayer is 1-5nm, the TaN interlayer can exhibit good long-wave transmittance, conductivity and stability. Preferably, the thickness of the TaN interlayer is 2-3nm.

[0037] See Figure 2 , Figure 2 This is a transmittance graph of a 2 nm thick TaN film provided by an embodiment of the present invention. As an intermediate layer material, the transmittance of the material in the near-infrared region is of particular interest. Figure 2As can be seen, the transmittance of TaN tends to increase at near-infrared wavelengths greater than 1000 nm, and even higher, so that the near-infrared part of the solar spectrum can be effectively utilized by TaN films, whether in a two-junction stack or in a three-junction stack cell. Conventional materials such as ITO, on the other hand, show a sharp decrease in transmittance in the near-infrared region, and perform much worse than TaN in the near-infrared region. TaN not only has excellent light transmittance, but also has good electrical conductivity, and in terms of material cost, TaN has better cost-effectiveness compared to some high-cost transparent conductive oxides (such as ITO). Considering cost, electrical conductivity, light transmittance, high-temperature resistance and oxidation resistance, TaN films have great application potential, and TaN films as intermediate layer materials have high value in some applications, especially in high-performance optoelectronic devices that require both light transmittance and electrical conductivity.

[0038] See Figure 3 , Figure 3 is a structural schematic diagram of a p-i-n type perovskite silicon tandem cell provided by an embodiment of the present application. In this embodiment, the perovskite cell is a p-i-n type perovskite cell. The p-i-n type perovskite cell comprises, from bottom to top, a hole transport layer, a perovskite light absorption layer, an electron transport layer, a buffer layer and a transparent electrode layer. The material of the hole transport layer comprises one of CuO, NiO x , 2PACz, Me-4PACz, MeO-4PACz and CuSCN. The material of the perovskite light absorption layer comprises one of Cs 0.05 FA 0.8 MA 0.15 PbI 2.25 Br 0.75 , FA 0.65 MA 0.2 Cs 0.15 PbI 2.4 Br 0.6 , FA 0.5 MA 0.38 Cs 0.12 PbI 2.04 Br 0.96 . The material of the electron transport layer comprises one of PCBM, TiO2, SnO2, ZnO, C 60 . The material of the buffer layer comprises SnO xThe material of the transparent electrode layer includes IZO or ITO. Further, when the perovskite cell is a p-i-n type perovskite cell, the electron selection layer in the silicon bottom cell is arranged upward. The hole transport layer of the p-i-n type perovskite cell is arranged close to the electron selection layer of the silicon bottom cell. For example, the silicon bottom cell is an HJT cell, the n+ amorphous silicon layer is the electron selection layer of the HJT cell, and the p+ amorphous silicon layer is the hole selection layer of the HJT cell. When the perovskite cell is a p-i-n type perovskite cell and the silicon bottom cell is an HJT cell, the perovskite silicon tandem cell provided in the embodiment and adopting the TaN intermediate layer includes, from bottom to top, a bottom electrode, an ITO layer, a p+ amorphous silicon layer, an intrinsic amorphous silicon layer, a single crystal silicon substrate, an intrinsic amorphous silicon layer, an n+ amorphous silicon layer, a TaN intermediate layer, a hole transport layer, a perovskite light-absorbing layer, an electron transport layer, a buffer layer, a transparent electrode layer, and a metal gate line electrode. It should be understood that although the specific structures and materials of the HJT cell, the TOPCon cell, and the PERC cell are different, there are electron selection layers and hole selection layers in the mechanism, and those skilled in the art can clearly distinguish the electron selection layers and hole selection layers in the specific structures of the HJT cell, the TOPCon cell, and the PERC cell.

[0039] In another implementable manner, the perovskite cell is an n-i-p type perovskite cell. The n-i-p type perovskite cell includes, from bottom to top, an electron transport layer, a perovskite light-absorbing layer, a hole transport layer, a buffer layer, and a transparent electrode layer, wherein the material of the electron transport layer includes one of TiN, SnO2, TiO2, and ZnO. The material of the perovskite light-absorbing layer includes one of 0.05 FA 0.8 MA 0.15 PbI 2.25 Br 0.75 , FA 0.65 MA 0.2 Cs 0.15 PbI 2.4 Br 0.6 , FA 0.5 MA 0.38 Cs 0.12 PbI 2.04 Br 0.96The material of the hole transport layer includes one of Spiro-OMeTAD, PEDOT:PSS, CuSCN and PTAA. The material of the buffer layer includes MoO3. The material of the transparent electrode layer includes IZO or ITO. When the perovskite cell is an n-i-p type perovskite cell, the hole selection layer of the silicon bottom cell is arranged upward, and the electron transport layer of the n-i-p type perovskite cell is arranged close to the hole selection layer of the silicon bottom cell. Illustratively, taking the silicon bottom cell as an HJT cell as an example, the n+ amorphous silicon layer is the electron selection layer of the HJT cell, and the p+ amorphous silicon layer is the hole selection layer of the HJT cell. When the perovskite cell is an n-i-p type perovskite cell and the silicon bottom cell is an HJT cell, the perovskite silicon tandem cell adopting the TaN intermediate layer includes, from bottom to top, a bottom electrode, an ITO layer, an n+ amorphous silicon layer, an intrinsic amorphous silicon layer, a single crystal silicon substrate, an intrinsic amorphous silicon layer, a p+ amorphous silicon layer, a TaN intermediate layer, an electron transport layer, a perovskite light-absorbing layer, a hole transport layer, a buffer layer, a transparent electrode layer and a metal gate line electrode.

[0040] The second aspect of the embodiment provides a preparation method of the perovskite silicon tandem cell adopting the TaN intermediate layer, please refer to Figure 4 , Figure 4 is a step schematic diagram of the perovskite silicon tandem cell adopting the TaN intermediate layer provided by the embodiment.

[0041] The preparation method of the perovskite silicon tandem cell adopting the TaN intermediate layer provided by the embodiment includes the following steps:

[0042] S110: preparing a TaN intermediate layer on the upper surface of the silicon bottom cell.

[0043] Specifically, the silicon bottom cell is ultrasonically cleaned with acetone, deionized water and alcohol for 15 minutes and then dried. A TaN intermediate layer with a thickness of 1-5 nm is prepared on the upper surface of the silicon bottom cell by using a reaction magnetron sputtering technology. In the embodiment, the silicon bottom cell is one of an HJT cell, a TOPCon cell and a PERC cell. Illustratively, the thickness of the tantalum nitride film is 1 nm or 2 nm or 3 nm or 4 nm or 5 nm.

[0044] Further, the vacuum chamber is vacuumized to better than 10 -7 Pa, and nitrogen and argon are made to enter the vacuum chamber through a gas flow meter, wherein the argon flow is 50-100 sccm, the nitrogen flow is 10-50 sccm, the temperature is set to 20-100℃, the direct current source power is 100-200 W during sputtering, the sputtering time is 45-180 s, and finally a 2-3 nm tantalum nitride film is obtained, and the preparation of the TaN intermediate layer is completed.

[0045] S120: preparing a perovskite cell on the upper surface of the TaN intermediate layer.

[0046] Specifically, a p-i-n type perovskite cell or an n-i-p type perovskite cell is prepared on the upper surface of the TaN intermediate layer.

[0047] In an implementable manner, the perovskite cell is a p-i-n type perovskite cell. Step S120 comprises the following step: preparing a p-i-n type perovskite cell on the upper surface of the TaN intermediate layer.

[0048] S121: forming a hole transport layer on the upper surface of the TaN intermediate layer.

[0049] Specifically, on the upper surface of the TaN intermediate layer, NiO x is prepared by a magnetron reactive sputtering process. x The film is grown at a pressure of 10 -4 Pa, with high-purity argon introduced at a flow rate of 20-30 sccm, and a power of 50-65 W, to prepare a hole transport layer with a thickness of 15-20 nm on the TaN intermediate layer.

[0050] S122: preparing a perovskite light-absorbing layer on the upper surface of the hole transport layer.

[0051] Illustratively, the material of the perovskite light-absorbing layer is Cs 0.05 FA 0.8 MA 0.15 PbI 2.25 Br 0.75 . The concentration of Cs 0.05 FA 0.8 MA 0.15 PbI 2.25 Br 0.75 perovskite precursor solution is 1.6-1.8 M. After the solution is dissolved with continuous stirring, it is ready for use. The precursor solution is spin-coated on the hole transport layer by a one-step spin coating method. Specifically, the pre-stage rotation speed is 1000-2000 rpm for 5 s, and the post-stage rotation speed is 5000-6000 rpm for 45 s. During the 12th-15th s of the spin coating, 180-200 μL of anti-solvent chlorobenzene is added for extraction. After the spin coating is completed, annealing is performed at 100-120 °C for 10-20 min to prepare the perovskite light-absorbing layer.

[0052] S123: preparing an electron transport layer on the upper surface of the perovskite light-absorbing layer.

[0053] Illustratively, the material of the electron transport layer is C 60 . A layer of 20 nm of C 60 is evaporated on the perovskite light-absorbing layer by a thermal evaporation process. The growth pressure is 10 -4 Pa, and the growth rate is The preparation of the electron transport layer is completed.

[0054] S124: preparing a buffer layer on the upper surface of the electron transport layer.

[0055] For example, the material of the buffer layer is SnO x SnO was prepared by atomic layer deposition (ALD) process. x During the ALD deposition process, the substrate temperature was maintained at 85-100°C, the Sn precursor source was maintained at 55-85°C, and the H2O source was maintained at room temperature. 120-160 cycles were performed to obtain 15-20 nm SnO x Buffer layer.

[0056] S125: preparing a transparent electrode layer on the upper surface of the buffer layer.

[0057] Specifically, indium zinc oxide (IZO) is deposited on the upper surface of the buffer layer by magnetron sputtering process as a transparent electrode with a growth rate of The power is 40-50W, the DC voltage is 99V, and finally a 100nm IZO transparent electrode layer is obtained.

[0058] After step S125 is completed, a pin-type perovskite cell is prepared on the upper surface of the TaN intermediate layer.

[0059] In another achievable embodiment, the perovskite cell is a nip-type perovskite cell. Step S120 includes the following steps: an electron transport layer, a perovskite light absorption layer, a hole transport layer, a buffer layer, and a transparent electrode layer are sequentially formed on the upper surface of the TaN intermediate layer from bottom to top to obtain a nip-type perovskite cell.

[0060] S130: preparing a metal grid electrode on the upper surface of the perovskite cell; and preparing a bottom electrode on the lower surface of the silicon bottom cell.

[0061] Specifically, a 200-500nm metal electrode Ag is prepared on the lower surface of the bottom ITO of the bottom silicon cell, and a 100-200nm metal grid line electrode Ag is prepared on the top of the transparent electrode of the perovskite cell to obtain the perovskite silicon stacked cell provided in this embodiment.

[0062] The perovskite silicon tandem cell with a TaN intermediate layer provided in this embodiment increases the light absorption capacity of the cell through the TaN intermediate layer, thereby improving the overall photoelectric conversion efficiency. The production cost of TaN materials is lower, which can reduce the overall cost during large-scale manufacturing. TaN has good high temperature resistance and oxidation resistance, can maintain its performance under a wider range of conditions, and is adaptable to a variety of application environments. The TaN film has high chemical stability, and is easy to recycle and reuse the bottom components, which helps to reduce costs. In addition, the TaN intermediate layer has good compatibility with different types of crystalline silicon cells and can adapt to various manufacturing processes. The perovskite cell on the top is not only suitable for the preparation of hybrid perovskite solar cells, but also suitable for all-inorganic perovskite solar cells, showing broad application prospects.

[0063] Example 2

[0064] Based on Example 1, this example provides a perovskite silicon tandem cell using a TaN intermediate layer and a method for preparing the same. Figure 5 , Figure 5 This is a schematic structural diagram of another perovskite silicon tandem cell using a TaN intermediate layer provided by an embodiment of the present invention.

[0065] The perovskite silicon tandem cell with a TaN intermediate layer provided in this embodiment includes a bottom electrode, a silicon bottom cell, a TaN intermediate layer, an alloy layer, a perovskite cell, and a metal grid electrode arranged in sequence from bottom to top. That is, the alloy layer is arranged between the TaN intermediate layer and the perovskite cell.

[0066] In this embodiment, the perovskite cell is a pin-type perovskite cell, that is, the perovskite silicon stack cell using a TaN intermediate layer provided in this embodiment includes a bottom electrode, a silicon bottom cell, a TaN intermediate layer, an alloy layer, a hole transport layer, a perovskite light absorption layer, an electron transport layer, a buffer layer, a transparent electrode layer and a metal grid line electrode arranged in sequence from bottom to top.

[0067] In another feasible embodiment, the perovskite cell is a nip-type perovskite cell, that is, the perovskite silicon stacked cell using a TaN intermediate layer includes a bottom electrode, a silicon bottom cell, a TaN intermediate layer, an alloy layer, an electron transport layer, a perovskite light absorption layer, a hole transport layer, a buffer layer, a transparent electrode layer and a metal grid electrode arranged in sequence from bottom to top.

[0068] The method for preparing a perovskite silicon tandem cell using a TaN intermediate layer provided in this embodiment includes the following steps:

[0069] S210: preparing a TaN intermediate layer on the upper surface of the silicon bottom cell.

[0070] Specifically, the silicon-based cell is sequentially cleaned with acetone, deionized water and alcohol for 15 minutes by ultrasonic cleaning, and then dried. A reaction magnetron sputtering technology is used to vacuum the vacuum chamber to better than 10 -7 Pa, and nitrogen and argon are introduced into the vacuum chamber through a gas flow meter, wherein the flow rate of argon is 50-100 sccm, the flow rate of nitrogen is 10-50 sccm, the temperature is set to 20-100°C, the direct current source power is 100-200 W during sputtering, the sputtering time is 30-120 s, after the sputtering is completed, the argon flow rate is increased to 100-150 sccm under the condition that other conditions remain unchanged, and the second stage of sputtering is performed again, so that the content of tantalum in the top layer of the thin film is higher, the sputtering time is about 15-60 s, and finally a 2-3 nm tantalum nitride thin film is obtained, and the TaN intermediate layer is prepared.

[0071] Further, when the room temperature magnetron reaction sputtering metallic TaN is used as the intermediate layer, the TaN thin film has higher long-wave transmittance, can effectively utilize long-wave light compared with common conductive oxides, reduces parasitic absorption of light, and thus increases the light absorption capacity of the cell and improves the overall photoelectric conversion efficiency of the device.

[0072] S220: preparing an alloy layer and a perovskite cell on the upper surface of the TaN intermediate layer.

[0073] In this embodiment, the material of the alloy layer includes one of a Ta-Ni alloy mixture, a Ta-Ti alloy mixture and a Ta-Cu alloy mixture. Further, the Ta-Ni alloy mixture is Ta-Ni-N-O, the Ta-Ti alloy mixture is Ta-Ti-N-O, and the Ta-Cu alloy mixture is Ta-Cu-N-O.

[0074] In an implementable manner, the step S220 includes:

[0075] S221: forming an alloy layer and a hole transport layer on the upper surface of the TaN intermediate layer.

[0076] Specifically, in order to simplify the preparation process, the material of the alloy layer and the hole transport layer is carefully designed in this embodiment, and NiO x or CuO is selected as the hole transport layer, and NiO x or CuO is directly prepared on the upper surface of the TaN intermediate layer, after annealing, the bottom layer and the TaN intermediate layer contact the NiO x or CuO which is collectively converted into a Ta-Ni alloy mixture or a Ta-Cu alloy mixture to form an alloy layer, and the top layer of the NiO xOr CuO directly as a hole transport layer, to achieve one-step preparation of alloy layer and hole transport layer. Further, in S310, the second stage of sputtering of TaN can make the Ta content on the top of the TaN intermediate layer higher, so that the proportion of Ta in the part of the TaN intermediate layer close to the hole transport layer is higher to facilitate better formation of the alloy.

[0077] The material of the alloy layer is Ta-Ni alloy mixture, and the material of the hole transport layer is NiO x For example: on the upper surface of the TaN intermediate layer, NiO is used x The target is deposited by a magnetron reactive sputtering process x The film is grown at a pressure of 10 -4 Pa, high-purity argon gas is introduced at a flow rate of 20-30 seem, and the power is 50-65 W, to prepare a 15-20 nm thick NiO layer on the TaN intermediate layer. x After sputtering, annealing is performed at an annealing temperature of 200-250 °C and in an Ar atmosphere for 20-30 min to form a 1 nm Ta-Ni-N-O alloy mixture.

[0078] Specifically, TaN itself has good stability, but the addition of nickel in the Ta-Ni alloy mixture under high temperature conditions helps to form an alloy layer with stronger stability, thereby enhancing the stability of the TaN intermediate layer. Nickel itself is a good conductive material with higher electrical conductivity than pure tantalum. When nickel is combined with TaN, it can enhance the overall conductivity of the alloy, especially in the case of thin film layers, nickel can effectively reduce the resistance of the alloy.

[0079] In another implementable manner, an alloy layer is obtained by Ta, M co-sputtering on the upper surface of the TaN intermediate layer. M is one of Ni, Ti and Cu, and the co-sputtering atmosphere is nitrogen and oxygen. Then a hole transport layer is prepared on the alloy layer.

[0080] It should be understood that when the perovskite battery is an n-i-p type perovskite battery, TiO2 is selected as the electron transport layer, TiO2 is directly prepared on the upper surface of the TaN intermediate layer, after annealing, the bottom layer of TiO2 and the TaN intermediate layer are converted into Ta-Ti alloy mixture to form the alloy layer, and the top layer of TiO2 or TiN directly as the electron transport layer, to achieve one-step preparation of the alloy layer and the electron transport layer.

[0081] S222: from bottom to top, a perovskite light-absorbing layer, an electron transport layer, a buffer layer and a transparent electrode layer are prepared on the upper surface of the hole transport layer. After step S222, a silicon bottom cell, a TaN intermediate layer, an alloy layer and a p-i-n type perovskite battery are obtained from bottom to top.

[0082] S230: preparing a metal grid electrode on the upper surface of the perovskite cell; and preparing a bottom electrode on the lower surface of the silicon bottom cell.

[0083] Specifically, a 100-200nm metal grid electrode is prepared on the upper surface of the perovskite cell. A 200-500nm electrode metal is prepared on the lower surface of the silicon bottom cell to form a bottom electrode. After step S230, the perovskite silicon tandem cell provided in the embodiment using a TaN intermediate layer is obtained.

[0084] The perovskite silicon tandem cell provided in the embodiment using a TaN intermediate layer increases the light absorption capacity of the cell through the TaN intermediate layer, improves the overall photoelectric conversion efficiency, and further enhances the corrosion resistance and conductivity of the TaN intermediate layer by using an alloy layer, thereby further improving the stability and transmission efficiency of the cell. The common conductive oxide as an intermediate connecting layer cannot effectively utilize long-wave solar energy and has problems such as stability and conductivity decline at high temperatures. In addition, the combination of the bottom cell and the intermediate layer can be recycled, thereby reducing the production cost. The TaN intermediate layer and the alloy layer have strong resistance to the environment and can maintain their performance under a wider range of conditions, thereby adapting to different application environments. Therefore, the top perovskite cell can be prepared using all-inorganic perovskite or organic-inorganic hybrid perovskite, and has a wide application market.

[0085] The above is a further detailed description of the present application in combination with specific preferred embodiments, and the specific implementation of the present application cannot be limited to these descriptions. For ordinary skilled persons in the technical field to which the present application belongs, a number of simple deductions or substitutions can be made without departing from the concept of the present application, and all of them should be considered as falling within the protection scope of the present application.

Claims

1. A perovskite silicon tandem cell employing a TaN interlayer, characterized in that, The bottom electrode, the silicon bottom cell, the TaN intermediate layer, the perovskite cell and the metal grid electrode are sequentially arranged from bottom to top. Further comprising: an alloy layer; The alloy layer is arranged between the TaN intermediate layer and the perovskite cell. The material of the alloy layer comprises one of a Ta-Ni alloy mixture, a Ta-Ti alloy mixture and a Ta-Cu alloy mixture; and the thickness of the alloy layer is 1-2 nm. The perovskite cell is a p-i-n type perovskite cell. The p-i-n type perovskite cell comprises a hole transport layer, a perovskite light absorption layer, an electron transport layer, a buffer layer and a transparent electrode layer, which are sequentially arranged from bottom to top. The electron selection layer in the silicon bottom cell is arranged upward. The hole transport layer of the p-i-n type perovskite cell is arranged close to the electron selection layer of the silicon bottom cell.

2. A perovskite silicon tandem cell employing a TaN interlayer, characterized in that, The bottom electrode, the silicon bottom cell, the TaN intermediate layer, the perovskite cell and the metal grid electrode are sequentially arranged from bottom to top. Further comprising: an alloy layer; the alloy layer is arranged between the TaN intermediate layer and the perovskite cell. The perovskite cell is an n-i-p type perovskite cell. The n-i-p type perovskite cell comprises an electron transport layer, a perovskite light absorption layer, a hole transport layer, a buffer layer and a transparent electrode layer, which are sequentially arranged from bottom to top. The hole selection layer in the silicon bottom cell is arranged upward. The electron transport layer of the n-i-p type perovskite cell is arranged close to the hole selection layer of the silicon bottom cell.

3. The perovskite silicon tandem cell employing a TaN intermediate layer according to claim 1 or 2, characterized in that, The silicon bottom cell comprises one of an HJT cell, a TOPCon cell and a PERC cell.

4. A method for producing the perovskite silicon tandem cell using a TaN intermediate layer according to claim 1 or 2, characterized by, The method comprises the following steps: Preparation of a TaN intermediate layer on the upper surface of a silicon bottom cell; Preparation of a perovskite cell on the upper surface of the TaN intermediate layer; Preparation of a metal grid electrode on the upper surface of the perovskite cell; and preparation of a bottom electrode on the lower surface of the silicon bottom cell.

5. The method of claim 4, wherein the method is characterized by: Preparation of a TaN intermediate layer on the upper surface of a silicon bottom cell comprises: Using a reactive magnetron sputtering technology, a TaN with a thickness of 1-5 nm is prepared on the upper surface of the silicon bottom cell to form a TaN intermediate layer.

Images