A method for preparing a high-transparency solar photovoltaic device

Abstract

The present invention relates to the technical field of solar cells, and specifically to a method for preparing a high-transparency solar cell device. The problem of limited photoelectric conversion efficiency due to controlled absorption of visible light in current transparent solar cells is solved. The present invention provides a method for preparing a high-transparency solar cell device, which uses a transparent top electrode with an AVT greater than 85% and an active layer material with near-infrared absorption capability to prepare a high-transparency device under the joint action, and can achieve the adjustment of the AVT of the device from 30% to more than 85%, ensuring that while improving the AVT, the photoelectric conversion performance of the device remains at a good level.

Description

Technical Field

[0001] The invention relates to the technical field of solar cells, in particular to a method for preparing a high-transparency solar photovoltaic device. Background Art

[0002] Photovoltaic technology has achieved rapid development in recent years, and photovoltaic power generation has gradually become a common energy supply mode in many countries and regions. Compared with opaque photovoltaic technology, transparent photovoltaic technology can not only convert solar energy into electrical energy, but also provide a natural visible light environment, providing a unique way to utilize solar energy. The high transparency property enables transparent photovoltaic devices (TPV) to be widely used in building or car windows, greenhouses, smart devices and other occasions. When the average visible light transmittance (AVT) reaches more than 70%, TPV will meet the transmittance requirements for use on office or living room windows. Some special applications also need to be used under highly transparent conditions, such as invisible self-powered wearable devices. At the same time, the high photoelectric conversion efficiency of TPV provides great potential for using TPV as an energy source for high-energy consumption applications.

[0003] Because improving the device's AVT requires limiting the collection of visible light in the solar spectrum to a very limited level, the device will absorb less light in the visible light region, resulting in a significant reduction in photoelectric conversion performance. In order to meet more application needs, exploring high-transparency photovoltaic devices and further improving device performance are research focuses. Therefore, it is necessary to explore the selection and use of light-absorbing materials, transparent electrodes, and device structures. In addition, due to the low output power of small-area devices prepared in the laboratory (including limited open-circuit voltage and low short-circuit current density, etc.), it is difficult to be widely used in real situations. Therefore, practical applications require the exploration of TPV devices with greater output power. Summary of the invention

[0004] In view of the problem that the current transparent solar cells have limited photoelectric conversion efficiency due to the control of the absorption of visible light, the present invention provides a method for preparing a high-transparency solar cell device, using a transparent top electrode with an AVT greater than 85% and an active layer material with infrared absorption capability, and preparing a high-transparency solar cell by adjusting the ratio of the light-absorbing layer to the acceptor and the thickness of the light-absorbing layer film. The AVT of the TPV device can be adjusted arbitrarily within the range of 40% to 85%, ensuring that the photoelectric conversion performance of the device remains at a good level while the AVT is improved.

[0005] To achieve the above purpose, the technical solution adopted by the present invention is as follows:

[0006] A method for preparing a high-transparency solar device, wherein the solar device structure is a transparent electrode, a hole transport layer, an active light absorbing layer, an electron transport layer and a transparent electrode in sequence, characterized in that the preparation method comprises:

[0007] S1, washing and drying the ITO glass substrate with a surfactant, deionized water and isoethanol ultrasonically in sequence to form a transparent bottom electrode;

[0008] S2, diluting PEDOT (4083) with deionized water or ethanol to prepare a PEDOT (4083) solution, and spin-coating the PEDOT (4083) solution on an ITO substrate to form a hole transport layer;

[0009] S3, dissolving the active layer material PTB7-Th:IEICO-4F, the specific combination, in a chlorobenzene solvent at a mass ratio of 1:1, 1:2, 1:3, 1:4, 1:5, 1:10, and adding CN solvent to adjust the morphology, changing the thickness of the active layer by precisely controlling the specific ratio and overall concentration of the donor and the acceptor at the same time, and spin coating it on the hole transport layer to form an active light absorbing layer;

[0010] S4, spin coating a solution of ZnO nanoparticles on the active light absorbing layer to form an electron transport layer;

[0011] S5, using water-based and ethanol-based Ag NWs to be spin-coated on the electron transport layer multiple times in different proportions, controlling the nanowire density and interlayer contact resistance, and forming the final transparent electrode by spectral adjustment;

[0012] S6. Use ultrafast laser to pattern-etch the spin coating layer formed in S1-S5 to complete the preparation of the solar device.

[0013] The transparent electrode is one or more of a thin metal film, a metal oxide, a conductive polymer, a metal nanowire, a carbon nanotube, and graphene.

[0014] The active layer material is one of Y6 and DPP2T or a mixture of the two.

[0015] The hole transport layer material is PEDOT, CuO x , WO 3 、MoO 3 、NiO x , CuI, CuPc, ZnPc, PTAA, Alq 3 , CuSCN, Spiro-OMeTAD or one or more thereof are mixed and used.

[0016] The electron transport layer material is ZnO, TiO 2 ,MgO,Nb 2 O 5 、Nd2 O 3 SnO 2 , WO 3 、ZrO 2 , ZnS, ZnSe, PDINO, PEIE, PFN-Br, PFSO 3 One or more of Na, PFN / PFBT are used in combination.

[0017] In the device structure, the positions of the hole transport layer and the electron transport layer can be interchanged.

[0018] When the solar device is prepared on a large scale, it is necessary to process the bottom transparent electrode, the electron transport layer and the top transparent electrode using a laser patterning method to form a series-parallel structure.

[0019] The beneficial effects of the present invention are as follows: the combination of active layer materials and transparent electrodes is designed in the present invention, so that the AVT of the device can be arbitrarily adjusted within the range of 40% to 85%, ensuring that while improving the AVT, the photoelectric conversion performance of the device remains at a good level. The selected active layer material combination not only specifically reduces the absorption of the device in the visible light region, but also can exert the photoelectric conversion performance in other spectral regions. The designed electrode has high transparency and can be prepared at room temperature. The preparation process is simple, has good repeatability and is easy to prepare large-area devices. In addition, by designing the device in series and parallel and using the laser etching patterning method, a large-area, high-transparency and high-efficiency TPV module can be prepared.

[0020] Using the designed device structure, the PCE of the prepared solar cell device can reach 3.8% when the AVT of the device is greater than 70%, 3.5% when the AVT of the device is greater than 75%, and 1.6% when the AVT of the device is greater than 80%. 2 When the AVT of TPV device is greater than 80%, the PCE can exceed 1.3%. The device performance obtained is at a very high level in the current research field. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is the absorption spectrum of different active layer materials.

[0022] Figure 2 It is the film transmittance spectrum of different donor-acceptor ratios at the same total active layer concentration.

[0023] Figure 3 It is the transmittance spectrum of the film with different total concentration of active layer at the same donor-acceptor ratio.

[0024] Figure 4It is the AVT statistical spectrum of thin films under different donor-acceptor ratios and different active layer concentrations.

[0025] Figure 5 It is the statistical spectrum of CRI of thin films under different donor-acceptor ratios and different active layer concentrations.

[0026] Figure 6 These are the AVT statistical spectra of TPV devices with different donor-acceptor ratios and different active layer concentrations and electrodes being Ag NWs.

[0027] Figure 7 It is the AVT statistical spectrum of TPV devices with different donor-acceptor ratios and different active layer concentrations and the electrode is PH1000.

[0028] Figure 8 This is the PCE statistical spectrum of TPV devices with Ag NWs as electrodes at different donor-acceptor ratios and different active layer concentrations.

[0029] Fig. 9 This is the PCE statistical spectrum of TPV devices with different donor-acceptor ratios and different active layer concentrations and the electrode is PH1000.

[0030] Fig.10 The active area is about 10.3cm 2 Current density-voltage curve of TPV device.

[0031] Fig.11 It is a patterning design for laser processing of Ag NWs in small area devices.

[0032] Fig.12 It is a series design in large area devices.

[0033] Fig.13 It is a schematic cross-sectional view of the laser cutting lines of P1, P2, and P3 of large-area devices. DETAILED DESCRIPTION

[0034] The technical solution of the present invention is further described below with reference to the accompanying drawings and through specific embodiments:

[0035] The present invention is explained below in conjunction with specific embodiments.

[0036] The preparation method of the present invention is:

[0037] 1. The ITO glass substrate was ultrasonically washed with surfactant, deionized water and isoethanol in turn for 10 minutes each. It was then dried and used.

[0038] 2. Disperse PEDOT (4083) in deionized water or ethanol to prepare a PEDOT (4083) solution, and spin-coat it on the ITO substrate at 4000 rpm for 25 seconds, anneal at about 100°C for 5 minutes, and cool to room temperature.

[0039] 3. Dissolve the donor PTB7-Th and the acceptor IEICO-4F of the active layer material in chlorobenzene solvent, and add additives such as CN or DIO. The concentration can be 5-40mg / mL. Spin coating at 2000rpm for 40-60s, annealing at about 100℃ for 10 minutes. The donor and acceptor of the active layer material can be adjusted according to 1:1-1:20, 40-5mg / ml, such as Figure 2 and Figure 3 As shown, active layer films with different absorption spectra and thicknesses of 10-200 nm are prepared to adjust AVT and CRI over a wide range.

[0040] 4. After cooling, spin-coat the ZnO nanoparticle solution on the substrate at 4000 rpm for 20-50 seconds.

[0041] 5. Disperse Ag NWs in ethanol or water solution to prepare dispersions of different concentrations. You can use Ag NWs in the same solvent or Ag NWs mixed with different solvents, such as mixing water-based and ethanol-based Ag NWs in different proportions and concentrations and spin coating them on the ZnO thin film substrate. According to the required device active area, input the designed pattern into the computer, such as Fig.11 As shown, ultrafast laser is used for patterning etching, wherein the laser focus position is adjusted to 20.3 cm 2 , speed 1000mm / s, power 15%, frequency 80Hz. After Ag NWs etching is completed, the preparation of small area TPV device is completed.

[0042] For the preparation of large area devices:

[0043] 1. Preparation of large-area devices and their series design. After the ITO substrate is cleaned, enter Fig.12 In the P1 pattern, adjust the laser focus position to 20.3cm 2 , speed 400 mm / s, power 35%, frequency 20 Hz. Etch the ITO layer.

[0044] 2. Spin-coat the PEDOT solution at 4000 rpm for 25 seconds, anneal at about 100°C for 5 minutes, and cool to room temperature.

[0045] 3. Spin-coat the active layer solution, such as the active layer spin-coating method of the small-area battery mentioned above, spin-coat at 2000rpm for 40-60s, and anneal at about 100℃ for 10 minutes.

[0046] 4. Spin-coat the ZnO nanoparticle solution on the substrate at 4000 rpm for 20-50 seconds. Enter Fig.12 For the P2 pattern, adjust the laser focus position to 20.3 cm 2 , speed is 1000mm / s, power is 15%, and frequency is 20Hz.

[0047] 5. Spin-coat the Ag NWs solution. You can spin-coat multiple times. Enter Fig.12 In the middle P3 pattern, the P3 layer adjusts the laser focus position to 20.3cm 2 , speed 1000mm / s, power 20%, frequency 80Hz. Laser patterning is performed to construct the required active area, and multiple devices can be connected in series. The specific design pattern is as follows Fig.12 As shown. (The corresponding parameters of lasers in different instruments may be different). Finally, an active area of ​​10.3 cm 2 The high transparency TPV device has an AVT of over 80%.

[0048] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above and that the present invention can be implemented in other specific forms without departing from the spirit or essential features of the present invention. Therefore, the embodiments should be considered exemplary and non-restrictive in all respects, and the scope of the present invention is defined by the appended claims rather than the above description, and it is intended that all changes falling within the meaning and scope of the equivalent elements of the claims be included in the present invention.

[0049] In addition, it should be understood that although the present specification is described according to implementation modes, not every implementation mode contains only one independent technical solution. This description of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment may also be appropriately combined to form other implementation modes that can be understood by those skilled in the art.

Claims

1. A method for preparing a high-transparency solar device, wherein the solar device structure is a transparent electrode, a hole transport layer, an active light absorbing layer, an electron transport layer and a transparent electrode, characterized in that: The preparation method comprises: S1, washing and drying the ITO glass substrate with a surfactant, deionized water and isoethanol ultrasonically in sequence to form a transparent bottom electrode; S2, diluting PEDOT (4083) with deionized water or ethanol to prepare a PEDOT (4083) solution, and spin-coating the PEDOT (4083) solution on an ITO substrate to form a hole transport layer; S3, dissolving the active layer material PTB7-Th:IEICO-4F, the specific combination, in a chlorobenzene solvent at a mass ratio of 1:1 to 1:5, and adding CN solvent to adjust the morphology, changing the thickness of the active layer by precisely controlling the specific ratio and overall concentration of the donor and the acceptor at the same time, and spin coating it on the hole transport layer to form an active light absorbing layer, wherein the overall concentration is 10 to 20 mg / ml; S4, spin coating a solution of ZnO nanoparticles on the active light absorbing layer to form an electron transport layer; S5, using water-based and ethanol-based Ag NWs to be spin-coated on the electron transport layer multiple times in different proportions, controlling the nanowire density and interlayer contact resistance, and forming the final transparent electrode by spectral adjustment; S6. Use ultrafast laser to pattern-etch the spin coating layer formed in S1-S5 to complete the preparation of the solar device.

2. The method for preparing a high-transparency solar device according to claim 1, characterized in that: In the device structure, the positions of the hole transport layer and the electron transport layer can be interchanged.

3. The method for preparing a high-transparency solar device according to claim 1, characterized in that: When the solar device is prepared on a large scale, it is necessary to process the bottom transparent electrode, the electron transport layer and the top transparent electrode using a laser patterning method to form a series-parallel structure.

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