Semitransparent organic photovoltaic cell device and preparation method thereof

Abstract

The invention relates to a semitransparent organic photovoltaic cell device and a preparation method thereof. The semitransparent organic photovoltaic cell device sequentially comprises a substrate, a first electrode layer, a functional layer and a second electrode layer from bottom to top. The second electrode layer is further composed of an electrode buffer layer and a transparent electrode layer, and through thickness and material selection of the electrode buffer layer and the transparent electrode layer, light transmission and conductivity balance of the cell are ensured. The invention develops a novel electrode structure based on a semitransparent organic photovoltaic cell device and a preparation process, and is used for improving the stability, the photoelectric conversion efficiency, the light transmittance and the color adjustability of the semitransparent organic photovoltaic cell device.

Description

Technical Field

[0001] The invention relates to the field of organic photoelectric semiconductor devices, and in particular to a semi-transparent organic photovoltaic cell device and a preparation method thereof. Background Art

[0002] Compared with traditional solar cells such as silicon, CdTe, and gallium arsenide, organic photovoltaic cells have attracted extensive attention and research from researchers due to their many differentiated characteristics, such as light weight, flexibility, solution processing, and easy adjustment of the active layer material structure. In recent years, with the iteration of non-fullerene acceptor materials, the performance of organic photovoltaic cells has developed rapidly. The efficiency of opaque devices represented by the Y series acceptors has exceeded 20%, achieving rapid development.

[0003] Compared with opaque organic photovoltaic cell devices, semi-transparent organic photovoltaic cell (ST-OPVs) devices have multiple functions such as power generation and light transmission, and show great application potential in the fields of indoor photovoltaics, photovoltaic building integration, photovoltaic agriculture and wearable electronic devices. At present, based on new materials, multi-components, additive strategies and new process methods, the photoelectric conversion efficiency of ST-OPV cells has been greatly improved. However, the efficiency and stability of its cells still face the problem of rapid attenuation. Its efficiency attenuation is mainly due to the phase separation change of the active layer morphology from metastable to stable state and the degradation behavior of the electrode. In particular, the efficiency of semi-transparent cells using ultra-thin metal electrodes decays more rapidly, which is a key bottleneck hindering its development and application.

[0004] Indium tin oxide (ITO) is an excellent transparent conductive oxide with good light transmittance and high conductivity. However, ITO must be prepared by sputtering process, which easily damages the organic layer and is not conducive to the preparation of ST-OPVs.

[0005] Therefore, it is necessary to develop new electrode structures and preparation methods, which is of great significance for the development of stable and efficient semi-transparent organic photovoltaic cells. Summary of the invention

[0006] The purpose of the present invention is to provide a novel electrode structure based on a semi-transparent organic photovoltaic cell device and a preparation method thereof, so as to improve the stability, photoelectric conversion efficiency, transmittance and color adjustability of the semi-transparent organic photovoltaic cell.

[0007] To achieve the purpose of the present invention, the technical solution is as follows:

[0008] A semi-transparent organic photovoltaic cell device comprises a substrate, a first electrode layer, a functional layer and a second electrode layer stacked in sequence from bottom to top, wherein the second electrode layer comprises an electrode buffer layer and a transparent electrode layer, the electrode buffer layer is located between the functional layer and the transparent electrode layer, the electrode buffer layer material is selected from metal or metal alloy, and the electrode buffer layer thickness is selected from 7-30nm.

[0009] Furthermore, the transparent electrode layer is selected from a conductive metal oxide layer, or a composite conductive layer comprising a conductive metal oxide layer and a metal layer.

[0010] In one embodiment, the composite conductive layer including a conductive metal oxide layer and a metal layer is selected from a conductive metal oxide layer, a metal layer, and a conductive metal oxide layer stacked sequentially from bottom to top.

[0011] In one embodiment, the thickness of the electrode buffer layer is selected from 7-20 nm.

[0012] Furthermore, the thickness of the electrode buffer layer is selected from 7-15 nm.

[0013] Furthermore, the thickness of the electrode buffer layer is selected from 10-12 nm.

[0014] It should be noted that controlling the thickness of the electrode buffer layer within 7-30 nm helps optimize the light transmittance of the battery. Too thick will reduce light transmittance, while too thin may lead to insufficient conductivity.

[0015] In one embodiment, the electrode buffer layer material is selected from silver (Ag), aluminum (Al), gold (Au), copper (Cu), magnesium (Mg), cadmium (Cr), or alloys of the above metals.

[0016] Furthermore, the electrode buffer layer material is selected from silver (Ag), aluminum (Al), gold (Au), or alloys of the above metals.

[0017] In a specific embodiment, the electrode buffer layer material is silver.

[0018] In the present invention, the electrode buffer layer is selected from an ultra-thin metal layer. The reason for the existence of the ultra-thin metal layer is that the transparent electrode layer needs to be prepared by a sputtering process. The temperature and energy are high during the sputtering process. If the transparent electrode layer is in direct contact with the functional layer, the impact of the high-energy metal oxide particles and the heat generated will damage the functional layer below it, resulting in the deterioration of the device performance. The present invention introduces an ultra-thin metal layer as an electrode buffer layer. On the one hand, it can effectively protect the functional layer when the transparent electrode layer is sputtered. On the other hand, it can adjust the transparency of the device by adjusting the thickness of the electrode buffer layer and the transparent electrode layer, so that the device has a good transparency effect while maintaining a high efficiency, and presents different colors.

[0019] The electrode buffer layer described in this application needs to form a certain continuous thin film layer to effectively play a protective role, and only an appropriate thickness can achieve the effect. If the electrode buffer layer is too thin (such as a seed layer), since the metal layer usually forms an island structure, a large area of ​​the active layer is still exposed, and thus it cannot effectively play a protective role.

[0020] In one embodiment, the transparent electrode layer material is selected from indium oxide, zinc oxide, tin oxide, indium tin oxide (ITO), fluorine-doped tin oxide (FTO), gallium-doped zinc oxide (GZO), aluminum-doped zinc oxide (AZO), indium zinc oxide (IZO), indium gallium zinc oxide (IGZO), ITO / Ag / ITO, or ITO / Cu / ITO, etc.

[0021] Preferably, the transparent electrode layer material is selected from indium tin oxide (ITO) or ITO / Ag / ITO.

[0022] It should be noted that in the present invention, "conductive metal oxide layer / metal layer / conductive metal oxide layer" means a conductive metal oxide layer, a metal layer and a conductive metal oxide layer stacked in sequence from bottom to top. That is, the ITO / Ag / ITO means an ITO layer, an Ag layer and an ITO layer stacked in sequence from bottom to top. The same is true for ITO / Cu / ITO.

[0023] In order to ensure the transparency of the semi-transparent organic photovoltaic cell device, when the transparent electrode layer in the second electrode layer is selected from the composite conductive electrode layer, the thickness of the metal layer is preferably 1-30nm; further, the thickness of the metal layer is preferably 1-20nm. The thickness can be adjusted according to the actual performance requirements of the device.

[0024] In one embodiment, the thickness of the transparent electrode layer is selected from 30-200 nm. Further, the thickness of the transparent electrode layer is selected from 50-200 nm. More preferably, the thickness of the transparent electrode layer is selected from 100-200 nm.

[0025] The advantages of the transparent electrode layer of the present invention being selected from a conductive metal oxide layer or a composite conductive layer containing the same are: 1. It has good light transmittance and high conductivity; 2. It has good chemical stability, a matching energy band structure, and a mature mass production process.

[0026] In a preferred embodiment, the electrode buffer layer material is selected from silver, and the transparent electrode layer material is selected from indium tin oxide (ITO).

[0027] In one embodiment, the second electrode layer consists of an electrode buffer layer and a transparent electrode layer.

[0028] In one embodiment, the substrate is selected from a light-transmitting substrate. Further, the substrate is selected from a light-transmitting plastic or a light-transmitting glass.

[0029] In one embodiment, the substrate is selected from a glass substrate, a thin film glass substrate or a transparent plastic substrate. The transparent plastic substrate may include a single-layer or multi-layer film such as polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polyetheretherketone (PEEK) and polyimide (PI), but is not limited thereto.

[0030] In one embodiment, the first electrode layer may be made of a transparent or translucent conductive material, but is not limited thereto. The conductive material may be a conductive metal oxide, such as indium oxide, zinc oxide, tin oxide, indium tin oxide (ITO), fluorine-doped tin oxide (FTO), gallium-doped zinc oxide (GZO), aluminum-doped zinc oxide (AZO), indium zinc oxide (IZO) and indium gallium zinc oxide (IGZO); a conductive polymer, such as poly (3,4-ethylenedioxythiophene) / poly (4-styrene sulfonate) (PEDOT / PSS), polypyrrole and polyaniline, etc.; a conductive carbon material, such as graphene, carbon nanotubes, etc.; a nano-conductive material, such as metal nanoparticles or nanowires, etc.; an ultra-thin metal layer capable of maintaining a certain transmittance and a composite stack containing the same, such as a metal layer formed of a metal such as gold, platinum, silver, copper, cobalt, nickel, indium or aluminum or a film stack containing an alloy of any of these metals.

[0031] Preferably, the first electrode layer is selected from ITO.

[0032] In one embodiment, the functional layer comprises a first charge transport layer, a photoactive layer and a second charge transport layer; the first charge transport layer is located between the first electrode layer and the photoactive layer, and the second charge transport layer is located between the second electrode layer and the photoactive layer.

[0033] The first charge transport layer and the second charge transport layer are used in pairs, that is, if the first charge transport layer is an anode buffer layer, the second charge transport layer is a cathode buffer layer; on the contrary, if the first charge transport layer is a cathode buffer layer, the second charge transport layer is an anode buffer layer. The function of the charge transport layer is to effectively and selectively transfer the electrons and holes separated from the photoactive layer to the corresponding electrode. Among them, the cathode buffer layer can efficiently transfer electrons to the cathode, and its material can be a metal oxide with a low work function, a fullerene derivative, a polymer or a composite thereof, such as titanium oxide (TiO x )、ZnO、SnO 2 )、polyethoxyethyleneimine (PEIE), polyetherimide (PEI), PFN, PFN-Br, PDINN, PDINO, PNDIT-F 3N-Br、PNDIT-F 3 N and ZnO-PEIE composites, PEI-Zn, ZnO-PEI composites, etc., but not limited thereto. The anode buffer layer can efficiently transport holes to the anode, and its material can be a metal oxide with a high work function such as molybdenum oxide (MoO x ), vanadium oxide (V 2 O 5 ), nickel oxide (NiO), tungsten oxide (WO x ), or PEDOT:PSS and molecular self-assembled materials such as 2PACz, MeO-2PACz, etc., but not limited thereto.

[0034] The photoactive layer comprises a photoactive layer donor material and a photoactive layer acceptor material. The photoactive layer donor material is preferably selected from a polymer donor material. Specifically, it can be selected from a polythiophene material system, such as P3AT, P3HT, P3OT, P3DDT, etc.; a fluorene-containing polymer material system, such as PF8BT, etc.; a novel structure narrow bandgap polymer material system, such as benzothiadiazoles (BT, DBT), quinoxalines (QU, PQ), pyrazines (TP, PQ) and electron-rich groups (such as thiophene derivatives) copolymerized, such as PCDTBT, PCPDTBT, PFO-DBT, PTB7, PM6, J52, etc.

[0035] In a specific embodiment, the photoactive layer donor material is selected from one, two or more of PBDB-T, PM6, PM7, D18, D18-Cl, PTO2, PB2, PB2F, PTVT-BT, PTQ10, PTQ11, PBQx-TCl, PQM-Cl, J106, and J52-Cl, but is not limited thereto.

[0036] The photoactive layer acceptor material is preferably selected from non-fullerene acceptor materials or fullerene derivative acceptor materials. Preferably, the photoactive layer acceptor material is selected from Y6, L8-BO, H2, N3, BTP-eC9, PY-IT, PTBPT, PC61BM ([6,6]-phenyl C61 butyric acid methyl ester), PC71BM ([6,6]-phenyl C71 butyric acid methyl ester), indene-containing fullerene, etc., but not limited thereto.

[0037] In one embodiment, the mass ratio of the photoactive layer donor material to the photoactive layer acceptor material in the photoactive layer is selected from 0.8:1.5-1.5:0.8; further, selected from 1:1-1:1.5; further, selected from 1:1-1:1.3.

[0038] The thickness of the photoactive layer is preferably 50-500 nm, and more preferably 100-200 nm.

[0039] The thickness of the first charge transport layer is preferably 1-200 nm, and more preferably 1-100 nm.

[0040] The thickness of the second charge transport layer is preferably 1-200 nm, and more preferably 1-100 nm.

[0041] The photoactive layer may be prepared by dissolving the photoactive material in an organic solvent and then coating the resulting solution by methods such as spin coating, dip coating, screen printing, gravure printing, spray coating, doctor blade, slit coating, and inkjet printing, but is not limited thereto.

[0042] In one embodiment, the first electrode layer is an anode layer, and the second electrode layer is a cathode layer.

[0043] In another embodiment, the first electrode layer is a cathode layer, and the second electrode layer is an anode layer.

[0044] In one embodiment, the semi-transparent organic photovoltaic cell device according to the present invention comprises a substrate, an anode layer, an anode buffer layer, a photoactive layer, a cathode buffer layer and a cathode layer stacked in sequence from bottom to top.

[0045] In another embodiment, the semi-transparent organic photovoltaic cell device according to the present invention comprises a substrate, a cathode layer, a cathode buffer layer, a photoactive layer, an anode buffer layer and an anode layer stacked in sequence from bottom to top.

[0046] Furthermore, the semi-transparent organic photovoltaic cell device according to the present invention further comprises an encapsulation layer, wherein the encapsulation layer comprises a sealant layer and an upper cover plate. The upper cover plate is located on the upper part of the second electrode layer, and the sealant layer is located on the edges of the substrate and the upper cover plate to form an edge encapsulation for the semi-transparent organic photovoltaic cell. Alternatively, the sealant layer is located on the upper part of the substrate and the second electrode layer, and the semi-transparent organic photovoltaic cell is encapsulated on the entire surface in combination with the upper cover plate, and the upper cover plate is located on the upper part of the sealant layer.

[0047] In one embodiment, the sealant layer material can be selected from sealant or a sealant film.

[0048] In a specific embodiment, the material of the sealant layer is selected from silicone, butyl glue, epoxy resin, acrylic resin, UV curing glue or AB component glue, but is not limited thereto.

[0049] The upper cover plate can be selected from materials with excellent transparency, surface smoothness, ease of operation and waterproofness. Specifically, glass packaging can be used, and flexible packaging such as polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polyetheretherketone (PEEK), polyimide (PI), polyacrylate (PA), polycarbonate (PC), polyethylene (PE), polypropylene (PP), polyvinyl chloride (PVC) and thermoplastic polyurethane (TPU) can also be used, but not limited thereto.

[0050] The semi-transparent organic photovoltaic cell device according to the present invention comprises one or more organic photovoltaic cell units. When the semi-transparent organic photovoltaic cell device comprises multiple organic photovoltaic cell units, the multiple organic photovoltaic cell units are connected in series or in parallel.

[0051] In a specific embodiment, the semi-transparent organic photovoltaic cell device comprises 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12 or more organic photovoltaic cell units.

[0052] The working principle of the semi-transparent organic photovoltaic cell device according to the present invention is as follows:

[0053] After absorbing photons, the donor material and the acceptor material of the photoactive layer form electron-hole pairs with certain binding energy, namely, photogenerated excitons. Then, driven by the exciton concentration gradient, the photogenerated excitons diffuse to the interface between the donor and the acceptor and are converted into CT state excitons with weaker binding energy. Driven by the energy level difference, the CT state excitons overcome the binding energy and dissociate into carriers. The separated electrons and holes become freely movable carriers. Among them, electrons move toward the cathode in the acceptor material, and holes move toward the anode in the donor material. The cathode and the anode capture the electrons and holes that move to the vicinity of the electrodes and output charges to the outside, thereby realizing power supply.

[0054] Furthermore, the present invention also relates to a method for preparing the above-mentioned semi-transparent organic photovoltaic cell device, comprising the following steps:

[0055] S1: providing a substrate;

[0056] S2: preparing a first electrode layer on a substrate;

[0057] S3: preparing a functional layer on the first electrode layer;

[0058] S4: preparing a second electrode layer on the functional layer;

[0059] S5: Packaging.

[0060] Wherein: the second electrode layer includes an electrode buffer layer and a transparent electrode layer. In step S4, the electrode buffer layer is first prepared on the functional layer by vacuum evaporation; and then the transparent electrode layer is prepared on the electrode buffer layer by sputtering.

[0061] The electrode buffer layer material is selected from metal or metal alloy, and the electrode buffer layer thickness is selected from 7-30 nm.

[0062] In one embodiment, the sputtering process is performed under vacuum conditions, and the sputtering temperature is selected from 25-150° C. Preferably, the sputtering temperature is selected from 25-100° C., and more preferably, the temperature is selected from 25-50° C.

[0063] Furthermore, in vacuum evaporation, the vacuum conditions are: using inert gas protection, the inert gas is selected from argon, and the vacuum degree is 1*10 -6 mbar~2*10 -6 millibar.

[0064] Furthermore, the deposition power of the sputtering process is 1-2 KW; preferably, the deposition power of the sputtering process is 1-1.2 KW.

[0065] Furthermore, the sputtering rate of the sputtering process is 0.3-0.5Å / s; preferably, the sputtering rate of the sputtering process is 0.4-0.5Å / s.

[0066] The specific steps of step S4 are: under vacuum conditions, the transparent electrode material deposition power is set to 1-2KW, the sputtering rate is set to 0.3-0.5 Å / s, and before depositing the transparent electrode layer on the electrode buffer layer, the target material is pre-sputtered to remove possible impurities, and then the transparent electrode layer is deposited at a temperature of 25-150°C.

[0067] In one embodiment, the first electrode layer can be prepared on the substrate by sputtering, electron beam deposition, vacuum evaporation, spin coating, inkjet printing, spraying, blade coating, slit coating, etc., but is not limited to the above methods.

[0068] In one embodiment, the functional layer can be prepared on the substrate by vacuum evaporation, spin coating, inkjet printing, spray coating, blade coating, slit coating, etc., but is not limited to the above methods.

[0069] Furthermore, the functional layer further comprises a first charge transport layer, a photoactive layer and a second charge transport layer, and step S3 further comprises the following steps:

[0070] S31: preparing a first charge transport layer on the first electrode layer;

[0071] S32: preparing a photoactive layer on the first charge transport layer;

[0072] S33: preparing a second charge transport layer on the photoactive layer.

[0073] Preferably, the photoactive layer is prepared by a solution method such as spin coating, inkjet printing, slit coating, screen printing or doctor blade coating. The solution method has the advantages of large area, flexibility, transparency and obvious low cost.

[0074] In one embodiment, the packaging process S5 includes a sealant layer and an upper cover plate, and the specific preparation steps are as follows:

[0075] In step S4, sealant is coated around the edge or the entire surface of the device with a transparent electrode layer, or a sealant film is applied to form a sealant layer; the upper cover plate is placed on the sealant layer and laminated or rolled. During or after the lamination or rolling process, the battery is encapsulated by heating or ultraviolet light curing.

[0076] Alternatively, a sealant is coated around the edges or on the entire surface of the upper cover plate, or a sealant film is applied; the upper cover plate covered with the sealant or film is placed on the transparent electrode layer of the device prepared in step S4, and laminated or rolled; during or after the lamination or rolling process, the battery is encapsulated by heating or ultraviolet light curing.

[0077] When the semi-transparent organic photovoltaic cell device of the present invention is a module, that is, comprising a plurality of organic photovoltaic cell units, the preparation method further comprises a laser process, and the plurality of organic photovoltaic cell units are connected by the laser process, such as etching the insulating channel P1, the connecting channel P2 and the isolating channel P3 by the laser process.

[0078] The semi-transparent organic photovoltaic cell described in the present invention can be applied to wearable devices, smart Internet of Things, smart homes, smart agriculture, building photovoltaics, vehicle-mounted photovoltaics and other fields.

[0079] Compared with the prior art, the present invention has the following significant advantages: the second electrode layer provided by the present application has good stability and high conductivity, and the light transmittance is adjustable, so that the prepared device has a high photoelectric conversion efficiency and can present different colors. In addition, the materials used in the second electrode layer are all mature materials, and have mature mass production processes, which are more suitable for industrial preparation. BRIEF DESCRIPTION OF THE DRAWINGS

[0080] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For those skilled in the art, other drawings can be obtained based on these drawings without paying any creative work.

[0081] Figure 1 It is a schematic diagram of the structure of the semi-transparent organic photovoltaic cell device of device embodiments 1-6 of the present application.

[0082] Figure 2 It is a partial structural cross-sectional view of the semi-transparent organic photovoltaic cell of device embodiments 7-10 of the present application.

[0083] Figure 3 This is a physical picture of the device in embodiment 7 of the present application.

[0084] Figure 4 This is a physical picture of the device in embodiment 8 of the present application.

[0085] Figure 5 This is a physical picture of the device in embodiment 9 of the present application.

[0086] Figure 6 This is a physical picture of the device in embodiment 10 of the present application.

[0087] Wherein: 10-substrate, 11-first electrode layer, 12-functional layer, 121-first charge transport layer, 122-photoactive layer, 123-second charge transport layer, 13-second electrode layer, 131-electrode buffer layer, 132-transparent electrode layer, 14-sealing layer, 15-upper cover layer, P1-insulating channel, P2-connecting channel, P3-isolating channel DETAILED DESCRIPTION

[0088] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0089] It should be noted that all directional indications in the embodiments of the present application (such as up, down, left, right, front, back, inside, outside...) are only used to explain the relative position relationship between the components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0090] In this application, the descriptions of "first", "second", etc. are only used for descriptive purposes, and do not specifically refer to the order or sequence, nor are they used to limit this application. They are only used to distinguish components or operations described with the same technical terms, and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" or "second" may explicitly or implicitly include at least one of the features.

[0091] In the present application, the function of the semi-transparent organic photovoltaic cell can be achieved by combining the various layers described above, or some layers can be completely omitted, and it can also include other layers not explicitly described. In each layer, a single material or a mixture of multiple materials can be used to achieve optimal performance.

[0092] In the present application, the technical features described in an open manner include closed technical solutions composed of the listed features, and also include open technical solutions containing the listed features.

[0093] Semi-transparent organic photovoltaic cell device preparation

[0094] Device Example 1:

[0095] like Figure 1 As shown, the semi-transparent organic photovoltaic cell device structure: substrate / ITO / PEI-Zn / PM6:L8-BO / MoO 3 / Ag / ITO, device area: 0.092cm 2 .

[0096] The preparation method comprises the following steps:

[0097] 1) ITO conductive glass cleaning (the substrate glass 10 has an ITO layer 11 formed thereon)

[0098] The ITO conductive glass was cleaned with detergent, rinsed, and then ultrasonically cleaned with deionized water, acetone, and isopropanol for 15 minutes, then blown dry with nitrogen and treated in a plasma cleaner for 5 minutes to further clean the surface and improve wettability.

[0099] 2) Preparation of the first charge transport layer (cathode buffer layer) 121

[0100] The PEI-Zn solution was evenly spin-coated on the ITO in air at a spin-coating speed of 1500 rpm for 30 seconds, and dried at 150° C. for 10 minutes to obtain a cathode buffer layer.

[0101] 3) Preparation of photoactive layer 122

[0102] In a glove box (inert gas atmosphere), the photoactive layer material solvent is evenly spin-coated on the first charge transport layer at a rotation speed of 1800-4000 rpm to obtain a photoactive layer with a total thickness of about 100 nm.

[0103] The active layer material preparation method is: dissolving the donor material and the acceptor material in toluene, with a total concentration of 17.6 mg / mL, wherein the donor material is selected from PM6, the acceptor material is selected from L8-BO, and the mass ratio of the donor material PM6 to the acceptor material L8-BO is 1:1.2.

[0104]

[0105] 4) Preparation of the second charge transport layer (anode buffer layer) 123

[0106] In high vacuum (1×10 -6 mbar) in MoO 3 The second charge transport layer is formed by evaporation onto the photoactive layer to have a thickness of about 10 nm.

[0107] 5) Preparation of the second electrode layer (Ag / ITO) 13

[0108] In high vacuum (1×10 -6 Ag was evaporated onto the second charge transport layer in a vacuum atmosphere (1×10 -6 The ITO thin film layer was prepared under the conditions of 1.1 kW and 0.4 Å / s, wherein the deposition power was set to 1.1 kW and the sputtering rate was set to 0.4 Å / s. Before depositing the ITO thin film on the ultra-thin metal Ag layer, the target material was pre-sputtered for 10 minutes to remove possible impurities. Then, the ITO thin film was deposited at a temperature of 40°C, and the thickness of the sputtered ITO thin film was about 150 nm to obtain a transparent electrode layer 132.

[0109] 6) Packaging

[0110] The devices were encapsulated with UV-curable resin in a nitrogen glove box.

[0111] Device Example 2:

[0112] The preparation method of device embodiment 2 is the same as that of device embodiment 1, except that the preparation thickness of the second electrode layer (Ag / ITO) 13 is different, as follows:

[0113] In high vacuum (1×10 -6 Ag was evaporated onto the second charge transport layer in a pure argon atmosphere at a high vacuum (1×10 -6 The ITO thin film layer was prepared under the conditions of 1.1KW (millibar), where the deposition power was set to 1.1KW and the sputtering rate was set to 0.4 Å / s. Before depositing the ITO thin film on the ultra-thin metal Ag layer, the target material was pre-sputtered for 10 minutes to remove possible impurities. Then, the ITO thin film was deposited at a temperature of 40°C, and the thickness of the sputtered ITO film was about 150 nm.

[0114] Device Example 3:

[0115] The preparation process of device embodiment 3 is the same as that of device embodiment 1, except that the preparation thickness of the second electrode layer (Ag / ITO) 13 is different, as follows:

[0116] In high vacuum (1×10 -6 Ag was evaporated onto the second charge transport layer in a pure argon atmosphere at a high vacuum (1×10- 6 The ITO thin film layer was prepared under the conditions of 1.1KW (millibar), where the deposition power was set to 1.1KW and the sputtering rate was set to 0.4 Å / s. Before depositing the ITO thin film on the ultra-thin metal Ag layer, the target material was pre-sputtered for 10 minutes to remove possible impurities. Then, the ITO thin film was deposited at a temperature of 40°C, and the thickness of the sputtered ITO film was about 150 nm.

[0117] Device Example 4:

[0118] The preparation process of device embodiment 4 is the same as that of device embodiment 1, except that the preparation thickness of the second electrode layer (Ag / ITO) 13 is different, as follows:

[0119] In high vacuum (1×10 -6 Ag was evaporated onto the second charge transport layer in a pure argon atmosphere at a high vacuum (1×10 -6 The ITO thin film layer was prepared under the conditions of 1.1KW (millibar), where the deposition power was set to 1.1KW and the sputtering rate was set to 0.4 Å / s. Before depositing the ITO thin film on the ultra-thin metal Ag layer, the target material was pre-sputtered for 10 minutes to remove possible impurities. Then, the ITO thin film was deposited at a temperature of 40°C, and the thickness of the sputtered ITO film was about 150 nm.

[0120] Device Comparison Example 1:

[0121] The preparation process of device comparative example 1 is the same as that of device example 1, except that the preparation method of the second electrode layer 13 is different, as follows:

[0122] In pure argon atmosphere, high vacuum (1×10 -6 The ITO thin film layer was prepared under the conditions of 1.1KW (millibar), where the deposition power was set to 1.1KW and the sputtering rate was set to 0.4 Å / s. Before depositing the ITO thin film on the second charge transport layer, the target material was pre-sputtered for 10 minutes to remove possible impurities. Then, the ITO thin film was deposited at a temperature of 40°C, and the thickness of the sputtered ITO film was about 150 nm.

[0123] The device structures of specific device embodiments 1-5 and device comparison embodiment 1 are shown in Table 1:

[0124] Table 1

[0125]

[0126] The prepared semi-transparent organic photovoltaic cell was subjected to a performance test. Under the irradiation of the AM1.5 standard light of the solar simulator, the current-voltage curve of the cell was tested and the photoelectric conversion efficiency was calculated. The specific values ​​are shown in Table 2:

[0127] Table 2

[0128]

[0129] It can be seen from the data in Table 2 that when the semi-transparent organic photovoltaic cell described in the present application introduces an ultra-thin metal layer as an electrode buffer layer, compared with the device structure without an ultra-thin metal layer, both the short-circuit current density and the fill factor are uniformly and significantly improved, so that the photoelectric conversion efficiency of the device is significantly improved compared with the device comparison example 1.

[0130] Device Example 5:

[0131] The preparation process of device embodiment 5 is the same as that of device embodiment 1, except that the thickness of the second electrode layer (Ag / ITO) 13 is different, as follows:

[0132] In high vacuum (1×10 -6 Ag was evaporated onto the second charge transport layer in a pure argon atmosphere at a high vacuum (1×10 -6 The ITO thin film layer was prepared under the conditions of 1.1KW and 0.4 Å / s, where the deposition power was set to 1.1KW and the sputtering rate was set to 0.4 Å / s. Before depositing the ITO thin film on the ultra-thin metal Ag layer, the target was pre-sputtered for 10 minutes to remove possible impurities. Then, the ITO thin film was deposited at a temperature of 40°C, and the thickness of the sputtered ITO film was about 100 nm.

[0133] Device Example 6:

[0134] The preparation process of device embodiment 6 is the same as that of device embodiment 1, except that the preparation thickness of the second electrode layer (Ag / ITO) 13 is different, as follows:

[0135] In high vacuum (1×10 -6 Ag was evaporated onto the second charge transport layer in a pure argon atmosphere at a high vacuum (1×10 -6The ITO thin film layer was prepared under the conditions of 1.1KW (millibar), where the deposition power was set to 1.1KW and the sputtering rate was set to 0.4 Å / s. Before depositing the ITO thin film on the ultra-thin metal Ag layer, the target material was pre-sputtered for 10 minutes to remove possible impurities. Then, the ITO thin film was deposited at a temperature of 40°C, and the thickness of the sputtered ITO film was about 200 nm.

[0136] The device structures of device embodiments 3, 5 and 6 are shown in Table 3:

[0137] Table 3

[0138]

[0139] The prepared semi-transparent organic photovoltaic cell was subjected to a performance test. Under the irradiation of the AM1.5 standard light of the solar simulator, the current-voltage curve of the cell was tested and the photoelectric conversion efficiency was calculated. The specific values ​​are shown in Table 4:

[0140] Table 4

[0141]

[0142] Device Example 7:

[0143] like Figure 2 As shown, the semi-transparent organic photovoltaic cell device structure: substrate / ITO / PEI-Zn / PM6:L8-BO / MoO 3 / Ag / ITO, device area: 5*5cm 2 , the number of organic photovoltaic cell units: 7. The specific preparation steps are as follows:

[0144] a. Provide a conductive glass containing a first electrode layer 11 (the substrate 10 is selected from glass, and the first electrode layer is selected from ITO), etch an insulating channel P1 on the first electrode layer 11 by 20 nanosecond green light, and the insulating channel P1 will extend through the first electrode layer 11 to the glass substrate 10, then clean the ITO conductive glass with the insulating channel P1 with a detergent, rinse it, and then ultrasonically clean it with deionized water, acetone, and isopropanol for 15 minutes, then blow it dry with nitrogen and treat it in a plasma cleaner for 5 minutes to further clean the surface and improve wettability.

[0145] b. Prepare a first charge transport layer 121 by spin coating, wherein the first charge layer material is PEI-Zn, the spin coating speed is 1500 rpm, the spin time is 30 s, and the first charge transport layer 121 is dried at 150° C. for 10 min to obtain the first charge transport layer 121; prepare a photoactive layer 122 by spin coating on the first charge transport layer 121, wherein the photoactive layer material is selected from PM6:L8-BO, the mass ratio of PM6 to L8-BO is 1:1.2, and the total concentration of PM6 and L8-BO in toluene is 17.6 mg / mL, to obtain a photoactive layer 122 with a thickness of about 100 nm, and then prepare a second charge transport layer 123 by vacuum evaporation on the photoactive layer 122, wherein the second charge transport layer material is selected from MoO 3 , a second charge transport layer 123 with a thickness of 10 nm is obtained, the functional layer 12 is formed as a whole, and a connecting channel P2 is etched out by green nanosecond laser, and the connecting channel P2 penetrates the functional layer 12 to the first electrode layer 11.

[0146] c. Prepare an electrode buffer layer 131 on the functional layer 12 by vacuum evaporation. The electrode buffer layer material is selected from Ag and has a thickness of 12 nm.

[0147] d. In pure argon atmosphere, high vacuum (1×10 -6 The ITO thin film layer was prepared under the conditions of 1.1 kW and 0.4 Å / s, wherein the deposition power was set to 1.1 kW and the sputtering rate was set to 0.4 Å / s. Before depositing the ITO thin film, the target material was pre-sputtered for 10 minutes to remove possible impurities. Then, the ITO thin film was deposited at a temperature of 40°C, and the sputtered ITO thin film had a thickness of about 150 nm, thereby obtaining a transparent battery layer 132. Then, a partition channel P3 was obtained on the ITO thin film layer by green nanosecond laser etching, and the partition channel P3 at least penetrated the second electrode layer 13.

[0148] e. When packaging the battery module, place the upper cover plate 15 on the platform. The upper cover plate 15 is transparent glass. Apply UV curing glue on the upper cover plate 15 by dispensing. Then, place the battery to be packaged facing downward and align it with the upper cover plate 15. Apply a certain pressure on the upper cover plate so that the substrate 10 and the upper cover plate 15 are tightly combined by the UV packaging glue. Then, irradiate the upper cover plate with a 365nm ultraviolet light source with an energy of 6J / cm2 for 70s to cure the UV packaging glue and form a sealing glue layer 14, thereby obtaining the following. Figure 2 The battery structure shown in the figure is shown in Figure 3 .

[0149] Device Comparative Example 2:

[0150] The preparation process of device comparative example 2 is the same as that of device example 7, except that step c is not included in device comparative example 2. That is, the device structure is: substrate / ITO / PEI-Zn / PM6:L8-BO / MoO 3 / ITO

[0151] Device Comparison Example 3:

[0152] The preparation process of device comparative example 3 is the same as that of device example 7, except that the preparation method of step d in device comparative example 3 is different—no transparent battery layer 132 is provided, specifically, step d, then a partition channel P3 is obtained on the electrode buffer layer 131 by green nanosecond laser etching, and the partition channel P3 at least penetrates the electrode buffer layer 131. That is, the device structure is: substrate / ITO / PEI-Zn / PM6:L8-BO / MoO 3 / Ag

[0153] The device structures of specific device embodiment 7 and device comparison embodiments 2-3 are shown in Table 5:

[0154] Table 5

[0155]

[0156] The prepared semi-transparent organic photovoltaic cell was subjected to a performance test. Under the irradiation of the AM1.5 standard light of the solar simulator, the current-voltage curve of the cell was tested and the photoelectric conversion efficiency was calculated. The specific values ​​are shown in Table 6:

[0157] Table 6

[0158]

[0159] It can be seen from the data in Table 6 that the semi-transparent organic photovoltaic cell device according to the present invention exhibits better photoelectric conversion efficiency when preparing a large-area module compared to when a pure thin metal layer or pure ITO is used as the second electrode.

[0160] Device Examples 8-10:

[0161] The preparation methods of device embodiments 8-10 are the same as those of device embodiment 7, except that the thickness of the counter electrode buffer layer and the transparent electrode layer in step c and step d are set differently, as described in Table 7. Figures 3 to 6 The present invention realizes color tunability of the device by adjusting the thickness of the electrode buffer layer and the transparent electrode layer in the second electrode layer, as shown in Table 7 for details.

[0162] Table 7

[0163]

[0164] The above examples further illustrate the content of the present application, but should not be construed as limiting the present application. Without departing from the spirit and substance of the present application, modifications and replacements made to the methods, steps or conditions of the present application all fall within the scope of the present application. Unless otherwise specified, the technical means used in the examples are conventional means well known to those skilled in the art.

Claims

1. A semi-transparent organic photovoltaic cell device, comprising a substrate, a first electrode layer, a functional layer and a second electrode layer stacked in sequence from bottom to top, characterized in that: The second electrode layer includes an electrode buffer layer and a transparent electrode layer. The electrode buffer layer is located between the functional layer and the transparent electrode layer. The material of the electrode buffer layer is selected from metal or metal alloy, and the thickness of the electrode buffer layer is selected from 7-30 nm.

2. The semi-transparent organic photovoltaic cell device according to claim 1, characterized in that: The transparent electrode layer is selected from a conductive metal oxide layer, or a composite conductive layer comprising a conductive metal oxide layer and a metal layer.

3. The semi-transparent organic photovoltaic cell device according to claim 1, characterized in that: The thickness of the electrode buffer layer is selected from 7-20 nm; preferably, the thickness of the electrode buffer layer is selected from 7-15 nm.

4. The semi-transparent organic photovoltaic cell device according to claim 1, characterized in that: The electrode buffer layer material is selected from silver, aluminum, gold, copper, magnesium, cadmium, or alloys of the above metals.

5. The semi-transparent organic photovoltaic cell device according to claim 2, characterized in that: The transparent electrode layer material is selected from indium oxide, zinc oxide, tin oxide, indium tin oxide, fluorine-doped tin oxide, gallium-doped zinc oxide, aluminum-doped zinc oxide, indium zinc oxide, indium gallium zinc oxide, indium tin oxide / silver / indium tin oxide, or indium tin oxide / copper / indium tin oxide.

6. The semi-transparent organic photovoltaic cell device according to claim 2, characterized in that: The thickness of the transparent electrode layer is selected from 30-200 nm; preferably, the thickness of the transparent electrode layer is selected from 50-200 nm.

7. The semi-transparent organic photovoltaic cell device according to claim 1, characterized in that: The electrode buffer layer material is selected from silver, and the transparent electrode layer material is selected from indium tin oxide.

8. The semi-transparent organic photovoltaic cell device according to any one of claims 1 to 7, characterized in that: The substrate is selected from a light-transmitting substrate; the first electrode layer material is selected from a transparent or translucent conductive material; the functional layer comprises a first charge transport layer, a photoactive layer and a second charge transport layer; the first charge transport layer is located between the first electrode layer and the photoactive layer, and the second charge transport layer is located between the second electrode layer and the photoactive layer.

9. The semi-transparent organic photovoltaic cell device according to any one of claims 1 to 7, characterized in that: The semi-transparent organic photovoltaic cell device comprises one or more organic photovoltaic cell units. When the semi-transparent organic photovoltaic cell device comprises multiple organic photovoltaic cell units, the multiple organic photovoltaic cell units are connected in series or in parallel.

10. A method for preparing a semi-transparent organic photovoltaic cell device, characterized in that: The preparation method comprises the following steps: S1. providing a substrate; S2, preparing a first electrode layer on the substrate; S3, preparing a functional layer on the first electrode layer; S4, preparing a second electrode layer on the functional layer; S5, packaging; Wherein: the second electrode layer includes an electrode buffer layer and a transparent electrode layer; in step S4, the electrode buffer layer is first prepared on the functional layer by vacuum evaporation; and then the transparent electrode layer is prepared on the electrode buffer layer by sputtering; the electrode buffer layer material is selected from metal or metal alloy, and the electrode buffer layer thickness is selected from 7-30nm.

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