Anti-dazzle semitransparent organic photovoltaic glass window based on thermal nanoimprint lithography and preparation method of anti-dazzle semitransparent organic photovoltaic glass window

Abstract

The invention discloses an anti-dazzle semitransparent organic photovoltaic glass window based on thermal nanoimprint lithography and a preparation method of the anti-dazzle semitransparent organic photovoltaic glass window, and belongs to the technical field of photovoltaic building integration. A submicron grating structure is prepared on the surface of a ternary blending active layer through a thermal nanoimprint process, and a device structure with a metasurface light field regulation effect is formed after spin coating of an electron transport layer and evaporation of a metal top electrode. By introducing a grating structure and utilizing diffraction and scattering effects, energy of reflected light is redistributed to a non-mirror direction, zero-order mirror reflection is remarkably inhibited, glare is effectively inhibited, light pollution is reduced, and meanwhile, the polarization degree of the reflected light is reduced and the visual comfort is improved by differentially modulating S and P polarized light; for transmission light, the grating excites multi-order diffraction, resulting in angle dispersion of a light beam propagation path, increase of the optical path of light in the active layer, and enhancement of photon capture and absorption, thereby significantly improving the short-circuit current density and power conversion efficiency of the device while ensuring high light transmission.

Description

Technical Field

[0001] This invention relates to a semi-transparent organic photovoltaic device with a grating structure fabricated using a thermal nanoimprinting process, belonging to the field of building-integrated photovoltaics and optoelectronic devices. Background Technology

[0002] With the acceleration of global urbanization, glass curtain walls, as the "skin" of modern buildings, have been widely used in skyscrapers, commercial centers, and public facilities due to their lightweight, good lighting, and aesthetically pleasing modern appearance. However, the widespread use of large-area glass curtain walls has also brought serious problems of "light pollution" and energy consumption. Especially under certain lighting conditions, the glass surface will produce strong directional specular reflections, forming glare. This glare is usually characterized by high light intensity, high contrast, strong directionality, and high polarization (the reflected light is mainly S-polarized light when close to Brewster's angle). This not only seriously affects the visual safety of pedestrians and drivers, inducing traffic accidents, but also projects high-intensity reflected light into surrounding residential buildings, disturbing the normal lives of residents. To address this issue, the construction industry and environmental protection departments have issued several standards (such as GB / T 18091-2015 "Photothermal Performance of Glass Curtain Walls"), strictly limiting the visible light reflectance of glass curtain walls and advocating the use of anti-glare measures. For example, glass curtain walls should use glass with a visible light reflectance of no more than 0.30; glass curtain walls on buildings within 20 meters of each other on urban expressways, main roads, overpasses, and elevated bridges, and within 10 meters of each other on general roads, should use glass with a visible light reflectance of no more than 0.16. Currently, the main methods for controlling glare in the construction field include using low-emissivity (Low-E) coatings, frosted finishes, or installing physical sunshade grilles. However, these passive methods often come at the cost of sacrificing the light transmittance and clarity of the glass, and they do not have energy production capabilities or the ability to actively regulate the light field.

[0003] Against this backdrop, Building Integrated Photovoltaics (BIPV) technology has emerged, particularly semi-transparent organic photovoltaic (STOPV) devices. Due to their advantages such as adjustable bandgap, rich colors, flexibility, and large-area printing capabilities, they are considered an ideal solution to the energy-aesthetic conflict and an alternative to traditional glass curtain walls. While current STOPV devices have made significant progress in balancing photoelectric conversion efficiency (PCE) and average visible light transmittance (AVT), their optical structure design still has shortcomings. Most existing STOPVs employ planar multilayer thin-film structures, typically containing transparent electrodes with high refractive indices (such as ITO, n≈1.9) and an organic semiconductor active layer (n≈1.8-2.2). According to Fresnel optics principles, this high-refractive-index planar stacked structure often exhibits a stronger reflection effect than ordinary glass under oblique incident light, and the reflected light has a higher degree of polarization. This makes its anti-glare performance even inferior to ordinary glass, greatly limiting its application in urban building facades.

[0004] To address the aforementioned optical challenges and enhance photovoltaic performance, micro- and nano-optical structures have been introduced into photovoltaic devices. Among these, nanoimprint lithography (NIL), a high-throughput, low-cost, and high-resolution micro- and nano-fabrication technology, has experienced rapid development in the field of optoelectronic device manufacturing in recent years. Its basic principle involves transferring nanopatterns from a template onto a substrate coated with a polymer fluid using mechanical pressure, followed by curing and setting through heating or ultraviolet light. Compared to expensive and inefficient electron beam lithography or focused ion beam etching, nanoimprint technology can rapidly fabricate high-fidelity nanostructures on large-area flexible substrates, making it ideal for roll-to-roll production of organic photovoltaic devices. Nanoimprint technology boasts high applicability; by changing different templates, various metasurface morphologies, such as one-dimensional gratings, two-dimensional photonic crystals, biomimetic moth-eye structures, or random scattering structures, can be easily constructed on or inside the device surface, thereby achieving precise control over photon propagation paths.

[0005] More importantly, nanoimprinting technology has broad applicability to organic photovoltaic active layer material systems. Whether it's classic polymer donor / fullerene acceptor systems (such as P3HT:PCBM), currently high-efficiency polymer donor / non-fullerene acceptor systems (such as PM6:Y6 and its derivatives), all-small molecule systems, polymer / polymer systems, or even material systems based on imide or fused-ring narrow bandgap acceptors, all utilize their thermal rheological properties (thermoplasticity) to directly form micro / nano structures on the active layer surface through thermal nanoimprinting. This universality makes introducing light management structures through nanoimprinting a common strategy for improving the performance of various organic photovoltaic devices.

[0006] However, although nanoimprint technology has been studied to improve the light-harvesting ability of devices, current research mainly focuses on simply improving photoelectric conversion efficiency, lacking a systematic design for anti-glare functions in practical BIPV applications. Existing stop-wave devices often use thinner active layers to achieve high light transmittance. While this increases transmission, it sacrifices photon harvesting efficiency, resulting in a lower short-circuit current density (Jsc). Simply increasing the thickness of the active layer leads to decreased transmittance and increased charge recombination. Therefore, there is still a lack of an integrated technology solution that can simultaneously resolve the contradictions between "high-efficiency power generation (high Jsc)," "high transmittance (high AVT)," and "anti-glare / low light pollution (low reflection, low polarization)."

[0007] Based on the aforementioned technical background, this invention proposes an anti-glare semi-transparent organic photovoltaic glass window and its fabrication method based on thermal nanoimprinting technology. This invention fully utilizes the excellent molding capability of thermal nanoimprinting technology for ternary blend active layers (such as polymer / fused ring narrow bandgap acceptor systems) to introduce a submicron grating structure on the surface of the active layer. By leveraging the grating's ability to modulate the light field (diffraction, scattering, and mode coupling), dual optimization of reflected and transmitted light is achieved: at the reflection end, glare is eliminated through spatial reconstruction and polarization reshaping; at the transmission end, light absorption is enhanced through the optical trapping effect. Thus, while effectively eliminating glare and reducing light pollution, the photoelectric conversion efficiency of the device is significantly improved, and good visual comfort is maintained. Summary of the Invention

[0008] The present invention provides an anti-glare semi-transparent organic photovoltaic glass window based on thermal nanoimprinting and its preparation method, which is achieved through the following steps: Step A: Select wide-bandgap polymer donor material PM6, small molecule non-fullerene acceptor material BTP-eC9 and L8-BO, accurately weigh and mix them according to a preset mass ratio, and dissolve them in an organic solvent, and stir evenly to obtain a ternary blend active layer solution.

[0009] Step B: Prepare a flexible mold with a submicron grating structure; preferably, polydimethylsiloxane (PDMS) is used as the soft mold material, which is obtained by casting spin coating onto a silicon wafer master mold with an etched grating structure, heating and curing, and cooling and peeling.

[0010] Step C: Clean and surface-treat the prepared ITO glass substrate. Then, spin-coat the hole transport layer PEDOT:PSS onto the ITO layer and perform heat annealing. After annealing, immediately transfer it into a vacuum glove box.

[0011] Step D: Spin-coat the ternary blend active layer solution prepared in step A onto the PEDOT:PSS layer obtained in step C, and anneal it in a nitrogen atmosphere to obtain a blend active layer film, which is then cooled to room temperature;

[0012] Step E: According to the substrate size and the preset grating arrangement direction, the flexible mold prepared in step B is cut and positioned under an optical microscope; the side of the flexible mold with the grating structure is completely covered and attached to the surface of the blended active layer film described in step D; the sample is heated to a temperature higher than the glass transition temperature (Tg) of the polymer donor material, and a preset pressure is applied to the flexible mold and kept at a constant temperature and pressure for a period of time; after the system cools down, the pressure is released and the mold is removed, thereby forming a submicron grating structure on the surface of the active layer through a hot stamping process;

[0013] Step F: Spin-coat an electron transport layer PDINN onto the active layer with a submicron grating structure obtained in step E. The electron transport layer PDINN conformally covers and fills the grating structure to form a PDINN layer. Subsequently, the organic functional layer of the substrate reserved anode contact area is removed by physical scraping or solvent wiping to expose the ITO electrode.

[0014] Step G: Transfer the sample processed in step F to the vacuum evaporation chamber, perform vacuum thermal evaporation on the electron transport layer PDINN through a mask, deposit an ultrathin silver (Ag) metal layer as a semi-transparent top electrode, and finally obtain a semi-transparent organic photovoltaic glass window with anti-glare function.

[0015] In step A of the above-mentioned invention, the mass ratio of the wide-bandgap polymer donor material PM6, the small molecule non-fullerene acceptor material BTP-eC9, and L8-BO in the ternary blend active layer solution is preferably 1:0.8:0.2; it is dissolved in chlorobenzene solvent in a nitrogen environment, and the total concentration of the solution (total concentration of PM6, BTP-eC9, and L8-BO) is 17-20 mg / mL, preferably 20 mg / mL, and 0.5% by volume of 1,8-diiodooctane (DIO) is added as a solvent additive.

[0016] In step B of the above-mentioned invention, the flexible mold is a polydimethylsiloxane (PDMS) soft mold, the period of the grating structure is preferably 1.8 μm, the depth is preferably 1 μm, and the duty cycle is 1:1. The preparation method is as follows: PDMS main agent and curing agent are mixed at a mass ratio of 1:1 and degassed, then poured onto a silicon wafer master mold with an etched grating structure. The spin coating speed is 600-1000 rpm, and the spin coating time is 10 s. Subsequently, it is placed in an oven at 130-150℃ for curing for 0.5-1 hour, and then cooled and peeled off to obtain the PDMS soft mold.

[0017] In step C of the above invention, after cleaning the ITO glass substrate, it is ultrasonicated twice each with deionized water, acetone, and anhydrous ethanol, for 15-20 min each. After drying with nitrogen, it is treated with ultraviolet ozone for 15 min. The hole transport layer is prepared using a PEDOT:PSS aqueous solution diluted with deionized water at a volume ratio of 1:1; preferably, the spin coating speed is 2700 rpm and the spin coating time is 40 s; after spin coating, it is baked and annealed at 140-170℃ for 15 min. After annealing, it is immediately transferred to a vacuum glove box for cooling in preparation of the subsequent active layer.

[0018] In step D of the above invention, preferably, the spin coating speed of PM6:BTP-eC9:L8-BO chlorobenzene solution is 3000 rpm and the spin coating time is 60 s; and it is baked and annealed at 100°C in a nitrogen atmosphere for 10 minutes.

[0019] In step E of the above invention, the holding temperature of the thermal nanoimprint should be higher than the glass transition temperature of the polymer donor PM6 to ensure that the active layer material has sufficient fluidity to fill the mold cavity. If the imprinting temperature is too low, the filling will be incomplete, and if the imprinting temperature is too high, the active layer may undergo excessive phase separation, affecting the device performance. The specific parameters of the thermal nanoimprint process are as follows: initial pressure temperature 50-100℃ (preferably 90℃); holding temperature 100-160℃ (preferably 150℃); holding pressure 5-15 bar (preferably 10 bar); holding time 5-15 min (preferably 10 min); depressurization temperature 20-40℃ (preferably 25℃); demolding temperature needs to be cooled to 15-25℃ (preferably 20℃).

[0020] In step F of the above invention, PDINN is dissolved in methanol solvent in a nitrogen atmosphere, with a solution concentration of 2.5 mg / mL. Preferably, the spin coating speed is 3000 rpm and the time is 35 s. Subsequently, the organic functional layer of the substrate in the reserved anode contact area is removed by physically scraping with a tool such as a doctor blade or wiping with an organic solvent such as chlorobenzene, exposing the ITO electrode.

[0021] In step G of the above invention, the vacuum degree is better than 3×10 -4 Evaporation is performed under Pa conditions, with the thickness of the ultrathin silver metal top electrode preferably being 25 nm, and the evaporation rate controlled at 0.1-1.0 Å / s.

[0022] This anti-glare semi-transparent organic photovoltaic glass window, while ensuring high light transmittance, demonstrates, through testing, that the optimal device achieves a high power conversion efficiency (PCE) of 16.55%, an average visible light transmittance (AVT) of 17.9%, and a light utilization efficiency (LUE) of 3.00%, while exhibiting a low anti-glare index (AGI) of 1.43% and a high BIPV comprehensive performance index (BCPI) of 2.10%. By introducing a submicron grating structure, the diffraction and scattering effects redistribute the originally concentrated zero-order specular reflection energy to higher-order diffraction orders in non-specular directions, achieving "spatial reconstruction" of reflected light and significantly reducing the intensity of reflected light directly entering the human eye. In addition, the grating has a differential modulation effect on S and P polarized light. This polarization reshaping mechanism effectively reduces the degree of polarization (Dop) of reflected light, resulting in an anti-glare index (AGI) as low as 1.43% and a BIPV comprehensive performance index (BCPI) as high as 2.10. Furthermore, the grating structure couples the transmitted light into a quasi-guided mode, altering the light propagation path within the device and significantly increasing the optical path length. This enhances photon capture and absorption in the near-infrared band, thereby significantly improving short-circuit current density (Jsc) and power conversion efficiency without reducing, and may even increase, the average visible light transmittance (AVT). This anti-glare semi-transparent organic photovoltaic glass window has broad application prospects in building curtain walls, windows, and other lighting components. Attached Figure Description

[0023] Figure 1 This is the fabrication process of the grating anti-glare semi-transparent organic photovoltaic glass window based on thermal nanoimprinting in this invention;

[0024] Figure 2 This is a device structure diagram of the semi-transparent organic photovoltaic glass window with a submicron grating structure in this invention;

[0025] Figure 3 This is a device structure diagram of the planar semi-transparent organic photovoltaic glass window without grating in this invention;

[0026] Figure 4 This is a comparison of the current density-voltage (JV) characteristic curves of the grating semi-transparent organic photovoltaic glass window and the planar semi-transparent organic photovoltaic glass window prepared in this invention;

[0027] Figure 5 This is a schematic diagram of the anti-glare principle of the grating semi-transparent organic photovoltaic glass window based on diffraction and scattering mechanisms in this invention;

[0028] Figure 6 This is a graph showing the variable-angle reflectance of the device prepared in this invention for S-polarized light; wherein, Figure 6 (a) is a flat, semi-transparent organic photovoltaic glass window. Figure 6 (b) is a translucent organic photovoltaic glass window with a grating;

[0029] Figure 7 This is a graph showing the variable-angle reflectance of the device prepared in this invention for P-polarized light; wherein, Figure 7 (a) is a flat, semi-transparent organic photovoltaic glass window. Figure 7 (b) is a translucent organic photovoltaic glass window with a grating;

[0030] Figure 8 This is a graph showing the transmittance of the device prepared in this invention for S-polarized light at varying angles; wherein, Figure 8 (a) is a flat, semi-transparent organic photovoltaic glass window. Figure 8 (b) is a translucent organic photovoltaic glass window with a grating;

[0031] Figure 9 This is a graph showing the transmittance of the device prepared in this invention for P-polarized light at varying angles; wherein, Figure 9 (a) is a flat, semi-transparent organic photovoltaic glass window. Figure 9 (b) is a translucent organic photovoltaic glass window with a grating;

[0032] Figure 10 This is a diffraction pattern of transmitted light from a planar semi-transparent organic photovoltaic glass window under vertical irradiation with a 480 nm wavelength laser, as shown in an embodiment of the present invention.

[0033] Figure 11 This is a diffraction pattern of the transmitted light from the grating semi-transparent organic photovoltaic glass window under vertical irradiation with a 480 nm wavelength laser in an embodiment of the present invention. Detailed Implementation

[0034] The present invention will now be described in detail with reference to the accompanying drawings and embodiments, but the present invention is not limited to these manufacturing examples.

[0035] In this invention, to comprehensively evaluate the device's overall performance in photovoltaic power generation, light transmission transparency, and anti-glare capabilities, the following theoretical basis and evaluation indicators are introduced: The reflection behavior of light on a dielectric surface follows Fresnel's law. As the angle at which light strikes the surface of a planar glass or planar photovoltaic device increases, the reflectivity rises sharply. Especially near Brewster's angle, the transverse magnetic mode (P) component of the reflected light is suppressed, while the transverse electric mode (S) component is strongly reflected, resulting in extremely high polarization of the reflected light. This high-intensity, high-polarization directional reflected light is the main cause of visual glare.

[0036] This invention defines the anti-glare index (AGI) to quantify the anti-glare performance of a device, and the calculation formula is shown in equation (1):

[0037] (1)

[0038] In the formula, AVR is the average reflectivity of the device in the visible light band (380-780 nm), characterizing the basic brightness of the reflected light; Dop is the absolute value of the polarization degree of the reflected light, defined as... , where R S and R P These represent the reflectivity of the device for S-rays and P-rays, respectively. The lower the AGI value, the weaker the intensity of the reflected light and the lower the degree of polarization, meaning a better anti-glare effect.

[0039] This invention defines the BCPI index to comprehensively evaluate the balance between power generation, lighting, and visual comfort of a device. The calculation formula is shown in equation (2):

[0040] (2)

[0041] In the formula, LUE is the light utilization efficiency, which is the product of power conversion efficiency (PCE) and average visible light transmittance (AVT); AGI is the anti-glare index defined by the above formula (1); the higher the BCPI value, the higher the overall optoelectronic benefit provided by the device per unit glare cost.

[0042] Example 1

[0043] This embodiment describes the fabrication of a semi-transparent organic photovoltaic glass window based on thermal nanoimprinting and an anti-glare grating. The specific fabrication process is as follows: Figure 1As shown: First, a flexible grating mold was prepared. A commercial silicon grating with a period of 1.8 μm, a depth of 1 μm, and a duty cycle of 1:1 was selected as the master mold. Polydimethylsiloxane (PDMS) main agent and curing agent were mixed at a mass ratio of 1:1 and degassed. This mixture was then poured onto the silicon wafer master mold with the grating structure etched on it. The spin coating speed was 600 rpm, and the spin coating time was 10 s. The mixture was then cured in a 150℃ oven for 0.5 hours. After cooling, the PDMS flexible stamp with a complementary grating structure was obtained by peeling. Next, device fabrication was performed. The etched ITO glass substrate was ultrasonically cleaned sequentially with deionized water, acetone, and ethanol for 20 minutes each. After nitrogen drying, it was treated with ultraviolet ozone for 15 minutes. A 1:1 diluted PEDOT:PSS aqueous solution was spin-coated onto the ITO substrate at a spin coating speed of 2700 rpm for 40 seconds. The hole transport layer was formed by annealing at 160℃ for 15 minutes. Subsequently, in a glove box under nitrogen atmosphere, a ternary blend solution of polymer donor PM6, non-fullerene acceptor BTP-eC9, and L8-BO was prepared at a mass ratio of 1:0.8:0.2, with chlorobenzene as the solvent and a total concentration of 20 mg / mL, containing 0.5% by volume of 1,8-diiodooctane (DIO) additive. The ternary blend active layer solution was spin-coated onto the PEDOT:PSS layer at 3000 rpm for 60 seconds and annealed at 100℃ for 10 minutes. After the solvent evaporated, the flexible mold was cut and positioned under an optical microscope according to the substrate size and the preset grating arrangement direction, and its grating surface was covered on the surface of the active layer. The mold was heated to 150℃ using a thermal nanoimprinter and subjected to 5-10... The pressure was maintained at bar for 10 minutes, and after the temperature dropped to 25°C, the pressure was released and the stamp was removed, forming a submicron grating structure on the surface of the active layer. Finally, a PDINN methanol solution (2.5 mg / mL, 3000 rpm, 35 s) was spin-coated onto the grating active layer to form a conformal electron transport layer. The organic layer in the anode contact area was removed by physical scraping or solvent wiping, and the sample was transferred to a vacuum evaporation chamber with a vacuum level better than 3 × 10⁻⁶. -4 Under Pa conditions, a 25 nm thick layer of silver (Ag) is thermally deposited using a mask as a semi-transparent top electrode. The deposition rate is controlled between 0.1 and 1.0 Å / s. This allows for the production of an anti-glare grating semi-transparent organic photovoltaic glass window. The device structure is as follows: Figure 2 As shown.

[0044] Example 2 (Comparative Example)

[0045] This embodiment prepares a planar semi-transparent organic photovoltaic glass window. The specific preparation process is as follows: The etched ITO glass substrate is ultrasonically cleaned sequentially with deionized water, acetone, and isopropanol for 15 minutes each. After being dried with nitrogen, it is treated with ultraviolet ozone for 20 minutes. A 1:1 diluted PEDOT:PSS aqueous solution is spin-coated onto the ITO substrate at a spin speed of 2700 rpm for 40 s. The substrate is then annealed at 160℃ for 15 minutes to form a hole transport layer. Subsequently, in a glove box under a nitrogen atmosphere, a ternary blend solution of polymer donor PM6, non-fullerene acceptor BTP-eC9, and L8-BO is prepared at a mass ratio of 1:0.8:0.2, with chlorobenzene as the solvent and a total concentration of 20 mg / mL, containing 0.5% by volume of 1,8-diiodooctane (DIO) additive. This solution is spin-coated at 3000 rpm for 60 seconds. The sample was coated onto a PEDOT:PSS layer and annealed at 100°C for 10 minutes. After solvent evaporation, a PDINN methanol solution (2.5 mg / mL, 3000 rpm, 35 s) was spin-coated onto the active layer to form an electron transport layer. The organic layer in the anode contact area was removed by physical scraping or solvent wiping. The sample was then transferred to a vacuum evaporation chamber and deposited under a vacuum level better than 3 × 10⁻⁶. -4 Under Pa conditions, a 25 nm thick layer of silver (Ag) is thermally deposited using a mask as a semi-transparent top electrode. The deposition rate is controlled between 0.1 and 1.0 Å / s, resulting in a planar semi-transparent organic photovoltaic glass window. The device structure is as follows: Figure 3 As shown. Photovoltaic performance tests were conducted on a flat semi-transparent organic photovoltaic glass window and a grating semi-transparent organic photovoltaic glass window under standard AM 1.5G illumination (100 mW / cm²), and the results are as follows. Figure 4 As shown, by comparing the JV characteristic curves, it can be found that the short-circuit current density (Jsc) of the planar semi-transparent organic photovoltaic glass window is 26.19 mA / cm², and the power conversion efficiency (PCE) is 16.28%. However, after introducing the grating structure, the Jsc of the grating semi-transparent organic photovoltaic glass window is significantly increased to 26.93 mA / cm², and the PCE is also increased to 16.55%. This performance enhancement is mainly attributed to the grating structure coupling the incident light into a quasi-conducting mode in the active layer through the diffraction effect, which extends the optical path and enhances photon capture. At the same time, the increased interface area is also conducive to the effective collection of charge, thus proving that the grating structure achieves a net increase in efficiency without sacrificing electrical performance.

[0046] Example 3

[0047] This embodiment provides a comparison of the optical performance of a flat semi-transparent organic photovoltaic glass window and a grating semi-transparent organic photovoltaic glass window to verify the anti-glare function of the grating semi-transparent organic photovoltaic glass window. For example... Figure 5The schematic diagram illustrating the anti-glare principle shows that when light shines on the grating surface, the periodic structure induces diffraction and scattering effects, redistributing the originally concentrated zero-order specular reflection energy to higher-order diffraction orders in non-specular directions, thereby reducing glare. To quantify this effect, the variable-angle optical parameters of the device under different polarization states were tested: [Comparison] Figure 6 (a) and Figure 6 (b) Figure 7 (a) and Figure 7 (b) It can be seen that within the incident angle range of 20°-60°, the total reflectivity of the grating semi-transparent organic photovoltaic glass is significantly lower than that of the planar semi-transparent organic photovoltaic glass for both S-polarized and P-polarized light, especially effectively suppressing strong specular reflection at large angles; at the same time, compared with Figure 8 (a) and Figure 8 (b) Figure 9 (a) and Figure 9 (b) It can be seen that the translucent organic photovoltaic glass with a grating maintains high light transmittance without drastic oscillations in the transmission spectrum, proving that its light-gathering performance is not compromised. To visually demonstrate the diffraction and spectral dispersion effect of the grating, a 480 nm wavelength laser beam was used to vertically illuminate the device for verification: [e.g., ...] Figure 10 As shown, after the laser passes through the planar semi-transparent organic photovoltaic glass, it only presents a single concentrated transmitted light spot, indicating that the light propagates in a straight line without diffraction; while as Figure 11 As shown, after the laser passes through the translucent organic photovoltaic glass with a grating, multiple clear and discrete diffraction spots appear on the screen. This spatial discretization of energy is related to... Figure 5 This confirms the principle behind the invention and strongly demonstrates that the grating semi-transparent organic photovoltaic glass of this invention converts concentrated light beams into soft diffracted light, thus verifying the anti-glare function of the grating semi-transparent organic photovoltaic glass window.

Claims

1. A method for preparing an anti-glare semi-transparent organic photovoltaic glass window based on thermal nanoimprinting, characterized in that, Includes the following steps: Step A: Select wide-bandgap polymer donor material PM6, small molecule non-fullerene acceptor materials BTP-eC9 and L8-BO, accurately weigh and mix them according to the preset mass ratio, dissolve them in an organic solvent, and stir evenly to obtain a ternary blend active layer solution. Step B: Prepare a flexible mold with a submicron grating structure; Step C: Clean and surface-treat the prepared ITO glass substrate. Then, spin-coat the hole transport layer PEDOT:PSS onto the ITO layer and perform heat annealing to obtain the PEDOT:PSS layer. Step D: Spin-coat the ternary blend active layer solution prepared in step A onto the PEDOT:PSS layer obtained in step C, and anneal it under nitrogen to obtain a blend active layer film, which is then cooled to room temperature; Step E: According to the substrate size and the preset grating arrangement direction, the flexible mold prepared in step B is cut and positioned under an optical microscope; the side of the flexible mold with the grating structure is completely covered and attached to the surface of the active layer described in step D; the sample is heated to a temperature higher than the glass transition temperature (Tg) of the polymer donor material, and a preset pressure is applied to the flexible mold and kept at a constant temperature and pressure for a certain period of time; after the system cools down, the pressure is released and the mold is removed, thereby forming a submicron grating structure on the surface of the active layer through a hot stamping process; Step F: Spin-coat the electron transport layer PDINN onto the active layer with grating structure obtained in step E. The electron transport layer conformally covers and fills the grating structure to form the PDINN layer. Subsequently, the organic functional layer of the substrate reserved anode contact area is removed by physical scraping or solvent wiping to expose the ITO electrode. Step G: The sample processed in step F is transferred to a vacuum evaporation chamber, and a thin silver (Ag) metal layer is deposited on the electron transport layer through a mask to serve as a semi-transparent top electrode, ultimately obtaining a semi-transparent organic photovoltaic glass window with anti-glare function.

2. The method for preparing an anti-glare semi-transparent organic photovoltaic glass window based on thermal nanoimprinting according to claim 1, characterized in that, In step A of the invention described above, the organic photovoltaic active layer solution is prepared by dissolving a ternary mixture consisting of polymer donor PM6, non-fullerene small molecule acceptor BTP-eC9, and L8-BO in an organic solvent; the mass ratio of PM6:BTP-eC9:L8-BO is 1:0.8:0.2; the solvent is chlorobenzene, and 0.5% by volume of 1,8-diiodooctane (DIO) is added as an additive; the total concentration of the solution is 17-20 mg / mL, preferably 20 mg / mL.

3. The method for preparing an anti-glare semi-transparent organic photovoltaic glass window based on thermal nanoimprinting according to claim 1, characterized in that, In step B, the flexible mold is a polydimethylsiloxane (PDMS) soft mold, which is prepared by mixing the PDMS main agent and the curing agent at a mass ratio of 1:1, degassing, and then pouring it onto a silicon wafer master mold with an etched grating structure. The spin coating speed is 600-1000 rpm and the spin coating time is 10 s. After curing at 130-150℃ for 0.5-1 hour, it is peeled off.

4. The method for preparing an anti-glare semi-transparent organic photovoltaic glass window based on thermal nanoimprinting according to claim 1, characterized in that, In step C, after cleaning the ITO glass substrate, it is ultrasonicated twice each with deionized water, acetone, and anhydrous ethanol, for 15-20 min each. After drying with nitrogen, it is treated with ultraviolet ozone for 15 min. The resulting PEDOT:PSS layer is annealed at 140-170℃ for 15 min. After annealing of the hole transport layer PEDOT:PSS layer, it is immediately transferred into a vacuum glove box, cooled, and then the blended active layer is prepared. In step D, preferably, the PM6:BTP-eC9:L8-BO chlorobenzene solution is spin-coated at 3000 rpm for 60 s; and then baked and annealed at 100℃ in a nitrogen atmosphere for 10 min.

5. A method for preparing an anti-glare semi-transparent organic photovoltaic glass window based on thermal nanoimprinting according to claim 1, characterized in that, In step E, the specific parameters of the thermal nanoimprinting process are as follows: initial pressure temperature 50-100℃ (preferably 90℃); holding temperature 100-160℃ (preferably 150℃); holding pressure 5-15 bar (preferably 10 bar); holding time 5-15 min (preferably 10 min); pressure release temperature 20-40℃ (preferably 25℃); and demolding temperature to be cooled to 15-25℃ (preferably 20℃).

6. A method for preparing an anti-glare semi-transparent organic photovoltaic glass window based on thermal nanoimprinting according to claim 1, characterized in that, In step F, the electron transport layer PDINN uses methanol as a solvent, with a solution concentration of 2.5 mg / mL, a spin-coating speed of 3000 rpm, and a spin-coating time of 35 s. Subsequently, the organic functional layer in the reserved anode contact area of ​​the substrate is removed by physical scraping or solvent wiping to expose the ITO electrode. In step G, the vacuum degree is better than 3 × 10⁻⁻⁻⁶. 4 Evaporation was performed under Pa conditions, with the thickness of the ultrathin silver metal top electrode being 25 nm, and the evaporation rate being controlled between 0.1 and 1.0 Å / s.

7. An anti-glare semi-transparent organic photovoltaic glass window based on thermal nanoimprinting, prepared according to any one of claims 1-6.

8. A translucent, anti-glare organic photovoltaic glass window based on thermal nanoimprinting according to claim 7, characterized in that, The photovoltaic glass window comprises, from bottom to top: a glass substrate, an ITO transparent conductive layer, a hole transport layer, an active layer with a submicron grating structure, an electron transport layer, and an ultrathin metal top electrode; the grating structure has diffraction and depolarization functions, which can suppress zero-order specular reflection and enhance photon capture in the near-infrared band.

9. The application of an anti-glare semi-transparent organic photovoltaic glass window based on thermal nanoimprinting as described in claim 8, characterized in that, Used in the field of building-integrated photovoltaics (BIPV), as building curtain walls, windows or skylights with functions of power generation, lighting, anti-glare and heat insulation.

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