A narrow-band optical detector with wide-angle detection and imaging capability and a method for preparing the same

Abstract

A narrowband light detector with wide-angle detection and imaging capabilities and a preparation method thereof, belonging to the field of light detection technology. The detector is composed of a hemispherical substrate, an anode, a hole transport layer, a perovskite film, an electron transport layer, a buffer layer and a cathode, or a hemispherical substrate, a cathode, an electron transport layer, a perovskite film, a hole transport layer and an anode, and the perovskite film PEA2FA3Pb4X 13 (X=Br, I or Br and I) is an active material for absorbing photons. The present invention deposits a quasi-two-dimensional perovskite film on a hemispherical substrate by introducing a solution spraying method, so that the photodetector has the characteristics of lens-free wide-angle response. By controlling the film thickness and changing the proportion of phenylethylamine cations, the recombination capacity at the surface short wave is improved, and the narrow-band response of the photodetector without a filter is achieved. The detector has low preparation cost and good narrow-band and wide-angle detection capabilities.

Description

Technical Field

[0001] The present invention belongs to the technical field of light detection, and in particular relates to a narrow-band light detector with wide-angle detection and imaging capability and a preparation method thereof. Background Art

[0002] Light detection is widely used in many fields such as optical communication, medical treatment, national defense, and detection of distant galaxies, and light detectors are one of the core technologies to achieve the above light detection applications. Therefore, the development of low-cost, color-recognizing, multi-angle-sensing spherical light detectors is an important research direction in the field of light detection technology.

[0003] Spherical detectors have a wider spatial detection range than flat detectors, and also reduce the detector's dependence on optical lenses. For traditional light detection materials, due to their rigid structure and high-temperature processing conditions, it is generally considered difficult to achieve the original preparation of devices on the surface of a sphere. It is feasible to use a solution spraying method to spray the perovskite precursor solution on a curved substrate to crystallize into a film. At the same time, during the spraying method, the extremely fast evaporation rate makes it difficult for the perovskite precursor droplets to dissolve during the crystallization process on the perovskite surface.

[0004] Quasi-two-dimensional perovskite materials have organic cations with larger radius that hinder the flow of carriers and have a widely adjustable band gap, which has good application prospects in narrow-band light detection. This is conducive to the preparation of low-cost, wide-angle detection narrow-band light detectors without optical lenses. Summary of the invention

[0005] The object of the present invention is to provide a narrow-band light detector with wide-angle detection and imaging capability and a preparation method thereof. The light detector has the advantages of wide spatial detection range, identifiable light color, and low cost.

[0006] The narrow-band light detector with wide-angle detection and imaging capability described in the present invention is composed of a hemispherical substrate, an anode, a hole transport layer, a perovskite film, an electron transport layer, a buffer layer and a cathode from bottom to top, or a hemispherical substrate, a cathode, an electron transport layer, a perovskite film, a hole transport layer and an anode, phenylethylamine formamidine lead halogen PEA2FA3Pb4X 13 (X=Br,I) perovskite thin films are active materials for absorbing photons.

[0007] The method for preparing a narrow-band light detector (hemispherical substrate, anode, hole transport layer, perovskite film, electron transport layer, buffer layer, cathode) with wide-angle detection and imaging capability described in the present invention is as follows: Figure 1 As shown, the steps are as follows:

[0008] (1) Select a hemispherical substrate with a diameter of 0.8 to 2 cm (made of ordinary glass, available from commercial channels), ultrasonically clean it in ultrapure water, acetone, and isopropanol for 10 to 20 minutes respectively, and then dry it;

[0009] (2) depositing metal Cr onto the surface of the hemispherical substrate as an anode by vacuum evaporation with a thickness of 8 to 15 nm, and then subjecting the metal Cr surface to UV-ozone treatment for 15 to 30 minutes and then plasma treatment for 5 to 10 minutes;

[0010] (3) Deposition of hole transport layer on the anode surface

[0011] (a) diluting a poly(3,4-ethylenedioxythiophene)-poly(styrene sulfonic acid) (PEDOT:PSS) aqueous solution with ultrapure water to obtain a hole transport layer solution having a PEDOT:PSS concentration of 0.05 to 0.2% wt;

[0012] (b) adding 400-1000 μL of the hole transport layer solution in step (a) into a pneumatic spray gun with a nozzle diameter of 0.2-0.5 mm;

[0013] (c) placing the hemispherical substrate with the anode prepared on the surface on a hot stage at 60-80° C., connecting the pneumatic spray gun in step (b) to an air compressor, with an output pressure of 1-3 MPa and a spraying rate of 0.10-0.3 mL / min, spraying the hole transport layer solution onto the surface of the anode, and during the spraying process, maintaining the rotation and translation of the hemispherical substrate, with a rotation speed of 0.20-0.30 r / min and a translation speed of 5-20 cm / s, so as to maintain the flatness of the sprayed film; during the spraying process, after each droplet of the solution completely covers the hemispherical surface, blowing the entire hemispherical surface with 4-7 MPa high-speed nitrogen to form a relatively dry film; when the solution is exhausted, annealing the film at 160-180° C. for 20-40 minutes, thereby obtaining a hole transport layer with a thickness of 10-100 nm on the anode surface;

[0014] (4) Deposition of PEA2FA3Pb4X on the surface of the hole transport layer 13 (X=Br, I or Br and I, the sum of their subscripts is 13) Perovskite film

[0015] (a) Formamidine hydrohalide (FAX), lead halide (PbX2), phenylethylamine hydrohalide (PEAX) and methylamine hydrochloride (MACl) were prepared according to the formula PEA2FA3Pb4X 13The precursor solution is configured with a molecular formula ratio of (X=Br, I) to have a lead ion concentration of 0.4 to 0.6M, the solvent is a mixed solvent of acetonitrile (ACN) and N,N-dimethylformamide (DMF), or a mixed solvent of ethylene glycol methyl ether (2-Me) and N,N-dimethylformamide (DMF), the volume ratio of acetonitrile (ACN) or ethylene glycol methyl ether (2-Me) to N,N-dimethylformamide (DMF) is 1:1 to 3, and the solubility of the precursor can be increased by adjusting the dosage ratio of N,N-dimethylformamide (DMF), so that the perovskite powder is completely dissolved;

[0016] (b) adding 500 to 2000 μL of the precursor solution prepared in step (a) into a pneumatic spray gun with a nozzle diameter of 0.2 to 0.5 mm;

[0017] (c) placing a hemispherical substrate with a hole transport layer deposited on the surface on a heating platform at 80-120° C., connecting the pneumatic spray gun in step (b) to an air compressor with an output pressure of 1-3 MPa, spraying the precursor solution onto the surface of the hole transport layer at a spraying rate of 0.1-0.3 mL / min; during the spraying process, the hemispherical substrate is kept rotating and translating at a rotation speed of 0.20-0.30 r / min and a translation speed of 5-20 cm / s, so as to maintain the flatness of the sprayed film; during the spraying process, after each droplet of the solution completely covers the hemispherical surface, the entire hemispherical surface is purged with 4-7 MPa high-speed nitrogen to form a relatively dry film;

[0018] (d) annealing the hemispherical substrate obtained in step (c) at 80-120° C. for 8-15 minutes, then annealing at 120-140° C. for 20-40 minutes, and finally annealing at 160-170° C. for 60-90 minutes, maintaining dark conditions during the annealing process, thereby obtaining a perovskite film with a thickness of 2-40 μm;

[0019] (5) The purchased fullerene (C 60 ) is evaporated onto the surface of the perovskite film to obtain an electron transport layer with a thickness of 15 to 30 nm;

[0020] (6) depositing purchased 2,9-dimethyl-4,7-biphenyl-1,10-phenanthroline (BCP) onto the surface of the electron transport layer by vacuum evaporation to obtain a buffer layer with a thickness of 4 to 10 nm;

[0021] (7) Vacuum evaporation is used to evaporate metal Cr onto the surface of the buffer layer as a cathode with a thickness of 8 to 15 nm; thereby preparing the narrow-band light detector with wide-angle detection and imaging capability of the present invention, the structure of which is hemispherical substrate / Cr / PEDOT:PSS / PEA2FA3Pb4X 13 / C 60 / BCP / Cr.

[0022] The preparation method of the second device structure (hemispherical substrate, cathode, electron transport layer, perovskite film, hole transport layer, anode) of the present invention comprises the following steps:

[0023] (1) Select a hemispherical substrate with a diameter of 0.8 to 2 cm (made of ordinary glass, available from commercial channels), ultrasonically clean it in ultrapure water, acetone, and isopropanol for 10 to 20 minutes respectively, and then dry it;

[0024] (2) depositing metal Cr onto the surface of the hemispherical substrate as a cathode by vacuum evaporation with a thickness of 8 to 15 nm, and then subjecting the metal Cr surface to UV-ozone treatment for 15 to 30 minutes and then plasma treatment for 5 to 10 minutes;

[0025] (3) Deposition of electron transport layer on the cathode surface

[0026] (a) diluting the purchased SnO2 aqueous solution with ultrapure water to prepare an electron transport layer solution with a SnO2 concentration of 0.05 to 0.1%wt;

[0027] (b) adding 400 to 1000 μL of the electron transport layer solution obtained in step (a) into a pneumatic spray gun with a nozzle diameter of 0.2 to 0.5 mm;

[0028] (c) placing the hemispherical substrate with the cathode prepared on the surface on a heating platform at 60-80° C., and connecting the pneumatic spray gun in step (b) to an air compressor, with an output pressure of 1-3 MPa and a spraying rate of 0.10-0.20 mL / min, spraying the electron transport layer solution onto the cathode surface; during the spraying process, the rotation and translation of the hemispherical substrate are maintained at a rotation speed of 0.20-0.30 r / min and a translation speed of 5-20 cm / s, so as to maintain the flatness of the sprayed film; during the spraying process, after each droplet of the solution completely covers the hemispherical surface, the entire hemispherical surface is purged with 4-7 MPa high-speed nitrogen to form a relatively dry film; when the solution is exhausted, the film is annealed at 160-180° C. for 20-40 minutes, and then subjected to UV-ozone treatment for 15-30 minutes, so as to obtain an electron transport layer with a thickness of 10-100 nm on the cathode surface;

[0029] (4) Deposition of PEA2FA3Pb4X on the surface of the electron transport layer 13 (X=Br, I or Br and I, the sum of their subscripts is 13) Perovskite film

[0030] (a) Formamidine hydrohalide (FAX), lead halide (PbX2), phenylethylamine hydrohalide (PEAX) and methylamine hydrochloride (MACl) were prepared according to the formula PEA2FA3Pb4X13 The molecular formula of (X=Br, I) is configured into a precursor solution with a lead ion concentration of 0.4 to 0.6M, the solvent is a mixed solvent of acetonitrile (ACN) and N,N-dimethylformamide (DMF), or a mixed solvent of ethylene glycol methyl ether (2-Me) and DMF, and the volume ratio of acetonitrile (ACN) or ethylene glycol methyl ether (2-Me) to N,N-dimethylformamide (DMF) is 1:1 to 3. By adjusting the dosage ratio of N,N-dimethylformamide (DMF), the solubility of the precursor can be increased, so that the perovskite powder is completely dissolved;

[0031] (b) adding 500 to 2000 μL of the precursor solution prepared in step (a) into a pneumatic spray gun with a nozzle diameter of 0.2 to 0.5 mm;

[0032] (c) placing a hemispherical substrate with an electron transport layer deposited on the surface on a heating platform at 80 to 120° C., connecting the pneumatic spray gun in step (b) to an air compressor with an output pressure of 1 to 3 MPa, spraying the precursor solution onto the surface of the electron transport layer at a spraying rate of 0.1 to 0.3 mL / min; during the spraying process, the rotation and translation of the hemispherical substrate are maintained at a rotation speed of 0.20 to 0.30 r / min and a translation speed of 5 to 20 cm / s, so as to maintain the flatness of the sprayed film; during the spraying process, after each droplet of the solution completely covers the hemispherical surface, the entire hemispherical surface is purged with 4 to 7 MPa of high-speed nitrogen to form a dry film;

[0033] (d) annealing the hemispherical substrate obtained in step (c) at 80-120° C. for 8-15 minutes, then annealing at 120-140° C. for 20-40 minutes, and finally annealing at 160-170° C. for 60-90 minutes, maintaining dark conditions during the annealing process; thereby obtaining a perovskite film with a thickness of 2-40 μm;

[0034] (5) Depositing a hole transport layer on the surface of the perovskite film, the steps are as follows:

[0035] (a) preparing a hole transport layer solution with a PTAA concentration of 0.05 to 0.2 mg / mL by mixing purchased poly[bis(4-phenyl)(2,4,6-trimethylphenyl)amine] (PTAA) with toluene;

[0036] (b) adding 400-1000 μL of the hole transport layer solution obtained in step (a) into a pneumatic spray gun with a nozzle diameter of 0.2-0.5 mm;

[0037] (c) fixing the hemispherical substrate with the perovskite film on the surface on a heating platform at 60-80° C., and connecting the pneumatic spray gun in step (b) to an air compressor, with an output pressure of 1-3 MPa and a spraying rate of 0.10-0.20 mL / min, spraying the hole transport layer solution onto the perovskite film. During the spraying process, the hemispherical substrate is rotated and translated at a rotation speed of 0.20-0.30 r / min and a translation speed of 5-20 cm / s, so as to maintain the flatness of the sprayed film; during the spraying process, after each droplet of the solution completely covers the hemispherical surface, the entire hemispherical surface is purged with high-speed nitrogen at 4-7 MPa to form a relatively dry film; when the solution is exhausted, the film is annealed at 90-110° C. for 5-15 minutes to obtain a hole transport layer with a thickness of 10-100 nm;

[0038] (6) By vacuum evaporation, metal Cr is evaporated onto the surface of the hole transport layer as an anode with a thickness of 8 to 15 nm, thereby preparing the narrow-band light detector with wide-angle detection and imaging capability of the present invention, the structure of which is hemispherical substrate / Cr / SnO2 / PEA2FA3Pb4X 13 / PTAA / Cr.

[0039] The imaging method of a narrow-band light detector with wide-angle detection and imaging capability described in the present invention comprises the following steps:

[0040] (a) A monochromatic LED light source with a central wavelength adjustable between 400 and 900 nm is fixed on an XY two-dimensional displacement platform, and the light source power is 3 to 10 W;

[0041] (b) connecting the XY two-dimensional displacement platform in step (a) to a computer to control its movement, with a moving unit distance of 200 to 500 μm / step;

[0042] (c) Connecting the LED light source in step (a) to a function generator (model: RIGOL DG1022Z), which outputs a square wave signal with a frequency of 20 to 90 Hz;

[0043] (d) placing the object to be tested (swan-shaped hairpin) on a glass platform below the LED light source, and placing the hemispherical narrow-band light detector prepared by the present invention under the glass platform;

[0044] (e) Adjust the angle of the hemispherical narrowband light detector described in step (d) so that it presents a certain angle with the imaging system (the angle between the incident light direction and the normal line of the bottom surface of the hemispherical light detector (ξ), the hemispherical detector can be used to change the ξ angle to control the detector to image at various angles by rotating along the center of the sphere, ξ=0°~90°), and then connect the hemispherical narrowband light detector to the preamplifier, the phase-locked amplifier and the computer; in the experiment, the function generator outputs a square wave signal to the light source and is in the same frequency as the phase-locked amplifier, the device receives the light signal and converts it into a current signal and outputs it to the preamplifier, the preamplifier converts the current signal into a voltage signal and amplifies it and transmits it to the phase-locked amplifier, the phase-locked amplifier further amplifies the voltage information from the preamplifier and the function generator in the same frequency signal and transmits it to the computer. Every time the stepper motor moves one step, a data point is read to form a data matrix.

[0045] (f) The voltage data matrix is ​​read by a computer, and finally the imaging results are obtained through MATLAB software.

[0046] Compared with the prior art, the narrow-band light detector with wide-angle detection capability and the preparation method thereof provided by the present invention have the following advantages:

[0047] The photodetector of the present invention attaches the perovskite precursor to a spherical substrate by spraying, thereby manufacturing a low-cost ultra-wide-angle photodetector without a lens at a low cost.

[0048] The photodetector of the present invention controls the attachment of the perovskite precursor to the spherical substrate by a spraying method, reasonably controls the thickness of the perovskite, and composites the surface carriers, so as to achieve the single wavelength response capability without the presence of a filter, and its narrow-band response reaches a half-height width of ~20nm.

[0049] The present invention uses a quasi-two-dimensional perovskite film (PEA2FA3Pb4X 13 ) as active materials. On the one hand, the large-volume cations can effectively recombine the carriers generated by the short wavelength on the surface and improve the stability of the perovskite. On the other hand, the addition of three-dimensional perovskite improves the adjustable detection range of the narrow-band detector. BRIEF DESCRIPTION OF THE DRAWINGS

[0050] Figure 1 To prepare PEA2FA3Pb4X on a hemispherical substrate 13Schematic diagram of the process of perovskite film; it is divided into steps such as spraying, nitrogen-assisted film formation, deposition cycle, and thermal annealing. As shown in the figure, the precursor solution is sprayed onto the surface of the hemispherical substrate by a pneumatic spray gun, and the film is quickly formed and dried under the action of nitrogen pressure; after drying, the precursor solution is continued to be sprayed onto the surface of the hemispherical surface for cyclic deposition; the whole process is completed at a certain temperature (80-120°C), thereby obtaining PEA2FA3Pb4X on the surface of the hemispherical substrate. 13 Perovskite film.

[0051] Figure 2 (a) Prepared PEA2FA3Pb4I 13 The optical photograph of the perovskite film shows that the spray-formed perovskite film has good film forming properties and flatness; Figure (b) is PEA2FA3Pb4X 13 The X-ray powder diffraction (XRD) test results of the perovskite film show that the film exhibits excellent crystallinity.

[0052] Figure 3 It is a schematic diagram of the structure of the photodetector of the present invention; as shown in the figure, the present invention includes two device structures in total: one device structure is composed of a hemispherical substrate 7, an anode 6, a hole transport layer 2, a perovskite film 1, an electron transport layer 3, a buffer layer 4 and a cathode 5, and the other device structure is composed of a hemispherical substrate f, a cathode d, an electron transport layer c, a perovskite film a, a hole transport layer b and an anode e.

[0053] Figure 4 (a) is a schematic diagram of a voltage-current density test system; in the figure, a light source with variable intensity is used to illuminate the device prepared by the present invention, a current source meter is connected to the positive and negative electrodes of the device, and then the current source meter is connected to a computer to measure different voltages. When the voltage is applied between the positive and negative electrodes of the device, the current density of the device under different light intensities is measured and plotted as a curve.

[0054] Figure 4 (b) Hemispherical substrate / Cr / PEDOT:PSS / PEA2FA3Pb4I 13 / C 60 Voltage-current density curves of the / BCP / Cr photodetector under different light intensities; the results show that the device exhibits low dark current and photoinduced voltage phenomenon, indicating that the device has relatively low noise and can operate with self-power.

[0055] Figure 5 (a) is a schematic diagram of the optical switch signal test system; in the figure, the signal generator gives a square wave signal to trigger the light source, and the light source outputs a square wave signal to the device surface; the device converts the collected optical signal into an electrical signal and outputs it to the oscilloscope to generate a square wave image; 820nm and 532nm light sources are used respectively, with light intensities of 0.72mW / cm 2and 2.17mW / cm 2 .

[0056] Figure 5 (b) Hemispherical substrate / Cr / PEDOT:PSS / PEA2FA3Pb4I 13 / C 60 The square wave signal of the / BCP / Cr photodetector triggered by light of different wavelengths; in the figure, the device has a clear square wave signal under 820nm light, but no obvious signal under 532nm light. The results show that the device can specifically recognize 820nm wavelength light, but has almost no response to 532nm light, which shows that the narrowband response effect of the device is significant.

[0057] Figure 6 (a) is a schematic diagram of the device wide-angle detection capability test system; in the figure, the position of the light source is variable and is used to adjust the angle of the incident light. The device is connected to a current source meter and a computer to read the electrical signal generated by the light detector for light at different incident angles.

[0058] Figure 6 (b) Hemispherical substrate or planar substrate / Cr / PEDOT:PSS / PEA2FA3Pb4I 13 / C 60 Angular response range curve of / BCP / Cr photodetector; the horizontal axis is the detection angle, and the vertical axis is the normalized photocurrent size; the results show that the hemispherical and planar photodetectors have different response capabilities to incident light at different angles, and the hemispherical photodetector exhibits extremely high wide-angle detection capabilities.

[0059] Figure 7 (a) is a schematic diagram of the device's narrowband detection capability test system; it is measured by external quantum efficiency (EQE). In the figure, the xenon light source passes through a monochromator and a chopper to output monochromatic light with a certain frequency to illuminate the detector. The current signal generated by the detector is amplified by the preamplifier and converted into a voltage signal. The same frequency signal is amplified again by a phase-locked amplifier and input into a computer to calculate the quantum efficiency by calculating the ratio of the current density generated by the detector to the photon density irradiating the detector.

[0060] Figure 7 (b) is a graph of the narrowband detection capability of light detectors with different structures; the horizontal axis is the wavelength, and the vertical axis is the normalized external quantum efficiency (EQE). The device structure for the 550nm response is hemispherical substrate / Cr / SnO2 / PEA2FA3Pb4Br 13 / PTAA / Cr, the device structure of 600nm response is hemispherical substrate / Cr / SnO2 / PEA2FA3Pb4Br 11I2 / PTAA / Cr, the device structure of 660nm response is hemispherical substrate / Cr / SnO2 / PEA2FA3Pb4Br8I5 / PTAA / Cr, and the device structure of 820nm response is hemispherical substrate / Cr / PEDOT:PSS / PEA2FA3Pb4I 13 / C 60 / BCP / Cr. This figure shows that we can successfully adjust the position of the response center wavelength of the narrowband detector by changing the relative ratio of I and Br in the halogen X. At the same time, its EQE at different wavelengths shows that it only responds near the center wavelength. At other positions, the EQE is very low, indicating that the detector has almost no response to light of other wavelengths, reflecting the narrowband detection nature of the narrowband detector.

[0061] Figure 8 The schematic diagram of the prepared photodetector imaging system is shown below; the function generator is connected to a monochromatic light source, the function generator outputs a square wave signal to the monochromatic light source and has the same frequency as the phase-locked amplifier, the device receives the light signal and converts it into a current signal and outputs it to the preamplifier, the preamplifier converts the current signal into a voltage signal and amplifies it and transmits it to the phase-locked amplifier, the phase-locked amplifier further amplifies the voltage information from the preamplifier and the function generator with the same frequency signal and transmits it to the computer. Every time the stepper motor moves one step, a data point is read to form a data matrix.

[0062] Fig. 9 Schematic diagram showing the specific imaging system and its relationship with the angle. The light source in the figure is a movable light source, which is driven to move by the translation stage. During specific imaging, the relative position of the object and the detector remains unchanged. After the imaging system is built, the range of the starting angle (θ1) and the ending angle (θ2) of the object imaging can be changed by rotating the angle of the detector (ξ is the angle between the normal of the hemisphere base and the normal of the glass platform on which the object to be imaged is placed, which can vary between -90° and 90°) and adjusting the position of the object. (a) shows a schematic diagram of the angle range occupied by the object and the relative position of the device when the angle is 0 degrees (ξ=0°). (b) shows a schematic diagram of the angle range occupied by the object and the relative position of the device when the angle is -90 degrees (ξ=-90°).

[0063] Fig.10 Schematic diagram of the imaging of objects occupying different imaging angles (from -52 degrees to -90 degrees and from -8 degrees to +30 degrees); because the detector is an axisymmetric structure, positive and negative signs are used to represent the detection and imaging capabilities of the device in the symmetrical orientation.

[0064] Fig.11 The imaging results of the prepared hemispherical light detector and the planar light detector are shown; Fig.11 (a) Planar light detector imaging results, the object angle ranges from -8 degrees to +30 degrees; Fig.11 (b) Planar light detector imaging results, the object angle ranges from -90 degrees to -52 degrees; Fig.11 (c) Hemispherical light detector imaging results, the object angle ranges from -8 degrees to +30 degrees; Fig.11 (d) The imaging result of the hemispherical light detector, the angles of the object range from -90 degrees to -52 degrees. This shows that the imaging ability of the spherical light detector at various angles is better than that of the planar detector. Especially for grazing angle (-90 degrees) imaging, the planar detector has almost no signal, while the hemispherical detector can still maintain the imaging effect. This shows that the hemispherical detector prepared by the spraying method has good wide-angle detection ability.

[0065] Fig.12 Imaging results of hemispherical light detectors with different structures under different monochromatic lights; Fig.12 (a) is 550nm monochromatic light, and the imaging device structure is hemispherical substrate / Cr / SnO2 / PEA2FA3Pb4Br 13 / PTAA / Cr, Fig.12 (b) is 600nm monochromatic light, and the imaging device structure is hemispherical substrate / Cr / SnO2 / PEA2FA3Pb4I2Br 11 / PTAA / Cr, Fig.12 (c) is 660nm monochromatic light, and the imaging device structure is hemispherical substrate / Cr / SnO2 / PEA2FA3Pb4I5Br8 / PTAA / Cr, Fig.12 (d) is a superimposed image of the above different monochromatic light imaging results. This type of imaging can more realistically represent the object, and each monochromatic image can provide great help for later image processing. DETAILED DESCRIPTION

[0066] Example 1: Structural characterization of the prepared perovskite film

[0067] (a) Formamidinium hydrohalide (FAI), lead halide (PbI2), phenylethylamine hydrohalide (PEAI) and methylamine hydrochloride (MACl) are prepared into a 0.6 M (relative to lead ions) precursor solution according to the molar ratio of 3:4:2:1.2. The solvent is acetonitrile (ACN) and N,N-dimethylformamide (DMF) in a volume ratio of 1:1. The solution is controlled to completely dissolve the perovskite powder.

[0068] (b) adding 2000 μL of the precursor solution prepared in step (a) into a pneumatic spray gun of model HD180 with a nozzle diameter of 0.2;

[0069] (c) Place the surface-modified hemispherical substrate on a heating platform at 100°C, and connect the pneumatic spray gun in step (b) to an air compressor with an output pressure of 1.7MPa. The spraying time is determined by the total spraying volume. The spraying rate is 0.13mL / min, and the hemispherical substrate is sprayed to obtain a perovskite wet film on the outer surface of the hemisphere; during the spraying process, the hemispherical substrate is kept rotating and translating at a rotation speed of 0.25r / min and a translation speed of 10cm / s to maintain the flatness of the sprayed film; during the spraying process, after each droplet of the solution completely covers the hemispherical surface, the entire hemispherical surface is purged with 5MPa high-speed nitrogen to form a relatively dry film;

[0070] (d) annealing the hemispherical substrate sprayed with the perovskite wet film obtained in step (c) at 120° C. for 10 minutes, then at 160° C. for 30 minutes, and finally at 170° C. for 60 minutes, maintaining dark conditions during the annealing process, and finally obtaining a perovskite film with a thickness of 25 μm; the molecular formula of the perovskite is PEA2FA3Pb4I 13 .

[0071] Figure 2 For the preparation of PEA2FA3Pb4I 13 Optical photograph (a) and XRD pattern (b) of the perovskite film, and the film shows excellent crystallinity.

[0072] Embodiment 2:

[0073] 1. Ultrasonic clean the hemispherical substrate (made of ordinary glass, with a diameter of 0.8 cm) in ultrapure water, acetone, and isopropanol for 15 minutes each, and then dry it in an oven;

[0074] 2. Vacuum evaporation was used to deposit metal Cr onto the surface of the hemispherical substrate as an anode with a thickness of 12 nm. The surface of the metal Cr was then treated with UV-ozone for 20 minutes and then with plasma for 5 minutes.

[0075] 3. The hole transport layer is deposited on the hemispherical surface, and the steps are as follows:

[0076] (a) diluting a poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonic acid) (PEDOT:PSS) aqueous solution with ultrapure water to obtain a hole transport layer solution with a PEDOT:PSS concentration of 0.1% wt;

[0077] (b) adding 800 μL of the hole transport layer solution in step (a) into a pneumatic spray gun of model HD180 with a nozzle diameter of 0.2 mm;

[0078] (c) placing a hemispherical substrate with an anode on the surface thereof on a hot stage at 65° C., connecting the pneumatic spray gun in step (b) to an air compressor, with an output pressure of 1.7 MPa and a spraying rate of 0.13 mL / min, spraying the hole transport layer solution onto the surface of the anode. During the spraying process, the hemispherical substrate is rotated and translated at a rotation speed of 0.25 r / min and a translation speed of 10 cm / s, thereby maintaining the flatness of the sprayed film; during the spraying process, after each droplet of the solution completely covers the surface of the hemispherical surface, the entire hemispherical surface is purged with 5 MPa high-speed nitrogen to form a dry film; when the solution is exhausted, the film is annealed at 170° C. for 30 minutes, thereby obtaining a hole transport layer with a thickness of 10 nm on the surface of the anode;

[0079] 4. PEA2FA3Pb4I 13 The perovskite film is deposited on the surface of the hole transport layer, and the steps are as follows:

[0080] (a) Formamidine hydrohalide (FAI), lead halide (PbI2), phenylethylamine hydrohalide (PEAI) and methylamine hydrochloride (MACl) are prepared into a 0.6 M (relative to lead ions) precursor solution according to the molar ratio of 3:4:2:1.2, and the solvent is a mixture of acetonitrile (ACN) and N,N-dimethylformamide (DMF) in a volume ratio of 1:1;

[0081] (b) adding 1500 μL of the precursor solution prepared in step (a) into a pneumatic spray gun of model HD180 with a nozzle diameter of 0.2;

[0082] (c) placing a hemispherical substrate with a hole transport layer deposited on the surface on a heating platform at 100° C., and connecting the pneumatic spray gun in step (b) to an air compressor with an output pressure of 1.7 MPa, spraying the hemispherical substrate at a spraying rate of 0.13 mL / min, and obtaining a perovskite wet film on the outer surface of the hemisphere; during the spraying process, the hemispherical substrate is kept rotating and translating at a rotation speed of 0.25 r / min and a translation speed of 10 cm / s, so as to maintain the flatness of the sprayed film, each time the droplets of the solution completely cover the surface once, and the entire surface is purged with 5 MPa high-speed nitrogen to form a relatively dry film;

[0083] (d) annealing the hemispherical substrate sprayed with the perovskite wet film obtained in step (c) at 120° C. for 10 minutes, then at 140° C. for 30 minutes, and finally at 170° C. for 60 minutes, maintaining dark conditions during the annealing process, and finally obtaining a perovskite layer with a thickness of 12 μm

[0084] 5. The purchased fullerene (C 60 ) is evaporated onto the surface of the perovskite film to obtain an electron transport layer with a thickness of 20 nm;

[0085] 6. Vacuum evaporation was used to deposit the purchased 2,9-dimethyl-4,7-biphenyl-1,10-phenanthroline (BCP) onto the surface of the electron transport layer to obtain a buffer layer with a thickness of 6 nm;

[0086] 7. Vacuum evaporation is used to evaporate metal Cr onto the surface of the buffer layer as a cathode with a thickness of 8 nm; thereby preparing the narrow-band light detector with wide-angle detection and imaging capability of the present invention, the structure of which is hemispherical substrate / Cr / PEDOT:PSS / PEA2FA3Pb4I 13 / C 60 / BCP / Cr.

[0087] Embodiment 3:

[0088] 1. Ultrasonic clean the hemispherical substrate (made of ordinary glass, with a diameter of 0.8 cm) in ultrapure water, acetone, and isopropanol for 15 minutes each, and then dry it in an oven;

[0089] 2. Vacuum evaporation was used to deposit metal Cr onto the surface of the hemispherical substrate as a cathode with a thickness of 15 nm. The surface of the metal Cr was then treated with UV-ozone for 20 minutes and then with plasma for 5 minutes.

[0090] 3. Deposit an electron transport layer on the cathode surface

[0091] (a) diluting the purchased SnO2 aqueous solution with ultrapure water to prepare an electron transport layer solution with a SnO2 concentration of 0.1%wt;

[0092] (b) adding 600 μL of the electron transport layer solution obtained in step (a) into a pneumatic spray gun of model HD180 with a nozzle diameter of 0.2 mm;

[0093] (c) placing a hemispherical substrate with a cathode on the surface on a 70°C heating table, and connecting the pneumatic spray gun in step (b) to an air compressor, with an output pressure of 2MPa and a spraying rate of 0.12mL / min, to spray the electron transport layer solution onto the cathode surface; during the spraying process, the hemispherical substrate is kept rotating and translating at a rotation speed of 0.25r / min and a translation speed of 15cm / s, so as to maintain the flatness of the sprayed film; during the spraying process, after each droplet of the solution completely covers the hemispherical surface, the entire hemispherical surface is purged with 5MPa high-speed nitrogen to form a relatively dry film; when the solution is exhausted, the film is annealed at 170°C for 30 minutes, and then subjected to UV-ozone treatment for 20 minutes, so as to obtain an electron transport layer with a thickness of 10nm on the cathode surface;

[0094] 4. PEA2FA3Pb4Br 13The perovskite film is deposited on the surface of the electron transport layer, and the steps are as follows:

[0095] (a) Formamidine hydrohalide (FABr), lead halide (PbBr2), phenylethylamine hydrohalide (PEABr) and methylamine hydrochloride (MACl) are prepared into a 0.5 M (relative to lead ions) precursor solution according to the molar ratio of 3:4:2:1.2. The solvent is a mixture of acetonitrile (ACN) and N,N-dimethylformamide (DMF) in a volume ratio of 2:3;

[0096] (b) adding 1200 μL of the precursor solution prepared in step (a) into a pneumatic spray gun of model HD180 with a nozzle diameter of 0.2;

[0097] (c) placing a hemispherical substrate with an electron transport layer deposited on the surface on a heating platform at 100° C., connecting the pneumatic spray gun in step (b) to an air compressor with an output pressure of 2 MPa, spraying the precursor solution onto the surface of the electron transport layer at a spraying rate of 0.15 mL / min; during the spraying process, the hemispherical substrate is rotated and translated at a rotation speed of 0.25 r / min and a translation speed of 10 cm / s, so as to maintain the flatness of the sprayed film; during the spraying process, after each droplet of the solution completely covers the hemispherical surface, the entire hemispherical surface is purged with 5 MPa high-speed nitrogen to form a relatively dry film;

[0098] (d) annealing the hemispherical substrate sprayed with the perovskite wet film obtained in step (c) at 120° C. for 10 minutes, then at 140° C. for 30 minutes, and finally at 170° C. for 60 minutes, maintaining dark conditions during the annealing process, and the thickness of the perovskite film is 10 μm;

[0099] 5. Deposit a hole transport layer on the surface of the perovskite film, the steps are as follows:

[0100] (a) Purchased poly[bis(4-phenyl)(2,4,6-trimethylphenyl)amine] (PTAA) and toluene were prepared into a hole transport layer solution with a PTAA concentration of 0.1 mg / mL;

[0101] (b) adding 400 μL of the hole transport layer solution in step (a) into a pneumatic spray gun of model HD180 with a nozzle diameter of 0.2 mm;

[0102] (c) Fix the hemispherical substrate with the perovskite film on the surface on a heating platform at 80°C, and connect the pneumatic spray gun in step (b) to an air compressor with an output pressure of 1.5MPa. The spraying time is determined by the total spraying volume. The spraying rate is 0.13mL / min, and the hemispherical substrate is sprayed to obtain a wet perovskite film on the outer surface of the hemisphere; during the spraying process, the rotation and translation of the hemispherical substrate are maintained, the rotation speed is 0.25r / min, and the translation speed is 10cm / s. Each time the droplets of the solution completely cover the surface, the entire surface is purged with 5MPa high-speed nitrogen to form a relatively dry film; when the solution is exhausted, the film hemisphere is annealed at 100°C for 10 minutes, and the thickness of the hole transport layer finally obtained is 10nm;

[0103] 6. Vacuum evaporation is used to evaporate metal Cr onto the surface of the hole transport layer as an anode with a thickness of 8 nm, thereby preparing the narrow-band light detector with wide-angle detection and imaging capability of the present invention, the structure of which is hemispherical substrate / Cr / SnO2 / PEA2FA3Pb4Br 13 / PTAA / Cr.

[0104] Embodiment 4:

[0105] 1. Select a hemispherical substrate with a diameter of 0.8 cm (made of ordinary glass, available from commercial channels), ultrasonically clean it in ultrapure water, acetone and isopropanol for 15 minutes respectively, and then dry it;

[0106] 2. Vacuum evaporation was used to deposit metal Cr onto the surface of the hemispherical substrate as a cathode with a thickness of 13 nm. The surface of the metal Cr was then treated with UV-ozone for 20 minutes and then with plasma for 5 minutes.

[0107] 3. Deposit an electron transport layer on the cathode surface

[0108] (a) diluting the purchased SnO2 aqueous solution with ultrapure water to prepare an electron transport layer solution with a SnO2 concentration of 0.1%wt;

[0109] (b) adding 600 μL of the electron transport layer solution obtained in step (a) into a pneumatic spray gun of model HD180 with a nozzle diameter of 0.2 mm;

[0110] (c) placing the hemispherical substrate with the cathode prepared on the surface on a 65°C heating table, and connecting the pneumatic spray gun in step (b) to an air compressor, with an output pressure of 2MPa and a spraying rate of 0.12mL / min, to spray the electron transport layer solution onto the cathode surface; during the spraying process, the hemispherical substrate is kept rotating and translating at a rotation speed of 0.25r / min and a translation speed of 15cm / s, so as to maintain the flatness of the sprayed film; during the spraying process, after each droplet of the solution completely covers the hemispherical surface, the entire hemispherical surface is purged with 5MPa high-speed nitrogen to form a relatively dry film; when the solution is exhausted, the film is annealed at 170°C for 30 minutes, and then subjected to UV-ozone treatment for 20 minutes, so as to obtain an electron transport layer with a thickness of 10nm on the cathode surface;

[0111] 4. PEA2FA3Pb4I2Br 11 The perovskite film is deposited on the surface of the electron transport layer, and the steps are as follows:

[0112] (a) Formamidine hydrohalide (FABr), lead halide (PbBr2), phenylethylamine hydrohalide (PEAI) and methylamine hydrochloride (MACl) are prepared into a 0.5M (relative to lead ions) precursor solution according to the molar ratio of 3:4:2:1.2, and the solvent is a mixture of acetonitrile (ACN) and N,N-dimethylformamide (DMF) in a volume ratio of 2:3, and the solution is controlled to completely dissolve the perovskite powder;

[0113] (b) adding 1500 μL of the precursor solution prepared in step (a) into a pneumatic spray gun of model HD180 with a nozzle diameter of 0.2;

[0114] (c) placing a hemispherical substrate with an electron transport layer deposited on the surface on a heating platform at 100° C., connecting the pneumatic spray gun in step (b) to an air compressor with an output pressure of 2 MPa, spraying the precursor solution onto the surface of the electron transport layer at a spraying rate of 0.15 mL / min; during the spraying process, the hemispherical substrate is rotated and translated at a rotation speed of 0.25 r / min and a translation speed of 10 cm / s, so as to maintain the flatness of the sprayed film; during the spraying process, after each droplet of the solution completely covers the hemispherical surface, the entire hemispherical surface is purged with 5 MPa high-speed nitrogen to form a relatively dry film;

[0115] (d) annealing the hemispherical substrate sprayed with the perovskite wet film obtained in step (c) at 120° C. for 10 minutes, then at 140° C. for 30 minutes, and finally at 170° C. for 60 minutes, maintaining dark conditions during the annealing process, and finally obtaining a perovskite film with a thickness of 12 μm;

[0116] 5. Deposit a hole transport layer onto the surface of the perovskite film, the steps are as follows:

[0117] (a) Purchased poly[bis(4-phenyl)(2,4,6-trimethylphenyl)amine] (PTAA) and toluene were prepared into a hole transport layer solution with a PTAA concentration of 0.1 mg / mL;

[0118] (b) adding 400 μL of the hole transport layer solution obtained in step (a) into a pneumatic spray gun of model HD180 with a nozzle diameter of 0.2 mm;

[0119] (c) Fix the hemispherical substrate coated with perovskite on a heating platform at 80°C, and connect the pneumatic spray gun in step (b) to an air compressor with an output pressure of 1.5MPa. The spraying time is determined by the total spraying volume. The spraying rate is 0.13mL / min, and the hemispherical substrate is sprayed to obtain a wet perovskite film on the outer surface of the hemisphere; during the spraying process, the hemispherical substrate is kept rotating and translating at a rotation speed of about 0.25r / min and a translation speed of 10cm / s. Each time the droplets of the solution completely cover the surface, the entire surface is purged with 5MPa high-speed nitrogen to form a relatively dry film; when the solution is exhausted, the hemisphere of the film is annealed at 100°C for 10 minutes, and the thickness of the obtained hole transport layer is 10nm;

[0120] 6. Vacuum evaporation is used to evaporate metal Cr onto the surface of the hole transport layer as an anode with a thickness of 8 nm, thereby preparing the narrow-band light detector with wide-angle detection and imaging capability of the present invention, the structure of which is hemispherical substrate / Cr / SnO2 / PEA2FA3Pb4I2Br 11 / PTAA / Cr.

[0121] Embodiment 5:

[0122] 1. Select a hemispherical substrate with a diameter of 0.8 cm (made of ordinary glass, available from commercial channels), ultrasonically clean it in ultrapure water, acetone and isopropanol for 15 minutes respectively, and then dry it;

[0123] 2. Vacuum evaporation was used to deposit metal Cr onto the surface of the hemispherical substrate as a cathode with a thickness of 13 nm. The surface of the metal Cr was then treated with UV-ozone for 20 minutes and then with plasma for 5 minutes.

[0124] 3. Deposit an electron transport layer on the cathode surface

[0125] (a) diluting the purchased SnO2 aqueous solution with ultrapure water to prepare an electron transport layer solution with a SnO2 concentration of 0.1%wt;

[0126] (b) adding 600 μL of the electron transport layer solution obtained in step (a) into a pneumatic spray gun of model HD180 with a nozzle diameter of 0.2 mm;

[0127] (c) placing a hemispherical substrate with a cathode on the surface on a 65°C heating table, and connecting the pneumatic spray gun in step (b) to an air compressor, with an output pressure of 2MPa and a spraying rate of 0.12mL / min, to spray the electron transport layer solution onto the cathode surface; during the spraying process, the rotation and translation of the hemispherical substrate are maintained at a rotation speed of 0.25r / min and a translation speed of 15cm / s, so as to maintain the flatness of the sprayed film; during the spraying process, after each droplet of the solution completely covers the hemispherical surface, the entire hemispherical surface is purged with 5MPa high-speed nitrogen to form a dry film; when the solution is exhausted, the film is annealed at 170°C for 30 minutes, and then subjected to UV-ozone treatment for 20 minutes, so as to obtain an electron transport layer with a thickness of 10nm on the cathode surface;

[0128] 4. The PEA2FA3Pb4I5Br8 perovskite film is deposited on the surface of the electron transport layer, and the steps are as follows:

[0129] (a) Formamidine hydrohalide (FAI), lead halide (PbBr2), phenylethylamine hydrohalide (PEAI) and methylamine hydrochloride (MACl) are prepared into a 0.5M (relative to lead ions) precursor solution according to the molar ratio of 3:4:2:1.2, and the solvent is a mixture of acetonitrile (ACN) and N,N-dimethylformamide (DMF) in a volume ratio of 2:3, and the solution is controlled to completely dissolve the perovskite powder;

[0130] (b) adding 1500 μL of the precursor solution prepared in step (a) into a pneumatic spray gun of model HD180 with a nozzle diameter of 0.2;

[0131] (c) placing a hemispherical substrate with an electron transport layer deposited on the surface on a heating platform at 100° C., connecting the pneumatic spray gun in step (b) to an air compressor with an output pressure of 2 MPa, spraying the precursor solution onto the surface of the electron transport layer at a spraying rate of 0.15 mL / min; during the spraying process, the hemispherical substrate is kept rotating and translating at a rotation speed of 0.25 r / min and a translation speed of 10 cm / s, so as to maintain the flatness of the sprayed film; during the spraying process, after each droplet of the solution completely covers the hemispherical surface, the entire hemispherical surface is purged with 5 MPa high-speed nitrogen to form a dry film;

[0132] (d) annealing the hemispherical substrate sprayed with the perovskite wet film obtained in step (c) at 120° C. for 10 minutes, then at 140° C. for 30 minutes, and finally at 170° C. for 60 minutes, maintaining dark conditions during the annealing process, and finally obtaining a perovskite film with a thickness of 12 μm;

[0133] 5. Deposit a hole transport layer onto the surface of the perovskite film, the steps are as follows:

[0134] (a) Purchased poly[bis(4-phenyl)(2,4,6-trimethylphenyl)amine] (PTAA) and toluene were prepared into a hole transport layer solution with a PTAA concentration of 0.1 mg / mL;

[0135] (b) adding 400 μL of the hole transport layer solution obtained in step (a) into a pneumatic spray gun of model HD180 with a nozzle diameter of 0.2 mm;

[0136] (c) Fix the hemispherical substrate coated with perovskite on a heating platform at 80°C, and connect the pneumatic spray gun in step (b) to an air compressor with an output pressure of 1.5MPa. The spraying time is determined by the total spraying volume. The spraying rate is 0.13mL / min, and the hemispherical substrate is sprayed to obtain a wet perovskite film on the outer surface of the hemisphere; during the spraying process, the hemispherical substrate is kept rotating and translating, with a rotation speed of about 0.25r / min and a translation speed of 10cm / s. Each time the droplets of the solution completely cover the surface, the entire surface is purged with 5MPa high-speed nitrogen to form a surface-dried film; when the solution is exhausted, the hemisphere of the film is annealed at 100°C for 10 minutes, and the thickness of the obtained hole transport layer is 10nm;

[0137] 6. Metal Cr is evaporated onto the surface of the hole transport layer by vacuum evaporation as an anode with a thickness of 8 nm, thereby preparing the narrow-band light detector with wide-angle detection and imaging capability described in the present invention, with a structure of hemispherical substrate / Cr / SnO2 / PEA2FA3Pb4I5Br8 / PTAA / Cr.

[0138] Example 6

[0139] The prepared hemispherical substrate / Cr / PEDOT:PSS / PEA2FA3Pb4I 13 / C 60 The anode and cathode of the / BCP / Cr photodetector (Example 2) were connected to a current source meter and the voltage-current density correlation was measured under 820nm monochromatic light of different illumination intensities. Figure 4 (a) is the schematic diagram of the test system. Figure 4 (b) Cr / PEDOT:PSS / PEA2FA3Pb4I 13 / C 60 Voltage-current density diagram of the / BCP / Cr photodetector under 820nm wavelength monochromatic light at different light intensities. The photodetector exhibits good self-voltage supply behavior and light response behavior.

[0140] Example 7

[0141] The prepared hemispherical substrate / Cr / PEDOT:PSS / PEA2FA3Pb4I 13 / C 60 The anode and cathode of the / BCP / Cr photodetector (Example 2) are connected to an oscilloscope (MDO3000) with wires and placed under monochromatic light of a certain light intensity. A signal trigger (RIGOL DG1022Z) transmits a square wave signal to the monochromatic light, so that the monochromatic light outputs a square wave signal through the oscilloscope, and an image of the current signal output by the device receiving the square wave signal is displayed to determine the device's response capability to different light colors.

[0142] Figure 5 PEA2FA3Pb4I 13 Normalized switching signal waveforms of the perovskite hemispherical device at different wavelengths. It can be seen that there is a good switching signal at the response wavelength (820nm), and there is almost no signal at the non-response wavelength (532nm), indicating that the photodetector prepared by the present invention exhibits a good wavelength selective response.

[0143] Example 8

[0144] 1. A flat substrate (made of ordinary glass, with dimensions of 1.5×1.5×0.2 cm) was ultrasonically cleaned in ultrapure water, acetone, and isopropanol for 15 minutes each, and then dried in an oven;

[0145] 2. Vacuum evaporation was used to deposit metal Cr onto the surface of the hemispherical substrate as an anode with a thickness of 12 nm. The surface of the metal Cr was then treated with UV-ozone for 20 minutes and then with plasma for 5 minutes.

[0146] 3. Deposit a hole transport layer on the anode surface

[0147] (a) diluting a poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonic acid) (PEDOT:PSS) aqueous solution with ultrapure water to obtain a hole transport layer solution with a PEDOT:PSS concentration of 0.1% wt;

[0148] (b) adding 600 μL of the hole transport layer solution in step (a) into a pneumatic spray gun of model HD180 with a nozzle diameter of 0.2 mm;

[0149] (c) placing a flat substrate with an anode on the surface thereof on a heating platform at 60° C., connecting the pneumatic spray gun in step (b) to an air compressor, with an output pressure of 1.5 MPa and a spraying rate of 0.15 mL / min, spraying the hole transport layer solution onto the surface of the anode, and during the spraying process, maintaining the translation of the flat substrate at a translation speed of 10 cm / s, thereby maintaining the flatness of the sprayed film; during the spraying process, after each droplet of the solution completely covers the surface of the hemisphere, blowing the entire surface of the flat substrate with 5 MPa of high-speed nitrogen gas to form a relatively dry film; after the solution is consumed, the film is annealed at 170° C. for 30 minutes, thereby obtaining a hole transport layer with a thickness of 10 nm on the surface of the anode;

[0150] (4) Deposition of PEA2FA3Pb4I on the surface of the hole transport layer 13 Perovskite thin film

[0151] (a) Formamidine hydrohalide (FAI), lead halide (PbI2), phenylethylamine hydrohalide (PEAI) and methylamine hydrochloride (MACl) are prepared in a ratio of 3:4:2:1.6 to form a precursor solution with a lead ion concentration of 0.6 M, and the solvent is a mixed solvent of acetonitrile (ACN) and N,N-dimethylformamide (DMF), or a mixed solvent of ethylene glycol methyl ether (2-Me) and N,N-dimethylformamide (DMF), and the volume ratio of acetonitrile (ACN) to N,N-dimethylformamide (DMF) is 1:1;

[0152] (b) adding 1500 μL of the precursor solution prepared in step (a) into a pneumatic spray gun with a nozzle model HD180 and a diameter of 0.2 mm;

[0153] (c) placing a hemispherical substrate with a hole transport layer deposited on the surface on a heating platform at 100° C., connecting the pneumatic spray gun in step (b) to an air compressor with an output pressure of 1.5 MPa, spraying the precursor solution onto the surface of the hole transport layer at a spraying rate of 0.15 mL / min; during the spraying process, the rotation and translation of the planar substrate are maintained at a rotation speed of 0.25 r / min and a translation speed of 10 cm / s, so as to maintain the flatness of the sprayed film; during the spraying process, after each droplet of the solution completely covers the surface of the substrate, the entire hemispherical surface is purged with 5 MPa high-speed nitrogen to form a relatively dry film;

[0154] (d) annealing the hemispherical substrate obtained in step (c) at 120° C. for 10 minutes, then at 160° C. for 30 minutes, and finally at 170° C. for 60 minutes, maintaining dark conditions during the annealing process, thereby obtaining a perovskite film with a thickness of 10 μm;

[0155] (5) The purchased fullerene (C 60) is evaporated onto the surface of the perovskite film to obtain an electron transport layer with a thickness of 15 nm;

[0156] (6) depositing purchased 2,9-dimethyl-4,7-biphenyl-1,10-phenanthroline (BCP) onto the surface of the electron transport layer by vacuum evaporation to obtain a buffer layer with a thickness of 6 nm;

[0157] (7) Vacuum evaporation was used to evaporate metal Cr onto the surface of the buffer layer as a cathode with a thickness of 10 nm; thus, a planar substrate / Cr / PEDOT:PSS / PEA2FA3PbI 13 / C 60 / BCP / Cr photodetector.

[0158] PEA2FA3Pb4I prepared in Example 2 13 The perovskite hemispherical device and the planar device prepared in this embodiment are connected with wires respectively. With the distance from the light source to the center of the device as the radius and the center of the device as the dot, the position of the light source is changed along the semicircle, and the electrical signal at each position is measured and recorded by the current source meter (when the light source irradiates the device vertically, the incident light angle is 0 degrees; when the light source irradiates the device horizontally, the incident light angle is 90 degrees).

[0159] Figure 6 (a) is the schematic diagram of the angle response test system. Figure 6 (b) is the response range curve of the planar detector and the hemispherical detector to the incident angle of monochromatic light; it can be seen that the hemispherical light detector has a good response capability to incident light of different angles, and the hemispherical device exhibits extremely high wide-angle detection capability. Under point light sources of various angles, the response capability is almost unchanged, and the corresponding angle can reach (-90 degrees to +90 degrees); while the response capability of the planar device is seriously dependent on the incident light angle.

[0160] Example 9

[0161] Four hemispherical photodetectors with different halogen X (X=I, Br) ratios were tested for their ability to respond to light of different wavelengths. Ultimately, a photodetector was obtained that could control the device's selectivity to different light colors by adjusting the halogen ratio of the middle layer perovskite.

[0162] The corresponding relationship between the device structure and the central response wavelength is

[0163] Cr / PEDOT:PSS / PEA2FA3Pb4I 13 / C 60 / BCP / Cr(820nm),

[0164] Cr / SnO2 / PEA2FA3Pb4I5Br8 / PTAA / Cr(660nm),

[0165] Cr / SnO2 / PEA2FA3Pb4I2Br 11 / PTAA / Cr(600nm),

[0166] Cr / SnO2 / PEA2FA3Pb4Br 13 / PTAA / Cr(550nm),

[0167] Figure 7 (a) is a schematic diagram of the test system for testing the device's ability to respond to light of different wavelengths. It is measured by external quantum efficiency (EQE); in the figure, the xenon light source passes through a monochromator and a chopper to output monochromatic light with a certain frequency to illuminate the detector. The current signal generated by the detector is amplified by the preamplifier and converted into a voltage signal. The same frequency signal is amplified again by the phase-locked amplifier and input into the computer. The ratio of the current density generated by the detector to the photon density irradiating the detector is calculated to calculate the quantum efficiency. The quantum efficiency of different wavelengths is used to measure the device's response ability to each wavelength (EQE).

[0168] Figure 7 (b) EQE diagrams corresponding to the above four device structures, with the horizontal axis being the wavelength and the vertical axis being the normalized EQE. Its half-height width is ~20nm. This figure shows that each device can only specifically respond to light signals with wavelengths near its corresponding central wavelength, and has almost no response to other wavelengths. This shows that the device exhibits the ability to recognize narrow-band light colors. The device only responds to light of a specific color, and at the same time, we control the ratio of X-type I and Br in the main perovskite material to controllably adjust the wavelength position of this specific recognition of the device.

[0169] Example 10

[0170] Imaging system construction of narrow-band light detector for wide-angle detection:

[0171] (a) Fix a 820nm monochromatic LED light source on the XY two-dimensional displacement platform, and the light source power is 3W.

[0172] (b) connecting the two-dimensional displacement platform described in (a) to a computer to control its movement, with a moving unit distance of 500 μm / step;

[0173] (c) The LED light source described in (a) is connected to a function generator (RIGOL DG1022Z) to output a square wave signal with a frequency of 70 Hz to light up the LED light source. At the same time, the signal is connected to a phase-locked amplifier (SR830) to make the electrical signal converted by the device and the electrical signal generated by the function generator as a reference of the same frequency, as shown in FIG. Figure 8 As shown;

[0174] (d) The object to be measured is placed on a glass platform below the light source, and the hemispherical light detector is placed below the glass platform;

[0175] (e) Adjust the angle of the hemispherical light detector described in step (d) as follows: Fig. 9 As shown. Compared with the plane light detector, the hemispherical light detector can image objects at extreme angles. The angle of the object relative to the detector can be adjusted by changing the relative angle between the plane where the hemispherical light detector base is located and the light source and the object. Here we choose objects that occupy the imaging range of the detector from -8 degrees to +30 degrees and the imaging range of -52 degrees to -90 degrees, as shown in Fig.10 As shown. The photodetector is connected to the preamplifier (SR570), the lock-in amplifier (SR830) and the computer;

[0176] (f) Using a computer to read data from the system and obtain imaging results. Imaging device type: Cr / PEDOT:PSS / PEA2FA3Pb4I 13 / C 60 / BCP / Cr.

[0177] Fig. 9 Schematic diagram of the object occupancy angle, where θ1 and θ2 are used to calculate the object's incident angle. Fig.10 The angular objects used for imaging occupy angles of -52 to -90 degrees and -8 to +30 degrees. The same two angular ranges of imaging are also used in the planar light detector. The imaging results are Fig.11 shown. Fig.11 (a) Planar photodetector imaging, the object occupies an angle ranging from -8 degrees to +30 degrees; Fig.11 (b) Planar photodetector imaging, the object occupies an angle from -90 degrees to -52 degrees; Fig.11 (c) Hemispherical light detector imaging, the object occupies an angle from -8 degrees to +30 degrees; Fig.11 (d) Hemispherical light detector imaging, the object occupies an angle from -90 degrees to -52 degrees. Fig.11 This shows that the imaging range of the hemispherical device is much larger than that of the flat detector, showing the ability of wide-angle detection. Especially for grazing angle imaging (-90 degrees), flat imaging is significantly limited, while the hemispherical detector can still maintain the imaging effect.

[0178] Embodiment 11

[0179] Imaging system construction of narrow-band light detector for wide-angle detection:

[0180] (a) A 550nm monochromatic LED light source with a power of 3W is fixed on the XY two-dimensional displacement platform.

[0181] (b) connecting the two-dimensional displacement platform described in (a) to a computer to control its movement, with a moving unit distance of 500 μm / step;

[0182] (c) The LED light source described in (a) is connected to a function generator (RIGOL DG1022Z) to output a square wave signal with a frequency of 70 Hz to light up the LED light source. At the same time, the signal is connected to a phase-locked amplifier (SR830) to use the electrical signal converted by the device as a reference with the electrical signal generated by the function generator;

[0183] (d) The object to be measured is placed on a glass platform below the light source, and the hemispherical light detector is placed below the glass platform;

[0184] (e) Adjust the angle of the hemispherical light detector described in step (d) so that the angle of the hemispherical light detector is collinear with the light source object at an angle of 0 degrees. The light detector is connected to a preamplifier (SR570), a lock-in amplifier (SR830) and a computer.

[0185] The device structure is Cr / SnO2 / PEA2FA3Pb4Br 13 The hemispherical photodetector of / PTAA / Cr was placed under the glass platform and imaged using an imaging system.

[0186] Example 12

[0187] Imaging system construction of narrow-band light detector for wide-angle detection:

[0188] (a) A 600nm monochromatic LED light source with a power of 3W is fixed on the XY two-dimensional displacement platform.

[0189] (b) connecting the two-dimensional displacement platform described in (a) to a computer to control its movement, with a moving unit distance of 500 μm / step;

[0190] (c) The LED light source described in (a) is connected to a function generator (RIGOL DG1022Z) to output a square wave signal with a frequency of 70 Hz to light up the LED light source. At the same time, the signal is connected to a phase-locked amplifier (SR830) to use the electrical signal converted by the device as a reference with the electrical signal generated by the function generator;

[0191] (d) The object to be measured is placed on a glass platform below the light source, and the hemispherical light detector is placed below the glass platform;

[0192] (e) Adjust the angle of the hemispherical light detector described in step (d) so that the angle of the hemispherical light detector is collinear with the light source object at an angle of 0 degrees. The light detector is connected to a preamplifier (SR570), a lock-in amplifier (SR830) and a computer.

[0193] The device structure is Cr / SnO2 / PEA2FA3Pb4I2Br 11 The hemispherical photodetector of / PTAA / Cr was placed under the glass platform and imaged using an imaging system.

[0194] Example 13

[0195] Imaging system construction of narrow-band light detector for wide-angle detection:

[0196] (a) A 660nm monochromatic LED light source with a power of 3W is fixed on the XY two-dimensional displacement platform.

[0197] (b) connecting the two-dimensional displacement platform described in (a) to a computer to control its movement, with a moving unit distance of 500 μm / step;

[0198] (c) The LED light source described in (a) is connected to a function generator (RIGOL DG1022Z) to output a square wave signal with a frequency of 70 Hz to light up the LED light source. At the same time, the signal is connected to a phase-locked amplifier (SR830) to use the electrical signal converted by the device as a reference with the electrical signal generated by the function generator;

[0199] (d) The object to be measured is placed on a glass platform below the light source, and the hemispherical light detector is placed below the glass platform;

[0200] (e) Adjust the angle of the hemispherical light detector described in step (d) so that the angle of the hemispherical light detector is collinear with the light source object at an angle of 0 degrees. The light detector is connected to a preamplifier (SR570), a lock-in amplifier (SR830) and a computer.

[0201] The hemispherical photodetector with the device structure of Cr / SnO2 / PEA2FA3Pb4I5Br8 / PTAA / Cr was placed under the glass platform and imaged using an imaging system.

[0202] Fig.12 The imaging of the narrow-band light detector with different response wavelengths prepared by adjusting the halogen is the response imaging under the monochromatic light corresponding to its center. The corresponding response wavelengths are 550nm, 600nm, 660nm and the summation diagram obtained by superposition of light colors. Such imaging will greatly reduce the influence of light from other colors on the imaging. Since the device can only image light of a certain range of colors around its central wavelength, and has almost no response ability to light in other bands. Therefore, only light sources with corresponding light colors can be used to meet the imaging requirements of the device, and light sources with other light colors cannot make the device respond and form an image. This imaging method selectively filters out the interference of light of other colors on the imaging process, and at the same time can select a certain color of light for imaging according to the purpose.

[0203] Fig.12 (a) 550nm monochromatic light imaging device structure is hemispherical substrate / Cr / SnO2 / PEA2FA3Pb4Br 13 / PTAA / Cr; Fig.12 (b) 600nm monochromatic light imaging device structure is hemispherical substrate / Cr / SnO2 / PEA2FA3Pb4I2Br 11 / PTAA / Cr; Fig.12 (c) The structure of the 660nm monochromatic light imaging device is hemispherical substrate / Cr / SnO2 / PEA2FA3Pb4I5Br8 / PTAA / Cr; Fig.12 (d) Superposition of different monochromatic imaging results. This type of imaging can more realistically represent the object. At the same time, each monochromatic image can be of great help in later image processing. This imaging result is helpful for analyzing the object image in terms of light color wavelength.

[0204] In summary, the optical detector proposed in the present invention has broad application prospects in wide-angle and narrow-band detection.

Claims

1. A method for preparing a narrow-band light detector with wide-angle detection and imaging capability, which is sequentially composed of a hemispherical substrate, an anode, a hole transport layer, a perovskite film, an electron transport layer, a buffer layer and a cathode, and the steps are as follows: (1) Select a hemispherical substrate with a diameter of 0.8-2 cm, ultrasonically clean it in ultrapure water, acetone, and isopropanol for 10-20 minutes respectively, and then dry it; (2) Vacuum evaporation was used to deposit metal Cr onto the surface of the hemispherical substrate as an anode with a thickness of 8 to 15 nm. The metal Cr surface was then treated with UV-ozone for 15 to 30 minutes and then with plasma for 5 to 10 minutes. (3) Deposition of hole transport layer on the anode surface (a) diluting the poly(3,4-ethylenedioxythiophene)-poly(styrene sulfonic acid) aqueous solution with ultrapure water to obtain a hole transport layer solution having a poly(3,4-ethylenedioxythiophene)-poly(styrene sulfonic acid) concentration of 0.05-0.2% wt; (b) Add 400-1000 μL of the hole transport layer solution in step (a) into a pneumatic spray gun with a nozzle diameter of 0.2-0.5 mm; (c) placing the hemispherical substrate with the anode prepared on the surface on a hot stage at 60-80°C, connecting the pneumatic spray gun in step (b) to an air compressor, with an output pressure of 1-3 MPa and a spraying rate of 0.10-0.3 mL / min, spraying the hole transport layer solution onto the surface of the anode. During the spraying process, the hemispherical substrate is rotated and translated at a rotation speed of 0.20-0.30 r / min and a translation speed of 5-20 cm / s, so as to maintain the flatness of the sprayed film. During the spraying process, after each droplet of the solution completely covers the hemispherical surface, the entire hemispherical surface is purged with high-speed nitrogen at 4-7 MPa to form a relatively dry film. When the solution is exhausted, the film is annealed at 160-180°C for 20-40 minutes, so as to obtain a hole transport layer with a thickness of 10-100 nm on the surface of the anode. (4) Deposition of PEA2FA3Pb4X on the surface of the hole transport layer 13 Perovskite film, X = Br, I or Br and I, the sum of their subscripts is 13 (a) Formamidine hydrohalide, lead halide, phenylethylamine hydrohalide and methylamine hydrochloride are prepared according to PEA2FA3Pb4X 13 The molecular formula ratio is configured into a precursor solution with a lead ion concentration of 0.4-0.6 M, the solvent is a mixed solvent of acetonitrile and N,N-dimethylformamide, or a mixed solvent of ethylene glycol methyl ether and N,N-dimethylformamide, and the volume ratio of acetonitrile or ethylene glycol methyl ether to N,N-dimethylformamide is 1:1-3; (b) adding 500-2000 μL of the precursor solution prepared in step (a) into a pneumatic spray gun with a nozzle diameter of 0.2-0.5 mm; (c) placing a hemispherical substrate with a hole transport layer deposited on the surface on a heating platform at 80-120°C, connecting the pneumatic spray gun in step (b) to an air compressor with an output pressure of 1-3 MPa, spraying the precursor solution onto the surface of the hole transport layer at a spraying rate of 0.1-0.3 mL / min; during the spraying process, the hemispherical substrate is rotated and translated at a rotation speed of 0.20-0.30 r / min and a translation speed of 5-20 cm / s, so as to maintain the flatness of the sprayed film; during the spraying process, after each droplet of the solution completely covers the hemispherical surface, the entire hemispherical surface is purged with high-speed nitrogen at 4-7 MPa to form a relatively dry film; (d) annealing the hemispherical substrate obtained in step (c) at 80-120° C. for 8-15 minutes, then annealing at 120-140° C. for 20-40 minutes, and finally annealing at 160-170° C. for 60-90 minutes, maintaining dark conditions during the annealing process, thereby obtaining a perovskite film with a thickness of 2-40 μm; (5) Fullerene (C 60 ) Evaporation onto the surface of the perovskite film to obtain an electron transport layer with a thickness of 15-30 nm; (6) Vacuum evaporation was used to deposit 2,9-dimethyl-4,7-biphenyl-1,10-phenanthroline onto the surface of the electron transport layer to obtain a buffer layer with a thickness of 4 to 10 nm; (7) Metal Cr is evaporated onto the surface of the buffer layer by vacuum evaporation to serve as a cathode with a thickness of 8 to 15 nm; thereby, a structure with wide-angle detection and imaging capability is prepared: hemispherical substrate / Cr / PEDOT:PSS / PEA2FA3Pb4X 13 / C 60 / BCP / Cr narrowband photodetector.

2. A method for preparing a narrow-band light detector with wide-angle detection and imaging capability, comprising a hemispherical substrate, a cathode, an electron transport layer, a perovskite film, a hole transport layer and an anode, wherein the steps are as follows: (1) Select a hemispherical substrate with a diameter of 0.8-2 cm, ultrasonically clean it in ultrapure water, acetone, and isopropanol for 10-20 minutes respectively, and then dry it; (2) Vacuum evaporation was used to deposit metal Cr onto the surface of the hemispherical substrate as a cathode with a thickness of 8 to 15 nm. The metal Cr surface was then treated with UV-ozone for 15 to 30 minutes and then with plasma for 5 to 10 minutes. Deposition of electron transport layer on cathode surface (a) diluting the SnO2 aqueous solution with ultrapure water to prepare an electron transport layer solution with a SnO2 concentration of 0.05-0.1%wt; (b) adding 400-1000 μL of the electron transport layer solution obtained in step (a) into a pneumatic spray gun with a nozzle diameter of 0.2-0.5 mm; (c) placing the hemispherical substrate with the cathode prepared on the surface on a heating table at 60-80°C, and connecting the pneumatic spray gun in step (b) to an air compressor, with an output pressure of 1-3 MPa and a spraying rate of 0.10-0.20 mL / min, to spray the electron transport layer solution onto the cathode surface; during the spraying process, the rotation and translation of the hemispherical substrate are maintained at a rotation speed of 0.20-0.30 r / min and a translation speed of 5-20 cm / s, so as to maintain the flatness of the sprayed film; during the spraying process, after each droplet of the solution completely covers the hemispherical surface, the entire hemispherical surface is purged with 4-7 MPa high-speed nitrogen to form a relatively dry film; when the solution is exhausted, the film is annealed at 160-180°C for 20-40 minutes, and then subjected to UV-ozone treatment for 15-30 minutes, so as to obtain an electron transport layer with a thickness of 10-100 nm on the cathode surface; (4) Deposition of PEA2FA3Pb4X on the surface of the electron transport layer 13 Perovskite film, X = Br, I or Br and I, the sum of their subscripts is 13 (a) Formamidine hydrohalide, lead halide, phenylethylamine hydrohalide and methylamine hydrochloride are prepared according to PEA2FA3Pb4X 13 The molecular formula ratio is configured into a precursor solution with a lead ion concentration of 0.4-0.6 M, the solvent is a mixed solvent of acetonitrile and N,N-dimethylformamide, or a mixed solvent of ethylene glycol methyl ether and N,N-dimethylformamide, and the volume ratio of acetonitrile or ethylene glycol methyl ether to N,N-dimethylformamide is 1:1-3; (b) adding 500-2000 μL of the precursor solution prepared in step (a) into a pneumatic spray gun with a nozzle diameter of 0.2-0.5 mm; (c) placing a hemispherical substrate with an electron transport layer deposited on the surface on a heating table at 80-120°C, connecting the pneumatic spray gun in step (b) to an air compressor with an output pressure of 1-3 MPa, spraying the precursor solution onto the surface of the electron transport layer at a spraying rate of 0.1-0.3 mL / min; during the spraying process, the rotation and translation of the hemispherical substrate are maintained at a rotation speed of 0.20-0.30 r / min and a translation speed of 5-20 cm / s, so as to maintain the flatness of the sprayed film; during the spraying process, after each droplet of the solution completely covers the hemispherical surface, the entire hemispherical surface is purged with high-speed nitrogen at 4-7 MPa to form a dry film; (d) annealing the hemispherical substrate obtained in step (c) at 80-120°C for 8-15 minutes, then annealing at 120-140°C for 20-40 minutes, and finally annealing at 160-170°C for 60-90 minutes, maintaining dark conditions during the annealing process; thereby obtaining a perovskite film with a thickness of 2-40 μm; The hole transport layer is deposited on the surface of the perovskite film, and the steps are as follows: (a) poly[bis(4-phenyl)(2,4,6-trimethylphenyl)amine] and toluene are prepared into a hole transport layer solution with a poly[bis(4-phenyl)(2,4,6-trimethylphenyl)amine] concentration of 0.05-0.2 mg / mL; (b) adding 400-1000 μL of the hole transport layer solution obtained in step (a) into a pneumatic spray gun with a nozzle diameter of 0.2-0.5 mm; (c) Fixing the hemispherical substrate with the perovskite film on the surface on a heating platform at 60-80°C, and connecting the pneumatic spray gun in step (b) to an air compressor, with an output pressure of 1-3 MPa and a spraying rate of 0.10-0.20 mL / min, spraying the hole transport layer solution onto the perovskite film. During the spraying process, the hemispherical substrate is rotated and translated at a rotation speed of 0.20-0.30 r / min and a translation speed of 5-20 cm / s, so as to maintain the flatness of the sprayed film. During the spraying process, after each droplet of the solution completely covers the hemispherical surface, the entire hemispherical surface is purged with high-speed nitrogen at 4-7 MPa to form a relatively dry film. When the solution is exhausted, the film is annealed at 90-110°C for 5-15 minutes to obtain a hole transport layer with a thickness of 10-100 nm. (6) Metal Cr was evaporated onto the surface of the hole transport layer by vacuum evaporation to serve as the anode with a thickness of 8-15 nm, thereby preparing a hemispherical substrate / Cr / SnO2 / PEA2FA3Pb4X 13 Narrowband photodetector of / PTAA / Cr.

3. A narrow-band light detector with wide-angle detection and imaging capability, characterized in that: Prepared by the method described in claim 1 or 2.

4. An imaging method of a narrow-band light detector with wide-angle detection and imaging capability, the steps of which are as follows: (a) A monochromatic LED light source with a central wavelength adjustable between 400 and 900 nm is fixed on an XY two-dimensional displacement platform, and the light source power is 3 to 10 W; (b) Connect the XY two-dimensional displacement stage in step (a) to a computer to control its movement, with the unit distance of movement being 200-500 μm / step; (c) connecting the LED light source in step (a) to a function generator, the function generator outputting a square wave signal with a frequency of 20 to 90 Hz; (d) placing the object to be measured on a glass platform below the LED light source, and placing the narrow-band light detector described in claim 3 below the glass platform; (e) adjusting the angle of the narrowband light detector described in step (d) so that it presents a certain angle with the imaging system, and then connecting the hemispherical narrowband light detector to the preamplifier, the phase-locked amplifier and the computer; in the experiment, the function generator outputs a square wave signal to the light source and has the same frequency as the phase-locked amplifier, the device receives the light signal and converts it into a current signal and outputs it to the preamplifier, the preamplifier converts the current signal into a voltage signal and amplifies it and transmits it to the phase-locked amplifier, the phase-locked amplifier further amplifies the voltage information from the preamplifier and the signal with the same frequency as the function generator and transmits it to the computer; each time the stepper motor moves one step, a data point is read to form a data matrix; (f) The voltage data matrix is ​​read by a computer and the imaging results are finally obtained through MATLAB software.

Images