Detection method and detection system for fluorescence quantum yield

Abstract

The invention relates to a fluorescence quantum yield detection method and system, and the method comprises the steps: S1, placing a blank support plate at a mounting position of an integrating sphere, arranging an optical filter in front of a receiving end of a detector, and calculating the integral area Psample 1 of the blank support plate in a fluorescence signal wavelength interval, and the integral area Plaser1 of the blank carrier plate at the laser wavelength; s2, arranging the sample at the mounting position of an integrating sphere, and calculating the integral area Psample < 2 > of the sample in the fluorescence signal wavelength interval and the integral area Plaser2 of the sample at the laser wavelength; and S3, substituting the calculation result into a fluorescence quantum yield calculation formula: QY = (Psample < 2 >-Psample < 1 >) / (Plaser1-Plaser2). According to the detection method for the fluorescence quantum yield, the integral area ratio is directly calculated, and the problem that the laser intensity is too high is avoided. Even if the laser scattering intensity is increased, accurate integration can be achieved as long as the detector can distinguish the wavelength intervals of the laser peak and the fluorescence peak, and the detection accuracy of the fluorescence quantum yield of the sample is improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of photovoltaic technology, in particular to a method and system for detecting fluorescence quantum yield. BACKGROUND

[0002] Solution-processed perovskite thin films inevitably produce defects during preparation, so monitoring the quality of the thin film is very important for large-area production and preparation process. Photoluminescence fluorescence quantum yield is an effective method for characterizing and quantifying the quality monitoring of perovskite film layer and other perovskite film layers during preparation. During the preparation of perovskite thin film and subsequent interface layer, the quasi-Fermi level splitting can be calculated by measuring the fluorescence quantum yield, so as to quantify the influence of each film layer material or preparation process on the performance of the battery.

[0003] The existing method usually uses an integrating sphere to collect the excitation light and fluorescence emission light of the sample, uses a detector to measure the incident light power and fluorescence emission power respectively, and at the same time deducts the reflection and transmission light of the sample, and finally calculates the fluorescence quantum yield by using the formula.

[0004] However, the existing detection method needs to further enhance the laser intensity to improve the luminescence intensity of the perovskite thin film for a sample with low fluorescence quantum yield. Since the scattering intensity of the laser will also increase, the detected laser intensity in the detector will exceed its detection upper limit, resulting in inaccurate data measured by the detector, and thus the calculated fluorescence quantum yield based on the detection data is not accurate. SUMMARY

[0005] Therefore, it is necessary to provide a method and system for detecting fluorescence quantum yield to solve the problem of inaccurate calculation of fluorescence quantum yield.

[0006] The present application provides a method for detecting fluorescence quantum yield, which comprises:

[0007] S1, placing a blank carrier plate at the installation position of an integrating sphere, placing a filter in front of the receiving end of a detector, calculating the integral area Psample1 of the blank carrier plate in the fluorescence signal wavelength interval, and the integral area Plaser1 of the blank carrier plate at the laser wavelength;

[0008] S2, placing a sample at the installation position of the integrating sphere, calculating the integral area Psample2 of the sample in the fluorescence signal wavelength interval, and the integral area Plaser2 of the sample at the laser wavelength;

[0009] S3, substituting the above calculation results into the fluorescence quantum yield calculation formula: QY=(Psample2-Psample1) / (Plaser1-Plaser2).

[0010] In one embodiment, step S1 comprises:

[0011] placing the blank carrier board at the installation position, measuring an actual spectral curve C2, comparing a factory spectral curve C1 of the detector with the actual spectral curve C2 to obtain a spectral responsivity S of the test system, S=C1 / C2;

[0012] placing the optical filter in front of the receiving end of the detector, measuring a filtered spectral curve C3, comparing the filtered spectral curve C3 with the actual spectral curve C2 to obtain a spectral transmittance T of the optical filter, T=C3 / C2;

[0013] when the laser is in an off state, testing a response of the blank carrier board to the laser in a dark state to obtain a dark state curve D1 of the blank carrier board;

[0014] when the laser is in an on state, exciting the blank carrier board by the laser, testing a signal curve L1 of the blank carrier board, and correcting the signal curve L1 of the blank carrier board to Ccontrol, Ccontrol=(L1-D1)*S*T;

[0015] integrating the Ccontrol curve in different wavelength intervals to obtain Psample1 and Plaser1.

[0016] In one embodiment, step S2 comprises:

[0017] placing the sample at the installation position of the integrating sphere;

[0018] when the laser is in an off state, testing a response of the sample to the laser in a dark state to obtain a dark state curve D2 of the sample;

[0019] when the laser is in an on state, exciting the sample by the laser, testing a signal curve L2 of the sample, and correcting the signal curve L2 of the sample to Csample, Csample=(L2-D2)*S*T;

[0020] integrating the Csample curve in different wavelength intervals to obtain Psample2 and Plaser2.

[0021] In one embodiment, the integrating sphere is connected to the receiving end of the detector through an optical fiber, and the step of placing the optical filter in front of the receiving end of the detector comprises:

[0022] placing the optical filter at an end of the optical fiber away from the detector; or,

[0023] The optical filter is arranged between the optical fiber and the detector.

[0024] In one embodiment, the optical filter is a long-pass filter, wherein the wavelength of the long-pass filter is greater than or equal to 600 nm and less than or equal to 700 nm; or

[0025] The optical filter is a wide-pass filter, wherein the wavelength of the wide-pass filter is greater than 100 nm.

[0026] In one embodiment, the blank carrier is made of a material with a refractive index greater than 1.5.

[0027] The present application also provides a system using any of the above-mentioned fluorescence quantum yield detection methods, wherein the fluorescence quantum yield detection system comprises:

[0028] Lasers;

[0029] Integrating sphere;

[0030] A detector and a controller in communication connection, the controller being configured to receive data information transmitted by the detector and calculate the fluorescence quantum yield based on the data information;

[0031] The filter is arranged in the integrating sphere and connected to the receiving end of the detector.

[0032] In one embodiment, the optical filter comprises a long-pass filter, wherein the wavelength of the long-pass filter is greater than or equal to 600 nm and less than or equal to 700 nm.

[0033] In one embodiment, the filter comprises a wide-pass filter, wherein the wavelength of the wide-pass filter is greater than 100 nm.

[0034] In one embodiment, the inner circumference of the integrating sphere includes a mounting position, an incident port is provided on the integrating sphere, and the incident port and the mounting position are spaced apart along the radial direction of the integrating sphere.

[0035] The detection method of the fluorescence quantum yield can selectively transmit the fluorescence signal wavelength interval and block the light at the laser wavelength by setting a filter before the receiving end of the detector, avoid the strong laser scattering light from entering the detector, thereby eliminating the interference of the fluorescence signal, and ensuring that the signal collected by the detector is mainly the real fluorescence of the sample. By calculating the integral area Psample1 of the blank carrier plate at the fluorescence signal wavelength interval, the integral area Plaser1 of the blank carrier plate at the laser wavelength, the integral area Psample2 of the sample at the fluorescence signal wavelength interval, and the integral area Plaser2 of the sample at the laser wavelength, the integral area ratio is directly calculated, which avoids the problem of too high laser intensity. Even if the laser scattering intensity increases, as long as the detector can distinguish the wavelength interval of the laser peak and the fluorescence peak, the integral can be accurately calculated, and the detection accuracy of the sample fluorescence quantum yield is improved. Moreover, by comparing the integral area difference (Psample2-Psample1 and Plaser1-Plaser2) of the blank carrier plate and the sample, the influence of the carrier plate reflection / transmission is automatically offset, the process is simplified, and the system error is reduced.

[0036] The detection system of the fluorescence quantum yield can selectively block the scattered light at the laser wavelength by setting a filter in the integrating sphere and connecting the filter to the receiving end of the detector, and only allow the fluorescence signal into the detector. The problem of detector overload caused by the increase of laser scattering intensity is solved, and the distortion of measurement data caused by laser noise interference is avoided. The detection system of the fluorescence quantum yield of the present application isolates the laser and fluorescence wavelengths by the filter, so that high laser intensity is not needed even in the low fluorescence quantum yield scenario, thereby avoiding the detector 300 from exceeding the detection upper limit due to laser scattering, and ensuring the accuracy of the fluorescence quantum yield calculation. BRIEF DESCRIPTION OF DRAWINGS

[0037] Figure 1 The overall flowchart of the detection method of the fluorescence quantum yield provided by the embodiment of the present application.

[0038] Figure 2 The flowchart of step S1 of the detection method of the fluorescence quantum yield provided by the embodiment of the present application.

[0039] Figure 3 The flowchart of step S2 of the detection method of the fluorescence quantum yield provided by the embodiment of the present application.

[0040] Figure 4 The structural schematic diagram of the detection system of the fluorescence quantum yield provided by the first embodiment of the present application.

[0041] Figure 5 The structural schematic diagram of the detection system of the fluorescence quantum yield provided by the second embodiment of the present application.

[0042] REFERENCE NUMERALS:

[0043] 100, laser;

[0044] 200, integrating sphere; 210, mounting position;

[0045] 300, detector;

[0046] 400, optical fiber;

[0047] 500, filter;

[0048] 600, controller. DETAILED DESCRIPTION

[0049] In order to make the above objectives, features and advantages of the present application more clear and easily understood, the specific embodiments of the present application will be described in detail below with reference to the accompanying drawings. In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present application. However, the present application can be practiced in a number of different ways without departing from the spirit thereof and it is understood that similar improvements can be made without departing from the scope of the present application. Therefore, the present application is not limited to the specific embodiments disclosed below.

[0050] In the description of the present application, it should be understood that, if there are terms such as "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. appear, these terms indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the purpose of facilitating the description of the present application and simplifying the description, and therefore cannot be understood as indicating or implying that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the present application.

[0051] In addition, if the terms "first", "second" appear, these terms are only for the purpose of description, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features referred to. Therefore, the features limited by "first", "second" can explicitly or implicitly include at least one of the features. In the description of the present application, if the term "a plurality of" appears, the meaning of "a plurality of" is at least two, for example, two, three, etc., unless otherwise specifically limited.

[0052] In the present application, unless specifically defined otherwise, if there is an appearance of the terms "installation", "connection", "link", "fixation" and the like, these terms should be interpreted in a broad sense. For example, it can be fixedly connected, or it can be detachably connected, or it can be integrated; it can be mechanically connected, or it can be electrically connected; it can be directly connected, or it can be indirectly connected through an intermediate medium; it can be the internal communication of two elements or the interaction relationship between two elements, unless otherwise specifically defined. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0053] In the present application, unless specifically defined otherwise, if there is an appearance of the terms "installation", "connection", "link", "fixation" and the like, these terms should be interpreted in a broad sense. For example, it can be fixedly connected, or it can be detachably connected, or it can be integrated; it can be mechanically connected, or it can be electrically connected; it can be directly connected, or it can be indirectly connected through an intermediate medium; it can be the internal communication of two elements or the interaction relationship between two elements, unless otherwise specifically defined. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0054] It should be noted that if an element is referred to as "fixed to" or "disposed on" another element, it can be directly on the other element or there can be a middle element. If an element is considered to be "connected" to another element, it can be directly connected to the other element or there can be a middle element. If present, the terms "vertical", "horizontal", "up", "down", "left", "right" and similar expressions used in the present application are for illustrative purposes only and do not represent the only implementation.

[0055] The present application provides a method for detecting fluorescence quantum yield, as shown in Figure 1 The method for detecting fluorescence quantum yield comprises:

[0056] S1, placing a blank carrier plate at the installation position 210 of the integrating sphere 200, calculating the integral area Psample1 of the blank carrier plate in the fluorescence signal wavelength interval, and the integral area Plaser1 of the blank carrier plate at the laser wavelength;

[0057] S2, placing a sample at the installation position 210 of the integrating sphere 200, calculating the integral area Psample2 of the sample in the fluorescence signal wavelength interval, and the integral area Plaser2 of the sample at the laser wavelength;

[0058] S3, the calculation result is substituted into the fluorescence quantum yield calculation formula: QY= (Psample2-Psample1) / (Plaser1-Plaser2).

[0059] The above-mentioned fluorescence quantum yield detection method can selectively transmit the fluorescence signal wavelength interval and block the light at the laser wavelength by arranging the optical filter 500 before the receiving end of the detector 300, avoid the strong laser scattering light from entering the detector 300, thereby eliminating the interference of the fluorescence signal, and ensuring that the signal collected by the detector 300 is mainly the real fluorescence of the sample. By calculating the integral area Psample1 of the blank carrier at the fluorescence signal wavelength interval, the integral area Plaser1 of the blank carrier at the laser wavelength, the integral area Psample2 of the sample at the fluorescence signal wavelength interval, and the integral area Plaser2 of the sample at the laser wavelength, the integral area ratio is directly calculated, which avoids the problem of too high laser intensity. Even if the laser scattering intensity increases, as long as the detector 300 can distinguish the wavelength interval of the laser peak and the fluorescence peak, accurate integration can be achieved, and the detection accuracy of the fluorescence quantum yield of the sample is improved. Moreover, by comparing the integral area difference (Psample2-Psample1 and Plaser1-Plaser2) of the blank carrier and the sample, the influence of the carrier reflection / transmission is automatically offset, the process is simplified, and the system error is reduced.

[0060] It should be noted that the fluorescence signal wavelength and the laser wavelength are set according to actual operation needs.

[0061] It should be noted that when calculating the fluorescence quantum yield, the detector 300 transmits the received information to the controller 600, and the controller 600 calculates according to the above-mentioned fluorescence quantum yield detection method.

[0062] In one embodiment, as shown in Figure 1 and Figure 2 , step S1 includes:

[0063] Place the blank carrier at the installation position 210, measure the actual spectrum curve C2, compare the factory spectrum curve C1 of the detector 300 with the actual spectrum curve C2, and obtain the spectral responsivity S of the test system, S=C1 / C2;

[0064] Arrange the optical filter 500 before the receiving end of the detector 300, measure the filtered spectrum curve C3, compare the filtered spectrum curve C3 with the actual spectrum curve C2, and obtain the spectral transmittance T of the optical filter 500, T=C3 / C2;

[0065] When the laser 100 is in an unopened state, test the response of the blank carrier to the laser 100 in a dark state, and obtain the dark curve D1 of the blank carrier;

[0066] When the laser 100 is in an open state, a blank carrier plate is excited by the laser 100, a signal curve L1 of the blank carrier plate is tested, and a signal curve of the corrected blank carrier plate is Ccontrol, Ccontrol=(L1-D1)*S*T.

[0067] The integral of the Ccontrol curve in different wavelength intervals is calculated to obtain Psample1 and Plaser1.

[0068] Since the response capability of the detector 300 to different wavelengths of light has inherent differences (such as quantum efficiency changes with wavelength), direct measurement will cause spectral intensity distortion. By comparing the factory spectral response curve C1 of the detector 300 with the actual measurement curve C2, the system spectral responsivity S=C1 / C2 is obtained. Through this correction step, the influence of the spectral response characteristics of the detector 300 itself on the measurement results can be eliminated, making the subsequent integral area calculation closer to the true optical power, thereby avoiding the QY calculation deviation caused by the nonlinear response of the detector 300.

[0069] By measuring the ratio of the filter spectral curve C3 to the actual spectral curve C2, the transmittance T=C3 / C2 of the optical filter 500 is obtained. Through the transmittance correction of the optical filter 500, the attenuation degree of the excitation light (such as the laser wavelength) by the optical filter 500 can be accurately calculated, so as to eliminate the interference of scattered excitation light in data processing and only keep the effective data in the wavelength interval of the fluorescent signal. For example, when a long-pass optical filter (600-700 nm) is selected, the scattered light of the laser wavelength (such as 400-500 nm) can be effectively blocked, ensuring that the signal received by the detector 300 is mainly fluorescent light, and improving the signal purity when detecting low QY samples.

[0070] By measuring the dark state curve D1 of the blank carrier plate, the dark state curve D1 can be subtracted, which can significantly improve the signal-to-noise ratio (SNR) and enable the detector 300 to accurately capture the fluorescent signal under low light intensity conditions. For example, when the fluorescent intensity of the sample is close to the noise level, dark state correction can prevent noise from being mistaken for fluorescent signal, thereby improving the reliability of integral area calculation and solving the problem of low QY sample detection error caused by noise interference in the prior art.

[0071] In summary, the present application forms a complete signal calibration system through the combination mechanism of "spectral responsivity correction + optical filter 500 transmittance correction + dark state response subtraction". Instead of relying on enhancing the intensity of the laser to improve the fluorescent signal, the signal extraction capability is enhanced through the correction algorithm, thereby avoiding the problem that the intensity of the scattered laser exceeds the upper limit of the detector 300. Moreover, through the standardized correction process, the influence of different detectors 300, optical filters 500 or experimental environments on the results is reduced, making the detection method more universal and repeatable, and meeting the quality monitoring needs in large-area production process.

[0072] It should be noted that Psample1 is the integral area of the blank carrier at the fluorescence signal wavelength interval, and Plaser1 is the integral area of the blank carrier at the laser wavelength. After Ccontrol is calculated, the integral of the Ccontrol curve at the fluorescence signal wavelength interval is obtained, i.e., Psample1; and the integral of the Ccontrol curve at the laser wavelength is obtained, i.e., Plaser1.

[0073] In one embodiment, as shown in FIG. 2, step S2 includes: Figure 1 and Figure 3 As shown in FIG. 2, step S2 includes:

[0074] The sample is placed at the mounting position 210 of the integrating sphere 200;

[0075] When the laser 100 is in an off state, the response of the sample in a dark state to the laser 100 is tested, and a dark state curve D2 of the sample is obtained.

[0076] When the laser 100 is in an on state, the sample is excited by the laser 100, and a signal curve L2 of the sample is tested. After correction, a signal curve Csample of the sample is: Csample=(L2-D2)*S*T.

[0077] The integral of the Csample curve at different wavelength intervals is calculated to obtain Psample2 and Plaser2.

[0078] By testing the dark state curve D2 of the sample in the off state of the laser 100, the interference of background noise such as ambient light and dark current of the detector 300 on the signal can be deducted. For example, before laser excitation, the system may have thermal noise or ambient light interference. The deduction of D2 can ensure that the L2 signal only contains the effective signal generated by laser excitation, and avoid measurement deviation caused by background noise.

[0079] The sample signal L2 is corrected (Csample=(L2-D2)ST) using the calibrated system spectral responsivity S and the transmittance T of the optical filter 500 in step S1. Among them, S can compensate for the response difference of the detector 300 to different wavelengths of light (such as different sensitivities of the detector 300 to ultraviolet light and infrared light), and T can correct the attenuation effect of the optical filter 500 on specific wavelengths of light, to ensure that the final signal Csample truly reflects the fluorescence emission intensity of the sample.

[0080] Furthermore, steps S2 and S1 use the same correction factors (S and T) to ensure consistent measurement benchmarks for the blank carrier and sample. For example, if there are slight variations in the optical path within integrating sphere 200 or the sensitivity of detector 300, the consistent application of S and T can offset the impact of these variations on the measurement results, avoiding calculation errors caused by system fluctuations. This consistent design makes the difference calculations (Psample2 - Psample1) and (Plaser1 - Plaser2) more reliable, thereby improving the accuracy of the fluorescence quantum yield (QY).

[0081] It should be noted that Psample2 is the integrated area of ​​the sample over the fluorescence signal wavelength range, and Plaser2 is the integrated area of ​​the sample at the laser wavelength. After calculating Csample, integrate the Csample curve over the fluorescence signal wavelength range to obtain Psample2; integrate the Csample curve at the laser wavelength to obtain Plaser2.

[0082] It should be noted that in order to ensure the accuracy of the test results, the fluorescence signal wavelength range of the blank carrier and the sample, as well as the laser wavelength, must be consistent so that systematic errors (such as background noise, spectral responsivity, etc.) can be eliminated through difference calculation.

[0083] In one embodiment, Figure 4 As shown, the integrating sphere 200 is connected to the receiving end of the detector 300 via the optical fiber 400. Positioning the optical filter 500 before the receiving end of the detector 300 includes positioning the optical filter 500 at the end of the optical fiber 400 facing away from the detector 300. Mounting the optical filter 500 at the end of the optical fiber 400 facing away from the detector 300 facilitates direct replacement of the optical filter 500 on the integrating sphere 200 side. Mounting the filter 500 at position 210 does not require disassembly of the internal structure of the detector 300; access is only required at the interface of the optical fiber 400, reducing the complexity and cost of system maintenance.

[0084] In one embodiment, Figure 5 As shown, integrating sphere 200 is connected to the receiving end of detector 300 via optical fiber 400. Placing optical filter 500 before the receiving end of detector 300 includes placing optical filter 500 between optical fiber 400 and detector 300. Connecting integrating sphere 200 and detector 300 via optical fiber 400 allows optical filter 500 to be precisely positioned in the optical signal transmission path (i.e., between optical fiber 400 and detector 300), ensuring that the optical signal incident on detector 300 is first filtered by optical filter 500. This arrangement effectively blocks scattered light at the laser wavelength (such as the strong laser scattering interference mentioned in the background technology), allowing only the fluorescence signal to pass through. This prevents saturation of detector 300 due to excessive laser intensity and significantly improves the accuracy of fluorescence quantum yield calculations.

[0085] In one embodiment, a long-pass filter is selected, wherein the long-pass filter has a wavelength greater than or equal to 600 nm and less than or equal to 700 nm. Alternatively, a wide-pass filter 500 is selected, wherein the wide-pass filter 500 has a wavelength greater than 100 nm. The long-pass filter limits the wavelength to the range of 600-700 nm, and the wide-pass filter 500 allows light greater than 100 nm to pass, both of which can effectively filter the interference light of the laser wavelength. Since the fluorescence signal wavelength generated by the perovskite film excited by the laser is usually longer than the laser wavelength, by screening through the filter 500, it can be ensured that the detector 300 only receives light in the fluorescence signal wavelength range, avoiding the entry of laser scattered light into the detector 300, thereby preventing the problem of the detector 300 being saturated and the data being distorted due to the laser intensity being too high, making the measured fluorescence signal purer, and the calculated fluorescence quantum yield more accurate.

[0086] In addition, the long-pass filter is suitable for samples with a narrow known fluorescence emission wavelength range, and can accurately filter stray light; the wide-pass filter 500 is suitable for samples with unclear or wide fluorescence emission characteristics, providing a flexible solution for fluorescence quantum yield detection in different application scenarios, and expanding the application range of the detection system.

[0087] In one embodiment, a blank carrier plate is prepared using a material with a refractive index greater than 1.5. The refractive index of the perovskite film is usually between 1.5-3.0, and the blank carrier plate with a refractive index greater than 1.5 can make its optical properties closer to the sample substrate. When the refractive indices of the blank carrier plate and the sample substrate are close, the difference between the two in terms of laser reflection and scattering behavior is smaller, and the interference of the blank carrier plate itself on the fluorescence signal (such as stray light of non-sample fluorescence) can be more accurately excluded.

[0088] In addition, high-refractive-index materials have better chemical stability and optical uniformity, which can reduce the spectral fluctuations caused by material non-uniformity of the blank carrier plate, make the repeatability of Psample1 and Plaser1 in multiple detections higher, and thus ensure the consistency of the QY calculation results. Moreover, the surface of the high-refractive-index carrier plate is smoother, which can reduce the scattering loss of the fluorescence signal on the carrier plate surface, making the integral area Psample1 of the fluorescence signal wavelength range of the blank carrier plate more stable, so that Psample2 (the real fluorescence signal of the sample) calculated by the difference in the sample detection is more reliable.

[0089] In this embodiment, the blank carrier plate is prepared using a high-refractive-index material such as spectralon, magnesium oxide, or barium sulfate.

[0090] The present application also provides a system using any of the above fluorescence quantum yield detection methods, such as Figure 4As shown in the figure, the fluorescence quantum yield detection system comprises a laser 100, an integrating sphere 200, a communication-connected detector 300 and a controller 600, and a filter 500, the controller 600 is used for receiving data information transmitted by the detector 300 and calculating the fluorescence quantum yield according to the data information; the filter 500 is arranged in the integrating sphere 200 and connected with the receiving end of the detector 300.

[0091] The fluorescence quantum yield detection system described above can selectively block the scattered light of the laser wavelength and only allow the fluorescence signal to enter the detector 300 by arranging the filter 500 in the integrating sphere 200 and connecting the filter 500 with the receiving end of the detector 300, thereby solving the problem of overloading of the detector 300 caused by the increase of the laser scattering intensity and avoiding the distortion of the measurement data caused by the laser noise interference. The fluorescence quantum yield detection system of the present application isolates the laser wavelength from the fluorescence wavelength through the filter 500, so that it is not necessary to rely on high laser intensity even in the low fluorescence quantum yield scene, thereby avoiding the situation that the detector 300 exceeds the detection upper limit due to the laser scattering and ensuring the accuracy of the fluorescence quantum yield calculation. The detector 300 transmits the fluorescence signal and the laser signal to the controller 600, the controller 600 calculates according to the corresponding signal and the fluorescence quantum yield detection method described above, and then calculates the fluorescence quantum yield of the sample. In one embodiment, as shown in the figure, Figure 4 As shown in the figure, the fluorescence quantum yield detection system further comprises an optical fiber 400, the optical fiber 400 is used for connecting the integrating sphere 200 and the receiving end of the detector 300, and the filter 500 is located at the end of the optical fiber 400 away from the detector 300. The integrating sphere 200 is connected with the detector 300 through the optical fiber 400, and the filter 500 can be arranged at the end of the optical fiber 400 away from the detector 300 or between the optical fiber 400 and the detector 300. This design not only facilitates the replacement and maintenance of the filter 500, but also can flexibly transmit the light signal through the optical fiber 400, thereby reducing the measurement error caused by the light path deviation and being suitable for the online detection scene in the production line.

[0092] In one embodiment, as shown in the figure, Figure 4 As shown in the figure, the inner circumferential surface of the integrating sphere 200 comprises a mounting position 210, the integrating sphere 200 is provided with an incident port, and the incident port and the mounting position 210 are arranged at intervals along the radial direction of the integrating sphere 200. The mounting position 210 is arranged on the inner circumferential surface of the integrating sphere 200, which facilitates the mounting of the blank carrier plate or the sample, and the incident port and the mounting position 210 are distributed at intervals along the radial direction, so that the laser can be incident on the sample at a non-straight angle, thereby avoiding the direct reflection of the laser into the detector 300. At the same time, the diffuse reflection characteristics of the inner wall of the integrating sphere 200 can uniformly collect the fluorescence excited by the sample, reduce the light signal loss, and improve the signal-to-noise ratio.

[0093] In one embodiment of the present application, as shown in the figure, Figure 4As shown, the exit port of the integrating sphere 200 is provided with a filter 500, and the exit port is perpendicular to the connecting line of the mounting position 210 and the entrance port.

[0094] In one embodiment, the filter 500 includes a long-pass filter, and the wavelength of the long-pass filter is greater than or equal to 600 nm and less than or equal to 700 nm. The fluorescence emission wavelength of the perovskite material is usually longer than the laser excitation wavelength due to the Stokes shift (for example, when the common 532 nm laser excitation, the fluorescence wavelength is usually in the range of 600-700 nm). The long-pass filter (600-700 nm) can selectively block the scattered light of the laser wavelength (such as 532 nm) and only allow the fluorescence signal to pass through, thereby avoiding the saturation problem of the detector 300 caused by the enhancement of the laser intensity and ensuring the accuracy of the integral data of Psample1 / Psample2.

[0095] In addition, the narrow-band characteristic of the long-pass filter can reduce the interference of non-fluorescent signals such as ambient light and stray light. For example, when the laser wavelength is 532 nm, the long-pass filter above 600 nm can accurately limit the wavelength range of the fluorescence signal, so that the integral calculation of the Ccontrol curve and the Csample curve is only for the target fluorescence spectrum, thereby improving the reliability of the fluorescence quantum yield (QY) calculation.

[0096] In addition, the photoluminescence spectrum peak of the perovskite thin film is usually in the range of 600-700 nm, and the long-pass filter in this wavelength range can be accurately matched with the fluorescence emission characteristics of the material, maximize the collection of effective fluorescence signals during detection, reduce signal loss, and is especially suitable for high-precision detection of low-fluorescence quantum yield samples.

[0097] In one embodiment, the filter 500 includes a wide-pass filter 500, and the wavelength of the wide-pass filter 500 is greater than 100 nm. The passband range of the wide-pass filter 500 (wavelength > 100 nm) covers the ultraviolet to near-infrared band, which can adapt to the fluorescence emission characteristics of different perovskite materials or interface layer materials. For example, when the sample fluorescence wavelength range is wide (such as 500-800 nm), the wide-pass filter 500 can avoid the missed detection of fluorescence signals caused by the wavelength limitation of the long-pass filter, and improve the compatibility of the method for multi-element samples.

[0098] In addition, during the preparation of the perovskite thin film, the fluorescence characteristics of different film layers (such as precursor layers, interface modification layers) may be different. The wide-pass filter 500 can be used for rapid detection of multi-stage film layers on a continuous production line without frequent replacement of the filter 500 type, thereby reducing the detection cost and improving the production line monitoring efficiency.

[0099] In addition, the wide-pass filter 500 can cover a wide wavelength range while still blocking laser scattering light through the "separation of laser wavelength and fluorescence wavelength" mechanism (such as the above-mentioned Stokes shift). For example, when the laser wavelength is 405 nm, the wide-pass filter 500 (> 100 nm) can achieve selective collection of fluorescence signals by setting the integration interval (such as > 450 nm), which not only ensures signal strength but also avoids laser interference, and is particularly suitable for samples with broadened or shifted fluorescence spectrum.

[0100] In summary, by limiting the wavelength characteristics of the filter 500, the present application solves the problems of laser scattering interference and insufficient detection adaptability in the prior art from two dimensions of "precise matching of typical fluorescence spectrum" and "widening of detection wavelength range". The long-pass filter improves detection accuracy through narrow-band pass characteristics, and the wide-pass filter 500 enhances application flexibility through wide-band pass characteristics. Both can cooperate with the integrating sphere 200 and the correction algorithm to ultimately achieve accurate detection of low-fluorescence quantum yield samples.

[0101] The technical features of the above embodiments can be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described, but as long as the combinations of the technical features do not exist contradictory, they should be considered as the scope of the present application.

[0102] The above embodiments only express several implementation manners of the present application, and the description is more specific and detailed, but it should not be understood as a limitation on the scope of the patent application. It should be noted that for ordinary skilled persons in the art, without departing from the concept of the present application, a number of modifications and improvements can be made, which are all within the scope of the present application. Therefore, the scope of the patent of the present application should be subject to the appended claims.

Claims

1. A method for detecting fluorescence quantum yield, characterized in that: The detection method of the fluorescence quantum yield comprises: S1, placing a blank carrier plate at the installation position (210) of the integrating sphere (200), placing the filter (500) before the receiving end of the detector (300), and calculating the integral area Psample1 of the blank carrier plate in the fluorescence signal wavelength range and the integral area Plaser1 of the blank carrier plate at the laser wavelength; S2, placing a sample at the installation position (210) of the integrating sphere (200), and calculating the integrated area Psample2 of the sample in the fluorescence signal wavelength range, and the integrated area Plaser2 of the sample at the laser wavelength; S3. Substitute the above calculation results into the fluorescence quantum yield calculation formula: QY= (Psample2-Psample1) / (Plaser1-Plaser2).

2. The method for detecting fluorescence quantum yield according to claim 1, wherein Step S1 includes: Placing the blank carrier at the installation position (210), measuring an actual spectrum curve C2, comparing the factory spectrum response curve C1 of the detector (300) with the actual spectrum curve C2, and obtaining the spectral responsivity S of the test system, where S=C1 / C2; The filter (500) is arranged before the receiving end of the detector (300), a filtered spectrum curve C3 is measured, and the filtered spectrum curve C3 is compared with the actual spectrum curve C2 to obtain the spectral transmittance T of the filter (500), where T=C3 / C2; When the laser (100) is in an off state, testing the response of the blank carrier to the laser (100) in a dark state to obtain a dark state curve D1 of the blank carrier; When the laser (100) is in an on state, the blank carrier is excited by the laser (100), and a signal curve L1 of the blank carrier is tested. After correction, the signal curve of the blank carrier is Ccontrol, where Ccontrol=(L1-D1)*S*T; The integral calculation of the Ccontrol curve in different wavelength ranges is used to obtain Psample1 and Plaser1.

3. The method for detecting fluorescence quantum yield according to claim 2, wherein Step S2 includes: placing the sample at the installation position (210) of the integrating sphere (200); When the laser (100) is in an off state, testing the response of the sample to the laser (100) in a dark state to obtain a dark state curve D2 of the sample; When the laser (100) is in an on state, the sample is excited by the laser (100), and a signal curve of the sample is tested to be L2. After correction, the signal curve Csample of the sample is: Csample=(L2-D2)*S*T; The integral calculation of the Csample curve in different wavelength ranges is used to obtain Psample2 and Plaser2.

4. The method for detecting fluorescence quantum yield according to claim 2, wherein The integrating sphere (200) is connected to the receiving end of the detector (300) via an optical fiber (400), and the process of arranging the filter (500) before the receiving end of the detector (300) includes: The filter (500) is arranged at the end of the optical fiber (400) facing away from the detector (300); or, The optical filter (500) is arranged between the optical fiber (400) and the detector (300).

5. The method for detecting fluorescence quantum yield according to claim 2, wherein The optical filter (500) is a long-pass filter, wherein the wavelength of the long-pass filter is greater than or equal to 600 nm and less than or equal to 700 nm; or The optical filter (500) is a wide-pass filter, wherein the wavelength of the wide-pass filter is greater than 100 nm.

6. The method for detecting fluorescence quantum yield according to claim 1, wherein The blank carrier is prepared by using a material with a refractive index greater than 1.

5.

7. A system using the fluorescence quantum yield detection method according to any one of claims 1 to 6, characterized in that: The fluorescence quantum yield detection system comprises: Laser (100); Integrating sphere (200); A detector (300) and a controller (600) are communicatively connected, wherein the controller (600) is used to receive data information transmitted by the detector (300) and calculate the fluorescence quantum yield based on the data information; The filter (500) is disposed in the integrating sphere (200) and connected to the receiving end of the detector (300).

8. The fluorescence quantum yield detection system according to claim 7, characterized in that: The optical filter (500) comprises a long-pass filter, wherein the wavelength of the long-pass filter is greater than or equal to 600 nm and less than or equal to 700 nm.

9. The fluorescence quantum yield detection system according to claim 7, characterized in that: The optical filter (500) comprises a wide-pass filter, wherein the wavelength of the wide-pass filter is greater than 100 nm.

10. The fluorescence quantum yield detection system according to claim 7, characterized in that: The inner circumference of the integrating sphere (200) includes a mounting position (210), an incident port is provided on the integrating sphere (200), and the incident port and the mounting position (210) are spaced apart along the radial direction of the integrating sphere (200).

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