A blue light photodiode and a method for preparing the same

Abstract

The blue light-emitting photodiode provided by the present application and its preparation method sequentially dispose a hole transport layer, a quantum dot light-emitting layer, and an electron transport layer on a processed substrate. The hole transport layer is a I-III-VI group pyrite quantum dot. Then, a metal electrode is disposed on the anode region of the device obtained in the above step. The blue light-emitting photodiode provided by the present application uses an I-III-VI group pyrite inorganic quantum dot material to replace the traditional organic hole functional layer PEDOT:PSS / PVK, so as to achieve the purpose of energy band matching between the hole functional layer and the light-emitting layer and improve the hole mobility, making the injection balance of electrons and holes in the device and realizing an efficient and stable blue light QLED device.

Description

Technical Field

[0001] This application relates to the technical field of photodiodes, and particularly to a blue photodiode and a preparation method thereof. Background Art

[0002] A light-emitting diode is a commonly used light-emitting device that emits light by the recombination of electrons and holes, and has currently been widely applied to displays and lighting. In the display field, quantum dot light-emitting diodes (QLEDs) have advantages over organic light-emitting diodes (OLEDs) in many aspects. First, quantum dots have a size confinement effect. By controlling the shape, structure, and size of quantum dots, the width of their energy gap can be adjusted, thereby changing their electrical and optical properties. Second, most of the light-emitting materials used in QLEDs are inorganic quantum dot crystals, with more stable material properties, longer lifespan, and lower cost; due to the relatively narrow emission spectrum of quantum dots, QLEDs have a wider color gamut and more perfect color performance; in addition, the QLED display process is more compatible with flexible and lightweight plastic substrates. These advantages make the QLED display technology have broad research prospects.

[0003] The main existing problem is that the luminous efficiency and lifespan of blue QLEDs have not yet reached the level of red and green QLEDs. There are two main factors affecting the device performance: 1) the injection barrier between the hole transport layer and the quantum dot active layer. 2) The hole mobility. These two factors result in the hole injection and transport efficiency being lower than that of electrons, reducing the recombination of electrons and holes in the active layer. Summary of the Invention

[0004] In view of this, it is necessary to provide a blue photodiode that achieves high efficiency and stability in view of the defects of high hole injection barrier and low mobility in the prior art.

[0005] To solve the above problems, this application adopts the following technical solutions:

[0006] On the one hand, this application provides a blue photodiode, including a substrate, a hole transport layer, a quantum dot light-emitting layer, an electron transport layer, and an electrode sequentially arranged from bottom to top, wherein the hole transport layer is a I-III-VI group pyrite quantum dot.

[0007] In some embodiments, the substrate includes indium tin oxide conductive glass.

[0008] In some embodiments, the indium tin oxide conductive glass has a size of 15mm * 15mm, a thickness of 1 - 2mm, and a visible light transmittance of about 70% - 90%.

[0009] In some of these embodiments, the I-III-VI group pyrite quantum dots include one of copper indium sulfide quantum dots, copper gallium sulfide quantum dots, copper indium gallium sulfide quantum dots, silver copper indium sulfide quantum dots, silver copper gallium sulfide quantum dots, or silver copper indium gallium sulfide quantum dots.

[0010] In some of these embodiments, the quantum dot light-emitting layer is a cadmium-based core-shell quantum dot.

[0011] In some of these embodiments, the cadmium-based core-shell quantum dot is a CdS / CdSe core-shell quantum dot, a perovskite quantum dot, a III-V group quantum dot, or other ternary or quaternary light-emitting quantum dot materials.

[0012] In some of these embodiments, the electron transport layer is a nanocrystal of ZnO.

[0013] In some of these embodiments, the electrode is silver or gold.

[0014] In some of these embodiments, the thickness of the substrate is 50 - 500 nm, the thickness of the hole transport layer is 30 - 50 nm, the thickness of the quantum dot light-emitting layer is 30 - 50 nm, the thickness of the electron transport layer is 20 - 50 nm, and the thickness of the cathode is 80 - 150 nm.

[0015] In some of these embodiments, the spatial scale of the I-III-VI group pyrite quantum dot material is 5 - 20 nm, and the average center spacing is 1 - 100 nm; the spatial scale of the quantum dot light-emitting layer is 1 - 10 nm, and the average center spacing is 1 - 100 nm; the spatial scale of the electron transport layer is 1 - 10 nm, and the average center spacing is 1 - 100 nm.

[0016] On the other hand, the present application also provides a method for manufacturing the blue light photodiode described above, including the following steps:

[0017] Treat the substrate;

[0018] Sequentially dispose a hole transport layer, a quantum dot light-emitting layer, and an electron transport layer on the treated substrate, where the hole transport layer is an I-III-VI group pyrite quantum dot;

[0019] Dispose a metal electrode on the anode region of the device obtained in the above step to obtain the blue light photodiode.

[0020] In some of these embodiments, in the step of treating the substrate, specifically:

[0021] Ultrasonically clean the substrate with detergent, deionized water, ethanol, acetone, and isopropyl alcohol, then wash and dry it, and then clean the surface with oxygen plasma.

[0022] In some of these embodiments, in the step of sequentially disposing a hole transport layer, a quantum dot light-emitting layer, and an electron transport layer on the processed substrate, specifically: spin-coating the hole transport layer, the quantum dot light-emitting layer, and the electron transport layer on the processed substrate in sequence.

[0023] In some of these embodiments, the I-III-VI group pyrite quantum dots include one of copper indium sulfide quantum dots, copper gallium sulfide quantum dots, copper indium gallium sulfide quantum dots, silver copper indium sulfide quantum dots, silver copper gallium sulfide quantum dots, or silver copper indium gallium sulfide quantum dots.

[0024] In some of these embodiments, the preparation method of the copper gallium sulfide quantum dots is as follows:

[0025] Under an anaerobic state, heating sulfur and octadecene to react at 170 - 210 °C to obtain an S precursor solution;

[0026] Under an anaerobic state, stirring and heating cuprous iodide, gallium triiodide, oleylamine, and dodecanethiol to 100 - 120 °C, and after maintaining the temperature for 15 - 25 min, heating to 170 - 190 °C to obtain a pre-reaction solution;

[0027] Mixing and reacting the S precursor solution and the pre-reaction solution, and then naturally cooling to room temperature to obtain a mother liquor;

[0028] Dispersing the mother liquor with excessive n-hexane, centrifuging to remove the precipitate, and then precipitating the filtrate with excessive ethanol to obtain a solid sample;

[0029] Purifying the solid sample and finally dispersing it in n-hexane to obtain the copper gallium sulfide quantum dots.

[0030] The blue light photodiode and its preparation method provided by this application sequentially dispose a hole transport layer, a quantum dot light-emitting layer, and an electron transport layer on the processed substrate. The hole transport layer is an I-III-VI group pyrite quantum dot, and then a metal electrode is disposed on the anode region of the device obtained in the above steps. The blue light photodiode provided by this application uses an I-III-VI group pyrite inorganic quantum dot material to replace the traditional organic hole functional layer PEDOT:PSS / PVK to achieve the purpose of energy band matching between the hole functional layer and the light-emitting layer and improving the hole mobility, so that the injection of electrons and holes in the device is balanced, and an efficient and stable blue light QLED device is realized. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] In order to more clearly illustrate the technical solutions of the embodiments of this application, the following will briefly introduce the drawings required to be used in the embodiments of this application or the description of the prior art. Obviously, the following described drawings are only some embodiments of this application. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0032] Figure 1 Schematic structural diagram of the blue - light photodiode provided for this application;

[0033] Figure 2 Flow chart of the steps for preparing the blue - light photodiode provided for this application;

[0034] Figure 3 Schematic flow diagram of the preparation method of CuGaS2 quantum dots in Example 1 of this application. Detailed implementation manners

[0035] The following details the embodiments of this application. The examples of the embodiments are shown in the drawings, where the same or similar reference numerals represent the same or similar elements or elements with the same or similar functions throughout. The embodiments described below with reference to the drawings are exemplary and are intended to explain this application and should not be construed as limiting this application.

[0036] In the description of this application, it should be understood that the orientation or positional relationships indicated by terms such as "upper", "lower", "horizontal", "inner", "outer", etc. are based on the orientation or positional relationships shown in the drawings, and are only for the convenience of describing this application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as limiting this application.

[0037] In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, features defined with "first" and "second" may explicitly or implicitly include one or more of such features. In the description of this application, "a plurality" means two or more unless otherwise specifically defined.

[0038] In order to make the purpose, technical solutions and advantages of this application more clear, the following further details this application in combination with the drawings and embodiments.

[0039] Please refer to Figure 1 , which is a schematic structural diagram of the blue - light photodiode provided for the embodiments of this application, including a substrate 110, a hole - transporting layer 120, a quantum - dot light - emitting layer 130, an electron - transporting layer 140, and an electrode 150 arranged in sequence from bottom to top. The hole - transporting layer 120 is a I - III - VI group pyrite quantum dot. The following details the specific structures of each layer.

[0040] In some of the embodiments, the substrate 110 includes indium tin oxide conductive glass 111.

[0041] Specifically, the substrate 110 is a surface-treated indium tin oxide conductive glass (ITO glass).

[0042] In some embodiments, the indium tin oxide conductive glass has a size of 15 mm * 15 mm, a thickness of 1 - 2 mm, and a visible light transmittance of about 80%.

[0043] In some embodiments, the I-III-VI group pyrite quantum dots include one of copper indium sulfide quantum dots, copper gallium sulfide quantum dots, copper indium gallium sulfide quantum dots, silver copper indium sulfide quantum dots, silver copper gallium sulfide quantum dots, or silver copper indium gallium sulfide quantum dots.

[0044] It can be understood that as a typical inorganic p-type compound semiconductor material, pyrite compounds have high hole mobility, strong stability, and adjustable band gaps, and are suitable as materials for the hole transport layer.

[0045] It can be understood that the valence band energy level of copper gallium sulfide (CuGaS2) quantum dots is lower, reducing the potential barrier between the hole transport layer and the light-emitting layer; and CuGaS2 quantum dots are inorganic materials, which are more stable and have a longer working life compared to organic materials. In some embodiments, the quantum dot light-emitting layer 130 is a cadmium-based core-shell quantum dot.

[0046] Furthermore, the cadmium-based core-shell quantum dots are CdS / CdSe core-shell quantum dots, perovskite quantum dots, III-V group quantum dots, or other ternary or quaternary light-emitting quantum dot materials.

[0047] In some embodiments, oleylamine and oleic acid ligands are also attached to the surface of the cadmium-based core-shell quantum dots.

[0048] In some embodiments, the electron transport layer 140 is a nanocrystal of ZnO.

[0049] It can be understood that the hole mobility of the CuGaS2 quantum dot material is similar to the electron mobility of the electron transport layer ZnO, and carrier injection is more balanced.

[0050] In some embodiments, the electrode 150 is silver or gold.

[0051] In some embodiments, the thickness of the substrate is 50 - 500 nm, the thickness of the hole transport layer is 30 - 50 nm, the thickness of the quantum dot light-emitting layer is 30 - 50 nm, the thickness of the electron transport layer is 20 - 50 nm, and the thickness of the cathode is 80 - 150 nm.

[0052] In some of these embodiments, the spatial scale of the I-III-VI group pyrite quantum dot material is 5-20 nm, and the average center spacing is 1-100 nm; the spatial scale of the quantum dot light-emitting layer is 1-10 nm, and the average center spacing is 1-100 nm; the spatial scale of the electron transport layer is 1-10 nm, and the average center spacing is 1-100 nm.

[0053] The blue light photodiode provided by the embodiments of the present application uses an I-III-VI group pyrite inorganic quantum dot material to replace the traditional organic hole functional layer PEDOT:PSS / PVK, so as to achieve the energy band matching between the hole functional layer and the light-emitting layer and improve the hole mobility, so that the injection of electrons and holes in the device is balanced, and an efficient and stable blue light QLED device is realized.

[0054] Please refer to Figure 2 , which is the preparation method of the blue light photodiode provided by the present application, and includes the following steps:

[0055] Step S110: Treat the substrate.

[0056] Specifically, the substrate is ultrasonically cleaned with detergent, deionized water, ethanol, acetone and isopropanol respectively, then washed, dried, and the surface is cleaned by oxygen plasma.

[0057] Step S120: Sequentially arrange a hole transport layer, a quantum dot light-emitting layer and an electron transport layer on the treated substrate, and the hole transport layer is an I-III-VI group pyrite quantum dot.

[0058] Specifically, the hole transport layer, the quantum dot light-emitting layer and the electron transport layer are sequentially spin-coated on the treated substrate.

[0059] Step S130: Set a metal electrode on the anode region of the device obtained in the above steps to obtain the blue light photodiode.

[0060] In some of these embodiments, in the step of treating the substrate, specifically:

[0061] The substrate is ultrasonically cleaned with detergent, deionized water, ethanol, acetone and isopropanol respectively, then washed, dried, and the surface is cleaned by oxygen plasma.

[0062] In some of these embodiments, in the step of sequentially arranging a hole transport layer, a quantum dot light-emitting layer and an electron transport layer on the treated substrate, specifically: the hole transport layer, the quantum dot light-emitting layer and the electron transport layer are sequentially spin-coated on the treated substrate.

[0063] In some of these embodiments, the I-III-VI group pyrite quantum dots include one of copper indium sulfide quantum dots, copper gallium sulfide quantum dots, copper indium gallium sulfide quantum dots, silver copper indium sulfide quantum dots, silver copper gallium sulfide quantum dots, and silver copper indium gallium sulfide quantum dots.

[0064] In some of these embodiments, the I-III-VI group pyrite quantum dots include one of copper indium sulfide quantum dots, copper gallium sulfide quantum dots, copper indium gallium sulfide quantum dots, silver copper indium sulfide quantum dots, silver copper gallium sulfide quantum dots, and silver copper indium gallium sulfide quantum dots.

[0065] It can be understood that as a typical inorganic p-type compound semiconductor material, the pyrite compound has a high hole mobility, strong stability, and an adjustable bandgap, making it suitable as a material for the hole transport layer. In some of these embodiments, the preparation method of the copper gallium sulfide quantum dots is as follows:

[0066] Step S210: Under an anaerobic state, heat sulfur and octadecene to react at 170-210 °C to obtain an S precursor solution;

[0067] Step S220: Under an anaerobic state, stir and heat cuprous iodide, gallium triiodide, oleylamine, and dodecanethiol to 100-120 °C, keep warm for 15-25 min, and then heat to 170-190 °C to obtain a pre-reaction solution;

[0068] Step S230: Mix and react the S precursor solution and the pre-reaction solution, and then naturally cool to room temperature to obtain a mother liquor;

[0069] Step S240: Disperse the mother liquor with excessive n-hexane, centrifuge to remove the precipitate, and then precipitate the filtrate with excessive ethanol to obtain a solid sample;

[0070] Step S250: Purify the solid sample and finally disperse it in n-hexane to obtain the copper gallium sulfide quantum dots.

[0071] It can be understood that the valence band energy level of copper gallium sulfide (CuGaS2) quantum dots is lower, reducing the potential barrier between the hole transport layer and the light-emitting layer; and the CuGaS2 quantum dots are inorganic materials, which are more stable in nature and have a longer working life compared to organic materials.

[0072] The blue light photodiode prepared in the above embodiments of the present application uses an I-III-VI group pyrite inorganic quantum dot material to replace the traditional organic hole functional layer PEDOT:PSS / PVK, so as to achieve the purpose of energy band matching between the hole functional layer and the light-emitting layer and improve the hole mobility, making the injection of electrons and holes in the device balanced, and realizing an efficient and stable blue light QLED device.

[0073] The above technical solutions of the present application will be described in detail below in conjunction with specific embodiments.

[0074] Example 1

[0075] Please refer to Figure 3 , Figure 3 which shows a schematic flow chart of the preparation method of CuGaS2 quantum dots in an embodiment of the present invention. The specific technical solution is as follows:

[0076] Step 1: After washing all the involved glass instruments and related accessories such as three-necked flasks, glass stopcocks, polytetrafluoroethylene stirrers, etc., they need to be placed in an oven and dried at 60°C for 30 minutes.

[0077] Step 2: Weigh sulfur powder (1 mmol, 64.0 mg) and octadecene (3 ml) and put them into a dry three-necked flask.

[0078] Step 3: Place the flask on a magnetic stirring heater, fix the flask with an iron stand, seal the bottle mouth with two stopcocks coated with silicone grease and a rubber stopper. Insert a 1 mm thermocouple through the rubber stopper to measure the temperature of the liquid, and the insertion position should be two-thirds below the liquid level. Connect one stopcock to a double manifold, and the other end to an oil bubbler for liquid sealing. Evacuate the reaction system with the double manifold for 30 s, then fill it with N2 for 30 s, and repeat three times to maintain an anaerobic environment. After the operation is completed, start heating and stirring, and dry at 190°C under a N2 atmosphere for 30 min to obtain the S precursor solution.

[0079] Step 4: Weigh cuprous iodide (0.25 mmol, 47.6 mg), gallium triiodide (0.25 mmol, 112.6 mg), oleylamine (3 ml), and n-dodecanethiol (0.3 ml) into another dry three-necked flask.

[0080] Step 5: Place the flask on a magnetic stirring heater, fix the flask with an iron stand, seal the bottle mouth with two stopcocks coated with silicone grease and a rubber stopper. Insert a 1 mm thermocouple through the rubber stopper to measure the temperature of the liquid, and the insertion position should be two-thirds below the liquid level. Connect one stopcock to a double manifold, and the other end to an oil bubbler for liquid sealing. Evacuate the reaction system with the double manifold for 30 s, then fill it with N2 for 30 s, and repeat three times. After the operation is completed, start heating and stirring, dry at 120°C under a N2 atmosphere for 20 min, and then raise the temperature to 180°C to obtain the pre-reaction solution and prepare for the reaction.

[0081] Step 6: Use a glass syringe to draw 1.5 ml of the S precursor solution while it is hot and inject it into the pre-reaction solution. After maintaining for 5 min, end the reaction and let it cool naturally to room temperature.

[0082] Step 7: Take the mother liquor after the reaction, disperse it with an excessive amount of n-hexane, centrifuge to remove the precipitate, precipitate the solution with an excessive amount of ethanol to obtain a solid sample, purify the sample by the method of dissolution-reprecipitation, and finally disperse it in n-hexane to obtain CuGaS2 quantum dots with a concentration of about 30 mg / ml.

[0083] In the above embodiments of the present application, the valence band energy level of the prepared copper gallium sulfide (CuGaS2) quantum dots is lower, reducing the potential barrier between the hole transport layer and the light-emitting layer; and the CuGaS2 quantum dots are inorganic materials, which are more stable in nature and have a longer working life compared to organic materials.

[0084] Example 2

[0085] The present embodiment provides a preparation method for a blue light quantum dot light-emitting diode structure, and the specific technical solution is as follows:

[0086] Step 1: Ultrasonically clean the ITO conductive glass with detergent, deionized water, ethanol, acetone, and isopropanol for 20 minutes respectively.

[0087] Step 2: After the ITO conductive glass is washed and dried, surface treat it with an oxygen plasma cleaner for 10 minutes to increase its surface wettability.

[0088] Step 3: Transfer the ITO glass to a glove box with a nitrogen atmosphere, and sequentially spin-coat the CuGaS2 quantum dot solution, CdS / CdSe core-shell quantum dot solution, and ZnO nanocrystal solution on the ITO glass, and anneal at 60 °C for 30 minutes.

[0089] Step 4: Scrape off the sample in the anode region of the device to expose the ITO layer, and finally evaporate a 100-nm metal silver electrode on it to obtain a blue light photodiode.

[0090] It should be noted that the concentration of the Cu-Ga-S quantum dot solution is about 30 mg / ml, and the spin-coating parameters are 2000 rpm and 30 s. The concentration of the CdS / CdSe core-shell quantum dot solution is about 25 mg / ml, and the spin-coating parameters are 2000 rpm and 30 s. The concentration of the ZnO nanocrystal solution is about 25 mg / ml, and the spin-coating parameters are 1500 rpm and 60 s.

[0091] The blue light photodiode prepared in the above embodiments of the present application uses a group I-III-VI pyrite inorganic quantum dot material to replace the traditional organic hole functional layer PEDOT:PSS / PVK, so as to achieve the energy band matching between the hole functional layer and the light-emitting layer and improve the hole mobility, making the injection of electrons and holes in the device balanced and realizing an efficient and stable blue light QLED device.

[0092] The above are only preferred embodiments of the present application, and only specifically describe the technical principles of the present application. These descriptions are only for explaining the principles of the present application and cannot be interpreted as limiting the scope of protection of the present application in any way. Based on the explanation here, any modifications, equivalent substitutions and improvements made within the spirit and principles of the present application, and other specific implementation methods of the present application that can be associated with the technicians in this field without creative work, should be included in the scope of protection of the present application.

Claims

1. A blue light photodiode, characterized in that, It includes a substrate, a hole transport layer, a quantum dot light-emitting layer, an electron transport layer, and an electrode which are sequentially arranged from bottom to top. The hole transport layer is a pyrite quantum dot of I-III-VI group; The pyrite quantum dot of I-III-VI group is a copper gallium sulfide quantum dot; The quantum dot light-emitting layer is a cadmium-based core-shell quantum dot; The cadmium-based core-shell quantum dot is a CdS / CdSe core-shell quantum dot; The electron transport layer is a nanocrystal of ZnO; The electrode is silver or gold; The preparation method of the blue light photodiode includes the following steps: Treat the substrate; Sequentially set a hole transport layer, a quantum dot light-emitting layer, and an electron transport layer on the treated substrate. The hole transport layer is a pyrite quantum dot of I-III-VI group; Set a metal electrode on the anode region of the device obtained in the above step to obtain the blue light photodiode; In the step of sequentially setting a hole transport layer, a quantum dot light-emitting layer, and an electron transport layer on the treated substrate, specifically: spin-coat a CuGaS2 quantum dot solution, a CdS / CdSe core-shell quantum dot solution, and a nanocrystal solution of ZnO on the treated substrate in sequence; The preparation method of the copper gallium sulfide quantum dot is as follows: Under an anaerobic state, heat sulfur and octadecene to 170-210 °C for reaction to obtain an S precursor solution; Under an anaerobic state, stir and heat cuprous iodide, gallium triiodide, oleylamine, and dodecanethiol to 100-120 °C, keep warm for 15-25 min, and then heat to 170-190 °C to obtain a pre-reaction solution; Mix and react the S precursor solution and the pre-reaction solution, and then naturally cool to room temperature to obtain a mother liquor; Disperse the mother liquor with excessive n-hexane, centrifuge to remove the precipitate, and then precipitate the filtrate with excessive ethanol to obtain a solid sample; Purify the solid sample and finally disperse it in n-hexane to obtain the copper gallium sulfide quantum dot.

2. The blue light photodiode according to claim 1, wherein The substrate includes indium tin oxide conductive glass.

3. The blue light photodiode according to claim 2, wherein The size of the indium tin oxide conductive glass is 15 mm * 15 mm, the thickness is 1-2 mm, and the visible light transmittance is 70%-80%.

4. The blue light photodiode according to claim 1, characterized in that, The thickness of the substrate is 50-500 nm, the thickness of the hole transport layer is 30-50 nm, the thickness of the quantum dot light-emitting layer is 30-50 nm, and the thickness of the electron transport layer is 20-50 nm.

5. The blue light photodiode according to claim 1, characterized in that, The spatial scale of the pyrite quantum dot material of I-III-VI group is 5-20 nm, and the central average spacing is 1-100 nm; the spatial scale of the quantum dot light-emitting layer is 1-10 nm, and the central average spacing is 1-100 nm; the spatial scale of the electron transport layer is 1-10 nm, and the central average spacing is 1-100 nm.

6. A method for preparing a blue light photodiode according to any one of claims 1 to 5, characterized in that, It includes the following steps: Treat the substrate; Sequentially set a hole transport layer, a quantum dot light-emitting layer, and an electron transport layer on the treated substrate. The hole transport layer is a pyrite quantum dot of I-III-VI group; Set a metal electrode on the anode region of the device obtained in the above step to obtain the blue light photodiode; In the step of sequentially disposing a hole transport layer, a quantum dot light-emitting layer, and an electron transport layer on the processed substrate, specifically: sequentially spin-coating a CuGaS2 quantum dot solution, a CdS / CdSe core-shell quantum dot solution, and a nanocrystal solution of ZnO on the processed substrate; The preparation method of the copper gallium sulfide quantum dots is as follows: Under an anaerobic state, heating sulfur and octadecene to react at 170 - 210 °C to obtain an S precursor solution; Under an anaerobic state, stirring and heating cuprous iodide, gallium triiodide, oleylamine, and dodecanethiol to 100 - 120 °C, holding for 15 - 25 min, and then heating to 170 - 190 °C to obtain a pre-reaction solution; Mixing and reacting the S precursor solution and the pre-reaction solution, and then naturally cooling to room temperature to obtain a mother liquor; Dispersing the mother liquor with an excessive amount of n-hexane, centrifuging to remove the precipitate, and then precipitating the filtrate with an excessive amount of ethanol to obtain a solid sample; Purifying the solid sample and finally dispersing it in n-hexane to obtain the copper gallium sulfide quantum dots.

7. The manufacturing method of the blue light photodiode according to claim 6, characterized in that, In the step of processing the substrate, specifically: Ultrasonically cleaning the substrate with a detergent, deionized water, ethanol, acetone, and isopropanol respectively, rinsing and drying, and then cleaning the surface with oxygen plasma.

8. The manufacturing method of the blue light photodiode according to claim 6, characterized in that, The preparation method of the copper gallium sulfide quantum dots is as follows: Under an anaerobic state, heating sulfur and octadecene to react at 170 - 210 °C to obtain an S precursor solution; Under an anaerobic state, stirring and heating cuprous iodide, gallium triiodide, oleylamine, and dodecanethiol to 100 - 120 °C, holding for 15 - 25 min, and then heating to 170 - 190 °C to obtain a pre-reaction solution; Mixing and reacting the S precursor solution and the pre-reaction solution, and then naturally cooling to room temperature to obtain a mother liquor; Dispersing the mother liquor with an excessive amount of n-hexane, centrifuging to remove the precipitate, and then precipitating the filtrate with an excessive amount of ethanol to obtain a solid sample; Purifying the solid sample and finally dispersing it in n-hexane to obtain the copper gallium sulfide quantum dots.

Images