Synthesis method of narrow-band-gap metal telluride semiconductor material

Abstract

The invention relates to a synthesis method of a narrow-band-gap metal telluride semiconductor material, and belongs to the technical field of semiconductor materials, and the synthesis method comprises the following steps: S1, preparing a Te precursor solution A; s2, preparing a metal precursor solution B; s3, heating the metal precursor solution B, extracting the Te precursor solution A, and injecting the Te precursor solution A into the metal precursor solution B to obtain a narrow-band-gap metal telluride colloidal quantum dot crude product dispersion liquid; s4, precipitating and purifying the narrow-band-gap metal telluride colloidal quantum dot crude dispersion liquid to obtain a narrow-band-gap metal telluride colloidal quantum dot fine dispersion liquid; the preparation method has the beneficial effects that the size and morphology of the metal telluride colloidal quantum dots are regulated and controlled, and the particle size is regulated by introducing thiol ligands with different chain lengths.

Description

Technical Field

[0001] This invention belongs to the field of semiconductor materials and relates to the synthesis technology of narrow bandgap metal telluride colloidal quantum dots, specifically to a method for synthesizing narrow bandgap metal telluride semiconductor materials. Background Technology

[0002] Infrared photodetectors, as a core sensing technology, are experiencing an unprecedented surge in applications. Their use has rapidly expanded from traditional military security and industrial inspection to drone logistics, air traffic management, and autonomous driving. Currently, commercial detectors primarily rely on epitaxially grown InGaAs and HgCdTe materials, but their high manufacturing costs and complex flip-chip bonding processes limit the widespread adoption of infrared technology in civilian applications. Compared to traditional single-crystal inorganic semiconductors, colloidal quantum dots, due to their tunable bandgap, low synthesis cost, excellent solution processability, and direct integration with CMOS readout circuits (ROIC), have become a viable alternative material for next-generation infrared detectors.

[0003] Precise control of key parameters such as the size, shape, and crystal structure of quantum dots is fundamental to achieving their superior performance during integration. However, current narrow-bandgap metal telluride colloidal quantum dot materials still face many challenges in synthesis, such as poor precursor stability, low synthesis controllability, and Pb... 2+ Hg 2+ isocations and Te 2- The mismatch in reaction rates can easily lead to non-uniform nucleation and the formation of polydisperse quantum dots. To avoid this problem, the more reactive (TMS)₂Te is used as a tellurium precursor, but its high cost and strong toxicity limit its industrial application and make it difficult to meet the demand. Furthermore, the synthesis of PbTe and SnTe often relies on high-temperature reactions; however, the high-temperature environment makes precise control of the reaction rate extremely difficult, which not only increases the uncertainty of the synthesis process but may also lead to inconsistent product quality, failing to meet the needs of practical applications. Therefore, developing new synthesis techniques to improve the performance and scalability of narrow-bandgap metal telluride colloidal quantum dot materials has become a critical issue that urgently needs to be addressed in this field.

[0004] However, the shortcomings of existing technologies can be summarized in the following three points:

[0005] 1. HgTe colloidal quantum dots prepared by existing synthesis methods are mostly tetrapod-shaped. During the later ligand exchange, the tetrapods are prone to breakage. After breakage, the size and shape of the quantum dots become more irregular, resulting in poor monodispersity of the material, which in turn affects the stability and consistency of its optical and electrical properties.

[0006] 2. Current methods for synthesizing HgTe and PbTe colloidal quantum dots control the size through temperature. While this allows for control over the quantum dot size, at lower temperatures, Pb... 2+ Hg 2+ Cations and Te 2- The mismatch in reaction rates becomes increasingly significant, leading to defects or impurities on the surface of quantum dots, which affect their optical and electrical properties.

[0007] 3. Existing synthetic methods for preparing PbTe and SnTe often rely on high-temperature reactions. However, the high-temperature environment makes it extremely difficult to precisely control the reaction rate, which not only increases the uncertainty of the synthesis process but may also lead to inconsistent product quality, making it difficult to meet the needs of practical applications. Summary of the Invention

[0008] This invention provides a method for synthesizing narrow bandgap metal telluride semiconductor materials, addressing the shortcomings of existing narrow bandgap metal telluride colloidal quantum dot synthesis techniques. By using phosphine ligands for synergistic activation during the synthesis of metal telluride colloidal quantum dots, the method achieves size and morphology control of the metal telluride colloidal quantum dots. This is achieved by introducing diphenylphosphine to enhance tellurium source activity, increase the supersaturation level during nucleation, and increase the number of nuclei. Furthermore, the method adjusts the particle size of the metal telluride colloidal quantum dots by introducing thiol ligands of different chain lengths.

[0009] To achieve the above objectives, the present invention is implemented through the following technical solution:

[0010] A method for synthesizing a narrow bandgap metal telluride semiconductor material includes the following steps:

[0011] Step S1: Prepare Te precursor solution A;

[0012] Step S2: Prepare metal precursor solution B;

[0013] Step S3: After heating the metal precursor solution B to a specified temperature and stabilizing it for 5 minutes, a specified amount of Te precursor solution A is extracted and injected into the metal precursor solution B; after reacting for a certain time, it is cooled to room temperature to obtain a crude dispersion of narrow bandgap metal telluride colloidal quantum dots.

[0014] Step S4: The crude dispersion of narrow bandgap metal telluride colloidal quantum dots is purified by precipitation to obtain narrow bandgap metal telluride colloidal quantum dots.

[0015] Optionally, the synthesis method for HgTe colloidal quantum dots as the synthesized metal telluride includes the following steps:

[0016] Step A1: Weigh Te powder and add it to a single-necked flask, along with trioctylphosphine (TOP). Stir in a glove box until completely dissolved to obtain a 1 mol / L TOP-Te solution; Te-A: Add diphenylphosphine and thiol ligands to the 1 mol / L TOP-Te solution and disperse thoroughly to obtain phosphine ligand-activated Te precursor solution A; Te-B: Dilute 1 mol / L TOP-Te 5 times with oleylamine to obtain a low-concentration Te precursor solution B; wherein, the thiol ligands include propanethiol, pentathiol, octylthiol, dodecanethiol, hexadecylthiol, and octadecylthiol;

[0017] Step A2: Weigh mercuric halide and add it to a three-necked flask, along with oleylamine. Turn on the magnetic stirrer and evacuate the flask with a vacuum pump. Then, fill the three-necked flask with argon protective gas. Repeat this process N times. After heating to the specified temperature, keep it warm and evacuate the flask again. Keep it warm for later use. This solution is used as mercury precursor solution B. Mercuric halide includes mercuric chloride, mercuric bromide and mercuric iodide.

[0018] Step A3: Using a syringe, extract Te-A and Te-B separately according to the ratio. Quickly inject Te-A into the mercury precursor solution B from Step A2. After reacting for 1 minute, obtain the mercury telluride core solution. Slowly inject TOP-Te into the mercury telluride core solution, specify the reaction time, inject the quencher (tetrachloroethylene, n-octane), and cool to room temperature to obtain the HgTe quantum dot solution.

[0019] Step A4: Draw 3-mercaptopropionic acid into the HgTe quantum dot solution in step A3 using a syringe according to the ratio, and inject it into the HgTe colloidal quantum dot solution with added ligands to obtain a crude dispersion of HgTe colloidal quantum dots.

[0020] Step A5: The crude HgTe colloidal quantum dot dispersion is precipitated and purified, then dissolved in n-octane to obtain an HgTe colloidal quantum dot solution.

[0021] Optionally, in step A1, the molar ratio of Te-A to Te-B is 1:1 to 2.5, and the molar ratio of thiol ligand to Te source is 1:1.

[0022] Optionally, in step A3, the molar ratio of the added Te source to the Hg source is 1:1.5~2; different thiol ligands and reaction temperatures are used to regulate reaction kinetics, thereby regulating grain size.

[0023] Optionally, the synthesis method for CdTe colloidal quantum dots as the synthesized metal telluride includes the following steps:

[0024] Step B1: Weigh Te powder and add it to a single-necked flask, along with trioctylphosphine and diphenylphosphine. Stir in a glove box until completely dissolved to obtain a 1 mol / L TOP-Te solution activated by phosphine ligands. Use this solution as Te precursor solution A.

[0025] Step B2: Weigh cadmium oxide and add it to a three-necked flask, along with octadecene and oleic acid. Turn on the magnetic stirrer and evacuate the flask with a vacuum pump. Then fill the three-necked flask with argon protective gas. Repeat this process N times. After heating to the specified temperature, keep it warm and evacuate the flask again. Keep it warm for later use. This solution is used as cadmium precursor solution B.

[0026] Step B3: Draw Te precursor solution A with a syringe according to the ratio, and quickly inject Te precursor solution A into cadmium precursor solution B from step B2. After a specified reaction time, cool to room temperature to obtain a crude dispersion of CdTe colloidal quantum dots.

[0027] Step B4: The crude CdTe colloidal quantum dot dispersion is purified by precipitation to obtain CdTe colloidal quantum dots.

[0028] Optionally, in step B3, the molar ratio of the added Te source to the Cd source is 1:2; the grain size is controlled by adjusting the reaction temperature.

[0029] Optionally, the synthesis method for PbTe colloidal quantum dots as synthesized metal tellurides includes the following steps:

[0030] Step C1: Weigh Te powder and add it to a single-necked flask, along with trioctylphosphine and diphenylphosphine. Stir in a glove box until completely dissolved to obtain a 1 mol / L TOP-Te solution activated by phosphine ligands. Use this solution as Te precursor solution A.

[0031] Step C2: Weigh lead oxide and add it to a three-necked flask, along with octadecene and oleic acid. Turn on the magnetic stirrer and evacuate the flask with a vacuum pump. Then fill the three-necked flask with argon protective gas. Repeat this process N times. After heating to the specified temperature, keep it warm and evacuate the flask again. Keep it warm for later use. Use this solution as lead precursor solution B.

[0032] Step C3: Draw Te precursor solution A with a syringe according to the ratio, quickly inject Te precursor solution A into lead precursor solution B in step C2, specify the reaction time, add ice hexane and oleic acid for quenching, and cool to room temperature in an ice bath to obtain crude PbTe colloidal quantum dot dispersion.

[0033] Step C4: The crude PbTe colloidal quantum dot dispersion is purified by precipitation to obtain PbTe colloidal quantum dots.

[0034] Optionally, in step C3, the molar ratio of the added Te source to the Pd source is 1:2; the grain size is controlled by adjusting the reaction temperature.

[0035] Optionally, the synthesis method for SnTe colloidal quantum dots as the synthesized metal telluride includes the following steps:

[0036] Step D1: Weigh Te powder and add it to a single-necked flask, along with trioctylphosphine and diphenylphosphine. Stir in a glove box until completely dissolved to obtain a 1 mol / L TOP-Te solution activated by phosphine ligands. Use this solution as Te precursor solution A.

[0037] Step D2: Weigh tin halide and add it to a three-necked flask, along with oleylamine and trioctylamine. Turn on the magnetic stirrer and evacuate the flask with a vacuum pump. Fill the three-necked flask with argon protective gas. Repeat this process N times. After heating to the specified temperature, keep it warm and evacuate the flask again. Keep it warm for later use. Use this solution as tin precursor solution B.

[0038] Step D3: Draw precursor solution A with a syringe according to the ratio, quickly inject precursor solution A into tin precursor solution B in step D2, specify the reaction time, add tetrachloroethylene as a quencher, and cool to room temperature in a water bath to obtain crude SnTe colloidal quantum dot dispersion.

[0039] Step D4: The crude SnTe colloidal quantum dot dispersion is purified by precipitation to obtain SnTe colloidal quantum dots.

[0040] Optionally, the molar ratio of Te source to Sn source added in step D3 is 1:2; the grain size is controlled by adjusting the reaction temperature.

[0041] The beneficial effects of this invention are:

[0042] This invention utilizes a technique to control the size and morphology of metal telluride colloidal quantum dots during their synthesis via phosphine ligand synergistic activation. This is achieved by introducing diphenylphosphine to enhance tellurium source activity, increase supersaturation during nucleation, and raise the number of nuclei. Furthermore, the particle size is adjusted by introducing thiol ligands of varying chain lengths. Specifically, while maintaining other reaction conditions constant, the addition of diphenylphosphine significantly enhances the reactivity of the tellurium precursor, thereby accelerating the nucleation kinetics. This activation leads to a significant increase in the number of crystal nuclei for the metal telluride colloidal quantum dots. Since the total precursor solution concentration remains constant, the increased number of nuclei competes for limited growth materials, resulting in a relative decrease in the available growth materials for each individual nucleus. This limited growth condition effectively inhibits further quantum dot growth, ultimately achieving uniformity in quantum dot size distribution and providing an effective chemical regulation for controlling the size of colloidal quantum dots. Attached Figure Description

[0043] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0044] Figure 1 This is a flowchart of the synthesis process of colloidal quantum dots in the synthesis method of this invention;

[0045] Figure 2 TEM image of HgTe CQDs synthesized in Example 2;

[0046] Figure 3 The image shows TEM images of HgTe CQDs synthesized at the same temperature with different thiol ligands in Example 2.

[0047] Figure 4 TEM image of CdTe CQDs synthesized in Example 3;

[0048] Figure 5 TEM image of PbTe CQDs synthesized in Example 4;

[0049] Figure 6 The image shows a TEM image of the SnTe CQDs synthesized in Example 5. Detailed Implementation

[0050] The embodiments of this application will now be described in detail with reference to the accompanying drawings.

[0051] Example 1

[0052] like Figure 1 As shown, this invention proposes a technique for controlling the size and morphology of metal telluride colloidal quantum dots during the synergistic activation synthesis of these dots using phosphine ligands. The main principle is to enhance the tellurium source activity by introducing diphenylphosphine, thereby increasing the supersaturation level during nucleation and the number of nuclei formed. Furthermore, the particle size is adjusted by introducing thiol ligands of different chain lengths. Specifically, while keeping other reaction conditions constant, the addition of diphenylphosphine significantly improves the reactivity of the tellurium precursor, thus accelerating the nucleation kinetics. This activation leads to a significant increase in the number of crystal nuclei for the metal telluride colloidal quantum dots. Since the total precursor solution concentration remains constant, the increased number of nuclei competes for limited growth materials, resulting in a relative decrease in the growth materials available to each individual nucleus. This limited growth condition effectively inhibits further growth of the quantum dots, ultimately achieving uniformity in their size distribution. This strategy provides an effective chemical regulation for controlling the size of colloidal quantum dots.

[0053] Based on the above principles, the following specific examples will illustrate the process:

[0054] like Figure 1 As shown, this embodiment provides a method for synthesizing narrow bandgap metal telluride semiconductor materials, including the following steps:

[0055] Step S1: Prepare Te precursor solution A;

[0056] Step S2: Prepare metal precursor solution B;

[0057] Step S3: After heating the metal precursor solution B to a specified temperature and stabilizing it for 5 minutes, a specified amount of Te precursor solution A is extracted and injected into the metal precursor solution B; after reacting for a certain time, it is cooled to room temperature, and a crude dispersion of narrow bandgap metal telluride colloidal quantum dots is obtained after the reaction.

[0058] Step S4: The crude dispersion of narrow bandgap metal telluride colloidal quantum dots is purified by precipitation to obtain narrow bandgap metal telluride colloidal quantum dots.

[0059] Example 2

[0060] Based on Example 1, such as Figure 2 As shown, in this embodiment, the synthesized metal telluride colloidal quantum dots are HgTe colloidal quantum dots, synthesized using a two-stage thermal injection method, specifically including the following steps:

[0061] Step A1: Weigh 1 mmol of Te powder and add it to a single-necked flask, along with 10 mL of trioctylphosphine. Stir in a glove box until completely dissolved to obtain a 1 mol / L TOP-Te solution; Te-A: Add diphenylphosphine and thiol ligand to the 1 mol / L TOP-Te solution and disperse thoroughly to obtain phosphine ligand-activated Te precursor solution A; Te-B: Dilute 1 mol / L TOP-Te with oleylamine 5 times to obtain a low-concentration Te precursor solution B;

[0062] The thiol ligands include propanethiol, pentathiol, octylthiol, dodecanethiol, hexadecylthiol, and octadecylthiol; the volume ratio of diphenylphosphine to trioctylphosphine is 0.5~2:20; such as Figure 3 As shown, HgTeCQDs TEMs were synthesized at the same temperature with different thiol ligands.

[0063] Step A2: Weigh 1 mmol of mercuric halide and add it to a 150 mL three-necked flask. At the same time, add 20 mL of oleylamine, turn on the magnetic stirrer and use a vacuum pump to evacuate the flask. Fill the three-necked flask with argon protective gas. Repeat this process 3 times. Heat the flask to 100°C and keep it at that temperature for 30 minutes. Then lower the temperature to 60°C. Use this solution as mercury precursor solution B.

[0064] Mercuric halides include mercuric chloride, mercuric bromide, and mercuric iodide;

[0065] Step A3: Draw 210 μL Te-A and 750 μL Te-B separately with a syringe, and quickly inject Te-A into the mercury precursor solution B from step A2. After reacting for 1 minute, slowly inject 750 μL Te-B over 3 minutes. After reacting for 4 minutes, quickly inject the quencher (tetrachloroethylene, n-octane) and cool to room temperature to obtain HgTe quantum dot solution.

[0066] Step A4: Draw 60 μL of 3-mercaptopropionic acid with a syringe and inject it into the HgTe quantum dot solution from step A3 to obtain a crude dispersion of HgTe colloidal quantum dots with added ligands.

[0067] Step A5: The crude HgTe colloidal quantum dot dispersion was purified by precipitation with isopropanol and then dissolved in n-octane to obtain an HgTe colloidal quantum dot solution.

[0068] Example 3

[0069] Based on Example 1, such as Figure 4 As shown, in this embodiment, the synthesized metal telluride colloidal quantum dots are CdTe colloidal quantum dots, synthesized using a one-step hot-injection method, specifically including the following steps:

[0070] Step B1: Weigh 1 mmol of Te powder and add it to a single-necked flask. At the same time, add 10 mL of trioctylphosphine and 500 μL of diphenylphosphine. Stir in a glove box until completely dissolved to obtain a phosphine ligand-activated TOP-Te solution. Use this solution as Te precursor solution A.

[0071] Step B2: Weigh 0.512g of cadmium oxide and add it to a three-necked flask. At the same time, add 20mL of octadecene and 10mL of oleic acid. Turn on the magnetic stirrer and evacuate the flask with a vacuum pump. Then, fill the three-necked flask with argon protective gas. Repeat this process 3 times. Evacuate the flask at 120℃ for 30 minutes, then purge with argon gas. Then, raise the temperature to 220℃ until the solution becomes a clear solution. Then, raise the temperature to 270℃ and hold for 10 minutes. Use this solution as cadmium precursor solution B.

[0072] Step B3: Use a syringe to draw 2100 μL of precursor solution A and quickly inject it into cadmium precursor solution B from step B2. React for 6 minutes and cool to room temperature to obtain a crude dispersion of CdTe colloidal quantum dots.

[0073] Step B4: Take out the crude product dispersion from step B3, use hexane as solvent and ethanol as antisolvent, centrifuge at 9000 rpm for 5 minutes, repeat 3 times to obtain CdTe colloidal quantum dots.

[0074] Example 4

[0075] Based on Example 1, such as Figure 5 As shown, in this embodiment, the synthesized metal telluride colloidal quantum dots are PbTe colloidal quantum dots, synthesized using a one-step hot-injection method, specifically including the following steps:

[0076] Step C1: Weigh 1 mmol of Te powder and add it to a single-necked flask. At the same time, add 10 mL of trioctylphosphine and 500 μL of diphenylphosphine. Stir in a glove box until completely dissolved to obtain a phosphine ligand-activated TOP-Te solution. Use this solution as Te precursor solution A.

[0077] Step C2: Weigh 0.45g of lead oxide and add it to a three-necked flask, along with 20mL of octadecene and 5mL of oleic acid. Turn on the magnetic stirrer and evacuate the flask with a vacuum pump. Then, fill the three-necked flask with argon protective gas. Repeat this process 3 times. Evacuate the flask at 100℃ for 30 minutes until the solution becomes clear. Then, purge with argon gas and heat to 170℃ and hold for 10 minutes. Use this solution as lead precursor solution B.

[0078] Step C3: Use a syringe to draw 2100 μL of Te precursor solution A and quickly inject it into lead precursor solution B from step C2. React for 5 minutes, cool to 70°C in an ice bath, then inject a mixed solution of 20 mL n-hexane and 5 mL oleic acid as a quenching agent. Cool to room temperature to obtain crude PbTe colloidal quantum dot dispersion.

[0079] Step C4: Take out the crude product dispersion from step C3, use hexane as solvent and methanol as antisolvent, centrifuge at 9000 rpm for 5 minutes, and repeat the centrifugation twice to obtain PbTe colloidal quantum dots.

[0080] Example 5

[0081] Based on Example 1, such as Figure 6 As shown, in this embodiment, the synthesized metal telluride colloidal quantum dots are SnTe colloidal quantum dots, synthesized using a one-step hot-injection method, specifically including the following steps:

[0082] Step D1: Weigh 1 mmol of Te powder and add it to a single-necked flask. At the same time, add 10 mL of trioctylphosphine and 500 μL of diphenylphosphine. Stir in a glove box until completely dissolved to obtain a phosphine ligand-activated TOP-Te solution. Use this solution as Te precursor solution A.

[0083] Step D2: Weigh 0.37g of tin iodide and add it to a three-necked flask. At the same time, add 10mL of oleylamine and 10mL of trioctylamine. Turn on the magnetic stirrer and evacuate the flask with a vacuum pump. Then, fill the three-necked flask with argon protective gas. Repeat this process 3 times. Evacuate the flask at 100℃ for 30 minutes until the solution becomes a clear solution. Then, pass argon gas through the flask and heat it to 120℃ and keep it at that temperature for 10 minutes. Use this solution as tin precursor solution B.

[0084] Step D3: Use a syringe to draw 1100 μL of Te precursor solution A and quickly inject it into the tin precursor solution B in step D2. React for 4 minutes, then inject 20 mL of tetrachloroethylene quencher and cool to room temperature to obtain a crude dispersion of SnTe colloidal quantum dots.

[0085] Step D4: Take out the crude product dispersion from step D3, use hexane as solvent and isopropanol as antisolvent, centrifuge at 9000 rpm for 5 minutes, and centrifuge twice to obtain SnTe colloidal quantum dots.

[0086] Example 6

[0087] Based on all the above embodiments, this invention proposes a technique for preparing HgTe, CdTe, PbTe, and SnTe colloidal quantum dots through phosphine ligand synergistic activation. This technique primarily involves introducing diphenylphosphine to enhance tellurium source activity, increase the supersaturation level during nucleation, and increase the number of nuclei formed. Furthermore, the particle size is adjusted by introducing thiol ligands of different chain lengths. In the synthesis of colloidal quantum dots, the precise control of quantum dot size can be achieved by introducing diphenylphosphine as an activity regulator.

[0088] Specifically, while keeping other reaction conditions constant, the addition of diphenylphosphine significantly enhances the reactivity of the tellurium precursor, thereby accelerating the nucleation kinetics. This activation leads to a significant increase in the number of crystal nuclei in the system. Since the total precursor concentration in the reaction system remains constant, the increased number of crystal nuclei competes for limited growth materials, resulting in a relative decrease in the growth materials available to each individual crystal nucleus. This restricted growth condition effectively inhibits further growth of quantum dots, ultimately achieving uniformity in quantum dot size distribution and providing an effective chemical regulation for controlling the size of colloidal quantum dots.

[0089] Compared with the prior art, the present invention has the following advantages:

[0090] 1. This invention proposes a size control technique in the synthesis of metal telluride colloidal quantum dots. This technique involves introducing diphenylphosphine as an activity regulator to improve the reactivity of the tellurium precursor and increase the nucleation rate. At the same time, it controls the size of the colloidal quantum dots because the growth material is limited and cannot be grown into large-sized crystals, thereby achieving uniformity in the size of the quantum dots.

[0091] 2. This invention can also achieve the control of HgTe colloidal quantum dot size by adding thiol ligands with different chain lengths.

[0092] 3. The method for synthesizing metal tellurides proposed in this invention is applicable not only to the multiple hot injection method but also to the one-step hot injection method.

[0093] 4. The method for controlling the size of metal telluride quantum dots proposed in this invention is also applicable to the synthesis methods of other chalcogenide colloidal quantum dots, and has good universality.

[0094] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope described in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A method for synthesizing a narrow bandgap metal telluride semiconductor material, characterized in that, Includes the following steps: Step S1: Prepare Te precursor solution A; Step S2: Prepare metal precursor solution B; Step S3: After heating the metal precursor solution B to a specified temperature and stabilizing it for 5 minutes, a specified amount of Te precursor solution A is extracted and injected into the metal precursor solution B; after reacting for a certain time, it is cooled to room temperature, and a crude dispersion of narrow bandgap metal telluride colloidal quantum dots is obtained after the reaction. Step S4: The crude dispersion of narrow bandgap metal telluride colloidal quantum dots is purified by precipitation to obtain narrow bandgap metal telluride colloidal quantum dots.

2. The method for synthesizing a narrow bandgap metal telluride semiconductor material according to claim 1, characterized in that, The synthesis method for HgTe colloidal quantum dots, which are synthesized metal tellurides, includes the following steps: Step A1: Weigh Te powder and add it to a single-necked flask, along with trioctylphosphine (TOP). Stir in a glove box until completely dissolved to obtain a 1 mol / L TOP-Te solution; Te-A: Add diphenylphosphine and thiol ligand to the 1 mol / L TOP-Te solution and disperse thoroughly to obtain phosphine ligand activated Te precursor solution A; Te-B: Dilute 1 mol / L TOP-Te with oleylamine 5 times to obtain a low-concentration Te precursor solution B; wherein the thiol ligands include propanethiol, pentathiol, octanethiol, dodecanethiol, hexadecethiol, and octadecethiol. Step A2: Weigh mercuric halide and add it to a three-necked flask, along with oleylamine. Turn on the magnetic stirrer and simultaneously evacuate the flask with a vacuum pump. Then, fill the three-necked flask with argon protective gas. Repeat this process N times. After heating to the specified temperature, keep it warm and evacuate the flask again. Keep it warm for later use. Use this solution as mercury precursor solution B. The mercuric halide includes mercuric chloride, mercuric bromide, and mercuric iodide. Step A3: Using a syringe, extract Te-A and Te-B separately according to the ratio. Quickly inject Te-A into the mercury precursor solution B from Step A2. After reacting for 1 minute, obtain the mercury telluride core solution. Slowly inject TOP-Te into the mercury telluride core solution, specify the reaction time, inject the quencher (tetrachloroethylene, n-octane), and cool to room temperature to obtain the HgTe quantum dot solution. Step A4: Draw 3-mercaptopropionic acid into the HgTe quantum dot solution in step A3 using a syringe according to the ratio, and inject it into the HgTe colloidal quantum dot solution with added ligands to obtain a crude dispersion of HgTe colloidal quantum dots. Step A5: The crude HgTe colloidal quantum dot dispersion is precipitated and purified, then dissolved in n-octane to obtain an HgTe colloidal quantum dot solution.

3. The method for synthesizing a narrow bandgap metal telluride semiconductor material according to claim 2, characterized in that, In step A1, the molar ratio of Te-A to Te-B is 1:1 to 2.5, and the molar ratio of thiol ligand to Te source is 1:

1.

4. The method for synthesizing a narrow bandgap metal telluride semiconductor material according to claim 2, characterized in that, In step A3, the molar ratio of the added Te source to the Hg source is 1:1.5~2; different thiol ligands and reaction temperatures are used to regulate reaction kinetics, thereby regulating grain size.

5. The method for synthesizing a narrow bandgap metal telluride semiconductor material according to claim 1, characterized in that, The method for synthesizing CdTe colloidal quantum dots as metal tellurides includes the following steps: Step B1: Weigh Te powder and add it to a single-necked flask, along with trioctylphosphine and diphenylphosphine. Stir in a glove box until completely dissolved to obtain a 1 mol / L TOP-Te solution activated by phosphine ligands. Use this solution as Te precursor solution A. Step B2: Weigh cadmium oxide and add it to a three-necked flask, along with octadecene and oleic acid. Turn on the magnetic stirrer and evacuate the flask with a vacuum pump. Then fill the three-necked flask with argon protective gas. Repeat this process N times. After heating to the specified temperature, keep it warm and evacuate the flask again. Keep it warm for later use. This solution is used as cadmium precursor solution B. Step B3: Draw Te precursor solution A with a syringe according to the ratio, and quickly inject Te precursor solution A into cadmium precursor solution B from step B2. After a specified reaction time, cool to room temperature to obtain a crude dispersion of CdTe colloidal quantum dots. Step B4: The crude CdTe colloidal quantum dot dispersion is purified by precipitation to obtain CdTe colloidal quantum dots.

6. The method for synthesizing a narrow bandgap metal telluride semiconductor material according to claim 5, characterized in that, In step B3, the molar ratio of the added Te source to the Cd source is 1:2; the grain size is controlled by adjusting the reaction temperature.

7. The method for synthesizing a narrow bandgap metal telluride semiconductor material according to claim 1, characterized in that, The synthesis method for PbTe colloidal quantum dots, which are synthesized metal tellurides, includes the following steps: Step C1: Weigh Te powder and add it to a single-necked flask, along with trioctylphosphine and diphenylphosphine. Stir in a glove box until completely dissolved to obtain a 1 mol / L TOP-Te solution activated by phosphine ligands. Use this solution as Te precursor solution A. Step C2: Weigh lead oxide and add it to a three-necked flask, along with octadecene and oleic acid. Turn on the magnetic stirrer and evacuate the flask with a vacuum pump. Then fill the three-necked flask with argon protective gas. Repeat this process N times. After heating to the specified temperature, keep it warm and evacuate the flask again. Keep it warm for later use. Use this solution as lead precursor solution B. Step C3: Draw Te precursor solution A with a syringe according to the ratio, quickly inject Te precursor solution A into lead precursor solution B in step C2, specify the reaction time, add ice hexane and oleic acid for quenching, and cool to room temperature in a water bath to obtain crude PbTe colloidal quantum dot dispersion. Step C4: The crude PbTe colloidal quantum dot dispersion is purified by precipitation to obtain PbTe colloidal quantum dots.

8. The method for synthesizing a narrow bandgap metal telluride semiconductor material according to claim 7, characterized in that, In step C3, the molar ratio of the added Te source to the Pd source is 1:2; the grain size is controlled by adjusting the reaction temperature.

9. The method for synthesizing a narrow bandgap metal telluride semiconductor material according to claim 1, characterized in that, The method for synthesizing SnTe colloidal quantum dots as metal tellurides includes the following steps: Step D1: Weigh Te powder and add it to a single-necked flask, along with trioctylphosphine and diphenylphosphine. Stir in a glove box until completely dissolved to obtain a 1 mol / L TOP-Te solution activated by phosphine ligands. Use this solution as Te precursor solution A. Step D2: Weigh tin halide and add it to a three-necked flask, along with oleylamine and trioctylamine. Turn on the magnetic stirrer and evacuate the flask with a vacuum pump. Then fill the three-necked flask with argon protective gas. Repeat this process N times. After heating to the specified temperature, keep it warm and evacuate the flask again. Keep it warm for later use. Use this solution as tin precursor solution B. Step D3: Draw Te precursor solution A with a syringe according to the ratio, quickly inject Te precursor solution A into tin precursor solution B in step D2, specify the reaction time, add tetrachloroethylene as a quencher, and cool to room temperature in a water bath to obtain SnTe colloidal quantum dot crude dispersion. Step D4: The crude SnTe colloidal quantum dot dispersion is purified by precipitation to obtain SnTe colloidal quantum dots.

10. The method for synthesizing a narrow bandgap metal telluride semiconductor material according to claim 9, characterized in that, In step D3, the molar ratio of Te source to Sn source is 1:2; the grain size is controlled by adjusting the reaction temperature.

Images