Β-cyc-assisted synthesis of in-v group quantum dot, and synthesis method therefor and use thereof

Abstract

Provided are β-cyc-assisted synthesis of an In-V group quantum dot, and a synthesis method therefor and the use thereof. The method for β-cyc-assisted synthesis of an In-V group quantum dot comprises: preparing a β-cyc-containing precursor solution of an In source and a V group element source, and subjecting it to a hydrothermal reaction; extracting a stock solution after the hydrothermal reaction by using an organic solvent; removing β-cyc from the stock solution, washing same with water and then extracting same; and heating and concentrating same to obtain a high-concentration In-V group quantum dot solution. With regard to the β-cyc-assisted synthesis of an In-V group quantum dot, the In-V group quantum dot synthesized with the assistance of β-cyc is prepared by using the method for β-cyc-assisted synthesis of an In-V group quantum dot. The use of β-cyc-assisted synthesis of an In-V group quantum dot is the use of the β-cyc-assisted synthesis of an In-V group quantum dot in the field of photovoltaics, and the field of photovoltaics comprises solar cells, photoelectrochemical hydrogen production and photoelectric detectors. Compared with traditional synthesis methods, this synthesis method has the advantages of green and environmentally friendly raw materials, a simple and safe process, a simple and convenient device, efficient and economic synthesis, and being low cost.

Description

β-CYC-assisted synthesis of IN-V group quantum dots and their synthesis method and application Technical Field

[0001] The present application relates to the field of In-V family low-dimensional nanomaterials, and in particular to a β-cyc-assisted synthesis of In-V family quantum dots, and a synthesis method and application thereof. Background Art

[0002] In recent years, III-V compound nanomaterials have shown promising applications in solar cells, photoelectrochemical hydrogen production, and photodetectors. Compared to wide-bandgap Al- and Ga-based semiconductors such as AlN and GaN, narrow-bandgap In-based semiconductors such as InP and InAs exhibit stronger light absorption and photoresponse. However, the narrow bandgap of some In-V semiconductors, leading to severe recombination of photogenerated carriers, has limited their further application. The critical size (Bohr exciton radius) for inducing quantum confinement in In-V semiconductors is large, similar to the critical size of quantum dots (10 nm). Therefore, preparing In-V semiconductor quantum dots to induce quantum confinement and widen the bandgap is an effective approach to mitigate this phenomenon.

[0003] Taking InP quantum dots (QDs), the most typical and widely applicable of In-V semiconductor quantum dots, as an example, there are currently the following typical synthesis cases:

[0004] The paper "Gary, Dylan C., et al. "Two-step nucleation and growth of InP quantum dots via magic-sized cluster intermediates." Chemistry of Materials 27.4 (2015): 1432-1441" describes a typical application of InP QDs prepared using P(TMS)3 (tris(trimethylsilyl)phosphine) and In(MA)3 (indium myristate). This method uses the highly reactive P(TMS)3 as a phosphorus source, resulting in highly crystalline InP QDs. However, due to the flammable and explosive nature of P(TMS)3, oxygen must be excluded throughout the reaction, and the high reaction temperature (265°C–370°C) poses significant risks.

[0005] The paper "Byun HJ, Lee JC, Yang H. Solvothermal synthesis of InP quantum dots and their enhanced luminescent efficiency by post-synthetic treatments[J]. Journal of colloid and interface science, 2011, 355(1): 35-41." selected the environmentally friendly and safe phosphorus source P(N(CH3)2)3 instead of the currently widely used highly toxic, flammable and explosive P(TMS)3, and synthesized InP QDs via a solvothermal method. The reaction temperature of this method is relatively low (180℃), but the luminescence intensity of the resulting InP is greatly reduced; and because the solvent used is toluene, oxygen must be isolated throughout the reaction, which is still very dangerous.

[0006] The paper "Xu Z, Li Y, Li J, et al. Formation of size-tunable and nearly monodisperse InP nanocrystals: Chemical reactions and controlled synthesis[J]. Chemistry of Materials, 2019, 31(14): 5331-5341." made a bold innovation by directly using the complexing agent / stabilizer TOP in the previous solution as a phosphorus source and synthesizing InP QDs with good dispersion and uniform particle size in a segmented manner using a hot injection method. The reaction required a high temperature (240-260°C) and argon protection was required throughout the process, so the reaction conditions were still relatively harsh. Technical issues

[0007] The present invention provides a β-cyc-assisted synthesis of In-V group quantum dots, a synthesis method, and an application thereof, to address the high risk and harsh reaction conditions of conventional In-V group semiconductor quantum dot synthesis technology. The technical solution is as follows:

[0008] In a first aspect, embodiments of the present application provide a method for synthesizing In-V quantum dots using β-cyc as an aid, comprising:

[0009] A precursor solution containing β-cyc and an In source and a group V element source is prepared and subjected to a hydrothermal reaction;

[0010] Extracting the original solution after the hydrothermal reaction with an organic solvent;

[0011] Remove β-cyc from the stock solution, wash with water and then extract;

[0012] The solution is heated and concentrated to obtain a high-concentration In-V quantum dot solution. Technical Solutions

[0013] In one embodiment, the method for preparing the precursor solution of the In source and the group V element source containing β-cyc includes: dissolving the In source, the group V element source and β-cyc in a mixed solution of water and ethanol.

[0014] In one embodiment, in the precursor solution of the In source and the group V element source containing β-cyc, the In source is a water-soluble trivalent indium salt.

[0015] In one embodiment, in the precursor solution of the In source and the group V element source containing β-cyc, the In source is InCl3.

[0016] In one embodiment, in the precursor solution containing β-cyc of the In source and the group V element source, the group V element source includes an N source, or a P source, or an As source;

[0017] Among them, melamine is selected as the N source, trioctylphosphine is selected as the P source, and triphenylarsine is selected as the As source.

[0018] In one embodiment, the method for preparing the precursor solution of the In source and the group V element source containing β-cyc comprises: dissolving the In source, the group V element source and β-cyc in a mixed solution of water and ethanol, wherein:

[0019] The specific amount of water-soluble trivalent indium salt is 1.35×10 -3 mol;

[0020] When preparing InN QDs, the specific amount of melamine used was 6.05×10 -4 mol-6.05×10 -3 mol;

[0021] When preparing InP QDs, the specific amount of trioctylphosphine used is 0.3ml-3.0ml;

[0022] When preparing InAs QDs, the specific amount of triphenylarsine used is 6.05×10 -4 mol-6.05×10 -3 mol

[0023] The dosage of β-cyc is 0.1-5g;

[0024] The volume ratio of water to ethanol is 1:1, and the volume of the mixed solution of water and ethanol is 30 ml.

[0025] In one embodiment, the temperature of the hydrothermal reaction is 150°C.

[0026] In one embodiment, the organic solvent is toluene.

[0027] In one embodiment, the reagent for removing β-cyc in the stock solution is amylase or saccharifying enzyme, and the extraction liquid selected after washing is toluene;

[0028] The heating and concentrating temperature is 60-70℃. -1 Concentrate under pa pressure, and the concentration time is 30-60min.

[0029] In a second aspect, an embodiment of the present application provides a β-cyc-assisted synthesis of In-V group quantum dots, which are prepared using any of the above-described β-cyc-assisted synthesis of In-V group quantum dots methods.

[0030] In a third aspect, an embodiment of the present application provides an application of β-cyc-assisted synthesis of In-V group quantum dots, which is to apply the β-cyc-assisted synthesis of In-V group quantum dots in the photovoltaic field, which includes solar cells, photoelectrochemical hydrogen production and photodetectors. Beneficial effects

[0031] (1) This application uses β-cyc to assist in the synthesis of In-V group quantum dots, which is considered to be a convenient, fast and long-term method to solve the technical problems of high risk and harsh reaction conditions in the traditional synthesis of In-V group semiconductor quantum dots. The β-cyc used in this application is a cage-like oligosaccharide structure that can form inclusion complexes with hydrophobic small molecules. During the reaction process, the cage-like structure provides a molecular cage environment for the quantum dots to implant and grow, effectively reducing the activation energy of the reaction between the In source and the V group element source, and allowing In to be grown at a lower reaction temperature. 3+ 、V 5-bonding; at the same time, the molecular cage prevents the agglomeration of quantum dots, making the grown quantum dots more uniform in size. Furthermore, the selected β-cyc has the lowest solubility in the cyc system, and the inclusion complex formed with In-V quantum dots is easily extracted by organic solvents for subsequent purification. Furthermore, the selected group V element sources are all non-polar molecules with highly symmetrical configurations, with the electron cloud concentrated in the central group V atom, making the group V atom highly electronically active. Furthermore, the selected group V element sources do not contain elements other than C, H, and group V elements, and the synthesized quantum dots do not contain impurities of other elements. Within the molecular cage growth environment provided by β-cyc, dopant atoms can be further designed based on the appropriate group V element source, using heavy doping engineering to increase the carrier concentration within the quantum dots or modify their p / n semiconductor properties. Therefore, the method of synthesizing In-V quantum dots using β-cyc as an aid has important application prospects in the synthesis of semiconductor low-dimensional materials and the corresponding device application transformation.

[0032] (2) This application utilizes conventional raw materials to assist in the synthesis, avoiding the harsh synthesis conditions of high temperature and high pressure, and provides a new approach for the preparation of other semiconductor low-dimensional nanomaterials. β-cyc is effectively introduced to assist in the synthesis of In-V quantum dots, and its cage-like oligosaccharide structure is utilized to lower the growth threshold of quantum dots. During the preparation process, the quantum dot particle size can be controlled by adjusting the concentration reaction ratio of the precursor solution. The synthesized quantum dots have a relatively uniform particle size, without large-scale agglomeration, and the luminescence is comparable to that of traditional quantum dots. It has been verified that it can be used to enhance the performance and efficiency of photovoltaic materials.

[0033] (3) Compared with traditional synthesis methods, the β-cyc-assisted synthesis method of In-V quantum dots in this application uses green and environmentally friendly raw materials, a simple and safe process, and a simple device. The synthesis is efficient, economical, and low-cost. At the same time, the quantum dots disclosed in this application have high quantum efficiency and good photovoltaic performance, which can effectively improve the performance of photovoltaic devices. The synthesized In-V quantum dots can be used in photovoltaic devices, significantly enhancing the performance of photovoltaic devices, and provide a new approach for the preparation of other semiconductor low-dimensional nanomaterials.

[0034] The above summary is for illustrative purposes only and is not intended to be limiting in any way. In addition to the illustrative aspects, embodiments and features described above, further aspects, embodiments and features of the present application will be readily apparent by reference to the accompanying drawings and the following detailed description. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] In the accompanying drawings, unless otherwise specified, the same reference numerals throughout the multiple drawings represent the same or similar components or elements. These drawings are not necessarily drawn to scale. It should be understood that these drawings only depict some embodiments disclosed in this application and should not be construed as limiting the scope of this application.

[0036] FIG1 is a process flow chart for synthesizing a β-cyc-assisted synthesis of In-V quantum dots.

[0037] Figure 2 is the Raman curve of InP QDs synthesized in Example 1. The two curves are taken at different positions on the same sample, and both have obvious vibration peaks corresponding to InP.

[0038] Figure 3 shows the PL curve of InP QDs synthesized in Example 1. It can be clearly seen that the band gap is significantly widened compared to bulk InP (1.34 eV).

[0039] FIG4 is a JV (net photocurrent density-output voltage) curve of the device obtained by applying the high-concentration InP quantum dot solution prepared in Example 1 to a solar cell and testing the device.

[0040] FIG5 is a JV (net photocurrent density-output voltage) curve of the device obtained by applying the high-concentration InAs quantum dot solution prepared in Example 2 to a solar cell and testing the device. Implementation Method

[0041] Hereinafter, only certain exemplary embodiments are briefly described. As will be appreciated by those skilled in the art, the described embodiments may be modified in various ways without departing from the spirit or scope of the present application. Therefore, the drawings and description are to be regarded as illustrative in nature and not restrictive.

[0042] In the first aspect, referring to FIG1 , an embodiment of the present application provides a method for synthesizing In-V quantum dots using β-cyc as an aid, comprising:

[0043] Step 101, preparing a precursor solution containing β-cyc of an In source and a group V element source, and performing a hydrothermal reaction;

[0044] Step 102, extracting the stock solution after the hydrothermal reaction with an organic solvent;

[0045] Step 103, removing β-cyc from the stock solution, washing with water and then extracting;

[0046] Step 104 , heating and concentrating to obtain a high-concentration In-V quantum dot solution.

[0047] In one embodiment, a method for preparing a precursor solution of an In source and a group V element source containing β-cyc includes dissolving the In source, the group V element source, and β-cyc in a mixed solution of water and ethanol.

[0048] In one embodiment, in the precursor solution containing β-cyc of an In source and a Group V element source, the In source is a water-soluble trivalent indium salt.

[0049] In one embodiment, in the precursor solution containing β-cyc of an In source and a group V element source, the In source is InCl 3 .

[0050] In one embodiment, in the precursor solution containing β-cyc of an In source and a group V element source, the group V element source includes an N source, a P source, or an As source.

[0051] The Group V element sources selected in this application are all non-polar molecules with highly symmetrical configurations and high activity.

[0052] The nitrogen source used in this application is melamine (commonly known as melamine or protein essence, with a molecular formula of C3H6N6). A comparison of the nitrogen source used in this application with that used in traditional InN QD synthesis is shown in Appendix 1. Unlike other In-V QDs, the nitrogen sources used in InN QDs are mostly inorganic amino or nitrogen-based compounds, which share the common characteristics of violent decomposition upon contact with water and low boiling points. In recent years, some cases have followed the example of InP QD synthesis, using an organic nitrogen source, N(TMS)3, which has a similar structure to P(TMS)3. While organic nitrogen sources are less susceptible to hydrolysis than inorganic nitrogen sources, N(TMS)3 has lower boiling and flash points, still posing a flammable and explosive risk. Furthermore, most organic nitrogen sources have a pungent odor, posing a safety hazard to human health during the synthesis process. Melamine is a stable nitrogen source different from the above nitrogen sources. It is a white, odorless gas with high flash point and boiling point. It is a safe nitrogen source suitable for the nitridation synthesis of InN QDs.

[0053] Raw material flash point and boiling point (at 760 mmHg) price (10,000 yuan) Melamine 325.2 ° C 557.54 ° C 0.0042 / 1g N (TMS) 3189.8 ± 0.0 ° C 189.8 ± 0.0 ° C 0.12 / 1g Li3N decomposes before reaching the flash point and decomposes before reaching the boiling point 0.0145 / 1g NaNH2 decomposes before reaching the boiling point 29.4 ° C 0.0001 / 1g

[0054] Schedule 1

[0055] The P source used in this application is trioctylphosphine (TRI-N-OCTYLPHOSPHINE, referred to as TOP, with a molecular formula of C 24 H51 P). The comparison results of the P source selected in this application and the P source used in the traditional synthesis of InP QDs are shown in Appendix 2. It can be seen that among the traditional P sources, PH3 and PCl3 have low flash points and boiling points, and are highly toxic reagents with high safety risks; P(TMS)3 is slightly less toxic, but has low flash points and boiling points, and is also a flammable and explosive reagent; the prices of tris[2-(diphenylphosphino)ethyl]phosphine, tri(3,5-xylyl)phosphine, and P(TMS)3 are much higher than TOP. It can be seen that TOP is more economical and safer than a series of classic P sources.

[0056] Schedule 2

[0057] The As source used in this application is triphenylarsine (TRIPHENYLARSINE, referred to as AsPh3, with a molecular formula of C 18 H 15 As). The comparison results between the As source selected in this application and the As source used in the traditional synthesis of InAs QDs are shown in Appendix 3. It can be seen that among the traditional As sources, As(TMS)3, As(TMGe)3 and P(TMS)3 are similar, all of which are highly flammable and explosive organic arsenic sources with extremely poor safety. In addition, the current synthesis technology is immature, non-commercially available, and unstable. Tris(dimethylamino)arsenic has a low flash point and boiling point, and its safety and stability are also poor. Inorganic As sources such as Cd2As3 are relatively expensive, and AsH3 has a low flash point and boiling point, and is a highly toxic reagent with a high safety risk. In comparison, the AsPh3 of the present invention, as a new arsenic source, is safe, stable, and low-cost.

[0058] Schedule 3 Best Mode for Carrying Out the Invention

[0059] In this application, a water-soluble trivalent indium salt such as InCl₃ is used as the indium source, and melamine, trioctylphosphine, and triphenylarsine are used as the nitrogen, phosphorus, and asphericity sources for the group V elements, respectively. These materials and novel synthesis methods enable the safe and efficient synthesis of high-quality In-V quantum dots suitable for enhancing the performance of photovoltaic devices. Modes for Carrying Out the Invention

[0060] In one embodiment, a method for preparing a precursor solution of an In source and a Group V element source containing β-cyc comprises dissolving the In source, the Group V element source, and β-cyc in a mixed solution of water and ethanol, wherein:

[0061] The specific amount of water-soluble trivalent indium salt is 1.35×10 -3 mol;

[0062] When preparing InN QDs, the specific amount of melamine used was 6.05×10 -4 mol-6.05×10-3 mol;

[0063] When preparing InP QDs, the specific amount of trioctylphosphine used is 0.3ml-3.0ml;

[0064] When preparing InAs QDs, the specific amount of triphenylarsine used is 6.05×10 -4 mol-6.05×10 -3 mol

[0065] The dosage of β-cyc is 0.1-5g;

[0066] The volume ratio of water to ethanol is 1:1, and the volume of the mixed solution of water and ethanol is 30 ml.

[0067] In one embodiment, the temperature of the hydrothermal reaction is 150°C.

[0068] In one embodiment, the organic solvent is toluene.

[0069] In one embodiment, the reagent for removing β-cyc in the stock solution is amylase or saccharifying enzyme, and the saccharifying enzyme activity is ≥5.0*10 5 u / ml. Enzymatic hydrolysis was performed at 60°C for 30 min. After washing with water, the extraction was performed using toluene as the extraction solvent.

[0070] The heating and concentrating temperature is 60-70℃. -1 Concentrate under pa pressure, and the concentration time is 30-60min.

[0071] In a second aspect, an embodiment of the present application provides a β-cyc-assisted synthesis of In-V group quantum dots, which are prepared using the above-mentioned β-cyc-assisted synthesis of In-V group quantum dots method. Example

[0072] A method for synthesizing In-V quantum dots with the assistance of β-cyc comprises the following steps:

[0073] (1) Preparation of precursor solution: 0.50 g β-cyc, 0.40 g InCl3·4H2O, and 1.50 ml TOP were dissolved in 30 ml of a mixture of water and ethanol with a volume ratio of 1:1.

[0074] (2) Hydrothermal reaction: Place the precursor solution from step (1) in a 50 ml Teflon-lined container, heat to 150°C, and then maintain the temperature for 24 hours. After the temperature is maintained, cool naturally to room temperature.

[0075] (3) Removal of β-cyc: The solution obtained in step (2) was treated with V（溶液） :V （甲苯） After extraction at a ratio of 1:5, take the upper toluene extract and convert the activity to 1.0*10 6 u / ml enzyme, then V （溶液） :V （酶） The enzyme was added in a ratio of 5:1 and enzymatic hydrolysis was carried out at 60°C for 30 minutes. After the enzymatic hydrolysis was completed, deionized water was added for washing and then V （溶液） :V （甲苯） The InP QDs were extracted by adding 1:5.

[0076] (4) Heating and concentrating: The toluene dispersion of InP QDs obtained in step (3) is heated and concentrated at 60°C to obtain a high-concentration InP quantum dot solution after about 1 hour. Example

[0077] A method for synthesizing In-V quantum dots assisted by β-cyc and its application, comprising the following steps:

[0078] (1) Preparation of precursor solution: Take 0.50g β-cyc, 0.40g InCl3·4H2O, and 180mg AsPh3 and dissolve them in 30ml of a 1:1 mixture of water and ethanol.

[0079] (2) Hydrothermal reaction: Place the precursor solution from step (1) in a 50 ml Teflon-lined container, heat to 150°C, and then maintain the temperature for 24 hours. After the temperature is maintained, cool naturally to room temperature.

[0080] (3) Removal of β-cyc: The solution obtained in step (2) was treated with V （溶液） :V （甲苯） After extraction at a ratio of 1:5, take the upper toluene extract and convert the activity to 1.0*10 6 u / ml of saccharifying enzyme, and then V （溶液） :V （酶） Add saccharifying enzyme in a ratio of 5:1 and perform enzymatic hydrolysis at 60℃ for 30min. After the enzymatic hydrolysis is completed, add deionized water for washing and then （溶液） :V （甲苯） The InAs QDs were extracted by adding 1:5.

[0081] (4) Heating and concentrating: The toluene dispersion of InAs QDs obtained in step (3) was heated and concentrated at 60°C to obtain a high-concentration InAs quantum dot solution after about 1 hour. Example

[0082] A method for synthesizing In-V quantum dots assisted by β-cyc and its application, comprising the following steps:

[0083] (1) Preparation of precursor solution: 0.50 g β-cyc, 0.40 g InCl3·4H2O, and 152 mg melamine were dissolved in 30 ml of a mixture of water and ethanol with a volume ratio of 1:1.

[0084] (2) Hydrothermal reaction: Place the precursor solution from step (1) in a 50 ml Teflon-lined container, heat to 150°C, and then maintain the temperature for 24 hours. After the temperature is maintained, cool naturally to room temperature.

[0085] (3) Removal of β-cyc: The solution obtained in step (2) was treated with V （溶液） :V （甲苯） After extraction at a ratio of 1:5, take the upper toluene extract and convert the activity to 1.0*10 6 u / ml of saccharifying enzyme, and then V （溶液） :V （酶） Add saccharifying enzyme in a ratio of 5:1 and perform enzymatic hydrolysis at 60℃ for 30min. After the enzymatic hydrolysis is completed, add deionized water for washing and then （溶液） :V （甲苯） The InN QDs were extracted by adding 1:5.

[0086] (4) Heating and concentrating: The toluene dispersion of InN QDs obtained in step (3) is heated and concentrated at 60°C to obtain a high-concentration InN quantum dot solution after about 1 hour.

[0087] The method for synthesizing In-V quantum dots without the assistance of β-cyc and its application include the following steps:

[0088] (1) Preparation of precursor solution: Take 0.40g InCl3·4H2O and 1.50ml TOP and dissolve them in 30ml of a mixed solution of water and ethanol with a volume ratio of 1:1.

[0089] (2) Hydrothermal reaction: Place the precursor solution from step (1) in a 50 ml Teflon-lined container, heat to 150°C, and then maintain the temperature for 24 hours. After the temperature is maintained, cool naturally to room temperature.

[0090] (3) Heating and concentrating: The toluene dispersion of InP QDs obtained in step (3) is heated and concentrated at 60°C to obtain a high-concentration InP quantum dot solution after about 1 hour.

[0091] The method for synthesizing In-V quantum dots without the assistance of β-cyc and its application include the following steps:

[0092] (1) Preparation of precursor solution: Take 0.40g InCl3·4H2O and 180mg AsPh3 and dissolve them in 30ml of a mixed solution of water and ethanol with a volume ratio of 1:1.

[0093] (2) Hydrothermal reaction: Place the precursor solution from step (1) in a 50 ml Teflon-lined container, heat to 150°C, and then maintain the temperature for 24 hours. After the temperature is maintained, cool naturally to room temperature.

[0094] (3) Heating and concentrating: The toluene dispersion of InAs QDs obtained in step (3) is heated and concentrated at 60°C to obtain a high-concentration InAs quantum dot solution after about 1 hour.

[0095] The method for synthesizing In-V quantum dots without the assistance of β-cyc and its application include the following steps:

[0096] (1) Preparation of precursor solution: Take 0.40g InCl3·4H2O and 152mg melamine and dissolve them in 30ml of a mixed solution of water and ethanol with a volume ratio of 1:1.

[0097] (2) Hydrothermal reaction: Place the precursor solution from step (1) in a 50 ml Teflon-lined container, heat to 150°C, and then maintain the temperature for 24 hours. After the temperature is maintained, cool naturally to room temperature.

[0098] (3) Heating and concentrating: The toluene dispersion of InN QDs obtained in step (3) is heated and concentrated at 60°C to obtain a high-concentration InN quantum dot solution after about 1 hour.

[0099] The InP solution obtained in Example 1 exhibited obvious photoluminescence phenomenon visible to the naked eye under ultraviolet light (emission wavelength of 365nm). The PL curve shown in Figure 3 showed that the luminescence center was approximately 2.2~2.6eV, which was significantly wider than the band gap of bulk InP (1.34eV). At the same time, the Raman curve in Figure 2 also showed that InP should have a band gap of 350cm -1 The samples of Examples 2 and 3 all exhibit infrared luminescence, and their band gaps are significantly broadened compared to the bulk phase. However, the samples of Comparative Examples 1, 2, and 3 do not exhibit photoluminescence, and their solutions show almost no change before and after the reaction.

[0100] Thirdly, embodiments of the present application provide applications of β-cyc-assisted synthesis of In-V quantum dots in the photovoltaic field, particularly in photovoltaic devices. The photovoltaic field includes solar cells, photoelectrochemical hydrogen production, and photodetectors.

[0101] The high-concentration InP quantum dot solution prepared in Example 1 is applied to solar cells. The product needs to be made into a photoelectrode. The specific steps are as follows:

[0102] (1) The n-type GaAs substrate was ultrasonically cleaned with acetone, ethanol, and water for 5 minutes, and then treated with 10% mass fraction dilute hydrochloric acid for 5 minutes.

[0103] (2) Then, 120 nm of gold was evaporated on the unpolished surface of the substrate and annealed in nitrogen at 330 °C for 30 s.

[0104] (3) Perform photolithography of the light-transmitting window on the front side, use positive photoresist to expose for 60 seconds, and develop for 50 seconds to obtain a specific pattern.

[0105] (4) Evaporate 100nmAl2O3 and 120nmAg onto the photolithographic substrate.

[0106] (5) Use acetone to wash away the remaining photoresist, and spin-coat PEDOT solution and high-concentration InP quantum dot solution on the window at a speed of 6000 rpm.

[0107] The high-concentration InAs quantum dot solution prepared in Example 2 is applied to solar cells. The product needs to be made into a photoelectrode. The specific steps are as follows:

[0108] (1) The n-type GaAs substrate was ultrasonically cleaned with acetone, ethanol, and water for 5 minutes, and then treated with 10% mass fraction dilute hydrochloric acid for 5 minutes;

[0109] (2) 120 nm of gold was evaporated on the unpolished surface of the substrate and annealed in nitrogen at 330 °C for 30 s;

[0110] (3) Spin-coat a high-concentration InAs quantum dot solution on the front surface at a speed of 3000 rpm and dry at 50°C;

[0111] (4) The three-layer graphene with PMMA support layer was transferred to the front side, and then the PMMA support layer was removed by soaking in acetone solution for 30 minutes.

[0112] The JV (net photocurrent density - output voltage) curve of the device obtained from the test is shown in Figure 4. Obviously, after the high-concentration InP quantum dot solution prepared in Example 1 is applied to the solar cell, both the open-circuit voltage and short-circuit current are significantly improved, and the PCE (photovoltaic conversion efficiency) is increased from 7.57% to 9.06%.

[0113] The JV (net photocurrent density - output voltage) curve of the device obtained by the test is shown in Figure 5. Obviously, after the high-concentration InAs quantum dot solution prepared in Example 2 is applied to the solar cell, the short-circuit current is significantly improved, and the PCE (photovoltaic conversion efficiency) is increased from 3.34% to 3.55%.

[0114] In the description of this specification, the reference terms "one embodiment," "some embodiments," "example," "specific example," or "some examples" mean that the specific features, structures, materials, or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. Moreover, the specific features, structures, materials, or characteristics described may be combined in any appropriate manner in any one or more embodiments or examples. In addition, those skilled in the art may combine and combine different embodiments or examples described in this specification, as well as features of different embodiments or examples, unless they are mutually inconsistent. Industrial Applicability

[0115] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features being referred to. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature. Throughout the description of this application, "plurality" means two or more, unless otherwise specifically defined.

[0116] Any process or method description in a flow chart or otherwise described herein can be understood to represent a module, segment or portion of code comprising one or more executable instructions for implementing the steps of a specific logical function or process. The scope of the preferred embodiments of the present application includes additional implementations in which the functions may be performed in a different order than shown or discussed, including in a substantially simultaneous manner or in a reverse order depending on the functions involved.

[0117] The logic and / or steps represented in the flowchart or otherwise described herein may be considered, for example, as a sequenced list of executable instructions for implementing the logical functions, and may be embodied in any computer-readable medium for use by, or in conjunction with, an instruction execution system, apparatus, or device (such as a computer-based system, a system including a processor, or other system that can fetch and execute instructions from an instruction execution system, apparatus, or device).

[0118] It should be understood that various parts of the present application can be implemented using hardware, software, firmware, or a combination thereof. In the above embodiments, multiple steps or methods can be implemented using software or firmware stored in a memory and executed by a suitable instruction execution system. All or part of the steps of the above embodiment method can be completed by instructing the relevant hardware through a program, which can be stored in a computer-readable storage medium. When the program is executed, it includes one or a combination of the steps of the method embodiment.

[0119] In addition, the functional units in the various embodiments of the present application may be integrated into a single processing module, or each unit may exist physically separately, or two or more units may be integrated into a single module. The aforementioned integrated modules may be implemented in the form of hardware or in the form of software functional modules. If the aforementioned integrated modules are implemented in the form of software functional modules and sold or used as independent products, they may also be stored in a computer-readable storage medium. The storage medium may be a read-only memory, a magnetic disk, or an optical disk, etc.

[0120] The above description is merely a specific embodiment of the present application, but the scope of protection of the present application is not limited thereto. Any person skilled in the art can easily conceive of various modifications or substitutions within the technical scope disclosed in this application, and such modifications or substitutions should be included within the scope of protection of the present application. Therefore, the scope of protection of the present application should be based on the scope of protection of the claims. Sequence Listing Free Content

[0121] Type your sequence listing free description paragraph here.

Claims

1. A method for synthesizing In-V quantum dots assisted by β-cyc, characterized in that: include: A precursor solution containing β-cyc and an In source and a group V element source is prepared to perform a hydrothermal reaction; Extracting the original solution after the hydrothermal reaction with an organic solvent; Remove β-cyc from the stock solution, wash with water and then extract; The solution is heated and concentrated to obtain a high concentration In-V quantum dot solution.

2. The method for synthesizing In-V quantum dots assisted by β-cyc according to claim 1, characterized in that: The method for preparing the precursor solution containing β-cyc of In source and V group element source comprises: dissolving the In source, V group element source and β-cyc in a mixed solution of water and ethanol.

3. The method for synthesizing In-V quantum dots assisted by β-cyc according to claim 2, characterized in that: In the precursor solution containing β-cyc of the In source and the V group element source, the In source is a water-soluble trivalent indium salt.

4. The method for synthesizing In-V quantum dots assisted by β-cyc according to claim 3, characterized in that: In the precursor solution containing β-cyc of the In source and the V group element source, the V group element source includes an N source, a P source, or an As source; Among them, melamine is selected as the N source, trioctylphosphine is selected as the P source, and triphenylarsine is selected as the As source.

5. The method for synthesizing In-V quantum dots assisted by β-cyc according to claim 4, characterized in that: The method for preparing the precursor solution containing β-cyc of the In source and the V group element source comprises: dissolving the In source, the V group element source and β-cyc in a mixed solution of water and ethanol, wherein: The specific amount of water-soluble trivalent indium salt is 1.35×10 -3 mol; When preparing InN QDs, the specific amount of melamine is 6.05×10 -4 mol-6.05×10 -3 mol; When preparing InP QDs, the specific amount of trioctylphosphine used is 0.3ml-3.0ml; When preparing InAs QDs, the specific amount of triphenylarsine is 6.05×10 -4 mol-6.05×10 -3 mol The dosage of β-cyc is 0.1-5g; The volume ratio of water to ethanol is 1:1, and the volume of the mixed solution of water and ethanol is 30 ml.

6. The method for synthesizing In-V quantum dots assisted by β-cyc according to any one of claims 1 to 5, characterized in that: The temperature of the hydrothermal reaction was 150°C.

7. The method for synthesizing In-V quantum dots assisted by β-cyc according to any one of claims 1 to 5, characterized in that: The organic solvent is toluene.

8. The method for synthesizing In-V quantum dots assisted by β-cyc according to any one of claims 1 to 5, characterized in that: The reagent for removing β-cyc in the stock solution is amylase or saccharifying enzyme, and the extraction liquid selected after washing is toluene; The heating concentration temperature is 60-70℃, -1 Concentrate under pa pressure, and the concentration time is 30-60min.

9. A β-cyc-assisted synthesis of In-V quantum dots, characterized in that: The β-cyc-assisted synthesis of In-V group quantum dots is prepared by the method for synthesizing In-V group quantum dots assisted by β-cyc according to any one of claims 1 to 8.

10. An application of β-cyc assisted synthesis of In-V family quantum dots, characterized in that: The application is to apply the β-cyc-assisted synthesis of In-V group quantum dots described in claim 9 in the photovoltaic field, which includes solar cells, photoelectrochemical hydrogen production and photodetectors.

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