Preparation method of different size indium nanoparticles
By using a one-pot method to prepare indium nanoparticles, controlling temperature and reaction time, and combining ligands such as aliphatic amines and tert-alkylphosphines with centrifugal purification, the problem of synthesizing small-sized indium nanoparticles has been solved, and the preparation of highly active indium nanoparticles has been achieved. This method is suitable for the synthesis of indium-containing metal compounds.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- ZHEJIANG LAB
- Filing Date
- 2023-11-22
- Publication Date
- 2026-06-19
AI Technical Summary
Existing technologies struggle to effectively control and generate nano-indium particles smaller than 10 nm with good dispersion, as they are prone to aggregation or oxidation, making synthesis challenging.
Indium nanoparticles were prepared using a one-pot method. The morphology and size of the nanoparticles were controlled by adjusting the temperature, reaction time, and the use of reducing agents/strong organic bases. Indium nanoparticles of different sizes were prepared by using ligands such as fatty amines and tertiary alkylphosphine, combined with centrifugation purification steps.
Rapid synthesis of uniform indium nanoparticles of different sizes was achieved, which exhibit high reactivity and can serve as excellent precursors for the synthesis of indium-containing metal compounds.
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Figure CN117464018B_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of indium nanoparticle technology, and specifically to a method for preparing indium nanoparticles of different sizes. Background Technology
[0002] Indium nanoparticles possess unique properties such as abundant surface active sites, high electrical conductivity, low melting point, and surface optics, making them widely used in catalysis, electronic devices, and sensing. Recently, the use of uniformly sized, highly active indium nanoparticles as a general platform for preparing metal compounds such as (InN, InP, InAs, In2O3, InSb) has attracted significant attention.
[0003] Typically, the synthesis of indium nanoparticles involves both physical and chemical methods, such as metal vapor deposition, electrochemical reduction, radiation decomposition reduction, chemical reduction, thermal decomposition, chemical liquid deposition, and mechanical grinding. However, not all of these methods can effectively control the size of indium particles and produce well-dispersed small-sized indium particles. Solution methods are considered one of the simplest and most universal methods for synthesizing nano-metal particles, involving the reduction of metal salts or the decomposition of metal precursors. However, for indium nanoparticles smaller than 10 nm, their reactivity and humidity sensitivity are high, and they are prone to aggregation or oxidation, making their synthesis more challenging and requiring more advanced synthesis techniques. Summary of the Invention
[0004] To address the shortcomings of existing technologies, this invention provides a method for preparing indium nanoparticles of different sizes. The method involves dissolving indium chloride in a mixed solution of fatty amine and toluene to prepare an indium precursor solution. Under high temperature conditions, a lithium-based reducing agent / organic strong base of the indium precursor solution is injected into a solvent of tertiary alkylphosphine and fatty amine. By centrifugation, purification, and dispersion, indium nanoparticles with a particle size of 4-100 nm are obtained.
[0005] The technical solution of the present invention is as follows: a method for preparing indium nanoparticles of different sizes, the method specifically including the following preparation steps:
[0006] (1) Indium chloride is added to a mixture of toluene and fatty amine to form a suspension, wherein the volume ratio of toluene to fatty amine is 1-20:1, and the suspension is heated and stirred at 20-200°C until clear to obtain an indium precursor solution, wherein the molar concentration of indium in the indium precursor solution is 0.1-1M;
[0007] (2) Add a solution with a solvent-ligand volume ratio of 4:1 to a three-necked flask and purge the air with an inert gas. Heat the solution to 250°C under an inert atmosphere and then stabilize the temperature to 30-250°C. Inject a reducing agent solution or an organic strong base solution into the solution and continue stirring and heating until the temperature returns to the temperature before the reducing agent is injected. Inject an indium precursor solution and stir to react. Cool the solution to room temperature with an ice-water bath to obtain a product mixture.
[0008] (3) Add 10-100 times the molar amount of indium to the product mixture and stir for 30 min. At this time, the fatty amines and tertiary alkylphosphine ligands on the nano-indium particles in the product mixture will be replaced by oleic acid with stronger coordination ability. Then add a mixture of methanol and toluene with a volume ratio of 2:1 to the product mixture and stir to obtain a turbid solution. The volume ratio of the methanol and toluene mixture to the product mixture is 2:1. Centrifuge the turbid solution at high speed to produce a brown or gray precipitate and a colorless supernatant. Discard the colorless supernatant and redisperse the brown or gray precipitate in toluene or tetrachloroethylene to obtain a stable suspension, which is the colloidal solution of nano-indium particles.
[0009] Specifically, the fatty amines are straight-chain fatty amines and branched-chain fatty amines.
[0010] Specifically, the solvent is a fatty amine or a long-chain olefin.
[0011] Specifically, the ligand is any one of tertiary alkylphosphine, secondary alkylphosphine, aromatic phosphine, or fatty acid.
[0012] Furthermore, the reducing agent raw material in the reducing agent solution is any one of triethyllithium borohydride, sodium borohydride, diisobutylaluminum hydride, and N,N-dimethylethylamine alkyl complex; and the organic strong base solution can replace the reducing agent solution; the raw material in the organic strong base solution is any one of tert-butyllithium and diisopropylaminolithium, and the raw material is an organic base with a pKa greater than 30.
[0013] Furthermore, the concentration of the reducing agent solution or the organic strong base solution is 0.1-2M.
[0014] Furthermore, the molar ratio of the raw material in the reducing agent solution or organic strong alkali solution to the indium in the indium precursor solution is 1-50:1.
[0015] Specifically, the time range for injecting the reducing agent solution or organic strong base solution into the solution and continuing to stir and heat is 1-10 minutes.
[0016] Specifically, the stirring reaction time of the injected indium precursor solution ranges from 0 to 60 minutes.
[0017] Furthermore, the size of the indium nanoparticles is 4-100 nm.
[0018] The beneficial effects of this invention are as follows:
[0019] This invention employs a one-pot method to prepare indium nanoparticles, and the morphology and size of the nanoparticles can be controlled by adjusting temperature, reaction time, and reducing agent / organic strong base. The preparation method of this invention is simple and easy to implement, and can rapidly synthesize indium nanoparticles of different sizes, obtaining uniform indium nanoparticles with a size below 10 nm. It exhibits high reactivity and can be used as an excellent precursor for the synthesis of indium-containing metal compounds. Attached Figure Description
[0020] To more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings used in the description of the embodiments 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.
[0021] Figure 1 These are transmission electron microscope images and particle size distribution diagrams of the indium nanoparticles obtained in Example 1 of this invention.
[0022] Figure 2 These are transmission electron microscope images and particle size distribution diagrams of the indium nanoparticles obtained in Example 2 of this invention.
[0023] Figure 3 These are transmission electron microscope images and particle size distribution diagrams of the indium nanoparticles obtained in Example 3 of this invention.
[0024] Figure 4 These are transmission electron microscope images and particle size distribution diagrams of the indium nanoparticles obtained in Example 4 of this invention.
[0025] Figure 5 These are transmission electron microscope images and particle size distribution diagrams of the indium nanoparticles obtained in Example 5 of this invention. Detailed Implementation
[0026] This invention discloses a method for preparing indium nanoparticles of different sizes. Those skilled in the art can refer to the content of this document and appropriately modify the process parameters to achieve the desired results. It should be particularly noted that all similar substitutions and modifications are obvious to those skilled in the art and are considered to be included in this invention. The preparation method described in this invention has been described through preferred embodiments. Those skilled in the art can obviously modify or appropriately change and combine the preparation method described herein without departing from the content, spirit, and scope of this invention to realize and apply the technology of this invention.
[0027] The present invention will be further described below with reference to specific embodiments:
[0028] like Figure 1 As shown in Example 1: A method for preparing nano-indium particles
[0029] (1) Add 0.4972 g of oleylamine and 0.3450 g of indium chloride (InCl3) to 4 mL of degassed and dehydrated toluene. Heat the mixture at 80 °C and stir until clear to obtain an indium precursor solution.
[0030] (2) Mix 1M of triethyl borohydride tetrahydrofuran solution and n-octyl ether in equal volumes, and remove the tetrahydrofuran solvent by vacuuming in a double-row tube for 1-4 hours to obtain triethyl borohydride n-octyl ether solution.
[0031] (3) Inject 2 ml of oleylamine and 0.5 ml of trioctylphosphine into a three-necked flask, purge with an inert gas to exchange the air in the flask, heat to 250°C and hold for 5 min under an inert atmosphere, then cool to 170°C, inject 2 mL of a 1 M triethyl borohydride solution in n-octyl ether, and continue heating and stirring for 2 min until the temperature stabilizes at 170°C. Quickly inject 0.2 mL of indium precursor solution into the above solution, heat the reaction for 1 min, and then cool the reaction liquid to room temperature in an ice-water bath.
[0032] (4) After the reaction, 0.25 mL of oleic acid was added to the solution and stirred for 10 min. The oleylamine and trioctylphosphine on the indium nanoparticles were replaced by oleic acid. 9.4 mL of a 1:1 mixture of methanol and toluene was added to the resulting solution. The solution became turbid. After centrifugation at 3500 rpm, the bottom precipitate was collected and dispersed again in the methanol and toluene mixture. The centrifugation process was repeated once. Finally, the bottom precipitate was dispersed in the toluene solution to obtain a colloidal solution of indium particles.
[0033] (5) A suitable amount of the above-mentioned indium nanoparticle solution was analyzed by transmission electron microscopy (TEM). The particle size was found to be 6.7 ± 0.1 nm, and the morphology was as follows: Figure 1 As shown in Figure (a), its size distribution is as follows: Figure 1 As shown in Figure (b) of the document.
[0034] like Figure 2 As shown in Implementation Case 2: A method for preparing nano-indium particles
[0035] (1) Add 0.4972 g of oleylamine and 0.3450 g of InCl3 to 4 mL of degassed and dehydrated toluene. Heat the mixture at 80 °C and stir until clear to obtain an indium precursor solution.
[0036] (2) Mix 1M of triethyl borohydride tetrahydrofuran solution and n-octyl ether in equal volumes, and remove the tetrahydrofuran solvent by vacuuming in a double-row tube for 1-4 hours to obtain triethyl borohydride n-octyl ether solution.
[0037] (3) Inject 2 ml of oleylamine and 0.5 ml of trioctylphosphine into a three-necked flask, purge with an inert gas to exchange the air in the flask, heat to 250 °C under an inert atmosphere and hold for 5 min, then cool to 200 °C, inject 2 mL of a 1 M triethyl borohydride solution in n-octyl ether, and continue heating and stirring for 2 min until the temperature stabilizes at 200 °C. Quickly inject 0.2 mL of indium precursor solution into the above solution, heat the reaction for 1 min, and then cool the reaction liquid to room temperature in an ice-water bath.
[0038] (4) After the reaction, 0.25 mL of oleic acid was added to the solution and stirred for 10 min. The oleylamine and trioctylphosphine on the indium nanoparticles were replaced by oleic acid. 9.4 mL of a 1:1 mixture of methanol and toluene was added to the resulting solution. The solution became turbid. After centrifugation at 3500 rpm, the bottom precipitate was collected and dispersed again in the methanol and toluene mixture. The centrifugation process was repeated once. Finally, the bottom precipitate was dispersed in the toluene solution to obtain a colloidal solution of indium particles.
[0039] (5) A suitable amount of the above-mentioned indium nanoparticle solution was analyzed by transmission electron microscopy (TEM). The particle size was found to be 7.1 ± 0.2 nm, and the morphology was as follows: Figure 2 As shown in Figure (a), its size distribution is as follows: Figure 2 As shown in Figure (b) of the document.
[0040] like Figure 3 As shown in Implementation Case 3: A method for preparing nano-indium particles
[0041] (1) Add 0.4972 g of oleylamine and 0.3450 g of InCl3 to 4 mL of degassed and dehydrated toluene. Heat the mixture at 80 °C and stir until clear to obtain an indium precursor solution.
[0042] (2) Mix 1M of triethyl borohydride tetrahydrofuran solution and n-octyl ether in equal volumes, and remove the tetrahydrofuran solvent by vacuuming in a double-row tube for 1-4 hours to obtain triethyl borohydride n-octyl ether solution.
[0043] (3) Inject 2 ml of oleylamine and 0.5 ml of trioctylphosphine into a three-necked flask, purge with an inert gas to exchange the air in the flask, heat to 250 °C under an inert atmosphere and hold for 5 min, then cool to 150 °C, inject 2 mL of a 1 M triethyl borohydride solution in n-octyl ether, and continue heating and stirring for 2 min until the temperature stabilizes at 150 °C. Quickly inject 0.2 mL of an indium precursor solution into the above solution, heat the reaction for 1 min, and then cool the reaction liquid to room temperature in an ice-water bath.
[0044] (4) After the reaction, 0.25 mL of oleic acid was added to the solution and stirred for 10 min. The oleylamine and trioctylphosphine on the indium nanoparticles were replaced by oleic acid. 9.4 mL of a 1:1 mixture of methanol and toluene was added to the resulting solution. The solution became turbid. After centrifugation at 3500 rpm, the bottom precipitate was collected and dispersed again in the methanol and toluene mixture. The centrifugation process was repeated once. Finally, the bottom precipitate was dispersed in the toluene solution to obtain a colloidal solution of indium particles.
[0045] (5) A suitable amount of the above-mentioned indium nanoparticle solution was analyzed by transmission electron microscopy (TEM). The particle size was found to be 30.0 ± 0.7 nm, and the morphology was as follows: Figure 3 As shown in Figure (a), its size distribution is as follows: Figure 3 As shown in Figure (b) of the document.
[0046] like Figure 4 As shown in Implementation Case 4: A method for preparing nano-indium particles
[0047] (1) Add 0.4972 g of oleylamine and 0.3450 g of InCl3 to 4 mL of degassed and dehydrated toluene. Heat the mixture at 80 °C and stir until clear to obtain an indium precursor solution.
[0048] (2) Mix 1M of triethyl borohydride tetrahydrofuran solution and n-octyl ether in equal volumes, and remove the tetrahydrofuran solvent by vacuuming in a double-row tube for 1-4 hours to obtain triethyl borohydride n-octyl ether solution.
[0049] (3) Inject 2 ml of oleylamine and 0.5 ml of trioctylphosphine into a three-necked flask, purge with an inert gas to exchange the air in the flask, heat to 250°C and hold for 5 min under an inert atmosphere, then cool to 170°C, inject 0.8 mL of a 2M solution of lithium diisopropylaminotetrahydrofuran, and continue heating and stirring for 2 min until the temperature stabilizes at 170°C. Quickly inject 0.2 mL of an indium precursor solution into the above solution, heat the reaction for 10 min, and then cool the reaction liquid to room temperature in an ice-water bath.
[0050] (4) After the reaction, 0.25 mL of oleic acid was added to the solution and stirred for 10 min. The oleylamine and trioctylphosphine on the indium nanoparticles were replaced by oleic acid. 9.4 mL of a 1:1 mixture of methanol and toluene was added to the resulting solution. The solution became turbid. After centrifugation at 3500 rpm, the bottom precipitate was collected and dispersed again in the methanol and toluene mixture. The centrifugation process was repeated once. Finally, the bottom precipitate was dispersed in the toluene solution to obtain a colloidal solution of indium particles.
[0051] (5) Take an appropriate amount of the above indium nanoparticle solution for transmission electron microscopy (TEM) analysis. The morphology is as follows: Figure 4As shown in Figure (a), its size distribution is as follows: Figure 4 As shown in Figure (b) of the document.
[0052] like Figure 5 As shown in Implementation Case 5: A method for preparing nano-indium particles
[0053] (1) Add 0.4972 g of oleylamine and 0.3450 g of InCl3 to 4 mL of degassed and dehydrated toluene. Heat the mixture at 80 °C and stir until clear to obtain an indium precursor solution.
[0054] (2) Mix 1M of triethyl borohydride tetrahydrofuran solution and n-octyl ether in equal volumes, and remove the tetrahydrofuran solvent by vacuuming in a double-row tube for 1-4 hours to obtain triethyl borohydride n-octyl ether solution.
[0055] (3) 2 ml of oleylamine and 0.5 ml of trioctylphosphine were injected into a three-necked flask. An inert gas was introduced to exchange the air in the flask. Under an inert atmosphere, the temperature was raised to 250 °C and held for 5 min. Then the temperature was lowered to 200 °C, and 0.8 mL of a 2M solution of diisopropylaminolithium in tetrahydrofuran was injected. The mixture was heated and stirred for another 2 min until the temperature stabilized at 200 °C. 0.2 mL of an indium precursor solution was then rapidly injected into the above solution. The mixture was heated and reacted for 10 min. The reaction mixture was then cooled to room temperature in an ice-water bath.
[0056] (4) After the reaction, 0.25 mL of oleic acid was added to the solution and stirred for 10 min. The oleylamine and trioctylphosphine on the indium nanoparticles were replaced by oleic acid. 9.4 mL of a 1:1 mixture of methanol and toluene was added to the resulting solution. The solution became turbid. After centrifugation at 3500 rpm, the bottom precipitate was collected and dispersed again in the methanol and toluene mixture. The centrifugation process was repeated once. Finally, the bottom precipitate was dispersed in the toluene solution to obtain a colloidal solution of indium particles.
[0057] (5) Take an appropriate amount of the above indium nanoparticle solution for transmission electron microscopy (TEM) analysis. The morphology is as follows: Figure 5 As shown in Figure (a), its size distribution is as follows: Figure 5 As shown in Figure (b) of the document.
[0058] Other embodiments of this application will readily occur to those skilled in the art upon consideration of the specification and practice of the disclosure herein. This application is intended to cover any variations, uses, or adaptations of this application that follow the general principles of this application and include common knowledge or customary techniques in the art not disclosed herein.
[0059] It should be understood that this application is not limited to the precise structure described above and shown in the accompanying drawings, and various modifications and changes can be made without departing from its scope.
Claims
1. A method for preparing different sized nanoparticles of indium, comprising: This method specifically includes the following preparation steps: (1) Indium chloride is added to a mixture of toluene and fatty amine to form a suspension, wherein the volume ratio of toluene to fatty amine is 1:20, and the suspension is heated and stirred at 20-200°C until clear to obtain an indium precursor solution, wherein the molar concentration of indium in the indium precursor solution is 0.1-1 M; (2) Add a solution with a solvent-to-ligand volume ratio of 4:1 to a three-necked flask and purge the air with an inert gas. Heat the solution to 250°C under an inert atmosphere and then stabilize the temperature to 30-250°C. Inject a reducing agent solution or an organic strong base solution into the solution and continue stirring and heating until the temperature returns to the temperature before the reducing agent is injected. Inject an indium precursor solution and stir to react. Cool the solution to room temperature with an ice-water bath to obtain a product mixture. The solvent is an aliphatic amine or a long-chain olefin. The ligand is a tert-alkylphosphine. The reducing agent raw material in the reducing agent solution is any one of triethyllithium borohydride, sodium borohydride, or diisobutylaluminum hydride. The organic strong base solution can replace the reducing agent solution. The raw material in the organic strong base solution is any one of tert-butyllithium and diisopropylaminolithium, and the pKa of the raw material is greater than 30. (3) Add 10-100 times the molar amount of indium to the product mixture and stir for 30 min. At this time, the fatty amines and tertiary alkylphosphine ligands on the nano-indium particles in the product mixture will be replaced by oleic acid with stronger coordination ability. Then add a mixture of methanol and toluene with a volume ratio of 2:1 to the product mixture and stir to obtain a turbid solution. The volume ratio of the methanol and toluene mixture to the product mixture is 2:
1. Centrifuge the turbid solution at high speed to produce a brown or gray precipitate and a colorless supernatant. Discard the colorless supernatant and redisperse the brown or gray precipitate in toluene or tetrachloroethylene to obtain a stable suspension, which is the colloidal solution of nano-indium particles.
2. The method for preparing indium nanoparticles of different sizes according to claim 1, characterized in that, The fatty amines are straight-chain fatty amines and branched-chain fatty amines.
3. The method for preparing indium nanoparticles of different sizes according to claim 1, characterized in that, The concentration of the reducing agent solution or organic strong base solution is 0.1-2 M.
4. The method for preparing indium nanoparticles of different sizes according to claim 1, characterized in that, The molar ratio of the raw material in the reducing agent or strong organic alkali to that indium in the indium precursor solution is 1-50:
1.
5. The method for preparing indium nanoparticles of different sizes according to claim 1, characterized in that, The process of injecting the reducing agent solution or organic strong alkali solution into the solution and continuing to stir and heat for 1-10 minutes is described.
6. The method for preparing indium nanoparticles of different sizes according to claim 1, characterized in that, The stirring reaction time for the injected indium precursor solution ranges from 0 to 60 minutes.
7. The method for preparing indium nanoparticles of different sizes according to claim 1, characterized in that, The size of the indium nanoparticles is 4-100 nm.