CN107827087B

CN107827087B - Preparation method of regularly bent tellurium nanowires

Info

Publication number: CN107827087B
Application number: CN201711413606.8A
Authority: CN
Inventors: 韩金玲; 吕振瑞
Original assignee: Individual
Current assignee: Individual
Priority date: 2017-12-24
Filing date: 2017-12-24
Publication date: 2020-03-24
Anticipated expiration: 2037-12-24
Also published as: CN107827087A

Abstract

A method for preparing regularly bent tellurium nanowires is characterized in that deionized water is treated by a strong magnetic field, the polarity of the treated deionized water is greatly changed, the deionized water is different from common deionized water when a nanometer material is synthesized, and then the regularly bent tellurium nanowires which cannot be directly obtained before are synthesized under the combined action of a reducing agent and a surfactant, so that the morphology of the tellurium nanowires is widened, and the morphology and the performance of corresponding materials are changed when the tellurium nanowires are used as a hard template agent to synthesize other materials.

Description

Preparation method of regularly bent tellurium nanowires

Technical Field

The invention relates to the technical field of morphology controllable preparation of semiconductor nano materials, in particular to bending controllable synthesis of tellurium nanowires.

Background

Compared with zero-dimensional nanoparticles, quantum dots, two-dimensional nanosheets, three-dimensional macroscopical structures and the like, the one-dimensional nanomaterial has a unique structure, particularly a very high length-diameter ratio, so that the one-dimensional nanomaterial has good properties such as light, electricity, sound and heat, and the properties of the one-dimensional nanomaterial are greatly influenced by the morphology of the one-dimensional nanomaterial, because the dimension of the nanomaterial is less than a certain degree, such as less than 10nm, the nanomaterial shows a strong quantum tunneling effect in a certain direction, and the properties of the nanomaterial are different from those of a conventional block. Thus, extensive research has been conducted on the synthesis thereof.

At present, the synthesis mechanism of the one-dimensional nanowire mainly comprises a VLS (Vapor-Liquid-Solid) growth mechanism proposed by professor Bokrili division and university of California, the main idea is that subsequent atoms to be synthesized are promoted to continuously aggregate and grow through the formation of catalyst Liquid drops on the top of the nanowire, wherein the diameter of the nanowire is mainly controlled by the size of the catalyst Liquid drops; also traditional solvothermal synthesis methods, especially hydrothermal methods, have gained importance therein; besides the above chemical synthesis methods, many researchers have synthesized nanowires with controllable length and shape by physical methods, for example, by using anodic aluminum oxide (AOO) as a hard template, and removing the template after synthesis, suitable nanowires with controllable length and diameter can be obtained.

The tellurium nanowire is a p-type semiconductor one-dimensional nano material, has the band gap energy of 0.35eV, can be widely applied to optoelectronic devices, and has good photoresponse characteristics. For example, in an article entitled "Preparation of fluorescent tellurium Nanowires at Room Temperature" by professor huang Chang of taiwan university, taiwan, 2010, tellurium Nanowires were prepared by adding hydrazine hydrate as a reducing agent to tellurium source (TeO 2), and the length-diameter ratio of the tellurium Nanowires could be well controlled by controlling the reaction time, for example, controlling the reaction time from 40-120min, the length of the prepared tellurium Nanowires increased from 251 to 879nm, while the diameter thereof increased from 8nm to 19 nm. Chinese patent (CN 102910595A) discloses a macro preparation method of superfine tellurium nanowires, which comprises the following steps: reacting sodium tellurite with a reducing agent under the action of a polyvinylpyrrolidone pH value regulator to obtain a reaction mixture; and (3) rapidly cooling the reaction mixture by using cold water to obtain a tellurium nanowire mother solution, and adding a solvent to extract to obtain the tellurium nanowires. After the reaction mixture is obtained by the reaction, the tellurium nanowires are prepared by rapidly cooling the reaction mixture by cold water, and the obtained tellurium nanowires have more uniform quality and thinner diameter; furthermore, the preparation conditions are optimized, so that the method is convenient for mass synthesis and easy to popularize and apply; although the tellurium nanowires prepared by the method can be prepared in a large scale, the prepared nanowires are all linear, and when the tellurium nanowires are used as a template, products inevitably obtained are also linear. It is known that the morphology of nanomaterials, especially nanomaterials with very small dimensions, has a great influence on the properties, and the different morphologies bring about great differences in the properties.

Disclosure of Invention

In order to solve the defects that the synthesized tellurium nanowires are single in appearance and are all linear, the appearance of the tellurium nanowires is widened, and when the tellurium nanowires are used as hard template agents to synthesize other materials, the appearance and the performance of the corresponding materials are changed, the applicant especially provides the following technical scheme for synthesizing the regularly bent tellurium nanowires through a large amount of literature research and continuous experimental improvement.

A method for preparing regularly bent tellurium nanowires, comprising the following steps:

1) weighing a proper amount of tellurium source, dissolving the tellurium source in the treated deionized water, and uniformly stirring to obtain a solution A;

2) adding a proper amount of cationic surfactant into the solution A under the condition of stirring, and continuously stirring to obtain a solution B;

3) transferring the obtained solution B into a three-neck flask, placing the three-neck flask into an oil bath kettle for heating and stirring, adding a proper amount of reducing agent, and introducing nitrogen into a reaction bottle to maintain the inert atmosphere of a reaction system;

4) and under the condition of continuous stirring, after a certain period of time, stopping the reaction, and placing the reaction bottle in cold water to cool to room temperature to obtain the final regularly bent tellurium nanowires.

Preferably, in step 1), the tellurium source includes one or more of tellurium dioxide, sodium tellurite and sodium tellurite.

Preferably, in step 1), the treated deionized water is obtained by subjecting deionized water to a magnetization treatment in a magnetic field of 2-5T, wherein the magnetization is performed in a strong magnetic field center of a Chinese academy of sciences.

Preferably, in step 2), the cationic surfactant is one or more of dodecylglycine, octadecyl trimethyl ammonium chloride and alkyl dimethyl octyl ammonium chloride, and is mainly a quaternary ammonium salt cationic surfactant.

Preferably, in the step 3), the temperature of the oil bath is set to be 100-120 ℃, and the reaction time is 0.5-2 hours.

Preferably, in step 3), the nitrogen flow rate is 10-50 ml/min.

Preferably, in step 3), the reducing agent is one or more of hydrazine hydrate, ammonia water, HI and sodium sulfide.

Preferably, in the step 4), the stirring is performed at a rotation speed of 100-200 rpm.

The principle of the invention is that deionized water is firstly treated by a strong magnetic field, the polarity of the treated deionized water is greatly changed, and when a nano material is synthesized, the nano material is different from common deionized water, and then, under the combined action of a reducing agent and a surfactant, a regularly bent tellurium nanowire which cannot be directly obtained before is synthesized.

Compared with the prior art, the invention has the following beneficial technical effects:

1) the invention creatively uses the magnetized deionized water as a reaction solvent to successfully prepare the regularly bent tellurium nanowire;

2) the invention uses the oil bath pot to provide reaction energy, avoids the defects of the traditional hydrothermal synthesis method, and the hydrothermal synthesis needs to be carried out at high temperature and high pressure, which forms a great obstacle to the expanded production;

3) the invention uses the cationic surfactant, especially the quaternary ammonium salt surfactant, which has strong alkalinity, can maintain the pH value of the reaction system, avoids reusing alkaline substances to adjust the reaction system, optimizes the experimental conditions, makes the reaction simpler, and the prepared tellurium nanowire has very uniformity and the length-diameter ratio of the tellurium nanowire is more than 1000.

Drawings

FIG. 1 is a high magnification SEM photograph of regularly curved tellurium nanowires prepared according to the present invention;

FIG. 2 is a low magnification SEM photograph of a regularly curved tellurium nanowire prepared according to the present invention;

FIG. 3 is an XRD picture of a regularly curved tellurium nanowire prepared according to the present invention;

FIG. 4 SEM photograph of tellurium nanowires prepared in comparative example 1 of the present invention.

Detailed Description

The technical solutions of the present invention are further described below, but not limited thereto, and modifications or equivalent substitutions may be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention.

Example 1

Weighing 0.1g of sodium tellurite, dissolving the sodium tellurite in 100ml of deionized water magnetized by a magnetic field with the field intensity of 2T, and uniformly stirring to obtain a solution A; under the condition of stirring, adding 5g of octadecyl trimethyl ammonium chloride into the solution A, and continuously stirring to obtain a solution B; transferring the obtained solution B into a three-neck flask, placing the three-neck flask in an oil bath kettle at 100 ℃ for heating and stirring, adding 15ml of hydrazine hydrate, and introducing nitrogen into a reaction bottle to maintain the inert atmosphere of a reaction system, wherein the flow rate of the nitrogen is controlled at 100 ml/min; and under the condition of continuous stirring, stopping the reaction after 30min, and placing the reaction bottle in cold water to cool to room temperature to obtain the final regularly bent tellurium nanowires.

Example 2

Weighing 0.1g of tellurium dioxide, dissolving the tellurium dioxide in 100ml of deionized water magnetized by a magnetic field with the field intensity of 3T, and uniformly stirring to obtain a solution A; under the condition of stirring, adding 5g of octadecyl trimethyl ammonium chloride into the solution A, and continuously stirring to obtain a solution B; transferring the obtained solution B into a three-neck flask, placing the three-neck flask in an oil bath kettle at 110 ℃ for heating and stirring, adding 15ml of hydrazine hydrate, and introducing nitrogen into a reaction bottle to maintain the inert atmosphere of a reaction system, wherein the flow rate of the nitrogen is controlled at 100 ml/min; and under the condition of continuous stirring, stopping the reaction after 30min, and placing the reaction bottle in cold water to cool to room temperature to obtain the final regularly bent tellurium nanowires.

Example 3

Weighing 0.5g of tellurium dioxide, dissolving the tellurium dioxide in 200ml of deionized water magnetized by a magnetic field with the field intensity of 3T, and uniformly stirring to obtain a solution A; under the condition of stirring, adding 10g of octadecyl trimethyl ammonium chloride into the solution A, and continuously stirring to obtain a solution B; transferring the obtained solution B into a three-neck flask, placing the three-neck flask in an oil bath kettle at 120 ℃ for heating and stirring, adding 10ml of HI, and introducing nitrogen into a reaction bottle to maintain the inert atmosphere of a reaction system, wherein the flow rate of the nitrogen is controlled at 150 ml/min; and under the condition of continuous stirring, stopping the reaction after 60min, and placing the reaction bottle in cold water to cool to room temperature to obtain the final regularly bent tellurium nanowires.

Comparative example 1

The other steps are the same as the example 1, except that magnetized deionized water is not used as a reaction solvent, and the obtained experimental result is a linear tellurium nanowire.

Claims

1. A method for preparing regularly bent tellurium nanowires is characterized by comprising the following steps: adding a tellurium source, a cationic surfactant, a reducing agent and magnetized deionized water into a three-neck flask in an oil bath pan, stirring and introducing nitrogen to prepare regularly bent tellurium nanowires;

wherein the cationic surfactant is one or more of quaternary ammonium salt cationic surfactants, such as dodecyl glycine, octadecyl trimethyl ammonium chloride and alkyl dimethyl octyl ammonium chloride;

the regularly bent tellurium nanowires have uniform diameters and the magnetized deionized water is magnetized in a magnetic field of 2-5T.

2. The method of claim 1, wherein: the reducing agent is one or more of hydrazine hydrate, ammonia water, HI and sodium sulfide.

3. The method of claim 1, wherein: the temperature of the oil bath is set to be 100-120 ℃, and the reaction time is 0.5-2 hours.