阅读说明：本技术 一种无模板合成微孔硫碳纳米材料的方法及应用 (Method for synthesizing microporous sulfur-carbon nano material without template and application ) 是由 梁海伟 陈智勤 于 2019-12-05 设计创作，主要内容包括：本发明提供了一种无模板合成微孔硫碳纳米材料的方法,包括：S1)将3,3′-联二噻吩、氯化铁与氯仿混合,进行聚合反应,然后除去氯化铁与氯仿,得到微孔共轭聚噻吩；S2)将所述微孔共轭聚噻吩进行高温热解,得到微孔硫碳纳米材料。与现有技术相比,本发明以3,3′-联二噻吩为原料,氯化铁为催化剂,氯仿为溶剂,无模板合成微孔硫碳纳米材料,原料易得,反应条件温和,绿色环保,且制备得到的硫碳纳米材料具有较高的硫含量和比表面积,使其可作为催化剂载体具有较高的活性与稳定性,进而使其在催化反应中具有较好的催化活性。(The invention provides a method for synthesizing a microporous sulfur-carbon nano material without a template, which comprises the following steps: s1) mixing 3,3' -bithiophene, ferric chloride and chloroform, carrying out polymerization reaction, and then removing the ferric chloride and the chloroform to obtain microporous conjugated polythiophene; s2) carrying out high-temperature pyrolysis on the microporous conjugated polythiophene to obtain the microporous sulfur-carbon nano material. Compared with the prior art, the method takes 3,3' -bithiophene as a raw material, ferric chloride as a catalyst and chloroform as a solvent, the microporous sulfur-carbon nano material is synthesized without a template, the raw material is easy to obtain, the reaction condition is mild, the method is green and environment-friendly, and the prepared sulfur-carbon nano material has higher sulfur content and specific surface area, so that the sulfur-carbon nano material can be used as a catalyst carrier and has higher activity and stability, and further has better catalytic activity in catalytic reaction.)

1. A method for synthesizing microporous sulfur-carbon nano material without a template is characterized by comprising the following steps:

s1) mixing 3,3' -bithiophene, ferric chloride and chloroform, carrying out polymerization reaction, and then removing the ferric chloride and the chloroform to obtain microporous conjugated polythiophene;

s2) carrying out high-temperature pyrolysis on the microporous conjugated polythiophene to obtain the microporous sulfur-carbon nano material.

2. The method according to claim 1, wherein the molar ratio of 3,3' -bithiophene, ferric chloride and chloroform is 1: (6-10): (500-800).

3. The method according to claim 1, wherein the step S1) is specifically:

mixing 3,3' -bithiophene with part of chloroform to obtain a first solution;

mixing ferric chloride with the remaining chloroform to obtain a second solution;

mixing the first solution and the second solution, carrying out polymerization reaction, and then removing ferric chloride and chloroform to obtain microporous conjugated polythiophene;

the first solution and the second solution are prepared in no order.

4. The method according to claim 3, wherein the volume ratio of the partial chloroform to the rest chloroform is (1-3): (3-1).

5. The process according to claim 1, characterized in that the polymerization reaction is carried out in a protective atmosphere; the polymerization reaction time is 20-30 h.

6. The method according to claim 1, wherein after the polymerization reaction, ferric chloride and chloroform are removed by adding an alcohol solvent, filtering and washing to obtain the microporous conjugated polythiophene.

7. The method as claimed in claim 1, wherein the temperature of the high-temperature pyrolysis in the step S2) is 600 ℃ to 1000 ℃; the high-temperature pyrolysis time is 1-4 h; the heating rate of the high-temperature pyrolysis is 2-10 ℃/min; the pyrolysis is carried out in a protective atmosphere.

8. The method as claimed in claim 1, wherein the temperature is reduced to 400-600 ℃ at a rate of 2-10 ℃/min after pyrolysis at high temperature, and then the microporous sulfur-carbon nano material is obtained after natural cooling.

9. The microporous sulfur-carbon nanomaterial prepared according to any one of claims 1 to 8.

10. The use of the microporous sulfur-carbon nanomaterial prepared according to any one of claims 1 to 8 as a catalyst support.

Technical Field

The invention belongs to the technical field of nano materials, and particularly relates to a method for synthesizing a microporous sulfur-carbon nano material without a template and application of the microporous sulfur-carbon nano material.

Background

The carbon material has excellent chemical stability, thermal stability, high conductivity and other properties, and is widely applied to many scientific and technical fields including water purification, catalysis, separation, gas sensing, collection, energy storage (fuel cells, supercapacitors, lithium-sulfur batteries) and the like. The doping of sulfur has remarkable effects on the conductivity, alkalinity and oxidation stability of the carbon material, even on the aspect of stabilizing noble metals, and has received wide attention. At the same time, a high specific surface area and a high porosity are also necessary for the carbon material.

At present, the method for synthesizing the porous sulfur-carbon nano material mainly comprises the following steps: 1) polymerizing thiophene to form nonporous polythiophene, mixing the nonporous polythiophene with potassium hydroxide, performing high-temperature pyrolysis, and removing the potassium hydroxide to obtain a porous sulfur-carbon material; 2) and adding the mesoporous silicon spheres in the thiophene polymerization process, pyrolyzing at high temperature, and removing the mesoporous silicon spheres to obtain the porous sulfur-carbon material.

However, the methods for synthesizing the porous sulfur-carbon nano material all need potassium hydroxide as an activating agent or mesoporous silicon spheres as a hard template, and have the advantages of low atom utilization rate, no environmental protection and complex operation.

Disclosure of Invention

In view of the above, the technical problem to be solved by the present invention is to provide a method for template-free synthesis of microporous sulfur-carbon nano-materials and applications thereof.

The invention provides a method for synthesizing a microporous sulfur-carbon nano material without a template, which comprises the following steps:

s1) mixing 3,3' -bithiophene, ferric chloride and chloroform, carrying out polymerization reaction, and then removing the ferric chloride and the chloroform to obtain microporous conjugated polythiophene;

s2) carrying out high-temperature pyrolysis on the microporous conjugated polythiophene to obtain the microporous sulfur-carbon nano material.

Preferably, the molar ratio of the 3,3' -bithiophene, ferric chloride and chloroform is 1: (6-10): (500-800).

Preferably, the step S1) is specifically:

mixing 3,3' -bithiophene with part of chloroform to obtain a first solution;

mixing ferric chloride with the remaining chloroform to obtain a second solution;

mixing the first solution and the second solution, carrying out polymerization reaction, and then removing ferric chloride and chloroform to obtain microporous conjugated polythiophene;

the first solution and the second solution are prepared in no order.

Preferably, the volume ratio of the partial chloroform to the rest chloroform is (1-3): (3-1).

Preferably, the polymerization reaction is carried out in a protective atmosphere; the polymerization reaction time is 20-30 h.

Preferably, after the polymerization reaction, ferric chloride and chloroform are removed by adding an alcohol solvent, filtering and washing to obtain the microporous conjugated polythiophene.

Preferably, the temperature of the high-temperature pyrolysis in the step S2) is 600-1000 ℃; the high-temperature pyrolysis time is 1-4 h; the heating rate of the high-temperature pyrolysis is 2-10 ℃/min; the pyrolysis is carried out in a protective atmosphere.

Preferably, after high-temperature pyrolysis, the temperature is reduced to 400-600 ℃ at the speed of 2-10 ℃/min, and then natural cooling is carried out, so as to obtain the microporous sulfur-carbon nano material.

The invention also provides the microporous sulfur-carbon nano material prepared by the method.

The invention also provides the application of the microporous sulfur-carbon nano material prepared by the method as a catalyst carrier.

The invention provides a method for synthesizing a microporous sulfur-carbon nano material without a template, which comprises the following steps: s1) mixing 3,3' -bithiophene, ferric chloride and chloroform, carrying out polymerization reaction, and then removing the ferric chloride and the chloroform to obtain microporous conjugated polythiophene; s2) carrying out high-temperature pyrolysis on the microporous conjugated polythiophene to obtain the microporous sulfur-carbon nano material. Compared with the prior art, the method takes 3,3' -bithiophene as a raw material, ferric chloride as a catalyst and chloroform as a solvent, the microporous sulfur-carbon nano material is synthesized without a template, the raw material is easy to obtain, the reaction condition is mild, the method is green and environment-friendly, and the prepared sulfur-carbon nano material has higher sulfur content and specific surface area, so that the sulfur-carbon nano material can be used as a catalyst carrier and has higher activity and stability, and further has better catalytic activity in catalytic reaction.

Drawings

FIG. 1 is a scanning electron micrograph of the microporous sulfur-carbon nanomaterial prepared in example 1 of the present invention;

FIG. 2 is a transmission electron micrograph of the microporous sulfur-carbon nanomaterial prepared in example 1 of the present invention;

FIG. 3 is a BET plot of the microporous sulfur-carbon nanomaterial prepared in example 1 of the present invention;

FIG. 4 is a histogram of the mass ratio of elements of the microporous sulfur-carbon nanomaterial prepared in example 1 of the present invention;

FIG. 5 is a BET plot of the microporous sulfur-carbon nanomaterial prepared in example 2 of the present invention;

FIG. 6 is a histogram of the mass ratio of elements of the microporous sulfur-carbon nanomaterial prepared in example 2 of the present invention;

FIG. 7 is a scanning electron microscope photograph of a microporous sulfur-carbon nanomaterial-supported Pt catalyst prepared in example 3 of the present invention;

FIG. 8 is a graph showing the activity of the microporous sulfur-carbon nanomaterial-supported Pt catalyst prepared in example 3 of the present invention in catalyzing formic acid oxidation;

FIG. 9 is a stability graph of the microporous sulfur-carbon nanomaterial-supported Pt catalyst prepared in example 3 of the present invention for catalyzing formic acid oxidation;

FIG. 10 is a graph of the specific surface area of the microporous sulfur-carbon nanomaterial prepared in example 4 of the present invention;

FIG. 11 is a graph of the specific surface area of the microporous sulfur-carbon nanomaterial prepared in example 5 of the present invention;

FIG. 12 is a graph showing the specific surface area of a sulfur-carbon nanomaterial prepared in comparative example 1 of the present invention;

FIG. 13 is a scanning electron micrograph of a sulfur-carbon nanomaterial prepared in comparative example 2 of the present invention.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

The invention provides a method for synthesizing a microporous sulfur-carbon nano material without a template, which comprises the following steps: s1) mixing 3,3' -bithiophene, ferric chloride and chloroform, carrying out polymerization reaction, and then removing the ferric chloride and the chloroform to obtain microporous conjugated polythiophene; s2) carrying out high-temperature pyrolysis on the microporous conjugated polythiophene to obtain the microporous sulfur-carbon nano material.

The present invention is not particularly limited in terms of the source of all raw materials, and may be commercially available.

Mixing 3,3' -bithiophene, ferric chloride and chloroform; the molar ratio of the 3,3' -bithiophene, ferric chloride and chloroform is preferably 1: (6-10): (500-800), more preferably 1: (6-10): (600-800), and more preferably 1: (6-10): (628-785); in some embodiments provided herein, the molar ratio of 3,3' -bithiophene, ferric chloride and chloroform is preferably 1: 6: 628; in some embodiments provided herein, the molar ratio of 3,3' -bithiophene, ferric chloride and chloroform is preferably 1: 8: 628; in other embodiments provided herein, the molar ratio of 3,3' -bithiophene, ferric chloride, and chloroform is preferably 1: 10: 785; in the present invention, it is preferable that 3,3' -bithiophene is first mixed with a part of chloroform, respectively, to obtain a first solution; mixing ferric chloride with the remaining chloroform to obtain a second solution; mixing the first solution with a second solution; wherein the first solution and the second solution are prepared in no sequence; the volume ratio of the part of chloroform to the rest of chloroform is preferably (1-3): (3-1), more preferably (2-3): (2-1), and more preferably 3: 2.

after mixing, carrying out polymerization reaction; the polymerization reaction is preferably carried out in a protective atmosphere; the protective atmosphere is preferably nitrogen; the polymerization is preferably carried out at room temperature; the time of the polymerization reaction is preferably 20-30 h, more preferably 20-28 h, still more preferably 22-26 h, and most preferably 24 h. The 3,3' -bithiophene is polymerized by polymerization reaction to form a three-dimensional network of porous conjugated polythiophene.

Removing ferric chloride and chloroform after the polymerization reaction is finished; the invention preferably removes ferric chloride and chloroform by adding alcohol solvent, filtering and washing; the alcohol solvent is preferably methanol and/or ethanol, more preferably methanol; the volume ratio of the alcohol solvent to the chloroform is preferably (2-3): 1, more preferably 2: 1.

after removal of ferric chloride and chloroform, drying is preferred to obtain microporous conjugated polythiophene.

Carrying out high-temperature pyrolysis on the microporous conjugated polythiophene; the pyrolysis is preferably carried out in a protective atmosphere; the protective atmosphere is preferably nitrogen and/or argon; during the pyrolysis at high temperature, the normal pressure is preferably maintained; the pyrolysis is preferably carried out in a tube furnace; the temperature of the high-temperature pyrolysis (in the invention, the high-temperature pyrolysis temperature refers to the heat preservation temperature) is preferably 600-1000 ℃, more preferably 600-900 ℃, and further preferably 600-800 ℃; the high-temperature pyrolysis time is preferably 1-4 h, and more preferably 2-3 h; the heating rate of the high-temperature pyrolysis is preferably 2-10 ℃/min, more preferably 4-8 ℃/min, still more preferably 4-6 ℃/min, and most preferably 5 ℃/min. In the step, the microporous conjugated polythiophene is directly pyrolyzed, a pyrolysis reaction of dehydrogenation to carbon is carried out along with the rise of pyrolysis temperature, and sulfur atoms and micropores are partially reserved in the pyrolysis process to obtain the microporous sulfur-carbon nano material.

After high-temperature pyrolysis, preferably cooling to 400-600 ℃ at the speed of 2-10 ℃/min, and then naturally cooling to obtain the microporous sulfur-carbon nano material. Wherein, the cooling rate is more preferably 4-8 ℃/min, more preferably 4-6 ℃/min, and most preferably 5 ℃/min; more preferably, the temperature is reduced to 500 ℃ and then naturally cooled.

The method takes 3,3' -bithiophene as a raw material, ferric chloride as a catalyst, chloroform as a solvent, and the microporous sulfur-carbon nano material is synthesized without a template, the raw material is easy to obtain, the reaction condition is mild, and the method is green and environment-friendly, and the prepared sulfur-carbon nano material has higher sulfur content and specific surface area, so that the sulfur-carbon nano material can be used as a catalyst carrier and has higher activity and stability, and further has better catalytic activity in catalytic reaction.

The invention also provides a microporous sulfur-carbon nano material prepared by the method; the specific surface area of the microporous sulfur-carbon nano material is preferably 700-900 m²g^-1More preferably 708 to 858m²g^-1(ii) a The porosity of the microporous sulfur-carbon nano material is preferably 0.5-0.6 cm³g^-1More preferably 0.521 to 0.529cm³g^-1(ii) a The pore diameter of the microporous sulfur-carbon nano material is preferably 0.5-3 nm, more preferably 0.8-2 nm, and further preferably 1-1.5 nm.

The microporous sulfur-carbon nano material synthesized by the method is a good catalyst carrier because the sulfur content and the specific surface area are high, more specific surface areas are provided for catalytic reaction, and more active centers are provided.

The invention also provides an application of the microporous sulfur-carbon nano material prepared by the method as a catalyst carrier.

In the invention, the preparation method of the microporous sulfur-carbon nano material supported catalyst is carried out according to the existing method, and preferably according to the following steps: mixing the microporous sulfur-carbon nano material with a salt for forming a catalyst in an organic solvent, and then removing the solvent to obtain a mixture; calcining the mixture in a reducing atmosphere to obtain a microporous sulfur-carbon nano material supported catalyst; the reducing atmosphere is preferably a mixed gas of an inert gas and hydrogen; the inert gas is preferably argon; the volume content of hydrogen in the mixed gas is preferably 3-10%, and more preferably 5-6%; the high-temperature calcination temperature is preferably 600-1000 ℃, more preferably 600-900 ℃, still more preferably 600-800 ℃, and most preferably 700 ℃; the high-temperature calcination time is preferably 1-4 h, and more preferably 2-3 h; the heating rate of the high-temperature calcination is preferably 2-10 ℃/min, more preferably 4-8 ℃/min, still more preferably 4-6 ℃/min, and most preferably 5 ℃/min. After high-temperature calcination, preferably cooling to 400-600 ℃ at the speed of 2-10 ℃/min, and then naturally cooling to obtain the microporous sulfur-carbon nano material supported catalyst. Wherein, the cooling rate is more preferably 4-8 ℃/min, more preferably 4-6 ℃/min, and most preferably 5 ℃/min; more preferably, the temperature is reduced to 500 ℃ and then naturally cooled.

In order to further illustrate the present invention, the following will describe the method and application of the template-free synthesis of microporous sulfur-carbon nanomaterial provided by the present invention in detail with reference to the examples.

The reagents used in the following examples are all commercially available.