阅读说明：本技术 一种杂原子掺杂的多功能碳基电极材料的制备方法及其应用 (Preparation method and application of heteroatom-doped multifunctional carbon-based electrode material ) 是由 高书燕 陈晨 田苗 陈野 蒋凯 于 2020-12-18 设计创作，主要内容包括：本发明公开了一种杂原子掺杂的多功能碳基电极材料的制备方法及其应用,富含氮磷元素的六氯环三磷腈和富含硫元素的双酚硫作为聚合物单体加入到乙腈和去离子水的混合溶液中,加入缚酸剂三乙胺,随后加入碱式碳酸锌为活化剂,先超声处理30min,之后搅拌12h,离心分离得到沉淀即为物料A；将物料A转移至瓷舟中并放置于管式炉中,在惰性气体保护下由室温经过60min升温至300℃保持120min,再以3℃/min的升温速率升温至800℃保持120min,然后自然降温至室温得到物料B；再用盐酸溶液将物料B洗涤2-3次,然后于105℃干燥12h得到目标产物。本发明简单且易操作,更好地推进了超级电容器,氧还原反应以及电芬顿法降解有机污染物的大规模应用。(The invention discloses a preparation method and application of a heteroatom-doped multifunctional carbon-based electrode material, wherein hexachlorocyclotriphosphazene rich in nitrogen and phosphorus elements and bisphenol sulfur rich in sulfur elements are taken as polymer monomers and added into a mixed solution of acetonitrile and deionized water, acid-binding agent triethylamine is added, then basic zinc carbonate is added as an activating agent, ultrasonic treatment is firstly carried out for 30min, then stirring is carried out for 12h, and centrifugal separation is carried out to obtain a precipitate, namely a material A; transferring the material A into a porcelain boat, placing the porcelain boat in a tube furnace, heating the porcelain boat from room temperature to 300 ℃ for 120min after 60min under the protection of inert gas, heating the porcelain boat to 800 ℃ at the heating rate of 3 ℃/min for 120min, and naturally cooling the porcelain boat to room temperature to obtain a material B; and washing the material B for 2-3 times by using a hydrochloric acid solution, and then drying at 105 ℃ for 12h to obtain a target product. The method is simple and easy to operate, and the large-scale application of the super capacitor, the oxygen reduction reaction and the electro-Fenton method for degrading organic pollutants is promoted better.)

1. A preparation method of a heteroatom-doped multifunctional carbon-based electrode material is characterized by comprising the following specific steps:

step S1: adding a polymer monomer, an acid-binding agent and an activating agent into a mixed solvent of acetonitrile and water, carrying out ultrasonic treatment for 30min, then stirring for 12h, and carrying out centrifugal separation to obtain a material A, wherein the polymer monomer is hexachlorocyclotriphosphazene and bisphenol sulfur, the acid-binding agent is triethylamine, and the activating agent is basic zinc carbonate;

step S2: transferring the material A obtained in the step S1 to a nickel boat, placing the nickel boat in a tube furnace, heating to 330 ℃ from room temperature for 60min in an inert gas atmosphere, keeping the temperature for 120min, heating to 600 ℃ at a heating rate of 3 ℃/min, keeping the temperature for 120min, and naturally cooling to room temperature to obtain a material B;

step S3: washing the material B obtained in the step S2 with 2M hydrochloric acid solution for 2-3 times, and drying at 105 ℃ for 12h to obtain a target product nitrogen sulfur phosphorus tri-doped carbon-based catalyst, wherein the specific surface area of the nitrogen sulfur phosphorus tri-doped carbon-based catalyst is 800-1600M²And/g, and contains a large number of micropores and mesopores.

2. The method of claim 1, wherein the heteroatom-doped multifunctional carbon-based electrode material comprises: in the step S1, the feeding molar ratio of the polymer monomer, the acid binding agent and the activating agent is 1:9: 0.5-5.

3. The method of claim 1, wherein the heteroatom-doped multifunctional carbon-based electrode material comprises: in the step S1, the molar ratio of hexachlorocyclotriphosphazene to bisphenol sulfur in the polymer monomer is 1: 3.

4. The method of claim 1, wherein the heteroatom-doped multifunctional carbon-based electrode material comprises: in step S2, the inert gas is one or more of nitrogen or argon.

5. The preparation method of the heteroatom-doped multifunctional carbon-based electrode material according to claim 1, which is characterized by comprising the following specific steps:

step S1: adding 121.8mg of hexachlorocyclotriphosphazene, 277.8mg of polymerized monomer bisphenol sulfur, 30mL of acid-binding agent triethylamine and 150mg of activator basic zinc carbonate into a mixed solvent of acetonitrile and water, carrying out ultrasonic treatment for 30min, then stirring for 12h, and carrying out centrifugal separation to obtain a material A;

step S2: transferring the material A obtained in the step S1 to a nickel boat, placing the nickel boat in a tube furnace, heating to 330 ℃ from room temperature for 60min in an inert gas atmosphere, keeping the temperature for 120min, heating to 800 ℃ at a heating rate of 3 ℃/min, keeping the temperature for 120min, and naturally cooling to room temperature to obtain a material B;

step S3: and (4) washing the material B obtained in the step (S2) with 2M hydrochloric acid solution for 2-3 times, and drying at 105 ℃ for 12h to obtain a target product, namely the nitrogen sulfur phosphorus tri-doped multifunctional carbon-based electrode material, wherein the heteroatom-doped carbon catalyst is firstly tested for the capacitance characteristics under acidic and alkaline conditions, and shows the performance of an ultra-high super capacitor.

6. The heteroatom-doped multifunctional carbon-based electrode material prepared by the method according to any one of claims 1 to 5 is used as an electrode material of a supercapacitor, and a cathode catalyst of alkaline oxygen reduction and acidic electro-Fenton for treating organic wastewater.

Technical Field

The invention belongs to the technical field of synthesis of porous carbon materials, and particularly relates to a heteroatom-doped multifunctional carbon material for organic pollution degradation of a super capacitor, oxygen reduction and electro-Fenton, a method for preparing a multi-level pore coexisting heteroatom-doped carbon electrode material by using hexachlorocyclotriphosphazene rich in nitrogen and phosphorus and bisphenol sulfur rich in sulfur as polymer monomers and a heteroatom dopant through one-step simple polymerization reaction, and application of the method.

Background

Energy crisis and environmental pollution are major problems facing human beings at present, and the development of society and the progress of industry are seriously hindered. At present, the development of energy storage materials for economic and environmental protection and efficient water pollution treatment technologies is urgently needed to meet the current increasing demand. Super capacitors (SCs for short) and fuel cells (FCs for short) have a wide prospect in terms of energy conversion and storage, which is helpful for solving the energy crisis to realize sustainable production. The rapid development of the industry is accompanied by the introduction of a large amount of organic matters into the production, which leads to the discharge of a large amount of organic matters into the water body and seriously threatens the health of people. Industrial waste water, mainly high-toxic, difficult-to-degrade organic pollutants, has become a non-trivial problem threatening human health. Currently, the mature water treatment technologies include physical adsorption, membrane separation and electro-Fenton (electro-Fenton, abbreviated as EF). Among them, researchers widely apply EF technology, which has fast response speed, low toxicity and reduced sludge generation, to the treatment of industrial wastewater, so that the EF method for treating wastewater has become a hot spot of research of scientists. At present, a lot of reports are made on single-function electrode materials of SCs/ORR/EF, but few reports are made on materials with energy storage and catalysis functions. Therefore, researchers have been working on the design and synthesis of multifunctional carbon materials with hopes of alleviating the energy crisis and thoroughly solving the water pollution problem.

At present, heteroatom doped carbon materials are widely applied to electrocatalytic systems related to energy and environment due to the fact that the carbon materials have ultrahigh specific surface, hierarchical pore structures, good electrical conductivity and abundant heteroatoms, and particularly, super capacitors, oxygen reduction fuel cells and electro-Fenton systems are used for treating organic wastewater. The nitrogen-doped carbon-based material has an adjustable electronic structure and abundant electrochemical active sites, so that the pseudocapacitance and ORR electrocatalytic activity of the material are improved, and great attention is paid to researchers. According to the reports of documents, the introduction of P atoms into a carbon framework can not only improve the capacitive performance of the carbon framework in the aspect of energy storage, but also widen the voltage window, further improve the energy density of the carbon framework, and in terms of catalysis, the doping of phosphorus atoms can activate the structure of surrounding carbon atoms, and oxygen reduction reaction creates abundant active sites.WuIt was found that the thiophene-S group helps to improve the charge storage capability of SC and ORR selectivity and H under acidic conditions₂O₂Selectivity of formation. In summary, the heteroatom-doped carbon material has multiple synergistic effects, and especially the ternary doping of N, S and P can synergistically generate a unique electronic structure, and further improve the capacitance characteristics and the electrocatalytic activity of the carbon substrate. Recently, Covalent Triazine Polymers (CTPs) with ultra-high thermal stability, doping of various elements and ultra-high specific surface area have been considered as ideal heteroatom-doped precursors. In addition, incorporation of various non-metallic dopants (e.g., N, B, F, P, S, etc.) into the carbon backbone can create a rich array of heteroatom electrochemically active sites. Therefore, the heteroatom-doped carbon-based material prepared by utilizing the polymerization monomer rich in the heteroatoms through one-step simple polymerization reaction is an effective way for realizing the energy storage and catalysis characteristics of the electrode material. The electron enrichment of sulfur atom endows CTP with unique physical and chemical characteristics, and satisfies the physical and chemical structures of energy storage and catalytic materials. However, the current studies on the CTP-derived heteroatom-doped carbon-based material are relatively few, and particularly in the fields of energy storage and catalysis, the CTP-derived heteroatom-doped carbon-based material has a relatively high research prospect. Based on our topic groupsOn the basis of previous researches on electrochemistry and structure-activity relationship of energy storage and catalytic materials, the preparation of the heteroatom-doped porous carbon material is realized through a one-step simple polymerization reaction, and the electrode material has outstanding energy storage and catalytic properties.

Disclosure of Invention

The technical problems solved by the invention are respectively as follows: firstly, based on the previous research work of the subject group, the electrochemical performance of an electrode material is tested by using a rotary disk electrode, theoretical guidance is provided for the application of screening the electrode material, and the electrode material with two electron transfers is used for electro-Fenton through calculation; the material which generates the four-electron transfer is used for the oxygen reduction fuel cell, blind trial work is improved to theoretical guidance, and the trial work of screening the electrode material is greatly simplified. Secondly, through the development of the work, the preparation method for preparing the heteroatom-doped multifunctional carbon-based catalyst with coexisting hierarchical pores by using the condensation reaction heteroatom self-doping strategy, which is simple in preparation process, low in cost and environment-friendly, is provided, hexachlorocyclotriphosphazene and bisphenol sulfur are used as polymerization monomers, triethylamine is used as an acid-binding agent, basic zinc carbonate is used as an activating agent to modify a carbon material, and the basic zinc carbonate is used as an activating agent and is decomposed into ZnO and H in the calcining process₂O、CO、CO₂、NO_xAnd the like; and the bisphenol sulfur rich in the heteroatom is pyrolyzed at high temperature to release H₂And reacting small molecular gases such as S and the like with ZnO to generate ZnS, and removing the ZnS through acid washing to prepare the carbon-based material with the rich pore structure. In order to investigate the influence of temperature on the heteroatom content and the pore structure of the carbon material, the invention tries to adjust the activation temperature to investigate the influence of the temperature on the performance of the carbon-based electrode material, the preparation method is simple and easy to operate, and the large-scale application of the supercapacitor, the oxygen reduction reaction and the organic pollutant degradation by the electro-Fenton method is promoted.

The invention adopts the following technical scheme for solving the technical problems, and the preparation method of the heteroatom-doped multifunctional carbon-based catalyst is characterized by comprising the following specific processes:

step S1: adding a polymer monomer, an acid-binding agent and an activating agent into a mixed solvent of acetonitrile and water, carrying out ultrasonic treatment for 30min, then stirring for 12h, and carrying out centrifugal separation to obtain a material A, wherein the polymer monomer is hexachlorocyclotriphosphazene and bisphenol sulfur, the acid-binding agent is triethylamine, and the activating agent is basic zinc carbonate;

step S2: transferring the material A obtained in the step S1 to a nickel boat, placing the nickel boat in a tube furnace, heating to 330 ℃ from room temperature for 60min in an inert gas atmosphere, keeping the temperature for 120min, heating to 600 ℃ at a heating rate of 3 ℃/min, keeping the temperature for 120min, and naturally cooling to room temperature to obtain a material B;

step S3: washing the material B obtained in the step S2 with 2M hydrochloric acid solution for 2-3 times, and drying at 105 ℃ for 12h to obtain the nitrogen sulfur phosphorus tri-doped carbon-based catalyst with controllable target product pore size, wherein the specific surface area of the nitrogen sulfur phosphorus tri-doped carbon-based electrode material is 800-²And/g, and contains a large number of micropores and mesopores.

Preferably, the feeding molar ratio of the polymer monomer, the acid-binding agent and the activating agent in the step S1 is 1:3: 0.5-5.

Preferably, the molar ratio of hexachlorocyclotriphosphazene to bisphenol sulfur in the polymer monomers in step S1 is 1: 3.

Preferably, the inert gas in step S2 is one or more of nitrogen or argon.

The preparation method of the heteroatom-doped multifunctional carbon-based electrode material is characterized by comprising the following specific steps of:

step S1: adding 121.8mg of hexachlorocyclotriphosphazene, 277.8mg of bisphenol sulfur (a polymeric monomer), 30mL of triethylamine (an acid-binding agent) and 150mg of basic zinc carbonate (an activating agent) into a mixed solvent of acetonitrile and water, carrying out ultrasonic treatment for 30min, then stirring for 12h, and carrying out centrifugal separation to obtain a material A;

step S2: transferring the material A obtained in the step S1 to a nickel boat, placing the nickel boat in a tube furnace, heating to 330 ℃ from room temperature for 60min in an inert gas atmosphere, keeping the temperature for 120min, heating to 800 ℃ at a heating rate of 3 ℃/min, keeping the temperature for 120min, and naturally cooling to room temperature to obtain a material B;

step S3: and (4) washing the material B obtained in the step (S2) with 2M hydrochloric acid solution for 2-3 times, and drying at 105 ℃ for 12h to obtain a target product, namely the nitrogen sulfur phosphorus tri-doped multifunctional carbon-based electrode material, wherein the heteroatom-doped carbon electrode material is firstly tested for the capacitance characteristics under acidic and alkaline conditions, and shows the performance of an ultra-high super capacitor.

The heteroatom-doped multifunctional carbon-based electrode material disclosed by the invention is applied as an electrode material of a supercapacitor or used as a cathode catalyst of electro-Fenton under alkaline oxygen reduction and acidic conditions for treating organic wastewater.

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

1. according to the invention, hexachlorocyclotriphosphazene rich in nitrogen and phosphorus elements and bisphenol sulfur rich in sulfur elements are introduced as a polymer monomer and a heteroatom dopant, and basic zinc carbonate is used as an activating agent to enable the material to have a rich pore structure, so that the specific surface area and the pore volume of the carbon material are increased, more active sites are exposed, and the catalytic degradation activity of the material is enhanced;

2. according to the invention, hexachlorocyclotriphosphazene and bisphenol sulfur are used as a polymer monomer and a heteroatom dopant, and heteroatoms are introduced in situ on the basis of a carbon precursor, so that the hydrophilicity and the conductivity of the carbon material are improved, more active sites are exposed, and the electrochemical performance of the prepared carbon material is further enhanced;

3. the specific surface area of the heteroatom-doped carbon electrode material prepared by the invention is 800-1600m²And/g, the carbon material is regulated under the action of basic zinc carbonate, so that the carbon material is regulated from an original single pore structure to a hierarchical pore structure containing a large number of micropores and small pore diameters, and the carbon material is applied to an electro-Fenton system as a cathode material, can efficiently degrade organic pollutants, does not cause secondary pollution in the using process, and is environment-friendly.

Drawings

FIG. 1 is a scanning electron microscope image of a field emission microscope of a nitrogen-sulfur-phosphorus triple-doped carbon-based electrode material C3 prepared in example 3;

FIG. 2 is an energy spectrum of a N, S, P triple doped carbon-based electrode material C3 prepared in example 3;

FIG. 3 is a graph of a nitrogen adsorption and desorption curve and a pore size distribution diagram of a nitrogen-sulfur-phosphorus triple-doped carbon-based electrode material C3 prepared in example 3;

FIG. 4 is a charge-discharge diagram of a nitrogen-sulfur-phosphorus triple-doped carbon-based electrode material C3 prepared in example 3 for a supercapacitor;

FIG. 5 is a cyclic voltammogram of a N, S, P triple doped carbon based electrode material C3 prepared in example 3 for use in an oxygen reduction fuel cell;

FIG. 6 is the electron transfer number diagram of the N-S-P triple-doped carbon-based electrode material C3 prepared in example 3 for the EF system

FIG. 7 is a graph showing the efficiency of degrading methylene yellow of the N-S-P triple-doped carbon-based electrode materials prepared in examples 1-4.

Detailed Description

The present invention is described in further detail below with reference to examples, but it should not be construed that the scope of the above subject matter of the present invention is limited to the following examples, and that all the technologies realized based on the above subject matter of the present invention belong to the scope of the present invention.

Example 1

Step S1: adding 121.8mg of hexachlorocyclotriphosphazene, 277.8mg of bisphenol sulfur (a polymeric monomer), 30mL of triethylamine (an acid-binding agent) and 150mg of basic zinc carbonate (an activating agent) into a mixed solvent of acetonitrile and water, carrying out ultrasonic treatment for 30min, then stirring for 12h, and carrying out centrifugal separation to obtain a material A1;

step S2: transferring the material A1 to a nickel boat, placing the nickel boat in a tube furnace, heating to 330 ℃ from room temperature for 60min in a nitrogen atmosphere with the flow rate of 100mL/min, keeping the temperature for 120min, heating to 600 ℃ at the heating rate of 3 ℃/min, keeping the temperature for 120min, and naturally cooling to room temperature to obtain a material B1;

step S3: and washing the material B1 with 2M hydrochloric acid solution for 2-3 times, and drying at 105 ℃ for 12h to obtain a target product, namely, the nitrogen-sulfur-phosphorus tri-doped carbon-based catalyst C1, wherein the nitrogen-sulfur-phosphorus tri-doped carbon-based electrode material C1 is used as a cathode catalyst of an electro-Fenton system to degrade 200mL of mixed dyes (methyl blue, methyl orange, methyl red and rhodamine B) with the concentration of 10mg/L, and the degradation efficiency is 79.6% after 150 min.

Example 2

Step S1: adding 121.8mg of hexachlorocyclotriphosphazene, 277.8mg of bisphenol sulfur (a polymeric monomer), 30mL of triethylamine (an acid-binding agent) and 150mg of basic zinc carbonate (an activating agent) into a mixed solvent of acetonitrile and water, carrying out ultrasonic treatment for 30min, then stirring for 12h, and carrying out centrifugal separation to obtain a material A2;

step S2: transferring the material A2 to a nickel boat, placing the nickel boat in a tube furnace, heating to 330 ℃ from room temperature for 60min in a nitrogen atmosphere with the flow rate of 100mL/min, keeping the temperature for 120min, heating to 700 ℃ at the heating rate of 3 ℃/min, keeping the temperature for 120min, and naturally cooling to room temperature to obtain a material B2;

step S3: and washing the material B2 with 2M hydrochloric acid solution for 2-3 times, and drying at 105 ℃ for 12h to obtain a target product, namely, the nitrogen-sulfur-phosphorus tri-doped carbon-based catalyst C2, wherein the nitrogen-sulfur-phosphorus tri-doped carbon-based electrode material C2 is used as a cathode catalyst of an electro-Fenton system to degrade 200mL of mixed dyes (methyl blue, methyl orange, methyl red and rhodamine B) with the concentration of 10mg/L, and the degradation efficiency is 87.9% after 150 min.

Example 3

Step S1: adding 121.8mg of hexachlorocyclotriphosphazene, 277.8mg of bisphenol sulfur (a polymeric monomer), 30mL of triethylamine (an acid-binding agent) and 150mg of basic zinc carbonate (an activating agent) into a mixed solvent of acetonitrile and water, carrying out ultrasonic treatment for 30min, then stirring for 12h, and carrying out centrifugal separation to obtain a material A3;

step S2: transferring the material A3 to a nickel boat, placing the nickel boat in a tube furnace, heating to 330 ℃ from room temperature for 60min in a nitrogen atmosphere with the flow rate of 100mL/min, keeping the temperature for 120min, heating to 800 ℃ at the heating rate of 3 ℃/min, keeping the temperature for 120min, and naturally cooling to room temperature to obtain a material B3;

step S3: washing the material B3 with 2M hydrochloric acid solution for 2-3 times, drying at 105 ℃ for 12h to obtain a target product, namely the nitrogen-phosphorus-sulfur triple-doped carbon-based catalyst C3, wherein the phosphorus-nitrogen-sulfur triple-doped carbon-based electrode material C3 is used for a supercapacitor under the acidic and alkaline systems at 1A g^-1The capacitance characteristic is as high as 184.8/160.4 Fg under the current density of (2)^-1Having an energy density of about 11.0Wh Kg^-1. Under alkaline conditions, the oxygen reduction potential is 7.1mV, which exceeds the oxygen reduction potential of Pt/C, and the stability and the methanol interference resistance are higherCan be used. Finally, 200mL of mixed dye (methyl blue, methyl orange, methyl red and rhodamine B) with the concentration of 10mg/L is degraded by using the cathode catalyst of the material for the electro-Fenton system, and the degradation efficiency is 98.0 percent after 150 min.

Example 4

Step S1: adding 121.8mg of hexachlorocyclotriphosphazene, 277.8mg of bisphenol sulfur (a polymeric monomer), 30mL of triethylamine (an acid-binding agent) and 150mg of basic zinc carbonate (an activating agent) into a mixed solvent of acetonitrile and water, carrying out ultrasonic treatment for 30min, then stirring for 12h, and carrying out centrifugal separation to obtain a material A4;

step S2: transferring the material A4 to a nickel boat, placing the nickel boat in a tube furnace, heating to 330 ℃ from room temperature for 60min in a nitrogen atmosphere with the flow rate of 100mL/min, keeping the temperature for 120min, heating to 900 ℃ at the heating rate of 5 ℃/min, keeping the temperature for 120min, and naturally cooling to room temperature to obtain a material B4;

step S3: and washing the material B4 with 2M hydrochloric acid solution for 2-3 times, and drying at 105 ℃ for 12h to obtain a target product nitrogen phosphorus three-doped carbon-based catalyst C4, wherein the nitrogen phosphorus sulfur three-doped carbon-based electrode material C4 is used as a cathode catalyst of an electro-Fenton system to degrade 200mL of mixed dyes (methyl blue, methyl orange, methyl red and rhodamine B) with the concentration of 10mg/L, and the degradation efficiency is 92.4% after 150 min.

The foregoing embodiments illustrate the principles, principal features and advantages of the invention, and it will be understood by those skilled in the art that the invention is not limited to the foregoing embodiments, which are merely illustrative of the principles of the invention, and that various changes and modifications may be made therein without departing from the scope of the principles of the invention.