阅读说明：本技术 一种沥青基氧还原电催化剂的制备方法 (Preparation method of asphalt-based oxygen reduction electrocatalyst ) 是由 李开喜 张娟 于 2021-01-25 设计创作，主要内容包括：本发明公开了一种沥青基氧还原电催化剂的制备方法,涉及新能源材料及电催化领域。其包含：将沥青作为碳源,首先预处理沥青,采用甲苯、吡啶和喹啉等三种溶剂将沥青逐级萃取,获得四种沥青族组分,并和中间相沥青混合；使用溶剂和浓硝酸、浓硫酸预处理,最后加入金属源、氮源研磨均匀,将混合均匀的原料装入管式炉中,采用高温炭化的方式充分反应,得到沥青基氧还原电催化剂。本发明制备方法简单,采用廉价的沥青取代卟啉、酞菁等价格昂贵的大环化合物,制备的氧还原电催化剂性能优良、成本低廉、容易量产；在燃料电池中具有广泛的应用前景。(The invention discloses a preparation method of an asphalt base oxygen reduction electrocatalyst, and relates to the field of new energy materials and electrocatalysis. Which comprises the following steps: taking asphalt as a carbon source, firstly pretreating the asphalt, extracting the asphalt step by adopting three solvents such as toluene, pyridine, quinoline and the like to obtain four asphalt group components, and mixing the components with mesophase asphalt; pretreating with a solvent, concentrated nitric acid and concentrated sulfuric acid, finally adding a metal source and a nitrogen source, grinding uniformly, putting the uniformly mixed raw materials into a tubular furnace, and fully reacting in a high-temperature carbonization mode to obtain the pitch-based oxygen reduction electrocatalyst. The preparation method is simple, cheap asphalt is adopted to replace expensive macrocyclic compounds such as porphyrin, phthalocyanine and the like, and the prepared oxygen reduction electrocatalyst has excellent performance, low cost and easy mass production; has wide application prospect in fuel cells.)

1. A preparation method of an asphalt-based oxygen reduction electrocatalyst is characterized by comprising the following steps:

the method comprises the following steps: firstly, pretreating an asphalt raw material:

weighing 2-5 g of dry asphalt with the particle size of 0.5-1.0 mm, adding 10-20 ml of toluene solvent, carrying out ultrasonic impregnation and suction filtration separation, removing the solvent from the solution of soluble components under reduced pressure, drying to obtain toluene soluble substances TS, separating the extracted insoluble components by adopting pyridine and quinoline, and marking the extracted components as toluene insoluble-pyridine soluble substances PS, pyridine insoluble-quinoline soluble substances QS and quinoline insoluble substances QI under the same treatment conditions;

then weighing each group of components of the asphalt extracted step by step, and mesophase asphalt and solvent with different softening points, slowly stirring, uniformly mixing, and standing to form suspension;

step two: then uniformly mixing the suspension obtained in the step one with an acid in the same volume, centrifuging, washing and drying to obtain modified asphalt as a carbon source; the acid is mixed with water in a volume ratio of 1: (0.5-9) mixing concentrated nitric acid and concentrated sulfuric acid;

step three: weighing a metal source and a nitrogen source, mixing the metal source and the nitrogen source with the carbon source obtained in the step two, and grinding the mixture into powder with uniform color;

step four: and (3) placing the product obtained in the third step into a tube furnace, heating to 350-550 ℃ at a heating rate of 2-10 ℃/min under a nitrogen atmosphere, keeping the temperature for 1-3 hours, heating to 600-900 ℃ at a heating rate of 3-9 ℃/min, carbonizing for 2-4 hours, naturally cooling to room temperature, and performing post-treatment to obtain the asphalt-based oxygen reduction electrocatalyst.

2. The method of preparing an asphalt-based oxygen-reducing electrocatalyst according to claim 1, wherein: in the first step, the asphalt is one of coal tar asphalt, medium temperature asphalt, high temperature asphalt, natural asphalt and petroleum asphalt; the solvent is one of ethanol, tetrahydrofuran, benzene, acetone, chloroform, n-octane and n-hexane.

3. The method of preparing an asphalt-based oxygen-reducing electrocatalyst according to claim 1, wherein: the dosage of the solvent accounts for 5-30% of the mass of the initial dry asphalt.

4. The method of preparing an asphalt-based oxygen-reducing electrocatalyst according to claim 1, wherein: the mass ratio of each group of components of the asphalt is TS: QS: QI is 1: (0.6-3): (0.3-5): (0.5 to 7).

5. The method of preparing an asphalt-based oxygen-reducing electrocatalyst according to claim 1, wherein: the mass ratio of the asphalt group component to the mesophase asphalt is TS, and the mass ratio of the mesophase asphalt is 1 (0.3-5); PS is (0.5-7) of mesophase pitch 1; QS is that the mesophase pitch is 1 (0.4-6); QI is that the mesophase pitch is 1 (0.7-5); the softening point of the mesophase pitch is 280-350 ℃.

6. The method of preparing an asphalt-based oxygen-reducing electrocatalyst according to claim 1, wherein: the metal source is an organic compound containing a transition metal element, and comprises: ferrocene, ferrocenecarboxylic acid, cobalt naphthenate, cobalt acetylacetonate, bis (cyclopentadienyl) nickel, nickel acetylacetonate, zinc bis (2, 4-pentanedionate), zinc dimethyldithiocarbamate, copper phenolcyanine and copper 8-hydroxyquinoline; the nitrogen source is as follows: cyanamide, melamine, ethylenediamine, adenine, polyacrylonitrile, polypyrrole, polyaniline, polydopamine, urea, thiourea and C₃N₄One kind of (1).

7. The method of preparing an asphalt-based oxygen-reducing electrocatalyst according to claim 1, wherein: in the third step, the metal source: the mass ratio of the nitrogen source is 1: (0.25 to 2.5); carbon source: the mass ratio of the metal source is 1: (0.4-6).

8. The method of preparing an asphalt-based oxygen-reducing electrocatalyst according to claim 7, wherein: metal source: the nitrogen source is 1: (0.5-2).

9. The method of preparing an asphalt-based oxygen-reducing electrocatalyst according to claim 1, wherein: the post-treatment comprises the following steps: placing the calcined product at 2 mol.L^-1Acidifying in the dilute hydrochloric acid solution for 7-24 hours, centrifuging the suspension obtained after reaction, washing the suspension with deionized water until the pH value of the filtrate is 6.8-7.2, and drying the obtained product at 60-80 ℃ for 7-12 hours to obtain the product which is powdery and can be directly used without crushing and pulverization.

10. An asphalt-based oxygen-reducing electrocatalyst prepared by the process of any one of claims 1 to 9, wherein: uniformly dispersing the prepared asphalt-based oxygen reduction electrocatalyst into deionized water and a Nafion alcohol solution, and coating the mixed solution on the surface of a glassy carbon electrode after ultrasonic treatment to prepare a working electrode; the oxidation-reduction peak potential of the obtained asphalt-based oxygen-reduction electrocatalyst is 0.86-0.90V, and the asphalt-based oxygen-reduction electrocatalyst has excellent ORR performance.

Technical Field

The invention relates to a preparation method of an asphalt base oxygen reduction electrocatalyst, belonging to the field of new energy materials and electrocatalysis.

Background

The non-renewable nature of fossil energy and the environmental problems associated with its use are two major challenges facing humans. The development of new energy sources and new energy technology which are environmentally friendly and renewable has become a research hotspot in the world today. The fuel cell is an energy conversion mode for directly converting chemical energy into electric energy, and has the advantages of environmental friendliness, high energy density, high conversion efficiency and the like. The main factor restricting the technical development of the fuel cell is the low efficiency of the cathode oxygen reduction reaction; the traditional cathode catalyst Pt has the problems of poor activity and durability, scarce resources and the like, and the large-scale application of the fuel cell is limited to a great extent. Therefore, the development of a cathode catalyst with low cost, abundant storage and excellent performance becomes the key to the development of fuel cells.

Since Jasinski (Jasinski R, A new fuel cell catalyst, Nature, 1964,201: 1212-1213) discovered that cobalt phthalocyanine has considerable ORR catalytic activity in alkaline medium in 1964; opens up the research of transition metal-nitrogen-carbon (M-N-C) catalyst. For a long time, the research on M-N-C catalysts aims to solve the problem by exploring new metal elements; designing a multi-atom metal center, optimizing a coordination structure and promoting the activity of a single active site; the influence of carbon structure on catalytic performance is of less concern. Chinese patent CN 106450354B discloses a hydrothermal synthesis method of a nitrogen-doped graphene-supported cobalt-oxygen reduction reaction electrocatalyst, which comprises the steps of firstly, blending and heating urea and Graphene Oxide (GO) to perform N-doping modification, then loading a cobalt compound on the surface of the N-doped GO under a hydrothermal condition, and reducing by hydrazine hydrate under the hydrothermal condition to obtain the nitrogen-doped graphene-supported cobalt composite material. Twice hydrothermal treatment, the experimental conditions are harsh and complex; the carbon source GO is complex in synthesis process and not beneficial to industrialization. Chinese patent CN 109950557B uses porous nitrogen-doped carbon as a carrier, and Fe is dispersed on the carrier in a single atom form and coordinated with nitrogen in the carrier to form an active site. The iron source and the nitrogen source of the raw materials are both organic complexes, so the cost of synthesizing the catalyst is high; the Fe monoatomic atoms adsorbed on the porous carbon inevitably form agglomeration in the pyrolysis process to cause reduction of the catalytic performance. Chinese patent CN 110690458A made of SiO₂Using melamine as carbon precursor and nitrogen source, using ferric chloride as iron source, adopting dipping method, controlled pyrolysis method and chemical etchingThe method is combined to prepare the bamboo-shaped nitrogen-doped carbon nano tube electrocatalyst. SiO is used in the synthesis process₂The template is removed by HF, which causes environmental pollution. In a word, the carbon source selected in the catalyst is indirectly synthesized, and the raw material is not directly used; the choice of metal source also has limitations, most using Fe, Co, etc. However, the research of synthesizing M-N-C catalyst from molecular level by directly pretreating asphalt with asphalt as carbon source has not been reported.

Disclosure of Invention

Aiming at the problems of complex carbon source synthesis process, matching of a carbon carrier and metal and the like at present, the invention provides an asphalt-based oxygen reduction electrocatalyst synthesized by using cheap asphalt as a raw material and a preparation method thereof.

The invention provides a preparation method of an asphalt base oxygen reduction electrocatalyst, which comprises the following steps:

the method comprises the following steps: firstly, pretreating an asphalt raw material:

weighing 2-5 g of dry asphalt with the particle size of 0.5-1.0 mm, adding 10-20 ml of toluene solvent, carrying out ultrasonic impregnation and suction filtration separation, removing the solvent from the solution of soluble components under reduced pressure, drying to obtain toluene soluble substances (TS), separating the extracted insoluble components by adopting pyridine and quinoline, and marking the extracted components as toluene insoluble-pyridine soluble substances (PS), pyridine insoluble-quinoline soluble substances (QS) and quinoline insoluble substances (QI) under the same treatment conditions;

then weighing the gradually extracted proper amount of asphalt components, mesophase asphalt with different softening points and proper amount of solvent, slowly stirring, uniformly mixing, and standing to form suspension;

step two: then, mixing the suspension obtained in the first step with a solvent in a volume ratio of 1: (0.5-9) after uniformly mixing the concentrated nitric acid and the concentrated sulfuric acid in equal volume, centrifuging, washing and drying to obtain modified asphalt as a carbon source;

step three: weighing a metal source and a nitrogen source, mixing the metal source and the nitrogen source with the carbon source obtained in the step two, and grinding the mixture into powder with uniform color;

step four: and (3) placing the product obtained in the third step into a tube furnace, heating to 350-550 ℃ at a heating rate of 2-10 ℃/min under a nitrogen atmosphere, keeping the temperature for 1-3 hours, heating to 600-900 ℃ at a heating rate of 3-9 ℃/min, carbonizing for 2-4 hours, naturally cooling to room temperature, and performing post-treatment to obtain the asphalt-based oxygen reduction electrocatalyst.

In the preparation method, in the first step, the asphalt is one of coal tar asphalt, medium temperature asphalt, high temperature asphalt, natural asphalt and petroleum asphalt;

in the preparation method, in the first step, the solvent is one of ethanol, tetrahydrofuran, benzene, acetone, chloroform, n-octane and n-hexane;

the dosage of the solvent accounts for 5-30% of the mass of the initial dry asphalt raw material.

According to the preparation method, the mass ratio of the asphalt group component to the mesophase asphalt is TS, and the mass ratio of the mesophase asphalt is 1 (0.3-5); PS is (0.5-7) of mesophase pitch 1; QS is that the mesophase pitch is 1 (0.4-6); QI is that the mesophase pitch is 1 (0.7-5); the softening point of the mesophase pitch is 280-350 ℃.

According to the preparation method, the mass ratio of the components of each group of the asphalt is TS: QS: QI is 1: (0.6-3): (0.3-5): (0.5 to 7).

In the above preparation method, the metal source is an organic compound containing a transition metal element, and the method includes: ferrocene, ferrocenecarboxylic acid, cobalt naphthenate, cobalt acetylacetonate, bis (cyclopentadienyl) nickel, nickel acetylacetonate, zinc bis (2, 4-pentanedionate), zinc dimethyldithiocarbamate, copper phenolcyanine and copper 8-hydroxyquinoline;

the nitrogen source is as follows: cyanamide, melamine, ethylenediamine, adenine, polyacrylonitrile, polypyrrole, polyaniline, polydopamine, urea, thiourea and C₃N₄One kind of (1).

In the preparation method, in the third step, the metal source: the mass ratio of the nitrogen source is 1: (0.25 to 2.5); carbon source: the mass ratio of the metal source is 1: (0.4-6). Preferably, the metal source: the nitrogen source is 1: (0.5-2).

In the preparation method, the post-treatment comprises the following steps: placing the calcined product at 2 mol.L^-1Is acidified in dilute hydrochloric acid solution of 7 to 24Centrifuging the suspension obtained after the reaction, washing the suspension with deionized water until the pH value of the filtrate is 6.8-7.2, and drying the obtained product at 60-80 ℃ for 7-12 hours to obtain a powder product which can be directly used without crushing and powdering.

The catalytic performance of the pitch-based oxygen reduction electrocatalyst prepared by the present invention was evaluated by cyclic voltammetry curves (CV curves). The prepared pitch-based oxygen reduction electrocatalyst is uniformly dispersed into deionized water and Nafion (Dupont, 5 wt.%) alcohol solution, and the suspension is coated on the surface of a glassy carbon electrode to prepare a working electrode. Also for comparison, a commercial Pt/C (20%, JM) catalyst was prepared in the same manner and tested under the same conditions.

The ORR activity of the material was tested using the LSV and CV methods. The electrochemical performances of the asphalt-based oxygen reduction electrocatalyst and the commercially available Pt/C catalyst are respectively tested by adopting a three-electrode system, and the electrochemical performances are measured at 0.1 mol.L^-1 KOH solution is used as electrolyte, a rotating disk electrode coated with catalyst is used as a working electrode, and a platinum sheet (1.92 cm)²) As a counter electrode, Hg/HgO was used as a reference electrode. Before testing, respectively open O₂Or Ar, making O in the electrolyte₂Or Ar reaches saturation. For the ORR test, LSV curves were obtained at different rotational speeds; the performance was measured by the continuous CV method.

The oxidation-reduction peak potential of the obtained asphalt-based oxygen-reduction electrocatalyst is 0.86-0.90V, and the asphalt-based oxygen-reduction electrocatalyst has excellent ORR performance.

The invention has the beneficial effects that:

(1) the asphalt-based oxygen reduction electrocatalyst has excellent catalytic performance. The low-added-value raw material asphalt is modified and converted into the high-added-value electrocatalyst, so that great potential is provided for the application of the electrocatalyst in energy conversion (hydrogen production by water electrolysis) and energy storage technologies (fuel cells, metal air cells, lithium sulfur cells, super capacitors and the like);

(2) the catalytic activity of the asphalt-based oxygen reduction electrocatalyst is equivalent to that of a platinum-based catalyst, so that the cost of the catalyst is obviously reduced;

(3) the pitch-based oxygen reduction electrocatalyst adopts one-step carbonization, replaces long-time hydrothermal, carbonization and activation processes, saves manpower, material resources and time for preparing the catalyst, has simple preparation process, and is suitable for industrialization;

(4) the pitch-based oxygen reduction electrocatalyst has uniform appearance, cheap and easily obtained raw material pitch and high yield.

Drawings

FIG. 1 shows the results of the oxidation of the pitch-based oxygen-reducing electrocatalyst at O in example 1₂And 0.1 mol. L saturated with Ar^-1 CV plot in KOH solution;

FIG. 2 is a scanning electron microscope image of the pitch-based oxygen-reducing electrocatalyst in example 1;

FIG. 3 shows the results of the oxidation of the pitch-based oxygen-reducing electrocatalyst in example 1 at O₂And 0.1 mol. L saturated with Ar^-1 LSV profile at different rotation speeds in KOH solution.

Detailed Description

The present invention is further illustrated by, but is not limited to, the following examples.

Example 1:

weighing 2 g of medium temperature asphalt with the particle size of 0.5 mm, adding 10ml of toluene solvent, carrying out ultrasonic impregnation, suction filtration and separation, removing the solvent from the solution of soluble components under reduced pressure, and drying to obtain toluene soluble substance (TS). Then weighing 1.5 g TS, 0.75 g mesophase pitch with the softening point of 290 ℃ and 10ml ethanol, slowly stirring and uniformly mixing; the ratio of the latter to the volume is 2: 1, uniformly mixing concentrated nitric acid and concentrated sulfuric acid, centrifuging, washing, drying, mixing with 3.2 g of ferrocene and 1.6 g of cyanamide, and grinding into powder with uniform color; placing the mixture into a tubular furnace, heating the mixture to 350 ℃ at the heating rate of 2 ℃/min under the nitrogen atmosphere, keeping the temperature for 1 hour, heating the mixture to 600 ℃ at the heating rate of 3 ℃/min, carbonizing the mixture for 2 hours, naturally cooling the carbonized mixture to room temperature, and performing post-treatment to obtain the asphalt-based oxygen reduction electrocatalyst.

The specific detection process is as follows: weighing 5mg of the pitch-based oxygen reduction electrocatalyst, adding the 5mg of the pitch-based oxygen reduction electrocatalyst into a mixed solution of 1ml of an aqueous solution of isopropanol (volume ratio of isopropanol to deionized water = 1: 1) and 10 μ L of Nafion perfluorosulfonate solution (Dupont, 5 wt.%), performing ultrasonic treatment for 1h, and then dropping 10 μ L of 0.192 cm in area²Obtaining a working electrode on the glassy carbon electrode; testing ORR activity with electrochemical workstation and electrolyte of O₂Saturated 0.1 mol. L^-1 KOH, scan rate 10mV s^-1。

FIG. 1 shows the results of the oxidation of the pitch-based oxygen-reducing electrocatalyst at O in example 1₂And 0.1 mol. L saturated with Ar^-1 CV plot in KOH solution; FIG. 2 is a scanning electron microscope image of the pitch-based oxygen-reducing electrocatalyst in example 1; FIG. 3 shows the results of the oxidation of the pitch-based oxygen-reducing electrocatalyst in example 1 at O₂And 0.1 mol. L saturated with Ar^-1 LSV profile at different rotation speeds in KOH solution.

The oxidation-reduction peak potential of the obtained electrocatalyst is 0.86V, and the ORR electrocatalysis performance is superior to Pt/C; and has better stability and methanol resistance, and also has excellent cycle stability in fuel cells.

Example two

Weighing 2.5g of high temperature asphalt with the particle size of 0.7 mm, adding 13 ml of toluene solvent, carrying out ultrasonic impregnation and suction filtration separation to obtain toluene insoluble substances (TI), continuously separating the TI insoluble substances by pyridine and quinoline respectively, and obtaining corresponding quinoline insoluble substances (QI) under the same treatment conditions. Then weighing 2 g of QI, 1.4 g of mesophase pitch with the softening point of 300 ℃ and 15ml of n-hexane, slowly stirring and uniformly mixing; the ratio of the latter to the volume is 1: 4, uniformly mixing the concentrated nitric acid and the concentrated sulfuric acid, centrifuging, washing and drying, then mixing with 1.2 g of bis (2, 4-glutaric acid) zinc and 3 g of polypyrrole, and grinding into powder with uniform color; placing the mixture into a tubular furnace, heating the mixture to 400 ℃ at the heating rate of 4 ℃/min under the nitrogen atmosphere, keeping the temperature for 2 hours, heating the mixture to 700 ℃ at the heating rate of 4 ℃/min, carbonizing the mixture for 3 hours, naturally cooling the carbonized mixture to room temperature, and performing post-treatment to obtain the asphalt-based oxygen reduction electrocatalyst.

The specific detection procedure was the same as in example 1.

The oxidation-reduction peak potential of the obtained electrocatalyst is 0.88V, and the ORR electrocatalysis performance is superior to Pt/C; and has better stability and methanol resistance, and also has excellent cycle stability in fuel cells.

EXAMPLE III

Weighing 3 g of natural asphalt with the particle size of 0.5 mm, adding 12 ml of toluene solvent, carrying out ultrasonic impregnation and suction filtration separation to obtain toluene insoluble substances (TI), continuously separating the toluene insoluble substances (TI) by adopting pyridine and quinoline, and obtaining corresponding toluene insoluble-pyridine soluble substances (PS) under the same treatment conditions. Then weighing 1.5 g of PS, 3.5g of mesophase pitch with the softening point of 330 ℃ and 20ml of tetrahydrofuran, slowly stirring and uniformly mixing; the ratio of the latter to the volume is 1: 3, uniformly mixing the concentrated nitric acid and the concentrated sulfuric acid, centrifuging, washing, drying, mixing with 2.5g of ferrocenecarboxylic acid and 3 g of melamine, and grinding into powder with uniform color; placing the mixture into a tubular furnace, heating the mixture to 400 ℃ at the heating rate of 3 ℃/min under the nitrogen atmosphere, keeping the temperature for 2 hours, heating the mixture to 700 ℃ at the heating rate of 4 ℃/min, carbonizing the mixture for 2 hours, naturally cooling the carbonized mixture to room temperature, and performing post-treatment to obtain the asphalt-based oxygen reduction electrocatalyst.

The specific detection procedure was the same as in example 1.

The oxidation-reduction peak potential of the obtained electrocatalyst is 0.86V, and the ORR electrocatalysis performance is superior to Pt/C; and has better stability and methanol resistance, and also has excellent cycle stability in fuel cells.

Example four

Weighing 5g of coal tar pitch with the particle size of 0.6mm, adding 10ml of toluene solvent, carrying out ultrasonic impregnation and suction filtration separation, removing the solvent from the solution of soluble components under reduced pressure, and drying to obtain toluene soluble substance (TS). Then weighing 2.6 g of TS, 1.8g of mesophase pitch with the softening point of 320 ℃ and 15ml of acetone, mixing and slowly stirring, and uniformly mixing; the ratio of the latter to the volume is 1: 9, uniformly mixing concentrated nitric acid and concentrated sulfuric acid, centrifuging, washing, drying, mixing with 1.5 g of nickel acetylacetonate and 2.5g of cyanamide, and grinding into powder with uniform color; placing the mixture into a tubular furnace, heating the mixture to 500 ℃ at a heating rate of 5 ℃/min under the nitrogen atmosphere, keeping the temperature for 3 hours, heating the mixture to 800 ℃ at a heating rate of 8 ℃/min, carbonizing the mixture for 2 hours, naturally cooling the carbonized mixture to room temperature, and performing post-treatment to obtain the asphalt-based oxygen reduction electrocatalyst.

The specific detection procedure was the same as in example 1.

The oxidation-reduction peak potential of the obtained electrocatalyst is 0.90V, and the ORR electrocatalysis performance is superior to Pt/C; and has better stability and methanol resistance, and also has excellent cycle stability in fuel cells.

EXAMPLE five

Weighing 4.4g of medium temperature pitch with the particle size of 0.5 mm, adding 14 ml of toluene solvent, carrying out ultrasonic impregnation and suction filtration separation to obtain toluene insoluble substances (TI), continuously separating the toluene insoluble substances (TI) by adopting pyridine and quinoline respectively, and obtaining corresponding pyridine insoluble-quinoline soluble substances (QS) under the same treatment conditions. Then weighing 2 g of QS, 2.4 g of mesophase pitch with the softening point of 350 ℃ and 25ml of n-hexane, slowly stirring and uniformly mixing; the ratio of the latter to the volume is 1: 4, uniformly mixing the concentrated nitric acid and the concentrated sulfuric acid, centrifuging, washing, drying, mixing with 1.2 g of cobalt naphthenate and 1.5 g of ethylenediamine, and grinding into powder with uniform color; placing the mixture into a tubular furnace, heating the mixture to 450 ℃ at a heating rate of 4 ℃/min under the nitrogen atmosphere, keeping the temperature for 3 hours, heating the mixture to 800 ℃ at a heating rate of 5 ℃/min, carbonizing the mixture for 2 hours, naturally cooling the carbonized mixture to room temperature, and performing post-treatment to obtain the asphalt-based oxygen reduction electrocatalyst.

The specific detection procedure was the same as in example 1.

The oxidation-reduction peak potential of the obtained electrocatalyst is 0.88V, and the ORR electrocatalysis performance is superior to Pt/C; and has better stability and methanol resistance, and also has excellent cycle stability in fuel cells.

EXAMPLE six

Weighing 2.6 g of coal tar pitch with the particle size of 0.6mm, adding 16 ml of toluene solvent, carrying out ultrasonic impregnation and suction filtration separation to obtain toluene insoluble matter (TI), continuously separating the toluene insoluble matter (TI) by adopting pyridine and quinoline, and obtaining corresponding toluene insoluble-pyridine soluble matter (PS) under the same treatment condition. Then weighing 1.2 g of PS, 2.7 g of mesophase pitch with the softening point of 280 ℃ and 10ml of benzene, slowly stirring and uniformly mixing; the ratio of the latter to the volume is 2: 13, uniformly mixing concentrated nitric acid and concentrated sulfuric acid, centrifuging, washing, drying, mixing with 3.6 g of cobalt naphthenate and 2.5g of polypropylene cyanide, and grinding into powder with uniform color; placing the mixture into a tubular furnace, heating the mixture to 550 ℃ at the heating rate of 3 ℃/min under the nitrogen atmosphere, keeping the temperature for 3 hours, heating the mixture to 900 ℃ at the heating rate of 6 ℃/min, carbonizing the mixture for 3 hours, naturally cooling the carbonized mixture to room temperature, and performing post-treatment to obtain the asphalt-based oxygen reduction electrocatalyst.

The specific detection procedure was the same as in example 1.

The oxidation-reduction peak potential of the obtained electrocatalyst is 0.87V, and the ORR electrocatalysis performance is superior to Pt/C; and has better stability and methanol resistance, and also has excellent cycle stability in fuel cells.

EXAMPLE seven

Weighing 2.9 g of high temperature asphalt with the particle size of 0.9mm, adding 18 ml of toluene solvent, carrying out ultrasonic impregnation and suction filtration separation to obtain toluene insoluble substances (TI), continuously separating the toluene insoluble substances (TI) by using pyridine and quinoline respectively, and obtaining corresponding pyridine insoluble-quinoline soluble substances (QS) under the same treatment conditions. Then weighing 1 g QS, 4g of mesophase pitch with the softening point of 340 ℃ and 15ml of chloroform, slowly stirring and uniformly mixing; the ratio of the latter to the volume is 1: 5, uniformly mixing concentrated nitric acid and concentrated sulfuric acid, centrifuging, washing, drying, mixing with 1.5 g of cobalt acetylacetonate and 0.5 g of adenine, and grinding into powder with uniform color; placing the mixture into a tubular furnace, heating the mixture to 500 ℃ at the heating rate of 6 ℃/min under the nitrogen atmosphere, keeping the temperature for 1 hour, heating the mixture to 800 ℃ at the heating rate of 5 ℃/min, carbonizing the mixture for 2 hours, naturally cooling the carbonized mixture to room temperature, and performing post-treatment to obtain the asphalt-based oxygen reduction electrocatalyst.

The specific detection procedure was the same as in example 1.

The oxidation-reduction peak potential of the obtained electrocatalyst is 0.86V, and the ORR electrocatalysis performance is superior to Pt/C; and has better stability and methanol resistance, and also has excellent cycle stability in fuel cells.

Example eight

Weighing 3.6 g petroleum asphalt with particle size of 0.5 mm, adding 20ml toluene solvent, ultrasonic soaking, vacuum filtering, separating to obtain toluene insoluble substance (TI), separating with pyridine and quinoline, and processing under the same conditions to obtain corresponding toluene insoluble-pyridine soluble substance (PS). Then weighing 1.7 g of PS, 1 g of mesophase pitch with the softening point of 290 ℃ and 15ml of acetone, slowly stirring and uniformly mixing; the ratio of the latter to the volume is 2: 11, uniformly mixing concentrated nitric acid and concentrated sulfuric acid, centrifuging, washing, drying, mixing with 2.1 g of zinc dimethyldithiocarbamate and 0.7 g of ethylenediamine, and grinding into powder with uniform color; placing the mixture into a tubular furnace, heating the mixture to 450 ℃ at the heating rate of 6 ℃/min under the nitrogen atmosphere, keeping the temperature for 2 hours, heating the mixture to 900 ℃ at the heating rate of 6 ℃/min, carbonizing the mixture for 2 hours, naturally cooling the carbonized mixture to room temperature, and performing post-treatment to obtain the asphalt-based oxygen reduction electrocatalyst.

The specific detection procedure was the same as in example 1.

The oxidation-reduction peak potential of the obtained electrocatalyst is 0.89V, and the ORR electrocatalytic performance is superior to that of Pt/C; and has better stability and methanol resistance, and also has excellent cycle stability in fuel cells.

Example nine

Weighing 4g of medium temperature pitch with the particle size of 0.8 mm, adding 13 ml of toluene solvent, carrying out ultrasonic impregnation and suction filtration separation to obtain toluene insoluble substances (TI), continuously separating the TI by adopting pyridine and quinoline, and obtaining corresponding quinoline insoluble substances (QI) under the same treatment conditions. Then weighing 1.6 g of QI, 1.4 g of mesophase pitch with the softening point of 320 ℃ and 20ml of n-hexane, slowly stirring and uniformly mixing; the ratio of the latter to the volume is 1: 6, uniformly mixing the concentrated nitric acid and the concentrated sulfuric acid, centrifuging, washing and drying, then mixing with 1.4 g of bis (cyclopentadienyl) nickel and 2.6 g of polyacrylonitrile, and grinding into powder with uniform color; placing the mixture into a tubular furnace, heating the mixture to 500 ℃ at the heating rate of 3 ℃/min under the nitrogen atmosphere, keeping the temperature for 1 hour, heating the mixture to 900 ℃ at the heating rate of 9 ℃/min, carbonizing the mixture for 2 hours, naturally cooling the carbonized mixture to room temperature, and performing post-treatment to obtain the asphalt-based oxygen reduction electrocatalyst.

The specific detection procedure was the same as in example 1.

The oxidation-reduction peak potential of the obtained electrocatalyst is 0.87V, and the ORR electrocatalysis performance is superior to Pt/C; and has better stability and methanol resistance, and also has excellent cycle stability in fuel cells.

Example ten

Weighing 3.8 g of natural asphalt with the particle size of 1mm, adding 15ml of toluene solvent, carrying out ultrasonic impregnation, suction filtration and separation, removing the solvent from the solution of soluble components under reduced pressure, and drying to obtain the toluene soluble substance (TS). Then 0.8 g TS, 1.5 g mesophase pitch with the softening point of 330 ℃ and 15ml acetone are weighed, slowly stirred and evenly mixed; the ratio of the latter to the volume is 2: 9, uniformly mixing concentrated nitric acid and concentrated sulfuric acid, centrifuging, washing, drying, mixing with 1.3 g of nickel acetylacetonate and 2.6 g of melamine, and grinding into powder with uniform color; placing the mixture into a tubular furnace, heating the mixture to 500 ℃ at a heating rate of 5 ℃/min under the nitrogen atmosphere, keeping the temperature for 3 hours, heating the mixture to 900 ℃ at a heating rate of 5 ℃/min, carbonizing the mixture for 3 hours, naturally cooling the carbonized mixture to room temperature, and performing post-treatment to obtain the asphalt-based oxygen reduction electrocatalyst.

The specific detection procedure was the same as in example 1.

The oxidation-reduction peak potential of the obtained electrocatalyst is 0.88V, and the ORR electrocatalysis performance is superior to Pt/C; and has better stability and methanol resistance, and also has excellent cycle stability in fuel cells.

EXAMPLE eleven

Weighing 2.8 g of high-temperature asphalt with the particle size of 0.5 mm, adding 17 ml of toluene solvent, carrying out ultrasonic impregnation and suction filtration separation to obtain toluene insoluble substances (TI), continuously separating the toluene insoluble substances (TI) by using pyridine and quinoline respectively, and obtaining corresponding pyridine insoluble-quinoline soluble substances (QS) under the same treatment conditions. Then weighing 1.5 g of QS, 2.7 g of mesophase pitch with the softening point of 290 ℃ and 10ml of tetrahydrofuran, slowly stirring and uniformly mixing; the ratio of the latter to the volume is 1: 7, uniformly mixing concentrated nitric acid and concentrated sulfuric acid, centrifuging, washing, drying, mixing with 0.7 g of copper phenolate and 1.8g of polypyrrole, and grinding into powder with uniform color; placing the mixture into a tubular furnace, heating the mixture to 500 ℃ at a heating rate of 4 ℃/min under the nitrogen atmosphere, keeping the temperature for 3 hours, heating the mixture to 800 ℃ at a heating rate of 8 ℃/min, carbonizing the mixture for 3 hours, naturally cooling the carbonized mixture to room temperature, and performing post-treatment to obtain the asphalt-based oxygen reduction electrocatalyst.

The specific detection procedure was the same as in example 1.

The oxidation-reduction peak potential of the obtained electrocatalyst is 0.90V, and the ORR electrocatalysis performance is superior to Pt/C; and has better stability and methanol resistance, and also has excellent cycle stability in fuel cells.

Example twelve

Weighing 2.2 g of coal tar pitch with the particle size of 0.7 mm, adding 19 ml of toluene solvent, carrying out ultrasonic impregnation and suction filtration separation to obtain toluene insoluble substances (TI), continuously separating the TI insoluble substances by pyridine and quinoline respectively, and obtaining corresponding quinoline insoluble substances (QI) under the same treatment conditions. Then weighing 1.5 g of QI, 3.2 g of mesophase pitch with the softening point of 330 ℃ and 20ml of benzene, slowly stirring and uniformly mixing; the ratio of the latter to the volume is 2: 7, evenly mixing the concentrated nitric acid and the concentrated sulfuric acid, centrifuging, washing and drying the mixture, and then weighing 2.4 g of bis (2, 4-pentanedionato) zinc and 3 g C₃N₄Mixing and grinding into powder with uniform color; placing the mixture into a tubular furnace, heating the mixture to 500 ℃ at a heating rate of 5 ℃/min under the nitrogen atmosphere, keeping the temperature for 3 hours, heating the mixture to 900 ℃ at a heating rate of 6 ℃/min, carbonizing the mixture for 4 hours, naturally cooling the carbonized mixture to room temperature, and performing post-treatment to obtain the asphalt-based oxygen reduction electrocatalyst.

The specific detection procedure was the same as in example 1.

The oxidation-reduction peak potential of the obtained electrocatalyst is 0.89V, and the ORR electrocatalytic performance is superior to that of Pt/C; and has better stability and methanol resistance, and also has excellent cycle stability in fuel cells.

EXAMPLE thirteen

Weighing 1.8g of natural asphalt with the particle size of 0.6mm, adding 20ml of toluene solvent, carrying out ultrasonic impregnation, suction filtration and separation, removing the solvent from the solution of soluble components under reduced pressure, and drying to obtain toluene soluble substances (TS). Then 0.8 g TS, 2.6 g mesophase pitch with the softening point of 310 ℃ and 25ml n-octane are weighed and slowly stirred and evenly mixed; the ratio of the latter to the volume is 1: 8, uniformly mixing concentrated nitric acid and concentrated sulfuric acid, centrifuging, washing, drying, mixing with 1.5 g of 8-hydroxyquinoline copper and 0.8 g of polyaniline, and grinding into powder with uniform color; placing the mixture into a tubular furnace, heating the mixture to 400 ℃ at the heating rate of 5 ℃/min under the nitrogen atmosphere, keeping the temperature for 1.5 hours, heating the mixture to 800 ℃ at the heating rate of 6 ℃/min, carbonizing the mixture for 2 hours, naturally cooling the carbonized mixture to room temperature, and performing post-treatment to obtain the asphalt-based oxygen reduction electrocatalyst.

The specific detection procedure was the same as in example 1.

The oxidation-reduction peak potential of the obtained electrocatalyst is 0.87V, and the ORR electrocatalysis performance is superior to Pt/C; and has better stability and methanol resistance, and also has excellent cycle stability in fuel cells.

Example fourteen

Weighing 2.8 g of high temperature asphalt with the particle size of 0.5 mm, adding 12 ml of toluene solvent, carrying out ultrasonic impregnation and suction filtration separation to obtain toluene insoluble substances (TI), continuously separating the TI insoluble substances by pyridine and quinoline respectively, and obtaining corresponding quinoline insoluble substances (QI) under the same treatment conditions. Then weighing 1.6 g of QI, 3.4 g of mesophase pitch with the softening point of 340 ℃ and 10ml of chloroform, slowly stirring and uniformly mixing; the ratio of the latter to the volume is 2: 5, uniformly mixing concentrated nitric acid and concentrated sulfuric acid, centrifuging, washing, drying, mixing with 3.2 g of zinc dimethyldithiocarbamate and 1.8g of thiourea, and grinding into powder with uniform color; placing the mixture into a tubular furnace, heating the mixture to 400 ℃ at a heating rate of 4 ℃/min under the nitrogen atmosphere, keeping the temperature for 2 hours, heating the mixture to 700 ℃ at a heating rate of 5 ℃/min, carbonizing the mixture for 3 hours, naturally cooling the carbonized mixture to room temperature, and performing post-treatment to obtain the asphalt-based oxygen reduction electrocatalyst.

The specific detection procedure was the same as in example 1.

The oxidation-reduction peak potential of the obtained electrocatalyst is 0.88V, and the ORR electrocatalysis performance is superior to Pt/C; and has better stability and methanol resistance, and also has excellent cycle stability in fuel cells.

Example fifteen

Weighing 3.5g of medium temperature pitch with the particle size of 1mm, adding 18 ml of toluene solvent, carrying out ultrasonic impregnation and suction filtration separation to obtain toluene insoluble substances (TI), continuously separating the toluene insoluble substances (TI) by adopting pyridine and quinoline, and obtaining corresponding toluene insoluble-pyridine soluble substances (PS) under the same treatment conditions. Then weighing 1.8g of PS, 3.2 g of mesophase pitch with the softening point of 330 ℃ and 15ml of ethanol, slowly stirring and uniformly mixing; the ratio of the latter to the volume is 1: 9, uniformly mixing concentrated nitric acid and concentrated sulfuric acid, centrifuging, washing, drying, mixing with 3.5g of 8-hydroxyquinoline copper and 1.7 g of polydopamine, and grinding into powder with uniform color; placing the mixture into a tubular furnace, heating the mixture to 500 ℃ at a heating rate of 4 ℃/min under the nitrogen atmosphere, keeping the temperature for 2 hours, heating the mixture to 800 ℃ at a heating rate of 5 ℃/min, carbonizing the mixture for 3 hours, naturally cooling the carbonized mixture to room temperature, and performing post-treatment to obtain the asphalt-based oxygen reduction electrocatalyst.

The specific detection procedure was the same as in example 1.

The oxidation-reduction peak potential of the obtained electrocatalyst is 0.86V, and the ORR electrocatalysis performance is superior to Pt/C; and has better stability and methanol resistance, and also has excellent cycle stability in fuel cells.

Example sixteen

Weighing 2.5g of petroleum asphalt with the particle size of 0.8 mm, adding 16 ml of toluene solvent, carrying out ultrasonic impregnation, suction filtration and separation, removing the solvent from the solution of soluble components under reduced pressure, and drying to obtain toluene soluble substance (TS). Then weighing 1.8g of TS, 1.2 g of mesophase pitch with the softening point of 350 ℃ and 20ml of acetone, slowly stirring and uniformly mixing; the ratio of the latter to the volume is 2: 3, uniformly mixing the concentrated nitric acid and the concentrated sulfuric acid, centrifuging, washing and drying, mixing with 2.3 g of copper phenolate and 0.8 g of urea, and grinding into powder with uniform color; placing the mixture into a tubular furnace, heating the mixture to 350 ℃ at a heating rate of 2 ℃/min under the nitrogen atmosphere, keeping the temperature for 2 hours, heating the mixture to 600 ℃ at a heating rate of 3 ℃/min, carbonizing the mixture for 2 hours, naturally cooling the carbonized mixture to room temperature, and performing post-treatment to obtain the asphalt-based oxygen reduction electrocatalyst.

The specific detection procedure was the same as in example 1.

The oxidation-reduction peak potential of the obtained electrocatalyst is 0.87V, and the ORR electrocatalysis performance is superior to Pt/C; and has better stability and methanol resistance, and also has excellent cycle stability in fuel cells.