阅读说明：本技术 一种储能碳材料及其制备方法和应用 (Energy storage carbon material and preparation method and application thereof ) 是由 李治 雷杰 李康 王韬翔 韩海波 于 2021-08-06 设计创作，主要内容包括：本发明公开了一种储能碳材料及其制备方法和应用,涉及重油制备碳材料的技术领域,所述储能碳材料为层状结构,层厚度为3～10nm,层间距为0.3～0.5nm,粒径大于15μm,与传统的多孔超级电容器用碳材料相比,层状结构碳材料比表面积得到了大幅提高,同时扩大与电解液的接触范围,提高浸润性；另一方面,层与层间距的扩大,提供了离子快速传输通道,利于离子传输,进而提高了质量比容量与电化学循环稳定性。(The invention discloses an energy storage carbon material and a preparation method and application thereof, and relates to the technical field of carbon material preparation by heavy oil, wherein the energy storage carbon material is of a layered structure, the thickness of the layer is 3-10 nm, the interlayer spacing is 0.3-0.5 nm, and the particle size is larger than 15 mu m; on the other hand, the expansion of the layer-to-layer distance provides an ion rapid transmission channel, which is beneficial to ion transmission, and further improves the mass specific capacity and the electrochemical cycling stability.)

1. An energy storage carbon material is characterized in that the energy storage carbon material is of a layered structure, the layer thickness is 3-10 nm, the interlayer spacing is 0.3-0.5 nm, and the particle size is larger than 15 microns.

2. The energy storage carbon material of claim 1, wherein the feedstock for the energy storage carbon material comprises: mixing asphalt, a template agent and an asphalt emulsifier;

the template agent comprises a soluble inorganic salt;

preferably, the template further comprises lamellar nano MgO;

preferably, the lamellar nano MgO is in a lamellar structure, the maximum outer diameter is 30-50 nm, and the thickness is 2-10 nm.

3. The energy storage carbon material of claim 2, wherein the soluble inorganic salt is selected from the group consisting of sodium chloride, potassium chloride, lithium chloride, sodium bromide, potassium bromide, lithium bromide, sodium iodide, potassium iodide, and lithium iodide in any one or more combinations.

4. The energy storing carbon material of claim 2, wherein the pitch emulsifier is an amine based compound;

preferably, the asphalt emulsifier is selected from any one of octadecyl trimethyl ammonium chloride, alkylamide polyamine, hexadecyl trimethyl ammonium bromide, alkyl propylene diamine, sodium alkyl sulfonate and sodium fatty alcohol ether sulfate.

5. A method of producing an energy storing carbon material as claimed in any one of claims 1 to 4 comprising the steps of:

obtaining asphalt emulsion after asphalt and asphalt emulsifier are mixed;

ultrasonically mixing the asphalt emulsion and the template agent;

and drying the product after ultrasonic mixing, and then carrying out carbonization treatment.

6. The method of claim 5, wherein the templating agent comprises a soluble inorganic salt;

preferably, the template further comprises lamellar nano MgO;

preferably, when the ultrasonic mixing is performed, the mass ratio of the asphalt to the soluble inorganic salt is 1: (10-30);

when the template agent further comprises lamellar nano MgO, the mass ratio of the asphalt to the lamellar nano MgO is 1: (0.2-2).

7. The production method according to claim 5, wherein the carbonization treatment is performed under the following conditions: carbonizing at 700-1000 ℃ for 1-3 h under the atmosphere of inert gas.

8. The method according to claim 5, wherein the mass ratio of the asphalt to the asphalt emulsifier in the asphalt emulsion is 100: (2-30);

preferably, the mass ratio of the asphalt to the asphalt emulsifier is 100: (2-20).

9. Use of the energy storage carbon material according to any one of claims 1 to 4 or the energy storage carbon material prepared by the preparation method according to any one of claims 5 to 8 in the preparation of a supercapacitor.

10. A supercapacitor, comprising a working electrode, wherein the working electrode is prepared from a material comprising the energy storage carbon material according to any one of claims 1 to 4 or the energy storage carbon material prepared by the preparation method according to any one of claims 5 to 7.

Technical Field

The invention relates to the technical field of carbon materials prepared from heavy oil, and particularly relates to an energy storage carbon material and a preparation method and application thereof.

Background

The super capacitor has the characteristics of high power density, quick charge and discharge, long cycle life, safety, reliability and the like, is widely applied to the military and civil fields, the structure determines the property, the excellent electrochemical performance of the super capacitor is often determined by an active material of an electrode, and a carbon material is widely researched due to higher specific surface area and pore volume, better conductivity and excellent cycle stability.

The heavy oil is a complex mixture consisting of a plurality of aliphatic hydrocarbons, naphthenic hydrocarbons and polycyclic aromatic hydrocarbons, has complex and multi-level composition and structure, contains a large amount of hydrocarbon and non-hydrocarbon compounds, supermolecule aggregates such as colloid, asphaltene and the like, contains a large amount of aromatic hydrocarbon structures and abundant heteroatoms such as S, N and the like, and is a natural raw material for producing the energy storage carbon material for the supercapacitor. Aromatic hydrocarbons and partial heteroatom compounds in the heavy oil are directly synthesized into the energy storage carbon material from bottom to top by a simple and controllable chemical means, and a new way for high value-added utilization of the heavy oil is opened up.

At present, the problems of low specific capacity, poor conductivity and the like generally exist in the carbon material for the common super capacitor. Therefore, the development of a high-conductivity and stable-structure electrode material is particularly important for comprehensively improving the performance of the supercapacitor.

Therefore, scholars at home and abroad carry out a great deal of research and put forward a lot of improvement methods. Patent CN1769165A discloses a method for preparing energy storage carbon material for batteries and double electric layer capacitors by using coal tar pitch and petroleum pitch as mixed carbon sources, which mainly utilizes different heteroatom contents and molecular structure compositions of two carbon sources, and optimizes the carbon material structure by controlling the mixing ratio. But the whole electrochemical performance is poor, and when the material is used for a super capacitor, the mass specific capacity of the device is only 118F/g at the highest when the voltage window is 2V.

A preparation method of a carbon cage structure material is developed in an open innovation laboratory of the university of Japan AIST-Kyoto. The process takes metal salt and organic ligand as raw materials, core-shell MOF is prepared by a series of wet chemical methods, and the carbon cage material is obtained by carbonization. And the regulation and control of the carbon cage structure are realized by introducing Fe ions, so that the three-dimensional embroidered ball-like flower superstructure nano material with the carbon cage structure is prepared, but the synthesis route is too long and the process is complex.

In view of this, the invention is particularly proposed.

Disclosure of Invention

The invention aims to provide an energy storage carbon material and a preparation method and application thereof.

The invention is realized by the following steps:

in a first aspect, an embodiment of the present invention provides an energy storage carbon material, where the energy storage carbon material is a layered structure, a layer thickness is 3 to 10nm, a layer spacing is 0.3 to 0.5nm, and a particle size is greater than 15 μm.

In a second aspect, embodiments of the present invention provide a method for preparing an energy storage carbon material as described in the previous embodiments, comprising the following steps:

obtaining asphalt emulsion after asphalt and asphalt emulsifier are mixed;

ultrasonically mixing the asphalt emulsion and the template agent;

and drying the product after ultrasonic mixing, and then carrying out carbonization treatment.

In a third aspect, the embodiment of the present invention further provides an application of the energy storage carbon material as described in the previous embodiment or the energy storage carbon material prepared by the preparation method as described in the previous embodiment in preparing a supercapacitor.

In a fourth aspect, the embodiment of the present invention further provides a supercapacitor, which includes a working electrode, and a preparation material of the working electrode includes the energy storage carbon material described in the foregoing embodiment or the energy storage carbon material prepared by the preparation method described in the foregoing embodiment.

The invention has the following beneficial effects:

the invention takes asphalt as a carbon source, soluble inorganic salt as a template agent and amino compounds as an asphalt emulsifier to prepare the energy storage carbon material with a laminated structure, the size of which exceeds 15 mu m and the thickness of each layer is less than 10 nm.

Compared with the traditional carbon material for the porous supercapacitor, the carbon material with the layered structure has the advantages that the specific surface area is greatly increased, the contact range with electrolyte is expanded, and the wettability is improved; on the other hand, the expansion of the layer-to-layer distance provides an ion rapid transmission channel, which is beneficial to ion transmission, and further improves the mass specific capacity and the electrochemical cycling stability.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings needed to be used in the embodiments will be briefly described below, it should be understood that the following drawings only illustrate some embodiments of the present invention and therefore should not be considered as limiting the scope, and for those skilled in the art, other related drawings can be obtained according to the drawings without inventive efforts.

FIG. 1 is an SEM (left) and TEM image of the lamellar nano-MgO used in example 9;

FIG. 2 is a carbon material scan obtained without the addition of an emulsifier, an inorganic salt template and lamellar nano-MgO;

FIG. 3 is a scanned graph of the energy storage carbon material for the layered petroleum-based supercapacitor obtained in example 1;

FIG. 4 is a perspective view of the energy storage carbon material for the layered petroleum-based supercapacitor obtained in example 1;

FIG. 5 is an XRD pattern of the energy storage carbon material for the layered petroleum-based supercapacitor of example 1.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below. The examples, in which specific conditions are not specified, were conducted under conventional conditions or conditions recommended by the manufacturer. The reagents or instruments used are not indicated by the manufacturer, and are all conventional products available commercially.

The invention provides an energy storage carbon material, wherein the particle size of the energy storage carbon material is larger than 15 mu m, the energy storage carbon material is of a layered structure, the thickness of a layer is 3-10 nm, and the interlayer spacing is 0.3-0.5 nm.

Compared with the traditional carbon material for the porous supercapacitor, the carbon material with the layered structure has the advantages that the specific surface area is greatly increased, the contact range with electrolyte is expanded, and the wettability is improved; on the other hand, the expansion of the layer-to-layer distance provides an ion rapid transmission channel, which is beneficial to ion transmission, and further improves the mass specific capacity and the electrochemical cycling stability.

The "layer thickness" herein is the thickness of each layer. In some embodiments, the layer(s) of energy storage carbon material may be 3nm, 4nm, 5nm, 6nm, 7nm, 8nm, 9nm, or 10nm thick.

"interlayer spacing" herein refers to the spacing between two adjacent layers. In some embodiments, the interlamellar spacing of the energy storage carbon material may be 0.3nm, 0.35nm, 0.4nm, 0.45nm, or 0.5 nm.

Preferably, the raw material of the energy storage carbon material comprises: mixing asphalt, a template agent and an asphalt emulsifier;

the template agent comprises a soluble inorganic salt;

preferably, the templating agent further includes lamellar nano MgO.

The invention takes asphalt as a carbon source, soluble inorganic salt, lamellar nano MgO as a template agent and amino compounds as an asphalt emulsifier, and is used for preparing the energy storage carbon material with a lamellar structure.

The 'lamellar nano MgO' refers to granular nano MgO, and is in a lamellar structure, lamellar nano MgO can be prepared by a hydrothermal synthesis method or obtained by commercial purchase, and the preparation steps are not repeated.

Preferably, the maximum outer diameter of the lamellar nano MgO is 30-50 nm, and the thickness of the lamellar nano MgO is 2-10 nm.

The "maximum outer diameter" in this context is the longest diameter of the object. In some embodiments, the maximum outer diameter of the lamellar nano-MgO may be 30nm, 32nm, 34nm, 36nm, 38nm, 40nm, 42nm, 44nm, 46nm, 48nm, or 50 nm. The thickness may be 2nm, 4nm, 6nm, 8nm or 10 nm.

Preferably, the soluble inorganic salt is selected from any one or more of sodium chloride, potassium chloride, lithium chloride, sodium bromide, potassium bromide, lithium bromide, sodium iodide, potassium iodide and lithium iodide in combination.

Preferably, the asphalt emulsifier is selected from any one of octadecyl trimethyl ammonium chloride, alkylamide polyamine, hexadecyl trimethyl ammonium bromide, alkyl propylene diamine, sodium alkyl sulfonate and sodium fatty alcohol ether sulfate.

Compared with the prior art, the invention does not need to add various activators, and the emulsifier is an organic matter containing nitrogen and sulfur, and can be decomposed at high temperature, thereby not only enhancing the mixing degree of the asphalt and the template agent, but also introducing nitrogen and sulfur doping. Meanwhile, the template agent adopts inorganic salt with low melting point and high boiling point, and can be recycled by water washing after the reaction is finished.

Furthermore, an embodiment of the present invention provides a method for preparing an energy storage carbon material as described in any of the previous embodiments, comprising the steps of:

obtaining asphalt emulsion after asphalt and asphalt emulsifier are mixed;

ultrasonically mixing the asphalt emulsion and the template agent;

and drying the product after ultrasonic mixing, and then carrying out carbonization treatment.

Preferably, the templating agent comprises a soluble inorganic salt.

More preferably, the templating agent further includes lamellar nano MgO.

Preferably, when the ultrasonic mixing is performed, the mass ratio of the asphalt to the soluble inorganic salt is 1: (10-30). When the template agent further comprises lamellar nano MgO, the mass ratio of the asphalt to the lamellar nano MgO is 1: (0.2-2).

Mixing according to the mass ratio can improve the carbon layer spacing of the energy storage material, and further improve the specific capacity and electrochemical cycling stability of the material.

In some embodiments, the mass ratio of bitumen and soluble inorganic salt may be 1: 10. 1: 12. 1: 14. 1: 16. 1: 18. 1: 20. 1: 22. 1: 24. 1: 26. 1: 28 or 1: 30. the mass ratio of the asphalt to the lamellar nano MgO can be 1:0.2, 1: 0.4, 1: 0.6, 1: 0.8, 1: 1.0, 1: 1.2, 1: 1.4, 1: 1.6, 1: 1.8 or 1: 2.

preferably, the conditions of the carbonization treatment are as follows: carbonizing at 700-1000 ℃ for 1-3 h under the atmosphere of inert gas. The processing conditions can further improve the carbon layer spacing of the energy storage material, thereby being beneficial to improving the specific capacity and the electrochemical cycling stability of the material.

In some embodiments, the temperature of the carbonization treatment may be 700 ℃, 750 ℃, 800 ℃, 850 ℃, 900 ℃, 950 ℃ or 1000 ℃. The time of the carbonization treatment can be 1h, 1.2h, 1.4h, 1.6h, 1.8h, 2.0h, 2.2h, 2.4h, 2.6h, 2.8h or 3.0 h.

Preferably, in the asphalt emulsion, the mass ratio of asphalt to asphalt emulsifier is 100: (2-30).

Preferably, the mass ratio of the asphalt to the asphalt emulsifier is 100: (2-20). The mass ratio is more favorable for improving the performance of the material.

In some embodiments, the mass ratio of bitumen to bitumen emulsifier may be 100: 2. 100, and (2) a step of: 4. 100, and (2) a step of: 6. 100, and (2) a step of: 8. 100, and (2) a step of: 10. 100, and (2) a step of: 12. 100, and (2) a step of: 14. 100, and (2) a step of: 16. 100, and (2) a step of: 18 or 100: 20.

optionally, the asphalt and the asphalt emulsifier are subjected to ultrasonic treatment to obtain the asphalt emulsion. The frequency of ultrasonic treatment is 15-25 kHz, the power is 500-1800W, and the time is 1-3 h.

Preferably, before mixing, the preparation method further comprises grinding the asphalt balls to 150-300 meshes.

Embodiments of the present invention further provide an application of the energy storage carbon material according to any of the foregoing embodiments or the energy storage carbon material prepared by the preparation method according to any of the foregoing embodiments in preparing a supercapacitor.

In addition, the embodiment of the invention also provides a supercapacitor, which comprises a working electrode, wherein the preparation material of the working electrode comprises the energy storage carbon material prepared in any embodiment or the energy storage carbon material prepared by the preparation method in any embodiment.

The features and properties of the present invention are described in further detail below with reference to examples.

Example 1

The invention provides a preparation method of an energy storage carbon material, which comprises the following steps:

(1) preparation of asphalt emulsion

Ball-milling asphalt to 150-300 meshes, sequentially adding asphalt particles and an asphalt emulsifier into deionized water, and carrying out ultrasonic treatment for 2 hours under the conditions that the frequency is 20kHz and the power is 1300W to obtain an asphalt emulsion which is uniformly mixed, wherein the addition amount of the emulsifier is 2% of the mass of the asphalt.

(2) Adding soluble inorganic salt (template) into the asphalt emulsion prepared in the step (1), and carrying out ultrasonic treatment for 3h, wherein the mass ratio of the asphalt to the soluble inorganic salt is 1: 10.

(3) And (3) placing the mixed emulsion prepared in the step (2) in an oven at the temperature of 100-150 ℃, drying the water by distillation, placing the dried mixed emulsion in an inert gas atmosphere, carrying out carbonization treatment for 2 hours at the high temperature of 700 ℃, fully cooling, and then carrying out water washing and acidity to obtain the energy storage carbon material with the layered structure.

(4) And (4) evaporating and recrystallizing the solution washed by water in the step (3), and recovering the inorganic salt template.

Example 2

The invention provides a preparation method of an energy storage carbon material, which is approximately the same as that of example 1, and is different in carbonization treatment temperature, wherein the carbonization treatment temperature is 800 ℃.

Example 3

The invention provides a preparation method of an energy storage carbon material, which is approximately the same as example 2, and is characterized in that the addition amount of an emulsifier is 8% of the mass of asphalt, and the mass ratio of the asphalt to inorganic salt is 1: 20.

Example 4

The invention provides a preparation method of an energy storage carbon material, which is approximately the same as example 3, and is characterized in that the addition amount of an emulsifier is 20% of the mass of asphalt.

Example 5

The invention provides a preparation method of an energy storage carbon material, which is approximately the same as the embodiment 3, and is different in that the time of carbonization treatment is 1 h.

Example 6

The invention provides a preparation method of an energy storage carbon material, which is approximately the same as the embodiment 3, and is different in that the time of carbonization treatment is 3 h.

Example 7

The invention provides a preparation method of an energy storage carbon material, which is substantially the same as example 3, except that the mass ratio of asphalt to an inorganic salt template is 1: 30.

Example 8

The invention provides a preparation method of an energy storage carbon material, which is approximately the same as the embodiment 5, and is characterized in that the temperature of carbonization treatment is 1000 ℃.

Example 9

The invention provides a preparation method of an energy storage carbon material, which is approximately the same as example 3, and is characterized in that a template agent comprises soluble inorganic salt and lamellar nano MgO, the mass ratio of asphalt to the soluble inorganic salt is 1:20, and the mass ratio of asphalt to the lamellar nano MgO is 1: 0.2.

SEM and TEM images of the lamellar nano MgO used in this example are shown in FIG. 1. As can be seen from the figure, the hydrothermally synthesized MgO template has a disk-shaped structure of clusters, an overall size of about 50nm, a thickness of 2-10 nm, and a rich pore distribution on the surface.

Example 10

The invention provides a preparation method of an energy storage carbon material, which is approximately the same as example 3, and is different in that a template agent comprises soluble inorganic salt and lamellar nano MgO, the mass ratio of asphalt to the soluble inorganic salt is 1:20, and the mass ratio of asphalt to the lamellar nano MgO is 1: 1.

Example 11

The invention provides a preparation method of an energy storage carbon material, which is approximately the same as example 3, and is characterized in that a template agent comprises soluble inorganic salt and lamellar nano MgO, the mass ratio of asphalt to the soluble inorganic salt is 1:20, and the mass ratio of asphalt to the lamellar nano MgO is 1: 2.

Example 12

The invention provides a preparation method of an energy storage carbon material, which is approximately the same as that in example 1, and is characterized in that a template agent is sodium chloride (soluble inorganic salt), an asphalt emulsifier is alkylamide polyamine, the addition amount of the emulsifier is 15% of the mass of asphalt, the mass ratio of the asphalt to the soluble inorganic salt is 1:30, and the carbonization treatment is carried out for 2 hours at the high temperature of 800 ℃.

Example 13

The invention provides a preparation method of an energy storage carbon material, which is approximately the same as example 12, and is characterized in that a template agent comprises soluble inorganic salt and lamellar nano MgO, the mass ratio of asphalt to the soluble inorganic salt is 1:30, and the mass ratio of asphalt to the lamellar nano MgO is 1: 1.

Example 14

The invention provides a preparation method of an energy storage carbon material, which is approximately the same as that in example 1, and is characterized in that a template agent is potassium bromide (an inorganic salt template agent), an emulsifier is sodium alkylsulfonate, the addition amount of the emulsifier is 20% of the mass of asphalt, the mass ratio of the asphalt to the inorganic salt is 1:30, and the carbonization treatment is carried out for 2 hours at the high temperature of 800 ℃.

Example 15

The invention provides a preparation method of an energy storage carbon material, which is approximately the same as the embodiment 14, and is characterized in that a template agent comprises soluble inorganic salt and lamellar nano MgO, the mass ratio of asphalt to the inorganic salt is 1:30, and the mass ratio of the asphalt to the lamellar nano MgO is 1: 1.

Test examples

The raw material is asphalt provided by a certain refinery of medium petrochemicals, and the asphalt comprises four components: 1.5% of saturated hydrocarbon, 23.8% of aromatic hydrocarbon, 52.3% of colloid and 22.4% of asphaltene.

The energy storage carbon materials prepared in examples 1 to 15 were mixed with Polytetrafluoroethylene (PTFE) solution at a mass ratio of 90:10, respectively, to prepare working electrodes.

The method comprises the following steps of taking a platinum wire as a counter electrode, saturated calomel as a reference electrode, and 6mol L-1KOH as electrolyte, and performing electrochemical test by adopting an electrochemical workstation of Shanghai Chen Hua CHI660E type, wherein the electrochemical test comprises the following steps: cyclic voltammetry, constant current charging and discharging and the like, wherein the voltage range is-1 to 0V, and the scanning rate of the cyclic voltammetry test is 5 to 200mv s^-1The current density of the constant current charge and discharge test is 0.05-10 Ag^-1The test data of each example are shown in the table1 is shown.

TABLE 1 electrochemical test data for energy storage carbon materials for layered petroleum-based supercapacitors

Capacity retention rate: 20Ag^-1Specific capacity/0.05 Ag^-1Specific capacity.

FIG. 2 is a carbon material scan obtained without the addition of emulsifier, inorganic salt template and lamellar nano-MgO.

FIG. 3 is a scanned image of the energy storage carbon material obtained in example 1.

FIG. 4 is a projection of the energy storage carbon material obtained in example 1.

The figure shows that the size is larger than 15 μm, and the thickness of the layer is 3-10 nm.

FIG. 5 is an XRD pattern of the energy storage carbon material for the layered petroleum-based supercapacitor obtained in example 1, and the carbon layer spacing can be calculated from the 002 peak diffraction peak angle.

The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.