Preparation and application of carboxymethyl cellulose derived porous carbon loaded phosphorus copper sulfide and cuprous sulfide electrode material
Porous carbon electrode materials were prepared by using sodium carboxymethylcellulose to support phosphorus copper sulfide and copper sulfide, which solved the problems of complex and high cost of the existing electrode materials preparation process, and achieved high performance and low cost supercapacitor electrode materials.
Patent Information
- Application Number
- CN202510036846.9
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-01-09
- Publication Date
- 2025-05-02
AI Technical Summary
The preparation process of existing supercapacitor electrode materials is complex and costly, and the raw materials of traditional carbon materials are scarce, making it difficult to meet the needs of large-scale applications.
Sodium carboxymethylcellulose is used as the biomass material, and a metal composite material derived from carboxymethylcellulose-derived porous carbon-supported copper sulfide and copper sulfide is prepared as the electrode material for the supercapacitor by loading transition metal phosphide and sulfide.
It realizes a supercapacitor electrode material prepared from biomass as raw material, with excellent specific capacitance and cyclic charging and discharging performance, and is simple in process and low in cost, which meets the requirements of commercial applications.
Smart Images
Figure HDA0005235768750000011 
Figure HDA0005235768750000021 
Figure HDA0005235768750000031
Abstract
Description
Technical Field
[0001] The invention belongs to the field of new energy materials and relates to the preparation and application of a supercapacitor electrode material of a metal composite material of copper phosphosulfide and cuprous sulfide loaded on carboxymethyl cellulose-derived porous carbon. Background Art
[0002] As people's demand for fossil fuels continues to increase, the environmental crisis is also gradually increasing. In addition, due to the widespread use of new energy vehicles and portable electronic devices, clean energy and energy storage equipment are widely favored by people. Among them, supercapacitors have the characteristics of high power density, ultra-fast charging and discharging, good stability, long cycle life, and clean and pollution-free. Therefore, they have attracted much attention as a high-efficiency energy storage device.
[0003] Among all the components of supercapacitors, electrode materials are the key to their energy conversion. Carbon materials are currently the most commercialized electrode materials. However, non-renewable raw materials such as coal and petroleum coke used in the production of traditional activated carbon are becoming increasingly scarce. At the same time, the preparation process of new carbon materials such as graphene and carbon nanotubes is cumbersome and expensive. Therefore, biomass is selected as the carbon-containing precursor because it is easy to obtain, environmentally friendly, and low in cost, making it the best choice for electrode materials. Summary of the invention
[0004] The present invention aims to provide a preparation method of a carboxymethyl cellulose-derived porous carbon-loaded copper phosphide and cuprous sulfide electrode material and its application in a supercapacitor. Biomass is used as a carbon-containing precursor and a supercapacitor electrode material with excellent specific capacitance and stable cyclic charge and discharge performance is prepared by loading transition metal phosphides.
[0005] A method for preparing a carboxymethyl cellulose-derived porous carbon-supported copper phosphosulfide and cuprous sulfide electrode material comprises the following process steps:
[0006] (1) slowly dripping a sodium carboxymethyl cellulose solution into a copper nitrate solution to obtain a carboxymethyl cellulose hydrogel loaded with metallic copper, storing the hydrogel at room temperature for 10 to 12 hours, then freezing the hydrogel, and then freeze-drying the hydrogel;
[0007] (2) The sample obtained in step (1) is subjected to high temperature vulcanization, and then dried to obtain a vulcanized sample.
[0008] (3) Phosphating the sample obtained in step (2), and then washing, filtering, and drying to obtain carboxymethyl cellulose-derived porous carbon-supported copper phosphosulfide and cuprous sulfide electrode materials.
[0009] Based on the above technical solution, preferably, in step (1), the ratio of the sodium carboxymethyl cellulose to the deionized water in the copper nitrate solution is 2-4 g:100 mL.
[0010] Based on the above technical solution, preferably, in step (1), the mass concentration of sodium carboxymethyl cellulose in the sodium carboxymethyl cellulose solution is 2 wt.% to 4 wt.%.
[0011] Based on the above technical solution, preferably, in step (1), the mass concentration of copper nitrate in the copper nitrate solution is 2 wt.% to 4 wt.%.
[0012] Based on the above technical scheme, preferably, in step (1), the method for preparing the copper nitrate solution is: dissolving copper nitrate in deionized water, stirring at room temperature for 5 to 10 minutes until it is completely dissolved, to obtain a copper nitrate solution.
[0013] Based on the above technical scheme, preferably, in step (1), the conditions for the frozen storage are: temperature -60 to -40°C, time 8 to 12 hours; the conditions for the freeze-drying are: temperature -70 to -40°C, pressure 0 to 50 Pa, time 10 to 12 hours.
[0014] Based on the above technical solution, preferably, in step (1), the sodium carboxymethyl cellulose solution is slowly dripped into the copper nitrate solution by dripping the sodium carboxymethyl cellulose solution into the copper nitrate solution drop by drop.
[0015] Based on the above technical solution, preferably, in step (2), the vulcanization conditions are: temperature 600-800°C, insulation time 1-2h; the vulcanization is carried out under nitrogen protection, and the vulcanization process adopts a tubular furnace program heating, and the speed range of heating to the vulcanization temperature is 0.5-10°C min -1 .
[0016] Based on the above technical solution, preferably, in step (3), the phosphating conditions are: temperature 300-700°C, holding time 1-2h; the phosphating is carried out under nitrogen protection, and the phosphating process adopts a tubular furnace program heating, and the speed range of heating to the phosphating temperature is 0.5-10°C min -1 .
[0017] Based on the above technical solution, preferably, in step (3), the liquid used for washing is deionized water.
[0018] Based on the above technical solution, preferably, in steps (2) and (3), the drying temperature is 50 to 80°C.
[0019] As a biomass material, sodium carboxymethyl cellulose has the advantages of a special layered porous structure and a large specific surface area. When it is used as a carbon-based material to chelate with transition metal phosphides and transition metal sulfides to prepare electrodes, it can promote the interaction between electrolytes and electrodes and optimize the storage and conversion efficiency of electrical energy.
[0020] The invention also relates to the copper phosphosulfide and cuprous sulfide electrode material supported by the carboxymethyl cellulose derived porous carbon prepared by the protection method.
[0021] The present invention also provides application of the above-mentioned carboxymethyl cellulose derived porous carbon supported copper phosphosulfide and cuprous sulfide electrode material in supercapacitors.
[0022] The advantages of the present invention over existing technologies are as follows:
[0023] (1) The present invention uses sodium carboxymethyl cellulose as raw material, which has a wide source and low cost. The composite material preparation process is simple, the operation process is stable and clean without secondary pollution, and it meets the commercial requirements as a supercapacitor electrode material.
[0024] (2) The unique microstructure of the porous carbon electrode material derived from sodium carboxymethyl cellulose is beneficial to the charge and mass transfer processes in the electrochemical process.
[0025] (3) The present invention uses sodium carboxymethyl cellulose as a source carbon-based material, and prepares a composite material by loading transition metal phosphides and transition metal sulfides as a supercapacitor electrode material, which effectively increases its conductivity and exhibits excellent pseudocapacitive properties. BRIEF DESCRIPTION OF THE DRAWINGS
[0026] Figure 1 is an X-ray diffraction pattern of the copper phosphosulfide and cuprous sulfide metal composite material supported by carboxymethyl cellulose-derived porous carbon prepared in Example 1 as an electrode material;
[0027] Figure 2 is a scanning electron microscope image of the copper phosphosulfide and cuprous sulfide metal composite material supported by carboxymethyl cellulose-derived porous carbon prepared in Example 1 as an electrode material;
[0028] Figure 3 The copper phosphosulfide and cuprous sulfide metal composite material supported by the carboxymethyl cellulose-derived porous carbon prepared in Example 1 was used as the electrode material in 6 mol L -1 Cyclic voltammograms at different scan rates in KOH electrolyte;
[0029] Figure 4 The copper phosphosulfide and cuprous sulfide metal composite material supported by the carboxymethyl cellulose-derived porous carbon prepared in Example 1 was used as the electrode material in 6 mol L -1Constant current charge and discharge curves at different current densities in KOH electrolyte.
[0030] Figure 5 The copper phosphosulfide and cuprous sulfide metal composite material supported by the carboxymethyl cellulose-derived porous carbon prepared in Example 1 was used as the electrode material in 6 mol L -1 AC impedance diagram in KOH electrolyte.
[0031] Figure 6 The copper phosphosulfide and cuprous sulfide metal composite material supported by the carboxymethyl cellulose-derived porous carbon prepared in Example 1 was used as the electrode material in 6 mol L -1 The current density in the KOH electrolyte is 10Ag -1 Cyclic stability test diagram. DETAILED DESCRIPTION
[0032] The following is a detailed description of the preparation of the copper phosphosulfide and cuprous sulfide metal composite material loaded with sodium carboxymethyl cellulose as a carbon-based material and the preparation of its electrode material and its electrochemical properties through specific examples.
[0033] Example 1
[0034] 1. Preparation of copper phosphosulfide and cuprous sulfide metal composites supported on carboxymethyl cellulose-derived porous carbon
[0035] (1) Add 3 g of copper nitrate to 100 mL of deionized water and stir at room temperature for 10 min until it is completely dissolved to obtain a copper phosphide solution.
[0036] (2) Add 2 g of sodium carboxymethyl cellulose to 100 mL of deionized water and stir at room temperature for 10 h until the sodium carboxymethyl cellulose is completely dissolved to obtain a sodium carboxymethyl cellulose solution.
[0037] (3) The sodium carboxymethyl cellulose solution was added dropwise into the copper nitrate solution and kept at room temperature for 10 h. The carboxymethyl cellulose loaded with metallic copper was obtained by filtration, and then frozen in a refrigerator at -50°C for 10 h, and then vacuum freeze-dried in a vacuum freeze dryer at -50°C and 10 Pa for 12 h.
[0038] (4) The sample obtained in step (3) was heated in a tube furnace at 5°C for 10 min. -1 The temperature was raised to 700°C for vulcanization, kept at that temperature for 2 hours, then dropped to room temperature, and dried in an oven at 60°C for 12 hours to obtain a vulcanized sample.
[0039] (5) The sample obtained in step (4) was heated in a tube furnace at 5°C for 10 min. -1The temperature was programmed to 500°C for phosphating, kept for 2 hours, then cooled to room temperature, washed with deionized water, filtered, and dried in an oven at 60°C for 12 hours to obtain a carboxymethyl cellulose-derived porous carbon-loaded copper phosphosulfide and cuprous sulfide metal composite material (Cu2S-Cu7PS6@C), which was used as an electrode material for supercapacitors.
[0040] Figure 1 This is the X-ray diffraction pattern of the supercapacitor electrode material (Cu2S-Cu7PS6@C) prepared above. In the figure, Cu2S and Cu7PS6 seeds corresponding to different lattice planes appear, proving that Cu2S and Cu7PS6 are successfully loaded on carboxymethyl cellulose, thereby obtaining a carboxymethyl cellulose-derived porous carbon loaded with copper phosphosulfide and cuprous sulfide electrode material.
[0041] Figure 2 The above-prepared supercapacitor electrode material (Cu2S-Cu7PS6@C) is a scanning electron microscope image. Figures (a)-(d) are scanned images at ×65, ×500, ×10000, and ×30000 magnifications, respectively. It can be observed from the figure that the prepared electrode material perfectly inherits the honeycomb porous structure of carboxymethyl cellulose, which is conducive to shortening the transmission path of electrolyte ions and facilitating the storage of ions. In addition, copper phosphosulfide and cuprous sulfide nanoparticles (100-150nm) are uniformly grown in each cavity. This proves that the electrode material of carboxymethyl cellulose-derived porous carbon loaded with copper phosphosulfide and cuprous sulfide has been successfully prepared.
[0042] 2. Preparation of Electrodes
[0043] The copper phosphosulfide and cuprous sulfide metal composite material supported by carboxymethyl cellulose-derived porous carbon prepared above was ground into powder in an agate mortar, 4 mg was mixed evenly with 0.5 mg acetylene black and 0.5 mg polytetrafluoroethylene, and then coated on foamed nickel (1 cm×1 cm), vacuum dried at 60°C for 12 h, and pressed on a tablet press at 6 MPa for 2 min to obtain a test electrode.
[0044] 3. Test of electrochemical performance
[0045] The electrode prepared above was used as the working electrode, the platinum wire was used as the counter electrode, and the saturated calomel electrode was used as the reference electrode to form a three-electrode system. The electrolyte was 6 mol / L -1 The electrochemical performance was tested in KOH solution with a voltage window range of -0.2 to 0.8 V.
[0046] Figure 3 The supercapacitor electrode material (Cu2S-Cu7PS6@C) prepared above was heated to 6 mol / L -1The cyclic voltammetry (CV) curves at different scan rates in the KOH electrolyte with a voltage window range of -0.2 to 0.8 V were obtained. The results show that the CV curves at all scan rates show a pair of redox peaks, and as the scan rate increases, the degree of distortion of the CV curve is small, which proves that the prepared composite material has a good capacitance ratio and is suitable for use as a supercapacitor electrode material.
[0047] Figure 4 The supercapacitor electrode material (Cu2S-Cu7PS6@C) prepared above was heated to 6 mol / L -1 In the KOH electrolyte, the voltage window is 0~0.48V, and the constant current charge and discharge curves at different current densities are shown in the figure. As can be seen from the figure, when the current density is 0.5Ag -1 When the prepared electrode material achieved a high -1 When the current density increases to 10A -1 When the electrode material can still maintain a high specific capacitance of 3226.5Fg -1 This proves that the prepared composite material has excellent electrochemical performance. Figure 3 The CV curve test results are consistent with those of
[0048] Figure 5 The supercapacitor electrode material (Cu2S-Cu7PS6@C) prepared above was heated to 6 mol / L -1 The AC impedance diagram in the KOH electrolyte with a frequency range of 0.1-100kHz. As can be seen from the figure, the charge transfer resistance of the composite material is small, and the slope of the linear part in the low-frequency region is small, which shows that the composite material has a small ion diffusion resistance in the electrolyte and a fast electron transfer speed, and has the potential to be used as a supercapacitor electrode material.
[0049] Figure 6 The supercapacitor electrode material (Cu2S-Cu7PS6@C) prepared above was heated to 6 mol / L -1 In KOH electrolyte, the voltage window is 0-1.5V and the current density is 10Ag -1 The cycle stability test diagram below shows that the capacitance retention rate of the composite material can still reach 99.32% after 10,000 cycles, which proves that the prepared composite material has a high cycle life and has the potential to be used as a supercapacitor electrode material.
[0050] The above-mentioned copper phosphosulfide and cuprous sulfide metal composite material supported by carboxymethyl cellulose-derived porous carbon exhibits excellent electrochemical properties such as high electrochemical capacitance behavior and good cycle stability, and can therefore be used as a supercapacitor electrode material.
[0051] Example 2
[0052] 1. Preparation of copper phosphosulfide and cuprous sulfide metal composites supported on carboxymethyl cellulose-derived porous carbon
[0053] (1) Add 3 g of copper nitrate to 100 mL of deionized water and stir at room temperature for 10 min until it is completely dissolved to obtain a copper nitrate solution.
[0054] (2) Add 2 g of sodium carboxymethyl cellulose to 100 mL of deionized water and stir at room temperature for 10 h until the sodium carboxymethyl cellulose is completely dissolved to obtain a sodium carboxymethyl cellulose solution.
[0055] (3) The sodium carboxymethyl cellulose solution was added dropwise into the copper nitrate solution and kept at room temperature for 10 h. The carboxymethyl cellulose loaded with metallic copper was obtained by filtration, and then frozen in a refrigerator at -50°C for 10 h, and then vacuum freeze-dried in a vacuum freeze dryer at -50°C and 10 Pa for 12 h.
[0056] (4) The sample obtained in step (3) was heated in a tube furnace at 5°C for 10 min. -1 The temperature was raised to 800°C for vulcanization, kept at that temperature for 2 hours, then dropped to room temperature, and dried in an oven at 60°C for 12 hours to obtain a vulcanized sample.
[0057] (5) The sample obtained in step (4) was heated in a tube furnace at 5°C for 10 min. -1 The temperature was programmed to rise to 600°C for phosphating, kept for 2 hours, then cooled to room temperature, washed with deionized water, filtered, and dried in an oven at 60°C for 12 hours to obtain a carboxymethyl cellulose-derived porous carbon-loaded copper phosphosulfide and cuprous sulfide metal composite material, which was used as an electrode material for a supercapacitor.
[0058] 2. Preparation of Electrodes
[0059] The copper phosphosulfide and cuprous sulfide metal composite material supported by carboxymethyl cellulose-derived porous carbon prepared above was ground into powder in an agate mortar, 4 mg was mixed evenly with 0.5 mg acetylene black and 0.5 mg polytetrafluoroethylene, and then coated on foamed nickel (1 cm×1 cm), vacuum dried at 60°C for 12 h, and pressed on a tablet press at 6 MPa for 2 min to obtain a test electrode.
[0060] Example 3
[0061] 1. Preparation of copper phosphosulfide and cuprous sulfide metal composites supported on carboxymethyl cellulose-derived porous carbon
[0062] (1) Add 3 g of copper nitrate to 100 mL of deionized water and stir at room temperature for 10 min until it is completely dissolved to obtain a copper nitrate solution.
[0063] (2) Add 2 g of sodium carboxymethyl cellulose to 100 mL of deionized water and stir at room temperature for 10 h until the sodium carboxymethyl cellulose is completely dissolved to obtain a sodium carboxymethyl cellulose solution.
[0064] (3) The sodium carboxymethyl cellulose solution was added dropwise into the copper nitrate solution and kept at room temperature for 10 h. The carboxymethyl cellulose loaded with metallic copper was obtained by filtration, and then frozen in a refrigerator at -50°C for 10 h, and then vacuum freeze-dried in a vacuum freeze dryer at -50°C and 10 Pa for 12 h.
[0065] (4) The sample obtained in step (3) was heated in a tube furnace at 5°C for 10 min. -1 The temperature was raised to 600°C for vulcanization, kept at this temperature for 2 hours, then dropped to room temperature, and dried in an oven at 60°C for 12 hours to obtain a vulcanized sample.
[0066] (5) The sample obtained in step (4) was heated in a tube furnace at 5°C for 10 min. -1 The temperature was programmed to 700°C for phosphating, kept for 2 hours, then cooled to room temperature, washed with deionized water, filtered, and dried in an oven at 60°C for 12 hours to obtain a carboxymethyl cellulose-derived porous carbon-loaded copper phosphosulfide and cuprous sulfide metal composite material, which was used as an electrode material for a supercapacitor.
[0067] 2. Preparation of Electrodes
[0068] The copper phosphosulfide and cuprous sulfide metal composite material supported by carboxymethyl cellulose-derived porous carbon prepared above was ground into powder in an agate mortar, 4 mg was mixed evenly with 0.5 mg acetylene black and 0.5 mg polytetrafluoroethylene, and then coated on foamed nickel (1 cm×1 cm), vacuum dried at 60°C for 12 h, and pressed on a tablet press at 6 MPa for 2 min to obtain a test electrode.
Claims
1. A method for preparing a carboxymethyl cellulose-derived porous carbon-supported copper phosphosulfide and cuprous sulfide electrode material, characterized in that: The process steps include: (1) dropping a sodium carboxymethyl cellulose solution into a copper nitrate solution to obtain a carboxymethyl cellulose hydrogel loaded with metallic copper, storing the hydrogel at room temperature for 10 to 12 hours, freezing the hydrogel, and then freeze-drying the hydrogel; (2) subjecting the sample obtained in step (1) to high temperature vulcanization and then drying; (3) Phosphating the sample obtained in step (2), and then washing, filtering, and drying to obtain carboxymethyl cellulose-derived porous carbon-supported copper phosphosulfide and cuprous sulfide electrode materials.
2. The preparation method according to claim 1, characterized in that: In step (1), the mass concentration of sodium carboxymethyl cellulose in the sodium carboxymethyl cellulose solution is 2wt.% to 4wt.%; the mass concentration of copper nitrate in the copper nitrate solution is 2wt.% to 4wt.%; and the ratio of sodium carboxymethyl cellulose to deionized water in the copper nitrate solution is 2 to 4g:100mL.
3. The preparation method according to claim 1, characterized in that: In step (1), the conditions for the frozen storage are: temperature -60 to -40°C, time 8 to 12 hours; the conditions for the freeze-drying are: temperature -70 to -40°C, pressure 0 to 50 Pa, time 10 to 12 hours.
4. The preparation method according to claim 1, characterized in that: In step (2), the vulcanization conditions are: temperature 600-800° C., and insulation time 1-2 h.
5. The preparation method according to claim 1, characterized in that: In step (2), the vulcanization is carried out under nitrogen protection, and the speed of heating to the vulcanization temperature is 0.5-10°C min -1 .
6. The preparation method according to claim 1, characterized in that: In step (3), the phosphating conditions are: temperature 300-700° C., and insulation time 1-2 h.
7. The preparation method according to claim 1, characterized in that: In step (3), the phosphating is carried out under nitrogen protection, and the speed of heating to the phosphating temperature is 0.5-10°C min -1 .
8. The preparation method according to claim 1, characterized in that: In steps (2) and (3), the drying temperature is 50 to 80°C.
9. Carboxymethyl cellulose derived porous carbon supported copper phosphosulfide and cuprous sulfide electrode material prepared by the method according to any one of claims 1 to 8.
10. Use of the carboxymethyl cellulose derived porous carbon supported copper phosphosulfide and cuprous sulfide electrode material as claimed in claim 9 in supercapacitors.