Preparation method and application of hexagonal hole SnO2 (at) Ti3C2 electrode material of high-energy-density all-solid-state supercapacitor

Abstract

The invention relates to a preparation method and application of a hexagonal hole SnO2 (at) Ti3C2 electrode material of a high-energy-density all-solid-state supercapacitor, Ti3AlC2 precursor powder with hexagonal holes is placed in a mixed solution of SnCl4. 5H2O, HCl and CaF2, etching and ion intercalation are synchronously carried out through a microwave reactor at the room temperature, the obtained Sn4 + intercalated multilayer hexagonal hole Ti3C2 powder is mixed with deionized water, and the Sn4 + intercalated multilayer hexagonal hole Ti3C2 electrode material is obtained. And then adding SnCl4. 5H2O and NaOH into the mixed solution, uniformly stirring at room temperature, transferring into a lining of a reaction kettle, and preparing the SnO2-coated Ti3C2 electrode material through microwave assistance of a microwave reactor. The method has the advantages that the process method is simple, convenient and rapid to operate and has good stability, the synthesized SnO2-coated Ti3C2 can keep stable performance in different environments, and the energy density is further improved due to the brought pseudocapacitance attribute.

Description

Technical Field

[0001] The present invention belongs to the field of all-solid-state supercapacitors for new energy vehicles, and particularly relates to a high energy density all-solid-state supercapacitor hexagonal hole SnO 2 @Ti 3 C 2 Preparation method of electrode material and its application. Background Art

[0002] New energy vehicles, with their green and environmentally friendly characteristics, have become a key force in promoting green travel and reducing carbon emissions. They represent the future development direction of the automotive industry. The popularization and development of new energy vehicles can not only reduce dependence on fossil fuels and reduce greenhouse gas emissions, but also promote the optimization of energy structure and industrial upgrading.

[0003] As an ideal energy storage device for new energy vehicles, supercapacitors have the advantages of rapid charging and discharging, long cycle life, and high power output, and have broad development prospects. However, traditional supercapacitors often use organic electrolytes to increase the energy density of capacitors, but the organic electrolytes used are often toxic and prone to leakage during use, posing safety risks to the environment and users. Therefore, it is particularly important to develop safe all-solid-state supercapacitors with high energy density.

[0004] Solid-state supercapacitors significantly improve the safety and stability of energy storage devices for new energy vehicles by using solid electrolytes. The key to improving their performance lies in the optimization of electrode materials. Choosing appropriate electrode materials can greatly increase the energy density of supercapacitors. Among the many electrode materials, two-dimensional layered Ti 3 C 2 It has attracted much attention due to its unique properties. As a representative of the MXene series of materials, it has rich surface functional groups, excellent conductivity and outstanding mechanical flexibility. However, due to the low voltage window, the improvement of its energy density faces a bottleneck. Summary of the invention

[0005] The technical problem to be solved by the present invention is to provide a high energy density all-solid-state supercapacitor hexagonal hole SnO 2 @Ti 3 C 2 Preparation method of electrode material and its application.

[0006] The technical solution of the present invention is: A high energy density all-solid-state supercapacitor with hexagonal holes SnO 2 @Ti 3 C 2 The method for preparing an electrode material comprises the following steps: (1) Preparation of Ti with hexagonal holes3 AlC 2 Precursor powder Ti 3 AlC 2 With ZnCl 2 , CuCl 2 The mixture is uniformly mixed in a molar ratio of (5-7):1:1, reacted in a vacuum hot pressing sintering furnace under the protection of an inert atmosphere, and after the reaction, liquid nitrogen is introduced for cooling, and then ground to 200 meshes to obtain a precursor powder with hexagonal holes; (2) Synchronous preparation of Sn by microwave-assisted etching and ion intercalation 4+ Intercalated multilayer hexagonal pore Ti 3 C 2 SnCl powder 4 ·5H 2 O added to CaF 2 In a mixed etchant with HCl, SnCl 4 ·5H 2 O-CaF 2 -HCl mixed solution, add the precursor powder with hexagonal holes prepared in step (1), mix well, place in a microwave reactor at room temperature, perform microwave-assisted etching and ion intercalation, and then use a concentration of 1 mol·L -1 The solution was washed with dilute hydrochloric acid, then ultrasonically treated at room temperature for 1 h, centrifuged, and the precipitate was washed with deionized water until the solution pH = 6, vacuum filtered, and dried in a vacuum drying oven to obtain Sn 4+ Intercalated multilayer hexagonal pore Ti 3 C 2 powder; (3) Using SnCl 4 ·5H 2 O as a tin source by microwave-assisted synthesis of tin dioxide-coated tin ion intercalated Ti 3 C 2 powder The Sn prepared in step (2) 4+ Intercalated multilayer hexagonal pore Ti 3 C 2 Powder and SnCl 4 ·5H 2 O aqueous solution, adding NaOH to adjust the pH value to 12-13, stirring at room temperature for 20-40 minutes, and then putting it into the lining of the reactor, using microwave-assisted preparation in a microwave reactor, washing with deionized water to a pH value of 6-7, and drying in a vacuum drying oven to obtain tin dioxide-coated tin ion intercalated Ti 3 C 2 (SnO 2 @Ti 3 C 2 )powder.

[0007] Furthermore, in step (1), the inert atmosphere is an argon atmosphere; the head pressure of the vacuum hot pressing sintering furnace is set to 20T, the reaction temperature in the vacuum hot pressing sintering furnace is 700°C to 850°C, and the reaction time is 6h to 12h.

[0008] Furthermore, in step (1), liquid nitrogen is introduced for cooling, and the cooling time is 1 hour.

[0009] Furthermore, in step (2), SnCl 4 ·5H 2 O-CaF 2 -HCl mixed solution, the concentration of HCl is 7 mol·L -1 ~9mol·L -1 , HCl and CaF 2 The molar ratio of SnCl is 5:4. 4 ·5H 2 O concentration is 0.25 mol·L -1 , the precursor powder with hexagonal holes and SnCl 4 ·5H 2 O-CaF 2 The mass volume ratio of the mixed solution of -HCl is 1:20 g·mL -1 .

[0010] Furthermore, in step (1), Ti 3 AlC 2 With ZnCl 2 , CuCl 2 The molar ratio is 5:1:1; in step (2), SnCl 4 ·5H 2 O-CaF 2 -HCl mixed solution, the concentration of HCl is 9 mol·L -1 , Sn 4+ Intercalated hexagonal pore Ti 3 C 2 It has a hexagonal pore structure with a distinct layered morphology, which provides more active sites for ion transport and helps improve capacitance performance.

[0011] Furthermore, in step (2), during pickling, a concentration of 1 mol·L -1 of dilute hydrochloric acid; in step (2), during centrifugation, the centrifugal speed is 3000rpm~5000rpm, and the centrifugal time is 15min.

[0012] Further, in step (3), the SnCl 4 ·5H 2The concentration of O aqueous solution is 0.075 mol·L -1 ~0.15mol·L -1 , Sn in solution 4+ Intercalated Ti 3 C 2 With SnCl 4 ·5H 2 O mass ratio is 1: (1-2), preferably, in step (3), the SnCl 4 ·5H 2 O aqueous solution, SnCl 4 ·5H 2 The mass volume ratio of O to deionized water was 1:40 g / mL.

[0013] Furthermore, in step (2) and step (3), when the microwave reactor is subjected to microwave-assisted reaction, the microwave-assisted power is 300 W, the frequency is 2.45 GHz, the pressure is 2.0 MPa, and the reaction time is 3 h.

[0014] A hexagonal hole SnO prepared by the above preparation method 2 @Ti 3 C 2 The application of electrode materials in all-solid-state supercapacitors as positive and negative electrode materials.

[0015] A hexagonal hole hexagonal hole SnO prepared by the above preparation method 2 @Ti 3 C 2 The application of electrode materials in all-solid-state supercapacitors is characterized by: the all-solid-state supercapacitor is specifically assembled as follows: (1) Preparation of high energy density all-solid-state supercapacitor negative electrode SnO 2 @Ti 3 C 2 The electrode material, acetylene black and PVDF were mixed in a mass ratio of 8.5:1:0.5, and NMP was added dropwise to form a mixed slurry, which was evenly coated on a 1 cm×1 cm nickel foam, rolled flat to form an electrode sheet, and dried in a vacuum drying oven at 80°C for 8 hours to obtain a negative electrode material. (2) The specific steps for preparing the positive electrode of a high energy density all-solid-state supercapacitor electrode are as follows Sn 4+ Intercalated Ti 3 C 2 The electrode material, acetylene black and PVDF were mixed in a mass ratio of 8.5:1:0.5, and NMP was added dropwise to form a mixed slurry, which was evenly coated on a 1 cm×1 cm nickel foam, rolled flat to form an electrode sheet, and dried in a vacuum drying oven at 80°C for 8 h to obtain a positive electrode material. (3) Preparation of electrolyte for high energy density all-solid-state supercapacitors Li 2 S.P. 2 S 5 , LiCl are mixed and ground in a molar ratio of 4.2:1:2, and sintered in a vacuum sintering furnace at 500°C for 5 hours. After cooling, a solid electrolyte is obtained. (4) The specific steps for assembling high energy density all-solid-state supercapacitors are as follows The positive electrode sheet, the negative electrode sheet and the solid electrolyte are assembled into an all-solid-state supercapacitor.

[0016] The beneficial effects of the present invention are: (1) Ti 3 AlC 2 As raw material, ZnCl 2 , CuCl 2 It is a defect inducer. It is easy to prepare through vacuum hot pressing sintering and liquid nitrogen cooling. The reaction temperature is low. The unique hexagonal pore structure provides additional adsorption channels for ions, which helps to improve the capacitance performance. (2) Sn 4+ Intercalated multilayer hexagonal pore Ti 3 C 2 The material can fully expose the active sites through cation intercalation. The in-situ intercalation method of "etching-intercalation" can better increase the interlayer spacing. The cation intercalation plays a supporting role and effectively inhibits the phenomenon of close stacking of the sheets. (3) Microwave-assisted synthesis of tin dioxide-coated tin ion intercalated Ti 3 C 2 Composite material characterized by short rod-like SnO 2 Coated Ti 3 C 2 ;SnO 2 With Ti 3 C 2 The interaction between SnO can greatly improve the conductivity and structural stability. 2 The pseudocapacitive properties brought about by this process allow highly reversible redox reactions to be performed on the electrode surface to store charge, thereby increasing the energy density of all-solid-state supercapacitors.

[0017] The preparation method provided by the invention is simple and quick to operate, has a high yield, and is suitable for large-scale industrial production. BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 The precursor having hexagonal holes in Example 1 of the present invention, Sn 4+ Intercalated multilayer hexagonal pore Ti 3 C2 Tin dioxide coated tin ion intercalated Ti 3 C 2 XRD pattern of powder; Figure 2 Sn in Example 1 of the present invention 4+ Intercalated multilayer hexagonal pore Ti 3 C 2 SEM images of Figure 3 Sn in Example 1 of the present invention 4+ Intercalated multilayer hexagonal pore Ti 3 C 2 A local magnified scanning electron microscope image of Figure 4 The tin dioxide-coated tin ion intercalated Ti with hexagonal holes in Example 1 of the present invention is 3 C 2 SEM images of Figure 5 The tin dioxide-coated tin ion intercalated Ti in Example 1 of the present invention 3 C 2 A local magnified scanning electron microscope image of Figure 6 The tin dioxide-coated tin ion intercalated Ti with hexagonal holes in Example 1 of the present invention is 3 C 2 The relationship between the specific capacity and the charge and discharge cycle of the supercapacitor; Figure 7 The tin dioxide coated tin ion intercalated Ti with hexagonal holes in Example 1 of the present invention 3 C 2 The relationship between the energy density and the power density of the supercapacitor; Figure 8 Sn in Example 2 of the present invention 4+ Intercalated multilayer hexagonal pore Ti 3 C 2 SEM images of powders; Fig. 9 Sn in Example 3 of the present invention 4+ Intercalated multilayer hexagonal pore Ti 3 C 2 SEM images of powders; Fig.10 Sn in Comparative Example 1 of the present invention 4+ Intercalated multilayer Ti 3 C 2 SEM images of Fig.11 The SnCl 4 ·5H 2O as a tin source to synthesize tin dioxide-coated tin ion intercalated Ti 3 C 2 SEM images of powders; Fig.12 The Sn obtained by the non-in-situ intercalation method in Comparative Example 3 of the present invention and the in-situ intercalation method in Example 1 is 4+ Intercalated multilayer hexagonal pore Ti 3 C 2 XRD pattern of powder. DETAILED DESCRIPTION

[0019] Example 1 (1) Preparation of Ti with hexagonal holes 3 AlC 2 Precursor powder Ti 3 AlC 2 With ZnCl 2 , CuCl 2 The mixture was mixed evenly in a molar ratio of 5:1:1, and placed in a vacuum hot pressing sintering furnace under the protection of inert atmosphere argon. The power of the vacuum hot pressing sintering furnace was 65KW, the pressure of the pressure head was set to 20T, and the diameter of the effective contact surface of the pressure head was 90mm. Argon was used as the protective atmosphere in the furnace, the inflation pressure was set to 0.03MPa, and the reaction was carried out at 700℃ for 6 hours. After the reaction was completed, liquid nitrogen was introduced for cooling for 1h, and the precursor powder with hexagonal holes was obtained by grinding to 200 mesh. (2) Synchronous preparation of Sn by microwave-assisted etching and ion intercalation 4+ Intercalated multilayer hexagonal pore Ti 3 C 2 SnCl powder 4 ·5H 2 O added to CaF 2 In a mixed etchant with HCl, SnCl 4 ·5H 2 O-CaF 2 -HCl mixed solution, wherein HCl and CaF 2 The molar ratio is 5:4, and the concentration of HCl is 9 mol·L -1 , SnCl 4 ·5H 2 O concentration is 0.25 mol·L -1 , place 1 g of the precursor powder prepared in step (1) in 20 mL of SnCl 4 ·5H 2 O-CaF 2-HCl mixed solution, in a microwave reactor, the microwave auxiliary power was 300W, the frequency was 2.45GHz, the pressure was 2.0MPa, etching and ion intercalation were carried out simultaneously at room temperature, the reaction time was 3h, and then the concentration was 1mol·L -1 The impurities were washed with dilute hydrochloric acid, and then ultrasonic treatment was performed for 1 hour. The suspension obtained after ultrasonic treatment was placed in a centrifuge at a centrifugal speed of 3000rpm for 15 minutes. After the centrifugation was completed, the supernatant was removed and the precipitate after centrifugation was taken out and washed with deionized water until the solution pH = 6, vacuum filtered, and dried in a vacuum drying oven at 80°C for 8 hours to obtain Sn 4+ Intercalated multilayer hexagonal pore Ti 3 C 2 powder; (3) Using SnCl 4 ·5H 2 O as a tin source by microwave-assisted synthesis of tin dioxide-coated tin ion intercalated Ti 3 C 2 0.5g SnCl powder 4 ·5H 2 O was dissolved in 20 mL of deionized water to obtain SnCl 4 ·5H 2 O aqueous solution, add 0.5g Sn prepared in step (2) 4+ Intercalated multilayer hexagonal pore Ti 3 C 2 The powder was added with NaOH to adjust the pH to 12, stirred at room temperature for 30 min, and then poured into the lining of the reactor. The microwave-assisted reaction was carried out in a microwave reactor at a power of 300 W, a frequency of 2.45 GHz, and a pressure of 2.0 MPa for 3 h. After the reaction was completed, it was washed with deionized water until the pH value was 7, vacuum filtered, and dried in a vacuum drying oven at 80 ° C for 8 hours to obtain tin dioxide-coated tin ion intercalated Ti 3 C 2 (SnO 2 @Ti 3 C 2 )powder; (4) Assembly of all-solid-state supercapacitors ① Preparation of negative electrode sheet Tin dioxide coated tin ions intercalated Ti 3 C 2 The powder as the electrode material, acetylene black and PVDF were mixed in a mass ratio of 8.5:1:0.5, NMP was added dropwise to form a mixed slurry, and the mixed slurry was evenly coated on a 1 cm×1 cm nickel foam, rolled flat to form an electrode sheet, and dried in a vacuum drying oven at 80°C for 8 hours to obtain a negative electrode sheet; ② Preparation of positive electrode Sn4+ Intercalated multilayer hexagonal pore Ti 3 C 2 The powder as electrode material, acetylene black and PVDF were mixed in a mass ratio of 8.5:1:0.5, NMP was added dropwise to form a mixed slurry, and the mixed slurry was evenly coated on a 1cm×1cm nickel foam. The electrode sheet was formed after rolling and flattening, and dried in a vacuum drying oven at 80°C for 8h to obtain a positive electrode sheet; ③ Preparation of solid electrolyte Li 2 S.P. 2 S 5 , LiCl are mixed and ground according to a molar ratio of 4.2:1:2, and vacuum sintered in a vacuum sintering furnace at 500°C for 5 hours, and after cooling, a solid electrolyte is obtained; ④ Assembly of all-solid-state supercapacitors The positive electrode plate of step ②, the negative electrode plate of step ① and the solid electrolyte of step ③ are assembled into an all-solid-state supercapacitor.

[0020] Depend on Figure 1 The X-ray diffraction pattern (XRD) shown in Figure 2 shows that the SnO2-coated Sn ions intercalate Ti 3 C 2 Negative electrode materials and Sn 4+ Intercalated Ti 3 C 2 The positive electrode material was successfully prepared; Figure 2 and Figure 3 The scanning electron microscope image shows that Sn 4+ Intercalated hexagonal pore Ti 3 C 2 It has a hexagonal pore structure, and the hexagonal pores have a distinct layered morphology, which provides more active sites for the storage of ions. Figure 4 As shown in the scanning electron microscope image, tin dioxide-coated tin ion intercalated Ti with hexagonal holes was successfully prepared. 3 C 2 Powder with obvious coating morphology; Figure 5 As shown in the figure, by local magnification, short rod-shaped SnO 2 Coated in Ti 3 C 2 The specific surface area is increased and the double-layer capacitance is improved. 2 , thereby increasing the total specific capacitance.

[0021] Example 2 (1) Preparation of Ti with hexagonal holes 3 AlC 2 Precursor powder Ti 3 AlC 2 With ZnCl2 , CuCl 2 The mixture was mixed evenly in a molar ratio of 6:1:1, and placed in a vacuum hot pressing sintering furnace under the protection of inert atmosphere argon. The power of the vacuum hot pressing sintering furnace was 65KW, the pressure of the pressure head was set to 20T, and the diameter of the effective contact surface of the pressure head was 90mm. Argon was used as the protective atmosphere in the furnace, the inflation pressure was set to 0.03MPa, and the reaction was carried out at 850°C for 12 hours. After the reaction was completed, liquid nitrogen was introduced for cooling for 1 hour, and the precursor powder with hexagonal holes was obtained by grinding to 200 meshes. (2) Synchronous preparation of Sn by microwave-assisted etching and ion intercalation 4+ Intercalated multilayer hexagonal pore Ti 3 C 2 SnCl powder 4 ·5H 2 O added to CaF 2 In a mixed etchant with HCl, SnCl 4 ·5H 2 O-CaF 2 -HCl mixed solution, wherein HCl and CaF 2 The molar ratio is 5:4, and the concentration of HCl is 8 mol·L -1 , SnCl 4 ·5H 2 O concentration is 0.25 mol·L -1 , place 1 g of the precursor powder prepared in step (1) in 20 mL of SnCl 4 ·5H 2 O-CaF 2 -HCl mixed solution, in a microwave reactor, at room temperature, at a power of 300 W, a frequency of 2.45 GHz, and a pressure of 2.0 MPa, the microwave reactor microwave-assisted reaction, simultaneous etching and ion intercalation, the reaction time is 3 h, and then the concentration of 1 mol·L -1 The impurities were washed with dilute hydrochloric acid, and then ultrasonic treatment was performed for 1 hour. The suspension obtained after ultrasonic treatment was placed in a centrifuge at a centrifugal speed of 4000rpm for 15 minutes. After the centrifugation was completed, the supernatant was removed and the precipitate after centrifugation was taken out and washed with deionized water until the solution pH = 6, vacuum filtered, and dried in a vacuum drying oven at 80°C for 8 hours to obtain Sn 4+ Intercalated multilayer hexagonal pore Ti 3 C 2 powder; (3) Using SnCl 4 ·5H 2 O as a tin source by microwave-assisted synthesis of tin dioxide-coated tin ion intercalated Ti 3 C 2 powder 1gSnCl 4 ·5H 2 O was dissolved in 20 mL of deionized water to obtain SnCl 4 ·5H 2 O aqueous solution, add 0.5g Sn prepared in step (2) 4+ Intercalated multilayer hexagonal pore Ti 3 C 2 The powder was added with NaOH to adjust the pH to 12, stirred at room temperature for 30 min, and then poured into the lining of the reactor. The microwave-assisted reaction was carried out in a microwave reactor at a power of 300 W, a frequency of 2.45 GHz, and a pressure of 2.0 MPa for 3 h. After the reaction was completed, it was washed with deionized water until the pH value was 7, vacuum filtered, and dried in a vacuum drying oven at 80 ° C for 8 hours to obtain tin dioxide-coated tin ion intercalated Ti 3 C 2 powder; (4) The assembly of the all-solid-state supercapacitor is the same as in Example 1. Depend on Figure 8 The scanning electron microscope image shows that compared with Example 1, due to the Ti 3 AlC 2 With ZnCl 2 , CuCl 2 The molar ratio is different, resulting in the hexagonal pores not being completely formed, and the hydrochloric acid concentration is low, resulting in the stratification effect being not obvious, which should be the intermediate state of the reaction in Example 1.

[0022] Example 3 (1) Preparation of Ti with hexagonal holes 3 AlC 2 Precursor powder Ti 3 AlC 2 With ZnCl 2 , CuCl 2 The mixture was mixed evenly in a molar ratio of 7:1:1, and placed in a vacuum hot pressing sintering furnace under the protection of inert atmosphere argon. The power of the vacuum hot pressing sintering furnace was 65KW, the pressure of the pressure head was set to 20T, and the diameter of the effective contact surface of the pressure head was 90mm. Argon was used as the protective atmosphere in the furnace, the inflation pressure was set to 0.03MPa, and the reaction was carried out at 800℃ for 9 hours. After the reaction was completed, liquid nitrogen was introduced for cooling for 1h, and the precursor powder with hexagonal holes was obtained by grinding to 200 mesh. (2) Synchronous preparation of Sn by microwave-assisted etching and ion intercalation 4+ Intercalated multilayer hexagonal pore Ti 3 C 2 SnCl powder 4 ·5H 2 O added to CaF2 In a mixed etchant with HCl, SnCl 4 ·5H 2 O-CaF 2 -HCl mixed solution, wherein HCl and CaF 2 The molar ratio is 5:4, and the concentration of HCl is 7 mol·L -1 , SnCl 4 ·5H 2 O concentration is 0.25 mol·L -1 , place 1 g of the precursor powder prepared in step (1) in 20 mL of SnCl 4 ·5H 2 O-CaF 2 -HCl mixed solution, in a microwave reactor, at room temperature, at a power of 300 W, a frequency of 2.45 GHz, and a pressure of 2.0 MPa, the microwave reactor microwave-assisted reaction, simultaneous etching and ion intercalation, the reaction time is 3 h, and then the concentration of 1 mol·L -1 The impurities were washed with dilute hydrochloric acid, and then ultrasonic treatment was performed for 1 hour. The suspension obtained after ultrasonic treatment was placed in a centrifuge at a centrifugal speed of 5000rpm for 15 minutes. After the centrifugation was completed, the supernatant was removed and the precipitate after centrifugation was taken out and washed with deionized water until the solution pH = 6, vacuum filtered, and dried in a vacuum drying oven at 80°C for 8 hours to obtain Sn 4+ Intercalated multilayer hexagonal pore Ti 3 C 2 powder; (3) Using SnCl 4 ·5H 2 O as a tin source by microwave-assisted synthesis of tin dioxide-coated tin ion intercalated Ti 3 C 2 0.75g SnCl powder 4 ·5H 2 O was dissolved in 20 mL of deionized water to obtain SnCl 4 ·5H 2 O aqueous solution, add 0.5g Sn prepared in step (2) 4+ Intercalated multilayer hexagonal pore Ti 3 C 2 The powder was added with NaOH to adjust the pH to 12, stirred at room temperature for 30 min, and then poured into the lining of the reactor. The microwave-assisted reaction was carried out in a microwave reactor at a power of 300 W, a frequency of 2.45 GHz, and a pressure of 2.0 MPa for 3 h. After the reaction was completed, it was washed with deionized water until the pH value was 7, vacuum filtered, and dried in a vacuum drying oven at 80 ° C for 8 hours to obtain tin dioxide-coated tin ion intercalated Ti 3 C2 powder; (4) The assembly of the all-solid-state supercapacitor is the same as in Example 1. Depend on Fig. 9 The scanning electron microscope image shows that compared with Example 1, due to the Ti 3 AlC 2 With ZnCl 2 , CuCl 2 The molar ratio is different, resulting in the hexagonal pores not being fully formed, and the hydrochloric acid concentration is low, resulting in the stratification effect being not obvious, which should be the intermediate state of the reaction in Example 1.

[0023] Comparative Example 1 This comparative example does not utilize vacuum hot pressing sintering and cooling process to sinter Ti 3 AlC 2 Precursor processing (1) Synchronous preparation of Sn by microwave-assisted etching and ion intercalation 4+ Intercalated multilayer Ti 3 C 2 SnCl powder 4 ·5H 2 O added to CaF 2 In a mixed etchant with HCl, SnCl 4 ·5H 2 O-CaF 2 -HCl mixed solution, wherein HCl and CaF 2 The molar ratio is 5:4, and the concentration of HCl is 9 mol·L -1 , SnCl 4 ·5H 2 O concentration is 0.25 mol·L -1 , Ti 3 AlC 2 1g of powder was placed in 20mL of SnCl 4 ·5H 2 O-CaF 2 -HCl mixed solution, in a microwave reactor, at room temperature, at a power of 300 W, a frequency of 2.45 GHz, and a pressure of 2.0 MPa, the microwave reactor microwave-assisted reaction, simultaneous etching and ion intercalation, the reaction time is 3 h, and then the concentration of 1 mol·L -1 The impurities were washed with dilute hydrochloric acid, and then ultrasonic treatment was performed for 1 hour. The suspension obtained after ultrasonic treatment was placed in a centrifuge at a centrifugal speed of 3000rpm for 15 minutes. After the centrifugation was completed, the supernatant was removed and the precipitate after centrifugation was taken out and washed with deionized water until the solution pH = 6, vacuum filtered, and dried in a vacuum drying oven at 80°C for 8 hours to obtain Sn 4+ Intercalated multilayer Ti 3 C2 powder; (2) Using SnCl 4 ·5H 2 O as a tin source by microwave-assisted synthesis of tin dioxide-coated tin ion intercalated Ti 3 C 2 0.5g SnCl powder 4 ·5H 2 O was dissolved in 20 mL of deionized water to obtain SnCl 4 ·5H 2 O aqueous solution, add 0.5g Sn prepared in step (2) 4+ Intercalated multilayer hexagonal pore Ti 3 C 2 The powder was added with NaOH to adjust the pH to 12, stirred at room temperature for 30 min, and then poured into the lining of the reactor. The microwave-assisted reaction was carried out in a microwave reactor at a power of 300 W, a frequency of 2.45 GHz, and a pressure of 2.0 MPa for 3 h. After the reaction was completed, it was washed with deionized water until the pH value was 7, vacuum filtered, and dried in a vacuum drying oven at 80 ° C for 8 hours to obtain tin dioxide-coated tin ion intercalated Ti 3 C 2 powder; (3) Assembly of the all-solid-state supercapacitor is the same as in Example 1 Depend on Fig.10 The scanning electron microscope image shows that Sn without hexagonal holes 4+ Intercalated multilayer Ti 3 C 2 Powder, the specific surface area is compared with Sn in Example 1 4+ Intercalated multilayer hexagonal pore Ti 3 C 2 The powder is significantly reduced, and the additional adsorption channels and redox sites of ions are reduced. As shown in Table 1, the energy density of Comparative Example 1 is 277.58 F g -1 , relatively minimal.

[0024] Comparative Example 2 (1) Preparation of Ti with hexagonal holes 3 AlC 2 Precursor powder Ti 3 AlC 2 With ZnCl 2 , CuCl 2The mixture was mixed evenly in a molar ratio of 5:1:1, and placed in a vacuum hot pressing sintering furnace under the protection of inert atmosphere argon. The power of the vacuum hot pressing sintering furnace was 65KW, the pressure of the pressure head was set to 20T, and the diameter of the effective contact surface of the pressure head was 90mm. Argon was used as the protective atmosphere in the furnace, the inflation pressure was set to 0.03MPa, and the reaction was carried out at 700℃ for 6 hours. After the reaction was completed, liquid nitrogen was introduced for cooling for 1h, and the precursor powder with hexagonal holes was obtained by grinding to 200 mesh. (2) Synchronous preparation of Sn by microwave-assisted etching and ion intercalation 4+ Intercalated multilayer hexagonal pore Ti 3 C 2 SnCl powder 4 ·5H 2 O added to CaF 2 In a mixed etchant with HCl, SnCl 4 ·5H 2 O-CaF 2 -HCl mixed solution, wherein HCl and CaF 2 The molar ratio is 5:4, and the concentration of HCl is 9 mol·L -1 , SnCl 4 ·5H 2 O concentration is 0.25 mol·L -1 , place 1 g of the precursor powder prepared in step (1) in 20 mL of SnCl 4 ·5H 2 O-CaF 2 -HCl mixed solution, in a microwave reactor, at room temperature, at a power of 300 W, a frequency of 2.45 GHz, and a pressure of 2.0 MPa, the microwave reactor microwave-assisted reaction, simultaneous etching and ion intercalation, the reaction time is 3 h, and then the concentration of 1 mol·L -1 The impurities were washed with dilute hydrochloric acid, and then ultrasonic treatment was performed for 1 hour. The suspension obtained after ultrasonic treatment was placed in a centrifuge at a centrifugal speed of 3000rpm for 15 minutes. After the centrifugation was completed, the supernatant was removed and the precipitate after centrifugation was taken out and washed with deionized water until the solution pH = 6, vacuum filtered, and dried in a vacuum drying oven at 80°C for 8 hours to obtain Sn 4+ Intercalated multilayer hexagonal pore Ti 3 C 2 powder; (3) Directly using SnCl without microwave-assisted synthesis 4 ·5H 2 O as a tin source to synthesize tin dioxide-coated tin ion intercalated Ti 3 C 2 0.5g SnCl powder 4 ·5H2 O was dissolved in 20 mL of deionized water to obtain SnCl 4 ·5H 2 O aqueous solution, add 0.5g Sn prepared in step (2) 4+ Intercalated multilayer hexagonal pore Ti 3 C 2 The powder was then added with NaOH to adjust the pH to 12, stirred at room temperature for 30 min, and then poured into the lining of the reactor and reacted at room temperature for 3 h. After the reaction was completed, it was washed with deionized water until the pH value was 7, vacuum filtered, and dried in a vacuum drying oven at 80 ° C for 8 hours to obtain tin dioxide-coated tin ion intercalated Ti 3 C 2 powder; (4) The assembly of the all-solid-state supercapacitor is the same as in Example 1. Comparative Example 2 was tested for charge and discharge cycles under the same conditions as Example 1. Figure 6 As shown. The specific capacitance of comparative example 2 increases with the charge and discharge cycle, and the Ti 3 C 2 The specific capacitance of the comparative example 2 is relatively large, and the long cycle charge and discharge is relatively unstable. When it reaches 50,000 cycles, the Ti 3 C 2 The specific capacitance is from 356.52Fg -1 Change to 244.13F g -1 , the specific capacitance decay rate is 31.52%. And, by Figure 7 The energy density versus power density curves show that the Ti 3 C 2 The energy density of the attenuation increases with the increase of power density. Fig.11 The scanning electron microscopy image shown in the figure shows that the tin dioxide-coated tin ion intercalated Ti 3 C 2 The powder has uneven surface coating, which will lead to differences in electrochemical performance in different areas, affecting the stability and consistency of the overall performance, resulting in low energy density. In addition, the particle size of tin oxide varies, resulting in the TiO2 charge and discharge process. 3 C 2 The electrochemical active sites are not uniform, which reduces the long-cycle specific capacitance stability and energy density stability.

[0025] Comparative Example 3 Etching and ion intercalation are carried out step by step (1) Preparation of Ti with hexagonal holes 3 AlC 2 Precursor powder Ti 3 AlC 2 With ZnCl2 , CuCl 2 The mixture was mixed evenly in a molar ratio of 5:1:1, and placed in a vacuum hot pressing sintering furnace under the protection of inert atmosphere argon. The power of the vacuum hot pressing sintering furnace was 65KW, the pressure of the pressure head was set to 20T, and the diameter of the effective contact surface of the pressure head was 90mm. Argon was used as the protective atmosphere in the furnace, the inflation pressure was set to 0.03MPa, and the reaction was carried out at 700℃ for 6 hours. After the reaction was completed, liquid nitrogen was introduced for cooling for 1h, and the precursor powder with hexagonal holes was obtained by grinding to 200 mesh. (2) Preparation of multilayer hexagonal porous Ti by microwave assisted etching 3 C 2 powder CaF 2 Add to HCl to prepare CaF 2 -HCl mixed etchant, wherein HCl and CaF 2 The molar ratio is 5:4, and the concentration of HCl is 9 mol·L -1 , place 1 g of the precursor powder prepared in step (1) in 20 mL of CaF 2 -HCl mixed etchant, microwave-assisted etching in a microwave reactor at room temperature at 300 W power, 2.45 GHz frequency, 2.0 MPa pressure, reaction time is 3 h, then the concentration of 1 mol·L -1 The impurities were washed with dilute hydrochloric acid, and then ultrasonic treatment was performed for 1 hour. The suspension obtained after ultrasonic treatment was placed in a centrifuge at a centrifugal speed of 3000rpm for 15 minutes. After the centrifugation was completed, the supernatant was removed and the precipitate after centrifugation was washed with deionized water until the solution pH = 6, vacuum filtered, and dried in a vacuum drying oven at 80°C for 8 hours to obtain multilayer hexagonal porous Ti 3 C 2 powder; (3) Preparation of Sn 4+ Intercalated multilayer hexagonal pore Ti 3 C 2 powder The multilayer hexagonal porous Ti prepared in step (2) 3 C 2 1g of powder is placed in 20mL with a concentration of 0.25mol·L -1 SnCl 4 ·5H 2 O solution, stirred at room temperature with magnetic stirring at 500 rpm for 3 h, put the suspension after reaction into a centrifuge at 3000 rpm for 15 min, after centrifugation, pour out the supernatant, take out the precipitate after centrifugation and wash it with deionized water until the solution pH = 6, vacuum filter, dry it in a vacuum drying oven at 80 ° C for 8 h, and obtain Sn4+ Intercalated multilayer hexagonal pore Ti 3 C 2 powder; (4) Using SnCl 4 ·5H 2 O as a tin source by microwave-assisted synthesis of tin dioxide-coated tin ion intercalated Ti 3 C 2 0.5g SnCl powder 4 ·5H 2 O was dissolved in 20 mL of deionized water to obtain a concentration of 0.75 mol·L -1 SnCl 4 ·5H 2 O aqueous solution, add 0.5g Sn prepared in step (2) 4+ Intercalated multilayer hexagonal pore Ti 3 C 2 The powder was added with 0.7 g NaOH to adjust the pH to 12, stirred at room temperature for 30 min, and then poured into the lining of the reactor. The microwave-assisted reaction was carried out in a microwave reactor at a power of 300 W, a frequency of 2.45 GHz, and a pressure of 2.0 MPa for 3 h. After the reaction was completed, it was washed with deionized water until the pH value was 7, vacuum filtered, and dried in a vacuum drying oven at 80 ° C for 8 hours to obtain tin dioxide-coated tin ion intercalated Ti 3 C 2 powder; (5) The assembly of the all-solid-state supercapacitor is the same as in Example 1. Fig.12 From the analysis of the XRD diagram shown, it can be seen that compared with comparative example 3, the 002 peak in Example 1 is shifted to the left by an angle of 2θ=0.18°. Compared with comparative example 3, the simultaneous etching and ion intercalation in Example 1 of the present invention can further increase the interlayer spacing, provide a wider transmission channel for ions, and significantly improve the pseudocapacitance performance of the material. The electrochemical performance of Examples 1 to 3 of the present invention and Comparative Examples 1 to 3 is shown in Table 1: Table 1 Example 1 Example 2 Example 3 Comparative Example 1 Comparative Example 2 Comparative Example 3 Specific Capacitance 685.62F / g 451.04F / g 407.23F / g 277.58F / g 356.52F / g 477.13F / g Energy Density 274.87W / kg 180.82W / kg 163.26W / kg 111.28W / kg 142.93W / kg 191.28W / kg Combination Figure 6 As shown in Table 1, the tin dioxide-coated tin ion intercalated Ti of Example 1 of the present invention 3 C 2 The powder greatly increases the total specific capacitance, which can reach 685.62F g -1 ,Depend on Figure 6 It can be seen that in the long-term charge and discharge cycle process of up to 50,000 cycles, the SnO 2 @Ti 3 C 2The specific capacitance is 685.62F·g -1 Change to 678.76F·g -1 , the specific capacitance decay rate is 1%, and the cycle stability is good. Figure 1 As shown in Table 1, the all-solid-state supercapacitor of Example 1 of the present invention is coated with tin dioxide and tin ion intercalated Ti 3 C 2 The powder greatly improves the energy density, which can reach 274.87Wh kg -1 , achieving high energy density energy storage.

[0026] The above are only specific embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A method for preparing a high energy density all-solid-state supercapacitor hexagonal hole SnO2@Ti3C2 electrode material, characterized by: The following steps are involved: (1) Preparation of Ti3AlC2 precursor powder with hexagonal pores Ti3AlC2 is mixed with ZnCl2 and CuCl2 in a molar ratio of (5-7): 1:1, and reacted in a vacuum hot pressing sintering furnace under the protection of an inert atmosphere. After the reaction is completed, liquid nitrogen is introduced for cooling, and then ground into 200 meshes to obtain a precursor powder with hexagonal holes. (2) Synchronous preparation of Sn by microwave-assisted etching and ion intercalation 4+ Intercalated multilayer hexagonal pore Ti3C2 powder: SnCl4·5H2O is added to a mixed etchant of CaF2 and HCl to prepare a SnCl4·5H2O-CaF2-HCl mixed solution, and the precursor powder with hexagonal pores prepared in step (1) is added and mixed evenly, and poured into a microwave reactor at room temperature to perform microwave-assisted etching and ion intercalation in the microwave reactor, and then acid-washed, and then ultrasonically treated at room temperature for 1 hour, centrifuged, and the precipitate is retained and washed with deionized water until the solution pH = 6, vacuum filtered, and dried in a vacuum drying oven to obtain Sn 4+ Intercalated multi-layer hexagonal pore Ti3C2 powder; (3) Using SnCl4·5H2O as a tin source, microwave-assisted synthesis of tin dioxide-coated tin ion intercalated Ti3C2 powder was used to prepare Sn2O3 4+ The intercalated multilayer hexagonal pore Ti3C2 powder and SnCl4·5H2O aqueous solution are mixed with NaOH to adjust the pH value to 12-13, stirred at room temperature for 20-40 minutes, and then placed in the lining of a reactor, prepared by microwave-assisted microwave reactor, washed with deionized water to a pH value of 6-7, and dried in a vacuum drying oven to obtain tin dioxide-coated tin ion intercalated Ti3C2 powder.

2. The method for preparing the high energy density all-solid-state supercapacitor hexagonal hole SnO2@Ti3C2 electrode material according to claim 1, characterized in that: In step (1), the inert atmosphere is an argon atmosphere; the head pressure of the vacuum hot pressing sintering furnace is set to 20T, the reaction temperature in the vacuum hot pressing sintering furnace is 700°C to 850°C, and the reaction time is 6h to 12h.

3. The method for preparing the high energy density all-solid-state supercapacitor hexagonal hole SnO2@Ti3C2 electrode material according to claim 1, characterized in that: In step (2), the concentration of HCl in the SnCl4·5H2O-CaF2-HCl mixed solution is 7 mol·L -1 ~9mol·L -1 The molar ratio of HCl to CaF2 is 5:4, and the concentration of SnCl4·5H2O is 0.25 mol·L -1 The mass volume ratio of the precursor powder with hexagonal pores to the SnCl4·5H2O-CaF2-HCl mixed solution is 1:20 g·mL -1 .

4. The method for preparing the high energy density all-solid-state supercapacitor hexagonal hole SnO2@Ti3C2 electrode material according to claim 1, characterized in that: In step (3), the concentration of the SnCl4·5H2O aqueous solution is 0.07 mol·L -1 ~0.15mol·L -1 , Sn 4+ The mass ratio of the intercalated multilayer hexagonal porous Ti3C2 powder to SnCl4·5H2O in the SnCl4·5H2O aqueous solution is 1:(1:2).

5. The method for preparing the high energy density all-solid-state supercapacitor hexagonal hole SnO2@Ti3C2 electrode material according to claim 3 or 4, characterized in that: step( 1), the molar ratio of Ti3AlC2 to ZnCl2 and CuCl2 is 5:1:1; in step (2), the concentration of HCl in the SnCl4·5H2O-CaF2-HCl mixed solution is 9 mol·L -1 .

6. The method for preparing the high energy density all-solid-state supercapacitor hexagonal hole SnO2@Ti3C2 electrode material according to claim 1, characterized in that: In step (3), in the SnCl4·5H2O aqueous solution, the mass volume ratio of SnCl4·5H2O to deionized water is 1:40 g / mL.

7. The method for preparing the high energy density all-solid-state supercapacitor hexagonal hole SnO2@Ti3C2 electrode material according to claim 1, characterized in that: In step (1), when liquid nitrogen is introduced for cooling, the cooling time is 1 hour; in step (2), when pickling, a concentration of 1 mol·L -1 of dilute hydrochloric acid; in step (2), during centrifugation, the centrifugal speed is 3000rpm~5000rpm, and the centrifugal time is 15min.

8. The method for preparing the high energy density all-solid-state supercapacitor hexagonal hole SnO2@Ti3C2 electrode material according to claim 1, characterized in that: In step (2) and step (3), when the microwave reactor is microwave-assisted, the microwave-assisted power is 300 W, the frequency is 2.45 GHz, the pressure is 2.0 MPa, and the reaction time is 3 h.

9. Use of the hexagonal pore SnO2@Ti3C2 electrode material prepared by the preparation method as claimed in claim 1 as a positive electrode material and a negative electrode material in an all-solid-state supercapacitor.

10. A use as claimed in claim 1, characterized in that: The specific assembly of supercapacitor is as follows: (1) Preparation of high energy density all-solid-state supercapacitor negative electrode SnO2@Ti3C2 electrode material, acetylene black and PVDF were mixed in a mass ratio of 8.5:1:0.5, NMP was added dropwise to form a mixed slurry, and the mixed slurry was evenly coated on a 1cm×1cm nickel foam, rolled and flattened to form an electrode sheet, and dried in a vacuum oven to obtain a negative electrode material; (2) Preparation of positive electrode for high energy density all-solid-state supercapacitor electrodes Sn 4+ The intercalated Ti3C2 electrode material, acetylene black and PVDF were mixed in a mass ratio of 8.5:1:0.5, NMP was added dropwise to form a mixed slurry, and the mixed slurry was evenly coated on a 1 cm×1 cm nickel foam, and the electrode sheet was formed after rolling and flattening, and the positive electrode material was obtained in a vacuum drying oven; (3) Preparation of electrolyte for high energy density all-solid-state supercapacitors Li2S, P2S5, and LiCl were mixed and ground in a molar ratio of 4.2:1:2, and sintered in a vacuum furnace at 500°C for 5 h. After cooling, a solid electrolyte was obtained. (4) Assembly of high energy density all-solid-state supercapacitors The positive electrode sheet, the negative electrode sheet and the solid electrolyte are assembled into an all-solid-state supercapacitor.

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