Selenium-doped MXene composite nano-material, and preparation method and use thereof
The present invention discloses a selenium-doped MXene composite nano-material and a preparation method thereof, comprising the following steps: (1) adding MXene and an organic selenium source into a dispersant, and stirring to prepare a dispersion with a concentration of 1 mg/ml to 100 mg/ml; (2) transferring the dispersion into a reaction kettle, then heating, reacting, and then naturally cooling to a room temperature; (3) washing the product obtained in the step (2) with a cleaning agent, then centrifuging to collect a precipitate, and drying the precipitate under vacuum; and (4) placing the sample obtained in the step (3) into a tubular furnace for calcination, introducing protective gas, heating, and then cooling to a room temperature to obtain the selenium-doped MXene composite nano-material. The material prepared by the present invention has high specific surface area, good electrical conductivity, cycle stability performance, rate performance and high theoretical specific capacity.
1. A method of preparing a selenium-doped MXene composite nano-material, comprising:
(1) adding a MXene and an organic selenium source into a dispersant, and stirring to prepare a dispersion with a concentration of 1 mg/ml to 100 mg/ml, wherein a mass ratio of the MXene to the organic selenium source is 1:1 to 10, wherein the dispersion concentration is the concentration of the MXene and the organic selenium source;
(2) transferring the dispersion into a reaction kettle, then heating to 100° C. to 220° C., reacting for 10 h to 30 h, and then naturally cooling to a room temperature to form a product;
(3) washing the product obtained in the step (2) with a cleaning agent, centrifuging to collect a precipitate, and drying the precipitate under vacuum for 6 h to 20 h; and
(4) placing the precipitate obtained in the step (3) into a tubular furnace for calcination, introducing protective gas, heating to 300° C. to 1000° C. for 2 h to 8 h, and then naturally cooling to a room temperature to obtain the selenium-doped MXene composite nano-material.
2. The method of claim 1 , wherein the organic selenium source is at least one selected from the group consisting of phenylselenol, dimethyl selenide and dibenzyl diselenide.
3. The method of claim 1 , wherein the MXene is one or more selected from the group consisting of Ti 2 NT x , Mo 2 NT x , V 2 NT x , Ti 2 CT x , Mo 2 CT x and V 2 CT x .
4. The method of claim 1 , wherein the dispersant is at least one selected from the group consisting of N,N-dimethylformamide and ethanol.
5. The method of claim 1 , wherein the cleaning agent is at least one selected from the group consisting of water and ethanol.
6. The method of claim 1 , wherein a selenium doping amount in the selenium-doped MXene composite nano-material is 3 wt % to 8 wt %.
7. The method of claim 1 , wherein a stirring time in the step (1) is 1 h to 5 h.
8. The method of claim 1 , wherein the dispersion is heated to 110° C. to 200° C. after being transferred into the reaction kettle, and reacted for 12 h to 20 h in the step (2).
9. The method of claim 1 , wherein a rotation speed used for the centrifugation in the step (3) is 4000 rpm to 6000 rpm.
10. The method of claim 1 , wherein a temperature of drying under vacuum is 50° C. to 70° C., and a vacuum degree does not exceed 133 Pa.
11. The method of claim 1 , wherein the temperature is heated to 300° C. to 1000° C. with a heating speed of 3° C/min to 7° C/min in the step (4).
12. The method of claim 1 , wherein the protective gas is N 2 or Ar, and a gas flow speed is 180 ml/min to 300 ml/min.