Preparation method of self-support nitrogen-doped porous graphene for super-capacitor

Abstract

The invention discloses a preparation method of self-support nitrogen-doped porous graphene for a super-capacitor, which is characterized by comprising the following steps: 1) dispersing nano nickel powder into a buffer solution of dopamine / Tris-HCl, carrying out ultrasonic oscillation, and then carrying out mechanical stirring at room temperature for reacting and heating; after paste is formed, pressing the paste into a sheet by using a roller press of which the roller diameter is 50cm, so as to obtain a sheet-shaped nitrogen-doped porous graphene precursor; 2) by taking polydopamine in the sheet-shaped nitrogen-doped porous graphene precursor prepared in the step 1) as a solid precursor and taking nickel as a catalyst and a template, carrying out high temperature sintering in an inert gas sintering furnace, and finally, cooling the sintering product to room temperature in the inert gas, so as to obtain a nickel powder coated sheet of a nitrogen-doped graphene product; and 3) putting the nickel powder coated sheet of the nitrogen-doped graphene product, prepared in the step 2), into strong acid for etching off the nano nickel powder template by the acid, and then, cleaning and drying the sheet in ultra-pure water repeatedly, so as to obtain self-support nitrogen-doped porous graphene. The used raw materials are non-toxic and cheap and are easy to obtain, the process is simple, the cost is low, and nitrogen-doped graphene with a high specific surface area and high quality can be prepared.

Description

technical field [0001] The invention relates to the technology in the field of graphene, and in particular provides a method for preparing self-supporting nitrogen-doped porous graphene for supercapacitors. Background technique [0002] Supercapacitor, also known as Electrical Double-Layer Capacitor (Electrical Double-Layer Capacitor), is a new type of energy storage device, which has the characteristics of short charging time, long service life, good temperature characteristics, energy saving and environmental protection. Supercapacitors are used in a variety of applications. Used as a power balance power supply for lifting devices, it can provide super-large current power; used as a vehicle starting power supply, the starting efficiency and reliability are higher than traditional batteries, and can replace traditional batteries in whole or in part; used as traction energy for vehicles It can produce electric vehicles, replace traditional internal combustion engines, and t...

AI Technical Summary

Problems solved by technology

Two-dimensional graphene paper is an ideal integral and self-supporting supercapacitor electrode material due to its good conductivity and high specific surface area. However, in practical applications, the accumulation of graphene sheets makes the formation of double electric The effective area of ​​the layer is reduced

Most of the existing graphene nitrogen doping methods use high temperature or arc discharge in the gas phase system to dope nitrogen atoms into the graphene lattice, but these methods require professional equipment such as high vacuum systems, and high Dangerous hydrogen gas, corrosive ammonia gas, etc. have harsh preparation conditions, high cost, high risk, and the porosity of graphene cannot be guaranteed, so it is not suitable for large-scale production