Preparation method of nitrogen/ sulphur co-doping three-dimensional graphene sponge

Abstract

The invention relates to a preparation method of a nitrogen / sulphur co-doping three-dimensional graphene sponge. The preparation method of the nitrogen / sulphur co-doping three-dimensional graphene sponge comprises the steps of firstly, fully dispersing a graphene oxide and thiourea mixture through an ultrasonic oscillating way, then filling the mixture into a hydrothermal reaction kettle, reducing the graphene oxide into graphene through high temperature and high pressure, meanwhile, self-assembling the graphene into a three-dimensional graphene macroscopic body, and doping a nitrogen element and a sulphur element into a graphene substrate; and finally, repetitively cleaning the three-dimensional graphene macroscopic body, and freeze drying to obtain the nitrogen / sulphur co-doping three-dimensional graphene sponge. The three-dimensional graphene sponge synthesized through hydrothermal reaction has the advantages of light weight and porosity, and is applied in a lithium-sulfur battery so as to be capable of improving the electrical conductivity of an anode material and solving the problem of big volume change during an electrode reaction process. The preparation method of the nitrogen / sulphur co-doping three-dimensional graphene sponge provided by the invention is simple and easy to implement, and is very applicable to engineering production.

Description

technical field [0001] The invention relates to a preparation method of a nitrogen / sulfur co-doped three-dimensional graphene sponge, which belongs to a preparation method of a graphene macroscopic body. Background technique [0002] Lithium-sulfur battery is a secondary battery that relies on the oxidation-reduction reaction of lithium and sulfur to cause the breaking / generation of sulfur-sulfur bonds and electron transfer to realize the mutual conversion between chemical energy and electrical energy. The theoretical specific energy of lithium-sulfur batteries is 2600Wh / Kg, which is currently the theoretical specific energy of lithium-ion batteries (500WhKg -1 ), it is recognized as the most promising lithium secondary battery for the next generation. It is expected to be widely used in portable electronic products, electric vehicles, aerospace vehicles, and power grid transmission. It plays a huge role in the development of today's society, economy, and technology, and ha...

AI Technical Summary

Problems solved by technology

However, the traditional two-dimensional graphene cathode material is difficult to increase its own specific surface area, and its contribution to the fixation of polysulfides is limited.