A method for preparing high-conductivity carbon materials by hydrothermal method

Abstract

The invention discloses a method for preparing a high-conductivity carbon material by virtue of a hydrothermal method. The method is characterized by comprising the following steps: by taking carboxymethyl cellulose as a raw material and taking pure water as a solvent, performing one-step high-temperature high-pressure hydrothermal treatment on a doping nitrogen source, and performing centrifugal separation, thereby obtaining a deep brown solid product; washing the brown solid product until the filtrate is clarified by using distilled water and absolute ethyl alcohol, performing vacuum drying, and performing high-temperature activation and pyrolysis on the obtained product, thereby obtaining a graphite-like structure carbon material with high nitrogen doping content and developed porous structure, wherein the carbon material has high conductivity and has potential application values in the field of preparation of lithium ion batteries and super-capacitors. The operation process has the main characteristics that the carboxymethyl cellulose is taken as the raw material and is environment-friendly, low in price and readily available, the nitrogen source is doped into carbon in the form of functional groups such as amino, pyridone and pyridine after the hydrothermal reaction and is subjected to high-temperature activation treatment so as to exist in a stable graphite nitrogen form, the graphite-like structure carbon material with high specific surface area and developed porous structure is generated, and high conductivity is promoted. The nitrogen source and the activation conditions are changed, so that carbon materials of different nitrogen doping amounts and pore structures can be controlled to be prepared, the conductivity is further adjusted, the highest conductivity of the prepared material can reach 120-166Sm<-1>, the method is simple and performance is excellent.

Description

Technical field: [0001] The invention relates to the field of preparation of nano-carbon materials, in particular to a method for preparing high-conductivity carbon materials by a hydrothermal method. Background technique: [0002] Since the discovery of graphene with excellent optical, electrical, and magnetic properties in 2004, carbon materials, especially carbon materials with special properties, have attracted widespread attention and research enthusiasm from scholars, and have been successfully used as adsorbents, catalysts, capacitors, etc. Carbon materials with excellent electrical properties represented by graphene are used in battery electrodes to effectively replace traditional heavy metal and metal oxide electrodes. However, at present, the preparation of carbon materials with excellent electrical conductivity is relatively simple, and the preparation conditions are high. Therefore, considering sustainable development, a new, simple and renewable method is develo...

AI Technical Summary

Problems solved by technology

It includes: mixing the sulfur element doped raw material or the sulfur and nitrogen two element doped raw material with carbon black, pouring it into water to make a uniformly dispersed suspension, drying the obtained material, grinding it, and calcining it in an inert atmosphere to obtain the product. It has certain electrochemical properties and is easy to operate. However, the nitrogen source and sulfur source for the reaction must be one or more of imidazole, thiophene, benzenesulfonamide, dithiocyanomethane, etc., and the time required for calcination and activation is relatively long , increasing the reaction cost and load

[0009] The Chinese patent with the publication number CN103212711A introduces a preparation method of highly conductive graphene oxide. After dopamine is deposited on the surface of graphene oxide after ultrasonic dispersion under alkaline conditions, the graphite oxide surface functionalized with polydopamine is Graphene is placed in the silver plating solution, and the reducing agent glucose solution is added for reduction. After the final heat treatment, the surface of the graphene oxide nanosheet with high shape coefficient is coated with a uniform and dense silver thin layer. The material has good coating performance, and the raw material is graphite. Higher cost restricts commercial application, and the ratio of glucose concentration to silver plating solution concentration has a great influence on the reduction effect

[0010] To sum up, at present, carbon materials with excellent electrical conductivity are mainly prepared by organic reagents to treat graphene oxide or carbon fiber, and after acid-base treatment, precious metals such as platinum or gold are loaded to obtain flake or layered materials; or imidazole, thiophene, etc. The reagents are N and S sources, and after high-temperature activation treatment, heteroatom-doped carbon materials with porous structure are obtained. These methods usually involve the reaction of organic reagents and noble metals, which have high requirements for reaction conditions, increase the environmental load and increase the reaction cost.

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