Preparation method of ribbon-shaped graphite with high specific surface area

Abstract

The invention discloses a preparation method of ribbon-shaped graphite with high specific surface area. The preparation method comprises the following steps: preparing asphalt into tetrahydrofuran solution, which is designated as solution A; adding tetraethyl orthosilicate, deionized water and HF respectively into a stainless steel cup, and stirring magnetically at room temperature to obtain solution B; Add it into solution B, transfer it to a polytetrafluoroethylene reaction tank after stirring, and let it stand at 40-60°C until a gel is formed; dry the gel, and then pre-oxidize it in the air atmosphere for more than 3 h, Then in the carbonization furnace N 2 The temperature is raised to 600°C at low temperature, and then the temperature is raised to 600-1000°C, and the temperature is kept at a constant temperature for more than 10 minutes to obtain a composite product; the composite product is added to hydrofluoric acid for cleaning, then washed with distilled water until neutral, dried, and then put in graphite Raise the temperature to over 2000°C under argon in the melting furnace, and keep the temperature constant for 10 minutes to 1 hour to obtain ribbon-shaped graphite with high specific surface area. The raw materials used in the invention are cheap, the preparation cost is low, and the product has a high specific surface area.

Description

technical field [0001] The invention relates to the technical field of graphite preparation, in particular to a method for preparing ribbon-shaped graphite with a high specific surface area. Background technique [0002] Porous carbon materials are widely used as electrode materials for lithium-ion batteries, fuel cells and supercapacitors, and as adsorbents in separation processes and gas storage processes due to their high specific surface area, porosity, stability, and electrical conductivity. As well as the catalyst carrier in the important catalytic process, porous graphite is obtained after high-temperature graphitization of porous carbon materials. After high-temperature graphitization, porous graphite has excellent properties such as better stability and high electrical conductivity. However, after high-temperature treatment, the graphite microcrystals are arranged in an orderly manner to form graphite sheets, resulting in the disappearance of some pores and a decrea...

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Problems solved by technology

[0003] The porous expanded graphite prepared by the traditional high-temperature expansion method has a high specific surface area, but its porosity is very large, and the pore diameter is also large. The diameter of most pores is generally above the micron level, and the excessively large pores limit the performance of porous graphite. application, reducing the application effect; the use of activation drilling can obtain ultra-high specific surface area, but harsh activation will lead to the destruction of graphite crystallites; at the same time, the size of the pores is also an important factor affecting the application of graphite materials, such as in the field of energy storage When used as an electrode material, the micropores and mesopores in graphite act as energy storage sites and mass transfer channels, which will have a greater impact on the energy density and power density of the electrode.

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