Abstract: Disclosed is a method for preparing a carbon material, comprising applying a voltage to an electrically conductive medium to form an electrically conductive path in an oxygen-free environment containing a carbon source and a catalyst to obtain the carbon material, wherein the electrically conductive medium includes a solid substrate or a liquid-phase electrically conductive system; under the condition that the electrically conductive medium is the liquid-phase electrically conductive system, the carbon material is obtained in the liquid-phase electrically conductive system; and under the condition that the electrically conductive medium is the solid substrate, the carbon material is obtained on a surface of the solid substrate.

Abstract: The present invention relates to a printing device and a printing method. The combination mode between materials in an additive manufacturing process is improved. A calculation unit is used for controlling an A pole unit and a B pole unit to be in contact with, the materials, to form an energized circuit. The surface temperature of phase change material in the material between the A pole unit and the B pole unit is greater than or equal to a preset temperature so that the materials at a distance can be simultaneously combined.

Abstract: Disclosed is a method for preparing a carbon material, comprising applying a voltage to an electrically conductive medium to form an electrically conductive path in an oxygen-free environment containing a carbon source and a catalyst to obtain the carbon material, wherein the electrically conductive medium includes a solid substrate or a liquid-phase electrically conductive system; under the condition that the electrically conductive medium is the liquid-phase electrically conductive system, the carbon material is obtained in the liquid-phase electrically conductive system; and under the condition that the electrically conductive medium is the solid substrate, the carbon material is obtained on a surface of the solid substrate.